bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the engineering properties of LCP‐Vectra B 950/PP blends with the variations of EAA content
Authors: Mandal Pijush K. , Siddhanta Samir K. , Chakraborty Debabrata 
Published: October 2010

AbstractPolypropylene (PP) was melt blended with Vectra B‐950 [a thermotropic liquid crystalline polymer (LCP)], in a single screw extruder in presence of different doses of ethylene acrylic acid (EAA) copolymer, as modifier. The effect of incorporation in different proportions of EAA at a fixed dose of 5% LCP, on mechanical, thermal, morphological, and rheological properties of such blends was studied and the same were compared with that of pure PP and amongst themselves. Mechanical analysis (tensile properties) of the prepared blends exhibited improvements in ultimate tensile strength (UTS), modulus, toughness, hardness, and impact strength of PP matrix with the incorporation of EAA. The improvement in mechanical properties is associated with the formation of LCP fibrils as evidenced by scanning electron microscopy (SEM). A strong interaction through H‐bonding between the segments of Vectra B‐950 and EAA was established by FTIR study. Differential scanning calorimetry (DSC) studies indicated substantial increase in melting point of the blends, and thermogravimetric analysis (TGA) showed that the thermal stability of PP was improved with the addition of LCP and EAA. Rheological properties showed that LCP and EAA drop down the melt viscosity of PP and thus facilitate processibility of blends. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation of some dielectric greases from different types of polymers
Authors: Hassan A. M. , Shahba R. M. A. , Youssif M. A. , Mazrouaa A. M. , Youssif M. A. E. 
Published: October 2010

AbstractAt this research the grease (S0) containing [base lube oil grade 260/290, transformer oil, microcrystalline wax, Polyoxyethylene sorbiton‐mono‐palmitate antioxidant 2,2″methylenebis(4‐methyl‐6‐tertiary‐butyl phenol) anticorrosion] was prepared. To improve its physicochemical & dielectric properties (dielectric constant, dielectric loss, and volume resistivity) and giving it a good electrical insulator property, we add to the wax gel a nonpolar polymer as polyethylene, atactic polypropylene, unplastesized polyvinyl chloride, and plasticized polyvinyl chloride include triisopropyle vinyl phosphate in certain concentration. We conclude that the best insulation properties was achevied by adding atactic polypropyle. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Electropolymerization of highly hydrophobic polythiophene films with high adhesion force
Authors: Yu Weili , Yao Tongjie , Li Xiao , Wang Tieqiang , Gao Hainan , Zhang Junhu , Yang Bai 
Published: October 2010

AbstractElectrochemical cyclic voltammetry (C‐V) method was reported to prepare highly hydrophobic polythiophene (PTh) films with high adhesion force. Using this technique, the morphology and surface roughness of PTh film can be controlled by adjusting cycle number, monomer concentration, and applied voltage. After fluorination, the PTh film with hierarchical morphology showed high hydrophobicity as well as a strong adhesion force. This method provides a simple solution for the preparation of highly hydrophobic polymer film with high adhesion force. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Cytotoxicity and cellular uptake evaluation of mitoxantrone‐loaded poly(lactic acid‐co‐lysine) arginine–glycine–aspartic acid nanoparticles
Authors: Qi Xuelian , Chen Xiaoyan , Sun Ying , Ma Zhichao , Guo Xiaojuan , Lu Wei , Duan Yourong 
Published: October 2010

AbstractThe purpose of this study was to evaluate the in vitro characteristics of poly(lactic acid‐co‐lysine) arginine–glycine–aspartic acid (PLA–PLL–RGD) nanoparticles (NPs) loaded with mitoxantrone. PLA–PLL–RGD NPs with a particle size of 200 nm were prepared with a modified emulsification solvent‐diffusion method. The encapsulation efficiency of the mitoxantrone‐loaded NPs was 85%. In vitro release experiments showed that the release of the drug was prolonged and sustained, and approximately 60.2% of the mitoxantrone was released in the first week. The released drug was integrated to achieve desired drug‐release profiles and still possessed bioactivity according to a 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2h‐tetrazolium bromide assay, which indicated that mitoxantrone‐loaded NPs were more cytotoxic against Michigan Cancer Foundation 7 (MCF‐7) breast cancer cells than mitoxantrone. Furthermore, the association processes of NPs with MCF‐7 cells, including binding and effective internalization, were investigated in vitro. The cellular uptake of the NPs was qualitatively studied with confocal laser scanning microscopy and was confirmed with flow cytometry analysis. These experimental results indicated that PLA–PLL–RGD NPs could be used as drug carriers for mitoxantrone. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Blocked isocyanates and isocyanated soybean oil as new chain extenders for unsaturated polyesters
Authors: Taylan E. , Küsefoğlu S. H. 
Published: October 2010

