bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on synthesis and conductivity of ferrocenyl Schiff base and its salt
Authors: Liu Wei‐Jun , Xiong Guo‐Xuan , Wang Wei‐Ping 
Published: December 2006

AbstractFerrocenyl Schiff base was synthesized through the condensation of ferrocenecarboxaldehyde and p‐phenylenediamine under neutral conditions, and then a new interesting category of organometallic charge transfer complex was obtained by the doping of ferrocenyl Schiff base with Fe3+, Al3+ and Ti3+ salts. The effects of the dosage of doping agent and doping temperature on the room‐temperature electric conductivity of samples were discussed; in addition, the temperature dependence of the electric conductivity of samples was studied, their structures and compositions were characterized by 1H‐NMR spectra, infrared spectra, ultraviolet spectra and an electron probe X‐ray microanalyser. The results showed that the electric conductivity of sample can increase 4–5 orders of magnitude after doping with a metallic salt, and the electric conductivity has a positive temperature coefficient effect. The electrical activation energies of the complexes in the range 0.09–1.54 eV were calculated from Arrhenius plots, indicating their favourable semiconducting behaviour. Copyright © 2006 John Wiley & Sons, Ltd.
Bioaccumulation of metals and induction of metallo‐ thioneins in selected tissues of common carp (Cyprinus carpio L.) co‐exposed to cadmium, mercury and lead
Authors: Huang Zhi‐Yong , Zhang Qiang , Chen Jing , Zhuang Zhi‐Xia , Wang Xiao‐Ru 
Published: December 2006

AbstractThe concentrations of mercury (Hg), cadmium (Cd) and lead (Pb) at various exposure periods were determined in the gill, kidney, liver and muscle of common carp (Cyprinus carpio L.) co‐exposed to 1.0 µg ml−1 each of Cd2+, Hg2+ and Pb2+ for up to 10 days. Metallothionein fractions (MTs) in these organs were characterized using the hyphenated technique of size‐exclusion chromatography (SEC) and inductively coupled plasma mass spectrometry (ICP‐MS). After 10 days of exposure, maximum toxic metal concentrations of Hg, Cd and Pb were 10.7 (gill), 0.145 (kidney) and 0.112 µg g−1dryweight (gill), respectively. The pattern of accumulation of Hg and Pb was in the order gill > kidney > liver > muscle. In the case of Cd, accumulation was in the order kidney > gill > liver > muscle. Cd and Hg binding MTs were significantly induced in the gill, kidney and liver of all the exposure groups in comparison with the control group (p < 0.05), and the amounts of them increased with the longer exposure time. Despite the higher intracellular Hg concentration and the stronger HgSH binding affinity, the amount of Cd‐binding MTs was much higher than that of Hg‐binding MTs. The results indicate that MT synthesis in these organs was clearly metal‐specific. MTs in gill may be used as a bio‐marker to detect the metal pollution caused by Hg and Cd. Zinc and copper binding MTs in the organs of the exposed fish were also increased. This may be due to the MTs' important role in the homeostatic regulation of essential metals and their protective role against the acute toxicity of non‐essential metals. Even though there was considerable accumulation of lead in the organs of the exposed fish, Pb‐binding MT synthesis was non‐significant. Copyright © 2006 John Wiley & Sons, Ltd.
The determination of methylmercury in biological samples by HPLC coupled to ICP‐MS detection
Authors: Vidler Daniel S. , Jenkins Richard O. , Hall John F. , Harrington Chris F. 
Published: December 2006

