bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ring‐opening polymerization of 1‐methyltrimethylene carbonate by rare earth initiators
Authors: Ling Jun , Dai Yongbo , Zhu Yinghong , Sun Weilin , Shen Zhiquan 
Published: July 2010

AbstractRing‐opening polymerization of 1‐methyltrimethylene carbonate (MTMC) initiated by highly active single‐component rare earth tris(2,6‐di‐tert‐butyl‐4‐methylphenolate)s [Ln(OAr)3, Ln = La, Dy, Y] or yttrium isopropoxide [Y(OiPr)3] is reported for the first time. PolyMTMC (Mw = 8.4 × 104, molecular weight distributions = 1.5) initiated by La(OAr)3 at [MTMC]/[initiator] = 1000 was obtained with the yield over 99% in toluene within 1 h at 30 °C. Random and block copolymers of MTMC with ε‐caprolactone (CL), 2,2‐dimethyltrimethylene carbonate (DTC) or polyethylene glycol (PEG) including poly(MTMC‐r‐CL), poly(MTMC‐b‐CL), poly(MTMC‐r‐DTC), poly(MTMC‐b‐DTC), and poly(MTMC‐b‐PEG‐b‐MTMC) were synthesized. The differential scanning calorimetry results show that thermal behaviors of the polymers sensitively depend on their compositions and chain structures. Furthermore, the measurements of 1H‐1H COSY and density functional theory calculation are applied to investigate the mechanism. The polymerization of MTMC takes place according to a coordination‐insertion mechanism, and the ring is opened via acyl‐oxygen bond cleavage resulting in a LnO active center. There exist two ring‐opening modes of MTMC in which mode b, breaking the CH2OCO bond, is the major pathway. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3807–3815, 2010
Highly efficient and stable blue‐light‐emitting binaphthol‐fluorene copolymers: A joint experimental and theoretical study of the main‐chain chirality
Authors: An Zhongfu , Yin Jun , Shi Naien , Jiang Hongji , Chen Runfeng , Shi Huifang , Huang Wei 
Published: July 2010

AbstractIn a quest for the main‐chain chiral and highly stable blue‐light‐emitting π‐conjugated polymers, a novel series of soluble conjugated random and alternating copolymers (PF‐BN) derived from fluorene and axially chiral 1,1′‐binaphthol (BINOL) were successfully synthesized by Suzuki coupling polymerization. The polymer structures, optical properties, and their electrochemical properties were investigated by 1H NMR, TGA/DSC, UV‐Vis absorption, photoluminescence, cyclic voltammetry, circular dichroism spectroscopy, and DFT calculations. The blue‐light‐emitting BINOL‐containing copolymers with proper content of BINOL show highly efficient photoluminescence and ultra highly stable light‐emission with almost unchanged fluorescent spectra after annealing at 200 °C in air for 10 h. The joint experimental and theoretical study of the main‐chain chirality reveals that (1) the chirality of BINOL can be transferred to the polymer backbone, (2) the effective conjugation length is about one BINOL and three fluorenes, (3) the main active chiral block in the copolymers is probably composed by one BINOL with the other two or three fluorenes, and (4) the dihedral angle in the PF‐BN copolymers should be larger than 105°. The incorporation of BINOL into the polyfluorene backbone is an effective way to produce highly efficient and stable blue‐light‐emitting main‐chain chiral conjugated polymer with interesting optoelectronic properties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3868–3879, 2010
A versatile surfactant‐mediated synthetic route to gold/polyaniline derivative core/shell nanocomposites
Authors: Han Jie , Liu Yan , Wang Lu , Guo Rong 
Published: July 2010

AbstractThis article describes a versatile two‐step method for gold/polyaniline derivative core/shell nanocomposites with the aid of nonionic surfactant F127. First, F127 and monomer were introduced to gold colloids followed by the addition of oxidant to initiate the polymerization of monomer to afford a conducting polymer shell around each gold nanoparticle. Experimental parameters, such as kinds and concentrations of surfactant and monomer, gold core size and shape, reaction time, were systematically investigated to disclose the underground mechanisms involved in the formation of gold/polymer core/shell nanocomposites. Furthermore, Fourier transform infrared, ultraviolet–visible, X‐ray diffraction, and X‐ray photoelectron spectroscopy techniques were used to characterize the gold/polymer core/shell nanocomposites. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3903–3912, 2010
Structural development of ultra‐high strength polyethylene fibers: Transformation from kebabs to shishs through hot‐drawing process of gel‐spun fibers
Authors: Ohta Yasuo , Murase Hiroki , Hashimoto Takeji 
Published: July 2010

