S. Kubota、Yuugo Suzuyama、Hisanori Yamane 等 4 位作者1998-07-14ChemInform
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” opt…
Nuclear materials and radiation effectsLuminescence Properties of Advanced MaterialsMicrowave Dielectric Ceramics Synthesis
V. A. Osipov、S. E. Krasavin1998-07-14arXiv
The problem of phonon scattering by grain boundaries is studied within the wedge disclination dipole (WDD) model. It is shown that a specific q-dependence of the phonon mean free path for biaxial WDD results in a low-temperature crossover of the thermal conductivity, $κ$. The obtained results allow to explain the expe…
Materials Science
X. -G. Wang、W. Weiss、Sh. K. Shaikhutdinov 等 8 位作者1998-07-14arXiv
Using spin-density functional theory we investigated various possible structures of the hematite (0001) surface. Depending on the ambient oxygen partial pressure, two geometries are found to be particularly stable under thermal equilibrium: one being terminated by iron and the other by oxygen. Both exhibit huge surfac…
Materials Science
Alessio Filippetti、Vincenzo Fiorentini1998-07-14arXiv
We present ab initio total energy and stress calculations for the unreconstructed and (2x1)-missing-row reconstructed Ir (110) and Rh (110) surfaces. We use a model based on ab initio results to show that the (Nx1) reconstruction is a faceting transition to a long-wavelength--corrugated (111)-like surface, and find th…
Materials Science
Tim Panczak、Steve Ring、Mark J. Welch1998-07-13SAE technical papers on CD-ROM/SAE technical paper series
<div class="htmlview paragraph">Thermal engineering has long been left out of the concurrent engineering environment dominated by CAD (computer aided design) and FEM (finite element method) software. Current tools attempt to force the thermal design process into an environment primarily created to support struct…
Material Properties and Failure MechanismsMicrostructure and Mechanical Properties of SteelsMetallurgical Processes and Thermodynamics
Shane A. Catledge、Walton Comer、Yogesh K. Vohra1998-07-13Applied Physics Letters
The thickness and surface roughness of diamond films grown on a Ti–6Al–4V alloy in a microwave plasma reactor was measured in situ using optical pyrometry. The growing film results in oscillations of the apparent temperature with time, which can be explained by interference effects caused by reflections from the film/…
Metal and Thin Film MechanicsLaser-induced spectroscopy and plasmaDiamond and Carbon-based Materials Research
Michael Hortsch、D. S. Homer、Jyoti Malhotra 等 7 位作者1998-07-13The Journal of Cell Biology
Expression of the Drosophila cell adhesion molecule neuroglian in S2 cells leads to cell aggregation and the intracellular recruitment of ankyrin to cell contact sites. We localized the region of neuroglian that interacts with ankyrin and investigated the mechanism that limits this interaction to cell contact sites. Y…
Silk-based biomaterials and applicationsCellular Mechanics and InteractionsNeurobiology and Insect Physiology Research
Seiji Kurihara、Kohji Masumoto、Takamasa Nonaka1998-07-13Applied Physics Letters
Polymer-dispersed liquid crystal (PDLC) with macroscopically uniaxial molecular alignment containing azobenzene molecules was produced. The PDLC was transparent because of this alignment. Upon photoirradiation to cause trans-cis photoisomerization of azobenzene molecules, the PDLC became translucent even at 30 °C. The…
Advanced Materials and MechanicsPhotonic Crystals and ApplicationsLiquid Crystal Research Advancements
M. Gioti、S. Logothetidis、Costas A. Charitidis1998-07-13Applied Physics Letters
We have developed amorphous carbon films in sequential layers and studied their intrinsic stress, composition, and stress relief mechanisms. The films were deposited by sputtering either thin, with fixed bias voltage Vb or thick, with alternative (positive-layer A/negative-layer B) Vb. In situ spectroscopic ellipsomet…
Diamond and Carbon-based Materials ResearchMetal and Thin Film MechanicsSemiconductor materials and devices
Alan R. Denton、Hartmut Löwen1998-07-13Physical Review Letters
Freezing of charge-stabilized colloidal suspensions and relative stabilities of crystals and quasicrystals are studied using thermodynamic perturbation theory. Macroion interactions are modeled by effective pair potentials combining electrostatic repulsion with polymer depletion or van der Waals attraction. Comparing…
Advanced Mathematical Theories and ApplicationsQuasicrystal Structures and PropertiesMaterial Dynamics and Properties
V. Vescoli、L. Degiorgi、H. Berger 等 4 位作者1998-07-13Physical Review Letters
