bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystallization and melting behavior of multi‐walled carbon nanotube‐reinforced nylon‐6 composites
Authors: Phang In Yee , Ma Jianhua , Shen Lu , Liu Tianxi , Zhang Wei‐De 
Published: November 2005

AbstractThe crystallization and melting behavior of neat nylon‐6 (PA6) and multi‐walled carbon nanotubes (MWNTs)/PA6 composites prepared by simple melt‐compounding was comparatively studied. Differential scanning calorimetry (DSC) results show two crystallization exotherms (TCC, 1 and TCC, 2) for PA6/MWNTs composites instead of a single exotherm (TCC, 1) for the neat matrix. The formation of the higher‐temperature exotherm TCC, 2 is closely related to the addition of MWNTs. X‐ray diffraction (XRD) results indicate that only the α‐phase crystalline structure is formed upon incorporating MWNTs into PA6 matrix, independently of the cooling rate and annealing conditions. These observations are significantly different from those for PA6 matrix, where the increase in cooling rate or decrease in annealing temperature results in the crystal transformation from α‐phase to γ‐phase. The crystallization behavior of PA6/MWNTs composites is also significantly different from those reported in PA6/nanoclay systems, probably due to the difference in nanofiller geometry between one‐dimensional MWNTs and two‐dimensional nanoclay platelets. The nucleation sites provided by carbon nanotubes seem to be favorable to the formation of thermodynamically stable α‐phase crystals of PA6. The dominant α‐phase crystals in PA6/MWNTs composites may play an important role in the remarkable enhancement of mechanical properties. Copyright © 2005 Society of Chemical Industry
Synthesis of unimolecular reversed micelle consisting of a poly(L‐lactide) shell and hyperbranched D‐mannan core
Authors: Satoh Toshifumi , Tamaki Masaki , Kitajyo Yoshikazu , Maeda Takahiro , Ishihara Hiroyuki , Imai Tomoko , Kaga Harumi , Kakuchi Toyoji 
Published: November 2005

AbstractA novel biodegradable unimolecular reversed micelle consisting of a poly(L‐lactide) (PLA) shell and a hyperbranched D‐mannan (HBM) core, that is, a chestnut‐shaped polymer (PLA–HBM), was synthesized by the polymerization of L‐lactide on HBM with 4‐(dimethylamino)pyridine (DMAP) as the catalyst. The obtained polymers were soluble in dimethyl sulfoxide, tetrahydrofuran, and chloroform but insoluble in H2O. The molecular weights of the PLA chain on PLA–HBM tended to increase with increasing polymerization time. The number of PLA chains on PLA–HBM could be controlled by the ratio of DMAP to the sugar unit in HBM. The obtained copolymer, PLA–HBM, acted as a unimolecular reversed micelle with an encapsulation ability toward the hydrophilic molecule. In addition, the entrapped hydrophilic molecules were slowly released from the core of PLA–HBM, and the release rate was accelerated by the breaking of the PLA chains of the shell when proteinase K as a hydrolase of PLA was used. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 406–413, 2006
Synthesis and interfacial behaviors of amphiphilic poly(oxypropylene) amidoacids
Authors: Wei Kuan‐Liang , Hung Fei‐Yu , Lin Jiang‐Jen 
Published: November 2005

AbstractA series of hydrophobic poly(oxypropylene) (POP)‐backboned and hydrophilic poly(oxyethylene)‐backboned amidoacids and imidoacids were prepared through the reaction of poly(oxyalkylene) diamines and trimellitic anhydride (TMA) under mild conditions. The synthesized copolymers were characterized with nuclear magnetic resonance and Fourier transform infrared. Their ability to lower the water surface tension and toluene/water interfacial tension was measured and correlated with the hydrophobic/hydrophilic balance with multiple sodium carboxylate functionalities. The specific POP2000/TMA copolymers, consisting of a 2000 g/mol POP segment and multiple amidoacid functionalities, enabled the demonstration of a strong surfactant tendency and a critical micelle concentration at 0.1 wt %. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 646–652, 2006
Syntheses and gas transport properties of polyarylates based on isophthalic and terephthalic acids and mixtures of bisphenol A and 1, 1 bi‐2‐naphthol
Authors: Villegas‐Coss I. , Ruiz‐Treviño F. A. , Hernández‐López S. 
Published: November 2005