AbstractThe use of high‐performance liquid chromatography (HPLC) coupled to inductively coupled plasma mass spectrometry (ICP‐MS) for the determination of methylmercury (MeHg+) in fish tissue and hair samples is described. Analysis of these sample types is required when carrying out biomonitoring studies to determine human dietary exposure to this toxic mercurial compound. The developed method used a mobile phase containing an organic modifier and a sulfydryl compound (1:1 v/v methanol:water containing 0.01% v/v 2‐mercaptoethanol) to limit peak tailing and aid separation. The chromatographic separation was coupled to the ICP‐MS detector via a short piece of PEEK tubing, attached to the nebulizer. A cooled spraychamber and oxygen addition post‐nebulization were required to limit the solvent loading on the plasma and reduce carbon build‐up on the cones, respectively. The sample preparation procedure employed a drying step followed by digestion of the sample using tetramethylammonium hydroxide (TMAH) and heating in an open vessel microwave system. Two fish tissue certified reference materials (CRM), tuna fish CRM 463 and 464 (BCR, Brussels), a tuna fish proficiency test sample, IMEP‐20 (IRMM, Geel, Belgium) and a hair CRM NIES no. 13 (National Institute of Environmental Science, Japan), were used to evaluate the method. The recovery of MeHg+ for these four materials was between 83 and 100%, with precisions better than 6% for three separate extractions of the different materials. The limit of quantitation for MeHg+ using the developed protocol was 0.5 µg Hg g−1. The stability of MeHg+ in the fish sample extracts was also assessed and losses of 14–16% were observed after storage of the extracts in a refrigerator at 5 °C, in high‐density polypropylene tubes, for 6 months. The developed protocol has been used previously with atmospheric pressure ionization mass spectrometry (API‐MS) to provide structural characterization and also with calibration via isotope dilution (IDMS) to provide high accuracy quantitation. Copyright © 2006 John Wiley & Sons, Ltd.
Chemical synthesis, characterization, and direct‐current conductivity studies of polypyrrole/γ‐Fe2O3 composites
Authors: Murugendrappa M. V. , Prasad M. V. N. Ambika 
Published: December 2006

AbstractThe in situ polymerization of pyrrole was carried out in the presence of γ‐Fe2O3 to synthesize polypyrrole/γ‐Fe2O3 composites by a chemical oxidation method. The polypyrrole/γ‐Fe2O3 composites were synthesized with various compositions, including 10, 20, 30, 40, and 50 wt % γ‐Fe2O3 in pyrrole. The polypyrrole/γ‐Fe2O3 composites were characterized with X‐ray diffractometry and infrared spectroscopy. The surface morphology of these composites was studied with scanning electron microscopy. The direct‐current conductivity was studied from 40 to 200°C. The dimensions of the γ‐Fe2O3 particles in the matrix had a greater influence on the conductivity values. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2797–2801, 2007
Synthesis of cationic flocculants by the inverse microemulsion copolymerization of acrylamide with 60% 2‐acryloxyethyltrimethyl ammonium chloride in the monomer feed. I. Initiation by ammonium persulfate/sodium disulfite redox system
Authors: Escudero Sanz F. J. , Ochoa Gómez J. R. , Sasia P. M. , de Apodaca E. Díaz , Río P. 
Published: December 2006

AbstractAcrylamide/2‐acryloxyethyltrimethyl ammon‐ium chloride copolymers in inverse microemulsion, with a cationic charge density of 60% and a concentration of active matter of 30 wt %, of interest as flocculants have been obtained by inverse microemulsion copolymerization. Interesting inverse microemulsion formulations from both industrial and economical standpoints were selected from pseudoternary phase diagrams. These formulations were polymerized by semicontinuous free radical copolymerization in inverse microemulsion using sodium disulfite and ammonium persulfate as initiators. Influence of initiators and initiator addition conditions (specific flow rate and concentration) on semicontinuous polymerization and final product properties as flocculants have been studied. A strong difference in copolymer solution viscosity has been found when an aqueous solution of sodium disulfite is used as initiator instead of sodium disulfite/ammonium persulfate couple redox, specially for low sodium disulfite solution feeding flow. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2826–2836, 2007
Condensation reactions of phenolic resins. VI. Dependence of the molecular association of 2,4,6‐trihydroxymethylphenol on the concentration in an aqueous alkaline medium
Authors: Kamo Naruyuki , Kondo Tetsuo , Morita Mitsuhiro 
Published: December 2006

AbstractThe concentration dependence of the molecular association of 2,4,6‐trihydroxymethylphenol (THMP) as a model compound for phenol–formaldehyde resin was studied. 13C‐NMR spin–lattice relaxation time (T1) measurements indicated that the molecular interactions were influenced by the concentration of THMP. Plots of T1 versus the concentration revealed an inflection point around 1.2 mol/L. Molecular orbital calculations of the THMP molecules implied the following features of the molecular interactions: in the concentration range below 1.0 mol/L, THMP existed as a single molecule, and then at a higher concentration, self‐association started. At concentrations higher than 1.5mol/L, almost all the THMP molecules were bimolecularly associated, and the formation of larger clusters was initiated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2849–2854, 2007
New method for evaluating adhesive property of fabrics and TPU: The rigid‐body pendulum rheometer approach
Authors: Chiu H. T. , Lee Patricia T. C. 
Published: December 2006

