Search is not available for this dataset
query
stringlengths 1
13.4k
| pos
stringlengths 1
61k
| neg
stringlengths 1
63.9k
| query_lang
stringclasses 147
values | __index_level_0__
int64 0
3.11M
|
|---|---|---|---|---|
Triple-resonance 1H,19F,13C solid-state CPMAS NMR was used to examine the miscibility of isotactic, syndiotactic, or atactic PMMA with poly(vinylidene fluoride) (I). From the fluorine-to-carbon cross-polarization expts., the av. distance between F and OCH3 carbons in intimately mixed I and PMMA was estd. Exptl. evidence for a specific interaction between I and PMMA segments was presented. The proton-to-fluorine cross-depolarization expts. yielded information on size and compn. of the mixed PMMA/I phase. The fraction of nonmixed PMMA was detd. for these blends, and this fraction was smaller for isotactic than for atactic and syndiotactic PMMA. Large differences in the amts. of isolated PMMA were obsd. between melt-mixed and copptd. blends. | Melt compounding was used to prepare polycarbonate (PC)–zirconia nanocomposites with different amounts of zirconia. The effect of the zirconia loading, in the range of 1–5 wt.%, on the structure, mechanical properties and thermal degradation kinetics was investigated. The zirconia nanoparticle aggregates were well dispersed in the PC matrix and induced the appearance of a local lamellar order in the polycarbonate as inferred by SAXS findings. This order could be a consequence of the intermolecular interactions between zirconia and the polymer, in particular with the quaternary carbon bonded to the methyl groups and the methyl carbon as inferred from the NMR results. The presence of zirconia caused a decrease in the storage and loss moduli below the glass transition temperature. However, the highest amount of zirconia increased the modulus. The presence of zirconia in PC slightly increased the thermal stability, except for the highest zirconia content which showed a decrease. The activation energies of thermal degradation for the nanocomposites were significantly lower than that for pure PC at all degrees of conversion. | Two diblock copolymers of poly(methyl methacrylate)-block-poly(styrene) with chlorine as terminal group (PMMA-b-PS-Cl) were synthesized via two-step atom transfer radical polymerization. The struct... | eng_Latn | 21,600 |
The by-products of dicumyl peroxide (DCP) from the crosslinking process such as acetophenone, cumyl alcohol and ?-methylstyrene are said to be the sources of space charge formation in XLPE cable due to deep traps in the chemicals. However, by using space-charge experimental approach, it appeared that these chemicals show a different trapping nature. This paper is intended to present this approach. Additive-free low density polyethylene (LDPE) was used as base material so that each chemical can be tested individually. Space charge measurement was done using the pulse electroacoustic (PEA) method. All results were compared to the clean LDPE to identify the contribution of the chemicals to the trapping characteristic. The data collected supported that although the chemicals introduce charge in the insulator, the charge decay is extremely fast especially in the presence of ?-methylstyrene. It is believed that the chemicals modify the trapping characteristic of LDPE so that more shallow traps are formed in the insulator. | LDPE films were soaked into crosslinking byproducts which are acetophenone, a-methylstyrene and cumyl alcohol. The samples were used to perform the breakdown test. The ac breakdown measurements were conducted at a ramp rate of 50V/s at room temperature. Weibull plot is used to analyze the ac breakdown result. Comparing the soaked and un-soaked samples, it does show a small change in the characteristic breakdown strength as the LDPE film were soaked into the sample depending on the byproducts. It suggests that the breakdown strength is modified by adding the byproducts in the LDPE film. However, as the range of breakdown strength of all samples are to be compared, these values fall in the same region which indicate no significant difference can be seen in the samples. AC Pulsed Electroacoustic (PEA) technique was used to measure space charge in the samples. The result obtained from this test is used to explain the breakdown phenomena in the crosslinking byproduct soaked LDPE and space charge characteristics. | Convergence of a space decomposition method is proved for a class of convex programming problems. A space decomposition refers to a method that decomposes a space into a sum of subspaces, which could be a domain decomposition or a multilevel method when applied to partial differential equations. Two algorithms are proposed. Both can be used for linear as well as nonlinear elliptic problems, and they reduce to the standard additive and multiplicative Schwarz methods for linear elliptic problems. | eng_Latn | 21,601 |
The results of a detailed characterization study of a novel UV-activated colorimetric oxygen indicator are described. The indicator uses nanoparticles of titania to photosensitize the reduction of methylene blue by triethanolamine in a polymer encapsulation medium, using UVA light. Upon UV irradiation, the indicator bleaches and remains in this colorless state in the dark, unless and until it is exposed to oxygen, whereupon its original color is restored. The indicator is reusable and irreversible. The rate of color recovery is proportional to the level of oxygen present. A layer of PET (poly(ethylene terephthalate)), of thickness b, placed on top of the indicator film slows down its response, and the 90% recovery time is proportional to b. | Ultraviolet-visible (UV-vis) and fluorescence spectroscopy have been used to characterize the polyelectrolyte complexes (PECs) formed when potassium indigo tetrasulfonate (ITS) interacts with poly diallydimethylammonium chloride (PDADMAC) through columbic attraction in the presence of the reducing agent sodium bisulfite, NaHSO3. The PDADMAC facilitates both the reduction of the ITS and the stabilization of the reduced state of the ITS in an atmospheric oxygen environment. Dilutions of the dye solution show that the PEC is stable to dilutions of at least 1 to 1000. UV-vis studies indicate that the reduced ITS (ITSred) forms what is likely a J-aggregate in the presence of PDADMAC with an absorbance band red shifted from the normal absorbance band of reduced ITS by roughly 130 nm, 390 nm to 520 nm. Excitation of the PEC solution at either 390 nm or 520 nm produces an emission spectrum of the aggregated complex with an emission maximum near 534 nm. Monomer emission at 480 nm of ITSred represents only 3.0 ± 0.5% of the emission signal of the aggregated complex. Kinetic studies using fluorescence spectroscopy over a temperature range of 30 to 70 °C and dilutions of dye solutions ranging from 1:10 to 1:1000 yield data for the oxidation of ITSred that is best fit by a first order rate constant. Kinetic data displays two distinctive regimes, a short time rate and a long time rate. These two distinct kinetic regimes are likely due to the reduced ITS interacting with an outer PEC environment and an inner PEC environment. First order rate constants could be used to estimate Δ‡H and Δ‡S of the oxidation reaction. Fluorescence data was used to calculate the partitioning of reduced ITS molecules between the outer and inner PEC environments. Partitioning from the inner to outer PEC environment was found to be entropically driven. Addition of NaCl to the diluted dye solutions could alter the kinetics of the oxidation but the significance of the effect depended on the initial dye solution preparation. | Methylene Blue (MB) and Xanthene (XE) dyes sensitized polyvinyl alcohol have been employed for application of correlation peak detection. Bleaching of the MB and XE sensitized films has been studied in detail. The effect of various amines on the bleaching efficiency has been presented. The dark reversibility of these systems has also been evaluated. | eng_Latn | 21,602 |
Unlike conventional emulsion polymerization, monomer droplet nucleation becomes dominant in miniemulsion polymerization, offering the miniemulsion polymerization a great advantage over conventional emulsion polymerization when incorporating alkoxysilane monomer, which can easily undergo premature hydrolysis and condensation reactions, into polymer latex. The extensive premature hydrolysis and condensation can lead to the issue of the colloidal instability. In this article, the influence of monomer types on the colloidal stability in the miniemulsion co-(or ter-)polymerization was investigated when incorporating alkoxysilane monomer into styrene or acrylate latex. In the cases of butyl acrylate (BA)/γ-methacryoxypropytrimethoxysilane (MPMS), BA/methyl methyacrlate (MMA)/MPMS, and BA/styrene (St)/MPMS miniemulsion polymerization, nearly no coagulum was observed. The obtained latex had a long shelf life. However, the coagulum was formed in the late stage of MMA/MPMS and St/MPMS miniemulsion copolymerization. The shelf life of the corresponding latex was short. The selection of the main monomer, which can fast consume alkoxysilane comonomer, was critical to obtain the stable latex. In this way, the alkoxysilane groups were completely buried in particles thus the coagulation caused by condensation reactions derived from the alkoxysilane hydrolysis among particles was suppressed. | With the assistance of ultrasound, octamethylcyclotetrasiloxane (D4) and slight silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560) were sufficiently mixed with silica sol, and the in situ ring-opening polymerization of D4 on the surface of silica nanoparticles, catalyzed by dodecylbenzene sulfonic acid (DBSA), was enhanced as well. Thus, polydimethylsiloxane (PDMS)-modified silica (PDMS-ormosil) mixture was obtained. A slight addition of silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560) could significantly enhance the modified efficiency. The PDMS-ormosil mixtures were directly dispersed in the mixed monomer methyl methacrylate and butyl methacrylate. Then, miniemulsion polymerizations of acrylate monomers containing PDMS-ormosils were carried out, with free PDMS as hydrophobe and neutralized DBSA as emulsifier, both preexisted in the PDMS-ormosil mixture. Thus, the troubles of separation, purification, and redispersion in the traditional techniques can be omitted. Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscope, scanning electron microscope, and water contact angle tests were utilized to demonstrate that nanocomposite particles with a core–shell structure were synthesized; when the silica content was 3 wt% of the monomers, the average particle size was 97 nm, and the generated PDMS improved the hydrophobicity of the nanocomposite latex. | A model-based framework for advanced optimal operation of copolymerization processes was developed and tested experimentally in conjunction with a distributed control system (DCS) suitable for industrial application. A test case of emulsion copolymerization of styrene (Sty) and methyl-methacrylate (MMA) was investigated for predicting and optimizing key product properties including molecular weight distribution (MWD), particle size distribution (PSD), copolymer composition and conversion. The model equations include diffusion-controlled kinetics at high monomer conversions, where transition from a ‘zero-one’ to a ‘pseudo-bulk’ regime occurs. The reactor mass and energy balances describe the system transients for batch and semi-batch operations. Population balance equations, describe the particle evolution and comprise sets of integro-partial differential and nonlinear algebraic equations. The models were solved using an efficient numerical scheme suitable for on-line monitoring and control. The model predictions were found to be in good agreement with experimental results for measurements carried out with variable monomer feed rates, variable temperature and variable composition of styrene-MMA, from 25/75 to 75/25 proportions. The manipulation of these variables was found to affect the PSD significantly. The experimental results confirmed the accuracy of our optimization scheme for the desired conversion, MWD and PSD. | eng_Latn | 21,603 |
Differential scanning calorimetry (DSC) has been used to study samples taken from three paintings during treatment in the Conservation Department of the Tate Gallery. The paintings include two from the 16th century: (1) “Queen Elizabeth 1” by Nicholas Hilliard (National Portrait Gallery, London NPG 190), (2) “An Allegory of Life” (unattributed ca. 1570 British School To 5729) and (3) 19th century, Turner's ‘The Opening of the Walhalla, 1842’ (Tate Gallery N00533). Knowledge of the type of paint media used is of interest both to the conservator who needs to select the appropriate materials for cleaning the painting and to the art historian for documentation of artists' techniques. In the case of the Hilliard painting it was found that a mixed oil egg medium had been used. With regard to the unattributed 16th century British painting it was found that an oil-based medium had been used. The ground layer contained, as expected, a natural glue. Samples from the Turner painting showed that different regions of the painting had been executed with different materials; the region of the sky was painted predominantly with a drying oil, the lower regions of the painting contained mixtures of oil and resin and in some cases the samples were further complicated by the presence of proteinaceous material and wax. The recorded accompanying weight change gave information on the pigment volume concentration of the samples. In each case measurements were made of both the temperature and the heat evolved during the exothermic reactions. Thermomicroscopy and Fourier transform infrared spectroscopy (FTIR) confirmed the presence of complex mixtures, particularly in the case of the Turner samples. | Background ::: The chemical composition of the crude waxes extracted from three different seed oils (sunflower, canola, and cottonseed) was studied using chromatographic techniques. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 21,604 |
The advantageous application of a falling-film microreactor for a photochemical gas/liquid reaction was demonstrated by the selective photochlorination of toluene-2,4-diisocyanate (TDI) In the microstructured reactor the selectivity to the side-chain chlorinated product 1 -chloromethyl-2,4-diisocyanatobenzene (1CI-TDI) achieved a value of 80% at 55% TDI conversion, whereas the side product toluene-5-chloro-2,4-diisocyanate (5CI-TDI) was formed with only 5% selectivity. The yield of 1CI-TDI was enhanced by increasing the residence time from 24% after 5 s to 54% after 14 s. At the same time the formation of consecutive products increased and the selectivity to 1CI-TDI decreased to 67% after 14 s residence time. The influence of the reactor material was shown. In presence of a Lewis acid such as FeCl 3 , formed by chlorination using a reaction plate made of iron, consecutive products were formed and the selectivity to 1CI-TDI was lowered. The microstructured reactor led to remarkably higher selectivities than the conventional batch reactor, where the selectivity to 1CI-TDI was only 45% at 65% TDI conversion and the side product 5CI-TDI was formed with 50% selectivity. The space-time yield of 1CI-TDI achieved in the microstructured reactor (400 mol I - 1 h - 1 ) clearly exceeded the performance of the batch reactor (space-time yield 1.3 mol I - 1 h - 1 ). Based on the microreactor data, a kinetic model for the TDI chlorination including by-product formation was suggested and used to predict product selectivity at full TDI conversion. | Microstructured reactors with their benefits especially concerning enhanced mass and heat transfer represent a means for process intensification. A broadly used microstructured lab tool in the area of gas/liquid contacting is the Falling Film Microreactor (FFMR) developed by IMM in which liquid films of a few tens of micrometer thickness and interfacial areas of up to 20,000 m 2 /m 3 combined with an effective heat exchange can be obtained. Now the concept of the Falling Film Microreactor has been developed further with regard to increasing throughput in order to reach pilot production level and as a basis for future production scale throughput. Therefore, two different prototypes with a more than tenfold larger structured surface area have been developed and realized. The feasibility of a corresponding increase of throughput has been demonstrated for the oxidation of an organic compound using oxygen which is closely linked to an industrial relevant reaction and additionally by the absorption of CO2 in an aqueous sodium hydroxide solution. Naturally, process optimisation itself also contributes to the efforts to increase throughput. Therefore, in parallel the oxidation reaction has been optimised both varying process parameters (temperature, flow rates, pressure) and reactor parameters (microchannel width and depth) in the original, standard Falling Film Microreactor. Conducting experiments at 10 bar instead of ambient pressure and using a reaction plate with 1200 µm x 400 µm channels instead of 600 µm x 200 µm channels lead to an increase in conversion. These investigations also encourage repetition, setter and exploring more challenging process conditions and thereby following the concept of “novel chemistry”. | Background: Toluene diisocyanate (TDI) can cause contact allergy and occupational asthma, but the mechanism underlying sensitization to this chemical compound remains controversal. Also the correlation of mast cell with contact hypersensitivity (CHS) and the role of mast cell in the TDI-induced CHS is unknown. This issue was investigated by administrating TDI on the skin of genetically mast cell-deficient WBB6F1/J-Kit W / Kit W-v (W/W V ) and congenic normal WBB6F1/J-Kit+/+ (+/+) mice. Methods: To development of animal model of TDI-induced CHS and to investigate the correlation of mast cell with CHS and the role of mast cell in the TDI-induced CHS, W/W V and +/+ mice were sensitized with TDI on the back skin at day 1 and day 8, and then challenged with 1% TDI on the ear at day 15. At 1, 2, 4, 8, and 24 hours after 1% TDI challenge, the ear thicknesses were measured. It was investigated the histologic changes of dermis in the ear of W/W V and +/+ mice at 24 hours after 1% TDI challenge. Results: TDI induced a significant ear swelling response in W/W V and +/+ mice. TDI induced the significant infiltrations of polymorphonuclear leukocytes and eosinophils in W/W V and +/+ mice, but not of mast cells in normal mice. And TDI increased a characteristic extent of mast cell degranulation in normal mice. There were no significant differences in the ear swelling and the infiltrations of polymorphonuclear leukocytes and eosinophils of normal versus W/W V mice, either at baseline or after TDI-induced CHS. Conclusion: From the above results, TDI can be used as a murine CHS model, and the mast cells may not be essential in TDI-induced CHS. (Immune Network 2002;2(3):158-165) | eng_Latn | 21,605 |
