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The influence of an electric field on the growth of soy seedlings | In this paper we report the effect of electric fields on the growth of soy seedlings. Experiments performed in a dark, constant-climate chamber show that no significant change in the length of the seedlings was produced by an electrostatic field of 3600 V/m. On the other hand, a.c. electric fields of 3600 and 1800 V/m increase the average length of the seedlings by about 12% and 8%, respectively. The analysis, obtained by examining several thousands of seedlings, cultivated in well-controlled and reproducible conditions for a period of two years, is characterized by a very high statistical significance. Even if the underlying biophysical mechanism is still unclear, the result suggests the possibility to influence plant growth by using very low-frequency electric fields. | We explain the basic physics behind oscillatory effects in superconductor/metallic ferromagnet (S/F) sandwiches, and describe the important effects of the spin orbit scattering in these systems. We find that spin-orbit scattering plays a major role in the physics of the superconducting proximity effect with a conducting ferromagnet. As examples, we present calculations of the T{sub c} of an S/F bilayer and the Josephson current (near T{sub c}) of an S/F/S trilayer. {copyright} {ital 1997} {ital The American Physical Society} | eng_Latn | 28,000 |
Magnetic and structural properties of SmTiFe(11-x)Co(x) alloys | A high energy permanent magnet has to meet severe requirements in regard to high magnetization, sufficiently high Curie temperature, high anisotropy with a uniaxial easy magnetization direction, excellent physicochemical properties, low cost, etc. By virtue of a favorable combination of properties, SmCo5 and its structural derivative such as Sm2Co17 have been known as useful permanent magnetic materials for a number of years. Efforts to replace Co with the inexpensive Fe, which also has a higher magnetic moment, have been unsuccessful, since the R-Fe (R = rare earth) binaries do not form a compound isomorphous with SmCo5. | Abstract The discovery of a new isomer of the endohedral metallofullerene Sc 3 N@C 80 is reported. 13 C labeled (∼9%) Sc 3 N@C 80 has been synthesized and has been characterized by HPLC, mass spectroscopy and 13 C NMR data. The 13 C NMR spectrum shows six peaks with a 1:2:2:1:1:1 ratio that are assigned to the D 5h isomer. The results of theoretical calculations are also reported for the I h and D 5h isomers of Sc 3 N@C 80 . | eng_Latn | 28,001 |
Random anisotropy studies in amorphous Co–Er–B ribbons | Abstract We have studied the magnetization of melt-spun amorphous Co 80 − x Er x B 20 alloys with 0 ≤ x ≤ 7.5 under magnetic fields of up to 50 kOe, and have analyzed the results at 4.2 K on the basis of the random magnetic anisotropy model. The approach to saturation is established in the form of H −1/2 for various samples. The saturation magnetization, coherent anisotropy constant, local random anisotropy constant and the ferromagnetic correlation length were studied as a function of the Er composition. | We prove that any generic (i.e., possibly aperiodic) Lorenz gas in two dimensions, with finite horizon and non-degenerate geometrical features, is ergodic if it is recurrent. We also give examples of aperiodic recurrent gases. | eng_Latn | 28,002 |
COLLABORATION SUPPORTING MODEL OF SHARED OBJECTS FOR CSCW SYSTEMS | Information sharing is the basis of multi user collaboration in CSCW systems. First the requirements for the service of shared objects in CSCW is analysied. Then a collaboration supporting model of shared objects SOCSM/LSI is presented. The SOCSM/LSI uses the layered service interface to implement the cooperative functions such as access control, group awareness, and different presentation of shared objects. The SOCSM/LSI model can provide dynamic and flexible cooperative mechanisms for shared objects and can be applied to a quite wide range of CSCW applications. | This work benchmarks density functional theory, with several different exchange-correlation functionals, for prediction of isotropic one-bond phosphorus-hydrogen NMR spin-spin coupling constants (SSCCs). Our test set consists of experimental SSCCs from 30 diverse molecules representing multiple phosphorus bonding environments. The results suggest the importance of a balance between the choice of correlation functional and the admixture of nonlocal exchange. Overall, standard DFT methods appear to suffice for usefully accurate predictions of (31)P-(1)H SSCCs. | yue_Hant | 28,003 |
Metal complex of chlorophyll degradation product chlorin e6 derivatives as well as preparation method and applications of metal complex | The invention discloses a metal complex of chlorophyll degradation product chlorin e6 derivatives as well as a preparation method and applications of the metal complex. The metal complex of the chlorin e6 derivatives is shown in the formula I (shown in the specification), wherein R1 and R2 are H or CH3, CH2CH3, CH2CH2CH3, n-C4H9 and other common alkane groups, M is common divalent metal ions such as Cu , Zn , Fe , Mn , Ni , Co and Pd . The compound is clear in structure and excellent in activity, and has potential for developing anti-gastric ulcer and liver protection drugs. The metal complex is low in sources of raw materials, the preparation method is simple and fast to react, and suitable for large-scale industrial production. The formula is shown in the specification. | (Received 19 June 2011 ; in final form 25 February 2012) Abstract In this study, we investigated the spin dependent electronic transport of a fishbone-like nanostructure including two magnetic atoms at its ends. The electronic conductance of this nanostructure for three different orientations of atomic magnetic moments was numerically studied when the structure was sandwiched between two nonmagnetic leads. By using Green’s function technique at the tight-binding model, we calculated the spin dependent electronic transmission coefficient. The calculated results revealed that the conductance depends on the incident electron energy as well as the magnitude and orientation of atomic magnetic moments in the nanostructure. | eng_Latn | 28,004 |
Room-Temperature Ferromagnetism in Two-Dimensional Fe2Si Nanosheet with Enhanced Spin-Polarization Ratio | Searching experimental feasible two-dimensional (2D) ferromagnetic crystals with large spin-polarization ratio, high Curie temperature and large magnetic anisotropic energy is one key to develop next-generation spintronic nanodevices. Here, 2D Fe2Si nanosheet, one counterpart of Hapkeite mineral discovered in meteorite with novel magnetism is proposed on the basis of first-principles calculations. The 2D Fe2Si crystal has a slightly buckled triangular lattice with planar hexacoordinated Si and Fe atoms. The spin-polarized calculations with hybrid HSE06 function method indicate that 2D Fe2Si is a ferromagnetic half metal at its ground state with 100% spin-polarization ratio at Fermi energy level. The phonon spectrum calculation and ab initio molecular dynamic simulation shows that 2D Fe2Si crystal has a high thermodynamic stability and its 2D lattice can be retained at the temperature up to 1200 K. Monte Carlo simulations based on the Ising model predict a Curie temperature over 780 K in 2D Fe2Si crystal, ... | Abstract In this paper, fibrous membranes of poly(vinyl alcohol)/α-2-K 8 P 2 W 17 MO 61 (M = Co, Ni) were prepared by electrospinning technique. Calcining the fibrous membranes at 340 °C for 6 h, fibrous membranes of pure α-2-K 8 P 2 W 17 CoO 61 and α-2-K 8 P 2 W 17 NiO 61 were obtained, respectively. Fourier transformation infrared spectroscopy and X-ray diffraction showed that Dawson–Wells structure of the polyoxometalates was still remained in the fibrous membranes. Scanning electron microscopy images and diameter distribution curves of the fibrous membranes indicated that the average diameter of α-2-K 8 P 2 W 17 CoO 61 fibers was about 145 nm, and α-2-K 8 P 2 W 17 NiO 61 about 168 nm. The magnetic property of the fibrous membranes was investigated. | eng_Latn | 28,005 |
NG-monomethyl-l-arginine causes nitric oxide synthesis in isolated arterial rings: Trouble in paradise☆ | Abstract Arginine analogs are commonly used as inhibitors of the synthesis of endothelium-derived relaxing factor, nitric oxide. However, their effect on nitric oxide levels is rarely measured. Using a chemiluminescence assay for nitric oxide, we found that N G -monomethyl- l -arginine enhanced, rather than reduced, nitric oxide synthesis in pulmonary arterial and aortic rings. N G -monomethyl- l -arginine inhibited relaxation to the endothelium-dependent vasodilator A23187 in aortic but not pulmonary arterial rings. In contrast, N ω -nitro- l -arginine did not stimulate nitric oxide synthesis and it inhibited relaxation to A23187 in all rings. We conclude that N G -monomethyl- l -arginine is a partial agonist for nitric oxide synthesis. | We have performed high-throughput characterization of composition-spread La 1-x Ca x MnO 3 (LCMO) and Nd 1-x Sr x MnO 3 (NSMO) films, fabricated by the precursor technique, with a scanning SQUID microscope (SSM). In both films, SSM successfully observed spatial variation of magnetic field, corresponding to magnetic phase transitions with respect to chemical composition. The obtained magnetic phase diagrams basically reproduced those reported in bulk materials. However, several distinctive differences have also been noted. For instance, the region identified as a charge ordered insulator in LCMO revealed intense field, suggesting the occurrence of phase separation into ferromagnetic and non-magnetic states. These results confirm that SSM possesses sufficient analytical performance for high-throughput characterization of combinatorial magnetic libraries in composition spread form. | eng_Latn | 28,006 |
Fine Structure Zonal Flow Excitation by Beta-induced Alfven Eigenmode | Nonlinear excitation of low frequency zonal structure (LFZS) by beta-induced Alfven eigenmode (BAE) is investigated using nonlinear gyrokinetic theory. It is found that electrostatic zonal flow (ZF), rather than zonal current, is preferentially excited by finite amplitude BAE. In addition to the well-known meso-scale radial envelope structure, ZF is also found to exhibit fine radial structure due to the localization of BAE with respect to mode rational surfaces. Specifically, the zonal electric field has an even mode structure at the rational surface where radial envelope peaks. | ABSTRACTThis letter is motivated by an apparent paradox, in that some quaternary systems (particularly in the Ti–Zr–Al–C system) have been shown to exhibit M-site out-of-plane ordering, while prior work and calculations by the present authors suggest endothermic interactions between Zr and Ti. In this letter we provide a resolution to this issue and provide a more extended analysis on the out-of-plane and in-plane ordering in the M sites of quaternary MAX alloys. The results provide further insights to develop criteria to predict potential out-of-plane ordering tendencies in other MAX systems.fx1 | yue_Hant | 28,007 |
Magnetic susceptibility of the body-centred orthorhombic La2CuO4 system | A model Hamiltonian representing the Cu spins in La2CuO4 in its low-temperature body-centred orthorhombic phase, that includes both spin–orbit-generated Dzyaloshinskii–Moriya interactions and interplanar exchange, is examined within the RPA utilizing a Tyablikov decoupling of various high-order Green's functions. The magnetic susceptibility is evaluated as a function of temperature and the parameters quantifying these interactions, and compared to recently obtained experimental data of Lavrov, Ando, and collaborators. An effective Hamiltonian corresponding to a simple tetragonal structure is shown to reproduce both the magnon spectra and the susceptibility of the more complicated body-centred orthorhombic model. | The present invention relates to a laminate leadless carrier package comprising a semiconductor chip is installed on the edge of the concave section of the substrate for supporting the chip, wherein the substrate is coupled to the plurality of conductive layers and the dielectric layer, the optoelectronic chip, wire bond, and the substrate a has a wire bond pads located in the top surface. It covers at least a portion of the top surface of the substrate to encapsulate comprises a laser chip, wire bonding, and the recessed areas. This encapsulation is optically clear molding compound into. Packages are side-is arranged to be installed as rukeo-rukeo and / or top. | eng_Latn | 28,008 |
Crystal Shape Tailoring in Perovskite Structure Rare-Earth Ferrites REFeO3(RE = La, Pr, Sm, Dy, Er, and Y) and Shape-Dependent Magnetic Properties of YFeO3 | Controllable growth of perovskite oxide with tailored shapes is challenging but promising for shape-dependent physical and chemical property studies and probable applications. In this article, we report a general method for tailoring the crystal shape of perovskite structure rare-earth ferrite (REFeO3) crystals in hydrothermal conditions. By adjusting the ratio of KOH to urea, various shapes of REFeO3 crystals can be prepared, such as LaFeO3 truncated cubes, PrFeO3 perpendicular cross prisms, SmFeO3 crossed bars with trustum, DyFeO3 double pyramids on cubes, ErFeO3 distorted octahedrons, and YFeO3 long bars and thick hexagonal elongated plates. Detailed shape tailoring conditions for each phase of the crystals have been discussed clearly. The structure-dependent shape growing mechanism for each REFeO3 is generally discussed by consideration of the variance of reduced unit cell parameters in reference to the ideal cubic ABO3 perovskite structure. DyFeO3 was taken as an example to elucidate the crystal shap... | Abstract The behaviour of the stopped muons in the isostructural antiferromagnetic insulators α-Fe 2 O 3 and Cr 2 O 3 indicate a localized state below 500 K. Local fields and relaxation rates are measured and interpreted. | eng_Latn | 28,009 |
Interaction-Induced Spin Polarization in Quantum Dots | The electronic states of lateral many-electron quantum dots in high magnetic fields are analyzed in terms of energy and spin. In a regime with two Landau levels in the dot, several Coulomb-blockade peaks are measured. A zigzag pattern is found as it is known from the Fock-Darwin spectrum. However, only data from Landau level 0 show the typical spin-induced bimodality, whereas features from Landau level 1 cannot be explained with the Fock-Darwin picture. Instead, by including the interaction effects within spin-density-functional theory a good agreement between experiment and theory is obtained. The absence of bimodality on Landau level 1 is found to be due to strong spin polarization. | ABSTRACTThis paper aims to develop, assess, and numerically implement analytical models for the newly introduced Quintuple Friction Pendulum Isolator (QFPI) which can identically capture its real e... | eng_Latn | 28,010 |
Metal complex dye and display filter | Disclosed is a display filter (1) having a function of selectively absorbing light of a specific wavelength, wherein metal complex dyes (P, Q), which are characterized by being obtained by forming a complex of a methine dye, which is provided with a function as a neutral ligand, using tert-butyl salicylate boron complex, are arranged in a light path from a light-emitting source to the outermost surface of a viewing part. The selective light absorption wavelengths of the metal complex dyes (P, Q) are within the range from 480 nm to 510 nm. | Abstract The magnetic form factor of a single crystal Fe 0.66 Ni 0.34 Invar alloy was measured at room temperature and at liquid N 2 temperature by means of the polarized neutron diffraction technique. The self-consistent form factor analysis was made possible with the use of a spin only Fe spherical form factor. | eng_Latn | 28,011 |
Synthesis of Unsymmetrical Sulfides Derived from Tetrazole-5-thiols | A series of unsymmetrical sulfides derived from 1-substituted tetrazole-5-thiols was prepared by fusion of the corresponding 1-R-tetrazole-5-thiol sodium salt with 1-R'-5-halotetrazole. The structure was confirmed by 1H NMR and 13C NMR spectra. The target compounds were prepared in 50-80% yields. | The magnetically ordered phase of body-centered tetragonal UAu$_2$Si$_2$ was explored through $^{29}$Si-NMR experiments. The field-swept NMR spectra show asymmetric peak splitting below magnetic phase transition temperature, $T_{\rm m}$ = 20 K. This splitting is well explained by the occurrence of a magnetic order with propagation vector of $q$ = (2/3, 0, 0) and magnetic moments pointing parallel to the tetragonal [001] axis, offering evidence for uncompensated"up-up-down"-type antiferromagnetic ordering with a spontaneous [001] magnetization component. A symmetry analysis of the hyperfine-coupling tensor with phenomenological corrections including orbital and dipolar-field contributions yields the magnitude of the ordered moment to be approximately 1.4 $\pm$ 0.2 Bohr magneton per uranium ion, and evaluates the site-dependent hyperfine-coupling constants. | eng_Latn | 28,012 |
Physics in Jamaica: Some observations and recommendations | This paper presents an “inside view” of Physics in Jamaica – using several surveys over sixteen years as well as the experience from twenty five years of teaching Physics at the University of the West Indies, Mona Campus, Jamaica and, as the Physics Outreach Coordinator, the interaction with thousands of students, from Primary Schools as well as Grades 9 – 13 in High Schools. Many of the problems seen in Jamaican Physics are seen in other countries as well. Hence, the recommendations in the latter part of the paper are likely to be useful to many other countries too. | Abstract At an interface or junction, strong spin-orbit coupling with pairing inhomogeneity and small pair size on the heavy-electron side mean that coherent proximity or Josephson effects would occur for singlet to triplet as well as for singlet to singlet pairing states. | eng_Latn | 28,013 |
Magnetoelectric interactions in hot-pressed nickel zinc ferrite and lead zirconante titanate composites | The synthesis by hot pressing and wide-band (10Hz–1MHz) magnetoelectric (ME) characterization of bulk composites of nickel zinc ferrite Ni1−xZnxFe2O4 (NZFO) (x=0–0.5) and lead zirconate titanate (PZT) are reported. Hot-pressed samples show an order of magnitude improvement in ME voltage coefficient compared to sintered samples. Frequency dependence of ME coefficients show a three order of magnitude enhancement at electromechanical resonance. The ME coupling is maximum for samples with equal volume of ferrite and PZT. The strongest ME interactions are measured for samples of NZFO (x=0.2) and PZT. | The superposition-model suggested by Newman has been used to calculate the zero-field splitting parameters (ZFS) at room temperature that fit the experimental data taken from the literature. The satisfactory reproduction of experimental values of ZFS parameters indicates that Mn2+ substitute in place of Ni2+ and Mg2+ in the lattices and does not cause appreciable local distortion in the host crystals NSHH and MSHH. The calculations are made with the assumption that the total field experienced at an ion in a crystal is due to nearest neighbor ions, using power law exponent t2 = 7 ± 1 and t4 = 10 ± 1 the reference distance Rο = 0.22 nm for Mn2+ surrounded by oxygens. The superposition model analysis shows that for large values of ZFS parameters b 2 0 , b 2 2 , b 4 0 , b 4 2 and b 4 4 , intrinsic parameters \( \bar{b}_{ 2} \) and \( \bar{b}_{ 4} \) can be estimated with suitable errors but for small values of these spin–Hamiltonian parameters it is very difficult to predict the correct sign and magnitude. | eng_Latn | 28,014 |
Optical spin injection in CuGaSe2∕GaAs films | We have investigated polarization-resolved photoluminescence in epitaxially grown CuGaSe2∕GaAs(001) films. Spin-polarized excitons are optically excited both below and above the characteristic crystal field splitting of the chalcopyrite. At low temperatures, a large exciton spin polarization of 35% is measured under resonant pumping but this is reduced by an order of magnitude and reverses its sign for nonresonant excitation. The measurements suggest that optical pumping within a small energy window just above the band gap results in the preferential generation of light holes and electrons that exhibit a long spin relaxation time, comparable to the recombination time in CuGaSe2. | Progress in the understanding of negative resistance led to the concept of a Gunn oscillator, but realization of the device awaited development in GaAs technology. Device technology then increased rapidly. Most noticeable development lay in cavity operation, Frequency control, and LSA mode operation. Finally, the applications of the devices are reviewed. | eng_Latn | 28,015 |
Semiconductor surface protecting sheet and method | The present invention provides a material which is sufficient followability to the irregularities of the circuit surface of the semiconductor wafer, has a sufficient stiffness as grinding upon a support, the semiconductor surface protection with a material that is not fluidized by the repetitive temperature rise method and the surface protective sheet do. Surface protective sheet of the present invention is a surface protective sheet for protecting a circuit surface during the grinding process, the back surface of the semiconductor wafer, and a solid phase at room temperature, and the fluid at the time of heating, the surface protective layer to be cured at the time when heating or irradiation It has on the polymer film material. A semiconductor surface protective sheet, a semiconductor wafer, back grinding step | We explain the basic physics behind oscillatory effects in superconductor/metallic ferromagnet (S/F) sandwiches, and describe the important effects of the spin orbit scattering in these systems. We find that spin-orbit scattering plays a major role in the physics of the superconducting proximity effect with a conducting ferromagnet. As examples, we present calculations of the T{sub c} of an S/F bilayer and the Josephson current (near T{sub c}) of an S/F/S trilayer. {copyright} {ital 1997} {ital The American Physical Society} | eng_Latn | 28,016 |
