bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ion-Association and Solvation of Some Copper (I), Silver (I) and Tetraalkylammonium Salts in Binary Mixtures of Acetonitrile withn-Butyronitrile and N,N-Dimethylacetamide
Authors: Gill Dip Singh , Kumari Avnesh , Gupta Rahul , Jauhar S. P. , Puri J. K. 
Published: September 2005

AbstractMolar conductances of Bu4NBPh4, Bu4NClO4, Bu4NI, Bu4NBr, Bu4NCF3COO, Pr4NBr, Et4NI, Et4NBPh4, NaClO4, NaBPh4, [Cu(CH3CN)4]ClO4and CF3COOAg have been measured in the concentration range (1–120) × 10−4mol dm−3in acetonitrile (AN) and binary mixtures of AN withn-butyronitrile (n-BTN) and DMA. The conductance data in all cases have been analyzed by the Shedlovsky method to evaluate ΛoandKAof these electrolytes. Some of these salts are associated in these solvent systems. Ion-association in case of silver (I) salts is the largest and relatively more in case of AN + DMA mixtures. Limiting ion conductances (λio) and hence actual solvated radii (ri) in all solvent systems have been evaluated using a modified form of Stoke's law. Cu+, Ag+and Na+are highly solvated, CF3COO−, ClO4−, Br−and I−are poorly/moderately solvated and tetraalkylammonium ions (R4N+) and Ph4B−are not solvated in AN +n-BTN and AN + DMA mixtures.
Solvation of the Ionic Liquid [C4mim][PF6] in Aqueous Ethanol Solutions from Molar Volume, Viscosity and Conductivity Measurements
Authors: Wang Jianji , Han Lijun , Zhao Yang , Pei Yuanchao 
Published: September 2005

Abstract
Standard partial molar volumes V
2,Φ
0, viscosity B-coefficients and molar conductivities λm for the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate [C4mim][PF6] in aqueous ethanol solutions (x
ethanol = 0.5∼0.9) have been determined from density, viscosity and conductivity measurements at 298.15 K. It is shown that values of V
2,Φ
0 decrease, while those of viscosity B-coefficients increase with increasing mole fraction of ethanol in the solvents. The molar conductivities of the ionic liquid are found to be decreased with increase of both the ionic liquid concentration and the ethanol content in the systems. Experimental results have been discussed in terms of the ionic liquid–solvent interactions and the ion associations of the ionic liquid in aqueous ethanol solutions.
Nanosized TiO2‐filled sulfonated polyethersulfone proton conducting membranes for direct methanol fuel cells
Authors: Prashantha K. , Park S. G. 
Published: September 2005

AbstractThis paper presents an evaluation of the effect of titanium dioxide nanoparticles in sulfonated polyethersulfone with sulfonation degree of 70%. A series of inorganic–organic hybrid membranes was prepared with a systematic variation of titanium dioxide nanoparticles content. Their water uptake, methanol permeability, and proton conductivity as a function of temperature were investigated. The results show that the inorganic oxide network decreases the proton conductivity and water swelling. Increase in inorganic oxide content leads to decrease of methanol permeability. In terms of morphology, membranes are homogeneous and exhibit good adhesion between inorganic domains and the polymer matrix. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1875–1878, 2005
Particle size and distribution of biodegradable poly‐D,L‐lactide‐co‐poly(ethylene glycol) block polymer nanoparticles prepared by nanoprecipitation
Authors: Ren Jie , Hong Haiyan , Song Jinxing , Ren Tianbin 
Published: September 2005

AbstractA biodegradable block copolymer, poly‐D,L‐lactide (PLA)‐co‐poly(ethylene glycol) (PEG), was prepared by the ring‐opening polymerization of lactide with stannous caprylate [Sn(Oct2)] as a catalyst; then, the PLA–PEG copolymer was made into nanoparticles by nanoprecipitation under different conditions. The average molecular weight and structure of PLA–PEG were detected by 1H‐NMR and gel permeation chromatography. The sizes and distributions of the nanoparticles were investigated with a laser particle‐size analyzer. The morphologies of the nanoparticles were examined by transmission electron microscopy. The effects of the solvent–nonsolvent system, operation conditions, and dosage of span‐80 on the sizes and distributions of the nanoparticles are discussed. The results show that acetone–water was a suitable solvent–nonsolvent system and the volume ratio of the nonsolvent phase to the solvent phase (O/W) (v/v), the concentration of PLA–PEG in the solvent phase, and the dosage of span‐80 had important effects on the particle sizes and distributions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1884–1890, 2005
Hydrophilic functional copolymers from N‐maleoyl glycine and hydroxymethylacrylamide: Synthesis, characterization, and thermal properties
Authors: del C. Pizarro Guadalupe , Jeria Manuel , Marambio Oscar G. , Huerta Margarita , Rivas Bernabé L. 
Published: September 2005