AbstractTwo different blocked isocyanates, diphenylmethane–bis‐4,4′‐ethyleneurea and diphenylmethane–bis‐4,4′‐carbamoil–ϵ‐caprolactam, and isocyanated soybean oil were used as chain extenders for low‐molecular‐weight unsaturated polyesters. Oligomeric polyesters (molecular weight = 600–700), taken from a manufacturing process in the sixth hour of a 16‐h polyesterification reaction, were reacted with these chain extenders, and the desired chain lengths (molecular weight = 1000–1500) were obtained in a very short time through the reaction of the chain extenders with the polyester end groups. The increase in the molecular weight was monitored with gel permeation chromatography. The obtained polymers were characterized with Fourier transform infrared and 1H‐NMR and with styrene solubility and gel time measurements. After dilution with styrene, the polyesters were cured with a radical initiator. The thermal and mechanical properties of the cured polyesters were examined with dynamic mechanical analysis and thermogravimetric analysis tests and then compared to those of a commercially available reference unsaturated polyester. The results show that unsaturated polyesters can be chain‐extended with these compounds to shorten the polyesterification time substantially without alterations of the styrene solubility or gel time of the polyesters. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis and applications of polyacrylamide gels catalyzed by silver nitrate
Authors: Singh Ajit 
Published: October 2010

AbstractPolyacrylamide gels are widely used as matrices for biomolecular analysis and fractionation, and they are being developed as biomaterials for diverse medical and industrial applications. This study reports silver nitrate as a novel catalyst for the synthesis of polyacrylamide gels from acrylamide and N,N‐methylene bisacrylamide monomers. The conditions were defined for silver‐catalyzed, free‐radical‐induced polymerization, and a suitable buffer system was devised for the electrophoretic resolution of nucleic acids. A silver‐staining procedure was modified for these gels, and they were compared with N,N,N′,N′‐tetramethylethylenediamine‐catalyzed gels for sensitivity and gel background. Silver nitrate and ammonium persulfate at final concentrations of 100 and 625 μg/mL, respectively, polymerized the resolving gels within 20 min at room temperature. These gels exhibited antimicrobial properties. The gels with ≥10 μg/mL silver nitrate showed a zone of complete inhibition of Staphylococcus aureus growth on a Luria–Bertani agar plate. The silver‐catalyzed gels were also suitable as antigen‐ and drug‐delivery devices. Silver, acting as both a catalyst and a microbicidal agent, was better than N,N,N′,N′‐tetramethylethylenediamine for the synthesis of polyacrylamide gels as drug‐ and oxygen‐delivery devices for topical applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Transparent polysilicone coatings as protecting films for gold commemorative coins
Authors: Liu Yan , Yan Guo‐Ping , Che Hong‐Wei , Wang Xiao‐Yan , Guo Qing‐Zhong 
Published: October 2010

AbstractNovel transparent organic silicone resin coatings were successfully prepared through the reaction between the alkoxy groups of methyltrimethoxy‐silane (MTMS) and γ‐aminopropyltriethoxysilane (APTES) and hydroxyl groups of hydroxyl terminated silicone oil (HTSO). The influences of different monomer feed mass ratio on the coating properties were investigated via measuring the hydrophobicity and hardness of coating films. The coating films were characterized with IR, UV, TG, scanning electron microscope (SEM), and automatic contact angle meter. Some properties of coating films, such as adhesion, impact resistance, and wear‐resistance, were also evaluated. The results indicated that these coating films formed on the surfaces of gold commemorative coins possessed some good properties including high hydrophobicity, high water contact angles, high light transmittance, good heat‐resistance, adhesion, hardness, and weatherability, etc. Moreover, the uniform, clear, transparent, and dense coating films did not cover the symphony surface patterns or affect the metallic luster. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Influence of 1,2 units content on the hydrogenation of polydienes by TSH
Authors: Santin C. K. , Jacobi M. M. , Schuster R. H. 
Published: October 2010

