bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and characterization of quaternary ammonium ionomers
Authors: Pazhanisamy P. , Ariff Mohamed , Anwaruddin Q. 
Published: August 2005

AbstractThe cationic monomers, MPDMAC16and MPDMAC18, were obtained by quaternization of methacrylamidopropyl–N,N′‐dimethylamine withn‐alkyl iodides (1‐iodohexadecane and 1‐iodooctadecane) in ethyl acetate. Hydrophobic ionomers of MPDMAC16and MPDMAC18with N‐substituted acrylamides were prepared at 60 ± 0.1°C in DMF using AIBN initiator. The cationic monomers and ionomers were characterized by1H‐ and13C‐NMR spectroscopy. The copolymer composition was evaluated from elemental analysis data using carbon/nitrogen (C/N) ratio. The molecular weight distributions of ionomers were obtained from GPC analysis. Both the dilute solution and concentrated solution properties of ionomers were studied by viscometry at 30°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1100–1105, 2005
Effects of preparation method on microstructure and properties of UV‐curable nanocomposite coatings containing silica
Authors: Li Fusheng , Zhou Shuxue , Wu Limin 
Published: August 2005

AbstractUV‐curable nanocomposites were prepared by the blending method or the in situ method with nanosilica obtained from a sol–gel process. The microstructure and properties of the nanocomposite coatings were investigated using 29Si‐NMR cross‐polarization/magic‐angle spinning, transmission electron microscopy (TEM), Fourier transform IR (FTIR), differential scanning calorimetry (DSC), and UV–visible (UV–vis) spectra, respectively. The NMR and TEM showed that during the blending method, tetraethyl orthosilicate (TEOS) completely hydrolyzed to form nanosilica particles, which were evenly dispersed in the polymer matrix. However, for the in situ method, TEOS partially hydrolyzed to form some kind of microstructure and morphology of inorganic phases intertwisted with organic molecules. FTIR analysis indicated that the nanocomposites prepared from the in situ method had much higher curing rates than those from the blending method. DSC and UV–vis measurements showed that the blending method caused higher glass‐transition temperatures and UV absorbance than the in situ method. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1119–1124, 2005
Electrical properties and morphology of polypropylene/epoxy/glass fiber composites filled with carbon black
Authors: Li Ying , Wang Shifeng , Zhang Yong , Zhang Yinxi 
Published: August 2005

AbstractThe volume resistivity and percolation thresholds of carbon black (CB) filled polypropylene (PP), PP/epoxy, and PP/epoxy/glass fiber (GF) composites were measured. The morphology of these conductive polymer composites was studied with scanning electron microscopy (SEM). The effects of the GF and epoxy contents on the volume resistivity were also investigated. The PP/epoxy/GF/CB composite exhibited a reduced percolation threshold, in comparison with that of the PP/CB and PP/epoxy/CB composites. At a given CB content, the PP/epoxy/GF/CB composite had a lower volume resistivity than the PP/CB and PP/epoxy/CB composites. SEM micrographs showed that CB aggregates formed chainlike structures and dispersed homogeneously within the PP matrix. The addition of the epoxy resin to PP resulted in the preferential location of CB in epoxy, whereas in the PP/epoxy/GF multiphase blends, because of the good affinity of CB to epoxy and of epoxy to GF, CB particles were located in the epoxy phase coated on GF. The decreased percolation threshold and volume resistivity indicated that conductive paths existed in the PP/epoxy/GF/CB composite. The conductive paths were probably formed through the interconnection of GF. Appropriate amounts of GF and epoxy should be used to decrease the volume resistivity and provide sufficient epoxy coating. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1142–1149, 2005
New polymeric materials for paper and textile conservation. I. Synthesis and characterization of acrylic copolymers
Authors: Princi Elisabetta , Vicini Silvia , Pedemonte Enrico , Arrighi Valeria , McEwen Iain 
Published: August 2005