Synthesis and curing study of a new phenolphthalein-formaldehyde resin | Abstract The preparation of a new methylolic resin derived from condensation of phenolphthalein and formaldehyde is described. The resin was characterised by spectroscopic, elemental analysis and moisture evolution analysis (MEA) techniques. The thermosetting (curing) characteristics of the resin were investigated by MEA and differential scanning calorimetry. Several thermosetting parameters were determined, i.e. rate of setting, degree of setting and the activation energy of the setting reactions, and the determined values for the latter parameter were found to be 58.2 and 18.29 kJ mol −1 which were related to the dehydration and dehydroformylation reactions respectively. The degree of setting varies linearly with temperature. | This paper presents an inferential property prediction scheme for a high pressure polyethylene autoclave reactor. The development of a dynamic model of the process is described. It was derived from a consideration of the reaction mechanism and uses reaction temperatures, pressure and gas composition to predict the degree of polymerisation of the polymer. The values of certain key parameters in the model were derived from steady state data from the ICI Alkathenc plant at Botany Site. The model was shown to predict the degree of polymerisation during grade transition with an appropriate accuracy although it benefited from an on-line adaption scheme. | eng_Latn | 21,606 |
Determination of ferulic acid in yangyin zhenjing tablet by RP-HPLC | OBJECTIVE To establish a method for determination the content of ferulic acid in Yangyin Zhenjing tablet by HPLC. METHOD Discovery C 18 was used as a stationary phase, acetontrile 0.5% acetic acid solution (20∶80) was used as the mobile phase. The UV VIS dector was set at 335nm.RESULTS The assay was linear in the range of 0.01444～0.1083mg/mL( r =0.9999). The average recovery of ferulic acid was 97.13%( RSD =2.0%).CONCLUSION The method is simple and accurate with a good reproducibility, which can be used as quantitative method for this preparation. | The invention discloses a structural formula of fluorenyl benzoxazine and a preparation method thereof. In the invention, reaction raw materials comprise fluorenyl phenol, non-fluorenyl unitary primary amine or non-fluorenyl binary primary amine or fluorenyl unitary primary amine or fluorenyl binary primary amine and methanal; or the reaction raw materials comprise non-fluorenyl phenol, fluorenyl unitary primary amine or fluorenyl binary primary amine and methanal; the fluorenyl benzoxazine is prepared and synthesized by adopting a solvent method, and the reaction temperature is 60-150 DEG C; then the reaction system is washed by adopting distilled water or absolute ethyl alcohol; and water or alcohol is removed in vacuum. The fluorenyl benzoxazine has good heat resistance and dielectrical property and can be applied to the fields of reinforcing materials, fillers, composite materials, and the like of adhesives, coatings, laminated sheets, printed circuit boards and semiconductor packaging materials. | eng_Latn | 21,607 |
Peritoneal mesothelioma: description of a case and review of literature. | It is universally recognized by the scientific community that asbestos, widely used in the past in many industrial sectors, is responsible for the onset of certain diseases of pleural and peritoneal serous membranes; in particular, Peritoneal Mesothelioma (PM) is an exceptional case, extremely rare malignancy of the abdominal cavity. In this work we describe a 62 years-old man, formerly exposed to asbestos, complains of dyspepsia associated with pain, abdominal swelling and mild difficulty during inspiration. After intraoperative biopsy of three masses found in abdomen, malignant peritoneal mesothelioma was diagnosed. The patient subsequently was subjected to cycles of chemotherapy and multiple palliative paracentesis, the patient died after about 12 months from diagnosis. | Abstract The impinging jet with a parabolic inlet profile was modeled numerically and the results were compared to an existing series solution. The results at nozzle heights of 0.5 radii and above agreed within 1% of the series solution, but discrepancies of several percent were obtained at nozzle heights below 0.375 radii where the series solution did not converge well. Numerical solutions that allowed for thermal gradients, details of an actual impinging jet reactor, and cadmium telluride deposition from organometallic precursors, were also obtained. The experimentally-derived mass-transfer-limited deposition profile and the model simulations agreed when the model's concentrations at the bubbler outlets were reduced by a factor of four from the saturation values. This correction was justified when an inventory of reactant revealed that the mixtures at the bubbler outlets were far from saturated. | eng_Latn | 21,608 |
A Brief Description of Contemporary Polymers | Polymer is a kind of rather special vocabulary in contempoary Chinese.They are quite active but paid little attention to.Based on the limited research of the predecessors the writer trys to do further inquiry into the concept,classification,and grammatical features of polymers,and trys to explore the law of internal morpheme's order from the tone. | Overview of physical mechanisms of photopolymers formations for laser and holographic applications. | eng_Latn | 21,609 |
The method of manufacturing a vapor deposition mask, a method and apparatus for producing a vapor deposition mask organic semiconductor element | The present invention is a vapor deposition mask, a method for producing a vapor deposition mask device and manufacturing method of the organic semiconductor element, an object is to provide a vapor deposition mask size may even meet the high definition and lightweight, this deposition mask can be precisely adjusted to the position of the vapor deposition mask manufacturing method of the device housing and a method for producing an organic semiconductor element can be manufactured of a high-definition organic semiconductor element. Laminate constituted a slit provided in the metal mask and the resin mask, the resin mask is in the metal mask surface, and the aspect is disposed with two or more openings corresponding to the pattern produced by vapor deposition of. | This article tested the amount of water vapor and oxygen permeability of plastics with different materials,reaches the conclusion that different materials are different for permeability,that the packing with double composite plastics by BOPP is better in water vapor permeability if at the same thickness,the one with one layer by PA is better in oxygen permeability,that the aluminium-plastic composite packing and aluminized packing′s permeability are much better than the composite packing without aluminium;aluminium-plastic composite packing is better than aluminized packing in water vapor permeability.And the test analyzed the basic factors resulting the difference,and gives a clue for the selection of material in respect of water vapor permeability in the field of food packing. | eng_Latn | 21,610 |
Modelling of Polymer Properties in Industrial Reactors | This paper presents an inferential property prediction scheme for a high pressure polyethylene autoclave reactor. The development of a dynamic model of the process is described. It was derived from a consideration of the reaction mechanism and uses reaction temperatures, pressure and gas composition to predict the degree of polymerisation of the polymer. The values of certain key parameters in the model were derived from steady state data from the ICI Alkathenc plant at Botany Site. The model was shown to predict the degree of polymerisation during grade transition with an appropriate accuracy although it benefited from an on-line adaption scheme. | This report presents the current problem in using chemical programming model to implement a service middleware that support flexible and adaptive service execution. | eng_Latn | 21,611 |
Fire retardant thermoplastic polyurethane resin composition for covering material of terecommunication cable | PURPOSE: A thermoplastic polyurethane resin composition is provided to maintain excellent flame retardancy by using a small amount of a flame retardant, to prevent efflorescence and bleeding phenomena, and to have a high scratch hardness. CONSTITUTION: A thermoplastic polyurethane resin composition comprises 50-74 wt% of a thermoplastic polyurethane, 1-10 wt% of a maleic anhydride-modified styrene-ethylene/butylene-styrene, 5-38 wt% of a melamine cyanurate, and 2-20 wt% of an organic phosphine acid salt. The molecular weight of the thermoplastic polyurethane is 20,000-700,000. In order to increase a compatibility with the thermoplastic polyurethane, 30-60 wt% of the styrene is used. | This paper describes the realization of Modbus RTU master/salve protocol based on SIMATIC S7-300 PLC point-to-point communication module.In a practical packaging control system,data is transmitted reliably and effectively.The scheme is worth promoting economic significance,for avoiding the expense of Siemens driver module of Modbus protocol. | eng_Latn | 21,612 |
Analysis of Fouling in Super Compressor and Intercooler During Production of Low Density Polyethylene | Fouling is widely found in super compressor and intercooler during the production of low densitypolyethylene.Melt index and density measurements show that polyethylene samples from super compressorand intercooler are 0.03 g /10 min,0.942 g /cm3,and 0.12 g /10 min,0.936 g /cm3,respectively,which indicatesthere are not entrainments from high pressure cycle gas system.FT-IR results of merchantable polyethylenepellets and fouling samples both show characteristic peak of tert-butyl at 1364.69cm-1,1375.24cm-1,and C=O of ester at 1721.42cm-1,1740cm-1.Characteristic peak of C-O is not found in the spectrum which meansoxygen does not work as initiator during the formation of the fouling.This article has fairly explained thesource of the free radical and formation of fouling in the super compressor and intercooler which is meaning-ful in the ways to solving this specific problem. | According to the defects of water-sealed tank of CO_2 recovery balloon of expansion line, the front protection device for CO_2 recovery balloon based on PLC is designed. | eng_Latn | 21,613 |
Way to put a plastic bottle and shrinkable label to the bottle | Three or body part having a polygonal cross-section with four sides and (2), the cross-section but similar to the cross section of the body portion (2) and the rotating surface shape or body part (2) Although not much emphasized plastic bottle with the neck of the bottle tapered portion which extends between the (7) and (5), the having. Its bottles to be covered with heat-shrinkable plastic films are particularly suitable. | We have investigated the depletion layer generated in DC poled soda-lime glasses using the LIPP technique. The results are interpreted taking advantage of the chemical surface analysis already carried out. | eng_Latn | 21,614 |
Grafting onto wool: 7. Determination of end groups of grafted polymer and homopolymer formed in methanol-benzoyl initiating system | Abstract A previous assessment of the end group incorporated in poly(methyl methacrylate) and polystyrene chains, based on the synthesis of the 2,4-dinitrophenyl (DNP) derivatives of hydroxyl and amino groups, has been extended. It has been found that in methanol-benzoyl peroxide initiating systems, hydroxyl, phenyl and benzoyloxy radicals initiate homopolymerization. The total number of end groups has been determined. From the results of the number of DNP-amino-acid end groups in the isolated polymer chain from the grafted fibres and from chemically modified fibres before and after grafting, it is postulated that two DNP-end groups are linked to the polymer chain, and one DNP—amino-acid is situated at each end of the polymer chain. No initiating mechanism visualized with respect to the homopolymerization is involved in the graft copolymerization. | A suite of programs is developed to analyze photomicrographs of the structure of nonwoven materials. Such programs are needed for deciphering the structural distinctions in multidimensional characteristics of the studied objects that contain information about their states. This allows their use for classification of objects describable by characteristics of a different physical nature without their pre-standardization. The explicit form of the proposed measures is given and the effectiveness of their use in algorithms for automatic classification is shown for clustering of the images of polypropylene spunbond nonwoven material. | eng_Latn | 21,615 |
NHC-Mediated Aggregation of P4: Isolation of a P12 Cluster | Just like transition metal complexes, N-heterocyclic carbenes (NHCs) promote the aggregation of white phosphorus (P4) as shown by the high yield synthesis of a P12 cluster capped by two NHCs. The nuclearity observed is equal to that of the largest phosphorus cluster prepared using transition metals, but the architecture of the P12 core is entirely novel. | Dynamic characteristic of a system have to be obtained so as to offer the reliable data for the system dynamic modification and dynamic optimum design. The system modal parameters identification can be changed into the global optimization problem in wavelet plane because the wavelet ridges can carry much information of system characteristic parameters. Firstly, the paper will introduce the so-called PSO (Particle Swarm Optimization) technique into the modal analysis and propose the PSO wavelet ridge extraction algorithm. Furthermore, the formulas identifying modal parameters from a wavelet ridge are derived and computation steps were given. The simulation experiments are implemented in order to evaluate precision of this method and the robustness of noise. Finally, the proposed method applies to the modal parameters identification of a watermelon to explore the effectiveness. The experiment results prove the method is precision and insensitive to noise. | eng_Latn | 21,616 |
Photochemically generated optical elements. I. A qualitative characterization of crosslinking gradients by low frequency microechography | Microechography was used to characterize crosslinking gradients in photopolymers, because this technique can produce acoustic images of amplitude variations of local mechanical properties. A frequency of 25 MHz was chosen due to the high absorption of the investigated material at high frequencies. Two sets of samples were studied. The former, which had been polymerized through a test mask and displayed sharp gradients, were used to check the sensitivity of the technique; the latter were insulated through a chromium apodizing filter with a radial density variation and allowed the resolution of the apparatus to be determined. Results obtained on the exposed sample surfaces and on cross sections showed that this technique is well suited to the study of crosslinking gradients in, photopolymers despite the resolution loss resulting from the use of low frequencies. The method is exemplified by the study of mask pattern transfer into a polymer. | Abstract Literature sources on metal-organic materials encapsulating versatile porphyrinoids and heme enzymes have been discussed in this review. General fundamentals and structural and chemical requisites of these architectures are discussed in introduction followed by historical perspectives of the initial composites. We have categorized the structural aspects of this class of compounds according to the host and guest skeletons as well as encapsulating strategies in a sequential manner. Heme mimetic, as well as some novel applications of the materials including oxidation, electron transfer, carbene transfer and bio-molecule sensing, are then discussed and compared with each other and their homogeneous analogues based on mechanistic similarities, wherever possible. | eng_Latn | 21,617 |
Failure of $\mathrm{F}$-purity and $\mathrm{F}$-regularity in certain rings of invariants | In this process a conductive first layer composed of finely divided metal and finely divided ceramic material in an organic carrier is applied to a surface of an unsintered ceramic body. The conductive layer forms terminations when the body, and the conductive layer are cofired to sinter and form a unitary, integral, monolithic structure. A second conductive metal layer may be applied to the first layer prior to cofiring to improve attachment capabilities of the component. Leads may be attached to the conductive terminations if desired. | Approximate solutions to the self‐consistent reference interaction‐site model (RISM) integral equation theory of polymer liquids are employed to study the conformational properties of flexible polymers as a function of density and chain length. The nonlinear nature of the expression describing the medium‐induced potential between two sites along the polymer chain necessitates the use of approximate methods to determine the intrachain pair‐correlation function consistent with the interchain packing. In the limiting case where the polymer segment hard‐core diameter approaches zero and the number of interaction sites comprising the chain goes to infinity, with the segment volume fraction held fixed, the intrachain pair correlation function is determined through a Feynman variational procedure for the effective free energy of a single chain in solution. The screening of the excluded volume interactions and the corresponding reduction of the polymer dimensions as a function of both polymer density and chain le... | eng_Latn | 21,618 |
Quantification of residual monomer in polylactide by gas chromatographic internal standard method | An analytical method has been developed to quantitatively determine the residual lactide monomer in polylactide (PLA) using an internal standard method of gas chromatography (GC). The experimental results showed that diphenyl ether (DPE) was an appropriate internal standard for quantitative analysis of residual lactide in PLA. PLA and DPE were dissolved in dichloromethane and precipitated in hexane. At the same time, the residual lactide in PLA and DPE as an internal standard were extracted to hexane from the polymer solution. The resulting solution could be directly injected into a GC system. Therefore, the residual lactide was determined quantitatively using an internal standard method of GC. This method is practical for measuring the residual lactide content in PLA. When the lactide content is 5.0%, the relative standard deviation (RSD) of the measurements is 1.7%, while RSD is 6.9% at the low level of 0.4%, which indicates that the method is sufficiently precise. | The way to improve inkjet paper quality by surface sizing with synthesized polymer and its addition to the solutions of cationic starch and modified PVA was introduced.The water resistance and ink density were examined.The results show that some amount of polymer addition to the starch solution could be helpful to inkjet paper quality,and the polymer get the better quality in inkjet paper in water resistance and ink density than the starch sizing. | eng_Latn | 21,619 |
Application of Doehlert Matrix Design in Optimizing Ultrasonic-assisted Enzymatic Extraction of Polysaccharides from Corbicula fluminea | Ultrasonic-assisted Enzymatic Extraction Technology was applied to extract Corbicula fluminea polysaccharides. Four independent variables were extraction temperature,ultrasound time,ratio of material to liquid and ultrasonic power. Doehlert Matrix Design and Response Surface Methodology were used to determine the optimum process parameters that could give highest extraction yield. The optimal polysaccharide yield of 42. 7% was obtained under extraction temperature 82℃,ultrasonic time 35min,ratio of material to liquid 37 mL / g and ultrasonic power 270W. | This paper presents derivation of the probability distribution for the area enclosed by a polymer loop in a gel and under different external fields using white noise analysis. In this context, the polymer loop is represented by Brownian paths and its immersion in a gel constraints it to occupy a constant area[1]. The external fields considered are electric field, and crossed electric-magnetic fields. | eng_Latn | 21,620 |
