Д. Б. Литвин、V. Kopský2000-07-01Acta Crystallographica Section A Foundations of Crystallography
A relationship exists between factor groups of space groups and subperiodic groups. This relationship, an isomorphism between factor groups of reducible space groups and subperiodic groups, can be used in the derivation of higher-dimensional space groups, of lattices of space groups, and of irreducible representations…
Quasicrystal Structures and PropertiesDigital Image Processing TechniquesPigment Synthesis and Properties
A. Howie2000-07-01Microscopy and Microanalysis
Abstract In large bandgap semiconductors and insulators, the threshold energies for e–h pair production and ionization damage can lie above the vacuum level. For low energy imaging, a window is then opened whose width is potentially sensitive to local changes in work function, doping level, or acidity. Recent progress…
Advanced Electron Microscopy Techniques and ApplicationsElectron and X-Ray Spectroscopy TechniquesIntegrated Circuits and Semiconductor Failure Analysis
W. Li、I. Andrienko、D. Haneman2000-07-01Journal of Applied Physics
The stability and reproducibility of current–voltage curves of Schottky barrier structures on particular porous silicon surfaces used for obtaining electroluminescence is greatly improved by first coating the surface with a conducting polymer, poly-4-dicyanomethylene-4H-cyclopenta [2,1-b:3,4-b′] dithiophene. With such…
Semiconductor materials and devicesSilicon Nanostructures and PhotoluminescenceNanowire Synthesis and Applications
Wei‐Guo Yin、Ruibao Tao2000-07-01Physical review. B, Condensed matter
We present a self-consistent effective-medium theory for the giant magnetoresistance of magnetic granular samples and doped ${\mathrm{LaMnO}}_{3}$ perovskites on the basis of the resistor network model. Most of the characteristic features of the field and temperature-dependent magnetoresistance can be qualitatively ex…
Magnetic and transport properties of perovskites and related materialsMultiferroics and related materialsAdvanced Condensed Matter Physics
Annette L. Nolan、Robert C. Burns、Geoffrey A. Lawrance 等 4 位作者2000-07-01Acta Crystallographica Section C Crystal Structure Communications
The title compound, Na8[MnW6O24]·18H2O, exhibits a structure with six WO6 octahedral edge-sharing units surrounding a central centrosymmetric MnO6 octahedron, with all metal atoms in a common plane. There are three unique Mn—O distances of 1.903 (7), 1.905 (7) and 1.941 (7) Å [average 1.916 (17) Å], while the average…
Metal-Organic Frameworks: Synthesis and ApplicationsPolyoxometalates: Synthesis and ApplicationsChemical Synthesis and Characterization
Der‐Jang Liaw、Ching-Cheng Huang2000-07-01Macromolecular Chemistry and Physics
Different types of sulfobetaines and their corresponding cationic monomers and polymers derived from N,N-dialkylamino phenyl methacrylamide have been synthesized for this study. Comparing the chemical shifts in 1H and 13C NMR of the methylene groups in the cationic monomers and betaines reveal that the respective meth…
Advanced Polymer Synthesis and CharacterizationDendrimers and Hyperbranched PolymersSynthesis and properties of polymers
A. S. W. Wong、Ranganathan Krishnan、G. Sarkar2000-07-01Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) have been employed in the investigation of the surface chemistry and oxidation-resistant property of the C-, N-, and Cu-containing films, formed by the plasma treatment of pristine copper. The copper oxidation process has been elucidated usin…
ZnO doping and propertiesSemiconductor materials and devicesCopper Interconnects and Reliability
Maria G. Krzhizhanovskaya、Yu. K. Kabalov、Р. С. Бубнова 等 5 位作者2000-07-01Crystallography Reports
The crystal structure of α-RbB3O5 was refined by the Rietveld method with due regard for anisotropic vibrations of rubidium atoms to R p = 2.93, R wp = 3.80, R B = 2.53, R F = 2.84, and s = 1.54. The compound is isostructural to CsB3O5: it is orthorhombic, sp. gr. P212121, a = 8.209(1), b = 10.092(1), c = 5.382(1) Å,…
Crystal Structures and PropertiesNuclear materials and radiation effectsX-ray Diffraction in Crystallography
E. Torijano、R.A. Vargas、J.E. Diosa 等 4 位作者2000-07-01physica status solidi (b)
The high temperature phase behaviour of NH4H2PO4 (ADP) was studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and thermogravimetric (TG) analysis in the temperature range of 300 to 500 K. The DSC results show peaks at 430 and 483 K, that are associated with different phase transformations. The…
Nonlinear Optical Materials ResearchSolid-state spectroscopy and crystallographyChemical Thermodynamics and Molecular Structure
Chang-Seop Koh、Song–Yop Hahn、Soo‐Gil Park2000-07-01IEEE Transactions on Magnetics
A vector hysteresis modeling algorithm is suggested to model the hysteresis phenomena of an isotropic magnetic material. The algorithm combines the Stoner-Wohlfarth and Preisach models. The vector property of each single domain magnetic particle with uniaxial anisotropy, which is supposed to constitute the magnetic ma…
Magnetic properties of thin filmsElectric Motor Design and AnalysisMagnetic Properties and Applications