AbstractThe free‐radical copolymerization of N‐maleoylglycine with hydroxymethylacrylamide was studied, with the starting monomer compositions ranging from 25 to 75 mol %. The copolymer compositions were obtained by elemental analysis from the N/C weight percentage ratio. The monomer reactivity ratios were estimated by the classical Fineman–Ross and Kelen–Tüdös linear procedure methods. The experimental data indicated random comonomer incorporation. The thermal behavior of the copolymers was investigated with differential scanning calorimetry and thermogravimetry techniques under a nitrogen atmosphere. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1903–1908, 2005
Characterization and transport properties of a novel aliphatic polyamide with an ethyl branch
Authors: Kanekura K. , Tsujita Y. , Yoshimizu H. , Okamoto S. , Kunisada H. , Goto M. 
Published: September 2005

AbstractThe CO2 gas and water vapor transport properties of a novel aliphatic polyamide with an ethyl branch were investigated. The polymer was characterized with density measurements, differential scanning calorimetry, thermogravimetric analysis, and wide‐angle X‐ray diffraction analyses, and the amorphous and glassy nature of the polymer at the ambient temperature were confirmed. The CO2 sorption isotherm of the polymer appeared to obey the dual‐mode sorption isotherm, which was characteristic of the glassy state. The water vapor sorption below a relative humidity of 0.4 or 0.5 was explained in terms of the Brunauer–Emmett–Teller sorption mechanism, whereas that at a high relative humidity demonstrated a dissolution type of water vapor into the polyamide. The permeability coefficients of He, CO2, O2, and N2 gases through the membrane were as follows: P(He) > P(CO2) > P(O2) > P(N2). The novel polyamide membrane was more permeable to CO2, O2, and N2 gases than nylon 6 and nylon 66 membranes, containing a crystalline and hydrogen‐bonding nature. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1955–1960, 2005
Fast liquefaction of bagasse in ethylene carbonate and preparation of epoxy resin from the liquefied product
Authors: Xie Tao , Chen Fangeng 
Published: September 2005

AbstractBagasse was rapidly liquefied in ethylene carbonate catalyzed by sulfuric acid at 140–170°C. The liquefaction was finished within 18 min. The liquefaction product was a mixture of polyols and phenolic compounds. The hydroxyl number of liquefied bagasse was in the range of 200–330 mg of KOH/g. The liquefied bagasse comprised two major fractions with different molecular weights. The average molecular weight of each fraction changed little during the liquefaction procedure, but the ratio of the content of the two fractions varied with time. An epoxy resin was prepared from the liquefied bagasse and diglycidyl ether of bisphenol A. The resin was cured with triethylene tetramine at 100°C. The resin presented higher adhesive shear strength and better thermal stability than a commercial epoxy resin. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1961–1968, 2005
Rapid liquid chromatography–tandem mass spectrometry method for quantification of ziprasidone in human plasma
Authors: Al‐Dirbashi Osama Y. , Aboul‐Enein Hassan Y. , Al‐Odaib Ahmed , Jacob Minnie , Rashed Mohamed S. 
Published: September 2005

AbstractA liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method for the determination of ziprasidone (ZIP) in human plasma was developed. ZIP and N‐methyl ziprasidone as internal standard (IS) were extracted from alkalinized plasma using tert‐ butyl methyl ether. Separation was performed isocratically on a C8 column with 90% acetonitrile containing 2 mmol/L ammonium acetate as a mobile phase with a total run time of 2.5 min. MS/MS transitions of m/z 413 &rarr; 194 and m/z 427 &rarr; 177 of the analyte and internal standard were used for quantification. Confirmatory ions of m/z 413 &rarr; 177 and m/z 427 &rarr; 180 were collected as well. The calibration curve based on peak‐area ratio was linear up to at least 200 ng/mL with a detection limit of 0.1 ng/mL. The method showed satisfactory reproducibility with a coefficient of variation of less than 5%. The method was successfully applied to the analysis of ZIP in spiked human plasma. Copyright © 2005 John Wiley & Sons, Ltd.
Psychological model for animating crowded pedestrians
Authors: Sakuma Takeshi , Mukai Tomohiko , Kuriyama Shigeru 
Published: September 2005