AbstractIn the preservation of cultural heritage items, the use of polymeric materials for the consolidation and protection of artifacts with historical and artistic value is widely accepted. This area is vast and includes studies of various objects made of different materials such as wood, stone, textiles, and paper. The aim of this article is to establish the most suitable copolymer for cellulose‐based‐material restoration according to its properties, as evaluated by several techniques such as 1H‐NMR spectroscopy, size exclusion chromatography, differential scanning calorimetry, and dynamic mechanical analysis. In addition to the mechanical property evaluation, an investigation of fungal deterioration has been carried out. Because, in the literature, no complete study concerning the characterization of ethyl acrylate/methyl methacrylate and butyl acrylate/methyl methacrylate copolymers is available, a detailed and full investigation of these polymers is required before the best copolymer is selected for grafting polymerization onto cellulose. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1157–1164, 2005
Synthesis and characterization of polyacrylamide grafted copolymers of Kundoor mucilage
Authors: Mishra Anuradha , Bajpai Malvika 
Published: August 2005

AbstractIn the present research, grafting of acrylamide monomer onto a water‐soluble food grade polysaccharide, Kundoor mucilage, initiated by ceric ion in aqueous medium has been studied under N2 atmosphere. Ceric ion initiated solution polymerization was found to be satisfactory for the formation of copolymer. The effect of monomer concentration, initiator concentration, reaction time, and temperature, in terms of grafting efficiency (%GE) and percent of grafting (%PG), have been investigated. The graft copolymers were characterized by FTIR, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and X‐ray diffraction (XRD). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1186–1191, 2005
Synthesis of C60‐bonded polystyrene initiated with C60Cln/Ni(naph)2/P(Ph)3
Authors: Hua Jing , Yang Haiqiang , Guo Zhixin , Xu Ling , Chen Dianbao 
Published: August 2005

AbstractA linear‐shaped polystyrene with C60 core was prepared with a novel initiator system, C60Cln (n average value is 20)/Ni(naph)2/P(Ph)3, and Tp was 130 °C. The results of gel‐permeation chromatography detected by UV detector and fluorescence spectrum of C60‐PSt demonstrated that C60 was chemically bonded to polystyrene. The linear increasing of molecular weights (Mn,GPC) with conversion indicated that this novel initiator system had some characters of living polymerization. A bathochromic shift was found in the UV–vis spectra curves with increasing concentration of C60‐PSt in THF solution. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1215–1218, 2005
Tunable near‐infrared optical properties based on poly(methyl methacrylate)–oxide waveguide materials
Authors: Wei Ming‐Hsin , Lee Chia‐Hua , Chang Chao‐Ching , Chen Wen‐Chang 
Published: August 2005

AbstractIn this study, two classes of low‐loss optical planar waveguides were prepared from trialkoxysilane‐capped poly(methyl methacrylate) (PMMA)–silica and PMMA–titania hybrid materials, respectively. The prepared hybrid films had very uniform structure and surface planarity. The incorporation of the silica or titania segments into the acrylic polymer matrix reduced the intermolecular interaction and thus induced an increase in anharmonicity of the C‐H bond in the acrylic segment. Therefore, the third harmonic stretching vibration absorption of the C‐H bond was red‐shifted and resulted in a tuning of near‐infrared (NIR) optical absorption. The optical loss of the studied waveguides was reduced from 0.65 dB/cm of the PMMA waveguide to 0.26 and 0.28 dB/cm with increasing the silica and titania content in the hybrid materials, respectively. The reduction of the C‐H number density and shifting of the NIR absorption spectra accounted for the relationship between the optical loss and the inorganic oxide content. The increased anharmonicity through the incorporation of the inorganic moiety in the hybrid materials provides another approach for tuning the NIR optical properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1224–1228, 2005
Preparation and characterization of polypropylene/clay nanocomposites with polypropylene‐graft‐maleic anhydride
Authors: Jang Lee Wook , Kim Eung Soo , Kim Hun Sik , Yoon Jin‐San 
Published: August 2005

AbstractPolypropylene (PP)/montmorillonite (MMT) nanocomposites were prepared by the esterification of propylene‐g‐maleic anhydride (MAPP) with MMT modified with α,ω‐hydroxyamines. The structural characterization confirmed the formation of ester linkages and the interaction between the silicate layers. In particular, X‐ray diffraction patterns of the modified clays and MAPP/MMT composites showed 001 basal spacing enlargement as great as 0.14–0.62 nm according to the type of α,ω‐hydroxyamine. Thermal characterization by thermogravimetric analysis for the composites revealed increased onset temperatures of thermal decomposition. The melting peak temperature decreased, and the crystallization peak temperature increased; this indicated that MMT retarded the crystallization of MAPP. Compounding PP with MAPP/MMT composites enhanced the tensile modulus and tensile strength of PP. However, the elongation at break decreased drastically even when the MMT content was as low as 0.4–2.0 wt %. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1229–1234, 2005
Development and characterization of homogeneous membranes prepared from sulfonated poly(phenylene oxide)
Authors: Guan Rong , Gong Chunli , Lu Deping , Zou Hua , Lu Wei 
Published: August 2005