AbstractStructural development of ultra‐high strength polyethylene fibers via hot‐drawing processes of as‐spun gel fibers was investigated by means of transmission electron microscopy. It is found that the shish‐kebabs developed in both the as‐spun and drawn fibers can be transformed continuously into the micro‐fibril structure composed mostly of the shish structure through the hot‐drawing process. The structure transformation involves a drastic decrease in diameter of the kebab plus the shish but almost no change in the shish diameter. This result suggests that the chains in the kebabs are incorporated into the shishs and consumed to extend the longitudinal dimension of the shishs during the drawing process. The proposed new deformation model well explains the relationship between the fiber morphology and their mechanical properties: the tensile strength and modulus of the fibers can be determined by the number of the shish in the fiber and the macroscopic diameter of the fiber, which are apriori determined at the spinning process. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1861–1872, 2010
Effects of magnetic field on shear stress of nematic liquid crystalline polymer under simple shear flow
Authors: Fu Shu.‐F. , Wang Xuan‐zhang 
Published: July 2010

AbstractThe effect of magnetic fields on the shear stress of liquid crystalline polymers (LCPs) under shear flows is numerically analyzed using the Doi theory. The evolution equation for the probability density of LCP molecules is directly solved without any closure approximations. When the magnetic field is imposed on the LCPs along the shear flow, the low‐shear rate plateau of the time‐averaged generalized viscosity
$ \bar{\eta}^*(=\bar\sigma_{xy}^{*}/\dot\gamma^{*}) $
disappears, which is due to the manner of the new aligning mode observed by Fu et al. The negative first normal stress difference
$ \bar N_{1}^{*} $
becomes opposite in all the shear rate regimes with the disappearance of periodic oscillations. For the magnetic field parallel to the velocity gradient direction, the more complicated sign changes of
$ \bar N_{1}^{*} $
is investigated because of the moment caused by the magnetic field vertical to the one caused by the shear flow. The ratio
$ \bar N_{2}^{*}/\bar N_{1}^{*} $
increases with the increasing magnetic field strength. Finally, when the molecular shape parameter is considered as 0.9, the similar discussions are achieved according to the phase diagram among tumbling, wagging, and aligning modes versus the magnetic field strength. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1919–1926, 2010
Isothermal crystallization kinetics of polypropylene latex–based nanocomposites with organo‐modified clay
Authors: Raka Luljeta , Sorrentino Andrea , Bogoeva‐Gaceva Gordana 
Published: July 2010

AbstractThe effect of organo‐modified clay (Cloisite 93A) on the crystal structure and isothermal crystallization behavior of isotactic polypropylene (iPP) in iPP/clay nanocomposites prepared by latex technology was investigated by wide angle X‐ray diffraction, differential scanning calorimetry and polarized optical microscopy. The X‐ray diffraction results indicated that the higher clay loading promotes the formation of the β‐phase crystallites, as evidenced by the appearance of a new peak corresponding to the (300) reflection of β‐iPP. Analysis of the isothermal crystallization showed that the PP nanocomposite (1% C93A) exhibited higher crystallization rates than the neat PP. The unfilled iPP matrix and nanocomposites clearly shows double melting behavior; the shape of the melting transition progressively changes toward single melting with increasing crystallization temperature. The fold surface free energy (σe) of polymer chains in the nanocomposites was lower than that in the PP latex (PPL). It should be reasonable to treat C93A as a good nucleating agent for the crystallization of PPL, which plays a determinant effect on the reduction in σe during the isothermal crystallization of the nanocomposites. The activation energy, ΔEa, decreased with the incorporation of clay nanoparticles into the matrix, which in turn indicates that the nucleation process is facilitated by the presence of clay. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1927–1938, 2010
HRTEM observation of defect structures of β‐Ga2O3nanowires
Authors: Yang Qing , Yasuda Takahiro , Brown Paul D. , Tanaka Miyoko , Tatsuoka Hirokazu 
Published: July 2010

