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Predicted power laws for delayed switching of charge-density waves

Steven H. Strogatz、Robert M. Westervelt1989-11-15Physical review. B, Condensed matter

We analyze delayed conduction in three recent models of switching charge-density waves. Each model predicts a power-law dependence of switching delay near threshold: \ensuremath{\tau}\ensuremath{\sim}${\ensuremath{\varepsilon}}^{\mathrm{\ensuremath{-}}\ensuremath{\beta}}$, where \ensuremath{\tau} is the delay and \ens…

Quantum and electron transport phenomenaMolecular Junctions and NanostructuresOrganic and Molecular Conductors Research

Crystallization and diffusion in composite TiO2-SiO2 thin films

H. Sankur、W. J. Gunning1989-11-15Journal of Applied Physics

The crystallization behavior of evaporated TiO2-SiO2 mixed composition films and its dependence on composition, temperature, time and type of mixing (codeposited or alternating layers) were studied. All codeposited films annealed between 600 and 900 °C with 15%–90% molar TiO2 exhibited crystallization in the anatase p…

Advanced ceramic materials synthesisSemiconductor materials and devicesSilicone and Siloxane Chemistry

Size-dependent surface-plasmon resonances of bare silver particles

James R. Heath1989-11-15Physical review. B, Condensed matter

Surface-plasmon resonances of silver microparticle aerosols have been measured as a function of average particle size. Resonance line shapes are modeled as a function of particle size and complex refractive index. The surface-plasmon frequency is found to exhibit a red shift from 3.8 to 3.4 eV as the average particle…

Gold and Silver Nanoparticles Synthesis and ApplicationsAtmospheric aerosols and cloudsnanoparticles nucleation surface interactions

The propagation of a solid-state combustion wave in Ni-Al foils

Umberto Anselmi‐Tamburini、Z.A. Munir1989-11-15Journal of Applied Physics

The use of thin foils to investigate the propagation of a combustion wave has been demonstrated for the nickel-aluminum system. The initiation of a reaction wave in the foils was found to be triggered by the melting of nickel regardless of the composition of the foil ensemble. In contrast, the propagation rate decreas…

Energetic Materials and CombustionIntermetallics and Advanced Alloy PropertiesMetallurgical and Alloy Processes

Correlation between the activation enthalpy and Kohlrausch exponent for ionic conductivity in oxide glasses

K. L. Ngai、Steve W. Martin1989-11-15Physical review. B, Condensed matter

We have established for alkali ions in oxide glasses a strong correlation between the fractional (Kohlrausch) exponent \ensuremath{\beta} in the conductivity relaxation function, exp[-(t/${\ensuremath{\tau}}^{\mathrm{*}}$${)}^{\ensuremath{\beta}}$], and the activation energy ${E}_{a}^{\mathrm{*}}$ of ${\ensuremath{\ta…

Luminescence Properties of Advanced MaterialsGlass properties and applicationsNuclear materials and radiation effects

Capacitance corrections for disc electrodes on sheet dielectrics

H. J. Wintle、D. G. W. Goad1989-11-14Journal of Physics D Applied Physics

The authors present a numerical calculation of the edge capacitance corrections for thin unguarded disc electrodes placed on opposite faces of a dielectric sheet or film. As a function of the ratio (a/h) of electrode radius to sample thickness, the correction grows logarithmically for small values of the sample dielec…

High voltage insulation and dielectric phenomenaPower Transformer Diagnostics and InsulationMicrowave and Dielectric Measurement Techniques

Phenylalanine-to-tyrosine singlet energy transfer in the archaebacterial histone-like protein HTa

Dennis G. Searcy、Thérèse Montenay-Garestier、Claude Hélène1989-11-14Biochemistry

The Archaebacterium Thermoplasma acidophilum has a histone-like protein (HTa) abundantly associated with its deoxyribonucleic acid. Each native tetrameric complex of HTa contains 20 phenylalanine residues, 4 tyrosine residues, and no tryptophan. When the protein was excited by radiation at 252 nm, which is a wavelengt…

Protein Structure and DynamicsPhotosynthetic Processes and MechanismsEnzyme Structure and Function

Investigation of I-V characteristics in polycrystalline BaTiO3

W. Osak、Katarzyna Tkacz1989-11-14Journal of Physics D Applied Physics

Polarisation currents were investigated in polycrystalline BaTiO 3 in order to investigate its I-V characteristics. All but one of the measurements were performed at temperatures below the Curie point, for voltages between 1 V and 1000 V. The experimental curves consist of three parts of different shape: a region in w…

Ferroelectric and Piezoelectric MaterialsMultiferroics and related materialsElectronic and Structural Properties of Oxides

Kinetics parameters in BeO thermoluminescent material

C. Bacci、P. Bernardini、A Damilano 等 5 位作者1989-11-14Journal of Physics D Applied Physics

Kinetics parameters of BeO thermoluminescent material are presented. Thermoluminescence emission from irradiated BeO shows two well separated peaks. Using a linear heating rate of 8.07 K s -1 , the peak temperatures at maximum are 495 and 642 K respectively. Various methods have been used for trap parameter determinat…

Advanced Chemical Physics StudiesLuminescence Properties of Advanced MaterialsCatalysis and Oxidation Reactions

Electrochromic properties of conducting polyanilines

Peter J.S. Foot、Richard Simon1989-11-14Journal of Physics D Applied Physics

A study has been made of the electrochromic behaviour of polyaniline films of potential use in passive display devices, and a preliminary examination of the properties of substituted polyanilines has also been carried out. Films of 'emeraldine-type' conducting polyanilines have been grown electrochemically from aqueou…

