bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the structure and properties of conductive silicone rubber filled with nickel‐coated graphite
Authors: Zou Hua , Zhang Liqun , Tian Ming , Wu Sizhu , Zhao Suhe 
Published: October 2009

AbstractIn this study, the conductive silicone rubber composites filled with nickel‐coated graphite (NCG) have been prepared, and their morphology structure, electrical conductivity, electromagnetic interference shielding efficiency (EMI SE), and mechanical properties have been investigated with reference to the NCG filler loading. The mechanical strength of NCG particle was poor that it can be easily ground into smaller particle during the mixing process if the shear force during mixing is large enough. The electrical conductivity of the composites existed an obvious threshold value with the variation of the loading amount of the conductive filler. EMI SE of the composites increases with the decrease of the volume electrical resistivity. The Payne effect can be used to characterize the intensity of the three‐dimensional conductive network structure in silicone rubber matrix, and the difference of storage modulus in the low and high shear strain has good linear correlation with the electrical conductivity. So, the electrical conductivity and EMI SE can be estimated by means of the difference of storage modulus obtained from rubber process analysis test. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Oxygen barrier coating deposited by novel plasma‐enhanced chemical vapor deposition
Authors: Jiang Juan , Benter Maike , Taboryski Rafael , Bechgaard Klaus 
Published: October 2009

AbstractWe report the use of a novel plasma‐enhanced chemical vapor deposition chamber with coaxial electrode geometry for the SiOx deposition. This novel plasma setup exploits the diffusion of electrons through the inner most electrode to the interior samples space as the major energy source. This configuration enables a gentle treatment of sensitive materials like low‐density polyethylene foils and biodegradable materials. SiOx coatings deposited in the novel setup were compared with other state of the art plasma coatings and were found to possess equally good or better barrier properties. The barrier effect of single‐layer coatings deposited under different reaction conditions was studied. The coating thickness and the carbon content in the coatings were found to be the critical parameters for the barrier property. The novel barrier coating was applied on different polymeric materials, and it increased the barrier property of the modified low‐density polyethylene, polyethylene terephthalate, and polylactide by 96.48%, 99.69%, and 99.25%, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Characterization of polymeric fibers as reinforcements of cement‐based composites
Authors: Jamshidi M. , Karimi M. 
Published: October 2009

AbstractIn this study, three polymeric fibers (nylon 66, polypropylene, and acrylic) were used to improve the flexural and tension strength of cementitious materials. To characterize the performance of these fibers in a cement matrix, scanning electron microscopy, optical microscopy, dynamic mechanical analysis, tensile strength testing, and alkali resistance test were employed. The performance of cement‐based composites containing the fibers was evaluated with a flexural strength test. The results indicated that the flexural strength increased with an increasing number of interfacial interactions between the fibers and cement. This finding was supported by dynamic mechanical analysis data. This has great application potential for fibers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The influence of fiber fineness on physical characteristics of staple polypropylene fibers spun at different pumping speeds
Authors: Zarrebini M. , Mahmoudi M. R. , El‐Bakary M. A. , El‐Dessouky H. M. , Lawrence C. A. 
Published: October 2009

AbstractMelt spinning and pump speed conditions are described for five samples of staple polypropylene PP fibers of different fineness. The influence of fiber fineness or denier on the physical characteristics of staple PP fibers spun at different pump speeds was studied. Optical anisotropy was measured using two‐beam interference microscopy. Enthalpy and degree of crystallinity were measured using differential scanning calorimetry technique for studied fibers. The relation between the fiber diameter, crimp ratio, tenacity, and degree of orientation with the fiber denier are given. A selection of microinterferograms of fibers is given for illustration. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Postconsumer high‐density polyethylene/agave fiber foamed composites coated with chitosan for the removal of heavy metals
Authors: Vázquez M. O. , Herrera V. S. , Gómez C. , Gómez‐Salazar S. , Rodrigue D. , González‐Núñez R. , Luna‐Barcenas J. G. , Mani‐González P. G. , Herrera‐Gomez A. 
Published: October 2009

