Takashi Kato、Yasuo Kubota、Toshiyuki Uryu 等 4 位作者1997-08-18Angewandte Chemie International Edition in English
Thermal stability (up to 350°C) is one of the characteristics of the supramolecular mesogenic polyamide formed by self-assembly during the complexation between a phyenylbezoic acid and a nylon containing pyridyl units in its backbone. The probable structure of the hydrogen-bonded complex is shown schematically on the…
Liquid Crystal Research AdvancementsAdvanced Polymer Synthesis and CharacterizationSynthesis and properties of polymers
K. Steenbeck、T. Eick、K. Kirsch 等 5 位作者1997-08-18Applied Physics Letters
Epitaxial ferromagnetic manganite films have been sputtered on bicrystal substrates. Their magnetoresistance was measured as a function of magnetic field and temperature. The grain boundary magnetoresistance at low temperature is separated from the intrinsic magnetoresistance near the Curie temperature. The grain boun…
Magnetic and transport properties of perovskites and related materialsMultiferroics and related materialsAdvanced Condensed Matter Physics
L. Brandon Shaw、Barry B. Harbison、Brian J. Cole 等 5 位作者1997-08-18Optics Express
The spectral properties of Pr 3+ doped BaInGaGeSe chalcogenide glasses are reported. Absorption spectra, emission spectra, and lifetimes of the lower lying manifolds have been measured. Radiative transition rates are calculated and compared with measured experimental lifetimes. The strong mid-IR emission and spectral…
Glass properties and applicationsChalcogenide Semiconductor Thin FilmsPhase-change materials and chalcogenides
Douglas J. Pesak、Jeffrey S. Moore1997-08-18Angewandte Chemie International Edition in English
The molecular geometry is mirrored in the macroscopically ordered patterns found in a series of stiff, phenylacetylene dendrimers 1. These compounds form hexagonal columnar liquid crystalline phase with snowflake-like morphologies.
Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsDendrimers and Hyperbranched Polymers
Emanuel Vogel、Martin Bröring、Steven J. Weghorn 等 13 位作者1997-08-18Angewandte Chemie International Edition in English
Promising as a chelating agent and as a photosensitizer hemiporphycene is the third porphyrin isomer after porphycene and corrphycene with a central N4 coordination sphere. The stable octaethyl derivative of hemiporphycene 1 was obtained by the combination of a McMurry reaction a reductive CC cleavage from a bis(tetra…
Molecular Sensors and Ion DetectionPorphyrin and Phthalocyanine ChemistryPhotodynamic Therapy Research Studies
Andreas Berger、Matthew R. Pufall1997-08-18Applied Physics Letters
A complete magneto-optical characterization of any material requires the measurement of both, the magneto-optical and the conventional optical constants. We have developed the method of generalized magneto-optical ellipsometry (GME), which enables us to determine these material constants simultaneously in a single set…
Liquid Crystal Research AdvancementsForce Microscopy Techniques and ApplicationsOptical Polarization and Ellipsometry
Theo M. Nieuwenhuizen1997-08-18Physical Review Letters
In order to find out whether there exists a thermodynamic description of the glass phase, the Ehrenfest relations along the glass transition line are reconsidered. It is explained that the one involving the compressibility is always satisfied, and that the one involving the specific heat is principally incorrect. Ther…
Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesTheoretical and Computational Physics
Fabrizio Cleri、Sidney Yip、D. Wolf 等 4 位作者1997-08-18Physical Review Letters
By isolating the process of dislocation emission from a crack tip under an applied tensile stress, we extract from a molecular dynamics simulation the atomic-level displacement and stress fields on the activated slip plane before and after the nucleation event. The stress-displacement relations so obtained provide a d…
Microstructure and mechanical propertiesHigh Temperature Alloys and CreepNon-Destructive Testing Techniques
Bruno Gompf、R. Günther、G. Nick 等 5 位作者1997-08-18Physical Review Letters
The width of the short light pulses emitted from a single air bubble trapped in a resonant sound field in degassed water has been measured for the first time using time-correlated single photon counting. The pulse width at room temperature increases from about 60 ps at low gas concentrations and low driving pressures…
Ultrasound and Hyperthermia ApplicationsUltrasound and Cavitation PhenomenaPhotoacoustic and Ultrasonic Imaging
R. Martonak、W. Paul、K. Binder1997-08-18arXiv
In this paper we present a Path Integral Monte Carlo (PIMC) simulation of the orthorhombic phase of crystalline polyethylene, using an explicit atom force field with unconstrained bond lengths and angles. This work represents a quantum extension of our recent classical simulation (J. Chem. Phys. 106, 8918 (1997)). It…
Materials Science