AbstractPolyarylates based on isophthalic (IA) and terephthalic (TA) acids and an equimolar mixture of the diols Bisphenol A (BPA) and 1,1 bi‐2‐naphthol (BN) were synthesized to produce BPA‐BN/IA and BPA‐BN/TA polymers and to measure their gas permeability coefficients, P(i), at several pressures and 35 °C, to the gases O2, N2, CH4, and CO2. For the BPA‐BN/IA membranes, at a 2 atm up‐stream pressure, the P(O2) and P(CO2) are 0.93 and 4.0 Barrers with O2/N2 and CO2/CH4 ideal separation factors of 6.7 and 27. For the BPA‐BN/TA, at a 2 atm up‐stream pressure, the P(O2) and P(CO2) are 2.0 and 9.9 Barrers with O2/N2 and CO2/CH4 ideal separation factors of 5.6 and 21. Comparing the selectivity–permeability balance of properties shown by the BPA/TA membranes with that shown by the copolymer BPA‐BN/TA, the balance moves in the direction of higher selectivity and lower permeability because of the incorporation of BN, which is a more rigid monomer than BPA. However, when the balance of properties for the pair O2/N2 shown by BPA‐BN/TA is compared with the one shown by other membranes such as those based on mixtures of diols and diacids, that is the bisphenol A‐naphthalene/I‐T polymers reported in the literature, the balance moves up and to the right of the typical selectivity–permeability trade‐off observed in the BPA‐polyarylate family. Thus, simultaneous incorporations of flexible and rigid monomers in both the diols and the diacids lead to more productive and more selective membranes. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 256–263, 2006
Properties of polystyrene and polymethyl methacrylate copolymers of polyhedral oligomeric silsesquioxanes: A molecular dynamics study
Authors: Patel Reena R. , Mohanraj Rajendran , Pittman Charles U. 
Published: November 2005

AbstractMolecular dynamics simulations were carried out on copolymers of both styrene and methyl methacrylate with polyhedral oligomeric silsesquioxane (POSS) derivatives to identify the origin of the property changes imparted upon the chemical incorporation of POSS. Simulations were carried out on these hybrid copolymers and the parent homopolymers to elucidate the effect of the T8, T10, and T12 POSS cages. These POSS comonomers were derivatized with a single polymerizable function and 7, 9, and 11 nonpolymerizable hydrocarbon moieties, respectively. Glass transition temperatures (Tg) were computed from specific volume versus temperature plots. The packing of POSS units around the polymer backbone was analyzed via their radial distribution functions. The effect of POSS on polymer motion was analyzed through the mean square displacement function. The improvements in the elastic moduli upon incorporation of POSS were computed by employing the static deformation method. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 234–248, 2006
Production of VHF Plasma with Large Area Using a Ladder Shaped Electrode – VHF Plasma Production with Narrow Gap for Solar Cells
Authors: Kawai Yoshinobu , Takeuchi Yoshiaki , Mashima Hiroshi , Yamauchi Yasuhiro , Takatsuka Hiromu 
Published: November 2005

AbstractSummary: VHF H2 and SiH4/H2 plasma was produced using a ladder shaped electrode of 1 200 mm × 141 mm and the plasma parameters were measured with the Langmuir probe. It was found that uniform VHF plasma is achieved over 1 m at a frequency of 60 MHz. VHF plasma was also produced at high pressure. When the pressure was increased from 0.3 Torr to 4 Torr, the plasma density decreased at high pressure, while the electron temperature was around 10 eV at high pressure. Furthermore, Langmuir probe characteristics indicated that there exists a high amount of negative ions at high pressure.Schematic view of the ladder shaped electrode.magnified imageSchematic view of the ladder shaped electrode.
Poly(vinyl alcohol) Desizing Mechanism via Atmospheric Pressure Plasma Exposure
Authors: Matthews Suzanne R. , McCord Marian G. , Bourham Mohamed A. 
Published: November 2005