Numerical Simulation of the Curing Stage in Reaction Injection Molding Process of Polyurethane | An attempt was made to develop a mathematical model for the curing behavior of polyurethane during the reaction injection molding. Reasonable assumptions and simplifications were introduced in the model, and an explicit finite difference scheme with the mathematical software Matlab was used to obtain temperature and conversion distribution in the thickness direction for a plate-type mold. The temperature and conversion calculated from the simulation was consistent compared with the experimental data. The demolding time, i.e., the time needed to achieve a minimum conversion of 80%, was found about 17s. In addition, the effects of catalyst concentration, feed temperature and wall temperature on the maximum exothermic temperature and the conversion were also explored to optimize molding conditions of reaction injection molding of polyurethane. | AbstractThe effect of uric acid as a photoprotective agent for various solutions of FD&C Blue No. 2 was investivated. Due to the poor aqueous solubility of uric acid, solutions were made in glycerin, triethanolamine and N/5 NaOH. Uric acid in glycerin or triethanolamine was found to enhance the photostability of the dye solutions. The higher the concentration of uric acid in triethanolamine, the greater was the photoprotective action of uric acid. Increasing the amount of glycerin in solution resulted in acceleration of the rate of fading of the color presumably due to dielectric constant effect. The photoprotective action of uric acid was found to be influenced by the pH of the medium and its buffer species. | eng_Latn | 21,621 |
Inks including graft copolymer surface-modified pigments via azide chemistry | Pigment based inks are provided. The inks include a non-polar carrier fluid and a surface-functionalized pigment particle including a nitrogen-linked moiety to the surface of the pigment particle through a nitrogen link at one end of the nitrogen-linked moiety and a graft copolymer having two or three blocks attached at another end, the pigment particle suspended in the non-polar carrier fluid, the nitrogen-linked moiety further including an alkyl chain interposed between the nitrogen-linked moiety and the graft copolymer having the structure (I), where X is the nitrogen-linked moiety and Y is a copolymer, and the letter a is an integer between 0 and about 5,000, while the letter b is an integer of 2 or more. | One way to increase efficiency and reduce pollution in transport and energetic domain is designing fuel injectors with better atomization. In this work, experiments were performed on a prefilming airblast atomizer often used in gas turbine engines. For this purpose, a new injector was designed to visualize the prefilming zone and the primary atomization together. The flow configuration corresponds to an annular liquid film sheared by inner high velocity airflows. High speed Shadowgraphy was used to observe film and spray, liquid film frequency, wave velocity and wave deformation, primary breakup regime. Finally, a link between liquid film and the primary atomization are shown first qualitatively and after quantitatively. | eng_Latn | 21,622 |
Polyethylene Squeeze Bottles for Potassium Hydroxide Solutions | The formation of precipitates in glass bottles containing the usual 10% potassium hydroxide solution used for examination of skin scrapings, nails, etc. for fungus elements has long been a source of annoyance to dermatologists. The precipitate consists largely of silicates due to the attack of the glass by the strong alkali solution. Upon questioning a number of practicing dermatologists it was apparent that very few were aware of the fact that polyethylene squeeze bottles now in wide commercial and laboratory use are relatively inert to the action of alkalis and that such solutions will remain clear in these bottles much longer than in glass bottles. The accompanying photograph shows two types of squeeze bottles which are available for office use. Type A has an internal tube with a finely tapered outside point. It has the advantage of forming a very fine drop, so that there is little chance | Cables in use in oil refineries, petro-chemical industries or other chemical plants are often left subjected to various sorts of chemical agents, oils and solvents, and we have heretofore experienced many examples of deterioration of such cables. In order to avoid such chemical deterioration, PE-sheathed cables have been mainly in use in those plants. | eng_Latn | 21,623 |
Building materials for the polyolefin composition | Outdoor building products, for example, house siding, exterior materials, lower, or about useful polyolefin compositions for roofing. This composition, a) one or more ultraviolet absorbers, b) one or more hindered amine light stabilizer, and c) one or more additives selected from the group consisting of one or more antioxidants containing polyolefin substrate which has been incorporated. Advantageously, the polyolefin substrate, d) 1 or more coloring agents, e) 1 or more fillers, f) 1 or more flame retardants, and optionally g) 1 or more even antimicrobial compound It has been incorporated. The compositions exhibit specific performance levels by standard tests, for example, impact strength measured at in-lb according ASTM D4226 is a 35 greater than the linear thermal measured in in / in / ft accordance ASTM D696 expansion coefficient is less than 4.5 × 10 | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | eng_Latn | 21,624 |
Preparation and Characteristics of Mercaptobenzene Functionalized Graphite and Epoxy-Based Hybrid Membranes | Here we report the preparation and characterization of mercaptobenzene functionalized graphite and bisphenol A ethoxylate diacrylate epoxy-based hybrid membranes (BAEDA/Graphite-MB). A series of gold nanoparticle and mercaptobenzene functionalized graphite and epoxy membranes (BAEDA/Graphite-MB-AuNPs) were also prepared. First a free-standing carbon-based membrane material was prepared using nylon filtering membrane. Afterwards, the composite membrane of Epoxy and functionalized graphite was prepared. The permutation of macroscopic structure was the result of unique morphology and improved thermal conductivity in BAEDA/Graphite-MB-AuNPs membranes. The thermal conductivity of BAEDA/Graphite-MB-AuNPs membranes ranged between 2.1 and 5.7 W/mK. The membrane property such as water permeability was also measured using relevant set-up. Higher water permeability of BAEDA/Graphite-MB-AuNPs membranes was observed due to better nanofiller dispersion. | Excellent weather resistance, print density (color developing property), it is possible to provide an ink jet ink capable of forming a printed good productivity having the fixing performance (wear resistance), which can also provide good productivity, a pigment dispersion having excellent dispersibility for its object to provide a polymer for ink jet ink. Cyclohexyl methacrylate units and 10-99% by weight, by the ink-jet ink copolymer and a pigment dispersion for ink-jet ink containing a pigment for the ink-jet ink and copolymers comprising acrylic acid units 1-90% by weight of the objects this is achieved. | eng_Latn | 21,625 |
X-ray diffraction and optical studies of fractionalized regioregular poly(3-hexylthiophene) | We report results of structural and photoabsorption studies of regioregular polyhexylthiophene fractions of different backbone length. Polymer of longer chains have better planarity and higher degree of crystallinity. The vibrational structure in the optical spectrum is more clearly visible. Increase of conjugation length and decrease of the optical gap with increasing polymerization degree have been observed. Moreover, the evolution of the photoabsorption spectra as a function of external pressure is presented. The spectra red shift with increasing pressure. The largest shifts have been observed for sample of the longest chains. The results are interpreted in terms of the large interchain coupling induced by pressure. | Disclosed is a precursor composition comprising: a compound selected from a compound represented by the formula: Si(OR 1 ) 4 and a compound represented by the formula R a (Si)(OR 2 ) 4-a (in the formulas R 1 represents a monovalent organic group; R represents a hydrogen atom, a fluorine atom or a monovalent organic group; R 2 represents a monovalent organic group; and a is an integer ranging from 1 to 3, provided that R, R 1 and R 2 may be the same or different from one another) a thermally degradable organic compound; an element having a catalyst activity; urea; and the like. A porous thin film produced from the precursor composition is irradiated with ultraviolet ray, and then subjected to gas-phase reaction with a hydrophobic compound. A porous thin film thus prepared can be used for the manufacture of a semiconductor device. | eng_Latn | 21,626 |
NaRb3B6O9(OH)3(HCO3): A Borate-Bicarbonate Nonlinear Optical Material | A noncentrosymmetric mixed alkali metal borate–bicarbonate, NaRb3B6O9(OH)3(HCO3), was synthesized and characterized. The compound crystallizes in the monoclinic space group P21 (No. 4) with a = 8.988(3) A, b = 8.889(2) A, c = 10.068(4) A, and β = 114.6(4)°. The structure features a combination of chains of boron–oxygen [B6O9 (OH)3]3– groups and isolated HCO3– groups, with charge compensation provided by Rb+ and Na+ cations. It exhibits a second harmonic generation response of about 0.5 × KDP. The UV–vis–NIR absorption spectrum indicated a transparency of about 40% at 200 nm. The IR spectrum confirms the coordination environments of anionic groups, and thermogravimetric measurements indicate the material is thermally stable up to approximately 320 °C. Additionally, first-principles calculations were performed in order to gain insight into the role of boron–oxygen and HCO3– groups with respect to the band structure and NLO properties. | Aiming at the problems existing in conventional cotton fabric bleaching such as high temperature and strength loss,a peroxide bleaching activator was prepared,and the main effective component was nonanoyloxy benzenesulfonate sodium(NOBS).The optimal synthetic conditions were as follows: 4-phenolsulfonate sodium was dissolved in sodium hydroxide solution(mole ratio of 1∶1),and then tetrabutyl ammonium bromide 5% was added.The mole ratio of nonanoyl chloride to 4-phenolsulfonate sodium was 1.3∶1 reacting at 30 ℃ for 80 min.The resulting product,without being separated,could be used as the peroxide bleaching activator and applied directly to the scouring and bleaching of pure cotton knitgoods.This peroxide bleaching activator offers such benefits as lowering bleaching temperature(80 ℃),acceptable bleaching effect,and less strength loss and energy consumption. | eng_Latn | 21,627 |
Stability of Factor Structure on the Semantic Differential: Retest Data: | Previous research on the semantic differential technique has found evidence for variance in Osgood's original formulation of three dimensions of connotative meaning: namely, Evaluation, Potency, and Activity. Piotrowski (1983a) reported on the inconsistency in factor structure with the exception of the Evaluative dimension. The present investigation reports retest data based on Piotrowski's original sample, after a 6-month time span. Three concepts (Hurricane, My City, and Myself) were analyzed in a fifth grade population. The results indicated support for the stability and consistency of the Evaluation dimension only. There was moderate consistency in scales which comprised the Potency and Activity dimensions. Researchers were cautioned about utilizing scales found valid in previous investigations. | Production of aqueous dispersions of polymeric nanoparticles via heterogeneous radical polymerization in emulsion-type systems is of enormous commercial importance. The ability to reversibly destabilize such a latex is highly desirable, for example, to save transportation costs. Herein, a method for synthesis of photo-responsive polymer latexes that can be destabilized (leading to sedimentation) by only using UV irradiation (no addition of chemicals or change in the experimental conditions) and subsequently redispersed by stirring under visible light irradiation is described. The destabilization/redispersion mechanism relies on photoinduced trans-cis isomerization of the cationic diazene surfactant 2-(4-(4-butylphenyl)diazenylphenoxy)ethyltrimethylammonium bromide (C4AzoTAB) used in conjunction with the anionic surfactant sodium dodecyl sulfate. It is demonstrated that reversible destabilization can be achieved very rapidly (90 s residence time) employing continuous flow technology. | eng_Latn | 21,628 |
Casimir Effect and Interaction between Surface Plasmons | In this thesis we discuss the influence of surface plasmons on the Casimir effect between two plane parallel metallic mirrors at arbitrary distances. Using the plasma model to describe the optical response of the metal, we express the Casimir energy as a sum of contributions associated with evanescent surface plasmon modes and propagative cavity modes. In contrast to expectations, the plasmonic mode contribution is essential at all distances in order to ensure the correct result for the Casimir energy. One of the two plasmonic modes gives rise to a repulsive contribution, balancing the attractive contributions from propagating cavity modes, while both contributions taken separately are much larger than the actual value of the Casimir energy. This also suggests possibilities to tailor the sign of the Casimir force via surface plasmons. | Abstract The feasibility of using a silicone rubber membrane to separate mixtures of isopropyl alcohol and water, including the azeotropic composition, has been demonstrated and a quantitative measure of efficiency of separation has been developed. One of the problem areas in studying liquid permeation is the variability in the polymer membrane structure. Such factors as the presence of solvents and plasticizers, previous thermal history, previous solvent history, and the degree of crystallinity of the polymer behavior affect membrane behavior. However, as the polymers are better understood, these drawbacks for the researcher may be of advantage to those tailoring a polymer to a specific use. | eng_Latn | 21,629 |
Study on Chemical Structures of Tetrafluoroethylene-Perfluoro-Alkyl-Vinylether Copolymer by EB-Irradiation in the Molten State | Perfluorinated polymers such as tetrafluoroethylene-perfluoroalkylvinylether copolymer (PFA) with remarkable chemical durability and thermal stability have been applied for industry. However, PFA has been classified to be typical radiation-degradable polymer. In our previous work [1], it has been found that crosslinked PFA has been obtained by irradiation under oxygen-free atmosphere in its molten state. In this study, the change of thermo-physical properties and the chemical structures of crosslinked PFA were studied by DSC and F-NMR. PFA was irradiated by soft electron beam (soft-EB) under nitrogen atmosphere at 583K±3K. | The present invention includes a polyvinyl acetal having a softening temperature Tg of less than 74 ° C., and at least one cyclohexanedicarboxylic acid ester as a plasticizer, a sheet containing a plasticizer. The plasticizer-containing sheets showed slight exudation tendency of plasticizers, combined may be used for the manufacture of glass and the photovoltaic module. | eng_Latn | 21,630 |
A wall paper and method for making thereof | The invention wallpaper and relates to a method of manufacturing the same, PVC (polyvinyl chloride) 100 parts by weight of DOP (di-octyl-phthalate) 10 parts by weight of a stabilizer 4 parts by weight, admired 4 parts by weight of antimony, 10 parts by weight, per 4 parts by weight, and can reduce the manufacturing process by making the front sheet by blending the PVC pigment and improve the flame retardancy sikimyeo can prevent the discoloration, the functional material to the opposite printed on the surface of the front sheet by using the water-based ink, and formed of a polyethylene resin to prevent carcinogen release by coating with an aqueous precipitation process, and it is possible to reduce the use of water-based ink and the drying time when water-based precipitation treatment through a hot air drying. | This picture is a portrait of W. C. Blight. This print was made from the original glass plate negative, which is housed at Virginia Historical Society. | eng_Latn | 21,631 |
Studies on coating formula and waterproof properties of water proof coated paper | Three typical kinds of waterproof agents were selected and subsequently applied as additives in paper coatings.The coating formula and the waterproof properties of coated paper were studied through analyzing the Cobb value,static contact angle,ink absorption properties and picking velocity.The results showed that the waterproof properties and surface properties can be reached when No.2 waterproof agent is applied at 0.5 pph in bottom coating colors and No.1 waterproof agent at 7.5 pph in top coating colors.Furthermore,EPMA results indicate that the tight waterproof layer was formed in the coating surface by adding No.1 waterproof agent. | We generalize to the arithmetic Walsh transform (AWT) some results which were previously known for the Walsh---Hadamard transform of Boolean functions. We first generalize the classical Poisson summation formula to the AWT. We then define a generalized notion of resilience with respect to an arbitrary statistical measure of Boolean functions. We apply the Poisson summation formula to obtain a condition equivalent to resilience for one such statistical measure. Last, we show that the AWT of a large class of Boolean functions can be expressed in terms of the AWT of a Boolean function of algebraic degree at most three in a larger number of variables. | eng_Latn | 21,632 |
A Practical and Insider Secure Signcryption with Non-interactive Non-repudiation | Signcryption with non-interactive non-repudiation is a public key primitive which aims at combining the functionalities of encryption and signature schemes, while offering to a judge the ability to settle a repudiation dispute without engaging in a costly multi-roundprotocol. We propose a new RSA based identification scheme together with a strongly unforgeable signature scheme. We derive a practical and efficient signcryption scheme with non-interactive non-repudiation we show to be insider secure, under the RSA assumption and the Random Oracle model. The communication overhead of our signcryption scheme, compared to the corresponding signature scheme is one group element. | Production of aqueous dispersions of polymeric nanoparticles via heterogeneous radical polymerization in emulsion-type systems is of enormous commercial importance. The ability to reversibly destabilize such a latex is highly desirable, for example, to save transportation costs. Herein, a method for synthesis of photo-responsive polymer latexes that can be destabilized (leading to sedimentation) by only using UV irradiation (no addition of chemicals or change in the experimental conditions) and subsequently redispersed by stirring under visible light irradiation is described. The destabilization/redispersion mechanism relies on photoinduced trans-cis isomerization of the cationic diazene surfactant 2-(4-(4-butylphenyl)diazenylphenoxy)ethyltrimethylammonium bromide (C4AzoTAB) used in conjunction with the anionic surfactant sodium dodecyl sulfate. It is demonstrated that reversible destabilization can be achieved very rapidly (90 s residence time) employing continuous flow technology. | eng_Latn | 21,633 |
