Andrei Ivanov2001-05-07arXiv
In view of the strong anisotropy of oxygen diffusion in high-Tc ceramic YBa2Cu3Ox, it is supposed that a polycrystalline sample of this material can be presented as consisting of crystal grains where each grain was formed by a certain sequence of layers with tetragonal or orthorhombic phase structure. The theory of sc…
Materials ScienceSuperconductivity
G. Colı́、K. K. Bajaj2001-05-07Applied Physics Letters
In this work we present the calculation of the excitonic transition energies in ZnO/MgZnO quantum well heterostructures, accounting for the effects of the exciton–phonon interaction. The results of our calculations clearly show that the description of the electron–hole interaction by means of the static screened Coulo…
ZnO doping and propertiesMagnetic and transport properties of perovskites and related materialsGa2O3 and related materials
Bernd Wölfing、Christian Kloc、Jens Teubner 等 4 位作者2001-05-07Physical Review Letters
$\mathrm{Tl}{}_{9}\mathrm{BiTe}{}_{6}$ exhibits a thermoelectric figure of merit of $\mathrm{ZT}\ensuremath{\sim}1.2$ around 500 K, which significantly exceeds the state-of-the-art materials in this temperature range. The extraordinary thermoelectric performance is mainly due to the extremely low thermal conductivity…
Advanced Thermoelectric Materials and DevicesThermal properties of materialsThermal Expansion and Ionic Conductivity
Wenhui Ma、L. E. Cross2001-05-07OpenAlex
The relationship between elastic strain gradient and electric polarization was investigated in the relaxor ferroelectric lead magnesium niobate ceramic. Experimental studies indicated that flexoelectric polarization is linearly proportional to the applied strain gradient, and the flexoelectric coefficient μ12 is calcu…
Ferroelectric and Piezoelectric MaterialsVibration Control and Rheological FluidsNonlocal and gradient elasticity in micro/nano structures
Bernd Meyer、David Vanderbilt2001-05-07arXiv
For the ferroelectric perovskite compounds ${\mathrm{BaTiO}}_{3}$ and ${\mathrm{PbTiO}}_{3},$ we have studied the effects of external electric fields on the structural properties of the (001) surfaces. The field-induced changes in the surface interlayer spacings and bucklings have been calculated using a first-princip…
Ferroelectric and Piezoelectric MaterialsAcoustic Wave Resonator TechnologiesElectronic and Structural Properties of Oxides
Wenjie Chen、D. J. David、William J. MacKnight 等 4 位作者2001-05-05Macromolecules
The miscibility and phase behavior in blends of poly(vinyl butyral) (PVB) and atactic poly(methyl methacrylate) (PMMA) were studied by dynamical mechanical thermal analysis (DMTA) and optical microscopy (OM). PVB is regarded as a random copolymer containing vinyl butyral (VB) and vinyl alcohol (VA) units. In this stud…
Polymer crystallization and propertiesMaterial Dynamics and PropertiesRheology and Fluid Dynamics Studies
Hironori Hondoh、Gen Sazaki、Satoru Miyashita 等 6 位作者2001-05-05Crystal Growth & Design
Intermolecular contacts in crystals of monoclinic form hen egg-white lysozyme were analyzed using the macrobond approach. Both the macroscopic crystal morphology and the microscopic morphology observed by atomic force microscopy were explained well using macrobond energies. The features of the advancing steps of the g…
Enzyme Structure and FunctionCrystallization and Solubility Studiesnanoparticles nucleation surface interactions
Rakchart Traiphol、Hiren V. Shah、Dennis W. Smith 等 4 位作者2001-05-05Macromolecules
This study introduces the phase diagram and interfacial characteristics of a novel lyotropic polymeric liquid crystal. The polymer consists of an α-methylstilbene mesogenic group bridged by a low interfacial energy perfluorocyclobutyl ring via flexible aryl ether linkages. The polymer, obtained by thermal cyclopolymer…
Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsBlock Copolymer Self-Assembly
Rittirong Pruthtikul、Michael M. Coleman、Paul C. Painter 等 4 位作者2001-05-05Macromolecules
We have previously shown that infrared spectroscopy can be used to “count” the number of contacts in hydrogen-bonded system. We use such information to determine appropriate self- and interassociation equilibrium constant values and at the same time take into account the intramolecular “screening” in polymer blends an…
Advanced Polymer Synthesis and CharacterizationPolymer Surface Interaction StudiesDendrimers and Hyperbranched Polymers
Rédouane Borsali、Sébastien Lecommandoux、R. Pecora 等 4 位作者2001-05-05Macromolecules
Static and dynamic scattering properties of (a−b) diblock copolymer chains having different architectures are discussed in the framework of the random phase approximation (RPA). The case of a symmetric diblock (50/50) in a solvent satisfying the zero average contrast condition, in the semidilute regime, is considered…