AbstractComposites of postconsumer high‐density polyethylene with agave fiber were prepared by single‐screw extrusion with azodicarbonamide as a foaming agent to increase the surface area; the composite pellets were coated with chitosan afterward. A chemical pretreatment was applied to the pellets to enhance the chitosan gel compatibility. The adsorption capacities of the composites coated with chitosan were evaluated for Cd(II) and Cu(II) removal from aqueous solutions. The coated composites were characterized by scanning electron microscopy, attenuated total reflectance infrared spectroscopy, and X‐ray photoelectron spectroscopy. Atomic absorption spectroscopy was used to measure metal uptake in batch adsorption studies. The results of this study demonstrated the composites' ability to immobilize chitosan on their surfaces and their capacity to adsorb metal ions. The equilibrium isotherms for Cd(II) and Cu(II) adsorption on the chitosan‐coated composites were described by the Langmuir model. This material represents an attractive low‐cost recycled material for adsorbing metal ions from polluted waters. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis of copper chloride and cobalt chloride doped polyanilines and their magnetic and alternating‐current transport properties
Authors: Gupta K. , Chakraborty G. , Ghatak S. , Jana P. C. , Meikap A. K. 
Published: October 2009

AbstractPolyaniline (PANI) was synthesized by the well‐known oxidative polymerization of aniline with ammonium peroxodisulfate as the oxidant. The morphological, structural, thermal, optical, magnetic, and electrical properties were characterized with scanning electron microscopy, X‐ray diffraction, Fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, ultraviolet–visible spectroscopy, room‐temperature magnetic measurements, and low‐temperature electrical transport measurements by the standard four‐probe method. Greater thermal stability and crystallinity were observed in doped PANI versus pure PANI. Magnetic measurements showed that the magnetic susceptibility was field‐dependent. Positive and negative susceptibility values were observed. This may have been due to the interactions of magnetic ions among interchains or intrachains of the polymer matrix. The alternating‐current (ac) conductivity was measured in the temperature range of 77–300 K in the frequency range of 20 Hz to 1 MHz. The frequency‐dependent real part of the complex ac conductivity was found to follow the universal dielectric response: σ′(f) ∝ fs [where σ′(f) is the frequency‐dependent total conductivity, f is the frequency, and s is the frequency exponent] The trend in the variation of the frequency exponent with temperature corroborated the fact that correlated barrier hopping was the dominant charge‐transport mechanism for PANI–CoCl2. An anomalous dependence on temperature of the frequency exponent was observed for PANI–CuCl2. This anomalous behavior could not be explained in terms of existing theories. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Microstructure and mechanism study of polylactide obtained by the copolymerization of L‐lactide and D,L‐lactide
Authors: Zhao Peng , Wang Qin‐Feng , Zhong Qian , Zhang Nai‐Wen , Ren Jie 
Published: October 2009

AbstractThe stereosequence of polylactide has been analyzed with 13C‐NMR spectroscopy, according to which syndiotactic addition is preferred. According to Markovian statistics, the reactivity ratio, which determines the extent of the syndiotactic stereosequence in the polymer chain, can be calculated by an analysis of the carbonyl and methine regions in the spectra. Moreover, the average lengths of segments SS and RR can be proposed and calculated with the distributing function of the sequence. On this basis, we have investigated the formation mechanism with respect to the preference for the syndiotactic addition of polylactide chains. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation, structural development, and mechanical properties of microfibrillar composite materials based on polyethylene/polyamide 6 oriented blends
Authors: Dencheva Nadya , Oliveira M. Jovita , Carneiro Olga S. , Pouzada António S. , Denchev Zlatan 
Published: October 2009

AbstractThe preparation of microfibrillar composites (MFCs) based on oriented blends of polyamide 6 (PA6) and high‐density polyethylene (HDPE) is described. By means of conventional processing techniques, the PA6 phase was transformed in situ into fibrils with diameters in the upper nanometer range embedded in an isotropic HDPE matrix. Three different composite materials were prepared through the variation of the HDPE/PA6 ratio with and without a compatibilizer: MFCs reinforced by long PA6 fibrils arranged as a unidirectional ply; MFCs containing middle‐length, randomly distributed reinforcing PA6 bristles; and a nonoriented PA6‐reinforced material in which the PA6 phase was globular. The evolution of the morphology in the reinforcing phase (e.g., its visible diameter, length, and aspect ratio) was followed during the various processing stages as a function of the blend composition by means of scanning electron microscopy. Synchrotron X‐ray scattering was used to characterize selected unidirectional ply composites. The presence of transcrystalline HDPE was demonstrated in the shell of the reinforcing PA6 fibrils of the final MFCs. The impact of the compatibilizer content on the average diameter and length of the fibrils was assessed. The influence of the reinforcing phase on the tensile strength and Young's modulus of the various composites was also evaluated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Impact of recreational power boating on two populations of northern map turtles (Graptemys geographica)
Authors: Bulté G. , Carrière M.‐A. , Blouin‐Demers G. 
Published: October 2009