Electrochemical sensors and biosensorsConducting polymers and applicationsAnalytical Chemistry and Sensors

Periodic and quasiperiodic wavefunctions in a class of one-dimensional quasicrystals: an analytical treatment

M Severin、M. Dulea、R. Riklund1989-11-13Journal of Physics Condensed Matter

The one-dimensional, discrete Schrodinger equation is studied analytically for a class of quasiperiodic Hamiltonians known as the copper mean. The lattice is described by a recursion formula S L+1 =S L-1 S L-1 S L , L=2,3, . . ., given the two initial sequences S 0 and S 1 . Extended states are shown to exist for ener…

Quasicrystal Structures and PropertiesX-ray Diffraction in Crystallography

Low-temperature deposition of diamond films for optical coatings

T. P. Ong、R. P. H. Chang1989-11-13Applied Physics Letters

A low-temperature (≊400 °C) plasma-enhanced chemical vapor deposition process has been developed to grow diamond films for optical coatings application. Films with fine grains (≤3000 Å) have been obtained by controlling diamond nucleation. The surface roughness of the films is on the order of 50–200 Å. The optical tra…

Diamond and Carbon-based Materials ResearchForce Microscopy Techniques and ApplicationsSurface Roughness and Optical Measurements

Temperature-induced hcp-bcc phase transformation in zirconium: A lattice and molecular-dynamics study based on anN-body potential

F. Willaime、Carlo Massobrio1989-11-13Physical Review Letters

Molecular-dynamics computations based on a simple tight-binding interatomic potential fitted to hcp zirconium confirm the Burgers mechanism for the temperature-dependent hcp-bcc phase transition. In our model the transverse ${\mathrm{T}}_{1}$ [110]-bcc N-point phonon, which is involved in the transition, is unstable i…

Nuclear Materials and PropertiesMachine Learning in Materials ScienceInorganic Chemistry and Materials

Far-infra-red microbolometers made with tellurium and bismuth

Stuart M. Wentworth、Dean P. Neikirk1989-11-09Electronics Letters

The properties of bismuth and tellurium microbolometers are presented. The TE devices are shown to have responsivitics approximately 100 times that of the more conventional Bi microbolometers. The Te device impedance is, however, much larger than Bi microbolometers of comparable size. To our knowledge, the Te device h…

Gas Sensing Nanomaterials and SensorsTransition Metal Oxide NanomaterialsInfrared Target Detection Methodologies

Liquid Transport In Micron And Submicron Channels

Larry J. Kricka、P. Wilding、J. Pfahler 等 6 位作者1989-11-09Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

There has been a growth of interest in fluid transport in very small structures. The basis for this interest derives from the application of micromachining technology to problems in fluidics. Several aspects of this problem are reviewed and discussed including some of our recent research on this topic. The problems di…

Surface Modification and SuperhydrophobicityRheology and Fluid Dynamics StudiesExperimental and Theoretical Physics Studies

Approximants of quasiperiodic structures generated by the inflation mapping

M. Duneau1989-11-07Journal of Physics A Mathematical and General

The problem of deriving explicit coordinates for quasicrystal approximants is solved in all cases where the quasicrystal has an inflation symmetry. In the higher-dimensional space R n , from which the quasiperiodic pattern is obtained by the cut method, the inflation symmetry is represented by a hyperbolic modular mat…

Analytic and geometric function theoryQuasicrystal Structures and PropertiesX-ray Diffraction in Crystallography

Determination and structural application of anisotropic bond polarisabilities in complex crystals

Hans Weber、Michael D. Schulz、Sarah Schmitz 等 5 位作者1989-11-06Journal of Physics Condensed Matter

It is shown that very small atomic displacements of about 10 -9 AA can be detected by polarisation optical methods. The idea for such an optical determination of structural motions is based on an empirical model which considers the anisotropic polarisability and the orientation of the bonds as the origin of the optica…

Nonlinear Optical Materials ResearchSolid-state spectroscopy and crystallographyChemical Thermodynamics and Molecular Structure

Highly mobile oxygen holes in magnesium oxide

Minoru M. Freund、Friedemann Freund、F. Batllo1989-11-06Physical Review Letters

High-purity MgO exhibits an unexpected giant anomaly of the apparent static dielectric constant and positive surface charge of the order of 5\ifmmode\times\else\texttimes\fi{}${10}^{21}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$ in the top 15 nm. We postulate that the MgO matrix contains traces of peroxy defects, ${\…

Semiconductor materials and devicesMicrowave Dielectric Ceramics SynthesisElectronic and Structural Properties of Oxides

Observation of critical phenomena in a protein-water solution

Peter Schurtenberger、Richard Chamberlin、George M. Thurston 等 5 位作者1989-11-06Physical Review Letters

We report measurements of the intensity of the scattered light and the turbidity of aqueous solutions of the bovine lens protein, ${\ensuremath{\gamma}}_{\mathrm{II}}$-crystallin, near the critical point for binary liquiid phase separation, in a region of the phase diagram which is metastable with respect to protein-c…

Proteins in Food SystemsEnzyme Structure and FunctionCrystallization and Solubility Studies

Optical reflectivity measurements using a laser plasma light source

Michael Bortz、Roger H. French1989-11-06Applied Physics Letters

Light produced by a laser plasma light source (LPLS) is used to perform optical reflectivity measurements on single crystals from 5 to 40 eV in a single experiment. The intense continuum generated by the rare-earth plasma allows a significantly higher resolution above 15 eV and extends the measurements to higher energ…

Laser-induced spectroscopy and plasmaElectron and X-Ray Spectroscopy TechniquesSurface Roughness and Optical Measurements