We report a study of dc transport properties up to 600 K and of the optical response over a broad spectral range of the two-dimensional (2D) dichalcogenide $2H\ensuremath{-}{\mathrm{TaSe}}_{2}$. Our findings suggest a dynamics of the charge excitation spectrum dominated by two relevant features: a Drude contribution,…
Physics of Superconductivity and MagnetismGraphene research and applications2D Materials and Applications
Gianfranco Pacchioni、Gianluigi Ieranò、Antonio M. Márquez1998-07-13Physical Review Letters
We report ab initio configuration interaction calculations on the optical transitions of the ${E}^{\ensuremath{'}}$ center, a hole trapped at an oxygen vacancy, $(---\mathrm{O}{)}_{3}{\mathrm{Si}}^{\ifmmode\bullet\else\textbullet\fi{}}$ ${}^{+}\mathrm{Si}(\mathrm{O}---{)}_{3}$, in silica. We found two competing excita…
Luminescence Properties of Advanced MaterialsPhotochemistry and Electron Transfer StudiesGlass properties and applications
Hajime Tanaka、Takeaki Araki1998-07-13Physical Review Letters
We demonstrate by numerical simulations that spinodal decomposition of fluid mixtures is strongly dependent upon their ``fluidity,'' which characterizes the relative importance of the two relevant transport mechanisms, hydrodynamic flow and diffusion. Thus, it may not be ``universal,'' at least in two dimensions. For…
Block Copolymer Self-AssemblyPickering emulsions and particle stabilizationMaterial Dynamics and Properties
Sufi Zafar、Robert E. Jones、Bo Jiang 等 7 位作者1998-07-13Applied Physics Letters
The current density is measured as a function of time for thin (⩽1000 Å) barium strontium titanate (BST) capacitors with platinum electrodes. The current density curve shows a peak prior to the onset of resistance degradation. The peak position on the time axis varies with applied voltage and temperature. The data are…
Semiconductor materials and devicesElectronic and Structural Properties of OxidesFerroelectric and Piezoelectric Materials
A.W.R. Leitch、V. Alex、J. Weber1998-07-13Physical Review Letters
We report on a Raman spectroscopy study of float-zone crystalline silicon after exposure to a hydrogen plasma. New lines measured at 3601 and $2622\mathrm{cm}{}^{\ensuremath{-}1}$ are attributed to vibrational excitations of ${\mathrm{H}}_{2}$ and ${\mathrm{D}}_{2}$ molecules, respectively, positioned at the tetrahedr…
Ion-surface interactions and analysisSilicon Nanostructures and PhotoluminescenceSemiconductor materials and devices
A. K. Zvezdin、V. V. Dobrovitski、B. N. Harmon 等 4 位作者1998-07-13arXiv
A new type of mesoscopic quantum effect in large-spin molecules possessing easy-axis anisotropy, such as Mn12, is predicted. The response of such a system to an external field applied perpendicular to the easy axis is considered. It is shown that the susceptibility of this system exhibits a peculiar peak of purely qua…
cond-mat.stat-mechMaterials Science
G. Oshanin、S. Nechaev、A. M. Cazabat 等 4 位作者1998-07-13arXiv
We consider dynamics of an isolated polymer chain with a chemically active end-bead on a 2D solid substrate containing immobile, randomly placed chemically active sites (traps). For a particular situation when the end-bead can be irreversibly trapped by any of these sites, which results in a complete anchoring of the…
Soft Condensed MatterMaterials Science
Antonella Fara、Fabio Bernardini、Vincenzo Fiorentini1998-07-13arXiv
We present ab initio density-functional calculations for acceptors, donors, and native defects in aluminum nitride, showing that acceptors are deeper (Be ~ 0.25 eV, Mg_ 0.45 eV) and less soluble than in GaN; at further variance with GaN, both the extrinsic donors Si_Al and C_Al, and the native donor V_N (the anion vac…
Materials Science
Simon C. Lawson、David Fisher、Damian C Hunt 等 4 位作者1998-07-13Journal of Physics Condensed Matter
Infra-red (IR) absorption results on irradiated and annealed synthetic diamond are presented which confirm an earlier proposal that a component found in the defect-induced one-phonon region of some diamonds arises from positively charged single-substitutional nitrogen . The concentration ratio of to neutral substituti…
Diamond and Carbon-based Materials ResearchAdvanced Surface Polishing TechniquesHigh-pressure geophysics and materials
Adrian Bachtold、M. Henny、C. Terrier 等 8 位作者1998-07-13OpenAlex
Contact resistances of multiwalled nanotubes deposited on gold contact fingers are very large. We show that the contact resistances decrease by orders of magnitudes when the contact areas are selectively exposed to the electron beam in a scanning electron microscope. The focused electron beam enables the selection of…
Force Microscopy Techniques and ApplicationsGraphene research and applicationsCarbon Nanotubes in Composites