Materials Literature

文献浏览

按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。

清除
第 222198 / 228193 页 · 当前展示 4,443,941–4,443,960 / 4,563,845 条匹配结果 · 摘要仅作预览

Narrow-band resonant grating waveguide filters constructed with azobenzene polymers

Raymond J. Stockermans、P. Rochon1999-06-10Applied Optics

Resonant grating waveguide structures were used to fabricate narrow-bandwidth optical filters. Azopolymer films were deposited on top of slab waveguides, and surface relief gratings were optically inscribed on them to be used as couplers. This technique is a simple one-step process and produces efficient gratings with…

Photonic and Optical DevicesPhotonic Crystals and ApplicationsOptical Coatings and Gratings

Magnetic Roughness and Domain Correlations in Antiferromagnetically Coupled Multilayers

Sean Langridge、Joerg Schmalian、C. H. Marrows 等 5 位作者1999-06-10arXiv

The in-plane correlation lengths and magnetic disorder of magnetic domains in a transition metal multilayer have been studied using neutron scattering techniques. A new theoretical framework is presented connecting the observed scattering to the in-plane correlation length and the dispersion of the local magnetization…

cond-mat.dis-nnMaterials Science

Quantum inelastic conductance through molecular wires

H. Ness、A. J. Fisher1999-06-10arXiv

We calculate non-perturbatively the inelastic effects on the conductance through a conjugated molecular wire-metal heterojunction, including realistic electron-phonon coupling. We show that at sub-band-gap energies the current is dominated by quantum coherent transport of virtual polarons through the molecule. In this…

Materials Science

How to calculate the degree of spin polarization in ferromagnets?

I. I. Mazin1999-06-10arXiv

Different ways to define and to calculate the degree of spin polarization in a ferromagnet are discussed, particularly with respect to spin-polarized tunneling and Andreev reflection at the boundary between a superconductor and ferromagnet. As an example, the degrees of spin polarization for different experiments in F…

Materials Science

Spontaneous flux in a d-wave superconductor with time-reversal-symmetry-broken pairing state at {110} boundaries

Jian-Xin Zhu、C. S. Ting1999-06-10arXiv

The induction of an s-wave component in a d-wave superconductor is considered. Near the {110}-oriented edges of such a sample, the induced s-wave order parameter together with d-wave component forms a complex combination d+e^{iϕ} s, which breaks the time reversal symmetry (BTRS) of the pairing state. As a result, the…

Materials ScienceSuperconductivity

Thermally Assisted Tunneling: An Alternative Model for the Thermoluminescence Process in Calcite

J. F. de Lima、M. E. G. Valerio、E. Okuno1999-06-10arXiv

In this work we investigate the effect of gamma and ultraviolet radiations on the thermoluminescence of Brazilian calcite. The irradiated samples presented three TL peaks at 150, 245 and 320^oC (at a linear heating rate of 1.8^oC/s), with a main emission band centered at 615nm due to the ^4G \to ^6S transition of the…

Materials Science

<title>Coupled structural-magnetic strain model for magnetostrictive transducers</title>

Marcelo J. Dapino、Ralph C. Smith、Alison B. Flatau1999-06-09Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

The growing interest in giant magnetostrictive materials for generation of strains in smart structure systems motivates the development of increasingly accurate performance prediction and optimization tools. We propose a model for the strains generated by magnetostrictive materials in response to applied magnetic fiel…

Shape Memory Alloy TransformationsMagnetic Properties and ApplicationsPiezoelectric Actuators and Control

Solid-State NMR Study of Hydrated Intercalation Compounds of Molybdenum Disulfide

Valentin Alexiev、Holger Meyer zu Altenschildesche、R. Prins 等 4 位作者1999-06-09Chemistry of Materials

Solid-state NMR has been used to study the local coordination environments of the protons and alkali metal cations in hydrated alkali metal intercalation compounds of MoS 2, A x (H 2 O) y MoS 2 (A = Li, Na, K, Cs). The dynamic behavior of the water molecules, which are coordinated to the intercalated A + cations, is c…

Advanced NMR Techniques and ApplicationsSolid-state spectroscopy and crystallographyChemical Synthesis and Characterization

<title>Blocked force investigation of a Terfenol-D transducer</title>

Rick A. Kellogg、Alison B. Flatau1999-06-09Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

The output force-strain relationship typical of the performance of Terfenol-D transducers under varied operating conditions is examined to study transducer blocked force characteristics. The design and construction of a transducer for testing under controlled thermal, magnetic and mechanical load conditions are descri…

Magnetic Properties and ApplicationsNon-Destructive Testing TechniquesElectromagnetic Effects on Materials

<title>Structural integrity of composites with embedded piezoelectric ceramic transducers</title>

Christophe Paget、Klas Levin1999-06-09Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

The objective of this paper is to determine the strength reduction due to the embedment of a piezoelectric ceramic transducer in a composite. The composite was made from carbon/epoxy prepreg with a cross-ply lay-up. The transducer was embedded in the mid-plane of the composite material. The specimens were tested in te…

Material Properties and ApplicationsMechanical and Thermal Properties AnalysisEngineering Applied Research

Phase structures and transition behaviors in polymers containing rigid rodlike backbones with flexible side chains. V. Methylene side‐chain effects on structure and molecular motion in a series of polyimides

Kevin W. McCreight、Jason J. Ge、Mingming Guo 等 9 位作者1999-06-09Journal of Polymer Science Part B Polymer Physics

