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Reformulation of the fourier modal method for surface-relief gratings made with anisotropic materials

Lifeng Li1998-07-01Journal of Modern Optics

By the use of the correct Fourier factorization rules presented in an earlier paper by Li the Fourier modal method (FMM) for anisotropic surface-relief gratings is reformulated. The newly formulated FMM converges much faster than the old formulation when the permittivity contrast in the grating groove region is large.…

Photonic and Optical DevicesPhotonic Crystals and ApplicationsOptical Coatings and Gratings

Hall effect inLa1−xSrxMnO3

A. Asamitsu、Y. Tokura1998-07-01Physical review. B, Condensed matter

The Hall effect and its systematic variation with doping level $(x)$ and temperature have been investigated for crystals of ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{MnO}}_{3}$ $(0.18<~x<~0.50)$ with perovskite structure. The ordinary Hall coefficient ${(R}_{H})$ at 4.2 K indicates that the carr…

Magnetic and transport properties of perovskites and related materialsMultiferroics and related materialsAdvanced Condensed Matter Physics

Online monitors keep transformers in service

Thomas Leibfried1998-07-01IEEE Computer Applications in Power

The trend toward a deregulated global electricity market is raising utility cost consciousness. An important aspect of cost savings is equipment investment for the power transmission system, and power transformers are among the most expensive elements of a high voltage power system. Cost savings can be realized throug…

High voltage insulation and dielectric phenomenaWater Systems and OptimizationPower Transformer Diagnostics and Insulation

Characterization of Starburst Dendrimers and Vesicle Solutions and Their Interactions by CW- and Pulsed-EPR, TEM, and Dynamic Light Scattering

M. Francesca Ottaviani、Paolo Matteini、Marina Brustolon 等 6 位作者1998-07-01The Journal of Physical Chemistry B

Starburst dendrimers (SBDs) of different generations (size) and level of protonations of their surface amino groups and solutions of dimyristoylphosphatidylcholine (DMPC) vesicles were analyzed, both separately and in mixtures of the two components, by negative-staining transmission electron microscopy (TEM), dynamic…

Luminescence and Fluorescent MaterialsDendrimers and Hyperbranched PolymersElectron Spin Resonance Studies

Determining the cubic susceptibility (3) of films or glasses by the Maker fringe method: a representative study of spin-coated films of copper phthalocyanine derivation

X. H. Wang、D. P. West、Neil B. McKeown 等 4 位作者1998-07-01Journal of the Optical Society of America B

An experimental analysis technique is described for accurate extraction of the coherence length and the complex third-order nonlinear susceptibility χ(3) in films or bulk optical glasses from the Maker fringes obtained by third-harmonic generation measurements. This method permits calculation of the third-order suscep…

Porphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer StudiesSpectroscopy and Quantum Chemical Studies

Reorientations in supercooled glycerol studied by two-dimensional time-domain deuteron nuclear magnetic resonance spectroscopy

R. Böhmer、G. Hinze1998-07-01The Journal of Chemical Physics

The method of stimulated echoes was used to investigate the reorientational mechanism in the selectively deuterated glass-former glycerol, C3D5(OH)3 about 15 K above its calorimetric glass temperature. The reorientation process is fully isotropic. This enables an accurate determination of the decay constant, T1Q, of t…

Spectroscopy and Quantum Chemical StudiesAdvanced NMR Techniques and ApplicationsSolid-state spectroscopy and crystallography

Effects of quenched disorder on La-modified lead zirconate titanate: Long- and short-range ordered structurally incommensurate phases, and glassy polar clusters

D. Viehland、Xinyi Dai、J. F. Li 等 4 位作者1998-07-01Journal of Applied Physics

Structure–property relationship studies have been performed in the La-modified lead zirconate titanate (PLZT) solution as a function of quenched La impurity content and Zr/Ti ratio by transmission electron microscopy, lattice imaging, and dielectric spectroscopy. Investigations were performed for 65/35⩽Zr/Ti⩽90/10. Th…

Ferroelectric and Piezoelectric MaterialsGlass properties and applicationsSolid-state spectroscopy and crystallography

Genetic Algorithms for Structural Cluster Optimization

Matthew Wolf、Uzi Landman1998-07-01The Journal of Physical Chemistry A

Certain aspects of the methodology of genetic algorithms for global structural optimization of clusters were studied. Through systematic investigations of Lennard-Jones clusters with up to 100 atoms, several modifications were made to the genetic algorithm introduced by Deaven and Ho [ Phys. Rev. Lett. 1995, 75, 288].…

Advanced biosensing and bioanalysis techniquesSupramolecular Self-Assembly in MaterialsNanocluster Synthesis and Applications

Refinement of Triclinic Hen Egg-White Lysozyme at Atomic Resolution

Martin Walsh、T. Schneider、Larry C. Sieker 等 6 位作者1998-07-01Acta Crystallographica Section D Biological Crystallography

X-ray diffraction data have been collected at both low (120 K) and room temperature from triclinic crystals of hen egg-white lysozyme to 0.925 and 0.950 A resolution, respectively, using synchrotron radiation. Data from one crystal were sufficient for the low-temperature study, whereas three crystals were required at…

Enzyme Structure and FunctionX-ray Spectroscopy and Fluorescence AnalysisX-ray Diffraction in Crystallography

Ring opening polymerization ofD,L-lactide in the presence of zinc metal and zinc lactate

G. Schwach、Jean Coudane、Robert Engel 等 4 位作者1998-07-01Polymer International

The polymerization of D,L-lactide in the presence of zinc metal was investigated for low values of the monomer/catalyst ratio in order to allow end-group characterization of the growing chains by high resolution 360MHz 1H NMR. The results showed that the polymerization was moisture sensitive and that only a fraction o…

Advanced Polymer Synthesis and Characterizationbiodegradable polymer synthesis and propertiesCarbon dioxide utilization in catalysis

Computation of the near-field pattern with the coupled-wave method for transverse magnetic polarization

Philippe Lalanne、Marie Paule Jurek1998-07-01Journal of Modern Optics

In this paper, an accurate method for computing the elecromagnetic field distribution in lamellar gratings is proposed. The method that relies on the rigorous coupled-wave analysis provides accurate numerical results and avoids possible sources of artefacts due to permittivity discontinuities. Its performance is analy…

Photonic Crystals and ApplicationsOptical Coatings and GratingsNear-Field Optical Microscopy

Functional aspects of the X-ray structure of mitochondrial creatine kinase: a molecular physiology approach.