AbstractThis article investigates the comprehensive properties of sulfonated poly(phenylene oxide) (SPPO) membranes with different sulfonation degrees and presents the completion of previous work necessary for the application of SPPO membranes to proton‐exchange membrane fuel cells. The sulfonation level has been accurately determined by conductometric titration and 1H‐NMR, and the glass‐transition temperature has been obtained with both differential scanning calorimetry and dynamic mechanical thermal analysis. Sulfonic groups attached to the aromatic ring in the poly(phenylene oxide) backbone split at 220–340°C, but the main‐chain splitting temperature of SPPO is similar to that of the pure polymer. In addition, the effects of sulfonic groups and water on the tensile strength of these membranes have been studied. An increase in the sulfonate groups in the polymer results in an increase in the water uptake. Atomic force microscopy phase images of the acid‐form membranes clearly show the hydrophilic domains, and the ionic regions of the membranes with a low sulfonation degree are isolated and become connected to produce a cocontinuous morphology as the degree of sulfonation increases. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1244–1250, 2005
Liability of professional and volunteer mental health practitioners in the wake of disasters: a framework for further considerations
Authors: Abdel‐Monem Tarik , Bulling Denise 
Published: August 2005

AbstractQualified immunity from civil liability exists for acts of disaster mental health (DMH) practitioners responding to disasters or acts of terrorism. This article reviews current legal regimens dictating civil liability for potentially wrongful acts of DMH professionals and volunteers responding to disasters. Criteria are proposed to inform determinations of civil liability for DMH workers in disaster response, given current legal parameters and established tort law in relevant areas. Specific considerations are examined that potentially implicate direct liability of DMH professionals and volunteers, and vicarious liability of DMH supervisors for actions of volunteer subordinates. The relevance of pre‐event DMH planning and operationalization of the plan post‐event is linked to considerations of liability. This article concludes with recommendations to minimize liability exposure for DMH workers in response efforts. Copyright © 2005 John Wiley & Sons, Ltd.
What is terrorism and can psychology do anything to prevent it?
Authors: Stevens Michael J. 
Published: August 2005

AbstractTerrorism has a long history, which continues to unfold, and takes many forms. Notwithstanding these facts, there is no generally accepted definition of terrorism. I set forth the definitional issues that underlie the current debate about terrorism. By comparing terrorism with various forms of violence, I argue that it is plausible to construe terrorism as crime and, in support of this, I demonstrate why terrorism cannot be morally justified. Next, I cluster various immediate and long‐term approaches intended to prevent terrorism, highlighting psychologically based strategies, such as behavioral profiling, teaching tolerance and citizenship, modifying media images of terrorism, and building peace. In order to understand and respond more effectively to 21st‐century terrorism, I advocate adoption of a multidisciplinary, contextually sensitive approach. Copyright © 2005 John Wiley & Sons, Ltd.
A reassessment of state‐level covariates of militia groups
Authors: Freilich Joshua D. , Pridemore William Alex 
Published: August 2005

AbstractThis study investigated state‐level variation in the number of right‐wing militia groups. We built on prior quantitative examinations by more carefully operationalizing theoretical concepts and testing alternative hypotheses offered to account for the etiology of social movements generally and of militias specifically. Using negative binomial regression, we found that, consistent with previous research, states with higher levels of farm job loss had more militia groups. However, in contrast to prior studies, we did not find gun culture, hospitable political climate, female empowerment, or general economic deprivation to be associated with the number of militia groups. We also found no relationship between the number of militia groups and levels of fundamentalist religious culture and minority empowerment. Our study was the first to test the effects of social disorganization on the number of militias in a state, and we found the two to be positively and significantly associated. We situate our results in the theoretical and empirical literature and outline two challenges for future research. First, scholars must operationalize variables carefully since different measures of the same theoretical concept may result in diverging conclusions. Second, since one major factor (i.e., social disorganization) found in this study to be associated with the number of militia groups in a state was examined here for the first time, it is important for researchers to continue to investigate new hypotheses. Copyright © 2005 John Wiley & Sons, Ltd.
Structure and IR Spectrum of Phenylalanyl–Glycyl–Glycine Tripetide in the Gas‐Phase: IR/UV Experiments, Ab Initio Quantum Chemical Calculations, and Molecular Dynamic Simulations
Authors: Řeha D. , Valdés H. , Vondrášek J. , Hobza P. , Abu‐Riziq Ali , Crews Bridgit , de Vries Mattanjah S. 
Published: August 2005