AbstractThe influence of 1,2 vinyl content on hydrogenation of SBR and BR rubbers with high molecular weight by a noncatalytic method using p‐toluenesulfonylhydrazide (TSH) as reagent was investigated. Results show an increase of hydrogenation percentage with molar ratio of the reagents, temperature, and reaction time. The degree of hydrogenation depends strongly on the microstructure of the rubber mainly on the amount of 1,2 content. Infrared spectroscopy (FTIR) was used to confirm the microstructural characteristics of the hydrogenated rubbers. The degree of hydrogenation was determined by iodometry method and 1H‐NMR analysis. The change in the thermal behavior of hydrogenated rubbers was followed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), which showed a difference in flexibility chain and thermal stability. The kinetic studies demonstrate that the diimide reduction follows a first‐order reaction with respect to olefin substrate. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Construction of nonpathological Lyapunov functions for discontinuous systems with Caratheodory solutions
Authors: Armaki Alireza Faraji , Pariz Naser , Asgharian Rajab 
Published: October 2010

AbstractThis paper presents a method based on the Nonpathological Lyapunov theorem for constructing Lyapunov function (LF) for discontinuous time invariant dynamical systems with Caratheodory solutions. The origin is stable, if the method constructs a Nonpathological Lyapunov Function (NPLF) for the system.Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Practical adaptive iterative learning control framework based on robust adaptive approach
Authors: Chen Weisheng , Li Junmin , Li Jing 
Published: October 2010

AbstractThis paper addresses a unified framework for a practical iterative learning control from a robust adaptive control viewpoint. It shows that if a Lyapunov method based on robust adaptive control scheme is available, and the Lyapunov function satisfies certain conditions, then it is straightforward to extend the robust adaptive controller to handle the practical iterative learning control problem in the system under consideration. Two examples are provided to show the application of the design method. The corresponding simulation results are given to verify the effectiveness of the control algorithm proposed in this paper.Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Necessary and sufficient stability condition of LTV iterative learning control systems using a 2‐D approach
Authors: Meng Deyuan , Jia Yingmin , Du Junping , Yu Fashan 
Published: October 2010

AbstractThis paper deals with the stability analysis of discrete iterative learning control (ILC) by developing a two‐dimensional (2‐D) approach under the Roesser systems framework. The system under consideration is a class of multiple‐input multiple‐output (MIMO), linear time‐varying (LTV) systems. Using a type of two‐gain ILC, it is shown that once the theory is established for the discrete‐time‐varying 2‐D Roesser systems, a necessary and sufficient condition for the stability of ILC process can be determined directly. Numerical simulation is included to verify the theoretical results.Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Impact of revised and potential future albedo estimates on CCSM3 simulations of growing‐season surface temperature fields for North America
Authors: Heilman Warren E. , Hollinger David Y. , Li Xiuping , Bian Xindi , Zhong Shiyuan 
Published: October 2010

AbstractRecently published albedo research has resulted in improved growing‐season albedo estimates for forest and grassland vegetation. The impact of these improved estimates on the ability of climate models to simulate growing‐season surface temperature patterns is unknown. We have developed a set of current‐climate surface temperature scenarios for North America using the Community Climate System Model—Version 3 (CCSM3). Simulation results suggest that modifications to the default CCSM3 radiative parameters that are consistent with more recent accurate measurements of albedo values for grasslands and needle‐leaf deciduous trees (NDTs) can reduce the overall growing‐season surface temperature bias over North America in CCSM3 simulations. Copyright © 2010 Royal Meteorological Society
Sol–gel synthesis, characterization and luminescence properties of SrMgAl2SiO7:Eu2+ as a novel nanocrystalline phosphor
Authors: Salimi R. , Sameie H. , Sabbagh Alvani A. A. , Sarabi A. A. , Moztarzadeh F. , Tahriri M. 
Published: October 2010