Etude du couplage chromatographie d'exclusion — diffusion de la lumière, 2. Application a quelques problèmes particuliers | A continuous light scattering detector coupled to a gel permeation chromatography (GPC) instrument (GPC-LS), as described in the preceding paper, is used to determine the hydrodynamic structure factor g′ of branched polystyrene samples and to establish the viscosity law for poly(methyl methacrylate), poly(vinyl chloride), and poly(vinyl acetate) by comparing the results from GPC-LS and GPC analysis (with molar mass calibration with linear, monodisperse polystyrene samples). | Abstract Beelen and coworkers in the Netherlands recently reported that visible light enhanced the rate of selective oxidation of mercaptoethanol by dioxygen, catalyzed by cobalt (II) tetrasulfonated phthalocyanine (CoTSPC). The Dutch workers speculated that visible light promoted disaggregation of CoTSPC, producing more of the catalytically active monomer. If Beelen and associates are correct, then it is possible that the values for the dimerization constants of CoTSPC are in error. since the values were measured spectrophotometrically in the region of the spectrum where Beelen contends visible light promtes disaggregation. To test whether the dimerization constants are altered by the spectrophotometer, the absorbance of a CoTSPC solution was measured with a diode array UV-VIS spectrophotometer. By comparing the spectrum of CoTSPC in the UV region with the tungsten lamp active and then inactive, one can see whether the visible light affects aggregation. It turned out that no change was observed in the sp... | fra_Latn | 21,634 |
Alginate Polyelectrolyte Ionotropic Gels-XVI. Kinetics and Chemical Equilibria Studies for Heterogeneous Ion Exchange of Polyvalent Metal Ions in Alginate Gel Complexes | The kinetics or chemical equilibria of exchange of Ca(II), Sr(II), Ba(I), Zn(II), Cd(II), Al(III), Fe(III), Se(IV), Ce(IV) and Th(IV) counter ions in alginate gel complexes by H+ ions have been investigated titrimetrically and conductimetrically at a constant ionic strength of 0.1 mol/dm3. The thermodynamic parameters have been evaluated and are discussed in terms of ionic radii and polarizability of the metal ions, coordination geometry, and stability of the gel complexes. | The present invention relates to a process for preparing a composition in the reaction of propylene, comprising based on: (a) propylene and 0wt% -10wt% of the C2 and / or C4-C20α- contacting in the first stage olefins under polymerization conditions to form component a; (b) the components a, ethylene and 3wt% -30wt% of one or more C3-C20α- olefins in the presence of a metallocene catalyst system in a second stage contacting under polymerization conditions to form a group B min; wherein the metallocene catalyst system comprises: (i) comprises 4, 5 or 6 metallocene compounds of metals, (ii) an activator, and (iii) a carrier material; and (c) obtaining component comprising a and component B of the composition based on the reaction of propylene, wherein the propylene-based composition in the reactor having a multimodal melting point. Also disclosed are articles comprising these compositions and the propylene-based propylene composition reactor. | eng_Latn | 21,635 |
Spectrophotometric Determination of Piroxicam and Tenoxicam in Pharmaceutical Preparations Using Uranyl Acetate as a Chromogenic Agent | Abstract New simple spectrophotometric methods for the determination of piroxicam, and tenoxicam in pharmaceutical preparations based on the reaction of piroxicam, and tenoxicam with uranyl acetate have been developed. The reagent forms yellow 1:2 complexes with piroxicam and tenoxicam in alcoholic medium. The complexes are stable for more than 24 hrs. The coloured species have absorption maxima at 395 and 435 nm, with molar absorptivities of 3.8 × 103 and 0.21 × 103 1mole−1 cm−1, and the mean percentage recoveries for authentic samples were 99.11±0.79, 98.78 ± 0.62 for piroxicam and tenoxicam, respectively. The site of chelation is given, and discussed. | Disclosed is a precursor composition comprising: a compound selected from a compound represented by the formula: Si(OR 1 ) 4 and a compound represented by the formula R a (Si)(OR 2 ) 4-a (in the formulas R 1 represents a monovalent organic group; R represents a hydrogen atom, a fluorine atom or a monovalent organic group; R 2 represents a monovalent organic group; and a is an integer ranging from 1 to 3, provided that R, R 1 and R 2 may be the same or different from one another) a thermally degradable organic compound; an element having a catalyst activity; urea; and the like. A porous thin film produced from the precursor composition is irradiated with ultraviolet ray, and then subjected to gas-phase reaction with a hydrophobic compound. A porous thin film thus prepared can be used for the manufacture of a semiconductor device. | eng_Latn | 21,636 |
Spectroscopic investigations of high-temperature, high-pressure model aviation fuels : Structure of jet fuels V | This paper describes progress in applying optical spectroscopic methods to the study of the chemical and physical processes that occur in aviation fuels under high-temperature, high-pressure conditions. | A method for preparing bis-carbamic acid alkyl esters of gelling agents, to a process for preparing the gelling agents. The steps are as follows: (1) The TDI 0.05mol and 0.10 ~ 0.12mol C4 ~ C22 aliphatic alcohol or an aromatic alcohol is added to 100 ~ 200mL stir an organic solvent; (2) the mixture at a temperature of 50 ~ 70 ℃ stirring was continued at a reaction time of 5 ~ 48h; after (3) the reaction, the solvent was distilled off to obtain a concentrate; vacuo (4) the hot concentrate was poured into a glass dish and placed in a dry 120 ~ 150 ℃ 5 ~ 12h dried under vacuum tank, i.e., to obtain a derivative of TDI-bis-carbamic acid alkyl esters gelling agents. Preparation of the gelling agent of the present invention can effectively gelling Russian oil spill into water, diesel, gasoline, soybean oil, peanut oil, cyclohexane, toluene, carbon tetrachloride, oil and other organic solvents, gelling agents added less rapidly solidified oil speed, high pour point oil cake strength, oil condensate thoroughly. | eng_Latn | 21,637 |
Reactivity of esters of 2-cyanoacrylic acid toward some free radicals | The rate constants for the addition of ·CH(Ph)CH2CCl3, ·CH2Ph, ·CH2Prn, and ·CCl3 radicals to the ethyl 2-cyanoacrylate molecule were determined by ESR spectroscopy using the spin trapping technique. | Abstract Photosensitivity based practical applications of chalcogenide glasses such as high resolution inorganic photoresists require thorough understanding of the relations between the glass structure and the etching kinetics. In this paper we report on the selective wet etching of thermally evaporated As2Se3 thin films carried out using amine based solutions. The relation between photo- and thermo-induced structural changes in thin As2Se3 films and the decrease of the etching rate, increase of the etching process' activation energy respectively, was determined. | eng_Latn | 21,638 |
On the Surface Chemical Reactions of Metal and Oxide XPS Samples at 300-400°at a High Vacuum Produced by Oil Diffusion Pumps(Chemistry) | Abstract Metal and oxide surface reactions formed by heating in the spectrometer at 300–400° at a vacuum of ca. 10 −9 Torr (oil diffusion pumps) were studied. As a result of spectral observations before and after heating, the metals studied were classified into five groups. In the first group, oxide films on the metal surface are easily evaporated because of the high vapour pressure of oxide; in the second, the oxide films are easily reduced in the spectrometer; in the third, the oxide film formed on the metal is reduced but the bulk oxide is not easily reduced; in the fourth, very stable oxide films are formed and the bulk oxide is also stable; and finally in the fifth, the oxide film formed on the metal is apparently reduced, yet the bulk oxide is very stable. | Using Chinese Cabbage(Brassica campestris syn. rapa L.ssp.Pekinensis(Lour) olsson) genome DNA as template,the major components of SRAP,such as concentrations of Mg2+,dNTPs,Taq DNA polymerase,primers and template,were optimized in this study by orthogonal design in five factors four levels respectively.The results showed that the optimum SRAP reaction system includes Mg2+ 3.0 mmol/L,dNTPs 0.2 mmol/L,DNA template 73.2 ng,Taq DNA polymerase 1.5 U and primer 0.2 μmol/L in the 25μL volume reaction.The most suitable protocol was initially denaturing at 94℃ for 5 min,then pre-amplifying at 94℃ 1 min,35℃ 1min and 72℃ 1 min for five cycles,finally amplifying for 35 cycles when the annealing temperature was adjusted to 50℃. | eng_Latn | 21,639 |
Polymer photonic technologies for optical communications | The impact of photonics in telecommunications is indisputably massive; however it relies on efficient cost reduction which is in turn only possible if significant cost savings are made at all steps in the development of the photonic device from the material to packaging. The PHOTOPOLIS consortium has identified polymer technology as the ideal solution for producing low-cost devices. The paper aims to discuss the status of polymer photonic components and subsystems able to generate, transmit and manage optical information in a cost effective manner. | Main problem ::: The microfill veneering of hybrid composite restorations has been indicated to improve esthetics. Also, polyethylene fiber reinforcement has been proposed for use in composite restorations in high-stress clinical situations. However, minimal information in the literature addresses the influence of such combinations on the resistance to fracture. The purpose of this study was to investigate the flexural strength of two composites, a microfill and a hybrid, the effect of their combination, and the influence of polyethylene fiber reinforcement. | eng_Latn | 21,640 |
Simultaneous determination of aspirin and salicylic acid in bulk aspirin and in plain, buffered, and enteric‐coated tablets by high‐pressure liquid chromatography with UV and fluorescence detectors | A quantitative high-pressure liquid chromatographic method that uses a reversed-phase column coupled to UV and fluorescence detectors was developed to determine aspirin and salicylic acid in bulk aspirin and in plain, buffered, and enteric-coated tablets. The aspirin was dissolved, filtered, and injected into the chromatograph. The UV absorbance of aspirin was determined at 254 nm, and the fluorescence of salicylic acid was measured at 425 nm. Excipients and impurities did not interfere. Recoveries of 100% were obtained for aspirin and salicylic acid from simulated tablet formulations. Results obtained by the USP XIX procedure and the proposed method were compared. The coefficient of variation for the aspirin analysis was 0.59%; for salicylic acid, it was 1.69%. The rate of hydrolysis of aspirin to salicylic acid in the solvents used was <0.05%/hr. | A microfluidic PCR device is presented capable of rapid temperature ramping and handling of sample volumes in the microliter and submicroliter range. The PCR chip comprises a straight micro channel in which a sample slug is periodically moved over three temperature zones. As part of the sample preparation a method for metering of the sample volume was developed. The PCR chip and the chips for sample preparation and fluidic actuation were fabricated by ultra-precision milling in polymer substrates. Computer simulations suggest that the sample slugs are heated or cooled on a time scale of some ten milliseconds when transported to a different temperature zone. The fluidic actuation based on a ferrofluid transducer is capable of positioning the sample volumes with a high accuracy after a large number of cycles. The design developed should be ideally suited for fast PCR of small sample amounts in a highly parallel manner. | eng_Latn | 21,641 |
TERMINATION PROCESS AND THE TERMINATION PARAMETER k t OF METHYL METHACRYLATE BULK RADICAL POLYMERIZATION | In this work the exact k_t data during the whole process of MMA bulk radical polymerization have been determined under unsteady state by using the post effect technique and ESR method. The effect of the micro-environment of radicals on the termination is discussed. | Abstract The telomerization in emulsion of styrene is studied with two transfer agens: thioglycolic acid and 1,1,2,2-tetrahydro perfluorooctane thiol. The influence of the telogen-amount vs the degree of telomerization, that of the surfactant concentration and that of the nature of the initiator are investigated. The telomerization of this monomer with these aliphatic mercaptans is possible in aqueous medium whatever the solubility of the thiols in water. Transfer constants of both these mercaptans were determined as 1.60 and 1.16 for thioglycolic acid and the fluoronated thiol, respectively. © 1997 Elsevier Science Ltd. All rights reserved | yue_Hant | 21,642 |
Overstressed interatomic bonds in stressed polymers | Infrared (IR) spectroscopy is used to find how the applied mechanical stress imposed upon a sample is distributed among the interatomic bonds. The distribution is highly heterogeneous: 80–95% of the bond population experience stresses close to the applied stress, the stress on the rest of the bond population varies over a wide range and reaches 1000–2000 kg/mm2. The overstressed interatomic bonds lie in the amorphous regions of the polymer and are oriented in the direction of the mechanical force. The maximum stress on interatomic bonds is determined by the magnitude of the breaking stress on them. The breaking stress is shown to be a function of the applied stress, time, and temperature. This dependence is due to scission of stressed bonds induced by thermal fluctuations. | Abstract The vulcanization of butyl rubber by p-quinone dioxime oxidized by red lead and tetrachloroquinone was investigated. The maximum physical effective crosslinking density of the vulcanizates appeared to be when p-quinone dioxime and the oxidizing agent were equimolar. The formation of one physical effective crosslink required one molecule of p-quinone dioxime. Chemical reactions are suggested for the vulcanization steps. | eng_Latn | 21,643 |
A calorimetric study of the process of formation of a supramolecular high-density polyethylene structure in mixtures with different oxides after plastic deformation under high pressure | Mixtures of ultrahigh-molecular-weight polyethylene with 95 wt % oxides of different elements were subjected to plastic deformation under the pressure of 1 GPa at a high pressure device of the Bridgman anvil type and thermal effects were studied using the DSC technique. Thermograms contained exothermic peaks with a maximum at 50–90°C related to cold crystallization of the polymer. The process of polymer fusion was described by two peaks with the maximums at T 1 = 125–128°C and T 2 = 136–139°C. The low-temperature peak was related to fusion of a structure with high amounts of defects formed on the oxide surface. | To deal with the market demand and the production organization feature of steel making enterprises,we formulate the optimization of charge design as a cluster analysis problem with quality constraints on chemical compositions.A particle-swarm-optimization-based(PSO-based) solution is proposed for reducing the dimensions based on the principal component analysis(PCA) techniques.The range constraints of chemical compositions for products with similar quality are introduced in terms of traditional process constraints,due time constraints and furnace capacity constraints,etc.The solution adopts an integration schema for charge plan and quality design.It performs the cluster analysis for candidate products with similar chemical compositions and constraints to realize the optimal charge design under quality constraints on steel products of multiple varieties and in small batch demands. | eng_Latn | 21,644 |
Excimer formation in pyrene labeled hydroxypropyl cellulose in water: picosecond fluorescence studies | Excimer formation of pyrene chromophores in an aqueous solution of hydroxypropyl cellulose has been studied with a picosecond time-resolved fluorescence spctrophotometer. The time-resolved spectra show two types of broad structureless fluorescence bands at (1) 420 nm in a short time region (0-7 ns) and (2) 470 nm in the time region after 50 ns. The latter is the well-known sandwich-type pyrene excimer, and the other is assumed to be a one-center-type excimer similar to those observed in several other molecular assemblies such as LB films, vapor-deposited films, and single crystals. This is the first report on the detection of such excimers in a dilute polymer solution. | □ It was shown that vinyl polymers form good bases for in vitro sustained-release matrices, and that the character of the release curves is basically in line with their PH–solubility profiles. For a flow cell, the release curves may be approximated by the equation: In (m/m0) = –K(t − ti), where m is the amount not dissolved, m0 is the initial drug content, K is a dissolution constant, t is time, and t, is a lag time. Furthermore, it was shown that K is a function of tablet hardness (H) and polymer content (Q, percent). This functionality is well represented by the equation: In K = αH + γ in Q + ϵ, where α, γ, and ϵ are polymer-dependent parameters. Matrix erosion is represented by an exponential decay: (p/p0) = exp(–Dt + a), where p is the amount not eroded, p0 is the initial weight, D is an erosion constant, and a is a soluble polymer-dependent parameter. In the case of these soluble polymers, K is not solely a function of D. | eng_Latn | 21,645 |
Effect of structure on coating performance properties of novel alkylenedioxydiphenol based epoxy resins | Abstract Although epoxy resins exhibit a wide range of useful properties for protective coatings on metal substrates, an increasing trend in the coatings industry toward more formable coatings places a severe burden on the traditional bisphenol. A based epoxy resins. Presented in this work are the results of experiments with a new series of epoxy resins based on alkylenedioxy diphenols demonstrating the relationship between coating performance properties (formability, chemical resistance, and adhesion) and structural parameters such as resin backbone flexibility, degree of phenol/formaldehyde crosslinkmg, and concentration of OH groups in the backbone of epoxy resins. Optimizing the three structural parameters for the new resins results in substantial improvements in coating performance properties over the traditional bisphenol A based resins. | Abstract Methods of estimating the concentration of effective network chains from the stress—strain behaviour of elastomers both dry and swollen in solvents are discussed. It is pointed out that while measurements in uniaxial extension are more difficult to carry out experimentally than measurements in uniaxial compression, they are preferred because they can provide more information about the behaviour of the elastomer. An equation is presented for relating the stress—strain behaviour of swollen composites containing inert fillers to the behaviour of a gum having the same degree of crosslinking; experimental data on SBR—glass bead composites are presented which indicate that the equation is applicable. | eng_Latn | 21,646 |