T. Y. Koo、S. H. Park、K.-B. Lee 等 4 位作者1997-08-18Applied Physics Letters
Thin films of perovskite manganite La0.7Ca0.3MnO3 were grown epitaxially on SrTiO3(100), MgO(100) and LaAlO3(100) substrates by the pulsed laser deposition method. Microscopic structures of these thin film samples as well as a bulk sample were fully determined by x-ray diffraction measurements. The unit cells of the t…
Magnetic and transport properties of perovskites and related materialsMultiferroics and related materialsAdvanced Condensed Matter Physics
R. Porter、S. Beedoe、V. Singh 等 27 位作者1997-08-18Physical Review Letters
We present measured dielectron production cross sections for $\mathrm{Ca}+\mathrm{Ca}$, $\mathrm{C}+\mathrm{C}$, $\mathrm{He}+\mathrm{Ca}$, and $d+\mathrm{Ca}$ reactions at $1.0\phantom{\rule{0ex}{0ex}}A\mathrm{GeV}$. Statistical uncertainties and systematic effects are smaller than in previous dilepton spectrometer (…
X-ray Spectroscopy and Fluorescence AnalysisNuclear Physics and ApplicationsElectron and X-Ray Spectroscopy Techniques
Naoyuki Ueda、Hideo Hosono、Ryuta Waseda 等 4 位作者1997-08-18OpenAlex
Anisotropy of electrical and optical properties in β-Ga2O3 single crystals has been investigated at room temperature. The conductivity and mobility of the degenerate sample along the direction of b and c axes are 38 Ω−1 cm−1, 46 cm2 V−1 s−1, and 2.2 Ω−1 cm−1, 2.6 cm2 V−1 s−1, respectively. The absorption edges of the…
ZnO doping and propertiesGa2O3 and related materialsElectronic and Structural Properties of Oxides
Jian Ping Lu1997-08-18arXiv
Elastic properties of carbon nanotubes and nanoropes are investigated using an empirical force-constant model. For single and multiwall nanotubes the elastic moduli are shown to be insensitive to structural details such as the helicity, the radius, and the number of walls. The tensile Young's modulus and the torsion s…
Carbon Nanotubes in CompositesGraphene research and applicationsBoron and Carbon Nanomaterials Research
Qijin Chen1997-08-17arXiv
45-degree rotated epitaxial diamond nucleation on both (001) and {111} planes of a silicon substrate was observed using chemical vapor deposition with nucleation enhancement by electron emission. The epitaxial relationship between diamond and Si is D(001)//Si(001) and D<100>//Si<110> in both cases. While the case of d…
Materials Science
Emily J. Wu、James A. Ibers1997-08-15Acta Crystallographica Section C Crystal Structure Communications
Dicaesium trimanganese tetratelluride, Cs2Mn3Te4, has been synthesized at 1173 K and its structure determined from single-crystal X-ray data. Cs2Mn3Te4 is isostructural with Cs2Mn3S4. The structure comprises layers of edge-sharing manganese-centered tetrahedra stacked perpendicular to [001].
Chalcogenide Semiconductor Thin FilmsCrystal Structures and PropertiesSolid-state spectroscopy and crystallography
Matthias Weil、Robert Glaum1997-08-15Acta Crystallographica Section C Crystal Structure Communications
Mercury(II) diphosphate, Hg2P2O7, belongs to the M2X2O7 family of compounds with dichromate-type crystal structures and is isotypic with Cd2P2O7. It consists of alternating layers built from P2O7 groups and highly distorted HgO6 polyhedra with bond distances in the ranges 2.120 (6) ≤ d(Hg1O6) ≤ 2.793 (7) Å and 2.208 (…
Crystal Structures and PropertiesSolid-state spectroscopy and crystallographyX-ray Diffraction in Crystallography
Harukazu Yoshino、Keizo Murata、T. Sasaki 等 8 位作者1997-08-15Journal of the Physical Society of Japan
The magnetoresistance of a quasi-one-dimensional (Q1D) organic superconductor, (DMET) 2 I 3 , where DMET is dimethyl(ethylenedithio)diselenadithiafulvalene, was measured up to 30 T at 1.5 K. An electrical current was applied perpendicular to the conducting a b plane and a magnetic field is rotated in the a b plane. An…
Physics of Superconductivity and MagnetismMagnetism in coordination complexesOrganic and Molecular Conductors Research
M. D. Welter、K. L. Menningen1997-08-15Journal of Applied Physics
The column densities of several molecular radicals are measured in an oxyacetylene torch flame during the growth of diamond films. The column densities of CH, C2, CN, and OH radicals are determined by highly sensitive absorption spectroscopy. The radical densities are measured as a function of position in the flame fo…
Catalytic Processes in Materials ScienceDiamond and Carbon-based Materials ResearchCatalysis and Oxidation Reactions
M. A. Berding、A. Sher、Mark van Schilfgaarde1997-08-15Physical review. B, Condensed matter
Properties of ordered group-IV compounds containing carbon, silicon, and germanium are calculated within the local density approximation. Twenty-seven fully relaxed compounds represented by seven different compound structures are compared and, with the exception of SiC, all compounds are found to be metastable. Two tr…
Graphene research and applicationsBoron and Carbon Nanomaterials ResearchSemiconductor materials and interfaces