AbstractCoating and laminating processes play an important role in textile industry. They are frequently used to produce fabric laminates during which the physical properties and appearance of textile fabrics are modified and enhanced. Currently, the adhesive property testing of a fabric laminate is done so by the use of pulling test machines such as Universal Tensile Tester, which measures the strength required to peel the tested materials apart. The adhesive test to date has not yet been performed using a newly developed machine, Rigid‐Body Pendulum Rheometer (RPR). This study was to establish a more effective method for fast‐evaluating adhesive properties of fabric laminates by assessing the performance of RPR. Specifically, RPR and Universal Tensile Tester were used to measure, respectively, the viscosity and peeling strength of PET/TPU (thermoplastic polyurethane) and nylon/TPU in response to UV exposure and water immersion. RPR can continuously observe and record viscosity behavior of tested samples in various temperature condition including from low temperature to high temperature, it not only measures viscosity speed, it also detects the differences in crosslinking and measures data generated during the softening process when the balanced time was achieved during the oscillations procedure. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2855–2863, 2007
Fundamental characterization of SBS‐modified asphalt mixed with sulfur
Authors: Chen J. S. , Huang C. C. 
Published: December 2006

AbstractThe purpose of this study was to characterize the mechanical behavior of asphalt modified by styrene–butadiene–styrene (SBS) and sulfur. Viscosity, microscopy, and rheological tests were conducted to understand the engineering properties of the polymer‐modified asphalt (PMA). Without the addition of sulfur, the polymer‐modified asphalt was microheterogeneous and was made up of two distinct finely interlocked phases, especially at high SBS concentrations. After the addition of sulfur, the PMA was observed to have smaller asphalt domains and a fairly homogeneous dispersion of the asphalt in the SBS matrix. The compatibility between polymer and asphalt produced an elastic network into the asphalt. The addition of sulfur resulted in an excellent elastic system and substantially increased the rheological properties of the PMA. Because of the colloidal nature of asphalt cements, their engineering properties were greatly improved because of the reinforcement of the SBS polymer and the physical‐chemical interaction between SBS and asphalt. The difference in the softening point between the top and bottom layers decreased significantly, and elastic recovery increased when was sulfur was present. A viscoelastic model was examined and shown to be appropriate for predicting the rheological properties ofthe asphalt–SBS blend mixed with sulfur. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2817–2825, 2007
Emulsifier‐free emulsion polymerization of styrene with 4‐vinylbenzoic acid: Kinetics and distribution of the carboxyl groups
Authors: Prasath R. Arun , Margarit‐Puri K. , Klapper M. 
Published: December 2006

AbstractCarboxylated polystyrene particles were prepared by the batch emulsion polymerization of styrene (Sty) with 4‐vinylbenzoic acid (VBA) in the absence of an emulsifier with K2S2O8 as a free‐radical initiator. The effect changes in the ratio of potassium hydroxide to VBA and the concentration of VBA to Sty on the kinetics, monomer conversion, distribution of carboxyl groups, and particle size distribution were analyzed. The stability of the latices was evaluated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2910–2919, 2007
On the overdrawing of melt‐spun isotactic polypropylene tapes
Authors: Schimanski Tilo , Loos Joachim , Peijs Ton , Alcock Ben , Lemstra Piet J. 
Published: December 2006

AbstractThe morphology and mechanical properties of melt‐spun and post‐drawn isotactic polypropylene (iPP) tapes have been studied in order to examine their dependence on the post‐draw ratio applied. Special attention is focused on the characterization of the so‐called overdrawing behavior of the tapes; at a certain draw ratio, a change of the optical appearance of the tape from transparent to opaque is observed. Overdrawing is accompanied with changes in the mechanical properties, surface, and morphology of the tapes. For post‐draw ratios without overdrawing, and for highly overdrawn tapes, the variation in the mechanical properties measured is very small, but for slightly overdrawn tapes, a large scattering of mechanical properties has been measured. In the latter case, this behavior is related to the start of internal delamination of the tapes during post drawing. It is shown that strongly overdrawn tapes have excellent mechanical properties, in particular, high specific stiffness and strength. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2920–2931, 2007
Solubility measurements of N2 and CO2 in polypropylene and ethene/octene copolymer
Authors: Li G. , Gunkel F. , Wang J. , Park C. B. , Altstädt V. 
Published: December 2006