Advanced Polymer Synthesis and CharacterizationRheology and Fluid Dynamics StudiesBlock Copolymer Self-Assembly
Kenji Miyatake、Antisar R. Hlil、Allan S. Hay2001-05-05Macromolecules
ADVERTISEMENT RETURN TO ISSUEPREVNoteHigh Molecular Weight Aromatic Polyformals Free of Macrocyclic Oligomers. A Condensative Chain Polymerization ReactionKenji Miyatake, Antisar R. Hlil, and Allan S. HayView Author Information Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal, Quebec H3A 2K6…
Advanced Polymer Synthesis and CharacterizationInorganic and Organometallic ChemistrySynthesis and properties of polymers
Min Wei、Alan E. Tonelli2001-05-05Macromolecules
We have found, when inherently immiscible polymers are included as guests in the narrow channels of their common inclusion compounds (ICs) formed with host cyclodextrins (CDs) and then these polymer-1/polymer-2-CD-IC crystals are washed with hot water to remove the host CD lattice and coalesce the guest polymers, that…
Polymer crystallization and propertiesAdvanced Polymer Synthesis and Characterizationbiodegradable polymer synthesis and properties
Hitoshi Sashiwa、Yoshihiro Shigemasa、René Roy2001-05-05Macromolecules
Sialic acid dendrons bearing a focal aldehyde end group were synthesized by a reiterative amide bond strategy. Polyamine-ending trivalent ( G = 1) and nonavalent ( G = 2) dendrons having gallic acid as branching unit and tri(ethylene glycol) as spacer arm were prepared and initially attached to a sialic acid p- phenyl…
Chemical Synthesis and AnalysisSynthetic Organic Chemistry MethodsDendrimers and Hyperbranched Polymers
Shiao‐Wei Kuo、Feng Chang2001-05-05Macromolecules
Blends of poly(vinylphenol- co -methyl methacrylate) (PVPh- co -PMMA) with poly(ethylene oxide) (PEO) were prepared by solution casting from tetrahydrofuran (THF) solution. The miscibility behavior and hydrogen bonding of blends were investigated by differential scanning calorimetry (DSC), Fourier transform infrared s…
Polymer crystallization and propertiesAdvanced Polymer Synthesis and CharacterizationPolymer Nanocomposites and Properties
David L. VanderHart、Atsushi Asano、Jeffery W. Gilman2001-05-05Macromolecules
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTNMR Measurements Related to Clay-Dispersion Quality and Organic-Modifier Stability in Nylon-6/Clay NanocompositesD. L. VanderHart, A. Asano, and J. W. GilmanView Author Information Polymers Division, Mailstop 8544, National Institut…
Polymer crystallization and propertiesPolymer Nanocomposites and PropertiesClay minerals and soil interactions
Arlette R. C. Baljon、Mark O. Robbins2001-05-05Macromolecules
Craze formation determines the effective strength of many structural polymers and glassy polymer adhesives. We use molecular dynamics simulations to study the evolution of craze formation in glassy polymers as the number of monomers per chain N increases. When N is less than the entanglement length N e, the polymer ca…
Polymer crystallization and propertiesMaterial Dynamics and PropertiesRheology and Fluid Dynamics Studies
Keiran Fleming、Derek G. Gray、Stephen Matthews2001-05-04Chemistry - A European Journal
This article discusses advances in understanding the structural and physicochemical characteristics of suspensions of cellulose crystallites prepared by acid hydrolysis of natural cellulose fibres. Consideration of recent developments in visualization of crystallite ultrastructure may provide clues to suspension behav…
Advanced Cellulose Research Studies
Rong Yang、Y M Wang、H Q Ye 等 4 位作者2001-05-04Journal of Physics Condensed Matter
A scheme to evaluate the Griffith work of interfacial separation, 2γ int , is proposed based on first principles to investigate the segregation effects on a Σ11[1 0]/(11 ) γ-iron grain boundary. The chemical interaction of substitutional segregants Cr and Mn is able to enhance the cohesion of the grain boundary by ani…
Microstructure and mechanical propertiesFusion materials and technologiesCopper Interconnects and Reliability
Qing Jiang、Lihong Liang、Ming‐Chun Zhao2001-05-04Journal of Physics Condensed Matter
The melting temperature of nano-ice confined in micropores of MCM-41 is predicted by use of our simple model based on the Lindemann criterion. The model takes into consideration the density of the OH bonds of MCM-41 pores; its prediction is consistent with the experimental results for the melting temperature of nano-i…
Carbon Nanotubes in CompositesZeolite Catalysis and SynthesisMaterial Dynamics and Properties
Dario Pisignano、S. Capaccioli、R. Casalini 等 7 位作者2001-05-04Journal of Physics Condensed Matter
Study of the relaxation behaviour of a tri-epoxy compound in the supercooled and glassy state by broadband dielectric spectroscopy, D Pisignano, S Capaccioli, R Casalini, M Lucchesi, P A Rolla, A Justl, E Rössler
Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesPolymer Nanocomposites and Properties