bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linear convergence of an algorithm for computing the largest eigenvalue of a nonnegative tensor
Authors: Zhang Liping , Qi Liqun 
Published: October 2011

SUMMARYAn iterative method for finding the largest eigenvalue of a nonnegative tensor was proposed by Ng, Qi, and Zhou in 2009. In this paper, we establish an explicit linear convergence rate of the Ng–Qi–Zhou method for essentially positive tensors. Numerical results are given to demonstrate linear convergence of the Ng–Qi–Zhou algorithm for essentially positive tensors. Copyright © 2011 John Wiley & Sons, Ltd.
Preparation and property of 2‐acrylamide‐2‐methylpropanesulfonic acid/acrylamide/sodium styrene sulfonate as fluid loss agent for oil well cement
Authors: Li Huan‐Ming , Zhuang Jia , Liu Han‐Bin , Feng Li , Dong Wenbo 
Published: October 2011

AbstractA novel terpolymer 2‐acrylamide‐2‐methylpropanesulfonic acid/acrylamide/sodium styrene sulfonate (AMPS/AM/SSS), used as fluid loss agent for oil well cement under high temperature, was prepared with initiator of azobisisobutryamide chloride. The optimum reaction conditions of polymerization were obtained from the orthogonal experiments, reaction temperature 40°C, initiator 0.1 wt%, molar ratio of monomers AMPS/AM/SSS 20/5/1. The structure and performance of terpolymer was characterized with Fourier transform infrared spectrometer, nuclear magnetic resonance hydrogen spectrum, thermogravimetric and simultaneous differential thermal analysis, high‐temperature and high‐pressure water loss meter, and rotational viscometer, indicating that the terpolymer was perfectly synthesized and started to decompose at 350°C and showed good performance of fluid loss control up to 160°C. The ζ‐potential instrument and scanning electron microscopy were used to investigate the mechanisms of fluid loss control, indicating that the terpolymer can prevent the generation of flocculated structure in the cement and reduce the porosity of the filter cake. These results have important referential value for developing new high‐temperature‐resisting fluid loss agents. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Tensile properties of microbial β‐glucan films
Authors: Blahovec Jiří , Hejlová Anna , Čopíková Jana , Novák Miroslav 
Published: October 2011

Abstractβ‐glucan films with different plasticizer concentrations (glycerol and water) were deformed in tension and various mechanical characteristics (modulus of elasticity, yield stress, strength, and strain at rupture point) were evaluated. The influence of both plasticizers was of additive nature describable by the total plasticizer content. The influence is reflected by an exponential decrease of either modulus of elasticity or yield stress with increasing total plasticizer content. The film strength decreased linearly with plasticizer concentration, whereas the decline in strain at the rupture point followed a power function. It was also found that the stress parameters can be expressed via modulus of elasticity: the strength as linear function of the square root of the elasticity modulus and the yield stress as a linear function of the latter parameter. On the basis of such relations a quadratic function between strength and yield stress was proposed. This relation well describes the character of the deformation curves that were obtained at different deformation conditions. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Aging property of eco‐friendly anticorrosion organic coating film for telecommunication plant
Authors: Takeshita Yukitoshi , Jackson Richard A. , Sakata Seizou , Sawada Takashi , Nishio Ryuichi 
Published: October 2011

AbstractTelecommunication facilities are protected against long‐term weather exposure by certain prevention technologies. One such technology, namely polymeric materials, is available for coating onto steel or galvanized steel. Physical and chemical aging is an important factor that affects the properties of polymer and, therefore, of coatings. The present study is focused on the effect of aging on the adhesive performance and rheological property of new eco‐friendly anticorrosion organic coating film that we are developing, which has a low volatile organic compound (VOC) content of less than 10%. Exposure to accelerated thermal cycling certainly had an influence on the coating film in that it degraded its adhesive strength and affected the storage modulus and loss tangent. E′ and tan δ were found to evaluate likely planes of failure in multilayer combinations of film. During aging at room temperature, the solvent might evaporate and reach equilibrium. A significant phenomenon was observed, namely that the strengthening effect might relate to the application of tensile stress before the complete evaporation of the solvent. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Liquid crystalline and photocrosslinkable poly(4,4′‐stilbeneoxy) alkylarylphosphates
Authors: Ravikrishnan Angayan , Sudhakara Posa , Kannan Palaninathan 
Published: October 2011