A series of organo-soluble hairy-rod polyimides was recently synthesized from 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) and di[n-alkyl]-4,4′-diamino-6,6′-dibromo-2,2′-biphenyldicarboxylate with side chains of varying lengths (the numbers of methylene units), BACBP(n). Dynamic mechanical (DM) results reveal…

Liquid Crystal Research AdvancementsEpoxy Resin Curing ProcessesSynthesis and properties of polymers

Synthesis of Zn-, Mn-, and Fe-Containing Mono- and Heterometallated Ethanediyl-Bridged Porphyrin Dimers

Victor Borovkov、Juha M. Lintuluoto、Yoshihisa Inoue1999-06-09Helvetica Chimica Acta

New ethanediyl-bridged unsymmetrical mono- and heterometallated dimers of 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin (H2oep) containing transition-metal ions (Mn and Fe) were synthesized by a facile stepwise metallation/demetallation process under mild conditions. The novel metallation strategy initially involved…

Supramolecular Chemistry and ComplexesPorphyrin and Phthalocyanine ChemistryMetal-Catalyzed Oxygenation Mechanisms

Effects of Cu2+ Ions on the Structure and Reactivity of Todorokite- and Cryptomelane-Type Manganese Oxide Octahedral Molecular Sieves

Elaine Nicolas-tolentino、Zheng-Rong Tian、Hua Zhou 等 5 位作者1999-06-09Chemistry of Materials

The concentration effects on Cu uptake into the structures and reactivity of manganese oxide octahedral molecular sieves (OMS) were investigated. Two sets of 3 × 3-tunnel structure OMS designated as OMS-1 were synthesized by hydrothermal treatment at 160 °C for 48 h. The Cu−OMS-1 series of materials (tunnel substitute…

Supercapacitor Materials and FabricationMesoporous Materials and CatalysisLayered Double Hydroxides Synthesis and Applications

Formation and Dissolution of Gold Nanocrystal Superlattices in a Colloidal Solution

Xiao‐Min Lin、G. M. Wang、C. M. Sorensen 等 4 位作者1999-06-09The Journal of Physical Chemistry B

Gold nanocrystal superlattices were synthesized in colloidal form by ligating the nanocrystal surface with dodecanethiol ligand. Formation and dissolution of the superlattices in the colloid were studied by UV−vis spectroscopy and dynamic light scattering. The phase boundary between nanocrystals and their superlattice…

Gold and Silver Nanoparticles Synthesis and ApplicationsQuantum Dots Synthesis And PropertiesNanocluster Synthesis and Applications

High-field noise in degenerate and mesoscopic systems

F. Green、M. P. Das1999-06-09arXiv

We analyse high-field current fluctuations in metallic systems by direct mapping of the Fermi-liquid correlations to the semiclassical nonequilibrium state. We give three applications. First, for bulk conductors, we show that there is a unique nonequilibrium analogue to the fluctuation-dissipation theorem for thermal…

Mesoscale and Nanoscale PhysicsMaterials Science

Theory and numerical calculation of pattern formation in shrinking gels

Jun-ichi Maskawa、Toshiki Takeuchi、Kazuo Maki 等 5 位作者1999-06-08The Journal of Chemical Physics

We discuss pattern formation in three-dimensional gels with cylindrical shapes during their shrinking such as volume phase transition. A Ginzburg–Landau theory is given for the pattern formation in shrinking gels. A characteristic feature in shrinking gels is the dense layer formed around the gel surface in the early…

Liquid Crystal Research AdvancementsAdvanced Materials and MechanicsScientific Research and Discoveries

Osmotic pressure contribution of albumin to colloidal interactions

Mukta Singh-Zocchi、Anita Andreasen、Giovanni Zocchi1999-06-08Proceedings of the National Academy of Sciences

Two surfaces that come in close contact in a solution with macromolecules present experience an attractive force caused by the osmotic pressure. We present a measurement of this effect by using a micrometer-sized sphere bound to a flat plate through a single molecular attachment in an albumin-containing solution. We o…

Lipid Membrane Structure and BehaviorMaterial Dynamics and PropertiesElectrostatics and Colloid Interactions

Slow structural relaxations of glass-forming Maltitol by modulated DSC calorimetry

O. Bustin、Marc Descamps1999-06-08The Journal of Chemical Physics

The possibilities offered by the modulated differential scanning calorimetry technique to investigate the glass transition are analyzed and discussed on Maltitol. The technique provides specific tools to follow the structural relaxation in the frequency domain above Tg and in the time domain below Tg. Evidence is obta…

Material Dynamics and PropertiesGlass properties and applicationsThermal and Kinetic Analysis

Surface relaxation in CdSe nanocrystals

K. T. Leung、Birgitta Whaley1999-06-08The Journal of Chemical Physics

Total energy minimization is applied to semiempirical tight-binding CdSe nanocrystal models with diameter up to 31 Å. The crystallites have wurtzite lattice structure and ligand-terminated surfaces. It is found that the qualitative features of the surface relaxation in nanocrystals and at bulk surfaces are similar. Wh…

Semiconductor Quantum Structures and DevicesQuantum Dots Synthesis And PropertiesChalcogenide Semiconductor Thin Films

Micropolar theory for two–dimensional stresses in elastic honeycomb

X. L. Wang、W. J. Stronge1999-06-08Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences

A micropolar theory has been used to calculate the stress field generated by a fundamental boundary–value problem in planar elasticity; namely, a normal line force acting on the surface of a honeycomb half–space. In this two-dimensional analysis the microstructure of the honeycomb results in couple stresses and micror…

Numerical methods in engineeringComposite Material MechanicsNonlocal and gradient elasticity in micro/nano structures