AbstractThis paper proposes a psychological model for simulating pedestrian behaviors in a crowded space. Our decision‐making scheme controls plausible avoidance behavior depending on the positional relations among surrounding persons, on the basis of a two‐stage personal space and a virtual memory structure as proposed in social psychology. Our system determines pedestrian walking speed with the crowd density to imitate the measured data in urban engineering, and automatically generates plausible motions of the individual pedestrian by composing a locomotion graph with motion capture data. Our approach based on psychology and a variety of actual measurements can increase the accuracy of simulation at both the micro and macro levels. Copyright © 2005 John Wiley & Sons, Ltd.
Modeling and simulating the deformation of human skeletal muscle based on anatomy and physiology
Authors: Lemos Robson R. , Rokne Jon , Baranoski Gladimir V. G. , Kawakami Yasuo , Kurihara Toshiyuki 
Published: September 2005

AbstractThis paper describes the modeling and simulation of the deformation of human skeletal muscle at different structural levels based on sound scientific principles, experimental evidence, and state‐of‐art muscle anatomy and physiology. The equations of a continuum model of a muscle with realistic architecture, including internal arrangement of muscle fibers and passive structures, and deformation, including activation relations, was developed and solved with the finite element method. The continuum model is used as the basis of a strategy for controlling muscle deformation using activation relations. In order to demonstrate the functionality of the model, it was used to investigate force production and structural changes during contraction of the human tibialis anterior for maximally and submaximally activated muscle behavior. From a comparison with experimental data obtained from ultrasound imaging, we concluded that the modeling and simulation of the continuum based on physiologically meaningful parameters as described in the paper is both an excellent predictor of force production observations and of changes in internal geometry under various test conditions. It is therefore a valuable tool for controlling muscle deformation during movement. Copyright © 2005 John Wiley & Sons, Ltd.
Motion control with strokes
Authors: Oshita Masaki 
Published: September 2005

AbstractWe present a novel interface for interactive and intuitive motion control of human figures. By drawing a stroke on the screen using a pen or a mouse, a user of our system can make virtual human figures perform various types of motions. An important feature of ‘stroke’ is that it has initial and terminal points. With a single stroke, users can specify the source and target of an action at the same time. An appropriate action is determined based on single stroke and the context. For example, by drawing a stroke from the foot of a character to a ball, the character kicks the ball. By drawing a stroke from a prop to one of the character's hands, the character takes the prop with the specified hand. By drawing a stroke from a character to any point on the ground, the character walks to the specified position. First, we categorize selectable objects into some types. The motions are then described using combinations of the defined types. We also detail the implementation of our system and the methods for motion generation, and finally we discuss some issues based on experiments with the implemented system. Copyright © 2005 John Wiley & Sons, Ltd.
Covalent Incorporation of Methyl Red Dyes into Double‐Stranded DNA for Their Ordered Clustering
Authors: Kashida Hiromu , Tanaka Masayuki , Baba Seiki , Sakamoto Taiichi , Kawai Gota , Asanuma Hiroyuki , Komiyama Makoto 
Published: September 2005

AbstractAn ordered dye cluster of Methyl Reds was formed in double‐stranded DNA by hybridizing two complementary DNA–dye conjugates, each involving a Methyl Red moiety on a threoninol linker and a 1,3‐propanediol spacer arranged alternately in the middle of the DNA sequence. In the duplex, Methyl Reds from each strand were axially stacked antiparallel to each other, as determined from NMR analysis. This clustering of Methyl Reds induced distinct changes in both UV/Vis and CD spectra. Single‐stranded DNA–Methyl Red conjugates on D‐threoninol linkers and (1,3‐propanediol) spacers exhibited broad absorption spectra with λmax at around 480 nm, and almost no CD was observed at around the absorption maximum of Methyl Red. However, as Methyl Reds were clustered by hybridization, λmax shifted towards shorter wavelengths with respect to its monomeric transition. This hypsochromic shift increased as the number of Methyl Red molecules increased. Furthermore, a positive couplet was also strongly induced here. These dye clusters are H‐aggregates, in which molecular excitons are coupled. The positive couplet demonstrates that the clusters on D‐threoninol form a right‐handed helix. In contrast, the induced CD became much weaker with Methyl Red on L‐threoninol, which intrinsically prefers counterclockwise winding. Thus, mutual orientation of the stacked dye molecules was controlled by the chirality of the linker.
Grafting of [Mn(CH2tBu)2(tmeda)] on Silica and Comparison with Its Reaction with a Silsesquioxane
Authors: Riollet Virginie , Quadrelli Elsje Alessandra , Copéret Christophe , Basset Jean‐Marie , Andersen Richard A. , Köhler Klaus , Böttcher Rolf‐Michael , Herdtweck Eberhardt 
Published: September 2005