ABSTRACTIn this research, a new SrMgAl2SiO7:Eu2+ phosphor was synthesized via the sol–gel method. The phase‐forming processes were studied by thermogravimetric–differential thermal analysis and X‐ray diffraction technique. Scanning electron microscopy showed that there is uniform morphology and microstructure owing to the sol–gel route. Spectrophotometry and colorimetry analyses illustrated that, under short ultraviolet excitation, the main emission peak occurred at 421 nm and also a relatively pure blue color was observed that was ascribed to the 4f65d1(2D) → 4f7(8S7/2) transition of Eu2+ with color coordination of x = 0.187, y = 0.077. Finally, it was found that the color and phase purity of the synthesized powder increased as calcinations time increased. Copyright © 2010 John Wiley & Sons, Ltd.
Biosurfactant production and growth kinetics of bacteria in a designer marine medium: Improved physiochemical properties
Authors: Sivapathasekaran C. , Mukherjee Soumen , Sen Ramkrishna 
Published: October 2010

AbstractA combinatorial screening strategy was adopted for the development of a suitable medium for enhanced biosurfactant production by a marine strain. As a result, a modified marine medium (MMM) was developed, which contained urea and strontium chloride besides other salts important for the growth of marine bacteria. This medium supported growth, evident from a higher maximum growth rate value of 0.42 h–1 and an enhanced biosurfactant production of 2.58 g/L. The critical micelle concentration (CMC) was determined for the biosurfactants obtained from all tested media combinations. The biosurfactant produced with this medium was stable at high temperature (100°C), a wide range of pH (5–11) and salt concentration of 5–35%. The emulsifying activity and stability of the biosurfactant obtained using MMM was better than the biosurfactant obtained using conventional media. This biosurfactant with improved physiochemical properties is suitable for a wide range of applications in industry and for marine environmental cleaning.
Enhanced cell viability and cell adhesion using low conductivity medium for negative dielectrophoretic cell patterning
Authors: Puttaswamy Srinivasu Valagerahally , Sivashankar Shilpa , Chen Rong‐Jhe , Chin Chung‐Kuang , Chang Hwan‐You , Liu Cheng Hsien 
Published: October 2010

AbstractNegative dielectrophoretic (n‐DEP) cell manipulation is an efficient way to pattern human liver cells on micro‐electrode arrays. Maintaining cell viability is an important objective for this approach. This study investigates the effect of low conductivity medium and the optimally designed microchip on cell viability and cell adhesion. To explore the influence of conductivity on cell viability and cell adhesion, we have used earlier reported dielectrophoresis (DEP) buffer with a conductivity of 10.2 mS/m and three formulated media with conductivity of 9.02 (M1), 8.14 (M2), 9.55 (M3) mS/m. The earlier reported isotonic sucrose/dextrose buffer (DEP buffer) used for DEP manipulation has the drawback of poor cell adhesion and cell viability. A microchip prototype with well‐defined positioning of titanium electrode arrays was designed and fabricated on a glass substrate. The gap between the radial electrodes was accurately determined to achieve good cell patterning performance. Parameters such as dimension of positioning electrode, amplitude, and frequency of voltage signal were investigated to optimize the performance of the microchip.
Metabolism of green tea catechins by the human small intestine
Authors: Schantz Markus , Erk Thomas , Richling Elke 
Published: October 2010

AbstractNumerous studies have shown that green tea polyphenols can be degraded in the colon, and there is abundant knowledge about the metabolites of these substances that appear in urine and plasma after green tea ingestion. However, there is very little information on the extent and nature of intestinal degradation of green tea catechins in humans. Therefore, the aim of this study was to examine in detail the microbial metabolism and chemical stability of these polyphenols in the small intestine using a well‐established ex vivo model. For this purpose, fresh ileostomy fluids from two probands were incubated for 24 h under anaerobic conditions with (+)‐catechin (C), (‐)‐epicatechin (EC), (‐)‐epicatechin 3‐O‐gallate (ECG), (‐)‐epigallocatechin (EGC), (‐)‐epigallocatchin 3‐O‐gallate (EGCG) and gallic acid (GA). After lyophilisation and extraction, metabolites were separated, identified and quantified by high performance liquid chromatography‐photodiode array detection (HPLC‐DAD) and HPLC‐ESI‐tandem mass spectrometry. Two metabolites of EC and C (3', 4', 5'‐trihydroxyphenyl‐γ‐valerolactone and 3', 4'‐dihydroxyphenyl‐γ‐valerolactone) were identified. In addition, 3', 4', 5'‐trihydroxyphenyl‐γ‐valerolactone was detected as a metabolite of EGC, and (after 24‐h incubation) pyrogallol as a degradation product of GA. Cleavage of the GA esters of EGCG and ECG was also observed, with variations dependent on the sources (probands) of the ileal fluids, which differed substantially microbiotically. The results provide new information about the degradation of green tea catechins in the gastrointestinal tract, notably that microbiota‐dependent liberation of GA esters may occur before these compounds reach the colon.
Apolipoprotein A‐IMilano anion exchange chromatography: Self association and adsorption equilibrium
Authors: Bankston Theresa E. , Carta Giorgio 
Published: October 2010