Magnetic phase transitions of ζ-Mn5Ge2 in magnetic fields up to 25 T | Abstract Magnetization curves of ζ-Mn 5 Ge 2 single crystal are measured in pulsed magnetic fields up to 250 kOe for temperatures 77 ≤ T ≤ 480 K. The model ideas about the magnetic ordering of subphases ζ 1 and ζ 2 and the natures of the magnetic phase transitions which take place with T and H changing are discussed. | Abstract Amorphous Tb-Fe compositionally modulated films (CMFs) with alternating ultrathin Tb and Fe layers were sequentially deposited in a multitarget r.f. diode sputtering system. All of the Tb-Fe CMFs, except those with small Tb content, exhibited a large perpendicular anistropy. Compared with alloy films, the Tb-Fe CMFs exhibited anomalous structural and magnetic properties such as a compensation composition with increased Tb content, higher Curie temperatures, and an extension in the composition range of stable amorphous films to higher Tb contents. The atomic arrangements in this layered structure were modified by a variation of deposition parameters such as layer periodicity, substrate bias and composition. The primary factor responsible for the anomalies appeared to be the alignment of a strong atomic Tb-Tb and Fe-Fe pair distribution in the layers of the CMF. | eng_Latn | 28,017 |
Magnetic order in TM‐doped TiO2 single crystals | Needle shaped single crystals of TM-doped rutile TiO2 (TM = Cr, Mn, Fe, Co, Ni, Cu), grown in a sodium tetraborate melt with the flux method, are analysed in their structural and optical properties with a multi-technique approach. The ferromagnetic behaviour, observed up to room temperature, overlapping the prevailing expected paramagnetism, is investigated by means of static magnetization measurements performed at different temperatures and magnetic fields. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) | Protonic doping of polymer oligomers containing thiophene end groups or repeat units yields predominantly bipolaronic charge states. | eng_Latn | 28,018 |
Low-energy excitations of Yb As in a magnetic field | Abstract:We discuss the effects of an applied magnetic field on the low-energy excitations in the low temperature phase of Yb4As3. We show also why the magnetic interaction of the Yb3+ ions is nearly of an isotropic Heisenberg spin-1/2 type. A small anisotropy due to an intrachain dipolar interaction leads to the opening of a gap when a magnetic field is applied. The model agrees with available experimental data. Simple experiments are suggested in order to further test the present theory. | This Letter describes a calculation using superfield techniques, showing that the ..beta.. function is zero to three loops in N=4 supersymmetric Yang-Mills theory. This result gives further indication that the theory is likely to be finite and conformally invariant order by order in perturbation theory. | eng_Latn | 28,019 |
Mobile holes in a two-dimensional Heisenberg antiferromagnet. | Th {ital t}-{ital t}{prime}-{ital t}{prime}{prime}-{ital J} model is investigated by a rigorous diagonalization in a two-dimensional square lattice as large as {radical}20 {times} {radical}20 , which has no additional degeneracy. The ground state of one hole in the {ital t}-{ital J} model is at a momentum {bold k} near ({plus minus}{pi}/2,{plus minus}{pi}/2) with a total spin {ital S}=1/2 and that of two holes is at {bold k}=(0,0) with {ital S}=0. The hole pairing and nonclustering may be preferable for the ground state of the {ital t}-{ital t}{prime}-{ital t}{prime}{prime}-{ital J} model in the region of {ital t}{prime}{gt}0 and {ital t}{prime}{prime}{approx lt}0. | Abstract The accuracy of expanding the response of a molecule to an external electric field, E, as a power series in the field is investigated in the model hydrogen-bonded complex, ClH:NH3. Even at field strengths large enough to cause dramatic structural change in the complex, both the structure and vibrational frequencies are quantitatively predicted using only terms linear in E. These results suggest that knowledge of the zero-field molecular potential energy and dipole moment surfaces may be sufficient to accurately model the interactions of molecules in a wide range of external electric fields. | eng_Latn | 28,020 |
Thermal creep of beryllium pebble beds | Abstract Results from thermal creep experiments on beryllium pebble beds consisting of 1 mm NGK pebbles are presented. The experiments were performed in the uniaxial test facility HECOP II at temperatures ranging between 450 °C and 650 °C and under uniaxial stresses up to 3.6 MPa. A correlation of the type e cr = A exp − B T σ p t n was established. Compared to ceramic breeder materials, beryllium pebble beds are characterised by larger creep strains (by a factor 5–10) for given creep parameter values. For blanket conditions, these differences are smaller because characteristic temperatures are lower for beryllium than for the breeder material. For relatively short creep time periods, this factor is about 2–3. With these results, a complete set of data exists, required as input for codes used for the description of the thermal–mechanical interaction of solid breeder and beryllium pebble beds with the structural material of blanket elements. | We report on the observation of exchange bias and memory effect in double perovskite Sr$_2$FeCoO$_6$. Antiphase boundaries between the ferromagnetic and antiferromagnetic regions in the disordered glassy phase is assumed as responsible for the observed effect which reflects in the cooling field dependence and temperature evolution of exchange bias field and in training effect. The spin glass phase itself is characterized through memory, ageing and magnetic relaxation experiments. The spin glass transition temperature, $T_g$, versus $H_{dc}^{2/3}$ follows the Almeida-Thouless line yielding a freezing temperature, $T_f$ = 73 K. Time-dependent magnetic relaxation studies reveal the magnetization dynamics of the underlying glassy phase in this double perovskite. | eng_Latn | 28,021 |
Properties of Josephson junctions in the inhomogeneous magnetic field of a system of ferromagnetic particles | The effect of a system of ferromagnetic particles on the field-dependent critical current of a Josephson junction is experimentally studied for junctions of different geometries. For edge junctions, the effect of commensurability between the periodic magnetic field of the particles and the Josephson vortex lattice is observed. The effect manifests itself in additional maxima of the field-dependent critical current. For overlap junctions, giant (greater than sixfold) variations of the maximum critical current are observed depending on the magnetic state of the particles. The changes in the “Fraunhofer” pattern of the overlaped Josephson junctions are attributed to the formation of Abrikosov vortices due to the effect of uniformly magnetized particles. The effects revealed in the experiments can be used to analyze the inhomogeneous magnetic field of a system of submicron particles and to control the transport properties of Josephson junctions. | Abstract The Fubini-Halliday-Landshoff-type sum rules are applied in the pole-dominance approximation to current commutators taken between vacuum and vector as well as vacuum and axial-vector states. All the form factors appearing are given in terms of a single parameter. The results are consistent with those of ref. [1], and the number of free parameters there is further reduced. | eng_Latn | 28,022 |
Structural and Ferroelectric Properties of (1-X) Ba3.75Y0.83Nb10O30-XBa3.75Sm0.83Nb10O30 Solid | Solid solutions of (1-X) Ba3.75Y0.83Nb10O30-XBa3.75Sm0.83Nb10O30 were synthesized and examined with regard to their ferroelectric properties. No abnormal changes of lattice parameters were found over the investigated range of solid solution. Hysteresis curve measurement indicated that the polarization property could be improved by employing different rare earth cations. The coercive field (Ec) decreased as the composition approached Ba3.75Sm0.83Nb10O30. The remanent polarization (Pr) of the solid solution was higher than those of end members, and maximum values were observed at X=0.4-0.6. Variation of Curie temperature and cell distortion showed the same tendency as that of Ec. Atomic displacement calculated from refined structural parameters agreed with the abnormal change of Pr. The contribution of larger macroscopic polarization for X=0.4-0.6 region could be apparently attributed to the larger displacement of Nb5+ ions. | Low-temperature specific heat (SH) has been measured in KxFe2-ySe2 single crystals with T-c = 32 K. The SH anomaly associated with the superconducting transition is moderate and sharp, yielding a value of Delta C/T vertical bar T-c = 11.6 +/- 1.0 mJ/mol K-2. The residual SH coefficient gamma(0) in the superconducting state at T -> 0 is very small with a value of about 0.39 mJ/mol K-2. The magnetic-field-induced enhancement of the low-T SH exhibits a rough linear feature indicating a nodeless gap. This is further supported by the scaling based on the nodeless-gap approach of the low-T data at different magnetic fields. A rough estimate indicates that the normal-state SH coefficient gamma(n) is about 6 +/- 0.5 mJ/mol K-2, leading to Delta C/gamma T-n vertical bar T-c = 1.93 and placing this superconductor in the strong coupling region. | eng_Latn | 28,023 |
"Who formulated the ""Law"" that, in a paramagnetic material, the magnetization of the material is (approximately) directly proportional to an applied magnetic field, but if the material is heated, the magnetization is (approximately) inversely proportional to temperature?" | curie s law : definition of curie s law and synonyms of curie s law (English) Derivation with quantum statistical mechanics Magnetization of a paramagnet as a function of inverse temperature. A simple model of a paramagnet concentrates on the particles which compose it which do not interact with each other. Each particle has a magnetic moment given by . The energy of a magnetic moment in a magnetic field is given by Two-state (spin-1/2) particles To simplify the calculation , we are going to work with a 2-state particle: it may either align its magnetic moment with the magnetic field, or against it. So the only possible values of magnetic moment are then and . If so, then such a particle has only two possible energies and When one seeks the magnetization of a paramagnet, one is interested in the likelihood of a particle to align itself with the field. In other words, one seeks the expectation value of the magnetization : where the probability of a configuration is given by its Boltzmann factor , and the partition function provides the necessary normalization for probabilities (so that the sum of all of them is unity.) The partition function of one particle is: Therefore, in this simple case we have: This is magnetization of one particle, the total magnetization of the solid is given by The formula above is known as the Langevin paramagnetic equation . Pierre Curie found an approximation to this law which applies to the relatively high temperatures and low magnetic fields used in his experiments . Let's see what happens to the magnetization as we specialize it to large and small . As temperature increases and magnetic field decreases, the argument of hyperbolic tangent decreases. Another way to say this is this is sometimes called the Curie regime. We also know that if , then with a Curie constant given by . Also, in the opposite regime of low temperatures or high fields, tends to a maximum value of , corresponding to all the particles being completely aligned with the field. General case When the particles have an arbitrary spin (any number of spin states), the formula is a bit more complicated. For this more general formula and its derivation, see the article: Brillouin function . As the spin approaches infinity, the formula for the magnetization approaches the classical value derived in the following section. At low magnetic fields or high temperature, however, a simple Curie law is again obtained (where is the total angular momentum quantum number ): Derivation with classical statistical mechanics An alternative treatment applies when the paramagnetons are imagined to be classical, freely-rotating magnetic moments. In this case, their position will be determined by their angles in spherical coordinates , and the energy for one of them will be: where is the angle between the magnetic moment and the magnetic field (which we take to be pointing in the coordinate.) The corresponding partition function is We see there is no dependence on the angle, and also we can change variables to to obtain Now, the expected value of the component of the magnetization (the other two are seen to be null (due to integration over ), as they should) will be given by To simplify the calculation, we see this can be written as a differentiation of : (This approach can also be used for the model above, but the calculation was so simple this is not so helpful.) Carrying out the derivation we find where is the Langevin function : This function would appear to be singular for small , but it is not, since the two singular terms cancel each other. In fact, its behavior for small arguments is , so the Curie limit also applies, but with a Curie constant three times smaller in this case. Similarly, the function saturates at for large values of its argument, and the opposite limit is likewise recovered. Applications It is the basis of operation of magnetic thermometers , which are used to measure very low temperatures. See also | The Mothers of Invention, Frank Zappa - Burnt Weeny Sandwich - Amazon.com Music on February 13, 2006 Format: Audio CD Verified Purchase In some ways, the Mothers of Invention's BURNT WEENY SANDWICH picks up where HOT RATS, the fusion masterpiece their leader and guitarist Frank Zappa had released under his own name a few weeks earlier, left off. Both albums feature lengthy, largely improvised instrumental tracks, and both cross musical boundaries freely. But where HOT RATS was very much an exercise in jazz/rock, WEENY tends to showcase Zappa's modern classical influences a bit more, whether overtly (as in self-explanatory titles like "Igor's Boogie" and "Overture to a Holiday in Berlin") or more subtly (as in Ian Underwood's entrancing piano solo on "Aybe Sea"). Nevertheless, there's plenty for everyone in both of these albums, and while HOT RATS is ultimately the stronger of the two WEENY is likewise a top-of-the-line offering which never disappoints. Although the original Mothers had already disbanded by the time Zappa compiled and released WEENY in late 1969, the band's spirit is still evident in the sometimes jarring juxtaposition of styles, the insertion of brief "interlude" pieces between longer compositions and, inevitably, the humorous touches which adorn the album. Two doo-wop covers (a real rarity in Zappa's usually entirely self-composed musical universe), "WPLJ" and "Valarie," bookend WEENY beautifully, with Zappa proving as effective a pop vocalist as former Mother Ray Collins and bassist Roy Estrada providing a stunning falsetto on the latter tune. Read more › | eng_Latn | 28,024 |
Spins of odd-odd nuclei is difficult to predict. But $^{6}Li$ is light - only 6 nucleons. $^{6}Li$ should have spin $(\frac{3}{2} + \frac{3}{2}) = 3$ by shell model, as should have one proton on $p_{3/2}$ level and one neutron on $p_{3/2}$ level. How it is explained that it has spin 1? In the answers to question like that we see frequently formalism from some theory like $πp_{3/2}⊗νp_{3/2}$ and $3/2⊗3/2$. Please, explain to what theory that formalism belongs and explain how to understand it and where to read about. | Lithium-6 isotope has an approximate magnetic momentum of $0.88\ \mu_N$ in its fundamental nuclear state. I'm trying to find its angular momentum and parity. I found in a standard table: $I=1^+$ and while I get the parity part, I don't understand the rest. What I have done is filling the shells separately for protons and neutrons and finding that both have their outer particle in the $1 P_{3/2}$ state. Sum of these gives possible total angular momenta to be either $0$, $1$, $2$ or $3$. So my question is: how do you choose between these to find the real value $I=1$? | There should be infinitely many primes of the form $5+6n$. How do you prove it? The same should be true for $7+6n$. | eng_Latn | 28,025 |
Magnetic skyrmions for future potential memory and logic applications: Alternative information carriers | Current-induced skyrmion dynamics in constricted geometries | Real-space observation of a two-dimensional skyrmion crystal | eng_Latn | 28,026 |
THE INVERSION OF THE ANGLE OF HELICITY AS A CONFORMAL TRANSFORMATION IN MINKOWSKI'S SPACE-TIME | It is shown that inversion of the angle of helicity may be considered as a conformal transformation in Minkowski's space-time. The inversion of the angle of helicity takes place in the inversion of helicity of elementary particles. (C.E.S.) | Abstract In a previous paper we reported the measurements of both C/T and đ Q /d H of high-purity niobium as functions of the applied field at a number of chosen temperatures. In the present paper we analyze the slopes of these “magnetocaloric” quantities in the reversible region near H c2 . These slopes are related to the nonlinearity of the magnetization curve by means of a third-order field term in the Gibbs free energy. At the chosen temperatures the small values of the coefficient of this field term are calculated and found to be in agreement with the model of the reversible magnetization curve proposed by Kes. | yue_Hant | 28,027 |
SPIN-DEPENDENT CONDUCTANCE OF A TYPICAL FISHBONE-LIKE NANOSTRUCTURE | (Received 19 June 2011 ; in final form 25 February 2012) Abstract In this study, we investigated the spin dependent electronic transport of a fishbone-like nanostructure including two magnetic atoms at its ends. The electronic conductance of this nanostructure for three different orientations of atomic magnetic moments was numerically studied when the structure was sandwiched between two nonmagnetic leads. By using Green’s function technique at the tight-binding model, we calculated the spin dependent electronic transmission coefficient. The calculated results revealed that the conductance depends on the incident electron energy as well as the magnitude and orientation of atomic magnetic moments in the nanostructure. | In this paper, we extend our previous template analysis of a self-exciting Faraday disc dynamo with a linear series motor to the case of a nonlinear series motor. This introduces two additional nonlinear symmetry-breaking terms into the governing dynamo equations. We investigate the consequences for the identification of a possible template on which the unstable periodic orbits (UPOs) lie. By computing Gauss linking numbers between pairs of UPOs, we show that their values are not incompatible with those for a template for the Lorenz attractor for its classic parameter values. | yue_Hant | 28,028 |
MECHANISM OF CONDUCTION IN BaSn 1-x Sb x O 3-δ AND Ba 1-y La y SnO 3-δ | The temperature dependence of resistivity and magnetic susceptibility was measured for both BaSn 1-x Sb x O 3-δ and Ba 1-y La y SnO 3-δ systems below room temperature. The results show that the mechanism of conduction is the variable range hopping for both systems at lower temperature. Whereas the two types of mechanism of conduction at higher temperature, are considered the nearest-neighbor hopping (Ba 1-y La y SnO 3-δ )and as the excitation of electrons to the conduction band (BaSn 1-x Sb x O 3-δ ) | The $\Lambda\Lambda$-$\Xi N$-$\Sigma\Sigma$ coupling in $^{~6}_{\Lambda\Lambda}$He is studied with the [$\alpha$ + $\Lambda$ + $\Lambda$] + [$\alpha$ + $\Xi$ + $N$] + [$\alpha$ + $\Sigma$ + $\Sigma$] model, where the $\alpha$ particle is assumed as a frozen core. We use the Nijmegen soft-core potentials, NSC97e and NSC97f, for the valence baryon-baryon part, and the phenomenological potentials for the $\alpha-B$ parts ($B$=$N$, $\Lambda$, $\Xi$ and $\Sigma$). We find that the calculated $\Delta B_{\Lambda\Lambda}$ of $^{~6}_{\Lambda\Lambda}$He for NSC97e and NSC97f are, respectively, 0.6 and 0.4 MeV in the full coupled-channel calculation, the results of which are about half in comparison with the experimental data, $\Delta B^{exp}_{\Lambda\Lambda}=1.01\pm0.20^{+0.18}_{-0.11}$ MeV. Characteristics of the $S=-2$ sector in the NSC97 potentials are discussed in detail. | yue_Hant | 28,029 |
Magnetic Resonance Imaging of the Lumbothoracic Spine Under Compression | Central to the diagnosis of herniated intervertebral disc disease is magnetic resonance imaging (MRI). Yet every MR image of the spine is unphysiologic. The most comfortable position for a patient with a herniated disc is the supine one. It is the position in which Nachemson and Morris1 in 1964 found intradiscal pressure to be 15 to 25 kPa. Standing pressures were 100 kPa, while sitting pressures were 150 to 200 kPa. Equivalents in other units are 112.5 to 187.5 mmHg, 0.15 to 0.25 atm, and 1.69 to 2.22 psi supine. A sitting intradiscal pressure of 200 kPa 1500 mmHg 1.97 atm 29.6 psi. The highest intradiscal pressures naturally produce the most symtoms, and therefore it made sense to suggest that a sitting MRI would be the best MRI for diagnosing herniated disc disease. | Abstract A very promising spin physics programme will be soon on the way at the BNL Relativistic Heavy Ion Collider (RHIC). By studying the spin asymmetries for various processes (single photon, single jet and W ± production), we will compare the different predictions obtained using some sets of polarized parton distributions, available in the recent literature. We will put some emphasise on the analysis of the anticipated errors, given the event rates expected from this high luminosity new machine and the current acceptance for the detector systems at RHIC. | eng_Latn | 28,030 |