AbstractWe investigated the potential‐energy surface (PES) of the phenylalanyl–glycyl–glycine tripeptide in the gas phase by means of IR/UV double‐resonance spectroscopy, and quantum chemical and statistical thermodynamic calculations. Experimentally, we observed four conformational structures and we recorded their IR spectra in the spectral region of 3000–4000 cm−1. Computationally, we investigated the PES by a combination of molecular dynamics/quenching procedures with high‐level correlated ab initio calculations. We found that neither empirical potentials nor various DFT functionals provide satisfactory results. On the other hand, the approximative DFT method covering the dispersion energy yields a reliable set of the most stable structures, which we subsequently investigated with an accurate, correlated ab initio treatment. The global minimum contains three moderately strong intramolecular hydrogen bonds and is mainly stabilized by London dispersion forces between the phenyl ring, the carboxylic acid group, and various peptide bonds. A proper description of the last type of interaction requires accurate correlated ab initio calculations, including the complete basis set limit of the MP2 method and CCSD(T) correction terms. Since in our beam experiments the conformations are frozen by cooling from a higher temperature, it is necessary to localize the most stable structures on the free‐energy surface rather than on the PES. We used two different procedures (rigid rotor/harmonic oscillator/ideal gas approximation based on ab initio characteristics and evaluation of relative populations from the molecular dynamic simulations using the AMBER potential) and both yield four structures, the global minimum and three local minima. These four structures were among the 15 most energetically stable structures obtained from accurate ab initio optimization. The calculated IR spectra for these four structures agree well with the experimental frequencies, which validates the localization procedure.
Synthetic Scope and Mechanistic Studies of Ru(OH)x/Al2O3‐Catalyzed Heterogeneous Hydrogen‐Transfer Reactions
Authors: Yamaguchi Kazuya , Koike Takeshi , Kotani Miyuki , Matsushita Mitsunori , Shinachi Satoshi , Mizuno Noritaka 
Published: August 2005

AbstractThree kinds of hydrogen‐transfer reactions, namely racemization of chiral secondary alcohols, reduction of carbonyl compounds to alcohols using 2‐propanol as a hydrogen donor, and isomerization of allylic alcohols to saturated ketones, are efficiently promoted by the easily prepared and inexpensive supported ruthenium catalyst Ru(OH)x/Al2O3. A wide variety of substrates, such as aromatic, aliphatic, and heterocyclic alcohols or carbonyl compounds, can be converted into the desired products, under anaerobic conditions, in moderate to excellent yields and without the need for additives such as bases. A larger scale, solvent‐free reaction is also demonstrated: the isomerization of 1‐octen‐3‐ol with a substrate/catalyst ratio of 20 000/1 shows a very high turnover frequency (TOF) of 18 400 h−1, with a turnover number (TON) that reaches 17 200. The catalysis for these reactions is intrinsically heterogeneous in nature, and the Ru(OH)x/Al2O3 recovered after the reactions can be reused without appreciable loss of catalytic performance. The reaction mechanism of the present Ru(OH)x/Al2O3‐catalyzed hydrogen‐transfer reactions were examined with monodeuterated substrates. After the racemization of (S)‐1‐deuterio‐1‐phenylethanol in the presence of acetophenone was complete, the deuterium content at the α‐position of the corresponding racemic alcohol was 91 %, whereas no deuterium was incorporated into the α‐position during the racemization of (S)‐1‐phenylethanol‐OD. These results show that direct carbon‐to‐carbon hydrogen transfer occurs via a metal monohydride for the racemization of chiral secondary alcohols and reduction of carbonyl compounds to alcohols. For the isomerization, the α‐deuterium of 3‐deuterio‐1‐octen‐3‐ol was selectively relocated at the β‐position of the corresponding ketones (99 % D at the β‐position), suggesting the involvement of a 1,4‐addition of ruthenium monohydride species to the α,β‐unsaturated ketone intermediate. The ruthenium monohydride species and the α,β‐unsaturated ketone would be formed through alcoholate formation/β‐elimination. Kinetic studies and kinetic isotope effects show that the RuH bond cleavage (hydride transfer) is included in the rate‐determining step.
A Platinium(II)‐Based Molecular Light Switch for Proteins
Authors: Vaidyanathan Vaidyanathan G. , Nair Balachandran U. 
Published: August 2005