Diagnosis of hemolytic disease by electrophoresis of erythrocyte lactate dehydrogenase isoenzymes on cellulose acetate or Agarose. | We determined the LD-1/LD-2 isoenzyme ratio in hemolysates of erythrocytes by electrophoresis on cellulose acetate and on agarose. A ratio exceeding 1.0 was found with the former but not the latter. Results were similar for in vitro models of hemolytic disorders. Using cellulose acetate electrophoresis, we determined the predictive value of data on total LD activity and of the LD-1/LD-2 ratio in diagnosis of hemolytic disease in 100 patients. The sensitivity of the "flipped" LD-1/LD-2 ratio was only 58%, the specificity was 93%, and the predictive value was 74% for diagnosis of hemolytic disease. A normal total LD activity is highly predictive (92%) for ruling at the presence of hemolytic disease. | A method for continuously producing a polyester by direct esterification, characterized in that the refining device is not attached to the recovery of the excess ethylene glycol recovery purification systems, and will be returned directly used as the starting material resulting polycondensation tank is condensed glycol. Fresh ethylene glycol was added to the slurry preparation tank seaming two and a wet condenser of the final amount is added by the latter 35 to 50% of the total amount, the molar ratio of TPA to EG of the total added 1.02 to 1.10. Quality of the resulting polyester is the same as the conventional direct esterification of a polyester production, and equipment investment, operating costs and raw material consumption is greatly reduced. | eng_Latn | 21,647 |
Effect of Light Intensity and Other Factors on the Color of Frozen Prepackaged Beef | Abstract Color shelf life of prepackaged frozen retail beef cuts exposed to light (0–2000 lx) at temperatures between −1 and −40°C varied from less than 1 day to more than 90 days, depending on light intensity and temperature. Color shelf life increased with decreasing light intensity at temperatures above −29°C; for example. 100–250 lx gave 5–10 days shelf life at −18°C At −40°C color shelf life was unaffected by light intensity. Carbon monoxide pretreatment produced bright red appearance with greatly improved color shelf life. Other factors tested included two kinds of fluorescent light (no difference), high and low oxygen permeability films (no difference) and the effect of thawing (no effect on appearance). | The comparison of three most popular kinetic packages by the results of the numerical simulations of autonomous cw ::: HF (DF) chemical lasers was carried out The differences in the small signal gains obtained by means of 1976-1977 ::: kinetic package and at 1982 (2002) package reach about of 40...60% for HF laser, and about of 70...80% for DF laser. ::: The comparison of rate constants for separate processes was made. | eng_Latn | 21,648 |
Influence of Nanoparticle Additives on the Fragility of Polymer Glass Formation and the Buchenau Relation | We investigate the impact of the addition of nanoparticles (NP) on the fragility of a model glass-forming polymer melt by molecular dynamics simulations. We find significant changes in fragility for nanoparticle volume fractions $\phi$ exceeding $\approx$ 5%, where fragility changes correlate with the inverse variance of the magnitude of the Debye-Waller factor $$, a measure of local"stiffness"fluctuations. We also confirm the validity of the Buchenau relationship between $$ and the structural relaxation time $\tau$ for all $\phi$ and polymer-NP interaction types. | Abstract The application of the new smoothing routine based on adaptive binomial filter for Scanning Auger Microscopy has been investigated. The main advantage of the adaptive binomial filter is the possibility to reduce the noise without noticeable signal broadening. Experimental Auger images of the various samples (Au films on alumina and porous silicon films) were processed by this routine. It was demonstrated that the employment of the new smoothing routine improves the visual quality of chemical images and elemental scattering diagrams. The detailed surface chemical composition of the samples investigated was finally revealed by using elemental scattering diagram analysis. | eng_Latn | 21,649 |
Field-Effect Transistors Based on a Benzothiadiazole−Cyclopentadithiophene Copolymer | We present a solution processed organic field-effect transistor based on a benzothiadiazole (BTZ)−cyclopentadithiophene (CDT) copolymer with mobilities as high as 0.17 cm2/Vs and an on/off ratio of 105. This pronounced performance together with the lack of macroscopic order in the thin film makes this conjugated copolymer an attractive candidate for low-cost organic electronics due to its facile processing. | A new time-domain procedure is suggested for obtaining reduced-order models of linear time-invariant discrete-time systems. The procedure is based on presenting a new form of continued-fraction expansion (CFE) about z = 1 and z = a alternately, and deriving a realization form for the CFE. An algorithm is presented for obtaining the new CFE of the z transfer function of a linear discrete-time system from its state-space model directly, without having to determine the corresponding rational z transfer function. Also presented is a systematic approach to deriving two similarity transformation matrices: one is used to transform a state-space model from a general form to the CFE canonical form, and the other is used to transform a state-space model from the phase-variable canonical form to the CFE canonical form. Finally, an approximate aggregation matrix is constructed to relate the state vector of the original system to that of a reduced model obtained by the present method. The proposed procedure is illustr... | eng_Latn | 21,650 |
Transformation of 3-(3-arylalkylcarbamoyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-1-yl)propanenitriles into amides and acids | A mixture of hydrochloric and acetic acids depleted in water was proposed to effect stepwise transformation of 3-(3-arylalkylcarbamoyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-1-yl)propanenitriles into the corresponding amides and then into the acids. The procedure turned out to be efficient with 3-[(2-phenylethyl)-carbamoyl] derivatives, whereas the reactions with benzylcarbamoyl analogs were accompanied by partial or complete debenzylation. | Abstract Copolymers of styrene and methacrylic acid (MAA) with widely differing compositions have been studied by thermal volatilisation analysis (TVA) and thermogravimetry. The condensable volatile degradation products have been identified after separation by subambient TVA. The cold ring fraction (tar/wax products) and the structural changes in the residue in the course of degradation have also been examined. The copolymers are intermediate in stability between polystyrene (PS) and poly(methacrylic acid) (PMAA). The degradation products are mainly those expected by comparison with those obtained from the homopolymers, but methacrylic acid is formed in greater amount in the copolymer degradation and the distribution of MAA units leads to less intramolecular dehydration. Anhydride rings formed, however, reduce the zip length of depolymerisation to monomers, and both rings and isolated MAA units reduce the possibilities for transfer by polystyryl radicals. | eng_Latn | 21,651 |
Pyrophosphate-dependent Phosphofructokinase : Its Oligomeric Forms in Mature Green Tomato Fruit | Pyrophosphate-dependent phosphofructokinase (PFP: EC 2.7.1.90) from mature green tomato fruit was purified by a DEAE-Sephacel column and preparative gel electrophoresis. Tomato PFP was composed of oligomeric forms and the tetramer of 243–262 kDa molecular mass was predominant. Treatment of PFP with 20 mM pyrophosphate effectively dissociated oligomers into monomers as shown by the gel filtration patterns of a Sepharose 6B column. Kinetic analysis indicated that tomato PFP had a Km of 0.3 mM for glucose-6-phosphate and a Ki of 1.3 mM for pyrophosphate. About 11-fold activation was attained by fructose-2,6-bisphosphate, though there was no activation in the direction of the reverse, gluconeogenesis reaction. Various effectors had a role to control the PFP activity in the direction of either the forward or reverse reaction. | Dynamic characteristic of a system have to be obtained so as to offer the reliable data for the system dynamic modification and dynamic optimum design. The system modal parameters identification can be changed into the global optimization problem in wavelet plane because the wavelet ridges can carry much information of system characteristic parameters. Firstly, the paper will introduce the so-called PSO (Particle Swarm Optimization) technique into the modal analysis and propose the PSO wavelet ridge extraction algorithm. Furthermore, the formulas identifying modal parameters from a wavelet ridge are derived and computation steps were given. The simulation experiments are implemented in order to evaluate precision of this method and the robustness of noise. Finally, the proposed method applies to the modal parameters identification of a watermelon to explore the effectiveness. The experiment results prove the method is precision and insensitive to noise. | eng_Latn | 21,652 |
The Effect of Condensation on Heat Transfer Through Polyethylene Film | ABSTRACT THE effect of condensation on polyethylene film was studied in a laboratory model. Overall heat transfer was determined as a function of condensation rate, orientation of polyethylene surface with respect to the horizontal, and filmwise vs. dropwise condensation for three air velocities (0.5, 0.8, 1.6 m/s). Heat fluxes were partitioned into radiative and conduction/convection components with thermal transmissivities of the water/polyethylene composite determined. In 14 of the 15 tests conducted, heat transfer increased in the presence of condensation. Thermal transmissivities for the wet tests approached zero in nearly every case. Increasing condensation rate was found to increase heat transfer as would be expected. The effect of orientation on overall heat transfer was determined to be primarily due to buoyancy between the polyethylene layers while the effect of filmwise vs. dropwise condensation appeared to be negligible. | The photopyroelectric method in a non contact detection configuration is proposed to study water migration in starch sheets. This allows the exchange of humidity between the moist atmosphere and the starch sample during the experiment. The sensitivity for the total water content measurement was about 0.3%. A theoretical model was developed, taking into account a continuous depth profile of humidity in the starch sample. A water profile in the material and its evolution in time were evidenced when exposing one side of the sample to a humid atmosphere. | eng_Latn | 21,653 |
The role of xylulokinase in Saccharomyces cerevisiae xylulose catabolism. | Many yeast species have growth rates on D-xylulose of 25-130% of those on glucose, but for Saccharomyces cerevisiae this ratio is only about 6%. The xylulokinase reaction has been proposed to be the rate-limiting step in the D-xylulose fermentation with S. cerevisiae. Over-expression of xylulokinase encoding XKS1 stimulated growth on D-xylulose in a S. cerevisiae strain to about 20% of the growth rate on glucose and deletion of the gene prevented growth on D-xylulose and D-xylulose metabolism. We have partially purified the xylulokinase and characterised its kinetic properties. It is reversible and will also accept D-ribulose as a substrate. | True 100% grafted polymers were prepared in a two-stage emulsion polymerization process. Microgels of styrene crosslinked with divinylbenzene, methyl acrylate crosslinked with divinylbenzene, and acrylonitrile crosslinked with methylene-bisacrylamide were used as first stage polymers, and the grafting of styrene and acrylonitrile were studied. The polymers were analyzed as microsols by limiting viscosity number and by ultracentrifuge measurements. In the ultracentrifuge the quantitative separation of crosslinked particles from linear polymers was demonstrated. From a study of the polymerization conditions which result in a single sedimenting component in the ultracentrifuge, 100% grafted polymers were synthesized. The results indicated that in order to obtain 100% grafting initiation must be by free radicals present in the polymer particles with none from residual catalyst or by thermal initiation. The existence of polymeric free radicals of lives greater than 100 days is demonstrated. | eng_Latn | 21,654 |
THE REDUCTION OF CERIC SULPHATE SOLUTIONS BY IONIZING RADIATION | The yield of cerous ions formed in the reduction of ceric ion in sulphuric acid solutions by X and γ-radiation is independent of cerous and ceric ion concentration, the energy of the radiation, the rate of energy absorption over a wide range, the acid concentration, and the presence of oxygen. A small negative temperature coefficient has been observed. The over-all stoichiometric equation isHydroxyl radicals postulated to be produced by the radiation form water and oxygen gas. The lower limit of concentration independence is below 2 × 10−6 moles per liter. | This paper introduces the theories of cationic modification of linen and puts forward the optimal process conditions of cationic modification and dyeing of linen through orthogonal experiment and analysis. By comparing and analyzing the dyeing samples of the cationised linen and non-cationised linen, it also shows that cationic modification has clear effect to enhance the dyeing capability of rhubarb on linen. | yue_Hant | 21,655 |
A polyolefin composition with improved stress whitening resistance | The present invention relates to a polyolefin composition having an improved stress whitening resistance without loss of a good balance of impact strength and stiffness. | Microechography was used to characterize crosslinking gradients in photopolymers, because this technique can produce acoustic images of amplitude variations of local mechanical properties. A frequency of 25 MHz was chosen due to the high absorption of the investigated material at high frequencies. Two sets of samples were studied. The former, which had been polymerized through a test mask and displayed sharp gradients, were used to check the sensitivity of the technique; the latter were insulated through a chromium apodizing filter with a radial density variation and allowed the resolution of the apparatus to be determined. Results obtained on the exposed sample surfaces and on cross sections showed that this technique is well suited to the study of crosslinking gradients in, photopolymers despite the resolution loss resulting from the use of low frequencies. The method is exemplified by the study of mask pattern transfer into a polymer. | eng_Latn | 21,656 |
Fabrication of Fire Resistant Transparencies | Abstract : Describes methods of casting sheets, curving the sheets into the required contours and then laminating the epoxy transparencies to other plastics. Laminated side windows were made with epoxy as the outer surface and polycarbonate as the inner surface. Identical sized windows were also made using a single cast monolithic sheet of EX-112. Tests of the composite transparencies consisted of ballistics tests, determination of heat distortion temperature, limiting oxygen index, buring rate, thermal conductivity and the coefficient of thermal expansion. Results indicated a substantial improvement in fire resistance over state-of-the-art acrylic transparencies. | We report an experimental observation of Poisson's spot with pseudo-thermal light. The experimental results show that the diffraction pattern disappears in the intensity distribution behind the opaque disc but emerges through both auto-correlation and cross-correlation intensity measurements. The auto-correlation scheme can take care of both better visibility and higher resolution of the diffraction pattern under the condition that the thermal light source has a larger spectral bandwidth. | eng_Latn | 21,657 |
All-optical full-color displays using polymer nanofibers. | We report a number of crossed nanofiber structures for full-color micro/nanodisplays, which were formed by assembling flexible poly(trimethylene terephthalate) (PTT) nanofibers under an optical microscope with the assistance of micromanipulators. The color pixels of the displays consist of micro/nanometer sized color spots in a radius of 300−1500 nm, which were realized through crossed junctions of the PTT nanofibers. The colors of the spots were tuned by changing the power ratios of the launched red, green, and blue lights. We further present a new way to develop white light illumination by combination of red, green, and blue lights with assembly techniques and low production costs. | The synthesis and self-assembly behavior of biohybrid ABC triblock copolymers consisting of a synthetic diblock, polystyrene-b-polyethylene glycol (PSm-b-PEG113), where m is varied, and a hemeprotein, myoglobin (Mb) or horse radish peroxidase (HRP), is described. The synthetic diblock copolymer is first functionalized with the heme cofactor and subsequently reconstituted with the apoprotein or the apoenzyme to yield the protein-containing ABC triblock copolymer. The obtained amphiphilic block copolymers self-assemble in aqueous solution into a large variety of aggregate structures. Depending on the protein and the polystyrene block length, micellar rods, vesicles, toroids, figure eight structures, octopus structures, and spheres with a lamellar surface are formed. | eng_Latn | 21,658 |
Risk of ovarian cancer in relation to use of phenolphthalein-containing laxatives | We examined ovarian cancer risk in relation to use of phenolphthalein-containing laxatives in 410 epithelial ovarian cancer cases and 713 controls. Compared to women who never used a laxative, ever use of a phenolphthalein-containing laxative was not associated with an increased risk of ovarian cancer (odds ratio, OR, 1.1, 95% confidence interval, CI, 0.9–1.4). Risk was slightly, but not significantly, higher with more frequent use (OR 1.2 for 75 or more days of use). When women who used non-phenolphthalein containing laxatives was used as the reference group, the associations were slightly, but not significantly larger (OR 1.4 for any use of phenolphthalein-containing laxatives and OR 1.5 for 75 or more days of use) © 2000 Cancer Research Campaign | A study of the effects of surface treatment of polypropylene on the deposition of thin metal films is presented. The polypropylene samples were treated in a low-pressure air plasma in one case and sputtered by argon ions in the other case. XPS was used to detect compositional surface modifications. Plasma treatment leads to surface oxidation, whereas the sputtering results in oxygen-free surfaces for in-situ analysis. After surface treatment, thin films of Mg, Ca and Ce were deposited. Depending on the surface treatment, we find indications for different bonding mechanisms and very different sticking probabilities. For the case of oxidized surfaces, the formation of a metal-oxygen-polymer complex is anticipated, whereas for oxygen-free surfaces a metal-carbon bond is likely to be formed. | eng_Latn | 21,659 |