Uwe Schlattner、Michael Forstner、Michael Eder 等 6 位作者1998-07-01PubMed

Mitochondrial creatine kinase (Mi-CK) is a central enzyme in energy metabolism of tissues with high and fluctuating energy requirements. In this review, recent progress in the functional and structural characterization of Mi-CK is summarized with special emphasis on the solved X-ray structure of chicken Mib-CK octamer…

Enzyme Structure and FunctionATP Synthase and ATPases ResearchBiochemical and Molecular Research

Extrusion of PE/PS blends with supercritical carbon dioxide

Min‐Hee Lee、Costas Tzoganakis、Chul B. Park1998-07-01Polymer Engineering and Science

Abstract The effects of dissolved supercritical carbon dioxide on the viscosity and morphological properties were investigated for polyethylene/polystyrene blends in a twin‐screw extruder. The viscosities of the blend/CO 2 solutions were measured using a wedge die mounted on the extruder. A considerable reduction of v…

Polymer crystallization and propertiesbiodegradable polymer synthesis and propertiesPolymer Foaming and Composites

Novel Doping Mechanism for Very‐High‐Permittivity Barium Titanate Ceramics

Finlay D. Morrison、Derek C. Sinclair、J.M.S. Skakle 等 4 位作者1998-07-01Journal of the American Ceramic Society

Barium titanate (BaTiO 3 ) can be doped with La 3+ ions via partial substitution for Ba 2+ ions; charge balance is maintained by the creation of Ti 4+ vacancies. Samples processed in an atmosphere of 1 bar O 2 and a temperature of 1350°C are insulating and free from electronic defects associated with either O 2 loss o…

Ferroelectric and Piezoelectric MaterialsMicrowave Dielectric Ceramics SynthesisDielectric properties of ceramics

A simple scalar model for magnetic hysteresis

J. Tellinen1998-07-01IEEE Transactions on Magnetics

In the computation of magnetic fields for rotating electric machines, transformers, and reactors, the hysteresis nonlinearity sometimes has to be taken into account. Nowadays, many scalar hysteresis models are known for one-directional fields. The main problem with using these models is that the models are complicated…

Microstructure and Mechanical Properties of SteelsMagnetic Properties and ApplicationsNon-Destructive Testing Techniques

Water Electrolysis Using Diamond Thin‐Film Electrodes

Nobuyuki Katsuki、Eietsu Takahashi、M. Toyoda 等 8 位作者1998-07-01Journal of The Electrochemical Society

Thin, boron‐doped diamond films formed on a silicon substrate were evaluated during water electrolysis in acidic solution in order to determine their potential for industrial use. Though the electrode exhibited overvoltages in excess of 2 V in the industrial current range, ozone gas was produced at a current efficienc…

Fuel Cells and Related MaterialsDiamond and Carbon-based Materials ResearchAnalytical Chemistry and Sensors

Fabrication of Magnetic Spider Silk and Other Silk-Fiber Composites Using Inorganic Nanoparticles

Eric Mayes、Fritz Vollrath、Stephen Mann1998-07-01Advanced Materials

The functionalization of spider silk fibers promises to produce high-strength fibers with very interesting properties, for example, magnetism. A method is described to prepare hybrid spider silk materials by binding inorganic nanoparticles to the surface or near-surface region of a silk fiber immersed in a colloidal s…

Silk-based biomaterials and applications

Single-shot spatially resolved characterization of laser-induced shock waves in water

J. Noack、Alfred Vogel1998-07-01Applied Optics

We have developed an optical method for single-shot spatially resolved shock-wave peak-pressure measurements. A schlieren technique and streak photography were used to follow the propagation of the shock wave. The shock position r as a function of time was extracted from the streak images by digital image-processing t…

Energetic Materials and CombustionUltrasound and Cavitation PhenomenaLaser-induced spectroscopy and plasma

Effects of residual monomer on the degradation ofDL-lactide polymer

Suong‐Hyu Hyon、K. Jamshidi、Y. Ikada1998-07-01Polymer International

The effects of remaining monomer on hydrolysis of poly(DL-lactide) were examined by adding different amounts of monomer to purified polymer samples. The existence of monomer in the polymerization products was found to enhance hydrolytic degradation of the polymer. A porous texture was observed on the SEM photographs o…

biodegradable polymer synthesis and propertiesElectrospun Nanofibers in Biomedical Applications

The application of ultra-high-frequency partial discharge measurements to gas-insulated substations

R. Kurrer、K. Feser1998-07-01IEEE Transactions on Power Delivery

This paper deals with the application of the ultra high-frequency method (UHF-method) for the detection of partial discharges (PD) in gas-insulated substations (GIS). First, a review of the GIS-relevant part of the theory of electromagnetic wave propagation in the UHF-range (300 MHz-3 GHz) is given. New information co…

High voltage insulation and dielectric phenomenaLightning and Electromagnetic PhenomenaPower Transformer Diagnostics and Insulation