AbstractSummary: Atmospheric plasma desizing of poly(vinyl alcohol) (PVA) films was investigated using PVA films supplied by MonoSol LLC®. The MonoSol (MS) films were exposed to atmospheric plasma for 0.5 to 5.0 min in thirty‐second increments with additional specimens exposed for 8.0 and 10.0 min durations. Plasma treatment included exposure to helium plasma (He), oxygenated‐helium plasma (He/O2), and helium/carbon tetrafluoride (He/CF4) plasma. The treated films were characterized by weight loss, surface ablation, molecular weight, and solubility. Weight loss data suggested a mechanism of continual ablation, which increases with increased exposure time until saturation. Redeposition of ablated species may take place because the treatment is in a closed‐geometry and thus the saturation trend slightly changes. Thickness changes/surface ablation is in good correlation with the weight loss trends, which suggests that the ablation mechanism is responsible for surface removal. Gel permeation chromatography showed a progressive reduction in the weight‐average molecular weight of the PVA chains with increasing treatment durations. This reduction is attributed to chain‐scission caused by plasma exposure. Solubility tests showed an increase in solubility of plasma‐exposed films in methanol, with a decrease in swelling. These results correlate well with the chain‐scission observed through GPC and weight loss trends.On‐line atmospheric pressure plasma desizing of textile materials.magnified imageOn‐line atmospheric pressure plasma desizing of textile materials.
Transregional Collaborative Research Centre “Fundamentals of Complex Plasmas” Greifswald – Kiel
Authors: Meichsner Juergen 
Published: November 2005

AbstractPlasma News: This section contains news of the plasma community all over the world. Articles about, for example, people, projects, and market trends are welcome. Suggestions should be sent to the editorial office of the Plasma Processes and Polymers, preferably by E‐mail to plasma@wiley‐vch.de. The editorial office decides which articles will be published.
Modelling the effects of alcohol ethoxylates on diffusion of pesticides in the cuticular wax of Chenopodium album leaves
Authors: Burghardt Markus , Friedmann Adrian , Schreiber Lukas , Riederer Markus 
Published: November 2005

AbstractCuticular waxes represent the first and, in most cases, the limiting barrier for foliar uptake of pesticides from solution. Sorption of pesticides in reconstituted cuticular wax (wax/water partition coefficients) of Chenopodium album L. and in isolated cuticular membranes (cuticle/water partition coefficients) of Prunus laurocerasus L. was determined. Diffusion coefficients of pesticides in reconstituted cuticular wax of C. album leaves were size‐dependent, increasing with increasing molar volume. In the presence of alcohol ethoxylates, diffusion coefficients were enhanced by up to two orders of magnitude, and size selectivity was significantly decreased. The accelerating effect and the decrease in size selectivity were attributed to plasticisation of the cuticular wax by the alcohol ethoxylates increasing the fluidity in the wax. A free volume model adopted from polymer science was successfully applied to predict diffusion coefficients of pesticides on the basis of the transport properties of the wax (size selectivity and crystallinity), the molar volume of the diffusing compound and the accelerator concentration in the wax. Copyright © 2005 Society of Chemical Industry
Vulnerability and HIV/AIDS in Africa: from demography to development
Authors: Gould W. T. S. 
Published: November 2005

AbstractGeographical studies of the African HIV/AIDS epidemic must consider not only familiar biological and epidemiological parameters, but also the development contexts in which the epidemic is raging. HIV/AIDS is exceptional in its geographical spread and socio‐economic and demographic impacts: very different from more familiar African diseases such as malaria. Vulnerability to the disease needs to consider not only exposure, but also each society's capacity to cope with it at the same time as the heavy burdens of poverty, prior infection and fragile governance, and also each society's potentiality to intervene to mitigate its potentially devastating effects, whether through facilitating behavioural change or in more effective health provision. The importance of the development dimensions in Africa is illustrated through discussion of the wide range of scenarios offered by UNAIDS for the patterns and levels of the epidemic for 2025. Copyright © 2005 John Wiley & Sons, Ltd.
Mobile vulnerabilities: perspectives on the vulnerabilities of immigrants in the Finnish labour market
Authors: Heikkilä Elli 
Published: November 2005

AbstractIn this article, the types of vulnerability faced by immigrants in the Finnish labour market are investigated in relation to differences in their ethnic origin. Labour‐market performance of immigrants is analysed by local labour‐market area. The most successful immigrants are so‐called Westerners. By contrast immigrants from the developing world face severe problems, especially the fundamental one of getting started in the labour market. High unemployment levels in Finland, the low esteem attributed to foreign work experience by Finnish employers, and inadequate language skills are the main barriers encountered by labour‐market entrants from abroad. There are more jobs for migrants in the major southern cities than in the smaller centres of other regions. Those who are unemployed during the first year after immigration are likely to continue to face problems thereafter. Only a fifth of unemployed immigrants succeeded in finding a job in their first year after arrival year. Copyright © 2005 John Wiley & Sons, Ltd.
The geographies that wound
Authors: Philo Chris 
Published: November 2005