AbstractThree series of liquid crystalline and photocrosslinkable poly(4,4′‐stilbeneoxy) alkylarylphosphates were synthesized from various 4,4′‐bis(m‐hydroxyalkyloxy)stilbenes (m = 2, 4, 6, 8, 10) and arylphosphorodichloridates in chloroform by solution polycondensation method. Polarized optical microscope (POM) and differential scanning calorimetry (DSC) observations revealed that polymers containing less than four methylene spacer groups did not exhibit liquid crystalline (LC) texture, possibly due to smaller microdomain and restricted movement of the mesogen. In contrast, polymers containing more than four methylene spacer group established LC texture, which has been attributed to the larger monodomain and free movement of mesogens. Thermogravimetric analysis (TGA) data indicated that thermal stability and char yield decreased with increasing flexible methylene spacer groups, increased significantly for biphenyloxy and 1‐naphthyloxy containing polymers than that of phenyloxy containing polymers ascribed to increasing aromaticity, size, and number of aromatic rings. Photocrosslinking of stilbene containing polymers has been shown to proceed via 2π‐2π cycloaddition reaction by Ultra‐violet (UV) and fluorescence. The rate photocrosslinking has been found to increase with increasing number of methylene group in the main chain. The aromaticity of the side chain also increases the rate of crosslinking. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Curing of epoxy/carbon nanotubes physical networks
Authors: Chapartegui Maialen , Markaide Nerea , Florez Sonia , Elizetxea Cristina , Fernandez Mercedes , Santamaria Anton 
Published: October 2011

AbstractA melt‐mixing procedure has been used to disperse multi‐walled carbon nanotubes (MWCNT) in an epoxy matrix. According to dynamic viscoelastic results, a physical network is formed for carbon nanotube concentrations of 0.3 weight per cent (wt%) and above. The temperature activated curing process is followed analyzing the evolution of the dynamic viscoelastic functions and the dielectric loss with time. Curing process from a physical to a chemical network is monitored. The presence of MWCNT accelerates curing, even when the rheological percolation is not reached (absence of physical network). Several hypotheses are considered to explain this result. Electrical conductivity decreases during cure, so lower electrical conductivities are found for cured MWCNT/epoxy samples than for dispersions: this is explained by a distortion of nanotubes physical network and a reduction of the ionic conductivity contribution of the liquid phase. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Biaxial deformation and experimental study of PET at conditions applicable to stretch blow molding
Authors: Menary G.H. , Tan C.W. , Harkin‐Jones E.M.A. , Armstrong C.G. , Martin P.J. 
Published: October 2011

AbstractThis article is concerned with understanding the behavior of polyethylene terephthalate (PET) in the injection stretch blow molding (ISBM) process where it is typically biaxially stretched to form bottles for the packaging industry. A comprehensive experimental study was undertaken, analyzing the behavior of three different grades of PET under constant width (CW), simultaneous (EB), and sequential (SQ) equal biaxial deformation. Experiments were carried out at temperature and strain rate ranges of 80–110°C and 1 s−1 to 32 s−1, respectively, to different stretch ratios. Results show that the biaxial deformation behavior of PET exhibits a strong dependency on forming temperature, strain rate, stretch ratio, deformation mode, and molecular weight. The tests were also monitored via a high speed thermal image camera which showed an increase in temperature between 5°C and 15°C depending on the stretch conditions. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Synthesis and characterization of energetic GAP‐b‐PAEMA block copolymer
Authors: Zhang Yang , Zhao Juan , Yang Pan , He Shangjin , Huang Hengjian 
Published: October 2011