Why are only some materials ferromagnetic? I've been told in my solid state class, that ferromagnetism occurs when electron spins are alligned. This happens, as I understand it, when it is "energitically favorable" and when the wavefunction is antisymmetric (with a symmetric spin part). What I don't understand is: 1) When the spin part is symmetric and the electrons are alligned, the Coloumb repulsion is minimized (due to the Pauli principle, the electrons move further apart) - should it not always be more energitically favorable for the spins to be alligned? 2) Why, for instance, is iron (Fe) ferromagnetic, while Manganese (Mn) is paramagnetic? I fail to see where the theory comes into play. By looking at their orbital structure, Mn has more unpaired valence electrons than Fe. | Manganese has more unpaired electrons than Iron so why is Iron ferromagnetic Manganese paramagnetic? Manganese has five unpaired electrons, but Iron has four, then why is Iron ferromagnetic and Manganese paramagnetic? What's that property I'm missing? | What's the relationship between initial eigenvalues and sums of squared loadings in factor analysis? On the one hand I read in a comment that: You can't speak of "eigenvalues" after rotation, even orthogonal rotation. Perhaps you mean sum of squared loadings for a principal component, after rotation. When rotation is oblique, this sum of squares tells nothing about the amount of variance explained, because components aren't orthogonal anymore. So, you shouldn't report any percentage of variance explained. On the other hand, I sometimes read in books people saying things like: The eigenvalues associated with each factor represent the variance explained by that particular factor; SPSS also displays the eigenvalue in terms of the percentage of variance explained (so factor 1 explains 31.696% of total variance). The first few factors explain relatively large amounts of variance (especially factor 1), whereas subsequent factors explain only small amounts of variance. SPSS then extracts all factors with eigenvalues greater than 1, which leaves us with four factors. The eigenvalues associated with these factors are again displayed (and the percentage of variance explained) in the columns labelled Extraction Sums of Squared Loadings. That text is from Field (2013) Discovering statistics using IBM SPSS, and this diagram accompanies it. I'm wondering Who is correct about whether it's possible to speak of eigenvalues after rotation? Would it matter if it was an oblique or orthogonal rotation? Why are the "initial eigenvalues" different from the "extraction sums of squared loadings"? Which is a better measure of total variation explained by the factors (or principal components or whatever method is used)? Should I say that the first four factors explain 50.317% of variation, or 40.477%? | eng_Latn | 28,031 |
Why do bosons and fermions exist? if i have two particles in states: |1> and |2> respectavly , and they are not identical then the combined state is |1>|2> , but if they are identical then the labels 1 or 2 are arbitrary and could be swapped so supposedly we get two options: bosons = |1>|2> + |2>|1> fermions = |1>|2> - |2>|1> Why there are only these two options ? can't you have any arbitrary superposition of the two states ? (eg: a|1>|2> + b|2>|1> , a*a + b*b = 1) | Why must fermions be antisymmetric? I have read that fermions cannot exist in the same state simultaneously. I understand why indistinguishable particles with an antisymmetric superposition of states can't exist in the same state simultaneously, but why must fermions have an antisymmetric superposition of states? The only characterising property I know of fermions having besides antisymmetry is spin, for which they have half-integer. I understand that this is the case simply because particles with half-integer spin and particles with zero or integer spin were defined as fermions and bosons respectively. My perusal of the Wikipedia page on the leaves me under the impression that spin has nothing to do with the wavefunction's symmetry properties: Naively, neither has anything to do with the spin, which determines the rotation properties of the particles, not the exchange properties. Are antisymmetric wavefunctions simply classified as fermions, in the way half-integer spin particles were? I don't see how this could be the case, as, if spin and symmetry were independent, half-integer spin particles with symmetric wavefunctions (and antisymmetric integer spin particles) would be possible. | Fibonacci addition law $F_{n+m} = F_{n-1}F_m + F_n F_{m+1}$ Question: Let $F_n$ the sequence of Fibonacci numbers, given by $F_0 = 0, F_1 = 1$ and $F_n = F_{n-1} + F_{n-2}$ for $n \geq 2$. Show for $n, m \in \mathbb{N}$: $$F_{n+m} = F_{n-1}F_m + F_n F_{m+1}$$ My (very limited) attempt so far: after creating a small list of the values $F_0=0, F_1=1, F_2=1, F_3=2, F_4=3, F_5=5, F_6=8, F_7=13, F_8=21, F_9=34, F_{10}=55$ i can see that yes it does seem to work for instance $F_{6+3}=F_5 F_3 +F_6 F_4 = 10 +24 = 34 = F_9$. However, I really don't know where to begin as showing that this must hold in general terms. Should I be looking to use limits? Or perhaps induction? What is the best way to solve this? | eng_Latn | 28,032 |
Determine Polarity of Magnets | You might have heard the phrase, “opposites attract!” While perhaps not always the best advice for relationships, this cliché is the rule of thumb for magnet polarity. | Projection operators are defined below, given an arbitrary state | ψ ⟩ . {\displaystyle |\psi \rangle .}
| eng_Latn | 28,033 |
A slotted bowtie antenna with improved impedance matching is presented in this letter. Two elliptical patch resonators are loaded underneath each slot aperture of the traditional slot bowtie antenna fed by coplanar waveguide (CPW). The loaded elliptical patch enhances the electric coupling between the two edges of the triangular slot aperture and therefore decreases aperture impedance. The low aperture impedance results in a better impedance matching between the slot aperture and free space. High frequency simulation software ANSYS HFSS is used for accurate computation to determine the size and position of the patches. Prototypes of the parent and proposed antenna operating at center frequency of 2.1GHz are designed, fabricated and tested. The measured 10dB bandwidth of the proposed antenna is 64% from 1.45GHz to 2.8GHz. For comparison, return loss of the parent antenna is around 7dB in the same frequency band. | A compact double-layer Bowtie antenna optimized for medical diagnosis is presented in this paper. This on-body antenna is matched to the human body to allow more energy to be radiated into the human body to obtain stronger reflections for image processing. By using a Bowtie antenna with double layers as well as a folded structure and meandered microstrip lines at the bottom of the antenna, a small size of 30 × 30 mm2 with a size reduction of 40% is achieved, compared to the reference antenna of 50 × 50 mm2 within the same operational frequency range. After the optimization of the antenna parameters, the antenna is characterized from 0.5 to 2 GHz, where the low frequencies enable a high penetration into human body and the large frequency range contributes to a high bandwidth and hence a fine range resolution. The simulated and measured results are shown with respect to the impedance matching, near-field pattern, gain and SAR distributions. With features such as a very small size, very low operational frequency, high front-to-back ratio, this design shows a high potential for use in medical diagnosis of stroke, breast cancer and water accumulation detection in the human body. | Through the analysis of human skeletal remains and mortuary practice in Yinxu, this study investigates the impact of early urbanization on the commoners during the Late Shang dynasty (ca. 1250-1046 B.C.). A total of 347 individuals examined in this study represent non-elites who were recovered from two different burial contexts (formally buried in lineage cemeteries and randomly scattered in refuse pits). Frequencies of enamel hypoplasia (childhood stress), cribra orbitalia (childhood stress and frailty) and osteoperiostitis (adult stress) were examined to assess systemic stress exposure. Our results reveal that there was no significant difference in the frequency of enamel hypoplasia between two burial groups and between sexes, suggesting these urban commoners experienced similar stresses during childhood, but significantly elevated levels of cribra orbitalia and osteoperiostitis were observed in the refuse pit female cohort. Theoretically, urbanization would have resulted in increased population density in the urban centre, declining sanitary conditions, and increased risk of resource shortage. Biologically, children would be more vulnerable to such physiological disturbance; as a result, high percentages of enamel hypoplasia (80.9% overall) and cribra orbitalia (30.3% overall) are observed in Yin commoners. Adults continued to suffer from stress, resulting in high frequencies of osteoperiostitis (40.0% total adults); in particular, in the refuse pit females who may also reflect a compound impact of gender inequality. Our data show that the non-elite urban population in the capital city of Late Shang Dynasty had experienced extensive stress exposure due to early urbanization with further social stratification only worsening the situation, and eventually contributing to collapse of the Shang Dynasty. | eng_Latn | 28,034 |
Environmental concerns and responses in small-scale stone quarries in Nairobi | Impact of Stone Quarrying on the Environment and the Livelihood of Communities in Mandera County, Kenya | Recent advances in managing and understanding nephrolithiasis | eng_Latn | 28,035 |
The mines were the key to this growth but the mines are a rough trade. | The mines are necessary but difficult. | The mines are not important. | eng_Latn | 28,036 |
Siberian mineral sands mine delayed | According to Gurdin, implementation of the first stage of the project began in 2018, but securing the necessary funding to take forward the plans for the site has proved to be difficult. According to Tugansk Ore Mining & Processing’s website, the mine’s initial production target is 2.3 million tpy of ilmenite feedstock, ramping up to 6.9 million tpy over the years that follow. Neither Rostec nor Izurium Capital could be reached for comment at the time of publication, and some local media reports have cast doubt over Izurium’s participation in the project, given that there has been no evidence of the company conducting any financial activities in the past year and its website has been taken down. *Conversions made August 2019 CREDIT: | In the original publication the title of the article was published wrongly as “Geotechnical aspects and associated problems of Al-Shuaiba Lagoon soil, Red Sea c, Saudi Arabia”. | eng_Latn | 28,037 |
Diamonds, Gold and Coal, 1910–33 | At the time of Union in 1910, mining had already been firmly established as the leading sector of the economy. It generated 27 per cent of GDP, far in excess of the 17 per cent of agriculture, forestry and fishing, and the 7 per cent of manufacturing (figures are for the year ending in June 1912). Within the mining sector, gold was responsible for 75 per cent of the value of total production. This pre-eminence of gold continued during the first third of the twentieth century. It has been calculated that of the total value of minerals produced in South Africa up to the end of 1936, gold accounted for 75.6 per cent, diamonds for 16.3 per cent and coal for 5.4 per cent, with the remaining 2.7 per cent coming from copper, tin, silver, asbestos and other minerals.1 | This final report of the African Feed Resources Network - IDRC Project 3-p-90-0185 covers ::: the major activities and achievements during the first phase of the project, from lst April ::: 1991 to 31st March 1994. | eng_Latn | 28,038 |
National Underground Mines Inventory | Abstract : The purpose of this study was to identify and, to the extent that data are available, to characterize the underground, non-coal mines in the United States and to assemble the data obtained into a national inventory of underground mines having the potential of providing lodging and shelter as a civil defense measure during a natural or man-made disaster. Data were collected from the Mine Safety and Health Administration, the U.S. Bureau of Mines, from discussions with mine inspectors, and from mine owners and operators during visits to six underground mines. The data collected were incorporated into a computerized underground mine data file at the FEMA/Olney Computer Center. | Le fonds pan-europeen NEIF, conseille par BNP Paribas Real Estate Investment Services, obtient le label DGNB Silver pour l’immeuble Signaris a Francfort | eng_Latn | 28,039 |
Which element makes iron rust? | General Chemistry Online: FAQ: Redox reactions: How does iron rust? How does iron rust? When a droplet of water containing a little dissolved oxygen falls on an iron pipe, the iron under the droplet oxidizes: Fe(s) Fe2+(aq) + 2 e- The electrons are quickly snatched up by hydrogen ions and oxygen at the edge of the droplet to produce water: 4e- + 4 H+(aq) + O2(aq) 2 H2O(l) More acidic water is expected to increase corrosion so long as there is a sufficient supply of oxygen. If the pH is very low, and there isn't enough oxygen, the hydrogen ions will snatch up the electrons anyway, making hydrogen gas instead of water: 2 H+(aq) + 2 e- H2(g) But where's the rust? The equations above tell only a small part of the story. Hydrogen ions are being consumed by the process. As the iron corrodes, the pH in the droplet rises. Hydroxide ions (OH-) appear in water as the hydrogen ion concentration falls. They react with the iron(II) ions to produce insoluble iron(II) hydroxides: Fe2+(aq) + 2 OH-(aq) The iron(II) ions also react with hydrogen ions and oxygen to produce iron(III) ions. Fe2+(aq) + 4 H+(aq) + O2(aq) 4 Fe3+(aq) + 2 H2O(l) The iron(III) ions react with hydroxide ions to produce hydrated iron(III) oxides (also known as iron(III) hydroxides). Fe3+(aq) + 3 OH-(aq) Fe(OH)3(s) These can dry to make plain iron(III) oxide, Fe2O3. This is the red, powdery stuff we call "rust". Since these processes involve hydrogen ions or hydroxide ions, they will be affected by changes in pH. If you have other ions like calcium or carbonate present, they make a variety of precipitates that mix in with the iron hydroxide precipitates to produce a crusty, gnarled coating which can slow corrosion under some circumstances by cutting the iron off from the acid, water, and air supply. | Guns, Money and Cell Phones — Global Issues The Industry Standard Magazine Issue Date: Jun 11 2001 The demand for cell phones and computer chips is helping fuel a bloody civil war in the Democratic Republic of Congo. The offer turned up a few weeks ago on an Internet bulletin board called the Embassy Network. Among the postings about Dutch work visas and Italian pen pals lurked a surprisingly blunt proposal: "How much do you want to offer per kilogram? Please find me at least 100,000 U.S. dollars and I will deliver immediately." The substance for sale wasn't cocaine or top-grade opium. It was an ore called Columbite-tantalite - coltan for short - one of the world's most sought-after materials. Refine coltan and you get a highly heat-resistant metal powder called tantalum. It sells for $100 a pound, and it's becoming increasingly vital to modern life. For the high-tech industry, tantalum is magic dust, a key component in everything from mobile phones made by Nokia (NOK) and Ericsson and computer chips from Intel (INTC) to Sony (SNE) stereos and VCRs. Selling coltan is not illegal. Most of the worldwide tantalum supply - valued at as much as $6 billion a year - comes from legitimate mining operations in Australia, Canada and Brazil. But as demand for tantalum took off with the boom of high-tech products in recent years, a new, more sinister market began flourishing in the Democratic Republic of Congo. There, warring rebel groups - many funded and supplied by neighboring Rwanda and Uganda - are exploiting coltan mining to help finance a bloody civil war now in its third year. "There is a direct link between human rights abuses and the exploitation of resources in areas in the DRC occupied by Rwanda and Uganda," says Suliman Baldo, a senior researcher in the Africa division at Human Rights Watch, a New York-based nongovernmental organization that tracks human-rights abuses worldwide. The slaughter and misery in the Congo has not abated since the country's president, Laurent Kabila, was assassinated in January. (Kabila's son, Joseph, was quickly appointed the new head of state.) Human Rights Watch researchers, working with monitors in the Congo, estimate that at least 10,000 civilians have been killed and 200,000 people have been displaced in northeastern Congo since June 1999. Rebels have driven farmers off their coltan-rich land and attacked villages in a civil war raging, in part, over control of strategic mining areas. The Ugandan and Rwandan rebels "are just helping themselves," Baldo says. The mining by the rebels is also causing environmental destruction. In particular, endangered gorilla populations are being massacred or driven out of their natural habitat as the miners illegally plunder the ore-rich lands of the Congo's protected national parks. The link between the bloodshed and coltan is causing alarm among high-tech manufacturers. Slowly they are beginning to grapple with the possibility that their products may contain the tainted fruits of civil war. A similar controversy, after all, wracked the diamond industry in the late 1990s, when global demand for the gems helped finance civil wars in Sierra Leone, Angola and Liberia. Since then, the international community has clamped down on the diamond trade, imposing tougher import and export regulations. But with tantalum, such regulations may be difficult to enforce. The market for the metal is based on secretive and convoluted trade links subject to few international regulations, and the ore is not sold on regulated metals exchanges. Rape of the land The first wake-up call to the high-tech industry came in April when the United Nations issued a damning report on the "illegal exploitation of natural resources and other forms of wealth of the Democratic Republic of the Congo." After six months of field investigations, a panel of experts in the region assembled by the U.N. Security Council reported its findings. Among the most alarming of the report's allegations was that Rwandan, Ugandan and Burundian rebels had looted and smuggled thousands of tons of coltan from the | eng_Latn | 28,040 |
Determination of Heavy Metal Levels of Kondok Soills-Haftgel | Heavy metals in soil on spoil heap of an abandoned lead ore treatment plant, SE Congo-Brazzaville | Expression of Olig2, Nestin, NogoA and AQP4 have no impact on overall survival in IDH-wildtype glioblastoma | eng_Latn | 28,041 |
Environmental assessment and characterization of residues from coal processing and steel industry activities | Analysis of Cu and Zn concentrations in shellfish from Korean coasts | Surface of localized pleural plaques quantitated by computed tomography scanning: no relation with cumulative asbestos exposure and no effect on lung function | eng_Latn | 28,042 |
Bioremediation of waste water containing heavy metals Cadmium and Zinc using aquatic plant Pistia stratiotes L | Phytoaccumulation of Trace Elements by Wetland Plants: II. Water Hyacinth | Limits to the Biofortification of Leafy Brassicas with Zinc | eng_Latn | 28,043 |
Population health risk due to dietary intake of toxic heavy metals from Spinacia oleracea harvested from soils collected in and around Tshwane, South Africa ☆ | Assessment of Trace Metals Concentration in Tree Barks as Indicator of Atmospheric Pollution within Ibadan City, South-West, Nigeria | Exogenous growth factors do not affect the development of individually cultured murine embryos | eng_Latn | 28,044 |
Factors controlling the spatial variability of surface soil particles using GLMs and GAMs | Comparison of soil genetic classification and soil taxonomy for plain soil in Xinjiang | Surface of localized pleural plaques quantitated by computed tomography scanning: no relation with cumulative asbestos exposure and no effect on lung function | eng_Latn | 28,045 |
Screening of native plants and algae growing on fly-ash affected areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India for accumulation of toxic heavy metals. | Evaluation of Algae Farming Using the Chlorella Bioassay | Artificial incubation does not affect the post-hatch development, health, or survival of the Lance-tailed Manakin (Chiroxiphia lanceolata), a tropical passerine | eng_Latn | 28,046 |
Ecological risk assessment of trace metal accumulation in sediments of Veraval Harbor, Gujarat, Arabian Sea. | Molecular characterization and phylogenetics of Indian polychaete fauna: scope for implementation in ecological monitoring | Exogenous growth factors do not affect the development of individually cultured murine embryos | eng_Latn | 28,047 |
3D characteristic analysis-based targeting of concealed Kiruna-type Fe oxide-apatite mineralization within the Yangzhuang deposit of the Zhonggu orefield, southern Ningwu volcanic basin, middle-lower Yangtze River metallogenic Belt, China | Application of three-dimensional weights of evidence in modeling concealed ore deposits: Case study of a porphyry Cu deposit in the Urmia-Dokhtar magmatic belt of Iran | Porin channels in intact cells of Escherichia coli are not affected by Donnan potentials across the outer membrane. | eng_Latn | 28,048 |