AbstractIn this set of experiments a magnetic suspension balance (MSB) was employed to measure the apparent solubilities of N2 and CO2 in polypropylene (PP) and ethene/octene copolymer melts, while the swollen volume predicted by the Sanchez–Lacombe (SL) equation of state (EOS) was used to account for the buoyancy effect. The swollen volume of the polymer/gas mixture, as well as the gas solubilities for both PP and the ethene/octene copolymer, are discussed. It was observed that the branched molecular structure limited the molecular movement, and therefore the volume swelling of the polymer/gas mixture. In a similar context, the solubility of both N2 and CO2 were less in the branched polymer (ethene/octene copolymer) than in the linear PP. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2945–2953, 2007
Synthesis and characterization of carboxymethylated red angico (Anadenanthera macrocarpa) exudate polysaccharide
Authors: Oliveira Marilia A. , Silva Durcilene A. , Uchoa Daniel E. A. , Maciel Jeanny S. , Feitosa Judith P. A. , Paula Haroldo C. B. , de Paula Regina C. M. 
Published: December 2006

AbstractRed angico is a heteropolysaccharide (arabinogalactan) obtained from Anadenanthera macrocarpa trees. Carboxymethylation of angico gum (AG) with monochloroacetic acid (MCA) in alkaline aqueous medium resulted in samples which were characterized by 13C nuclear magnetic resonance spectroscopy and gel permeation chromatography. The effects of reaction parameters, such as alkali concentration, MCA/AG ratio and temperature on the reaction yield and degree of substitution (DS) were investigated. The DS and MCA total efficiency values increase up to 2 h reaction time and then decrease. The DS varied from 0.11 to 1.10 depending on NaOH/MCA/AG ratio and temperature. The highest MCA total efficiency (0.57) was obtained for NaOH/MCA/AG molar ratio equal to 3:1:1, at 70°C. (DS = 0.63, yield = 91.0%). Nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) analysis shows that polymer degradation was observed in all samples. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2985–2991, 2007
Effects of spinning speed and heat treatment on the mechanical properties and biodegradability of poly(lactic acid) fibers
Authors: Park Chung Hee , Hong Eun Young , Kang Yun Kyung 
Published: December 2006

AbstractWe undertook this study to suggest the optimal spinning process conditions that provide a proper range of tenacity and biodegradability in textile fibers. The effect of melt‐spinning speed and heat treatment on the mechanical properties and biodegradability of poly(lactic acid) (PLA) fibers were investigated. PLA was spun at a high spinning speed of 2000–4000 m/min, and each specimen was heat‐treated. Mechanical properties were estimated by measurement of the breaking stress, and the degree of crystallinity was evaluated with wide‐angle X‐ray scattering. Biodegradability was estimated from the decreases in breaking stress, weight loss, and degree of crystallinity after soil burial. The results of the experiment reveal that heat treatment of the PLA fibers increased the breaking stress and crystallinity. With increasing spinning speed, breaking stress and crystallinity also increased. An increase in spinning speed was more effective than an increase in heat treatment for enhancing the breaking stress within the range of this study. From the soil burial test, it was revealed that an increase in spinning speed and heat treatment decreased the biodegradability of the fibers. X‐ray analysis of the soil‐buried fibers showed that fibers with higher crystallinities began to degrade more slowly. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3099–3104, 2007
Preparation and properties of recycled HDPE/clay hybrids
Authors: Lei Yong , Wu Qinglin , Clemons Craig M. 
Published: December 2006