AbstractThe platinum(II) complex [Pt(bzimpy)Cl]+ (1) [bzimpy = 2,6‐bis(benzimidazo‐2‐yl)pyridine] has been synthesized and characterized by FAB mass spectrometry and UV/Vis, NMR, and emission spectroscopy. Complex 1 emits weakly from its 3MLCT state in aqueous solution but strongly in nonaqueous media. Complex 1 exhibits a molecular light switch effect with a drastic enhancement in its emission intensity and a 72‐nm blue shift in the emission maxima in the presence of bovine serum albumin (BSA). Denaturation of BSA in the presence of 6 M urea leads to a decrease in the emission intensity of the complex, which suggests its binding to the hydrophobic pockets of the protein. In the presence of hemoglobin, however, quenching of the emission of the complex is observed due to its binding to Cys104 in subunit C and the resultant fluorescence resonance energy transfer from the platinum(II) complex to the heme. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Protein expression profiling identifies maspin and stathmin as potential biomarkers of adenoid cystic carcinoma of the salivary glands
Authors: Nakashima Dai , Uzawa Katsuhiro , Kasamatsu Atsushi , Koike Hirofumi , Endo Yosuke , Saito Kengo , Hashitani Susumu , Numata Tsutomu , Urade Masahiro , Tanzawa Hideki 
Published: August 2005

AbstractAdenoid cystic carcinoma (ACC) is one of the most common malignant tumors of the salivary glands. It tends to grow slowly but is associated with a poor prognosis compared to other malignant salivary gland tumors. To identify specific markers of ACC, we examined protein expression profiling in ACC xenograft and normal salivary glands (NSG) using fluorescent 2‐dimensional differential in‐gel electrophoresis (2‐D‐DIGE), an emerging technique for comparative proteomics, that improves the reproducibility and reliability of differential protein expression analysis between the samples. To identify the proteins, matrix‐assisted laser desorption/ionization time‐of‐flight peptide mass fingerprinting was carried out. Using these strategies, we detected 4 upregulated proteins and 5 downregulated proteins in ACC xenograft. Maspin and stathmin were selected for further analyses. Western blotting and immunohistochemical staining showed a higher expression of these proteins in ACC xenograft and clinical ACC tissue compared to NSG. Furthermore, Expression of these proteins was correlated with the histologic grading of ACC (n = 10). Therefore, our data indicate that maspin and stathmin may be not only useful biomarkers of ACC but also markers of biologic behavior in this tumor. © 2005 Wiley‐Liss, Inc.
Preschool diet and adult risk of breast cancer
Authors: Michels Karin B. , Rosner Bernard A. , Chumlea Wm. Cameron , Colditz Graham A. , Willett Walter C. 
Published: August 2005

AbstractEvents before puberty may affect adult risk of breast cancer. We examined whether diet during preschool age may affect a woman's risk of breast cancer later in life. We conducted a case‐control study including 582 women with breast cancer and 1,569 controls free of breast cancer selected from participants in the Nurses' Health Study and the Nurses' Health Study II. Information concerning childhood diet of the nurses at ages 3–5 years was obtained from the mothers of the participants with a 30‐item food‐frequency questionnaire. An increased risk of breast cancer was observed among woman who had frequently consumed French fries at preschool age. For one additional serving of French fries per week, the odds ratio (OR) for breast cancer adjusted for adult life breast cancer risk factors was 1.27 (95% confidence interval [CI] = 1.12–1.44). Consumption of whole milk was associated with a slightly decreased risk of breast cancer (covariate‐adjusted OR for every additional glass of milk per day = 0.90; 95% CI = 0.82–0.99). Intake of none of the nutrients calculated was related to the risk of breast cancer risk in this study. These data suggest a possible association between diet before puberty and the subsequent risk of breast cancer. Differential recall of preschool diet by the mothers of cases and controls has to be considered as a possible explanation for the observed associations. Further studies are needed to evaluate whether the association between preschool diet and breast cancer is reproducible in prospective data not subject to recall bias. © 2005 Wiley‐Liss, Inc.