AbstractAs a contribution to debates about vulnerability, this essay is a meditation on the theme of ‘wounds’ and ‘wounding’. The focus is primarily conceptual, reflecting on how vulnerability studies might be recast through the lenses of wounds and wounding, thereby retrieving a critical sense of attributing blame for the ‘making’ of certain peoples and places more vulnerable than others to hazards of all kinds. Emphasis is placed on the interconnected geographies (and histories) through which vectors of blame might be traced, but also on questions arising about how to ‘treat’ the wounds of the vulnerable, touching on more literary–critical and anthropological arguments about how the pain of the wounded should be represented and memorialised. The essay admittedly retreads ground already covered by other critical scholars, but hopefully holds value as part of a broader thrust of progressive ‘ontology‐building’ exercises. Copyright © 2005 John Wiley & Sons, Ltd.
Dielectric nonlinearity of the glassy material Bi1.8Pb0.3Sr2Ca2Cu2.7K0.3Oz
Authors: Gridnev S. A. , Repnikov N. I. 
Published: November 2005

AbstractThe dependence of the dielectric permittivity on the strength of a dc electric field in the glassy dielectric material Bi1.8Pb0.3Sr2Ca2Cu2.7K0.3Oz was studied. It was revealed that the value of the dielectric constant is decreased by a quadratic law as the dc field strength is increased. Such behavior of the dielectric permittivity under external bias electric field speaks in favor of a dielectric nonlinearity, which can be described in frames of a thermodynamic approach. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The influence of magnetic configuration on tunnelling current in double tunnel junctions with ferromagnetic electrodes
Authors: Wilczyński M. , Barnaś J. , Świrkowicz R. 
Published: November 2005

AbstractThe influence of magnetic configuration on tunnelling current in double junctions with ferromagnetic electrodes and nonmagnetic barriers is analysed theoretically in the parabolic electron band model. The calculations are performed in the sequential tunnelling limit. A trapezoidal shape of the barriers is assumed for a biased device. Apart from this, the influence of spin‐flip processes in the central electrode is neglected. The bias voltage dependence of tunnelling current and TMR are calculated numerically. The influence of spin splitting of the electron bands in ferromagnetic electrodes on tunnelling current and TMR is also discussed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the strength of the double exchange and superexchange interactions in La0.67Ca0.33Mn1–yFeyO3 – an NMR and Mössbauer study
Authors: Przewoźnik J. , Kapusta Cz. , Żukrowski J. , Krop K. , Sikora M. , Rybicki D. , Zając D. , Oates C. J. , Riedi P. C. 
Published: November 2005

AbstractA combined study of La0.67Ca0.33Mn0.9757Fe0.03O3 compound by means of zero field 55Mn and 57Fe NMR as well as 57Fe Mössbauer spectroscopy (MS) is reported. The 55Mn NMR spectra exhibit a single double exchange (DE) line up to the magnetic ordering temperature (T C), 200 K, determined from magnetization measurements. The hyperfine field (HFF) remains finite at the T C, which reveals discontinuous character of the transition and the occurrence of a ferromagnetic‐paramagnetic phase segregation. The 57Fe MS HFF decreases much faster with increasing temperature than the 55Mn NMR HFF. Application of a molecular field model to the temperature dependence of the 55Mn and 57Fe HFF allows to estimate values of the Mn–Mn and the Fe–Mn exchange integrals, which amount to 1.24 meV and –0.6 meV, respectively. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic properties of correlated electrons
Authors: Lemański R. 
Published: November 2005