Summary In this study, the effects of arsenic, cadmium, copper and chromium treatments were examined on a nematode community structure and proportion of functional groups in the microcosm for 30 days. The toxic effects on the nematode community did not correspond with metals mobility (EDTA extraction) in soil as it was expected. The most toxic element with a significant degradation of community structure was chromium (low mobile), which negatively affected almost all observed ecological parameters (abundance, diversity and ecological indices). On the other hand, cadmium and arsenic influence was negligible even in the plots treated with the highest concentrations and the communities resembled to the control samples. Copper showed a stimulative effect on the community under low concentration (40 mg.kg-1), while under higher concentrations the stimulation was replaced by stress responses. The widely used ecological indices, such as the Maturity Index 2-5, Structure Index, and Shannon-Weaver Index and c-p groups showed the best bioindication potential among nematode parameters. | The acute sensitivity to CuSO4 of a broad range of nematode taxa was analyzed in order to assess the potential of changes to nematode community structure to serve as a practical tool for the bioindication of heavy-metal pollution. An easy-to-use experimental set-up was developed along with an appropriate mathematical response model in order to quantify the response characteristics of nematodes to CuSO4 pressure. Three similar experiments were conducted using water, dune sand, and sandy soil as media, each of which was subjected to 12 increasing concentrations of CuSO4. In total, 130 response curves representing 70 nematode taxa were produced and analyzed. CuSO4 concentrations were normalized for differences in efficiency among media due to different adsorption. At low CuSO4 concentrations, many taxa exhibited stimulation rather than inhibition regarding recovery efficiency. At higher concentrations, the concentration level at which 50% of the nematode population was recovered after a 24-h incubation (recovery concentration 50% [RC50]) varied widely among taxa and ranged from 0.01 to 4 mM/L CuSO4 (normalized to water). Stimulation of recovery efficiency and RC50 were negatively correlated with the colonizer-persister (C-P) classification of taxa, which discriminates nematodes according to their reproductive potential. The maturity index, which relates to a nematode community's state of disturbance and eutrophication, was negatively correlated with CuSO4 concentration. The properties of the applied test method are discussed as are the relationships between the investigated short-term toxicity effects and long-term toxicity processes in the field. From the large range of observed RC50 values, it is concluded that a meaningful sensitivity classification of nematodes should be possible and thus would allow for a sensitive bioindication of heavy-metal pollution. From the correlation between RC50 and C-P classification, the authors further conclude that the maturity index will, in addition to enrichment and disturbance, respond to heavy-metal pollution and thus may serve as a general indicator of soil health. | Background:Rapid economic development in China has produced serious ecological, environmental, and health problems. Neurotoxicity has been recognized as a major public health problem. The Chinese g... | eng_Latn | 28,049 |
A method involving neutron activation followed by simple radiochemical separation was developed and applied to determine the concentrations of Th in blood serum and urine. The method is sufficiently sensitive to detect 0.025 ng of 232Th. The average concentration of Th found in the blood serum and urine of subjects from normal environments is 7.9 ng L-1 and 2.7 ng L-1, respectively. | This paper reports on the development, standardization, and application of instrumental as well as radiochemical neutron activation analysis (INAA and RNAA) techniques for determining the concentrations of iron, zinc, cobalt, cesium, strontium, selenium, thorium, and calcium in food consumed in India. Based on the analysis of 20 diet samples, prepared as per the data on dietary intake patterns of an adult in four provinces of India and that of an average adult Indian, the geometric mean (GM) intake of various elements for the reference Indian man was estimated to be 15.9 (10.7-34.4) mg for iron, 8.6 (5.1-15.6) mg for zinc, 17.0 (8.3-31.4) micrograms for cobalt, 4.76 (2.8-11.8) micrograms for cesium, 1.46 (0.79-2.96) mg for strontium, 52.4 (35.0-130.8) micrograms for selenium, 0.75 (0.44-1.75) micrograms for thorium, and 0.35 (0.17-0.67) mg for calcium. A comparison of the daily dietary intakes of these trace elements by the reference Indian man was made with that of the International Commission on Radiological Protection (ICRP) reference man and also with the world average compiled by the International Atomic Energy Agency (IAEA). When compared with the ICRP reference man data, the daily dietary intakes of all the eight elements by the reference Indian man were considerably lower by factors ranging from 1.4 for strontium to as much as 18.0 for cobalt. However, when compared with the world average, daily dietary intakes by the reference Indian man were comparable for iron and lower by factors 1.2 to 1.9 for zinc, selenium, and calcium. | This paper reports the concentrations of 137Cs, hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethanes (DDT) and its main degradation products, δ3C, and organic carbon in pond sediments (0–210 cm, sectioned by 2–20 cm interval) and surface soils (the 0–3 cm horizon) collected in 2010 from Chenjia catchment, which is located in Yanting county in the hilly central Sichuan of China. α-, β-, and γ-HCH, DDT, and DDD were not detected throughout the sediment profile. Trace concentrations of δ-HCH (0.89–29.31 ng g−1) and p,p′-DDE (1.85–6.02 ng g−1) were detected only in top 40 cm sediment. The 137Cs fallout peak in 1963 (corresponding to the 55–60 cm depth), the sedimentary signature left by the last year of HCH use in 1989 (an additional indicator at 20–25 cm), and the obvious original channel bed prior to the construction of the pond in 1956 were used as temporal markers to estimate changes in average sedimentation rate between different periods due to changes in land use. Continuous, marked decrease in average sedimentation rate (i.e., 3.79, 1.35 and 1.07 cm year−1 in 1956–1963, 1963–1989, and 1989–2010, respectively) over time was observed, probably due to the reforestation, abandoning of steep sloping farmland for afforestation and natural re-vegetation (implementation of the Grain for Green Program), and the conversion of part of gently sloping farmland terraces to orchard land since the 1980s, especially since the 1990s. This was corroborated by the observed decrease (more negative) in δ13C of sediment towards the surface, which indicates increased relative contribution of eroded soil particles coming from slopes with increased tree cover in sediment source area. Combined use of 137Cs, δ-HCH, and δ13C record in sediments has been demonstrated to be a powerful approach to reconstruction of response in sedimentation rate to historical land use changes. | eng_Latn | 28,050 |
Study has be carried out for recovering the gold in cyanide residue by column flotation system,which included one-stage of roughing,one-stage of cleaning and one-stage of scavenge column in a closed-circuit separately,as a result,the concentrate grade of Au is 31.75 g/t,and the recovery of Au is 27.93% under the condition with crude grade of 0.91 g/t.Aiming to the changing feeding ore property at later stage,the column flotation equipment performance has been tested and the influence of different parameters such as ultrasound approach to the flotation process is compared as well. | Two flotation columns replacing traditional flotation machine and vertical agitate mill were successfully used on copper production in Yangla mine. With introducing of these advanced machines, chalcopyrite with fine dissemination size could be absolutely liberated. In addition, the technological process was further optimized. And Cu grade was improved by 3%, the recovery of Cu, Au and Ag were improved by 3% respectively. | By using a superluminescent diode as the light source and a depolariser inside the fibre coil, a constant scale factor is achieved without using polarisation control elements. For long-term behaviour an RMS-bias drift of 10 degrees/h is obtained. | eng_Latn | 28,051 |
This work presents a methodology to assess the environmental potential risk of soils when submitted to different conditions. The potentially toxic element (PTE) behaviour was evaluated by single chemical extractions in order to simulate four conditions: PTEs leaching under actual rainfall conditions; acid mine drainage; and an anoxic and an oxic environment. Soil pollution assessment was carried out using the contamination factor (CF) and the pollution load index (PLI) for total contents and indicators of mobility were established for each extraction: natural mobility indicator (NMI), acid mine drainage mobility indicator (AMI), oxic mobility indicator (OMI) and anoxic mobility indicator (ANMI). The total PTE content in the samples was high, and this content decreased when the distance of the sampling site to the source of contamination increased. The results obtained after the extractions suggested that the highest PTE content was extracted in the acidic medium. The mineralogical composition is an important factor that should be taken into account in the evaluation of PTE mobility, firstly because the mineral phases react differently in the proposed situations depending on their chemical nature, and secondly, because the presence of a particular phase (with different degree of reactivity) depends on the degree of weathering. The most reactive materials under oxic conditions are, in the study area, the most modern. The proposed indices may constitute a first attempt to define areas with high potential environmental risk, where urgent action is needed. In addition, the proposed methodology could be a valuable tool to prioritise these interventions. | Exposed mine tailing wastes with considerable heavy metals can release hazardous colloidal particles into soil under transient chemical and physical conditions. Two-layered packed columns with tailings above and soils below were established to investigate mobilization and transport of colloidal particles from metal-rich mine tailings into soil under transient infiltration ionic strength (IS: 100, 20, 2 mM) and flow rate (FR: 20.7, 41, and 62.3 mm h(-1)), with Cu and Pb as representatives of the heavy metals. Results show that the tailing particles within the colloidal size (below 2 μm) were released from the columns. A step-decrease in infiltration IS and FR enhanced, whereas a step-increase in the IS and FR restrained the release of tailing particles from the column. The effects of step-changing FR were unexpected due to the small size of the released tailing particles (220-342 nm, being not sensitive to hydrodynamic shear force), the diffusion-controlled particle release process and the relatively compact pore structure. The tailing particles present in the solution with tested IS were found negatively charged and more stable than soil particles, which provides favorable conditions for tailing particles to be transported over a long distance in the soil. The mobilization and transport of Cu and Pb from the tailings into soil were mediated by the tailing particles. Therefore, the inherent toxic tailing particles could be considerably introduced into soil under certain conditions (IS reduction or FR decrease), which may result in serious environmental pollution. | The principal impediment to gene therapy is the development of efficient, nontoxic gene carriers that can handle and deliver foreign genetic materials into various cell types, including healthy and... | eng_Latn | 28,052 |
Three lacustrian sediment samples were collected from Chaohu Lake in December 2002 in the Yangtze delta region. These samples were analyzed using a Laser Analyzer and obtained grain-size parameters. Sedimentation rates were determined with radioisotopes ~(137)Cs and the average sedimentary rates are 0.29cm/a,0.35cm/a and 0.24cm/a in Cores C1, C2 and C3, respectively. The grain-size parameters of the deposits vary regularly with the fluctuation of hydrodynamics. There are many differences of sedimentation rates in different periods. These varies have important relations between sedimentary environment and human activities. | In the present study, surface sediment samples from 48 sites covering the whole water area and three main estuaries of Chaohu Lake were collected to determine the concentrations of 25 metal elements using microwave-assisted digestion combined with ICP-MS. Spatial variation, source appointments, and contamination evaluation were examined using multivariate statistical techniques and pollution indices. The results show that for the elements Cd, Pb, Zr, Hf, U, Sr, Zn, Th, Rb, Sn, Cs, Tl, Bi, and Ba, which had higher coefficients of variation (CV), the concentrations were significantly higher in the eastern lake than in the western lake, but other elements with low CV values did not show spatial differences. The accumulation of Cu, Zn, Rb, Sr, Zr, Cd, Sn, Cs, Ba, Hf, Ta, Tl, Pb, Bi, U, and Th in the surface sediments was inferred as long-term agricultural cultivation impact, but that of Ti, V, Cr, Mn, Co, and Ni may have been a natural occurrence. The contribution from industrial and municipal impact was negligible, despite the rapid urbanization around the studied area. Principal component analysis-multiple linear regression (PCA-MLR) predicted the contribution from agricultural activities to range from 0.45 ± 1.31 % for Co to 92.7 ± 17.7 % for Cd. The results of the pollution indices indicate that Chaohu Lake was weakly to moderately affected by Ti, V, Cr, Mn, Co, and Ni but was severely contaminated by Hf and Cd. The overall pollution level in the eastern lake was higher than that in the western lake with respect to the pollution level index (PLI). Therefore, our results can help comprehensively understand the sediment contamination by metals in Chaohu Lake. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,053 |
The level and tissue bioconcentration of V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd and Pb were determined ::: in the viscera and shell of the freshwater snail, Melanoides tuberculata in the upstream and downstream of Alaro ::: stream, South West Nigeria. Trace metal concentrations in snail and sediment samples collected from six stations ::: were measured using an Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). ::: The mean trace metal concentrations (ppm) of V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd and Pb in the ::: snail were estimated to be 2.10-3.26, 28.31-33.32, 1668.21-2398.43, 1.75-3.98, 6.18-8.12, 33.86-89.23, 12.10- ::: 66.35, 0.78-0.96, 9.86-11.35, 1.44-1.73, 1.98-2.33, 2.88-3.22 and 10.12-14.12 respectively. The study shows that ::: M. tuberculata is capable of bioconcentrating trace metals in magnified quantity than that found in the sediment. The ::: tissue concentration pattern was correlated with the amount of trace metals in the sediments. Bioconcentration of ::: the trace metals V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd and Pb varied between the viscera and the shell with ::: the viscera having the highest concentration of all the trace metals. Results of the study indicate that ingestion of ::: sediments and algae may be the main uptake route of the trace metals in Melanoides tuberculata. | Accumulation of Zn, Cu, Pb and Cd was studied in snails fed for 120 days on diets contaminated with each metal separately and with all metals mixed together. The concentrations of Zn in food were in the range 39 to 12 200 mg kg −1 , Cu 9–1640 mg kg −1 , Pb 0.4–12 700 mg kg −1 , and Cd 0.16–146 mg kg −1 on a dry weight basis. At the highest concentrations of all metals the consumption rates decreased significantly. For the remaining concentrations, Zn and Cu were accumulated in soft tissue in proportion to their concentrations in food. The lowest treatments of Pb and Cd did not cause any increase in soft tissue concentrations of these metals but at average treatments, a clear increase was observed. Copper was accumulated especially efficiently, exceeding concentrations in food throughout the whole range of treatments. Except for the lower end of experimental treatments, Zn was accumulated approximately in direct proportion to its concentration in the diet. Lead was the most efficiently regulated metal, with soft tissue concentrations always substantially lower than in food. Approximately 60% of Zn, 90% of Cu, 43% of Pb and 68% of Cd on average was assimilated from food. The assimilation efficiency of food alone was ca 74%. The concentrations of metals in shells increased significantly with exposure, but (with one exception) the concentrations in shells did not exceed 5% of those found in soft tissue. We argue that snails are more important as agents of food-chain transport of Cu and Cd, than of Zn or Pb. Our results indicate also that snails are not able to deposit significant quantities of metals in their shells, at least during the time scale of our laboratory experiment. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,054 |
The ever increasing amount of solid waste generated which is exacerbated by lack of proper waste management system is of growing environmental and public health concern worldwide and in major towns and cities of Ethiopia. The aim of this study was to assess the current solid waste generation rate and compositions in Wolaita Sodo town, Southern Ethiopia. A cross-sectional survey and quantitative methods was used, and a multi-stage sampling method was employed including stratified random sampling, systematic random sampling, and purposive sampling. For house hold survey, sample size was determined using a population proportion formula. Structured and semi-structured questionnaire were used for interview, and direct waste analysis at source was used for waste characterization. A total of 378 household heads and 30 key informants were interviewed. The study showed that solid waste generation rate of Sodo town is 0.47 Kg/cap/day and this is greater than most major towns of Ethiopia. The major sources of municipal solid waste were residential, commercial and institutional sectors. The composition by weight of the households were food (59.5%); ash and dust (25.08%); yard waste (11.6% ); plastics and rubber (2.04%); paper and cardboard (1.12%); and textile, wood, glass and metals accounted only 0.1%, 0.16%, 0.2% and 0.2% wastes, respectively. More than 97.6% of solid wastes generated from households and 93.7% of municipal solid waste were biodegradable wastes. The study revealed that the town generates about 18,858,464 Kg of solid waste by wet weight per year. The town municipality must develop an appropriate solid waste management plan and implement to properly manage this huge amount of solid waste. Keywords: Wolaita Sodo, Solid waste, generation, composition | I Perspectives 1 Evolution of Solid Waste Management 2 Legislative Trends and Impacts II Sources, Composition, and Properties of Solid Waste 3 Sources, Types, and Composition of Municipal Solid Waste 4 Physical, Chemical, and Biological Properties of Municipal Solid Waste 5 Sources, Types and Properties of Hazardous Wastes Found In Municipal Solid Waste III Engineering Principles 6 Generation of Solid Wastes 7 Waste Handling and Separation, Storage, and Processing at the Source 8 Collection of Solid Wastes 9 Separation and Processing and Transformation of Waste Materials 10 Transfer and Transport 11 Disposal and Solid Wastes and Residual Matter IV Separation, Transformation, and Recycling of Waste Materials 12 Materials Separation and Processing Technologies 13 Thermal Conversion Technologies 14 Biological and Chemical Conversion Technologies 15 Recycling of Materials Found in Municipal Solid Waste V Closure, Restoration, and Rehabilitation of Landfills 16 Remedial Actions for Abandoned Waste Disposal Sites VI Solid Waste Management and Planning Issues 17 Meeting Federal and State Mandated Diversion Goals 18 Implementation of Solid Waste Management Options 19 Planning, Siting, and Permitting of Waste Management Facilities Appendixes | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,055 |
CHARACTERISTIC OF PRIMARY HALO AND PREDICTION OF HIDDEN OREBODY OF SHIYINGTAN GOLD DEPOSIT IN XINJIANG | Discussion on Geological and Geochemical Methods for Prospecting at Surrounding of Crisis Mines | Oral insulin does not alter gut microbiota composition of NOD mice | yue_Hant | 28,056 |
Fractionation and mobility of cadmium and zinc in urban vegetable gardens of Kano, Northern Nigeria | Transport of heavy metals in surface runoff from vegetable and citrus fields | Unusual low plasma levels of zinc in non-pregnant Congolese women | eng_Latn | 28,057 |
Trace metal concentrations in hairs of three bat species from an urbanized area in Germany. | The exposure level of heavy metals at four different locations near Gan-Ning-Meng reaches of the Yellow River, China | Transition metal-free one-pot synthesis of nitrogen-containing heterocycles | eng_Latn | 28,058 |
Human health risk assessment due to metals in cow’s milk from Singhbhum copper and iron mining areas, India | Assessing the health risk of heavy metals in vegetables to the general population in Beijing, China | No iron fertilization in the equatorial Pacific Ocean during the last ice age | eng_Latn | 28,059 |