AbstractThe defect structures of β‐Ga2O3nanowires were characterized using transmission electron microscopy (TEM). Branched and jagged β‐Ga2O3nanowires were obtained by the heat treatment of gallium metal with Cu5Si powders. The growth direction of the branched nanowire is perpendicular to the (001) planes, the (001) planes of the branch nanowire, and the (110) planes of the primary nanowire face each other at the grain boundary. The jagged nanowire has a growth direction combining the [001] and$[\bar {1}01]$directions. Cu atoms were highly concentrated at the β‐Ga2O3nanowires, and the effect of impurity on the growth of β‐Ga2O3nanowires was demonstrated. The dynamic evolution of β‐Ga2O3nanowires with reference to specific morphological features was discussed in terms of the anisotropic crystalline structures of the β‐Ga2O3crystals. It is found that the structural and morphological properties of β‐Ga2O3nanowires were greatly influenced by the growth conditions, and the specific crystalline defects affected the final morphological feature of the nanowires.
Structural and magnetic characterizations of MnNiZn ferrite nanoparticles
Authors: Mane Dhanraj R. , Birajdar Damodar D. , Shirsath Sagar E. , Telugu Raghavender A. , Kadam Ram. H. 
Published: July 2010

AbstractThe ferrite samples of Ni0.7−xMnxZn0.3Fe2O4 (where x = 0.0–0.7 in steps of x = 0.1) were synthesized by a sol–gel autocombustion method using nitrates of respective metal ions. The synthesized samples were annealed at 600 °C for 4 h. The phase purity of the samples was investigated by X‐ray diffraction (XRD). An analysis of XRD patterns reveals the formation of single‐phase cubic spinel structure. The crystal lattice constant increases gradually with increasing x from 8.389 to 8.473 Å. The cation distribution of constituent ions shows linear dependence of Mn substitution. Based on the cation distribution obtained from XRD data, structural parameters such as lattice parameters, ionic radii of available sites, and the oxygen parameter “u” have been calculated. The trend of theoretically calculated lattice parameter with Mn content matches well with the experimentally obtained values. An initial increase followed by a subsequent decrease of saturation magnetization with increase in x is observed. Possible explanations for the observed structural and magnetic behavior with various Mn content are discussed.
Electrodeposition of transparent and conducting graphene/carbon nanotube thin films
Authors: Bittolo Bon S. , Valentini L. , Kenny J. M. , Peponi L. , Verdejo R. , Lopez‐Manchado M. A. 
Published: July 2010

AbstractWe report the electrophoretic deposition of graphene/single‐walled carbon nanotube hybrid films onto flexible, transparent and conducting indium tin‐oxide‐coated polyethylene terephthalate substrates. This room‐temperature solution process is completely compatible with polymeric substrates and does not require a sophisticated transfer process, allowing uniform and controllable deposition of such carbon thin films with tailored optical and electrical properties over large areas. In particular, the film thickness, optical transparency and electrical conductivity can be modified by the deposition time and the obtained films span several square centimetres in area.
Design of a hierarchical structure of ZnO by electrochemistry for ZnO‐based dye‐sensitized solar cells
Authors: Haller Servane , Suguira Takashi , Lincot Daniel , Yoshida Tsukasa 
Published: July 2010

AbstractA hierarchical structure with a large surface area and an efficient carrier transfer of the electrons has been developed. This structure is composed of zinc oxide nanorods surrounded by nanoporous zinc oxide and is obtained by a two‐step cathodic electrodeposition. Different geometries could be identified whether the hierarchical structures have grown enough to join themselves or not. The first moments of the electrodeposition of the nanoporous structure on the nanorods have been investigated and it is revealed that a nanoporous layer is epitaxially deposited. Preliminary tests of dye‐sensitized solar cell were prepared with this structure that confirmed the interest of the concept.magnified image
Schematic figure of principle.
GaN‐based ultraviolet light‐emitting diodes with multifinger contacts
Authors: Rodríguez Hernán , Lobo Neysha , Einfeldt Sven , Knauer Arne , Weyers Markus , Kneissl Michael 
Published: July 2010