AbstractThe self‐associative properties of apolipoprotein A‐IMilano (apoA‐IM) were investigated in relationship to its anion exchange behavior on Q‐Sepharose‐HP with and without the addition of urea as a denaturant. Self‐association was dependent on protein and urea concentration and both influenced interactions of the protein with the chromatographic surface. In the absence of urea, apoA‐IM was highly associated and existed primarily as a mixture of homodimer, tetramer and hexamer forms. Under these conditions, since the binding strength was greater for the oligomer forms, broad, asymmetrical peaks were obtained in both isocratic and gradient elution. Adding urea depressed self‐association and caused unfolding. This resulted in sharper peaks but also decreased the binding strength. Thus, under these conditions chromatographic elution occurred at lower salt concentrations. The adsorption isotherms obtained at high protein loadings were also influenced by self‐association and by the varying binding strength of the differently associated and unfolded forms. The isotherms were thus dependent on protein, urea, and salt concentration. Maximum binding capacity was obtained in the absence of urea, where adsorption of oligomers was shown to be dominant. Adding urea reduced the apparent binding capacity and weakened the apparent binding strength. A steric mass action model accounting for competitive binding of the multiple associated forms was used to successfully describe the equilibrium binding behavior using parameters determined from isocratic elution and isotherm experiments.
Gender and physical punishment: the filipino children's experience
Authors: Sanapo Margaret S. , Nakamura Yasuhide 
Published: October 2010

AbstractThis paper reports selected findings from a doctoral dissertation on Filipino children's attitudes towards physical punishment. The findings of this research stem from a survey of 270 grade‐six students in Iloilo, Philippines. The results indicated that the majority (61.1%) had experienced physical punishment at home. The most common punishment children received was pinching (74.5%), followed by beatings (49.7%). The chi‐square analysis revealed that more boys than girls were physically punished (p < 0.05). Mothers were found to be the most frequent users of physical punishment. The prevalence of physical punishment at home may be attributed to Philippine law which ‘allows parents to physically punish their children as may be necessary for the formation of his good character’ as reflected in Article 45 of Presidential Decree No. 603, known as ‘The Child and Youth Welfare Code’ (Article 45, PD 603). The tendency of Filipino parents to punish sons more harshly than their daughters could be explained in relation to how boys and girls are regarded in society. Boys are expected to be tough and brave. By administering harsher discipline, parents may believe they are moulding their sons to be strong and to prepare them to be future pillars of society. Copyright © 2010 John Wiley & Sons, Ltd.
On the Mechanism of Ruthenium‐Catalyzed Formation of Hydrogen from Alcohols: A DFT Study
Authors: Johansson Adam Johannes , Zuidema Erik , Bolm Carsten 
Published: October 2010

AbstractThe mechanism of the ruthenium‐catalyzed dehydrogenation of methanol has been investigated by using three DFT‐based methods. Three pathways were considered in which the ruthenium catalyst was ligated by either two or three phosphine ligands. Dispersion interactions, which are not described by the popular B3LYP functional, were taken into account by using the dispersion‐corrected B3LYP‐D and M06 density functionals. These interactions were found to be important in the description of reaction steps that involved ligand/substrate/product association with or dissociation from the catalyst. In line with experimental results, the resting state of the catalyst was predicted to be a ruthenium trihydride complex. It is shown that the dehydrogenation reaction preferentially proceeds through pathways in which the catalyst is ligated by two phosphine ligands. The catalytic cycle of the dehydrogenation process involves an intermolecular proton transfer from the methanol substrate to the catalyst followed by the release of dihydrogen. Rate‐determining β‐hydride elimination from the resulting methoxide species then regenerates the resting state of the catalyst and completes the catalytic cycle. The overall free‐energy barriers of 29.6–31.4 kcal mol−1 predicted by the three density functionals are in good agreement with the experimentally observed reaction rate of 6 h−1 at 423 K.