Abstract
Recreational power boating is growing in popularity in North America. This activity is known to have lethal and sub‐lethal effects on aquatic wildlife and freshwater turtles may be particularly sensitive to this activity.
This study reports on patterns of traumatic injuries inflicted by powerboat propellers to northern map turtles (Graptemys geographica) from two sites differing in boat traffic intensity in Ontario, Canada.
The relative vulnerability of turtles was assessed, in light of seasonal patterns in boat traffic, as a function of sex‐ and age‐specific movement patterns, habitat use, and basking behaviour obtained by radio‐telemetry. Population viability analyses (PVA) were also conducted to evaluate the potential demographic consequences of mortality induced by powerboats.
The prevalence of propeller injuries was two to nine times higher in adult females than in adult males and juvenile females. Patterns of movement, habitat use, and aquatic basking indicated that adult females are more exposed to collisions with boats. PVA showed that boat‐induced mortality in adult females could lead to rapid population extinction if the risk of mortality when hit by a boat is greater than 10%.
The results of this study showed that recreational power boating is a serious threat to northern map turtles, even under moderate boat traffic. The need to adopt measures restricting boat traffic in areas important to turtles is discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Safety and efficacy of transradial aortoiliac interventions
Authors: Staniloae Cezar S. , Korabathina Ravikiran , Yu Jennie , Kurian Damian , Coppola John 
Published: October 2009

AbstractBackground: This study compares transradial approach (TRA) aortoiliac angioplasty/stenting to the transfemoral approach (TFA). Methods: We reviewed our peripheral database for aortoiliac interventions performed between 2007 and 2009. Demographics, clinical characteristics, procedural, and lesion details were collected. The efficacy endpoints included procedural success, ankle‐brachial index (ABI) improvement, and time to discharge. The safety endpoints were as follows: occurrence of intra‐/periprocedural complications, 30‐day MACE, and access‐site complications (minor/major). The subjects were divided into two groups, TRA and TFA, and compared using appropriate statistics. Results: Twenty‐seven patients had 33 lesions treated via TRA, and 41 patients had 47 lesions treated via TFA access. Baseline demographic differences between the TRA and TFA groups were similar, including mean Rutherford category (2.9 vs. 2.6, P = 0.31) and preintervention ABI (0.64 vs. 0.67, P = 0.80). There was a significantly higher percentage of total occlusions in the TRA group (27.3 vs. 8.5%, P = 0.03). Dye use (238 vs. 213 mL, P = 0.35) and fluoroscopy time (30 vs. 27 min, P = 0.60) were similar. Procedural success rate was similar (87.9 vs. 97.8%, P = 0.15), as well as the improvement in mean ABI (TRA: 0.64–0.77 and TFA: 0.67–0.85, P = 0.77). The time to discharge was significantly shorter for the TRA group (14.4 vs. 20.9 hr, P = 0.003). There were no 30‐day MACE or major access‐site complications, but minor access‐site complications were lower in the TRA group (0.0 vs. 7.3%, P = 0.28), although nonsignificant. Conclusions: The TRA to aortoiliac interventions is as safe and effective as the TFA with the advantage of a lower rate of access‐site complications and shorter hospitalization time. © 2009 Wiley‐Liss, Inc.
Achieving High Affinity towards a Bacterial Lectin through Multivalent Topological Isomers of Calix[4]arene Glycoconjugates
Authors: Cecioni Samy , Lalor Ruth , Blanchard Bertrand , Praly Jean‐Pierre , Imberty Anne , Matthews Susan E. , Vidal Sébastien 
Published: October 2009