AbstractWe analyze a system composed of itinerant electrons and localized spins with on‐site interactions representing the Hund's first rule. Properties of the system are studied rigorously on the infinite square lattice but the configurational space is restricted to the lowest‐period phases only. Using exact expressions for the ground state energy an evolution of the phase diagram with an external magnetic field is determined. For a wide range of electron densities metamagnetic phase transitions are detected. It is shown that jumps of magnetization of the electrons at the metamagnetic transitions are much smaller than changes of magnetization of the localized spins. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
B3LYP study of the dipole moment and the static dipole (hyper)polarizabilities of para‐nitroaniline in gas phase
Authors: Soscún Humberto , Castellano Olga , Bermúdez Yaneth , Toro Carlos , Cubillán Nestor , Hinchliffe Alan , Phu Xuan Nguyen 
Published: November 2005

AbstractThe dipole moment μ and the electronic (hyper)polarizabilities α, β, and γ tensors of paranitroaniline (PNA) has been calculated in the static regime with the B3LYP hybrid approach of the density functional theory (DFT) formalism and by using the numerical triple finite field method of Kamada et al. The calculations were performed with planar C2v optimized geometry and the standard 6‐31+G(d,p), d optimized 6‐31+G(d*,p) and the specialized Sadlej basis sets. The B3LYP/6‐31+G(d*,p) results of μ, α, β, and γ are comparable to those of the literature. In particular, the static average γ of PNA is comparable to MP2 calculations and is able to reproduce 54% of the experimental static value from Z‐scan experiments recently reported. The origin of the differences between the experimental and theoretical values is discussed. The findings emphasize the use of the DFT methodology in conjunction with optimized basis sets for a reasonable estimated of the electron correlation in static second hyperpolarizability calculations of push–pull conjugated molecules. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Field‐assisted dissociative ionization of CH2I2 induced by femtosecond laser field
Authors: Wang Yan‐Qiu , Zhu Jing‐Yi , Wang Li , Cong Shu‐Lin 
Published: November 2005

AbstractThe field‐assisted dissociative ionization of CH2I irradiated by a 60‐fs 800‐nm laser with different laser intensities (1–4 × 1014 W/cm2) is studied both experimentally and theoretically. The different fragmentation patterns are observed in the experiment with a time‐of‐flight mass spectrometer. In the theoretical aspect, the Gaussian 03 program is applied to calculate the potential energies of CH2I as functions of the CI and CH bond distances and ICI bond angle under external field with different intensities. The calculations explain our experimental observations well. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Theoretical studies on water–tetracaine interaction
Authors: Bernardi R. C. , Gomes D. E. B. , Pascutti P. G. , Ito A. S. , Ota A. T. 
Published: November 2005

AbstractThe action of local anesthetics (LA) is controversial. There is experimental evidence that the unprotonated form of LA penetrates the axon, while the charged form acts in the intracellular phase. To obtain some insight on the structure of the local anesthetics tetracaine and its pharmacological action, we made calculations using the density functional theory (DFT) method. After those calculations, we performed molecular dynamics (MD) simulations in a p, N, T ensemble, in an aqueous environment, on both unprotonated and protonated forms of the molecule. The radial distribution function was used to study water solvent effects, through the characterization of the affinity of tetracaine to water. The results indicate that the molecule has regions with different degree of hydrophobicity, and the N‐terminal of the anesthetic was primarily affected by changes in the protonation state of the anesthetic. The pH‐dependent activity of TTC should then be analyzed in view of local changes in different regions of the molecule, rather than in terms of general effects on the hydrophobicity of the molecule as a whole. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Two‐dimensional correlation spectroscopy techniques applied to ion trap tandem mass spectrometric analysis: nitroaromatics
Authors: Sigman Michael E. , Clark C. Douglas 
Published: November 2005

AbstractThe technique of two‐dimensional (2D) correlation spectroscopy is combined with ion trap tandem mass spectrometric (MS/MS) analysis to provide insight into the energetics and behavior of gas‐phase ions. The 2D correlation method is demonstrated by the analysis of the fragment ions produced by the fragmentation of molecular radical cations of nitrobenzene and m‐nitrotoluene at a series of applied potentials that effect collision‐induced dissociation (CID). The asynchronous correlation intensities show that competitive loss of NO to form [M–NO]+ proceeds at a lower CID energy than loss of NO2 to form [M–NO2]+. The formation of the ion corresponding to [M–NO–CO]+ is shown by the method to occur at a lower CID energy than the formation of [M–NO2]+, but at a higher CID energy than [M–NO]+ for both nitrobenzene and m‐nitrotoluene. Copyright © 2005 John Wiley & Sons, Ltd.