The spatial distribution and its pollution characteristics of Hg, Cd, Cu, Zn, As, Pb and Ni for different layers at 0 ~ 20 cm, 20 ~ 40 cm, 40 ~ 60 cm soil depths were studied using methods of traditional statistics,geo-statistics and geo-accumulation index evaluation in Miyun Reservoir catchment. Results showed that soil heavy metals' coefficient of variation in topsoil and subsoil of this area were at middle level which reflected that they all had self-correlative structure, but did not destroy the original spatial structure although they have affected by human factors. The Kriging method is applied to calculate the unobserved points and is used to generate the contour map. The results illustrated that the spatial distribution of soil Hg, Cd, Cu, Zn, As, Pb(except soil Ni) had the same spatial distribution character which was higher in the north and lower in the southeast of this area. Soil Hg, Cd and As contents were relatively higher in Bai Rivers and its branches drainage area in different soil layers which indicated that this was related with mine exploitation in the upriver of the area since 1980s, but was not related with the different land utilization mode such as orchard, vegetable and crops planting. The Geo-accumulation Index suggested that heavy metals like Pb, As, Hg, Cd, Cu and Zn did not caused contamination in the first protective area of Miyun Reservoir,but soil metal Cd was very serious to the middle and high pollution degree, the government should take an importance attention to this. The results can provide scientific basis for effective monitoring and management of heavy metal pollution in the protective area of Miyun Reservoir. | The paper divided the whole coal life cycle, explained each phase characteristics, and took coal mine in China as a study case to assess the ecological risk in coal utilization phase. The main conclusions are as follows: (1) the whole coal life cycle is divided into coal mining, processing, transportation, utilization, and waste disposal. (2) The key points of production organization and characteristics in the five phases have great differences. The coal mining phase is characterized by the damage of the key ecological factors (water, soil, atmosphere, vegetation, etc.) damaged while the coal processing phase by discharging waste. The characteristics in coal transportation phase mainly performance as escaping and migration of atmospheric pollutants. In coal utilization phase, the main characteristics are aggravation of greenhouse effect. The main characteristics of waste disposal phase are accumulation of negative ecological effects on the land. (3) The ecological risk of soil heavy metals is serious in coal utilization phase. The potential ecological hazard coefficients of Pb and As in coal, residue and ash are all lower than 40, presenting low environmental impact on soil; the potential ecological risk coefficients of Cd are higher than 60, nearly half of their potential ecological risk coefficients are higher than 160, which presents high environmental pollution impact on soil; Hg’s potential ecological risk coefficients are higher than 320, presenting the highest environmental pollution impact on soil; the comprehensive pollution indexes in coal, residue, and ash are relatively high, which means the pollution hazard potential to soil environment is high. (4) The ecological risk of the atmospheric solid suspended matter is relatively strong in coal utilization phase. The ecological risk of Cd and As in primary flue gas is both lower than net flue gas. The geoaccumulation indexes of Cd and Hg in primary flue gas and net flue gas are both higher than 5, presenting the very strong ecological risk; 50 % of the geoaccumulation index values of As are between 3 and 4, which has also presenting a strong ecological risk while Pb does not present the ecological risk characterization. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,060 |
Paspalum notatum Flugge has been widely utilized for the purpose of ecological restoration of degraded land in the tropics and subtropics, where soil active aluminium (Al) is usually high as a result of acidification. Pot experiments were conducted to determine Al toxicity on P. notatum and to compare its potential to remove Al with another three plant species, Vetiveria zizanioides, Tristania conferta and Schima wallichii. In the Al addition experiment, the biomass of P. notatum and Al accumulation significantly decreased as the added Al concentration increased, but Al concentration in the plant markedly increased. A parallel experiment was conducted with the above four species, grown in lateritic soil and in oil shale waste containing high concentration of active Al. The biomasses of all four species were reduced obviously in the waste compared to in the soil. The effects of substrate on Al concentration, accumulation and translocation efficiency differed among species, and plants had significantly high... | Plants colonizing metalliferous soils have evolved physiological mechanisms which enable them to tolerate metal toxicity. These mechanisms do not generally suppress metal uptake but result in internal detoxification. Two basic strategies of plant response are suggested, accumulators and excluders. In the former, metals can be concentrated in plant parts from low or high background levels. By contrast, differential uptake and transport between root and shoot in excluders, lead to more or less constant low shoot levels over a wide range of external concentration. ‘Indicators’ are seen as a further mode of response where proportional relationships exist between metal levels in the soil, uptake and accumulation in plant parts. The physiological properties of accumulator and excluder species are considered in relation to metal tolerance mechanisms. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,061 |
This study investigated the factors influencing the simultaneous removal of Cd2+, NO3-N and hardness from water by the bacterial strain CN86. Optimum conditions were determined experimentally by varying the type of organic matter used, initial Cd2+ concentration, and pH. Under the optimum conditions, the maximum removal ratios of Cd2+, NO3-N and hardness were 100.00, 89.85 and 71.63%, respectively. The mechanism of Cd2+ removal is a combination of co-precipitation with calcium carbonate and pH. Further confirmation that Cd2+ can be removed by strain CN86 was provided by XRD and XPS analyses. Meteorological chromatography analysis showed that N2 was produced as an end product. These results demonstrate that the bacterial strain CN86 is a suitable candidate for simultaneously removing Cd2+, NO3-N, and hardness during in wastewater treatment. | Soils samples collected during different geochemical surveys of the city of Kajaran located near the biggest Cu-Mo mining area in Armenia were subjected to the multivariate geostatistical analysis and geochemical mapping in order to reveal soil heavy metals spatial distribution pattern and assess human health risk level under continuous impact of mining activities. In addition, human health risk assessment was done for the contents of Pb, Cu, Zn, Co, Mo, Mn, Ti, and Fe. The results of Principal Component Analysis and Cluster Analysis verify each other and were also complemented by the spatial distribution features of studied heavy metals indicating that two groups of elements have been generated. The first anthropogenically predominated group includes the main industrial elements Mo and Cu, and their accessories Pb and Zn while Ti, Mn, Fe and Co with the naturally predominant contents were observed in the second group. Moreover, the study reveals that the superposition of geogenic and anthropogenic components lead to the alteration of the shapes of areas with the high natural contents of heavy metals and formation of polluted areas with the intensive anomalies of elements. Health risk assessment showed that Mo was the only studied element which poses a non-carcinogenic risk to adult and children's health in some sampling sites during the whole period of investigations. Moreover, in all studied locations multi-elemental non-carcinogenic risk to children health from all studied heavy metals were detected. Special attention was given to the soils of kindergarten territories, and the results indicated that Hazard Index in kindergartens was >1 indicating an adverse health effect to children. The results obtained can serve as a basis for the development and implementation of risks reduction measures and systematic monitoring program planning. | ABSTRACTUNC-45A is an ubiquitously expressed protein highly conserved throughout evolution. Most of what we currently know about UNC-45A pertains to its role as a regulator of the actomyosin system... | eng_Latn | 28,062 |
This study aims to assess the spatial patterns of selected dust-borne trace elements alongside the river Indus Pakistan, their relation with anthropogenic and natural sources, and the potential risk posed to human health. The studied elements were found in descending concentrations: Mn, Zn, Pb, Cu, Ni, Cr, Co, and Cd. The Index of Geo-accumulation indicated that pollution of trace metals were higher in lower Indus plains than on mountain areas. In general, the toxic elements Cr, Mn, Co and Ni exhibited altitudinal trends (P < 0.05). The few exceptions to this trend were the higher values for all studied elements from the northern wet mountainous zone (low lying Himalaya). Spatial PCA/FA highlighted that the sources of different trace elements were zone specific, thus pointing to both geological influences and anthropogenic activities. The Hazard Index for Co and for Mn in children exceeded the value of 1 only in the riverine delta zone and in the southern low lying zone, whereas the Hazard Index for Pb was above the bench mark for both children and adults (with few exceptions) in all regions, thus indicating potential non-carcinogenic health risks. These results will contribute towards the environmental management of trace metal(s) with potential risk for human health throughout Pakistan. | Mercury (Hg) contamination in environmental matrices and associated human exposure has been recognized as a critical long-lasting issue worldwide. However, studies are still elusive that summarized the overall status of Hg pollution and its impacts on public health in Pakistan. Hence, this review encompasses the environmental prevalence, potential sources, and human exposure tendencies to Hg contamination in Pakistan. Reviewed literature revealed jolting levels of Hg in various environmental samples, such as dust, soil, water, and air collected from the residential and industrial areas. Inhalation of Hg via dust particle was identified as the primary pathway for human exposure, while atmospheric deposition and gold mining are identified as the two primary sources of Hg contamination in the environment. Considering human exposure, the highest bioaccumulation of Hg was ranged from 5885 to 8698 µg/kg in hair samples collected from the residents of the Kashmir Valley, Pakistan. However, in the lower Himalayan regions, including Islamabad and Swabi, the concentration of Hg in hair samples was reported at 1085 µg/kg, slightly beyond WHO devised reference dose (RfD) of Hg (1000 µg/kg). This review revealed the worst scenario of Hg contamination in human biomatrices and environmental compartments in Pakistan, which needed immediate rehabilitation measures. | The electrochemical nitrogen reduction reaction (NRR) as an energy-efficient approach for ammonia synthesis is hampered by the low ammonia yield and ambiguous reaction mechanism. Herein, phosphorus-doped carbon nanotube (P-CNTs) is developed as an efficient metal-free electrocatalyst for NRR with a remarkable NH3 yield of 24.4 μg·h−1·mg−1cat. and partial current density of 0.61 mA·cm−2. Such superior activity is found to be from P doping and highly conjugated CNTs substrate. Experimental and theoretical investigations discover that the electron-deficient phosphorus sites with Lewis acidity should be genuine active sites and NRR on P-CNTs follows the distal pathway. These findings provide insightful understanding on NRR processes on P-CNTs, opening up opportunities for the rational design of highly-active cost-effective metal-free catalysts for electrochemical ammonia synthesis. | eng_Latn | 28,063 |
The prototyping is to realize an original model quickly according to the communication between users and developers to improve the model quality and decrease the faults. According to analyzing the basic characteristics of the mining recycling economy, a spatial decision support system (SDSS) development strategy by using the prototyping is proposed to integrate the technologies of the rapid prototyping, ComGIS skills and DSS. A SDSS of mining recycling economy in Qiandongnan is designed as an example using prototyping as its main method, the basic frame has been finished, and the design of its function models and model base also defined. | The core of mining recycling economy is comprehensive utilization of mineral resources.It is the base of economical system of human being,and has a significant influence on economic development and environment change.On the other hand,the comprehensive utilization of mineral resources is restricted by technology and knowledge level of human being. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 28,064 |
In financial risk measurement, value-at-risk (VaR) and conditional VaR (CVaR) are two important risk measures. They are often estimated by Monte Carlo method combined with importance sampling (IS). Randomized Quasi-Monte Carlo (RQMC) method is an alternative technique, whose convergence rate is asymptotically better than the Monte Carlo method. This paper investigates the combination of IS and RQMC method. The main contribution is two-fold. First, we prove the consistency of the combined method for both VaR and CVaR estimations. Second, we establish error bounds for the CVaR estimate. Particularly, we show that under some mild conditions, the root mean square error of the CVaR estimate is $O(N^{-1/2-1/(4d-2)+\epsilon})$ for arbitrarily small $\epsilon>0$, where $d$ is the dimension of the problem. As a special case, these results also hold for plain RQMC estimates without using IS. | Indispensable for students, invaluable for researchers, this comprehensive treatment of contemporary quasi-Monte Carlo methods, digital nets and sequences, and discrepancy theory starts from scratch with detailed explanations of the basic concepts and then advances to current methods used in research. As deterministic versions of the Monte Carlo method, quasi-Monte Carlo rules have increased in popularity, with many fruitful applications in mathematical practice. These rules require nodes with good uniform distribution properties, and digital nets and sequences in the sense of Niederreiter are known to be excellent candidates. Besides the classical theory, the book contains chapters on reproducing kernel Hilbert spaces and weighted integration, duality theory for digital nets, polynomial lattice rules, the newest constructions by Niederreiter and Xing and many more. The authors present an accessible introduction to the subject based mainly on material taught in undergraduate courses with numerous examples, exercises and illustrations. | The contamination of soils by heavy metals is a current problem for agricultural production. Rapid access and reliability to heavy metal concentration such as cadmium is crucial for international trade. In the present study, visible and near infrared (VIS-NIR) spectroscopy, combined with linear and statistical methods, were used to predict the cadmium concentration of organic cocoa bean samples. Partial Least Square Regression (PLSR) and Support Vector Regression (SVR) were implemented to estimate the content of this heavy metal from hyperspectral imaging and chemical analysis. Competitive Adaptive Reweighted Sampling Method (CARS) and Jackknife method were used for selecting optimal wavelength. The SVR model performed satisfactorily with the use of 45 resulting wavelengths from optimization using CARS and the Jackknife method, with an adjusted coefficient for the test R2 of 0.9401 and an RMSEP of 0.2594. Based on the results, it was concluded that VIS-NIR spectroscopy combined with CARS-Jackknife methods seems to be a fast and effective alternative to classical methods for predicting the concentration of cadmium in organic cocoa beans. | eng_Latn | 28,065 |
Kawah Ijen volcano in East Java, Indonesia emits hyperacid (pH ≈ 0) brines rich in toxic elements including F, Al, Cd and Tl, which are transported downstream by the Banyu Pahit River, which is eventually used to irrigate farmland on the Asambagus Plain. The fate and behavior of major and trace elements are investigated, in the region of greatest change to the Banyu Pahit River, where thermal springs and the neutral Kali Sat and Kali Senggon Rivers increase its discharge 6-fold and pH increases from 1.9 to 4.5 with the development of abundant precipitates. The conservative behavior of Cl, F and SO 4 allows determination of the proportions of the mixing constituents at each confluence. Comparing a mass balance model based on the resulting proportions with measured concentrations demonstrates conservative behavior for most cations, with the exception of Si, Zr, Sn and Ba, which precipitate as amorphous silica, barite, and Zr and Sn phases, respectively. Iron is added as particulate Fe-(oxy)hydroxide in mixing with thermal spring outflow, and dissolves in the lower pH water. This also contributes Co, Cd, Mn, Y, and the rare earth elements, which are desorbed from the Fe-(oxy)hydroxide upon entering the acid water. Subsequent saturation in Fe-(oxy)hydroxide after mixing with the neutral rivers leads to a reverse response. Still, element behavior is close to conservative, which means that the volcanogenic toxic element load is almost entirely transferred to the Asambagus Plain with ensuing environmental and health impacts. This study shows that compositions of these acid waters can be understood and reproduced in a thermodynamic model, but only when fine-tuned using measured compositions and field observations. Therefore, the model’s utility in assessing the fate of toxic elements and in planning the environmental mitigation is limited. | Trace elements mean elements present at low concentrations (mg kg � 1 or less) in agroecosystems. Some trace elements, including copper (Cu), zinc (Zn), manganese (Mn), iron (Fe), molybdenum (Mo), and boron (B) are essential to plant growth and are called micronutrients. Except for B, these elements are also heavy metals, and are toxic to plants at high concentrations. Some trace elements, such as cobalt (Co) and selenium (Se), are not essential to plant growth but are required by animals and human beings. Other trace elements such as cadmium (Cd), lead (Pb), chromium (Cr), nickel (Ni), mercury (Hg), and arsenic (As) have toxic effects on living organisms and are often considered as contaminants. Trace elements in an agroecosystem are either inherited from soil parent materials or inputs through human activities. Soil contamination with heavy metals and toxic elements due to parent materials or point sources often occurs in a limited area and is easy to identify. Repeated use of metal-enriched chemicals, fertilizers, and organic amendments such as sewage sludge as well as wastewater may cause contamination at a large scale. A good example is the increased concentration of Cu and Zn in soils under long-term production of citrus and other fruit crops. Many chemical processes are involved in the transformation of trace elements in soils, but precipitation–dissolution, adsorption–desorption, and complexation are the most important processes controlling bioavailability and mobility of trace elements in soils. Both deficiency and toxicity of trace elements occur in agroecosystems. Application of trace elements in fertilizers is effective in correcting micronutrient deficiencies for crop production, whereas remediation of soils contaminated with metals is still costly and difficult although phytoremediation appears promising as a costeffective approach. Soil microorganisms are the first living organisms subjected to the impacts of metal contamination. Being responsive and sensitive, changes in microbial biomass, activity, and community structure as a result of increased metal concentration in soil may be used as indicators of soil contamination or soil environmental quality. Future research needs to focus on the balance of trace elements in an agroecosystem, elaboration of soil chemical and biochemical parameters that can be used to diagnose soil contamination with or deficiency in trace elements, and quantification of trace metal transport from an agroecosystem to the environment. r 2005 Elsevier GmbH. All rights reserved. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,066 |
This paper describes the environmentally geochemical characteristics of heavy metal pollutants such as Cu and Zn in the surficial soil of Guiyang, the capital city of Guizhou Province. The baseline concentrations of heavy metals in soil and the geochemical norms have been established to distinguish natural or artificial influence on the environment. Using the statistically analytical methods, we have established the baseline of Cu in Guiyang (18.8 mg/kg) and the soil (over 68.4 mg/kg) may suffer Cu contamination. The data of Zn are 46.3 mg/kg and 112.0 mg/kg. Geoaccumulation index analysis indicated that the surficial soil that has suffered non-pollution to mid-pollution of Cu accounts for 38%, 38%, and 22% for mid-pollution, and only 2% between mid-pollution to severe pollution. Surficial soil that has suffered non-pollution to mid-pollution of Zn accounts for 41%, 50%, and 7% for mid-pollution, and only 2% between mid-pollution to severe pollution. The maximal degree of Cu contamination is 5.09 in the surficial soil of Guiyang. Surficial soil that has not suffered Cu pollution accounts for 53.2%. The total pollution degree of Cu is slightly over zero. So the surficial soil of Guiyang has suffered slight Cu pollution. The maximum value of Zn contamination degree is 2.85 in the surficial soil of Guiyang. 77.8% of the surficial soil has not yet suffered any Zn pollution. The total pollution degree of Zn is less than zero. So the surficial soil in Guiyang is free from pollution of Zn. | An abnormal heat island, in which genesis is totally different from that of a normal heat island, exists in typical karst city Guiyang in southwestern China and dominates its regional thermal environment. Based on Landsat enhanced thematic mapper plus images and moderate-resolution imaging spectroradiometer land surface temperature products, the abnormal heat island in this area is accordingly extracted. Through overlaying and statistic analysis in geographic information system, this paper studied the relationship among the abnormal heat island and karst distribution, vegetation coverage, and temperature difference at day and night with the following results: nearly 70% of the abnormal heat island distributes in karst and semi-karst areas, 95.7% of abnormal heat islands mainly distribute in region of low-vegetation coverage (percentage of vegetation lower than 45%); 82.28% of abnormal heat islands are in regions where the temperature difference between day and night is over 14°C. The results show that the formation of an abnormal heat island largely depends on rock types and the area of bare rock. | A solvent-free approach for the regioselective synthesis of β-amino alcohols inshorter reaction times and higher yields, compared to conventional heating is described. Itinvolves microwave (MW) exposure of undiluted reactants in the presence of sulphatedzirconia (SZ) or sulphated zirconia over MCM-41 (SZM) as catalyst. Both acid materialscan be easily recovered and reused. | eng_Latn | 28,067 |