AbstractEnergetic block copolymer of polyglycidylazide‐b‐poly (azidoethyl methacrylate) (GAP‐b‐PAEMA) was synthesized and characterized. Macroinitiator PECH‐Br prepared via the reaction of 2‐bromoisobutyryl bromide with hydroxyl‐terminated polyepichlorohydrin (PECH‐OH) was used to initiate the atom transfer radical polymerization (ATRP) of chloroethyl methacrylate (CEMA). After azidation of the resulting copolymer, energetic copolymer GAP‐b‐PAEMA was obtained. Increase in the molecular weight determined by gel permeation chromatograph (GPC) is in agreement with the formation of block copolymer. Fourier transform infrared spectroscopy (FTIR) shows that the chlorine groups in the block copolymer can be substituted by azide group easily. Thermogravimetric analysis (TGA) shows that degradation of GAP‐b‐PAEMA involves two steps: the instantaneous decomposition of the azide groups followed by progressive scission of the polymer backbone. From differential scanning calorimetry (DSC) analysis, the GAP‐b‐PAEMA copolymer exhibits two glass transition temperatures (Tg) at −18 and 36°C, suggesting that the synthesized copolymer is a thermoplastic elastomer. This research provides a new method for the synthesis of energetic polymer. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Characterization of the spatial distribution of irradiance and spectrum in concentrating photovoltaic systems and their effect on multi‐junction solar cells
Authors: Victoria M. , Herrero R. , Domínguez C. , Antón I. , Askins S. , Sala G. 
Published: October 2011

ABSTRACTThe irradiance and spectral distribution cast on the cell by a concentrating photovoltaic system, typically made up of a primary Fresnel lens and a secondary stage optical element, is dependent on many factors, and these distributions in turn influence the electrical performance of the cell. In this paper, the effect of spatial and spectral non‐uniform irradiance distribution on multi‐junction solar cell performance was analyzed using an integrated approach. Irradiance and spectral distributions were obtained by means of ray‐tracing simulation and by direct imaging at a range of cell‐to‐lens distances. At the same positions, I–V curves were measured and compared in order to evaluate non‐uniformity effects on cell performance. The procedure was applied to three different optical systems comprised a Fresnel lens with a secondary optical element consisting of either a pyramid, a dome, or a bare cell. Copyright © 2011 John Wiley & Sons, Ltd.
Unfurling of the band 4.1, ezrin, radixin, moesin (FERM) domain of the merlin tumor suppressor
Authors: Yogesha S. D. , Sharff Andrew J. , Giovannini Marco , Bricogne Gerard , Izard Tina 
Published: October 2011

AbstractThe merlin‐1 tumor suppressor is encoded by the Neurofibromatosis‐2 (Nf2) gene and loss‐of‐function Nf2 mutations lead to nervous system tumors in man and to several tumor types in mice. Merlin is an ERM (ezrin, radixin, moesin) family cytoskeletal protein that interacts with other ERM proteins and with components of cell–cell adherens junctions (AJs). Merlin stabilizes the links of AJs to the actin cytoskeleton. Thus, its loss destabilizes AJs, promoting cell migration and invasion, which in Nf2+/‐ mice leads to highly metastatic tumors. Paradoxically, the “closed” conformation of merlin‐1, where its N‐terminal four‐point‐one, ezrin, radixin, moesin (FERM) domain binds to its C‐terminal tail domain, directs its tumor suppressor functions. Here we report the crystal structure of the human merlin‐1 head domain when crystallized in the presence of its tail domain. Remarkably, unlike other ERM head–tail interactions, this structure suggests that binding of the tail provokes dimerization and dynamic movement and unfurling of the F2 motif of the FERM domain. We conclude the “closed” tumor suppressor conformer of merlin‐1 is in fact an “open” dimer whose functions are disabled by Nf2 mutations that disrupt this architecture.
Longer simulations sample larger subspaces of conformations while maintaining robust mechanisms of motion
Authors: Liu Lin , Gronenborn Angela M. , Bahar Ivet 
Published: October 2011

AbstractRecent studies suggest that protein motions observed in molecular simulations are related to biochemical activities, although the computed time scales do not necessarily match those of the experimentally observed processes. The molecular origin of this conflicting observation is explored here for a test protein, cyanovirin‐N (CV‐N), through a series of molecular dynamics simulations that span a time range of three orders of magnitude up to 0.4 μs. Strikingly, increasing the simulation time leads to an approximately uniform amplification of the motional sizes, while maintaining the same conformational mechanics. Residue fluctuations exhibit amplitudes of 1–2 Å in the nanosecond simulations, whereas their average sizes increase by a factor of 4–5 in the microsecond regime. The mean‐square displacements averaged over all residues (y) exhibit a power law dependence of the form y ∝ x0.26 on the simulation time (x). Essential dynamics analysis of the trajectories, on the other hand, demonstrates that CV‐N has robust preferences to undergo specific types of motions that already can be detected at short simulation times, provided that multiple runs are performed and carefully analyzed. Proteins 2012. © 2011 Wiley Periodicals, Inc.
Electrically detected Rabi oscillations of phosphorus qubits in silicon
Authors: Morley Gavin W. , McCamey Dane R. , Boehme Christoph , van Tol Johan 
Published: October 2011