AbstractHybrids based on recycled high density polyethylene (RHDPE) and organic clay were made by melt compounding. The influence of blending method, compatibilizers, and clay content on clay intercalation and exfoliation, RHDPE crystallization behavior, and the mechanical properties of RHDPE/clay hybrids were investigated. Both maleated polyethylene (MAPE) and titanate could improve the compatibilization of RHDPE and clay. RHDPE/clay hybrids containing completely exfoliated clay were obtained using a two‐step blending method. Without compatibilizers, the clay could not be exfoliated, and it lowered the crystallization peak temperature, crystallinity level, and the long period of RHDPE. MAPE and clay layers could act as heterogeneous nucleating agents for RHDPE. The titanate had a little influence on crystallization behavior of RHDPE. Adding clay to RHDPE reduced the impact strength but had little influence on the tensile strength. Both the storage and loss moduli increased with up to 5% of clay in hybrids containing CAPS, and there was an about 44% increase in impact strength of RHDPE/clay hybrid containing 5% MAPE compared with that of the hybrid containing no MAPE. The clay presence lowered the thermal stability of RHDPE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3056–3063, 2007
Synthesis and characterization of composite magnetic microspheres of artemisia seed gum and chitosan
Authors: Zhang Ji , Zhang Shengtang , Wang Yunpu , Gao Sufang 
Published: December 2006

AbstractIn this study, composite magnetic microspheres of artemisia seed gum and chitosan were prepared in a well‐shaped spherical form with a size range of 230–460 μm by the suspension crosslinking technique for use in the application of magnetic carrier technology. The magnetic material used in the preparation of the composite microspheres was prepared by precipitation from FeCl3 and FeSO4 solution in basic medium. The morphological, magnetic properties, and the functional groups of the microspheres were characterized by different techniques (i.e., SEM, magnetometry, and FTIR). The results demonstrated that the stirring rate of the suspension and the Fe3O4/chitosan ratio are the most effective parameters for the average of the size distributions and the magnetic quality of the microspheres, while the amount of artemisia seed gum and Tween‐80 have no significant effect on these properties. The best magnetic quality of the composite magnetic microspheres is around 4.08 emu/g microspheres at 10 KG magnetic field intensity. The thermal stability of the composite magnetic microspheres was measured by using DSC methods. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3045–3049, 2007
Preparation and characterization of carboxymethyl konjac glucomannan/sodium montmorillonite hybrid films
Authors: Lu Jun , Xiao Chaobo 
Published: December 2006

AbstractCarboxymethyl konjac glucomannan (CKGM)/ sodium montmorillonite (MMT) hybrid films of various compositions were prepared by casting from a polymer/silicate water suspension. The structure and properties of the hybrid films were investigated by wide angle X‐ray diffraction (WAXD), transmission electron microscopy (TEM), attenuated total reflection infrared spectroscopy (ATR‐IR), differential scanning calorimetry (DSC), and tensile tests. The results from WXRD and TEM indicated that an intercalated CKGM/MMT nanocomposite film was obtained by polymer solution intercalation. WXRD and DSC showed that the high‐Tm crystal phase was induced by the presence of lower MMT loading, but the Tm of the hybrid films became weak with the increase of MMT content due to the polymer confinement. The hybrid films showed higher thermal stability and mechanical properties than that of the neat polysaccharide due to the strong interaction between hydroxyl and carbonyl group of CKGM and the silicate layer of MMT. Furthermore, the degree of swelling of the hybrid films was investigated in acidic buffer solutions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2954–2961, 2007
Effect of halide ions on the corrosion inhibition of aluminium in alkaline medium using polyvinyl alcohol
Authors: Umoren S. A. , Ebenso E. E. , Okafor P. C , Ekpe U. J. , Ogbobe O. 
Published: December 2006

AbstractThe corrosion inhibition of aluminum in NaOH in the presence of polyvinyl alcohol (PVA) at 30 and 40°C and the effect of addition of halides (KCl, KBr, KI) were studied using weight loss and hydrogen evolution methods. Results obtained showed that PVA acts as a corrosion inhibitor in the alkaline environment. The inhibition efficiency increased with increase in concentration of PVA and synergistically increased on the addition of the halides but however decreased with rise in temperature. The phenomenon of physical adsorption is proposed from the obtained Ea and Qads values. PVA was found to obey Freundlich and Frumkin adsorption isotherms. The increase in inhibition efficiency I (%), surface coverage θ values as well as synergistic parameter, SI were found to be in the order I− > Br− > Cl−, which clearly indicates that the radii and electronegativity of the halides play a significant role in the adsorption process. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2810–2816, 2007