Inorganic contamination in groundwater has become a major health concern because of its acute and chronic health impacts. To investigate the major hydro-geochemical processes controlling groundwater quality in a part of the Indus river basin, 29 groundwater samples were collected and tested for major ions and potentially harmful elements (PHEs) including Mn, Cu, Cd, Cr, Pb, Fe, and Zn. The cations and PHEs were measured using the atomic absorption spectrophotometer and the anions were analyzed using ion chromatograph. Anthropogenic activities and rock–water interactions are the major factors controlling groundwater quality, along with silicate weathering and evaporation. Ca–HCO3 is the dominant water facies, followed by Na–HCO3 and Na–Cl water facies. Among PHEs, Pb is the most dominant contaminant with 21 samples exceeding WHO guidelines followed by Cr and Fe in 27% and 24% of samples, respectively. Health risk to the population for both dermal and direct ingestion was assessed by calculating chronic dose index (CDI), hazardous quotient (HQ), and hazardous index (HI) for children and adults. HQ through ingestion was highest for Cd because of its low reference dose value. HI for dermal exposure was found to be safe for both children and adults, with values below 1; for ingestion 14 samples had high HI > 1 for adults, and 27 samples for children. High HI values indicate that at a few locations, the groundwater is not suitable for consumption and can cause serious health implications. Proper planning for mitigation is required and large-scale testing along with sharing of wells among neighbors is recommended for reducing exposure. | Eighty samples of sandy substrate were collected in November 2002 and 2003, from 20 municipal playgrounds in Madrid (Spain) to assess the potential adverse health effects of the exposure of children to trace elements in this material during their games. In each playground, two 500 g samples were collected, dried at 45 °C for 48 h, sieved below 100 μm, acid digested and analyzed by ICP-MS. Doses contacted through ingestion and inhalation and the dose absorbed through the skin were calculated using USEPAs hourly exposure parameters for children and the results of an in situ survey. The toxicity values considered in this study were mostly taken from the US DoEs RAIS compilation. The results of the risk assessment indicate that the highest risk is associated with ingestion of soil particles and that the trace element of most concern is arsenic, the exposure to which results in a cancer risk value of 4.19 × 10 −6 , close to the 1 × 10 −5 probability level deemed unacceptable by most regulatory agencies. Regarding non-cancer effects, exposure to playground substrate yields an aggregate Hazard Index of 0.28, below the threshold value of 1 (with As, again, as the largest single contributor, followed by Pb, Cr, Al and Mn). Although the uncertainties associated with the estimates of toxicity values and exposure factors should be reduced before any definite conclusions regarding potential health effects are drawn, risk assessment has proven to be a very useful tool to identify the contaminants and exposure pathways of most concern in urban environments. | We report enhancement of the mechanical stability of graphene through a one-step method to disperse gold nanoparticles on the pristine graphene without any added agent. | eng_Latn | 28,068 |
Due to the existence of a hard and massive roof (HMR), severe ground pressure behaviors have been observed at the working face, resulting in safety issues and the degradation of production effectiveness. Based on the HMR conditions of the Datong Mining Area, the fracture-related instability of the HMR and its effects on the support selection were investigated by analyzing the interaction between support and overlying strata. Advancefixed-distance presplitting blasting (AFPB) technology was proposed to control the caving interval of HMR, and the influence of the controlled interval on the working load of supports was also analyzed. The working load of the support and the caving interval of the HMR were determined based on the controlled HMR fracture technology, and these were verified by field application tests. The working resistance of the support and the step distance were determined based on controlled roof fracture and were verified by on-site application experiments. The results revealed that cracks emerged after the presplitting blasting, resulting in significantly reduced strata behaviors. Furthermore, the support exhibited good adaptability. | This study investigates the flow and caving characteristics of top coal and roof rock, as well as top coal loss pattern in the fully mechanized top coal caving mining of extra thick coal seams. The two dimensional discrete element numerical simulation software program, particle flow code (PFC), is used for the simulation of top coal caving and the inversion analysis. The original locations, distribution, and migration pattern of caved top coal and lost coal were obtained. The analysis shows that in the initial site of caving, the caved bodies are in the form of arc shaped strips in front of the working face. During the caving, caved bodies of different heights move towards the lower rear of the face at different speeds. The lost coal and caved roof rock are originally located at the interface between coal seam and roof, the lost coal is mainly distributed in the goaf on the floor. Behind the support, the caved top coal bodies originally are arc shaped strips, with the highest points located at the midline of the caving opening. The strips are more curved near the goaf than those near the support. During top coal caving, the strips successively cave, with the adjacent outer strip replacing the caved one. The variations of top coal loss and waste rock ratio with time reflect the different phases of top coal caving. In order to improve coal recovery and limit the amount of caved roof rock, the waste rock ratio should be controlled below 10 %. When the waste rock ratio reaches this value, the caving opening should be closed. This paper provides theoretical bases for the improvement of top coal recovery in the fully mechanized top coal caving mining of extra thick coal seams. | ABSTRACTUNC-45A is an ubiquitously expressed protein highly conserved throughout evolution. Most of what we currently know about UNC-45A pertains to its role as a regulator of the actomyosin system... | eng_Latn | 28,069 |
The epiphytic lichen Lecanora conizaeoides was used as a monitor organism of airborne metals around an industrial area (a steelworks and an iron foundry) at Frederiksvaerk, Denmark. Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, V and Zn were determined by atomic absorption spectrophotometry and K and Na by flame emission techniques. SO 2 air pollution levels were estimated by the distribution of lichen species with different SO 2 sensitivities. A similar regional variation was found within the Frederiksvaerk area of concentrations of the heavy metals Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn, showing increasing concentrations in Lecanora conizaeoides towards the pollution sources. The order of the maximum enrichment factors was: Cd 74, Pb 62, Cu 35, Cr 34, V 31, Fe 28, Mn 28, Zn 26 and Ni 9. The air pollution in the area results in elevated concentrations of heavy metals in Lecanora conizaeoides within a radius of at least 3 km from the industrial area. | The following study was designed to determine the environmental impact of pollutants emitted by combustion of heavy fuel oil in Ashdod, in Southwestern Israel. For this purpose we measured concentrations of total S, V, and Ni in the local epiphytic fruticose lichen Ramalina duriaei, which grows in the peripheral region of the town, and compared these results with those obtained in thalli collected 100 km away, in the HaZorea Forest, northeastern Israel. We also transplanted thalli from the HaZorea Forest to the Ashdod region for a 10-month period. At the end of the experiment we measured the elemental content in all samples. In addition we measured chlorophyll degradation expressed as changes in the 435 nm/415 nm OD ratio, and changes in the spectral response of the thalli. In several sites in the Ashdod region we found high concentrations of S, V, and Ni in transplanted thalli, which correlated with the NDVI values. These findings agree with other measurements of SO 2 and V in the Ashdod area. We suggest that a high V/Ni ratio in lichens is a tracer for air pollution caused by the combustion of heavy fuel oil. | Accumulation of Zn, Cu, Pb and Cd was studied in snails fed for 120 days on diets contaminated with each metal separately and with all metals mixed together. The concentrations of Zn in food were in the range 39 to 12 200 mg kg −1 , Cu 9–1640 mg kg −1 , Pb 0.4–12 700 mg kg −1 , and Cd 0.16–146 mg kg −1 on a dry weight basis. At the highest concentrations of all metals the consumption rates decreased significantly. For the remaining concentrations, Zn and Cu were accumulated in soft tissue in proportion to their concentrations in food. The lowest treatments of Pb and Cd did not cause any increase in soft tissue concentrations of these metals but at average treatments, a clear increase was observed. Copper was accumulated especially efficiently, exceeding concentrations in food throughout the whole range of treatments. Except for the lower end of experimental treatments, Zn was accumulated approximately in direct proportion to its concentration in the diet. Lead was the most efficiently regulated metal, with soft tissue concentrations always substantially lower than in food. Approximately 60% of Zn, 90% of Cu, 43% of Pb and 68% of Cd on average was assimilated from food. The assimilation efficiency of food alone was ca 74%. The concentrations of metals in shells increased significantly with exposure, but (with one exception) the concentrations in shells did not exceed 5% of those found in soft tissue. We argue that snails are more important as agents of food-chain transport of Cu and Cd, than of Zn or Pb. Our results indicate also that snails are not able to deposit significant quantities of metals in their shells, at least during the time scale of our laboratory experiment. | eng_Latn | 28,070 |
The paper presents the results of 210 Po determinations, and 210 Po / 210 Pb activity ratios, in the tissues and organs of the Baltic crustacean Saduria entomon. Additionally, the subcellular localisation of 210 Po in the hepatopancreas of this organism has been studied using centrifugation followed by determination of the 210 Po concentrations in isolated fractions. The 210 Po concentrations fall within the range 0.63–543.5 Bq kg−1 (dry wt). The highest values of 210 Po and 210 Po / 210 Pb activity ratio (10.6) were found, as expected, in the hepatopancreas. The majority of the 210 Po in the hepatopancreatic cells was found in the cytosol fraction (60% of the total 210 Po ). | To determine radioactivity and trace metal levels, surface sediments were collected from two important areas (Izmir Bay and Didim) in the Aegean Sea region of Turkey, and were analyzed for concentrations of 210Po, 210Pb and trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn). The average 210Po and 210Pb massic activities in sediments varied in the range of 24 ± 5 to 126 ± 6 Bq kg−1 dry wt. and 18 ± 3 to 59 ± 4 Bq kg−1 dry wt., respectively. Izmir Bay exhibited the highest polonium activities in sediments, likely due to specific sedimentation processes and other sediment characteristics. The trace metal results showed that the Izmir Bay is facing trace metal pollution. The metal concentrations in sediment samples are low compared to those from the other neighboring marine environments. | We demonstrate a real-time 25-Gb/s PON prototype with ethernet-PON MAC/PHY, O-band transmitter, and cost-effective APD receivers. With applying parasitic inductance and capacitance reduction, the frequency response of 25-Gb/s APD ROSA with TO46-pacakge is improved to support high receiver sensitivity around −25 dBm at the BER of 10−3. The 30 dB power budget of 25 Gb/s downstream is achieved at the BER of 10−3. With long-term ethernet packet transmission, 25 Gigabit and 10 Gigabit ethernet traffics are successfully transmitted through the 20-km SMF over 14 hour’s observation window. Furthermore, QoS and bandwidth re-assignment function of the 25-Gb/s PON prototype are successfully demonstrated with respect to residential, business and mobile backhaul services in ONUs. | eng_Latn | 28,071 |
Federal law requires mine operators to salvage and respread topsoil on the surface of minesoils as part of the reclamation process. Guidelines are needed to ensure that the best available topsoil is obtained and used. The productivity and land use capability of minesoils must compare favorably with premining conditions. Guidelines for rating the quality of cover soil and the agricultural capability of minesoils are proposed. (24 references, 5 tables) | A waste rock characterization effort was designed and implemented to identify favorable waste rock borrow material for use as rock armor on a tailing impoundment side-slope reclamation project. The following criteria were applied: 1) sufficient volumes of material; 2) particle size distributions with greater than 50% of the material larger than 12.5-mm particle diameter; 3) acid-base accounting showing positive net neutralization potential; and 4) sufficient nutrient levels and minimal potentially phytotoxic elements to facilitate revegetation. In addition, a field-scale erosion test designed to simulate a 100-year, 24-hour storm event was conducted to determine the efficacy of the selected rock material and of selected ripping treatments in controlling erosion. Two generally non-acid generating and erosion resistant mine-waste rock types were found: argillite and arkose material. Within the potential source areas, evidence of oxidation (yellowish-red staining) was a good predictor of net acid -generating material and used as exclusion criteria. Argillite was used as rock armor on short slopes and the coarser arkose material for slope-lengths greater than 90-meters. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 28,072 |
Mercury (Hg) is a toxic element that is emitted to the atmosphere through human activities, mainly fossil fuel combustion. Hg accumulations in soil are associated with atmospheric deposition, while coal-burning power plants remain the most important source of anthropogenic mercury emissions. In this study, we analyzed the Hg concentration in the topsoil of the Kozani-Ptolemais basin where four coal-fired power plants (4,065 MW) run to provide 50 % of electricity in Greece. The study aimed to investigate the extent of soil contamination by Hg using geostatistical techniques to evaluate the presumed Hg enrichment around the four power plants. Hg variability in agricultural soils was evaluated using 276 soil samples from 92 locations covering an area of 1,000 km(2). We were surprised to find a low Hg content in soil (range 1-59 μg kg(-1)) and 50 % of samples with a concentration lower than 6 μg kg(-1). The influence of mercury emissions from the four coal-fired power plants on soil was poor or virtually nil. We associate this effect with low Hg contents in the coal (1.5-24.5 μg kg(-1)) used in the combustion of these power plants (one of the most Hg-poor in the world). Despite anthropic activity in the area, we conclude that Hg content in the agricultural soils of the Kozani-Ptolemais basin is present in low concentrations. | This study characterized and mapped the spatial variability patterns of seven soil heavy metals (Cd, Cr, Cu, Hg, Ni, Pb and Zn) for further environmental monitoring, remediation and planning by multivariate geostatistical methods, to delineate sources of soil heavy metals in a rice paddy field in the north of Changhua County, Taiwan. The variograms and cross-variograms of soil heavy metals were modeled in three spatial structures which included the nugget effect and two spherical models with ranges of 288 and 1,200 m for short-range and long-range spatial scales, respectively. Multivariate spatial variations of soil heavy metals can be detected using factor analysis based on coregionalized coefficient matrices for different scales. Moreover, the multivariate geostatistical analysis results indicated that factor loadings of the regionalized factors of soil heavy metals changed depending on the spatial scale. The loadings of each factor became stable for distances larger than 1,200 m. The maps of spatial components of soil heavy metals reveal that the short-range variation sources of Cd, Cr, Cu, Ni and Zn were highly correlated to the industrial plants in this study area. The long-range variations of Cd, Cr, Cu, Ni and Zn strongly corresponded to the locations of irrigation systems and industrial plants. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,073 |
A series of field and laboratory experiments were conducted during 1994–996 to study the seasonal changes in sewage sludge characteristics and to evaluate the effect of sludge treatment processes and their application to sandy soil on soil-plant heavy metal contents and the numbers of some pathogenic microorganisms in both treated sludge and sludge provided soils. Results of seasonal production of sludge showed wide variation in their chemical and microbiological characteristics. Lime application resulted in an increase in the pH values and temperature degrees. The maximal values of temperature and pH were obtained when sludge treated with 20% lime. No big difference was observed between the sludge treatments received lime at rates of 10, 15, and 20% lime. The 10% limed-sludge treatment was the best for reducing concentrations of heavy metals and numbers of bacterial pathogens in sludge. Stoping addition of sludge to soil for one cropping season after continuous sludge addition for four seasons s... | Cadmium (Cd) is a non-essential heavy metal that is recognized as a major environmental pollutant. Cd enters the ecosystem chiefly as the result of human activities. Present investigation was conducted to assess the biochemical and physiological responses of rice to different concentrations of Cd. Seeds of rice were sterilized and were allowed to germinate under various Cd concentrations. Cadmium caused a gradual decrease in vigor index, root length, shoot height and amylase activity. Germination indexes of treated seeds were decreased. Root length decreased under all treatments. Cadmium uptake by seedlings increased with increasing Cd concentration and followed Michaelis-Menten kinetics. The average total amylolytic activities of rice seeds did not have a significant change in less than 4mg Cd l-1 medium compared to the control, but activity was progressively depressed with increasing concentration of Cd (6–10 mg l-1). Antioxidative responses of rice seedlings were also explored. Antioxidant enzyme activity in rice leaves generally showed no significant changes at low levels of Cd exposure. But high levels of Cd stimulated enzyme activity. These results suggested that prompt antioxidative responses might be necessary for the reduction of Cd-induced oxidative stress in roots but not in leaves. | Lime treatment is a well-known technique to improve the mechanical response of clayey subgrades of road pavements or clayey soils used for embankment. Several studies show that lime treatment significantly modifies the physical and hydromechanical properties of compacted soils. Nevertheless, studies on the scale effect under climatic changes are scarce. Actually, wetting–drying cycles might significantly modify the microstructure of treated soils, giving rise to changes in hydromechanical properties. This modification could be dependent on the size of soil aggregates before lime treatment. In the present work, this scale effect was studied by investigating the stiffness of a compacted lime-treated clayey soil using bender elements. The studied soil was first air-dried and ground into a target maximum soil aggregates size (Dmax). For each aggregate size, the soil was humidified to reach the target water contents wi, then mixed with 3% of lime powder (mass of lime divided by mass of dried soil) prior to the... | eng_Latn | 28,074 |