AbstractA family of seven topologically isomeric calix[4]arene glycoconjugates was prepared through the synthesis of a series of alkyne‐derivatised calix[4]arene precursors that are suitable for the attachment of sugar moieties by microwave‐assisted copper(I)‐catalysed azide–alkyne cycloaddition (CuAAC). The glycoconjugates thus synthesised comprised one mono‐functionalised derivative, two 1,2‐ or 1,3‐divalent regioisomers, one trivalent and three tetravalent topoisomers in the cone, partial cone or 1,3‐alternate conformations. The designed glycoconjugates were evaluated as ligands for the galactose‐binding lectin PA‐IL from the opportunistic bacterium Pseudomonas aeruginosa, a major causative agent of lung infections in cystic fibrosis patients. Binding affinities were determined by isothermal titration calorimetry (ITC), and the interaction with the lectin was shown to be strongly dependant on both the valence and the topology. Whereas the trivalent conjugate displayed enhanced affinity when compared to a monosaccharide model, the tetravalent conjugates are to‐date the highest‐affinity ligands measured by ITC. The topologies presenting carbohydrates on both faces of calixarene are the most potent ones with dissociation constants of approximately 200 nM. Molecular modelling suggests that such a multivalent molecule can efficiently chelate two of the binding sites of the tetrameric lectin; this explains the 800‐fold increase of affinity achieved by the tetravalent molecule. Surface plasmon resonance (SPR) experiments confirmed that this glycoconjugate is the strongest inhibitor for binding of PA‐IL to galactosylated surfaces for potential applications as an anti‐adhesive agent.
Linkage Isomerism and Spin Frustration in Heterometallic Rings: Synthesis, Structural Characterization, and Magnetic and EPR Spectroscopic Studies of Cr7Ni, Cr6Ni2, and Cr7Ni2 Rings Templated About Imidazolium Cations
Authors: Boeer Angelika B. , Collison David , Muryn Christopher A. , Timco Grigore A. , Tuna Floriana , Winpenny Richard E. P. 
Published: October 2009

AbstractThe synthesis and structural characterization of three heterometallic rings templated about imidazolium cations is reported. The compounds are [2,4‐DiMe‐ImidH][Cr7NiIIF8(O2CtBu)16] 1 (2,4‐DiMe‐ImidH=the cation of 2,4‐dimethylimidazole), [ImidH]2[Cr6NiII2F8(O2CCtBu)16] 2 (ImidH=the cation of imidazole), and [1‐Bz‐ImidH]2 [Cr7NiII2F9(O2CtBu)18] 3 (1‐Bz‐ImidH=the cation of 1‐benzylimidazole). The structures show the formation of octagonal arrays of metals for 1 and 2 and a nonagon of metal centers for 3. In all cases the edges of the polygon are bridged by a single fluoride and two pivalate ligands, and the position of the divalent metal centers cannot be distinguished by X‐ray diffraction. Magnetic studies combined with EPR spectroscopy allow the characterization of the magnetic states of the compounds. In each case the exchange is antiferromagnetic with a magnetic exchange parameter J≈−5.8 cm−1, and it is not possible to differentiate the exchange between two CrIII centers (JCrCr) from the exchange between a CrIII and a NiII center (JCrNi). For 2 there is evidence for the presence of at least two, possibly four, linkage isomers of the heterometallic ring, caused by the presence of two divalent metal centers in the ring. The EPR spectroscopy of 3 suggests an S=1/2 ground state of the ring and that it is likely that only one linkage isomer is present.
Service‐oriented middleware for financial Monte Carlo simulations on the cell broadband engine
Authors: Rotaru T. , Dalheimer M. , Pfreundt F.‐J. 
Published: October 2009

AbstractFinancial Monte Carlo simulations are computationally intensive applications that must meet tight deadlines in terms of job completion times. The completion time might have a huge impact on the financial profits made from decisions derived from the simulation results. Naturally, there is a huge interest in being able to simulate as fast as possible. While single simulations can be done on one machine, decisions often depend on portfolios of simulations. Distributing the workload among resources is crucial to achieve low latency. In this article we present a combination of a middleware with a high‐performance implementation of an Asian options evaluation code on the Cell Broadband Engine (CBE). We handle workload distribution with our PHASTGrid middleware and provide users with a web service interface to the whole infrastructure. The CBE is particularly suitable for Monte Carlo simulations. We implemented a well‐known algorithm on both the CBE and the Intel x86 multicore architectures. Both codes are integrated in our middleware, allowing a direct comparison of the performance and scalability. In addition to the Monte Carlo simulation, we also use different applications and compare our middleware with Globus. Copyright © 2009 John Wiley & Sons, Ltd.
Graph grammar‐driven parallel partial differential equation solver
Authors: Paszyński Maciej , Schaefer Robert 
Published: October 2009