В. А. Пащенко、A. G. M. Jansen、M. I. Kobets 等 5 位作者2000-07-01Physical review. B, Condensed matter
Electron spin resonance experiments have been performed on single crystals of $\mathrm{KTm}({\mathrm{MoO}}_{4}{)}_{2}.$ In the frequency range from 10 to 190 GHz, the magnetic field dependence of absorption spectra of the ${\mathrm{Tm}}^{3+}$ ions is studied at helium temperatures for different crystal orientations. I…
Luminescence Properties of Advanced MaterialsGlass properties and applicationsSolid-state spectroscopy and crystallography
Hong Zhang、Jun‐ichi Hanna2000-07-01Journal of Applied Physics
The photohole generation process in the smectic phases of a liquid crystalline photoconductor, 2-(4′-octylpheny)-6-dodecyoxylnaphthalene (8-PNP-O12) with different illuminated contact electrodes was investigated through steady-state and transient photocurrent measurements. It was revealed that the photogeneration of h…
Liquid Crystal Research AdvancementsPhotochemistry and Electron Transfer StudiesPhotochromic and Fluorescence Chemistry
Alessandrο Pavese、Gilberto Artioli、A. Hoser2000-07-01Zeitschrift für Kristallographie - Crystalline Materials
Neutron powder diffraction data collection has been carried out at BENSC (Berlin, D), on synthetic Mg 0.94 Al 2.04 O 4 spinel, in the temperature range 300-1700 K, to investigate the intracrystalline cation and vacancy order-disorder (OD) reaction, which begins to be detectable at 944 K. The Rietveld method has been u…
Crystal Structures and PropertiesNuclear materials and radiation effectsX-ray Diffraction in Crystallography
M. Rizzo、A. Savini、J. Turowski2000-07-01IEEE Transactions on Magnetics
The paper proposes a reluctance network method for the three-dimensional analysis of a three-phase transformer. The analysis is aimed at assessing as to whether a laminated flux collector is effective in controlling the power losses of the transformer. The results are thoroughly superimposable to those which can be ob…
Magnetic Properties and ApplicationsPower Transformer Diagnostics and InsulationThermal Analysis in Power Transmission
Masashi Hashimoto、Seiji Ujiie、Akira Mori2000-07-01Chemistry Letters
Abstract New troponoid liquid crystals with an electron-withdrawing cyano group at the C-5 position of tropolone and 2-aminotropone rings were prepared. Tropolone derivatives had nematic phases with lower thermal stabilities and smectic A phases with higher thermal stabilities than the corresponding benzenoids while t…
Liquid Crystal Research Advancements
Michael Vergöhl、N. Malkomes、Bernd Szyszka 等 6 位作者2000-07-01Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
Silver films were deposited using direct current (dc) and midfrequency (MF) magnetron sputter deposition processes on floatglass in order to achieve maximum reflectivity over the entire visual and infrared spectral range. The films were investigated by means of ex situ and in situ spectroscopic ellipsometry, spectral…
ZnO doping and propertiesChalcogenide Semiconductor Thin FilmsCopper-based nanomaterials and applications
Krystian Roleder、Irena Jankowska‐Sumara、G. E. Kugel 等 6 位作者2000-07-01Phase Transitions
For PbZrO3 and PbZr0.99Ti0.01O3 single crystals the first order Raman light scattering spectra in the paraelectric phase have been analysed. In lead zirconate two kinds of crystals, with and without a transient phase, were investigated. It was found that temperature dependence of the defect-induced soft mode frequency…
Acoustic Wave Resonator TechnologiesSolid-state spectroscopy and crystallographyOptical and Acousto-Optic Technologies
Roberto Greco、Michele Iavarone2000-07-01Polymer Engineering and Science
Abstract Differential scanning calorimetry (DSC), scanning electron microscopy (SEM) rheological, mechanical and impact tests were performed on alloys consisting of polycarbonate (PC) and diverse acrylonitrile‐butadiene‐styrene copolymers (ABS), from which different amounts of low molecular (M) weight (W) species had…
Polymer crystallization and propertiesbiodegradable polymer synthesis and propertiesPolymer Foaming and Composites
J. Farkas、Sándor Békássy、Béla Ágai 等 5 位作者2000-07-01Synthetic Communications
Using a series of clay based catalysts (KSF, KSF/0, KP10, K10, K0, KS), resorcinol is acylated in 1,2-dichloroethane by phenylacetyl chloride with a heterogeneous catalytic procedure. The yield of 1-(2,4-dihydroxyphenyl)-2-phenyl-ethanone is in correlation with the specific surface area of the catalyst.
Zeolite Catalysis and SynthesisMesoporous Materials and CatalysisAnalytical Chemistry and Chromatography
Tae Kyoung Kim、Byung Ihn Choi、Sun Won Park 等 7 位作者2000-07-01American Journal of Roentgenology
OBJECTIVE: We determined the enhancement features of experimentally induced malignant tumors on MR imaging with the use of gadolinium mesoporphyrin, a recently developed MR contrast agent that may be necrosis-specific. MATERIALS AND METHODS: VX2 carcinoma was inoculated into 24 rabbit thighs. T1-weighted contrast-enha…
Nanoparticle-Based Drug DeliveryPhotodynamic Therapy Research StudiesLanthanide and Transition Metal Complexes