Environmental pollution occasioned by artisanal activities and technical failures at exploration sites has affected mostly oil producing and other mineral resources mining regions in developed and developing nations. As conventional techniques of remediation seem to be progressively unreliable and inefficient, contaminated land management experts have adopted a plant-based technology described as ‘phytoremediation’ for effective detoxification and removal of contaminants in substrate environmental media (soil and sediment). This technique, has gained public acceptance because of its aesthetic, eco-friendly, solar energy driven and low cost attributes. With complexity of environmental pollution in Africa, identification of appropriate remediation approach that deliver net environmental benefit and economic profit to the society is vital, while also focusing on the exploitation of plants genetic tools for more clarity on phyto tolerance, uptake and translocation of pollutants. In this article, we reviewed the status, progress and challenges of phytoremediation in selected African countries (South Africa, Nigeria, Tanzania, Zambia, Egypt and Ghana), the ecological impact of the pollutants, phytoremediation strategies and the possible plants of choice. Besides highlighting the support roles played by soil fauna and flora, the fate of harvested biomass/dieback and its future prospects are also discussed. We further explored the factors challenging phytoremediation progress in Africa, amidst its promising potentials and applicability for sustainable ecosystem management paradigm. | Mine tailings, generated from the extraction, processing, and utilization of mineral resources, have resulted in serious acid mine drainage (AMD) pollution. Recently, scholars are paying more attention to two alternative strategies for resource recovery and ecological reclamation of mine tailings that help to improve the current tailing management, and meanwhile reduce the negative environmental outcomes. This review suggests that the principles of geochemical evolution may provide new perspective for the future in-depth studies regarding the pollution control and risk management. Recent advances in three recycling approaches of tailing resources, termed metal recovery, agricultural fertilizer, and building materials, are further described. These recycling strategies are significantly conducive to decrease the mine tailing stocks for problematic disposal. In this regard, the future recycling approaches should be industrially applicable and technically feasible to achieve the sustainable mining operation. Finally, the current state of tailing phytoremediation technologies is also discussed, while identification and selection of the ideal plants, which is perceived to be the excellent candidates of tailing reclamation, should be the focus of future studies. Based on the findings and perspectives of this review, the present study can act as an important reference for the academic participants involved in this promising field. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,075 |
Two field trials were conducted to study the rate of release of nutrients and heavy metals from wood and peat ash fertilizers in forest soils. In the first experiment, ash particle residues were extracted from peat and mineral soils 3 and 5 years after spreading and analysed for changes in element concentrations. Dissolution of different ash fertilizer products was also estimated by measuring the changes over time in the recovery of added nutrients and heavy metals in the surface of two peat soils. The results showed that potassium (K), sodium (Na), boron and sulfur are easily released from wood ash, whereas heavy metals are highly insoluble in all types of ash fertilizer products. Granulated ash fertilizers were less soluble than powdered fertilizers and the products stabilized by self-hardening. Minor differences occurred in ash fertilizer dissolution between peat and mineral soils and soils of different fertility. The most significant difference between wood and peat ash concerning their dissolution wa... | In this study the most important chemical and physical properties of three kinds of fly ash originating from the circulating fluidized boiler incinerating agriculture and forest residues (i.e.rice husk, straw, wood chips, sawdust and bark) at a power plant (12+15MW) in Jiangsu province of China is determined. The study clearly show that fly ash is fine (0.001–0.2 mm), and have poor specific surface area (about 5 m2/g). The mineral composition is SiO 2 , CaCO 3 , KCl. The fly ash is strong alkaline, and nutrient elements are enriched in the fly ash. The total concentrations of Cd, Hg, Pb below the limit values, therefore the fly ash can be used as fertilizer, but care should be taken. | We have found that Zn2+ prevented lysis of unfertilized sea urchin eggs, and the eggs retained the ability to form fertilization membranes and to divide. SDS polyacrylamide gel electrophoresis showed that proteolysis of several proteins accompanied egg lysis, but Zn2+ inhibited this proteolysis. Therefore, Zn2+ blocks protease activity directly or indirectly and thereby prolongs the longevity of unfertilized sea urchin eggs. | eng_Latn | 28,076 |
Multi-element soil analysis is now an established technique in archaeology. It has been used to locate archaeological sites and define the extent of human activity beyond the structural remains, and to aid interpretation of space use in and around archaeological remains. This study aimed to evaluate the consistency of these soil element signatures between sites and hence their potential usefulness in archaeological studies. Known contexts on abandoned farms across the UK were sampled to test the relationships between element concentrations and known functional area and to assess inter-site variability. The results clearly show that there are significant differences in the soil chemistry of contrasting functional areas, particularly for Ba, Ca, P, Zn, Cu, Sr and Pb. Despite significant site specific effects, which appear to reflect individual anthropogenic practices rather than geological influences, there is sufficient similarity in the pattern of element enhancement to allow reliable interpretation of former function using discriminant models. Relating these enhancements to precise soil inputs, however, is more problematic because many important soil inputs do not contain distinct element fingerprints and because there is mixing of materials within the soil. There is also a suggestion that charcoal and bone play an important role in both the loading and post-depositional retention of Ca, Sr, P, Zn, and Cu and thus may be significant in the formation of soil element concentration patterns. | Results from soil chemical analysis have demonstrated enhanced concentrations of lead (Pb) associated with archaeological sites. However, interpretation of these Pb concentrations is difficult because of the multitude of possible Pb sources. This pilot study of an abandoned croft in Shetland suggests that Pb isotope ratios have the potential to identify sources of anthropogenic Pb. The results highlight two different Pb associations. The first includes hearth, house floor and house overburden soils, with end members of fuel materials and an unidentified material with a low (< 1.126) 206 Pb/ 207 Pb ratio. The second includes byre, kailyard (garden) and arable soils, with end members of hearth materials and local wind-blown sand. | Background ::: Serum calcium (Ca) and inorganic phosphate (Pi) concentrations and calcium-phosphate product (CPP) levels are positively associated with worse outcomes in patients with chronic kidney disease, but there are few data for Pi or Ca and none for CPP in patients with chronic heart failure (CHF). | eng_Latn | 28,077 |
This study investigates the impact of accidental fires and the record of recent environmental change held within a long peat core taken on Burbage Moor in the south Pennines (UK). The core has been subjected to mineral magnetic, heavy metal (via inductively coupled plasma–optical emission spectroscopy) and radiometric analyses. It may be subdivided into three zones reflecting the infilling of a basin-like depression and reveals pre-industrial conditions and the impact of recent atmospheric particulate pollution. Peak concentrations of heavy metals are relatively high (e.g., peak Pb concentration is 1,124 mg kg−1). However, the mineral magnetic and heavy metal depth profiles may have been affected by post-depositional changes. The core has been influenced by drainage and a number of moor fires. The area was extensively burnt in 1976, though assessing the impact of this event is problematic, due to the perturbed nature of the profile and the inability to provide a reliable chronology. | The contents and profile distributions of Cr, Ni, Cu, Zn, Cd, Hg, Pb, and benzo[a]pyrene in oligotrophic peat soils, oligotrophic peat gley soils (Dystric Fibric Histosols), humus-impregnated peat gleyzems (Dystric Histic Gleysols), and mucky gleyzems (Dystric Gleysols) have been analyzed with consideration for their degree of oligotrophicity and anthropogenic loads. Horizons with the accumulation (O, Tpyr, TT) and removal (Ghi,e) of heavy metals have been revealed. The increase in the content of heavy metals and benzo[a]pyrene in the upper layer of oligotrophic peat soils under technogenic fallouts in the impact zone of flare and motor transport has been considered. Statistical parameters of the spatial variation of parameters in organic and gley horizons have been calculated. The variation coefficients of pollutant elements (Pb and Zn) in the surface horizons of soils increase to 100–125%. Positive correlations revealed between the content of some heavy metals in litter indicate their bioaccumulation and possible joint input with aerotechnogenic fallouts. No correlations are found between the contents of benzo[a]pyrene and heavy metals, but a reliable negative correlation with the ash content is noted in the peat horizon. | Ti-based bulk metallic glasses (BMGs) are very attractive for applications because of their excellent properties such as high specific strength and high corrosion resistance. In this paper, we briefly review the current status of the research and development of Ti-based bulk metallic glasses. Emphasis is laid on glass-forming ability, mechanical properties, corrosion resistance, and biocompatibility. | eng_Latn | 28,078 |
Groundwater samples from different regions of Tripoli city (Libya) were analyzed for environmental control purposes. The concentrations of several trace elements (As, B, Ba, Be, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Sb, Sr, and Zn) were determined by means of ICP‐OES and AAS methods. The obtained results were also compared with the European and Canadian standards, as well as with the Egyptian ground, Nile, and drinking water concentrations. As a result, the detected elements were classified into three different groups. The first group of elements, (Na and Sr) was found to have high concentrations. The second group of elements, (Ba, B, Ca, Cr, Cu, K, Li, Mg, and Zn) had comparable concentrations. The third group of elements, (As, Cd, Fe, Mn, and Sb), showed low concentrations. The observed high concentrations of some elements, in particular Sr, and the lower concentrations of the others, such as Fe and Mn are relevant to their levels in Tripoli city soils. In addition to the above elements, some inorganic ions, (NH4 +, NO2 −, and NO3 −) were also detected using ion chromatography (IC). The elevated concentration of NO3 − is mainly due to various industrial activities, the use of fertilizers, and/or pollution from sewage. The concentration of the other inorganic ions, (NH4 +, NO2 −) was found to be within the international standard limits. The natural radioactivity in the samples has also been investigated using γ‐spectrometry and was found to be very low. | Elemental analysis of soils from two different arable regions in Libya was carried out to measure the level of many trace elements. Instrumental neutron activation analysis was used for the determination of 10 elements, viz., (Ba, Ce, Co, Cr, Cs, Fe, Sc, Se, Th, and Zn), using their long-lived radionuclides. The accuracy of the measurements has been evaluated by analyzing two IAEA soil reference materials: IAEA Soil-7 and IAEA leak sediment SL-1; precision has been estimated by triplicate analysis of the sample and that of the reference material. Irradiations were carried out at the Tajura Research Center reactor, at 5-MW power level. It is clear that in the Libyan soil selenium concentration is somewhat lower than in other countries. The results show that trace metal concentrations in Libyan clay surface soil are higher than the sandy soil. | The present study aimed to assess the level of metal ions [chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn)] in the serum of patients with fixed orthodontic appliances. One hundred samples (32 males, 68 females) were collected from patients undergoing fixed orthodontic treatment for different periods. A reference (control) group (24 males, 16 females) who had no appliances was used to properly evaluate the changes in the level of these elements in orthodontic appliance users. The element concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS). Higher concentrations of metal ions (except for Cr) were found in the serum of the orthodontic group. Bivariate scatter plot showed a highly significant (p < 0.001) correlation between Ni and other elements. The duration of orthodontic treatment increased significantly the Ni levels whereas the bracket type was found to have no significant impact on altering the concentration level of metal ions. The results of the SEM-EDS showed a high variation in the level of metal ions in the brackets and wires. In conclusion, fixed orthodontic appliances increased serum levels of Ni, Zn, Mn, Fe, and Cu but did not change Cr levels. | eng_Latn | 28,079 |
Trace metals that are mobilized during early diagenesis can be coprecipitated with and adsorbed on authigenic sulfide minerals in anoxic sediments. A major portion (generally > 60%) of the non-silicate bound fraction of potentially toxic metals, such as As, Cu and Hg, is commonly coprecipitated with pyrite near the sediment-water interface. Traditional methods (e.g. 1 N HCl or citrate dithionite extractions) for determining the concentration of potentially bioavailable metals in sediments do not include the pyrite bound fraction. However, pyritized metals can be potentially bioavailable if the pyrite is oxidized. Pyrite oxidation commonly occurs during sediment resuspension, seasonal migration of the redoxocline in sediments and when dredge spoils are dumped on land. Experimental measurements of metal release from pyrite, in initially anoxic sediments exposed to oxic seawater, indicate that a major portion (20% to over 90%) of the pyrite bound metals can be released in a day or less. The As, Cu and Hg released from pyrite usually exceeds the concentration of their potentially bioavailable fraction determined by traditional methods. Consequently, the pyritization-depyritization of trace metals is probably an important process in controlling the bioavailability of many important trace metals. | Pollutants have a tendency to sequestrate into remote sites in different environmental matrices thereby reducing the level of available fraction for uptake in living organisms. We examined availability of metals by subjecting soil and rice plant samples from Ishiagu mining district to a sequential extraction procedure and subsequently analyzed the extracts using Atomic Absorption Spectrophotometer (AAS). Our results revealed that metals were moderately available in samples in the following decreasing order: Zn>Pb>As>Cd>Se>Cu. Though metal levels differed in rice plant samples compared to soil, we noted also that availability of these pollutants varied spatially among various study locations. Based on available acceptable range, copper and zinc were within tolerable limits while cadmium was in excess in some study locations. On the other hand, levels of lead in rice plant samples exceeded acceptable limits. Considering the levels reported from different locations, it is possible that metals were immobilized in soil organic matter or trapped in other forms. Though in general metal levels were within acceptable limits in our study locations, we recommend that deliberate steps be taken by authorities to curtail indiscriminate mining activities capable of polluting soils and farm lands. For this reason, farmers should be encouraged to plant safe cultivars since this rice variety is a known poor metal accumulator. Keywords: Heavy Metals, Soil, Rice Plants, Ishiagu, Mining District | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 28,080 |
TRANSPORT PHENOMENA IN THE MIXED STATE AND FLUCTUATION REGIME IN (Bi1.6Pb0.4)Sr2Ca1-xHox(Cu1-yZny)2O8+d | Measurements of the magnetoresistivity, Seebeck, Nernst and Hall coefficients in Bi:2212 superconductors doped with Ho and Zn are reported. The critical temperature and the transport coefficients depend strongly on the Ho and Zn contents. The tails of the transport coefficients versus temperature curves are caused by fluctuation effects, which increase with increasing magnetic field. An anomalous suppression of superconductivity at x = 0.25–0.35 and y = 0.025–0.032 was also found when the hole concentration per Cu is PH = 1/8 and the transport properties exhibit metallic behavior. It was found that dBc2/dT = -2.4 ± 0.2 T/K, corresponding to a Ginzburg–Landau coherence length ξ = 15 A. The Hall resistivity ρxy scaling with the longitudinal resistivity ρxx as with α ≈ 1.8 is in agreement with the theory of Vinokur et al. The experimental data in the mixed state are in agreement with the prediction of the time-dependent Ginzburg–Landau theory. | This article discussed the distribution of major and trace elements of peat in Yuanchi,Changbai Mountain.Four profiles were collected with Wardenaar peat sampler produced in Netherlands.Each sample was cut into 1～2 cm at the present.As far as the special physical conditions in Yuanchi are concerned,the content of major and trace elements(Na、K、Mg、Ca、 Al、Ti、Fe、Mn、Zn、Pb、Cu)were determined among different peat bogs.The elements distribution with depth in each peat profile was fully analyzed.Also we have analyzed the enrichment of different elements in peat profiles.Through the calculated M/Ti(M refers to Na、K、Mg、Ca、 Al、Ti、Fe、Mn、Zn、Pb、Cu) ratio,compared with ratio of M/Ti collected from literature,we concluded the differences among different peat bogs.The increasing content of Mn、Zn and Pb from bottom to top in peat profiles proves the increasing pollution of them in present environment,which has profound implications for environment. | yue_Hant | 28,081 |
Sequential effects of cadmium on plant growth, biochemical and cyto-physiological aspects, antioxidant activity, and molecular screening of protein by SDS-PAGE in Trigonella | The present study was designed to investigate the effects of cadmium (Cd) on biochemical, physiological and cytological parameters of Trigonella treated with six different concentrations 0, 25, 50, 75, 100, or 125 ppm of metal. Germination%, root-shoot length, pigment, proline, and protein content showed a continuous decrease with increasing Cd concentrations and the maximal decline was observed at the higher concentration while the frequency of chromosomal aberrations rose with increasing metal concentration. Malondialdehyde content was found to be two-fold higher than control at 125 ppm Cd. On other hand the activities of superoxide dismutase (SOD) and glutathione peroxidase (GDP) rose more than two-fold and the peaked at 75 ppm of Cd. Thus, SOD and GDP were more sensitive to Cd than other involved in reactive oxygen species quenching mechanism. Additionally protein profiling by SDS-PAGE revealed that there was 89% polymorphism and considerable inter-specific variation in the analyzed accessions. Variat... | The contents of Hg,Cd,Pb,Cu,As,Cr and Zn in the surface sediments of the Changjiang River,Qinhuai River and Xuanwu Lake in Nanjing were monitored.The accumulation of metals were analyzed.The ecological risk was assessed by the potential ecological Hakanson index.The results showed that the potential ecological risk of heavy metals in surface sediments from Changjiang River and Xuanwu Lake was lower,but the risk of heave metals in surface sediments from Qinhuai River was high.Cd was the most hazardous element with the ecological risk index of 3.18 in Changjiang River,which belonged to middle ecological risk;Hg was the most hazardous element with the ecological risk index of 3.33 in Xuanwu Lake,which belonged to middle ecological risk,and other elements had low ecological risk.The potential ecological risk of heavy metals decreased as: HgCdCuAsZnPbCr in Qinhuai River.The element of Hg and Cd belonged to high ecological risk,and other elements belonged to low ecological risk. | eng_Latn | 28,082 |
Application of element extension model to comprehensive utilization effect evaluation of iron ore ttailings | Iron ore tailings is dressing the back out waste,The unreasonable way has caused huge waste of resources and environmental pollution,so it is particularly important for the iron ore tailings to turn waste into treasure for comprehensive utilization.In view of the comprehensive utilization effect evaluation characteristics of iron ore tailings,the paper established the effectiveness evaluation index system of comprehensive utilization of iron ore tailing,and put forward a kind of element extension model to evaluate comprehensive utilization effect of iron ore tailings.Finally,apractical example was used to demonstrate the effectiveness and practicability of the proposed method.The results show that the method is practical in the comprehensive utilization effect evaluation of iron ore tailing. | Abstract In order to characterize the most superadditive behavior of a risk measure, the notion of extreme-aggregation risk measures was introduced in the literature. In this short note, explicit forms of the extreme-aggregation measures induced by rank-dependent expected utility (RDEU) functionals and by RDEU-based shortfall risk measures are derived. The main results generalize those known in the literature. | eng_Latn | 28,083 |
Distribution and pollution evaluation of heavy metals in mine soils of Chang-Zhu-Tan city region | The concentration of Cd,Pb,Cu,Mn,Zn in mine soils of Chang-Zhu-Tan city region were measured,and their pollution state was evulated by using the single-factor polluted index and N.L.Nemerow integrated polluted index.The results indicated that the concentration of N,P,K was not arrived the normal level in which plants would develop.Compared with the mean contents of these five heavy metals in soils in Hunan province,the Pb,Cd,Mn,Cu,Zn contents were obviously higher in four studied mines.The integrated polluted index of these five heavy metals were more than 3,the highest index was 931.2,the lowest index was 7.8.Cd heavy metal was mostly polluted in all soils. | The inhabit situation of Xiasong village of Chayashan town changed enormously after the liberation:House structure become more and more rational progressively,building design becomes more and more pluralism,the living space improves by a large margin,Construction material regenerate newer in great degree.The distance.of the family equipment and family facility is dwindling progres-sively with that of urbanite,courtyards of peasant family generally become more and more perfect.The changes of the inhabit situation of Xiasong village of Chayashan town refract the course that the peasant are towards the rich progressively after the liberation. | eng_Latn | 28,084 |