AbstractGaN‐based ultraviolet light‐emitting diodes with identical contact areas but different contact shapes are studied. Interdigitated multifinger contacts with reduced finger width result in a lower series resistance and a thermal roll‐over of the output power at higher cw currents in comparison to square‐shaped contacts. Under pulsed operation, the external quantum efficiency in these devices is increased due to a reduction of the efficiency droop at elevated currents. Simulations of the current distribution explain the experimental data with an improved uniformity of the current density in multifinger contacts as current crowding at the contact edges is largely suppressed.
Reactions on the SiC(0001) √3 × √3 R30° surface after Ti deposition and annealing
Authors: Johansson L. I. , Virojanadara C. 
Published: July 2010

AbstractThe interactions of thin Ti layers deposited on the SiC(0001) √3 × √3 R30° surface at room temperature and after annealing at temperatures from 450 to 1200 °C was investigated using photoemission and LEED. Chemically shifted components were revealed in the Si 2p spectrum and found to be more intense and pronounced than the shifted component in the C 1s spectrum after Ti deposition and annealing. The relative intensity of these shifted components were found to increase initially upon annealing at temperatures up to around 700 °C. At temperatures above 800 °C only the shifted component in the C 1s spectrum remained which indicate that only TiC then remains on the surface. At annealing temperatures of 600–700 °C formation of the ternary Ti3SiC2 phase and an interface TiSix layer is suggested from shifts and relative intensities observed for these components. That the formation and decomposition of the ternary phase occurs at a considerably lower temperature than earlier reported is attributed to the fact that we investigated the interaction of considerably thinner Ti layers with SiC substrates than in those earlier reported studies.
A bibliography of the literature on process capability indices: 2000–2009
Authors: Yum Bong‐Jin , Kim Kwan‐Woo 
Published: July 2010

AbstractThis paper contains a bibliography of approximately 530 journal papers and books on process capability indices for the period 2000–2009. The related literature is classified into four major categories, namely, books, review/overview papers, theory‐ and method‐related papers, and special applications. Theory‐ and method‐related papers are further classified into univariate and multivariate cases, and special applications include acceptance sampling plans, supplier selection, and tolerance design and other optimizations. Copyright © 2010 John Wiley & Sons, Ltd.
The development of a robust design methodology for time‐oriented dynamic quality characteristics with a target profile
Authors: Goethals Paul L. , Cho Byung Rae 
Published: July 2010

AbstractInnovative engineering techniques are often sought within the manufacturing environment to improve product quality and promote more cost‐effective strategies. Robust design methods are frequently used to serve this purpose, with the objective of minimizing the variability inherent within a particular process or system. A review of the literature suggests that most robust design research involves the study of static quality characteristics, given a pre‐defined specification interval or region and target value. In addition to proposing a methodology for working with dynamic quality characteristics where the specifications and target value may change over time, this paper offers two other distinct contributions. First, those researchers who have examined dynamic systems traditionally consider the effects of a signal factor on a response variable on the identification of optimal factor settings. In contrast, this paper will consider the effects of a quality characteristic changing over time, thus removing the need to confine the problem to signal–response systems. Furthermore, most researchers consider the optimization of the process mean according to the costs of non‐conforming to an established specification interval or region. This paper, however, utilizes a methodology involving the simultaneous optimization of the process mean and variance while expanding the problem to consider a loss in quality attributed to deviation from a target value over time. Copyright © 2010 John Wiley & Sons, Ltd.
Unconventional H‐bonds: SH···N interaction
Authors: Solimannejad Mohammad , Scheiner Steve 
Published: July 2010