The photosensitive resin composition for a method of embossing process and an organic layer formed on the substrate for | The present invention provides a photosensitive resin composition and a method for forming an organic film on the substrate used. Since the photosensitive resin composition used for embossing comprises erythritol alcohol monomer or oligomer, and thus the organic film made of the photosensitive resin composition is formed having improved restoring force. Thus, the photosensitive resin composition is suitable for the imprint process. | Abstract During the past two decades, the use of immobilized glucose isomerase for the production of high-fructose corn syrup has evolved into a highly optimized industrial process. The desire for higher process temperatures has stimulated the screening of extreme thermophilic organisms for more thermostable glucose isomerases; protein engineering techniques have also been successfully used to develop more thermostable enzymes. | eng_Latn | 21,660 |
Methods for preparing ink sets curable pigmented inkjet | Set of inkjet inks curable pigmented including an ink CI yellow injection containing Pigment Yellow 150, an inkjet ink cyan comprising a pigment of β-copper phthalocyanine and a printing ink magenta injection comprising a mixed crystal in which a first quinacridone and a second quinacridone enter the same crystal lattice being unsubstituted quinacridone CI Pigment Violet 19 present as the first quinacridone in the mixed crystal in an amount of between 75% and 95%, as measured by Probe- MS. | The experiment was conducted to optimize the conditions of A-PAGE for isolating salt soluble proteins of foxtail millet.10 foxtail millet varieties were used for A-PAGE.A number of A-PAGE electropherograms were obtained at different levels of dosage of catalyst,gel concentrations,cross-linkages,injecting volumes,pH of gel buffer,and the use of inspissate gel.The optimal conditions for A-PAGE were raised after deliberate investigation.Detailed criteria were as following: dosage of 3% H2O2 1 μl/ml gel,gel concentration 13%,cross-linkages 4%,pH of gel buffer 3.7,and the injecting volumes between 20 and 30 μl.Furthermore,the use of inspissate gel enhanced the resolution of gel electropherograms. | eng_Latn | 21,661 |
Regulation of the reovirus RNA transcriptase by a viral capsomere protein. | Abstract Reovirus subviral particles combine spontaneously in vitro with soluble viral proteins to form a particle which is similar to the intact virion in structure and buoyant density. The RNA transcriptase activity which is manifest in the subviral particle becomes masked in the reassembled virions. The viral protein responsible for these structural and functional alterations has been identified as the major outer capsomere protein, σ3. | We present a study of resonant Raman scattering of trans-(CH${)}_{\mathrm{x}}$ chains embedded in polyvinylalcohol in the two different systems of polyvinylene and polarizer K. These systems show marked differences as well as common properties and are analyzed and compared with polyacetylene within the frame of the amplitude-mode model. The combined analysis of the different systems of polyacetylene having an identical phonon propagator but different types of inhomogeneity makes it a powerful tool for broader understanding of conjugated polymers and demonstrates once more the strength of the amplitude-mode model. We show that on top of the resonant Raman scattering (RRS) of polarizer K, a fine structure is resolved, which originates from vibronic transitions. Both the appearance of this vibronic structure in the RRS and its absence from the absorption spectrum are fully accounted for. The spectral sensitivity of RRS to temperature and laser intensity is shown to be the result of the increase in damping. | eng_Latn | 21,662 |
Metallic carbide surface coating for the sampling cone of a mass spectrometer | A sampling cone 3 and/or a cone gas cone 4 and/or an extraction cone 8 of a mass spectrometer are disclosed having a metallic carbide surface or coating. The metallic carbide surface or coating may comprise a transition metal carbide, a carbide alloy, or a mixed metal carbide alloy, but preferably comprises titanium carbide. The coated surface is intended to reduce adsorption of material on contact with the surface of the sampling or extraction cone. | The present invention provides a method for obtaining improved hair feel. The method comprises administering to the hair a composition, said composition comprising: (a) a particular cationic guar gum polymer; specific cationic copolymer (b); (c) anti-dandruff active; (d) Beauty acceptable carrier; (e) a surfactant; wherein the (a) :( b) weight ratio of from about 1000: 1 to about 3.5: 1; and wherein (a) + (b) by the sum of the total weight of the composition in an amount from about 0.0001% to about 0.7%. Upon dilution with water the composition, the composition forms a coacervate particles, and the agglomerated particles having a layer extrusion flow viscosity of approximately 1cP to about 100cP. Percentage coacervate particles floc size greater than about 20 microns, from about 1% to about 60%, and anti-dandruff on the scalp deposited as active material of at least about 1μg / cm2. | eng_Latn | 21,663 |
Laser action induced in a nanostructured polyaniline LED | Direct electrical pumping of polymer lasers is considered to be a great challenge. Our recent experiments indicate the laser action in a nanostructured polyaniline diode. This has been identified as an electrically pumped random laser, in which a conducting polymer (nanostructured polyaniline) plays the role of an active medium. The device of a simple LED architecture is directly electrically powered at a low voltage of 5–15 V. Above the threshold voltage (4–8 V) and the electrical energy pumped (75–100 W), different laser modes are generated, including the emission of nearly monochromatic light. This is the first electrically pumped random laser, based on a nanostructured conductive polymer – polyaniline. These results are groundbreaking in the field of polymer lasers, which are directly electrically powered. The impact of the findings is not limited either to this particular device or to the specific material used. | Abstract A technique suggested by Mola and Heras of analyzing thin film size effect data is used to characterize the structure of thin polycrystalline metal films. A linear least-squares analysis of the product of resistivity and thickness versus thickness allows a consistent determination of the size effect parameter α. Annealing studies (130–460 K) on gold films (120–1150 A) yield temperature-independent values of the reflection coefficient both before and after annealing and allow the annealing to be characterized quantitatively. | eng_Latn | 21,664 |
Imaging Diagnosis and Interventional Treatment of Pulmonary Arteriovenous Fistula | To sum up and analyse imaging methods of chest radiography,contrast bubble echocardiography,chest CT,MRA and DSA for diagnosis of pulmonary arteriovenous fistula,and to explore application of the embolus such as coils,detachable balloon,amplatzet vascular plug and homemade double-umbrella occluder in the interventinal treatment,and also operation technic,attentions,complications,following up and reccurence. | With a view to the problems in the performance testing of fluorocarbon coatings of metallic wall screen, including verification of the resin systems used in vanishesand top-coats, determination of content of polyvinylidene fluoride ( PVDF) , and arbitration of color variation of coatings with angles, efforts were made to modify currently available methodsspecified in relevant national standards for performance tes-ting of coatings. At the same time, qualitative analysis of the varnishesand top-coats by Fourier transformation infrared (FT-IR) spectrometry and quantitative analysis of the content of PVDF by differential scanning colorimetry were conducted. And the variationin the color of the coatings was examined using a 5-angle spectrophotometer. This would be helpful to resolving the above-mentioned problems concerning the performance testing of the flu-orocarbon coatings of metallic wall screen. | eng_Latn | 21,665 |
Microstructure of polymeric electrolyte PEU-LiClO4 studied by positron spectroscopy | The positron lifetime spectra and ionic conductivity have been measured for polymeric electrolyte PEU-LiClO4 as a function of temperature in the range of 120≈360 K and as a function of Li-salt concentration at room temperature. From the temperature dependence of positron annihilation parameters, the glass transition and subtransition are observed, and the glass transition temperatureT g of pure PEU is determined to be 240 K. AboveT g, the free volume hole size dramatically increases with temperature. The variations of positron annihilation parameters and ionic conductivities with respect to Li-salt concentration at room temperature indicate that the Li salt mainly diffuses into the amorphous region in PEU-LiClO4. The increase of Li salt concentration brings about an increase in the number of carried ions, and a reduction of the fractional free volume. | The present invention is directed to phosphatidylinositol or lysophosphatidylinositol concentration indicators relates to efficacy evaluation method of a medicament having a therapeutic or prophylactic effect for a disease EL activity is associated. Further, the present invention relates to a kit for use in screening methods and method of the EL active inhibitors using phosphatidylinositol. | eng_Latn | 21,666 |
PVC experiments-first rate lab apparatus from plastic plumbing, adhesive, and imagination | The present paper is intended to assist faculty who wish to develop undergraduate instructional laboratory apparatus, but who have only limited financial resources available. The paper attempts to make interested faculty aware of how simple, low cost, readily available PVC materials and products can be utilized to create first rate laboratory experiments. Although much of the information provided might be familiar to some home owners who undertake their own renovations and repairs, it is felt that the ideas expressed here may prove to be a revelation to many faculty who had previously considered the purchase of packaged experiments as their only option. Tips are given on types and sources of PVC, fabrication techniques and some example experiments are discussed. | In the paper,the separation principle,the history and the newly development of the corrugated plates coalescing oil-water separation technology are summarized,discussion on the difficulties and the problems met in the research progress was done,some proposals are also given for the further research as well in the paper. | eng_Latn | 21,667 |
Chemical modification of polymers to improve flame retardance—I. The influence of boron-containing groups | Polystyrene has been silylated by a two-stage process, involving reaction with n-butyl lithium in the presence of tetramethylethylenediamine, followed by reaction with trimethylchlorosilane, dichlorodimethylsilane or trichloromethylsilane. The degree of silylation can be increased if the polystyrene is initially brominated, in the presence of thallic acetate, prior to lithiation and silylation. The surfaces of poly(vinyl alcohol) films have also been modified with a number of chlorosilanes. Flame retardant effects of these modifications have been assessed by measurements of char yields, weight losses and limiting oxygen indices. The limiting oxygen indices of the silylated polymers are all significantly higher than those of the parent polymers and small char yields are obtained on combustion of them. Silicon is shown to have a greater effect on flame retardance in the presence of halogen for each of the modified polymers. | Abstract Pressure and internal energy of a fluid composed of polarizable Stockmayer molecules have been calculated by a molecular dynamics computation as well as by thermodynamic perturbation theory. It is found that the effect of molecular polarizability is underestimated by perturbation theory. | eng_Latn | 21,668 |
Tunable polymeric Bragg grating filter using nanoimprint technique | A tunable wavelength filter was proposed and demonstrated by using the ultraviolet nanoimprint technique. It consists of a Bragg grating in polymer waveguides and a heating electrode. The creation of the grating was substantially simplified with the introduction of a smart imprint stamp containing a waveguide pattern integrated with the grating pattern. The center wavelength of the filter was successfully tuned by taking advantage of the thermooptic effect in polymers, which was induced by supplying electrical power to the electrode. For the fabricated device, a transmission dip of ∼15dB and a 3dB bandwidth of 0.8nm were obtained at the Bragg wavelength of ∼1560nm. The achieved thermooptic tuning rate was ∼0.28nm∕mW, while the center wavelength was shifted from 1560nm to 1558nm with the electrical power consumption of 7mW. | We have studied segregation and embrittling energy of sp ::: elements of the 3rd, 4th and 5th period (Al, Si, P, S, Ga, Ge, ::: As, Se, In, Sn, Sb and Te) at the Sigma5(210) grain boundary ::: (GB) in fcc nickel and the segregation of these impurities at ::: the (210) free surface (FS). Full relaxation of the geometric ::: configuration of the GB and FS without and with impurities has ::: been performed and the effect of impurities on the distribution ::: of magnetic moments has been analysed. We determined the ::: embrittling energy from the difference between the GB and FS ::: binding energies on the basis of the Rice Wang model. and we ::: separated embrittling energy into the chemical and mechanical ::: part. | eng_Latn | 21,669 |
Hydroboration polymerization of dicyano compounds | SummaryHydroboration polymerization of various α,ω-dicyanoalkanes with thexylborane produced the corresponding poly(cyclodiborazane)s, that consist of boron-nitrogen four-membered rings. The structures of the obtained polymers were confirmed by spectroscopic analyses such as 1H-, 11B-NMR and IR spectra. From the result of thermogravimetric analysis of the polymer prepared from adiponitrile and thexylborane, 12% of the inorganic materials remained after heating at 900°C. *** DIRECT SUPPORT *** AEB03051 00003 | A method of treating wood pulp comprising a step of adding at least one biopolymer phase oxygen delignification during a bleaching stage between the bleaching stages, or after the pulp has been bleached but before drying the paste, adding said biopolymer in an amount of 5.0 kg / adt to 20.0 kg / adt, based on the total amount of paste, wherein said biopolymer is starch modified by chemical reaction of etherification. | eng_Latn | 21,670 |
Dynamic optimization of semicontinuous emulsion copolymerization reactions: Composition and molecular weight distribution | Iterative dynamic programming is used to compute optimal monomer and CTA feed profiles to produce polymer with pre-specified copolymer composition and MWD. This approach can deal with constrained optimizations of systems described by complex mathematical models, as those needed for the emulsion copolymerization kinetics, especially when the computation of the whole MWD is included. The proposed approach is applied to the semicontinuous MMA/BuA emulsion copolymerization, using dodecanethiol as CTA, allowing the effective computation of feed policies for the production of constant composition copolymer with well-defined MWDs. | The present invention relates to a special process for the continuous preparation of a mixture of organoalkoxysiloxanes, starting from (i) an organotrichlorosilane or a mixture of organotrichlorosilanes or a mixture of at least one organotrichlorosilane and tetrachlorosilane, (ii) water and (iii) alcohol. DOLLAR A Further, the present invention relates to mixtures of organoalkoxysiloxanes, which are obtainable by the continuous process and the use of such mixtures. | eng_Latn | 21,671 |
Butyl vinyl ether-1-amino-3-[2-(vinyloxy)ethoxy]-2-propanol cooligomer as a stabilizer of mazut-coal blended fuel | Butyl vinyl ether-1-amino-3-[2-(vinyloxy)ethoxy]-2-propanol cooligomer was prepared and studied as a stabilizer of mazut-coal blended fuel. | A method for preparing bis-carbamic acid alkyl esters of gelling agents, to a process for preparing the gelling agents. The steps are as follows: (1) The TDI 0.05mol and 0.10 ~ 0.12mol C4 ~ C22 aliphatic alcohol or an aromatic alcohol is added to 100 ~ 200mL stir an organic solvent; (2) the mixture at a temperature of 50 ~ 70 ℃ stirring was continued at a reaction time of 5 ~ 48h; after (3) the reaction, the solvent was distilled off to obtain a concentrate; vacuo (4) the hot concentrate was poured into a glass dish and placed in a dry 120 ~ 150 ℃ 5 ~ 12h dried under vacuum tank, i.e., to obtain a derivative of TDI-bis-carbamic acid alkyl esters gelling agents. Preparation of the gelling agent of the present invention can effectively gelling Russian oil spill into water, diesel, gasoline, soybean oil, peanut oil, cyclohexane, toluene, carbon tetrachloride, oil and other organic solvents, gelling agents added less rapidly solidified oil speed, high pour point oil cake strength, oil condensate thoroughly. | eng_Latn | 21,672 |
Interaction of NO2 gas with sublimed microporous layers of iron(II)-meso-mono-4-pyridyl-tri-aryl-porphyrins: Two different reaction pathways | Sublimed layers of FeIIMPyTPP and FeIIMPyTTP (MPyTPP and MPyTTP are meso-mono-4-pyridyl-triphenyl- and meso-mono-4-pyridyl-tri-p-tolyl-porphyrin dianions, respectively) consist of coordination oligomers that are formed by binding of pyridyl nitrogen atoms with the iron centers of the adjacent molecules in the film. Fourier transform infrared (FT-IR) spectroscopy including experiments with the 15NO2 isotopomer demonstrates that the reaction of low pressure NO2 gas with these layers leads to the formation of two types of complexes: six-coordinate nitro-complexes, in which the fifth site is occupied by the pyridyl group of the neighboring molecule in the layer and five-coordinate nitrito-complexes that terminate the oligomers. Further addition of NO2 increments leads to the preferential oxidation of these nitrito ligands to bidentate nitrato ligands. These layers conserve their porosity upon standing and allow study of the oxo-transfer reactivity from coordinated nitro-groups to appropriate oxygen acceptors. | Thispaperdescribesa polyimideinterlevelmetal coat U2 insulationprocess.The use of polyimidenear high voltagedevicescan resultin anomalousleakagein Goatel certainregionsat elevatedtemperatures.The paper Optional summarizesthe reliabilityinvestigation on discrete Plasma Nitride devicesfabricatedwith polyimide,as the interlevel material,as wellas characterization datawhichsupportdesigncriteriapermittingthe use of polyimide *F as an interlevelinsulation material. *s First Coat&Partial Cure Second Coat&Full Cure Excellent Planarization | eng_Latn | 21,673 |
Thermal degradation of styrene-methacrylic acid copolymers | Abstract Copolymers of styrene and methacrylic acid (MAA) with widely differing compositions have been studied by thermal volatilisation analysis (TVA) and thermogravimetry. The condensable volatile degradation products have been identified after separation by subambient TVA. The cold ring fraction (tar/wax products) and the structural changes in the residue in the course of degradation have also been examined. The copolymers are intermediate in stability between polystyrene (PS) and poly(methacrylic acid) (PMAA). The degradation products are mainly those expected by comparison with those obtained from the homopolymers, but methacrylic acid is formed in greater amount in the copolymer degradation and the distribution of MAA units leads to less intramolecular dehydration. Anhydride rings formed, however, reduce the zip length of depolymerisation to monomers, and both rings and isolated MAA units reduce the possibilities for transfer by polystyryl radicals. | In this report we introduce a new monolithic column for HPLC. The monolithic column was prepared using vinyl ester resin-co-ethylene dimethacrylate as the monomer. Using the free radical polymerization method a polymer network was formed, which was different from the traditional globular particles. The main factors affecting the porous structure of vinyl ester (VE) resin-based monolithic columns were investigated. By varying the porogen solvent, its content and the amount of initiator, different porous structures could be obtained. In order to evaluate the mechanical stability of the column material, the pressure drop across the column was measured at different flow-rates. Finally, using phenol, resorcinol and catechol as the test compounds, the normal-phase character of the poly(vinyl ester resin-co-ethylene dimethacrylate) monolith was evident. | eng_Latn | 21,674 |