Isolation and characterization of piperine from the fruits of black pepper (Piper nigrum) | Black pepper (Piper nigrum) is a spice vine crop which is used as a food preservative and as an essential component in traditional medicines. The aim of this study was to extract, isolate and characterize the structure of piperine. The fruits of black pepper were extracted in ethanol and compounds present identified by TLC under iodine vapour. A compound (A2) having Rf value 0.54 was isolated by column chromatography which may be responsible for the pungency of black pepper. After recrystallization of the isolate with benzene and chloroform mixture (7:1) gave pale yellow crystals of m.p. 128~129o C (reported 130o C). The IR, 1 H NMR and mass spectra of the pure crystalline compound (A2) were recorded. The mass spectra of the compound (A2) showed molecular ion peak M+· at 284.5 which was similar to that of piperine (mol. wt. 285). | This article discussed the distribution of major and trace elements of peat in Yuanchi,Changbai Mountain.Four profiles were collected with Wardenaar peat sampler produced in Netherlands.Each sample was cut into 1～2 cm at the present.As far as the special physical conditions in Yuanchi are concerned,the content of major and trace elements(Na、K、Mg、Ca、 Al、Ti、Fe、Mn、Zn、Pb、Cu)were determined among different peat bogs.The elements distribution with depth in each peat profile was fully analyzed.Also we have analyzed the enrichment of different elements in peat profiles.Through the calculated M/Ti(M refers to Na、K、Mg、Ca、 Al、Ti、Fe、Mn、Zn、Pb、Cu) ratio,compared with ratio of M/Ti collected from literature,we concluded the differences among different peat bogs.The increasing content of Mn、Zn and Pb from bottom to top in peat profiles proves the increasing pollution of them in present environment,which has profound implications for environment. | eng_Latn | 28,085 |
Ex-situ remediation of a metal-contaminated superfund soil using selective extractants | The Superfund Amendments and Reauthorization Act requires the use of remedial technologies that permanently and significantly reduce the volume, toxicity, or mobility of contaminated materials at affected sites. Extractive processes can accomplish the requirements of the Superfund Amendments and Reauthorization Act. Ethylenediaminetetraacetic acid (EDTA), N-2(acetamido)iminodiacetic acid (ADA), pyridine-2,6-dicarboxylic acid (PDA), and hydrochloric acid (HCl) were evaluated over a range of concentrations and reaction times in batch studies for their ability to remove lead (Pb) and cadmium (Cd) from a Superfund soil (Pbtotal= 65,200 mg/kg, Cdtotal= 52 mg/kg). Lead extraction was limited by a slow overall reaction. The order of Pb removal by extractant was EDTA > ADA > PDA > HCL. The soil was subjected to three repeated 1 h extractions in which a maximum of 86, 84, 70, and 54% of the total soil Pb was removed with EDTA, ADA, PDA, and HCl, respectively. The soil was not treated to below the Pb regulatory lim... | With the construction of the power system in Shanxi Province,the environment of the whole district is turning for the worse.In some parts it even leads to soil erosion.According to the research on the impact of the project construction for the characteristic of soil erosion in Ruiguang heat-engine plant,Shanxi,forward exhaustive investigating and analyzing,the author divided the projects into four parts: industrial area,linear facilities,coal ash yard and temporary facilities.Then it do the typical design of engineering measure for every part, in order to avoid soil erosion from the projects construction effectively and supply reference for the same kind projects in Shanxi Province. | eng_Latn | 28,086 |
X-ray photoelectron spectroscopic study of the surface composition of sediment or soil models | Abstract X-ray photoelectron spectroscopy was applied to analyze the surface composition of sodium dihydrogenphosphate/ferric oxide systems and montmorillonite which were chosen as model sediment (soil) systems. Striking differences in the photoelectron emission intensities for certain elements were observed for samples of differing preparations and where the bulk composition of elements were retained. Adsorbed phosphate ion was persistent on ferric oxide surface against repeated leaching by water where sodium ion was lost completely from the surface. | Question about classification of ground water quality was studied by using Self-organizing Feature Map(SOM) method,taking Yujiagou area polluted by leachate of abandoned open-pit coal mine of Xinqiu in Fuxin as example.The water quality of 17 wells in the area polluted were classified in different degrees with different train epochs by using correlation functions in MATLAB and area polluted was determined.It is indicated by studied results that main party of grand water in Yujiagou area has been polluted and can not be drunk,and the results of classification is identical comparing with comprehensive index method,fuzzy comprehensive appraisal and grey associated analysis etc.,and application of SOM in classification of ground water quality is feasible. | eng_Latn | 28,087 |
Formation and properties of the Zr75−xAlxNi10Cu10Ti5 bulk metallic glasses | Abstract Zr-based bulk metallic glasses (BMGs) exhibit interesting mechanical properties since they combine high fracture stress, elastic strain (up to 2%), significant fracture toughness and good corrosion resistance. Quaternary systems with general composition Zr–Ni–Cu–Ti show wide composition ranges in which BMG can be obtained. The addition of the another element to the quaternary alloys often increases the glass forming ability (GFA). The aim of this work was to study the influence of aluminium content on the GFA and on the mechanical properties of the Zr–Ni–Cu–Ti alloys. Multicomponent Zr 75− x Al x Ni 10 Cu 10 Ti 5 ( x = 15, 20 at%) alloys were produced by melt spinning method obtaining ribbons, and by casting technique into a copper mould, manufacturing rod shape samples with maximum diameter of 2 mm. Supercooled liquid region depends on chemical composition and exceeds 45 °C. Vickers microhardness of studied alloys is comparable to the highest ones for other Zr-based BMG. | The characteristics of spatial distribution of heavy metals in the surface sediments of Lianyungang nearshore area in Jiangsu Province have been analyzed.28 surface sediments sample were collected.It was found that the main pollutant in each region was Cu,the sequence was As, Cd,Pb,and the pollution of Hg is lower relatively.The main influence of pollutant concentration distribution was caused by Linhong River,Alkali Factory's outlet and the West Dam Program.Compared with the Program in 1985,the pollution of heavy metals such as Pb and Cd,was slighter,while the pollution of Cu and As was more serious.Among these regions,the quality of sediments in the Alkali Factory was poorest,indicating that the pollution was getting from bad to worse. | eng_Latn | 28,088 |
Study on the Spatial Distribution of Heavy Metals in Sediments of Lianyungang Nearshore Area | The characteristics of spatial distribution of heavy metals in the surface sediments of Lianyungang nearshore area in Jiangsu Province have been analyzed.28 surface sediments sample were collected.It was found that the main pollutant in each region was Cu,the sequence was As, Cd,Pb,and the pollution of Hg is lower relatively.The main influence of pollutant concentration distribution was caused by Linhong River,Alkali Factory's outlet and the West Dam Program.Compared with the Program in 1985,the pollution of heavy metals such as Pb and Cd,was slighter,while the pollution of Cu and As was more serious.Among these regions,the quality of sediments in the Alkali Factory was poorest,indicating that the pollution was getting from bad to worse. | 1. ::: ::: The existance of continuous transition between structures of typeα-ThSi2 andα-GdSi2 in the homogeneity region for lanthanum disilicide is confirmed and was detected by the x-ray structural method. ::: ::: ::: ::: ::: 2. ::: ::: The decrease in statistical weight of the sp3 hybridization of Si electrons causes a rhombic distortion of the structure. ::: ::: ::: ::: ::: 3. ::: ::: As the defficiency of Si atoms increases in the lanthanum disilicides, there is an increase in the specific electroresistance and Hall coefficient due to filling of the 3p silicon band. | eng_Latn | 28,089 |
Preparation and optical absorption of MnxZn1−xS | In this paper results on crystal growth of MnxZn1−xS with 0<x≤0.50 are reported. Monocrystals were grown by chemical transport. The biggest crystals obtained were of 0.5 cm3. Existence of the bands at the energy of 3.21; 2.93; 2.68; 2.52 and 2.38 eV was observed in the absorption measurement. The position of the bands does not vary with the composition x and temperature, but their intensity increases as x increases. Some discussion on these results are presented. | In this paper,soil sample of Jinkeng region in Suichuan was taken as research object,the geochemical data of metal elements which include Au,Ag,As,Sb,Cu,Pb,Zn,W,Bi and Sn were analyzed.The normal distribution data was formed by using probabilistic statistical analysis to exclude special high and low value.The abnormal range of 10 metal elements was delineated by using spatial analysis of MAPGIS,and the factors which influence abnormal range were reduced by using principal component analysis.Finally the distribution characteristics of 10 metal elements in soil were mapped.The results show that the geochemical differences of Au,Ag,Cu,Pb,Zn take on intensive distribution,and it will provide powerful support for further investigation. | eng_Latn | 28,090 |
Evidence for the identity of murine gamma interferon and macrophage activating factor. | Macrophages activating factor (MAF) in mouse lymphokine preparations was quantitated using a tumor cell cytotoxicity assay. MAF activity was compared with gamma interferon (IFN-gamma) activity, and the lymphokine mixture subjected to a variety of protein fractionation procedures. No significant difference in the ratio of MAF activity to IFN activity was observed following any of the fractionation steps, even after MAF had been purified to a specific activity of 1 X 10(6) u/mg protein. Gel permeation using high pressure liquid chromatography showed a coincident peak of MAF and IFN activity at approximately 55 kD. Both activities were reduced at similar rates following heating at 56 degrees C or incubation at 4 degrees C in pH 2 buffer. Finally, induction of lymphokines using different inducers (mitogens or antigens) or cell populations always resulted in similar ratios of MAF activity to IFN activity. These results support the hypothesis that MAF and IFN-gamma are identical proteins. | The International Centre for Research in Agroforestry (ICRAF) is a member of the Consultative Group on International Agricultural Research (CGIAR) system and has recently established a Multipurpose Tree Germplasm Resource Unit (MPT-GRU) in Nairobi, Kenya. The first major activity of the MPT-GRU was to undertake a regional germplasm collection ofSesbania in 5 countries in southern Africa in a collaborative mode with National Agricultural Research Services (NARS). The collections took place in Botswana, Malawi, Namibia, Zambia and Zimbabwe. | eng_Latn | 28,091 |
Magnetism of Fe clusters in YBa2(Cu1−xFex)3Oy | Abstract Reducing atmosphere preparations (RP) of title compounds with subsequent reoxigenations produce more extended Fe clustering on Cu(1) sites and an increase of the relative occupations on Cu(2), by comparison with conventional oxygenating atmosphere preparations (OP). Within a microscopic model for RP we discuss their increased magnetic and superconducting transition temperatures, local Fe magnetic moments and valence states. Data from Mossbauer spectroscopy indicate a distinction of local coordinations between bulk and surface of clusters and a likely Fe clustering also on Cu(2). Superconducting pair breaking per random Fe on Cu(2) is shown to be one order of magnitude stronger than for Zn. Fe clustering has the potential to increase the flux pinning, and influence the mode of magnetic order. | The characteristics of spatial distribution of heavy metals in the surface sediments of Lianyungang nearshore area in Jiangsu Province have been analyzed.28 surface sediments sample were collected.It was found that the main pollutant in each region was Cu,the sequence was As, Cd,Pb,and the pollution of Hg is lower relatively.The main influence of pollutant concentration distribution was caused by Linhong River,Alkali Factory's outlet and the West Dam Program.Compared with the Program in 1985,the pollution of heavy metals such as Pb and Cd,was slighter,while the pollution of Cu and As was more serious.Among these regions,the quality of sediments in the Alkali Factory was poorest,indicating that the pollution was getting from bad to worse. | eng_Latn | 28,092 |
Effect of the annealing atmosphere on the Au site in Er + Au-implanted silica | Abstract The Au site in Er + Au-implanted silica has been investigated by X-ray absorption spectroscopy, after annealing at 600 °C in either neutral N 2 or reducing H 2 (4%):N 2 (95%) atmosphere. High-resolution X-ray fluorescence spectra collected near the Au L III -edge indicate the presence of oxidized Au atoms in the N 2 -annealed sample. Correspondingly, the EXAFS analysis shows a weak Au–O coordination only for the sample annealed in neutral atmosphere. For both cases, the EXAFS results evidence the presence of sub-nanometer metallic Au clusters: the cluster size, always below 1 nm, is smaller for the sample annealed in reducing atmosphere. The Au clusters embedded in the Er-doped layer promote a strong enhancement of the Er photoluminescence emission at 1.5 μm. | The characteristics of spatial distribution of heavy metals in the surface sediments of Lianyungang nearshore area in Jiangsu Province have been analyzed.28 surface sediments sample were collected.It was found that the main pollutant in each region was Cu,the sequence was As, Cd,Pb,and the pollution of Hg is lower relatively.The main influence of pollutant concentration distribution was caused by Linhong River,Alkali Factory's outlet and the West Dam Program.Compared with the Program in 1985,the pollution of heavy metals such as Pb and Cd,was slighter,while the pollution of Cu and As was more serious.Among these regions,the quality of sediments in the Alkali Factory was poorest,indicating that the pollution was getting from bad to worse. | eng_Latn | 28,093 |
Tritium dose criteria and radiological impact of a tritium plant | Radiation safetry criteria adopted in Russia (in the former USSR) distinguish five classes of tritium compounds. The lowest permissible tritium concentration in the air is set for insoluble tritium compounds (3.105 times lower than that for HT). Russia's criteria for tritiated radioactive waste are outlined. It is explained why the tritium weighting factor of two is used as a basis for the tritium dose criteria development in this country. The ecological situation nearby a large tritium processing plant is considered. Amounts of tritiated waste produced at the plant, sources of tritium effluents, tritium content in the air, water, snow, soil and vegetation as well as HTO sorption parameters of various food products are reported. On the basis of HTO near-surface concentrations in the air and public doses measured 3 km away from the plant stack, the tritium dose factor was calculated. | The survival of energy plants during the construction of the Three-Gorges Reservoir Project was investigated based on the specific geography and climate characteristics in this area.Some protective measures for energy plants were put forward in order to support government decision-making for development of biomass energy. | eng_Latn | 28,094 |
Preparation method of cadmium antimonide powder | The preparation method of cadmium telluride powder includes the following steps: firstly, mixing tellurium powder and cadmium powder according to chemical mixing ratio, grinding and stirring mixed material, placing the mixed material in the crucible under the condition of vacuum, heating to make the tellurium powder and cadmium powder produce chemical combination reaction to form cadmium telluride material, further grinding the obtained cadmium telluride material and mixing it further, and placing the cadmium telluride material in heating furnace to make annealing treatment so as to obtain the invented product. | Abstract Binding capacities and conditional stability constants for Cu and Cd in sewage sludges were determined. Two different sludges were investigated; a secondary sludge and an anaerobically digested sludge. Free metal 1on concentration were determined using differential pulse anodic stripping voltammetry (DPASV) and atomic absorption spectrometry following separation of bound and free species by dialysis. DPASV results are affected by complexes lability but the differences with dialysis measured values give information about metals availability. | eng_Latn | 28,095 |
BASIC CHARACTERISTICS AND PROGNOSIS OF PB-ZN DEPOSITS IN THE WESTERN HUBEI PROVINCE | Pb-Zn deposits in the western Hubei Province were mainly formed through sedimentation and hydrothermal deposition. Sedimentary type deposits usually formed during late Sinian to Cambrian period. Hydrothermal type deposits are mainly related to middle-late Yanshanian regional extension, and mineralization happened mainly in Qingfeng competent deformation zone, western Shennongjia faulted dome, northern Huangling faulted dome, secondary Xianfeng and Zoumaping anticline. Recent explorations show that there are very excellent geological conditions and prospecting potential in the studied region. | The paper describes the building process beauty country,assess environment of rural human settlement of Jubao bay after construction in the method of the Post-Occupancy Evaluation construction completion.Investigate that is related to users,in order to appraisal to environment of rural human settlement of Jubao bay of Jiaxing city.In finally,proved the result of country planning practice of Jubao bay in the aspect of uesrs. | yue_Hant | 28,096 |
A study on the degree of importance of families of the medicinal flora in Cenwanglaoshan Natural Reserve,Guangxi Province,China | This study was undertaken to determine the degree of importance of plant families in the medicinal flora of Cenwanglaoshan Natural Reserve,Guangxi Province,China.A regression residual analysis was carried out on the number of medicinal species and the total number of species in each family for 166 angiosperm families in the Natural Reserve.According to the residual values,the 166 families were categorized into 100 high use families and 66 low use families. | Through elaborating the protection status of the Nanxun old town,it shows basic thinking of the protection for old town.From aspects of architectures and environment,management system and protection mode and other aspects,it explores and discusses problems existing in the protection and redevelopment of the Nanxun old town,and puts forward reasonable suggestions,which has profound significance for building the cityscape with local characteristics. | eng_Latn | 28,097 |
Health and well-being of the homeless in South African cities and towns | Little is known about the health and well-being of people who live on the streets although their lifestyle involves health risks. This study used qualitative and quantitative methods to explore the health status and health service needs of homeless people in several South African cities and towns. It was found in some cases that their own or family members' ill-health had contributed to their homelessness. Illnesses associated with poor living conditions or lifestyles were more common in the homeless than in the general population in certain age and sex categories. Access to healthcare was generally good in urban centres and most respondents were satisfied, although some reported discriminatory treatment. The risk profile of the homeless shows that systematic health promotion is required and that some health service providers need to be made more aware of the health needs of the homeless. | The problem of sustainable development and the role of universities of resources, which is the scientific and educational base of the mining industry is discussed. Assessment of management effectiveness of national total capital leading mining countries in the OECD and BRICS is given. On the basis of the Hartwick-Solow criterion proposed investment areas of mineral rents in natural, produced and human capital. The main tasks of the universities resources for the sustainable development of countries with large reserves of mineral resources updated. DOI: 10.5901/mjss.2015.v6n2s4p157 | eng_Latn | 28,098 |
Planting Performance and High-yielding Cultivation Techniques of Hybrid Rice Combination II Yonhang 2 | Ⅱ Yonhang 2 was a new hybrid rice combination developed by Rice Research Institute, Fujian Academy of Agricultural Sciences. During the year of 2011-2012, Ⅱ Yonhang 2 was introduced and planted in Jianou county of Fujian province, which showed developed root system, tillering capacity better, extensive adaptability, good maturing phase, rice quality, high and stable yield and disease resistance. In this paper, we introduced planting performance and high-yielding cultivation techniques of Ⅱ Yonhang 2. | This paper briefly analyzed the reforming state and solid influence of the collectivity forest-property of Yong'an city,through investigating the changing of forest property right in abroad and hometown at the present.It will provide the practised reference for the reforming of the collectivity forest-right in Fujian's province. | eng_Latn | 28,099 |
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