AbstractThe reaction of [Mn(CH2tBu)2(tmeda)] (1) and a silica partially dehydroxylated at 700 °C (SiO2/700) yields a single surface species [(SiO)Mn(CH2tBu)(tmeda)] (2 a; tmeda=tetramethylethylendiamine), while a mixture of 2 a and [(SiO)2Mn(tmeda)] (2 b) is obtained by using SiO2/200, SiO2/300, or SiO2/500 as evidenced by mass balance analysis, and IR and EPR spectroscopy. The reaction of 1 and (c‐C5H9)7Si7O12SiOH (3), a soluble silanol that is a molecular model for a silica support, generates the bis‐siloxy complex 4, [{(c‐C5H9)7Si7O12SiO}2Mn(tmeda)2], in a quantitative yield; compound 4 was characterized by single‐crystal X‐ray diffraction. These reactions exemplify the limitation of considering molecular silanol derivatives as straightforward and reliable homogeneous models for silica, and address the need for thorough characterization of surface species by the use of surface‐science techniques. These studies show the possibility of preparing coordinatively and geometrically unique surface species that would be difficult to prepare by solution chemistry methods; insights into the chemical and physical properties of these surface species are also gained.
Controlled Self‐Assembly of Amphiphilic Oligopeptides into Shape‐Specific Nanoarchitectures
Authors: Koga Tomoyuki , Higuchi Masahiro , Kinoshita Takatoshi , Higashi Nobuyuki 
Published: September 2005

AbstractHere, we report a novel, programmable, molecular self‐assembling system to fabricate shape‐specific, three‐dimensional nanoarchitectures. Three types of simple 16‐mer peptides consisting of hydrophobic Leu and hydrophilic Lys, LKL16, KLK16, and LK16, were prepared as building blocks for nanofabrications. A detailed analysis of the conformation and self‐assembling mechanism was performed by using circular dichroism (CD), FTIR spectroscopy, and atomic force microscopy (AFM). A wide variety of self‐assembled nanoarchitectures, such as β‐sheet‐plates, β‐sheet‐fibers, α‐helix‐particles, and α‐helix‐plates, could be fabricated by tuning the peptide sequence, reaction time, and solution pH. The ability to control the self‐assembled nanostructures should provide a simple and/or essential insight into the mechanism of peptide aggregation, including amyloid formation, and it should be useful for the design of novel bio‐related nanomaterials.
Mechanistic Insights into Iridium‐Catalyzed Asymmetric Hydrogenation of Dienes
Authors: Cui Xiuhua , Fan Yubo , Hall Michael B. , Burgess Kevin 
Published: September 2005

AbstractHydrogenation of 2,3‐diphenylbutadiene (1) with the chiral carbene–oxazoline–iridium complex C has been studied by means of a combined experimental and computational approach. A detailed kinetic profile of the reaction was obtained with respect to consumption of the substrate and formation of the intermediate half‐reduction products, 2,3‐diphenylbut‐1‐ene (2) and the final product, 2,3‐diphenylbutane (3). The data generated from these analyses, and from NMR experiments, revealed several facets of the reaction. After a brief induction period (presumably involving reduction of the cyclooctadiene ligand on C), the diene concentration declines in a zero‐order process primarily to give monoene intermediates. When all the diene is consumed, the reaction accelerates and compound 3 begins to accumulate. Interestingly, the prevalent enantiomer of the monoene intermediate 2 is converted mostly to meso‐3 so the enantioselectivity of the reaction appears to reverse. The reaction seems to be first‐order with respect to the catalyst when the catalyst concentration is less than 0.0075 M; diffusion of hydrogen across the gas–liquid interface complicates the analysis at higher catalyst concentrations. Similarly, these diffusion effects complicated measurements of reaction rate versus applied pressure of dihydrogen; other factors like stir speed and flask geometry come into play under some, but not all, the conditions examined. Density functional theory (DFT) calculations, using the PBE method, were used to probe the reaction. These studies indicate a transoid‐η4‐diene–dihydride complex forms in the first stages of the catalytic cycle. Further reaction requires dissociation of one alkene ligand to give a η2‐diene–dihydride–dihydrogen intermediate. A catalytic cycle that features Ir3+/Ir5+ seems to be involved thereafter.
Synthesis of Phenyl Arylsulfonyl‐alkyl‐dithiocarbamates and Their Hydrolytic Reactivity in Hydroxide and Hydroperoxide Media
Authors: Norberto Fátima , Araújo M. Eduarda M. , Santos Lídia , Jaime Marta S. P. , Mateus Pedro M. V. , Hervés Pablo 
Published: September 2005