Electrochemical properties of a liquid-crystalline mixed fullerene–ferrocene material and related species | The electrochemical properties of a fullerene–ferrocene liquid crystal are reported. The electrochemical study was carried out under strictly aprotic conditions: a total of seven reduction peaks were detected in the negative potential region, and two oxidation peaks in the positive potential one. Comparison of the data with those obtained from suitable model compounds (i.e., analogous fullerene- or ferrocene-free materials ) has allowed the assignment of all reduction and oxidation steps. The CV study evidenced the occurrence of a fast follow-up chemical reaction coupled to the third (at 25 °C) or fourth (at −60 °C) reduction of either 1 or 3. Such a reaction, presumably related to the cleavage of one of the cyclopropane bonds, is quantitatively reversed upon re-oxidation. Conversely, under bulk electrolysis conditions (second reduction), ::: the species undergo the retro-Bingel reaction, i.e. the irreversible removal of the bis(alkoxycarbonyl)methano adducts to give the parent C60. | The invention discloses a fluorine plastic and a fluorine plastic sleeve. The fluorine plastic is prepared from the following components in parts by weight: 100 parts of polytetrafluoroethylene dispersion resins, 3 to 15 parts of polyamide-imide resins and 20 to 25 parts of assistant oil. According to the fluorine plastic and the fluorine plastic sleeve, the low friction coefficient and the self-lubricating characteristic of the fluorine plastic are maintained to a maximum extent; and the defects of the fluorine plastic which is easy to creep and poor in abrasion resistance is overcome. Therefore, the fluorine plastic and the fluorine plastic sleeve have the best balance characteristic of self lubrication and abrasion resistance. | eng_Latn | 21,675 |
Diet-related DNA adduct formation in relation to carcinogenesis. | The human diet contributes significantly to the initiation and promotion of carcinogenesis. It has become clear that the human diet contains several groups of natural foodborne chemicals that are at least in part responsible for the genotoxic, mutagenic, and carcinogenic potential of certain foodstuffs. Electrophilic chemicals are prone to attack nucleophilic sites in DNA, resulting in the formation of altered nucleobases, also known as DNA adducts. Since DNA adduct formation is believed to signal the onset of chemically induced carcinogenesis, the DNA adduct-inducing potential of certain foodstuffs has been investigated to gain more insight into diet-related pathways of carcinogenesis. Many studies have investigated diet-related DNA adduct formation. This review summarizes work on known or suspected dietary carcinogens and the role of DNA adduct formation in hypothesized carcinogenesis pathways. | ABSTRACT Inorganic chemical gels obtained by hydrolysis/condensation of organic precursors (alcoxides) contain alcohol and water mixture which fills pores of the gel. This mixture is either removed in supercritical conditions or by convective drying. During convective drying gels significantly shrink producing porous glass-like xerogels. Adding a third component called DCCA (Drying Control Chemical Additive) to sol crates a diffusional barrier which lowers the drying rate and also reduces cracking. This Paper presents formulation and solution of a rigorous model of multicomponent diffusion both in liquid and gas phase in the case of convective drying of a gel cylinder containing a ternary mixture of ethanol. water and formamide as DCCA. Details of the numerical technique and methods used for prediction of physico-chemical property data involved in the solution of the model are presented. A short discussion of the obtained results follow. The model can provide a basis for a more complex process description... | eng_Latn | 21,676 |
Influence of microwave roast on the quality of aqueous extracted sesame oil | Using white sesame as raw material,the influence of microwave roast on the quality of aqueous extracted sesame oil was studied.The results showed that with the micromave roast temperature rising and time prolonging,the color of aqueous extracted sesame oil became deeper and appeared heavy red at last,with 70 of yellow value and 9.9 of red value(25.4 mm colorimetric groove);peroxide value increased at first,then declined;oxidate induction time extended gradually,and the longest oxidate induction time was 13.37 h;the change of acid value was not remarkable;the content of unsaturated fatty acids increased at first,then fell,and went up finally. | In this work the exact k_t data during the whole process of MMA bulk radical polymerization have been determined under unsteady state by using the post effect technique and ESR method. The effect of the micro-environment of radicals on the termination is discussed. | eng_Latn | 21,677 |
What is added to soap to make it clear? | How to make Transparent Soap Making Transparent Soap This is the result of my experiments making transparent soap. I am in no way, shape or form an expert, but I have successfully made transparent soap using recipes found on the web as well as formulating my own. I highly recommend reading the book "Making Transparent Soap" by Catherine Failor before you begin. This tutorial is not intended to replace the book, it is intended to complement the book. Transparent soap is basically partly soap and partly solvent. Sodium Hydroxide causes crystals to form in soap and that is why the soap becomes opaque, in order to make it transparent, you have to dissolve the soap in enough solvent to make the crystals so small that the the light will freely pass through the soap, which makes it look transparent. There is no magic number when it comes to the quantity of solvents required for a particular recipe, transparency will exist in a narrow window within a range. A good way to find the right quantity of solvents is to start by calculating a 60% soap/40% solvent ratio and then a 50% soap/50% solvent ratio, depending on your formula, transparency will exist somewhere in that range. (See the calculation page for tips on formulating your own recipes and to download a Transparent soap calculator to help you with the task. This tutorial is intended for people who already know how to make soap and are aware of the safety precautions that should be taken in order to do so. In this tutorial, we will use a very popular recipe by Jeff Bobeck . It is a good basic recipe and it works, it yielded my first successful batch of transparent soap, I modified it because I use 75.5% Alcohol instead of the 70% Alcohol used in the original recipe. Formulas can be adapted to use with the Alcohol you can find, although it would be difficult to go below 70% (140 Proof). Ideally, if you can find 190 Proof Alcohol, use it, it will make your life easier, if you can't, you can adapt a recipe to work with what you can find, just go to the calculation page to find out how. You need Ethanol (grain Alcohol) (Everclear) to make transparent soap, Isopropyl Alcohol will not work. I use a crock pot, I have gas appliances so I can't do it on the stove, using a slow cooker is an easy way to do it without the risk of setting the house on fire. First, print the recipe , assemble your supplies and clear 5 to 6 hours off your schedule. Preheat your oven to 180F (if it will go that low, if not, you will use the slow cooker to bring your soap to gel). Put a clear cup or glass in the freezer, you will need it to test the transparency of your soap. You will also need a wisk, lots of spoons, a spray bottle with alcohol in it, colorants (food colorants work, Select Shades are great), FO or your favorite perfume, a large pot with a spout, some Glad Press'n seal plastic wrap and a small plastic strainer. Measure your oils and heat them up in the slow cooker, I use a 4 quarts slow cooker, anything smaller would not work for this recipe, if you use a larger crock pot, you may have to tip it on its side somewhat so you can use your stick blender to mix the oils and the lye solution. Mix the lye with 6 oz of water and set aside to cool. When the oils and the lye are about 140F, pour the lye solution into the oils and stir with the stick blender, it should take only a few minutes to get to a good medium trace. At that point, put the cover on the soap and put it in a 180F oven for 1 1/2 hour. (If your oven won't go that low, just leave the soap in the slow cooker on warm and check it after an hour to see if it is going through the gel stage, I am not sure how long it will take for the soap to become neutral that way, but it should not take more than 2 hours. Try to minimize water loss because we already took a big water discount). After 1 1/2 hour, your soap should be neutral (PH of 9 - 10.5 is fine). The entire soap mass should be in the gel stage and look like somewhat like this: Stir it and test it either with phenolphthalein (if you have any) or litmus paper, if you don't | The dirtier I am, the whiter I get | Best Riddle Next Riddle Previous Riddle The dirtier I am, the whiter I get The dirtier I am, the whiter I get, Leave a mark on me when you stand, I'll leave a mark on you when you sit. What am I? Click to see the answer A chalkboard. | eng_Latn | 21,678 |
I have used eyesential for years, I'm getting really fed up with it looking flakey and scales. I Does genie to white and flakey ? | This product did not work at all. It was flaky and when I mixed with Moisturizer or concealer, it was sticky to the touch. I noticed no difference with this product at all. Sorry for the bad news. | Shore hardness is listed as "60 - 70" D. Here's the spec info from thier online store. TYPICAL PHYSICAL PROPERTIES (for liquid components) TEST METHOD COMPONENT 1 COMPONENT 2 Viscosity, cps ASTM D-2196 300 100 200100 Weight per gal, lbs. 8.2 8.6 Solids by weight, % ASTM D-1353 100 100 Mix ratio by weight 50 50 Mix ratio by volume 50 50 (for cured material) TEST METHOD RESULTS Density ASTM D-1622 75 - 80 lbs/ft (1.2 - 1.28 g/cc) Elongation, % ASTM D-2370 20 Shore D hardness 60 - 70 Shrinkage, linear inch unfilled 0.01 Color ivory to beige REACTIVITY DATA Gel time, seconds 180 20 Demold time, minutes 15 - 20 SHELF LIFE (STORAGE) *Component A (isocyanate) - storage area should be maintained between 65F to 85F. Containers must be tightly closed as a protection from moisture and foreign material. *Component B (polyol) - storage area should be maintained between 65F to 85F. Containers must be tightly closed as a protection from moisture and foreign material. | eng_Latn | 21,679 |
1986 film in which Bette Midler exclaims to Helen Slater, "I'm being marked down... I've been kidnapped by Kmart!" | 1000+ images about Sometimes Great Stuff Happens XIV on ... Don't write this movie off because it is impractical...great comedy. Save Learn more at ..... RUTHLESS PEOPLE New DVD Danny Devito Bette Midler. ebay.com. | Helene Curtis Industries Inc facts, information, pictures ... Helene Curtis Industries, Inc. manufactures and markets personal care ... In 1950 Helene Curtis developed the generic term hairspray for its new aerosol product, ... By the mid-1950s Helene Curtis products were being manufactured and sold in ... UniPerm became the first compact machine to give perfect permanent waves,... | eng_Latn | 21,680 |
Donna Summer was "Hot Stuff" in the summer of 1979, topping the charts with "Hot Stuff" & this naughty hit | She's a Rainbow: A Tribute to Donna Summer | PopMatters May 18, 2012 ... Have you dug beneath Summer's greatest hits and listened to .... the second of three consecutive chart-topping double albums, two number one pop ... She growled through the carnal heat of Hot Stuff but took All Through ... By 1979, she had racked up an impressive eight Top 5 pop hits in just four years. | Helene Curtis Industries Inc facts, information, pictures ... Helene Curtis Industries, Inc. manufactures and markets personal care ... In 1950 Helene Curtis developed the generic term hairspray for its new aerosol product, ... By the mid-1950s Helene Curtis products were being manufactured and sold in ... UniPerm became the first compact machine to give perfect permanent waves,... | eng_Latn | 21,681 |
In 1931, to produce this fiber, Wallace Carothers heated hexamethylene diamine & adipic acid | A Science Odyssey: People and Discoveries: Nylon is invented - PBS Wallace Carothers was 32 years old when he was appointed director of Du Pont Corporation's ... He published papers and obtained patents, and in 1931, Du Pont started to ... He combined the chemicals amine, hexamethylene diamine, and adipic acid. ... Carothers drew out fibers that were long, strong, and very elastic. | Dorothy Hamill's Famous Wedge Haircut Photo ... - Figure Skating Dorothy Hamill's Wedge Haircut From the 1970s - 1970s White Rain Hair Product ... the 1976 Olympic Ladies Figure Skating Champion, was known for her famous ... After she won the Olympics, Hamill endorsed many products, including White ... how and when her hair was cut just before the 1976 Olympic Winter Games:. | eng_Latn | 21,682 |
Method for applying formulations which contain bacteriorhodopsin onto substrates, and products produced by this method | The invention relates to a method for producing a coating in regions on the basis of a formulation which contains bacteriorhodopsin colour-changing pigment in the form of an active colour-change motif on a subtstrate, and to coatings which are produced using a method of this type and to articles having coatings of this type. Here, the method comprises the following steps: a) printing of the substrate, in the form of a motif, with the formulation which contains bacteriorhodopsin colour-changing pigment; b) partial drying of the printed substrate; c) optionally repetition of steps a) and/or b); d) calendering of the printed and partially dried substrate; e) complete drying of the coating. | Abstract A fluorescence microscopic technique was used to observe phase transitions in monolayers of DPPC. The sizes of the domain structures observed were found to be dependent on the rate of compression of the monolayer. The distribution of domain sizes for different rates of compression were unimodal, but the scatter in the sizes was greater during slow compressions. | eng_Latn | 21,683 |
Photoinitiated Polymerization-Induced Self-Assembly via Visible Light-Induced RAFT-Mediated Emulsion Polymerization | Aqueous emulsion polymerization is one of the most commonly used techniques in industry for the production of polymer latexes. In this contribution, we present photoinitiated polymerization-induced self-assembly (photo-PISA) based on aqueous visible light-induced reversible addition–fragmentation chain transfer (RAFT)-mediated emulsion polymerization at room temperature. A wide range of morphologies including spheres, worms, and vesicles have been achieved at room temperature by modulating reaction parameters. Additionally, this method enables access to inorganic nanoparticles-loaded vesicles by adding inorganic nanoparticles at the beginning of the polymerization. Finally, an oxygen-tolerant RAFT-mediated emulsion polymerization has been developed, allowing the synthesis of polymer nano-objects at low volumes (e.g., in a 96-well plate). This study is expected to expand the scope of photo-PISA for the preparation of various block copolymer nano-objects in water at room temperature. | Dynamic characteristic of a system have to be obtained so as to offer the reliable data for the system dynamic modification and dynamic optimum design. The system modal parameters identification can be changed into the global optimization problem in wavelet plane because the wavelet ridges can carry much information of system characteristic parameters. Firstly, the paper will introduce the so-called PSO (Particle Swarm Optimization) technique into the modal analysis and propose the PSO wavelet ridge extraction algorithm. Furthermore, the formulas identifying modal parameters from a wavelet ridge are derived and computation steps were given. The simulation experiments are implemented in order to evaluate precision of this method and the robustness of noise. Finally, the proposed method applies to the modal parameters identification of a watermelon to explore the effectiveness. The experiment results prove the method is precision and insensitive to noise. | eng_Latn | 21,684 |
Chemical methods for lignin depolymerization | (57) Abstract: The present invention claims the copper in an aqueous solution, a coordination compound, a method of depolymerization and / or modification of the peroxide lignin or lignin related compounds by the system. Copper coordination compound than 20% relative to the substrate in aqueous solution, is preferably applied in 0.001-5%. Coordination compounds, pyridine, histidyl-glycine, compounds containing phthalocyanine, acetonitrile, nitrogen, such as, compounds containing hydroxyl groups such as catechol, compounds such an ether like 18-crown-6, mercapto succinic acid compounds containing sulfur, such as, or compounds containing olefinic double bonds such as 1,3-cyclohexadiene. Peroxide hydrogen peroxide, organic peroxide, or to be added from outside as peracids, may also be produced in a solution containing lignin by reaction to produce a peroxide. | This paper presents an inferential property prediction scheme for a high pressure polyethylene autoclave reactor. The development of a dynamic model of the process is described. It was derived from a consideration of the reaction mechanism and uses reaction temperatures, pressure and gas composition to predict the degree of polymerisation of the polymer. The values of certain key parameters in the model were derived from steady state data from the ICI Alkathenc plant at Botany Site. The model was shown to predict the degree of polymerisation during grade transition with an appropriate accuracy although it benefited from an on-line adaption scheme. | eng_Latn | 21,685 |
Absorbent structure element for absorbent article | FIELD: technological processes. SUBSTANCE: there is provided absorbent structure element (13) for an absorbent article, comprising absorbent layer (17) with absorbent material (50) containing particles of a superabsorbent polymer and supported by supporting sheet (16), and having first and second substantially longitudinal channels (26), not containing said superabsorbent polymer particles and containing one or more adhesive materials for immobilizing said absorbent material (50). Channels can provide better fit of the product, and/or better reception and transport of liquids, and/or increased efficiency of the element as a whole. EFFECT: absorbent structure element for an absorbent article is provided. 16 cl, 18 dwg | Than the primer treatment with the treating composition to allow the aqueous ink composition of superior polymer-based, and generally discloses a production method thereof. More particularly, the polymer substrate may be a hydrophobic polymer substrate, such as those comprising a polyolefin, which exhibit excellent ink adhesion and frictional resistance than when the pre-treated with a treatment composition of the present invention. Polymer substrate, ink adhesion, polyolefin, friction resistance, print composition, the treating composition | eng_Latn | 21,686 |