AbstractQuantum calculations at the MP2/aug‐cc‐pVDZ level are used to analyze the SH···N H‐bond in complexes pairing H2S and SH radical with NH3, N(CH3)3, NH2NH2, and NH2N(CH3)2. Complexes form nearly linear H‐bonds in which the SH covalent bond elongates and shifts its stretching frequency to the red. Binding energies vary from 14 kJ/mol for acceptor NH3to a maximum of 22 kJ/mol for N(CH3)3and N(CH3)2NH2. Analysis of geometric, vibrational, and electronic data indicate that the SH···N interaction involving SH is slightly stronger than that in which the closed‐shell H2S serves as donor. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Managing municipal solid waste from a system perspective: A comparative study of Dalian, China and Waterloo, Canada
Authors: Chen Xudong , Haight Murray E. , Geng Yong , Fujita Tsuyoshi 
Published: July 2010

AbstractIn China, one of the challenges on managing solid wastes is how to realize waste reduction, reuse and recycling while maintaining rapid development, leading to a demand for an Integrated Solid Waste Management (ISWM) approach. A practical way to improve ISWM in developing countries is to learn from successful experiences in developed countries. Hence, systematic comparisons that reflect the complexity of ISWM systems in different contexts are needed. This paper takes a system perspective to compare and contrast two cases, the Region of Waterloo in Canada and Dalian in China, exploring the reasons for the different management approaches between the two cases. The results show that in some aspects, differences between the two waste management systems are tightly linked to their respective social and economic contexts, which can hardly be changed, whereas other differences can be attributed mainly to management strategies and tools. Suggestions are provided on waste planning, the development of waste diversion programs and waste treatment industries, the design of new programs, and the role of the local government. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Sustainable consumption: Green purchasing behaviours of urban residents in China
Authors: Liu Xianbing , Wang Can , Shishime Tomohiro , Fujitsuka Tetsuro 
Published: July 2010

ABSTRACTGreen purchasing (GP) is an important part of sustainable consumption, which reduces the impact of society on the environment. As few studies of people's GP behaviours exist for China, this paper tries to close the gap by exploring GP behaviours of urban residents in Suzhou city, Jiangsu Province. A total of 336 valid samples in a questionnaire survey are used for the analysis. Nearly half of the respondents have seldom bought green products, confirming a low level of residential GP practices. The path analysis clarifies the cause and effect linkages between the predicting variables and GP behaviours. Environmental attitudes, especially perception of self‐responsibility, greatly influence intention of GP behaviours. The available information of green products significantly determines people's actual GP behaviours. This study addresses the importance of environmental education in enhancing the public's environmental responsibility in China. More information on green products should be distributed to assist in GP practices of consumers. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Food miles to assess sustainability: A revision
Authors: Van Passel Steven 
Published: July 2010

ABSTRACTSustainability assessment is an essential process in our aim to reach a more sustainable production and consumption pattern. This research revises the food miles concept as a guiding tool to assess sustainability. Food miles measure the distance that food travels from where it is grown or raised to where it is consumed. Three different concepts to assess sustainability are described: (i) food miles, (ii) enhanced food miles, (iii) food chain sustainability. An illustrative case study shows that there is a strong danger of oversimplification when using food miles as an assessment tool. Second, the food miles concept can be enhanced with all relevant transport externalities taking into account different transport modes and transport (in)efficiency. Third, all relevant economic, social, and ecological aspects should be taken into account. Besides transport externalities, also externalities caused by food production, food packaging, food marketing, and food consumption should be incorporated. Moreover, the trade‐off with development goals cannot be neglected. As a consequence, there is a strong danger of incommensurability as the result of different sustainability model assumptions and unclear system boundaries. Nevertheless, sustainability assessment can enrich policy making and support tailored policy measures to improve food chain sustainability. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Digital credentials with privacy‐preserving delegation
Authors: Knox D. A. , Adams C. 
Published: July 2010

AbstractThis paper extends digital credentials, a cryptographic scheme that provides provably secure, private, attribute certificates. We give a method for the delegation of these credentials, which allows the delegator to reveal a subset of his/her credentials to a delegatee, who in turn can control revelation of this subset to a verifier. Our method also supports blinded showing of credentials to a specified verifier in order to hide the credentials from the delegatee, when desired. Privacy is preserved in all cases under a strong attack model that includes collusion between an attacker (Malice) and the Certification Authority that issued the credentials. Copyright © 2010 John Wiley & Sons, Ltd.