AbstractEight previously unreported phenyl arylsulfonyl‐alkyl‐dithiocarbamates were synthesized by treatment of arylsulfonamides with phenyl chlorodithioformate in an adaptation of a general amine acylation method. A kinetic investigation of their alkaline hydrolysis was performed and the experimental data are discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Voltammetric Determination of Surface‐Confined Biomolecules with N‐(2‐Ethyl‐ferrocene)maleimide
Authors: Wang Yunfeng , Zhu Xu , Hu Zhongbo , Wang Jianxiu , Zhou Feimeng 
Published: September 2005

AbstractA thiol‐specific electroactive cross‐linker, N‐(2‐ethyl‐ferrocene)maleimide (Fc‐Mi), has been used to tag surface‐confined peptides containing cysteine residues or oligodeoxynucleotides (ODNs) whose 3′ ends have been modified with thiol groups. The peptides studied herein include both the oxidized and reduced forms of glutathione and a hexapeptide. Cyclic voltammograms (CVs) of the Fc‐Mi groups attached to the surfaces were used to quantify the total number of cysteine residues that are tagged and/or can undergo facile electron transfer reactions with the underlying electrodes. A quartz crystal microbalance was used in conjunction with CV to estimate the total number of cysteine groups labeled by Fc‐Mi per peptide molecule. By comparing to mass spectrometric studies, it is confirmed that not all of the Fc‐Mi linked to the cysteine groups can participate in the electron transfer reactions. The methodology is further extended to the determination of ODN samples in a sandwich assay wherein the thiol linker on the 3′ end can be tagged with Fc‐Mi. The analytical performance was evaluated through determinations of a complementary ODN target and targets with varying numbers of mismatching bases. ODN samples as low as 10 fmol can be detected. Such a low detection level is remarkable considering that no signal amplification scheme is involved in the current method. The approach is shown to be sequence‐ and/or structure‐specific and does not require sophisticated instrumentation and complex experimental procedure.
Matching fusion protein systems for affinity analysis of two interacting families of proteins: the cohesin–dockerin interaction
Authors: Barak Yoav , Handelsman Tal , Nakar David , Mechaly Adva , Lamed Raphael , Shoham Yuval , Bayer Edward A. 
Published: September 2005

AbstractCellulosomes are multi‐enzyme complexes that orchestrate the efficient degradation of cellulose and related plant cell wall polysaccharides. The complex is maintained by the high‐affinity protein–protein interaction between two complementary modules: the cohesin and the dockerin. In order to characterize the interaction between different cohesins and dockerins, we have developed matching fusion‐protein systems, which harbor either the cohesin or the dockerin component. For this purpose, corresponding plasmid cassettes were designed, which encoded for the following carrier proteins: (i) a thermostable xylanase with an appended His‐tag; and (ii) a highly stable cellulose‐binding module (CBM). The resultant xylanase–dockerin and CBM–cohesin fusion products exhibited high expression levels of soluble protein. The expressed, affinity‐purified proteins were extremely stable, and the functionality of the cohesin or dockerin component was retained. The fusion protein system was used to establish a sensitive and reliable, semi‐quantitative enzyme‐linked affinity assay for determining multiple samples of cohesin–dockerin interactions in microtiter plates. A variety of cohesin–dockerin systems, which had been examined previously using other methodologies, were revisited applying the affinity‐based enzyme assay, the results of which served to verify the validity of the approach. Copyright © 2005 John Wiley & Sons, Ltd.