AbstractThe paper presents an extension of the composite programmable graph grammar (CP‐graph grammar) suitable for modeling the parallel direct solver algorithm utilized by the hp finite element method (hp‐FEM). In the proposed graph grammar model, the computational mesh is represented by a CP‐graph. The presented graph grammar models the solver algorithm by a set of graph grammar productions. The graph grammar model makes it possible to examine the concurrency of the algorithm by analyzing the interdependence between the atomic tasks, tasks and super‐tasks. The atomic tasks correspond to the graph grammar productions, representing basic undividable parts of the algorithms. The level of atomic tasks models the concurrency for the shared memory architectures. On the other hand, the tasks correspond to the groups of atomic tasks with predefined inter‐task communication channels. They constitute the grain for the decomposition of the parallel algorithm for the distributed memory architecture. Finally, the super‐tasks correspond to a group of tasks resulting from the execution of load balancing algorithm. The solver algorithm is tested on distributed memory linux cluster for up to 192 processors. Copyright © 2009 John Wiley & Sons, Ltd.
Is human growth hormone an ergogenic aid?
Authors: Holt Richard I. G. 
Published: October 2009

AbstractGrowth hormone (GH) was first isolated from the pituitary gland in the 1940s. It is believed that athletes have been abusing GH for its anabolic and lipolytic effects since the early 1980s, at least a decade before endocrinologists began to treat adults with GH deficiency. Most of our knowledge about GH abuse is anecdotal but a number of high‐profile athletes have admitted using GH. Despite its widespread abuse, there is debate about whether GH is ergogenic. Indeed most scientific studies have not shown a performance enhancing effect. This review will address why this discrepancy of opinion between athletes and scientists exists and why the author believes that the scientists are wrong. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and Characterization of Gold(I) Complexes with 9‐(4‐Isocyanophenyl)carbazole or 9‐Ethyl‐3‐isocyanocarbazole Ligands
Authors: Benavente Rut , Espinet Pablo , Lentijo Sergio , Martín‐Álvarez Jose M. , Miguel Jesús A. , Paz Rodríguez‐Medina M. 
Published: October 2009

AbstractThe carbazole derivatives 9‐(4‐isocyanophenyl)carbazole, 3,6‐dibromo‐9‐(4‐isocyanophenyl)carbazole, and 9‐ethyl‐3‐isocyanocarbazole were prepared and used to synthesize [AuX(CN‐carbazole)] (X = Cl, C6F5, C6F4‐OEt‐p) gold complexes. The X‐ray structures of [Au(C6F4‐OEt‐p){9‐(4‐isocyanophenyl)carbazole}] and [Au(C6F5)(9‐ethyl‐3‐isocyanocarbazole)], and the luminescent properties of the ligands and the complexes in the solid state, in solution at room temperature, and in frozen solution of chloroform at 77 K were determined. All the gold complexes show a redshift in the emissions relative to that of the free ligand. The presence of electron‐withdrawing substituents in 3,6‐dibromo‐9‐(4‐isocyanophenyl)carbazole quenches the luminescence, but with the introduction of a gold atom some luminescence is recovered.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Grids with Unusual, High Nuclearity – A Structural Approach
Authors: Stadler Adrian‐Mihail 
Published: October 2009

AbstractPolynuclear supramolecular homoleptic grid‐like architectures containing s2 (s = 3, 4, 5) metal ions arranged like the elements of a square matrix and located in the coordination spheres generated at the intersection points (“nodes”) of the 2s bridging s‐topic ligands (the “bars” of the grid), are quite rare, but they are fascinating by their formation by self‐assembly, their structures and properties. Moreover, heteroleptic hexanuclear complete [2 × 3] grids, as well as other kinds of grids containing more than four metal centres were reported. The access to such grids necessitates the design of appropriate polytopic ligands. However, in several cases, incomplete grids were obtained instead of the expected complete grids. The structural diversity of the grids with unusual, high nuclearity reported until now is herein reviewed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)