AbstractElectrically detected magnetic resonance is a sensitive technique for studying electron spins bound to phosphorus atoms in silicon. Using a high magnetic field of 8.6 T increases this sensitivity by accessing a mechanism for spin‐to‐charge conversion which is different to that in the more commonly used magnetic field of ∼0.33 T. The higher‐field regime benefits from a long spin coherence time of over 100 µs because the phosphorus spins that are detected are not coupled to dangling‐bonds. Additionally, the high field permits the spin qubits to reach an equilibrium polarization of over 95% at a temperature of 2.8 K. We demonstrate electrically detected Rabi oscillations of these electron spins in the high‐field regime. The Rabi frequency is proportional to the square root of the excitation power as expected.
Solvation effect on the structural change of a globular protein: A molecular dynamics study
Authors: Mizukami Taku , Saito Hiroaki , Kawamoto Shuhei , Miyakawa Takeshi , Iwayama Masashi , Takasu Masako , Nagao Hidemi 
Published: October 2011

AbstractTo investigate the relationship between structural change and the solvation effect, we estimated the solvation free energy or excess chemical potential (ECP) of a globular protein by the energy representation method for the protein structure obtained by a molecular dynamic simulation. A large fluctuation of ECP was detected. The estimated ECP along the first principal component axis of protein fluctuation was accompanied with “open–close” structural change, which indicated a smooth and progressive change in ECP. By performing a global water density analysis in the grid space, the water density at the hydration site had a strong correlation with the ECP. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
The Burning Rate of Energetic Films of Nanostructured Porous Silicon
Authors: Plummer Andrew , Kuznetsov Valerian , Joyner Timothy , Shapter Joe , Voelcker Nicolas H. 
Published: October 2011

AbstractA systematic study of nanoenergetic films consisting of nanostructured porous silicon impregnated with sodium perchlorate is carried out. The explosive properties of these films are investigated as a function of thickness, porosity, and confinement. The films' burning rates are investigated using fiber‐optic velocity probes, demonstrating that flame‐front velocities vary between approximately 1 and 500 m s−1 and are very sensitive to the films' structural characteristics. Analysis of the flame profile by high‐speed video is also presented, suggesting that the reaction type is a deflagration rather than a detonation. A strong plume of flame is emitted from the surface, indicating the potential for this material to perform useful work either as an initiator or as a propellant. The shape of the flame front transitioned from an inverted V at thin‐film thicknesses to a neat square‐shaped front once the material became self‐confining at 50 μm.
Controlled Synthesis of Tantalum Oxynitride and Nitride Nanoparticles
Authors: Gao Qingsheng , Giordano Cristina , Antonietti Markus 
Published: October 2011

AbstractSynthesis of monodisperse metal nitride and oxynitride nanoparticles with a controllable chemical composition, size, and a well‐defined morphology are useful for applications in fields of catalysis, optoelectronics, and electrochemistry. In this paper a novel method for the controllable synthesis of highly crystalline tantalum oxynitride and nitride nanoparticles with a relatively low polydispersity is presented using urea as the nitrogen source. In the presence of calcium ions as assisting agents, by simply varying the initial urea/Ta molar ratio, both the composition and size of the final product can be tailored to switch from TaON to Ta3N5. The mechanism proposed is that Ca2+ slows down the release of NH3 from the decomposition of urea, which is indispensable for the controllable synthesis of oxynitride and nitride based nanoparticles.
Kainate receptor trafficking
Authors: González‐González Inmaculada M. , Konopacki Filip A. , Rocca Daniel L. , Doherty Andrew J. , Jaafari Nadia , Wilkinson Kevin A. , Henley Jeremy M. 
Published: October 2011