Chitosan coating on freshness-preserving | The coating technology on Roselle was studied by using chitosan coating method.The results showed that the best formula is chitosan concentration of 1.5%,acetic acid concentration of 1.0%,1,2-propylene glycol concentration of 3.0%,Tween-20 concentration of 0.03%. | The analysis of power quality disturbances is the basis to improve the power quantity,and its key problem is how to accurately detect and position the occurrence time of the form of power mutation with noises.This paper proposes a signal processing algorithm that carries on the threshold filter and the correlation enhancement to high frequency data of wavelet transformation,then makes use of the mold biggest to detect saltation.This algorithm can not only well eliminate noise,but also validly strengthen the point of discontinuity information.It provides advantageous condition for following saltation detection.The simulation experiment result indicates that this algorithm has high precision and reliability in the strong noise jamming situation. This project is supported by National Natural Science Foundation of China(No.60402004). | eng_Latn | 21,687 |
Manufacturing process for vinyl ether | Production method of a vinyl ether polymer, said method comprising the step of polymerizing a vinyl ether monomer for obtaining a vinyl ether polymer; the vinyl ether monomer by using a polymerization initiator, a monovalent copper compound, a ligand which is coordinated to the copper compound, and ascorbic acid is subjected to a solvent in a living radical polymerization; the solvent is a weight ratio of isopropyl alcohol to water is from 30:70 to 0: 100 comprises; the weight ratio of the vinyl ether monomer to the solvent is from 10: 100;: 100-25 and the molar ratio of copper (I) in the copper compound to the ascorbic acid 1: 0.5 to 1: 2, wherein the polymerization initiator is an organic halide. | Abstract Ethylene dimerization has been studied by means of ab initio calculations using the STO-3G basis set. A transition state that presents a tricentric interaction has been found. The appearing of such structure is discussed and justified. | eng_Latn | 21,688 |
Preparation and Evaluation of Molecularly Imprinted Monolithic Column for Felodipine in Micro-liquid Chromatography | This study concentrated on the production of molecularly imprinted polymers (MIPs) as highly selective sorbents for felodipine (FLD), a representive dihydropyridine calcium antagonists.Demonstrated chromatographically through a selection factor, these MIPs showed high selectivity for the template molecule among a group of structurally similar compounds. The recognition was found to correlate with structural similarity to the template compound. | Abstract This work proposes a multi-period and spatially explicit framework conceived to drive strategic policies on biofuels. A Mixed Integer Linear Programming (MILP) model is proposed as quantitative tool to optimise the oncoming transition towards more sustainable infrastructures. This paper addresses the design of bioethanol supply chains where both corn grain and stover are considered as suitable biomass. A Mixed Integer Linear Program is proposed to optimise the system financial performance and to comply with EU environmental regulation by taking into account a wide number of technological options. Bioethanol production in Northern Italy is chosen as a demonstrative case study. | eng_Latn | 21,689 |
2 Chemistry and Characterization of Portland Cement | Publisher Summary This chapter deals with the physical and chemical properties, and the performance of the remarkable material, which are crucial to every facet of well cementing technology. The chapter reviews the manufacture, chemical composition, hydration chemistry, and classification of Portland cements. Well cementing exposes Portland cement to conditions far different from those anticipated by its inventor. Cement systems must be designed to be pumped under conditions ranging from below freezing in permafrost zones to greater than 1,000° F (538°C) in some thermal recovery wells. After placement, the cement systems preserve their integrity and provide zonal isolation during the life of the well. It is possible to accommodate such a wide range of conditions through the development of additives which modify the available Portland cements for individual well requirements. | Application of quartz crystal microbalance (QCM) sensors for odor sensing has been an important research topic. Proper performance of odor sensing systems with QCM sensors requires good discrimination among odor samples. Recently we have been studying pegylated lipopolymers - composed of lipid and poly(ethylene glycol). (PEG) The materials allowed for very good discrimination among odorants of different functional groups. Here we study lipopolymers with various molecular weight of PEG moiety. Our results indicate that the PEG chain length is an important factor influencing lipopolymer's sensing properties. | eng_Latn | 21,690 |
Tailoring the Composition and Properties of Sprayed CuSbS2 Thin Films by Using Polymeric Additives | CuSbS2 thin films were obtained by spray pyrolysis deposition, using polymeric additives for controlling the surface properties and film’s composition. Ternary crystalline chalcostibite compounds have been obtained without any postdeposition treatments. XRD spectra and IR spectroscopy were used to characterize films composition and interactions between components. Films morphology and surface energy were investigated using AFM microscopy and contact angle measurements. Hydrophobic and hydrophilic polymers strongly influence the composition and film morphology. | (57) Abstract: The present invention claims the copper in an aqueous solution, a coordination compound, a method of depolymerization and / or modification of the peroxide lignin or lignin related compounds by the system. Copper coordination compound than 20% relative to the substrate in aqueous solution, is preferably applied in 0.001-5%. Coordination compounds, pyridine, histidyl-glycine, compounds containing phthalocyanine, acetonitrile, nitrogen, such as, compounds containing hydroxyl groups such as catechol, compounds such an ether like 18-crown-6, mercapto succinic acid compounds containing sulfur, such as, or compounds containing olefinic double bonds such as 1,3-cyclohexadiene. Peroxide hydrogen peroxide, organic peroxide, or to be added from outside as peracids, may also be produced in a solution containing lignin by reaction to produce a peroxide. | eng_Latn | 21,691 |
Synthesis of benzoporphyrins with one or two meso-substitutents via substitution reactions | Reaction of either free base benzoporphyrin, its zinc(II) complex or β-bicyclo(2,2,2)octeno appended precursor porphyrins with LiR reagents gave an entry into mono- and soluble di-meso-substituted benzoporphyrins. | The invention relates to a method for producing a coating in regions on the basis of a formulation which contains bacteriorhodopsin colour-changing pigment in the form of an active colour-change motif on a subtstrate, and to coatings which are produced using a method of this type and to articles having coatings of this type. Here, the method comprises the following steps: a) printing of the substrate, in the form of a motif, with the formulation which contains bacteriorhodopsin colour-changing pigment; b) partial drying of the printed substrate; c) optionally repetition of steps a) and/or b); d) calendering of the printed and partially dried substrate; e) complete drying of the coating. | eng_Latn | 21,692 |
Highly catalytic activity of platinum-gold particles modified poly(p-aminophenol) electrode for oxygen reduction reaction | A highly active electrocatalyst has been developed based on poly(p-aminophenol) polymer film modified with Pt-Au bimetallic particles on a glassy carbon electrode (Pt-Au/PPAP/GCE) for electrocatalytic reduction of oxygen. The surface morphology and chemical analyses of the modified electrodes have been revealed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and electrochemical impedance spectroscopy (EIS). The Pt-Au/PPAP/GCE has shown the best electrocatalytic activity towards O2 reduction in comparison to the other used electrodes. The rotating disk electrode (RDE) studies have indicated that the oxygen reduction reaction takes place via almost four electrons on the Pt-Au/PPAP/GCE. | The combination of alkali chemical pulping and alu-minum oxide was introduced in this paper.In the process of alkli recovery system, the burning stage was cancelled, the black liquor with proper concentration was directly pumped into a aluminum dioxide plant as a material for smelting of alumi-num to recover alkali and heat through calcining and causticization process.The technological principle and the pro-cess of combining production were explored and elaborated in experiment.The results showed that the technique of combin-ing production was feasible and the environmental and eco-nomic benefits were remarkable.The new technique not only provides an alternate way for the blach liquor treatment, but also reduces the production cost of both paper and aluminum oxide.A clean technical project was constructed with regional recycling economic characteristics of combining chemical pulping with aluminum oxide. | eng_Latn | 21,693 |
Compaction and Monolith Production of Ultrahigh-Molecular-Weight Polyethylene Reactor Powders | Morphological changes of ultrahigh-molecular-weight polyethylene reactor powders were studied using scanning electron microscopy after their compaction and monolith production. The optimum conditions (pressure and temperature) for the compaction and monolith production of the reactor powders were determined. | A mathematical model describing the behavior of elution peaks in preparative liquid chromatography for multicomponent separation has been solved numerically with the application of the perturbation and modified collocation methods. With application of such a collocation method on the time and axial domains, the governing equations are transformed into a set of recursive, algebraic equations that can be solved efficiently. The simulation results excellently match the reported experimental elution profiles resulting from the separation of a binary mixture of dipeptides on a reversed phase column in the literature. The results from the binary system can be extrapolated to multicomponent separation. For a given system of stationary and mobile phases, the model simulation predicts that the sample volume, concentrations of solutes in the sample, flow velocity, and particle diameter influence the performance of the elution peaks considerably. When samples having a given composition are chromatographied on a prep... | eng_Latn | 21,694 |
Living radical network polymerization: Alkoxyamine-mediated copolymerization of dimethacrylates with styrene | The kinetics of network copolymerization of styrene with dimethacrylates in the presence of alkoxyamines as initiators of living radical polymerization (iniferters) was studied. Conclusive evidence that the copolymerization proceeds in the living chain mode was obtained with the techniques of precision isothermal calorimetry, ESR, and rheokinetics. This conclusion is based on the dramatic shift of the conversion corresponding to the formation of a continuous polymer network to the region of high degrees of polymerization (>10%) as compared to the conventional network polymerization (<1%), as well as on the high concentrations of a nitroxide radical, the inhibitor, during the polymerization process at simultaneously retained fairly high reaction rates. | The present invention relates to a biomass material containing xylose / arabinose hydrolysis of the polymers in the present method. The hydrolysis is carried out by an acid salt produced is present in the matrix, whereby the acid is continuously recycled, thereby significantly reducing emission of salt. | eng_Latn | 21,695 |
Polymeric fluorescent brighteners | Polymeric fluorescent brighteners (PFBs) which are polymerized by fluorescent monomer and other monomers can solve poor photostability of traditional FBs.Classification of the PFBs is briefly introduced.The synthesis, structure, properties and application of stilbene, naphthalimide and pyrene FBs are discussed. The basic structure of chromogen in PFBs remains the same,so PFBs have fluorescent properties of traditional FBs.Covalent bonds between chromogen and macromolecule chains enhance their photochemical stability,increase their whitening performance and fluorescence quantum yield. PFBs can be used not only for textile, polymeric materials and detergents,but also for high technology fields,such as liquid crystal displays,fluorescent probes, etc.Developing environmentally friendly high performance new products, mixing different PFBs and polymerizing more monomers with different chromogens are likely to be new areas of research. | Abstract A micropolar fluid, which is characterized by the presence of suspended rigid particles with microstructure, can be used as a model for lubricants containing suspended additive particles. The theory is applied to the study of the lubrication of an inclined stepped composite bearing with an additive-containing lubricant. The theory yields results showing an increase in the load-carrying capacity and a reduction in the coefficient of friction which are in agreement with experimental observations. | eng_Latn | 21,696 |
Monomer release from nanohybrid composites after bleaching. | The evaluation of the effect of bleaching on monomer release from two composite resins was performed by bleaching two nanohybrid composite resins Filtek Z550 and Tetric N-Ceram using two bleaching products Whiteness HP Maxx and Vivastyle. In total, 20 samples were made from each composite resin from which four groups were fabricated (two for each bleaching product). The samples were stored in a 75% ethanol solution, and the solutions were renewed after 1, 7, and 28 days. The monomer release was analyzed using high performance liquid chromatography. The data were analyzed using repeated measures analysis of variance and least significant difference multiple comparison test (α = 0.05). Monomers were found to be released from both composite resins. The amounts of monomer released were found to decrease over time (P < 0.05); however, the resins were not affected by bleaching, and the released monomers were well below toxic doses. | Microechography was used to characterize crosslinking gradients in photopolymers, because this technique can produce acoustic images of amplitude variations of local mechanical properties. A frequency of 25 MHz was chosen due to the high absorption of the investigated material at high frequencies. Two sets of samples were studied. The former, which had been polymerized through a test mask and displayed sharp gradients, were used to check the sensitivity of the technique; the latter were insulated through a chromium apodizing filter with a radial density variation and allowed the resolution of the apparatus to be determined. Results obtained on the exposed sample surfaces and on cross sections showed that this technique is well suited to the study of crosslinking gradients in, photopolymers despite the resolution loss resulting from the use of low frequencies. The method is exemplified by the study of mask pattern transfer into a polymer. | eng_Latn | 21,697 |
Relationship between curing activation energy and free formaldehyde content in urea-formaldehyde resins | This study investigated the effect on the curing behavior, activation energy (E a) of the curing reaction, crystalline structure, crosslinking, and free formaldehyde content of the addition of the following scavengers in urea-formaldehyde (UF) resins: medium density fiber board flour, rice husk flour, silica powder, and tannin powder. The scavenger content was 3 and 7 wt% of the UF resin solid content. The curing behavior of UF resins was monitored by differential scanning calorimetry, thermogravimetric analysis, and X-ray crystallography. The curing E a was correlated to the free formaldehyde content of the scavenger containing UF resins. The thermal stability of the UF resins increased but the curing E a decreased with increasing scavenger content. After curing, the crystallinity of the UF resins decreased in the presence of scavengers. The unreacted free formaldehyde content was reduced in the tannin powder containing UF resins. The degree of crosslinking affects the formaldehyde emission from wood pan... | Abstract The capability of Auger transition probabilities experimentally derived from X-ray excited Auger electron spectra in XPS were tested. The relative sensitivity factor (RSF) method has been employed in the quantification by AES (Electron excited Auger electron spectroscopy). However, the difference between experimentally derived RSF and theoretically calculated ones has been found in some reports. One of the great reason of the difference may be caused by the calculated values of the Auger transition yield which has been commonly employed without the consideration of the allotment of coupling scheme in the transition selected in the quantification, for instance, the allotment of each six coupling KL 1 L 1 , KL 1 L 2 , KL 1 L 3 , KL 2 L 2 , KL 2 L 3 , and KL 3 L 3 in KLL transition. The employment of derived Auger transition probabilities reduce the difference between theoretically calculated RSF and experimentally derived one. | eng_Latn | 21,698 |
Heterogeneity in Mixed Cerium Oxides and Its Influence on the Behavior of Gold Catalysts for the Selective Oxidation of Ethanol | Mixed metal oxides have been investigated for a host of applications, yet many questions regarding the relationship between their material properties and their functional behavior remain unanswered. Mixed metal oxides are frequently used as support materials for catalytic processes, and the structure/composition of the oxide can significantly influence the behavior of a mixed oxide supported catalyst. In this article, we study the material properties of binary mixed cerium oxide supports synthesized with various metal additives and their corresponding influences on the behavior of gold catalysts for selective oxidation of ethanol. We have found that, although all of these materials exhibited X-ray diffraction patterns consistent with a pure cerium oxide phase, compositional heterogeneities were present in many of the samples, as indicated by time-of-flight secondary ion mass spectrometry and temperature-programmed-reduction techniques. Furthermore, the mixed cerium oxide supported gold catalysts demonstra... | This paper introduces the theories of cationic modification of linen and puts forward the optimal process conditions of cationic modification and dyeing of linen through orthogonal experiment and analysis. By comparing and analyzing the dyeing samples of the cationised linen and non-cationised linen, it also shows that cationic modification has clear effect to enhance the dyeing capability of rhubarb on linen. | eng_Latn | 21,699 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.