AbstractKainate receptors (KARs) are ligand‐gated ion channels that can regulate neuronal network activity and are involved in processes ranging from neuronal development and differentiation to neurodegeneration and neuronal cell death. They are tetrameric assemblies which can comprise different subunit combinations and are differentially targeted to specific cell surface compartments including pre‐ and postsynaptic membranes where they perform distinct functional roles. The processes regulating the constitutive and activity‐dependent trafficking of KARs are subtle and complex. Intricate combinations of protein–protein interactions and post‐translational modifications orchestrate their surface membrane delivery, residence time, internalization, and recycling or degradation. Furthermore, in addition to regulating surface expression, interacting proteins connect receptors to anchoring and signaling pathways. Although our knowledge of the processes that regulate KAR trafficking is far from complete, there has been significant progress toward defining the roles of many of these protein partners and post‐translational modifications.WIREs Membr Transp Signal2012, 1:31–44. doi: 10.1002/wmts.23For further resources related to this article, please visit theWIREs website.
Drosophila InsP3R mutants and their effects on cellular and systemic physiology
Authors: Agrawal Neha , Hasan Gaiti 
Published: October 2011

AbstractA single gene encoding two identified splice variants of the InsP3R is found in the genome of the fruit fly Drosophila melanogaster. Mutants that perturb InsP3R function differentially have helped identify systemic processes which require the InsP3R. These include larval feeding, larval molting, fluid transport in malpighian tubules, flight circuit development, and olfactory adaptation. Genetic tools that provide spatiotemporal control on overexpression or knockdown of InsP3R in the whole organism have aided in delineating cellular domains that influence these processes. Genetic interaction studies with InsP3R mutants have helped identify several intracellular signaling components that influence InsP3R function. Measurement of their Ca2+dynamics have further revealed a complex interplay between InsP3R‐mediated Ca2+ release, the endoplasmic reticular Ca2+ pump, and components of store‐operated Ca2+ entry (STIM and Orai). Together these players modulate intracellular Ca2+ signals and homeostasis. Changes in cellular Ca2+ signals brought about by altering levels of the identified intracellular Ca2+ signaling components can be correlated with the extent of changes observed in systemic phenotypes. Furthermore, molecular studies of the Drosophila InsP3R have shown that key functional properties of the InsP3R are evolutionarily conserved. Thus, insights gained from Drosophila are likely to be relevant for our understanding of human disorders caused by aberrant InsP3R‐mediated Ca2+ signaling. WIREs Membr Transp Signal 2012, 1:70–77. doi: 10.1002/wmts.7For further resources related to this article, please visit the WIREs website.
mGlu receptors in endocrine organs
Authors: Durand Daniela , Carniglia Lila , Lasaga Mercedes 
Published: October 2011

AbstractMetabotropic glutamate (mGlu) receptors in the central nervous system are known to be essential for neuroplasticity associated with normal brain functions and are also critically involved in various neurological and psychiatric disorders. A recent surge of publications supports the presence, importance, and functionality of mGlu receptors outside the central nervous system with a unique distribution within various tissues. Group I, II, and III mGlu receptors are found in a wide range of peripheral organs including parts of the peripheral nervous system and nonneural organs such as hypophysis, pancreas, adrenal medulla, and the reproductive system. The distinct distribution of mGlu receptors in peripheral tissues is discussed in terms of possible functional endocrine implications. WIREs Membr Transp Signal 2012, 1:78–84. doi: 10.1002/wmts.9For further resources related to this article, please visit the WIREs website.
Framework‐Substituted Bismuth Zeolite‐P: Synthesis and Characterization
Authors: Samadi‐Maybodi Abdolraouf , Naser Azizi Seyed , Masoomeh Pourali S. , Ehsani Tilami Salma 
Published: October 2011

AbstractBismuth‐modified zeolite‐P (Bi‐ZP) was synthesized by hydrothermal methods during the phase transformation of analcime to zeolite‐P. The evolution of phase transformation of pure analcime to Bi‐ZP was investigated. The results showed that bismuth atoms were incorporated into the framework of the microporous zeolite‐P. The effect of various Bi/Al (0–3) and Si/Bi (1–5) mole ratios on the synthesis of bismuth modified zeolite were studied by X‐ray diffraction (XRD) technique and FT‐IR spectroscopy. Evolution of the growth process of Bi‐ZP spheres was carried out at different time intervals with XRD patterns and FE‐SEM images. The energy dispersive X‐ray (EDX) spectrum indicated the existence of bismuth atoms in the synthesized Bi‐ZP. Framework substitutions of bismuth were evidenced by a set of complementary characterizations such as diffusive reflectance UV/Vis (DRS) and Raman spectroscopy on the synthesized Bi‐ZP (Si/Bi = 1).