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 265558 / 275833 页 · 当前展示 5,311,141–5,311,160 / 5,516,655 条匹配结果 · 摘要仅作预览

Twinning and growth kinetics of lamellar grains in a diblock copolymer solution

Thomas Q. Chastek、Timothy P. Lodge2005-01-04Journal of Polymer Science Part B Polymer Physics

Abstract The initial stages of growth of the lamellar phase in a block copolymer solution were observed with polarizing optical microscopy (POM). Measurements were made on a poly(styrene‐ b ‐isoprene) diblock copolymer with block molecular weights of 15 and 13 kg/mol, respectively, dissolved in dioctyl phthalate with…

Advanced Polymer Synthesis and CharacterizationPolymer Surface Interaction StudiesBlock Copolymer Self-Assembly

Effects of electric and magnetic fields on phase-separatedLa0.7Sr0.3MnO3−δthin films

I. Pallecchi、L. Pellegrino、E. Bellingeri 等 5 位作者2005-01-04Physical Review B

We perform field-effect experiments on side-gate devices made of underdoped ${\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}\mathrm{Mn}{\mathrm{O}}_{3\ensuremath{-}\ensuremath{\delta}}$ epitaxial thin films. The resistance modulation is small due to the high carrier concentration in this compound; however, it is significantly…

Magnetic and transport properties of perovskites and related materialsAdvanced Condensed Matter PhysicsElectronic and Structural Properties of Oxides

Tear anisotropy in films blown from polyethylenes of different macromolecular architectures

Li-Bong W. Lee、Richard A. Register、David M. Dean2005-01-04Journal of Polymer Science Part B Polymer Physics

Abstract Blown films of different types of polyethylenes, such as branched low‐density polyethylene (LDPE) and linear high‐density polyethylene (HDPE), are well known to tear easily along particular directions: along the film bubble's transverse direction for LDPE and along the machine direction (MD) for HDPE. Dependi…

Polymer crystallization and propertiesRheology and Fluid Dynamics StudiesPolymer Foaming and Composites

Quantum-Chemical Investigation of the Electroabsorption Spectra of Directly Meso−Meso-Linked Porphyrin Arrays: Essential Role of Charge-Transfer Excited States Accidentally Overlapping with Soret Bands

Yoichi Matsuzaki、Atsushi Nogami、Yuji Iwaki 等 8 位作者2005-01-04The Journal of Physical Chemistry A

The electroabsorption (EA) spectra of directly meso-meso-linked porphyrin arrays (Zn, n = 1-3) have been investigated by means of the sum-over-states (SOS) approach at the INDO/S-SCI level theory. The experimental EA spectra of Zn (n > or = 2) exhibit an unusual second-derivative line shape at the exciton split low-en…

Photosynthetic Processes and MechanismsPorphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer Studies

FTIR spectroscopic investigation of thermal effects in semi‐syndiotactic polypropylene

Michael Sevegney、Rangaramanujam M. Kannan、A. R. Siedle 等 4 位作者2005-01-04Journal of Polymer Science Part B Polymer Physics

Abstract The temperature‐dependent behavior of individual components within metallocene‐catalyzed semisyndiotactic polypropylenes (semi‐sPP) with a wide range of stereoregular content (26 to 96% rr ) is studied using Fourier transform infrared (FTIR) spectroscopy and temperature‐modulated differential scanning calorim…

Polymer crystallization and propertiesPolymer Nanocomposites and Propertiesbiodegradable polymer synthesis and properties

Morphology and mechanical properties of binary triblock copolymer blends

Ralf Lach、Roland Weidisch、Konrad Knoll2005-01-04Journal of Polymer Science Part B Polymer Physics

Abstract The influence of the morphology on the mechanical properties of binary styrene–butadiene (SB) triblock copolymer blends of a thermoplastic block copolymer and a thermoplastic elastomer (TPE) with different molecular architectures was studied with bulk samples prepared from toluene. Both block copolymers conta…

Polymer crystallization and propertiesAdvanced Polymer Synthesis and CharacterizationBlock Copolymer Self-Assembly

Preparation of Poly(silylene-p-phenylene)s Containing a Pendant Fluorophor and Their Applications to PL Imaging

Joji Ohshita、Taisuke Uemura、Dong-Ha Kim 等 6 位作者2005-01-04Macromolecules

Poly(silylene- p -phenylene)s bearing an anthrylethynyl, pyrenylethynyl, or terthienyl group as the pendant were obtained in moderate yield, by substitution reactions of poly[ethoxy(methyl)silylene- p -phenylene] with the corresponding organolithium reagents in THF. The polymers exhibited photoluminescent (PL) propert…

Organic Electronics and PhotovoltaicsOrganic Light-Emitting Diodes ResearchConducting polymers and applications

Thermodynamic calculations on the catalytic growth of multiwall carbon nanotubes

Christian Klinke、Jean–Marc Bonard、Klaus Kern2005-01-04Physical Review B

We have developed a thermodynamic model of the catalytic growth of multiwall carbon nanotubes from hydrocarbon precursors at elevated temperature. Using this model we have computed the heat distribution and carbon concentration in the catalyst. Calculations delivered an analytical formula for the growth time and growt…

Carbon Nanotubes in CompositesGraphene research and applicationsFullerene Chemistry and Applications

Growth of Binary Alloyed Semiconductor Crystals by the Vertical Bridgman-Stockbarger Process with a Strong Magnetic Field

Stephen J. LaPointe、Nancy Ma、D. Mueller2005-01-04Journal of Fluids Engineering

This paper presents a model for the unsteady species transport for the growth of alloyed semiconductor crystals during the vertical Bridgman-Stockbarger process with a steady axial magnetic field. During growth of alloyed semiconductors such as germanium-silicon (GeSi) and mercury-cadmium-telluride (HgCdTe), the solut…

Aluminum Alloy Microstructure PropertiesSolidification and crystal growth phenomenananoparticles nucleation surface interactions

Effect of external electric field on the surface energetics ofAg∕Si(111)

Yao He、Xinyuan Wei、C. T. Chan 等 4 位作者2005-01-04Physical Review B

Based on first-principles calculations, we found that the surface adsorption energetics of Ag on a Si(111) surface can be modified by imposing an external electric field. The preferred adsorption site is found to be field dependent. The most energetically favorable adsorption site of Ag on the Si(111) surface, among a…

Graphene research and applicationsSemiconductor materials and devicesSemiconductor materials and interfaces

Rheological and structure investigation of shear‐induced crystallization of isotactic polypropylene

Maria Rossella Nobile、L. Bove、E. Somma 等 5 位作者2005-01-04Polymer Engineering and Science

Abstract In the present work, the influence of well‐defined simple shear flow histories on the isothermal crystallization of an isotactic polypropylene (i‐PP) has been investigated. At first, the research of the flow conditions in terms of temperature, shear rate ( $\dot{\gamma}$ ) and shear strain (γ) has been perfor…

Polymer crystallization and propertiesPolymer Nanocomposites and PropertiesRheology and Fluid Dynamics Studies

Novel biodegradable poly(butylene succinate)/poly(ethylene oxide) blend film with compositional and spherulite‐size gradients

Bayar Hexig、Hexig Alata、Naoki Asakawa 等 4 位作者2005-01-04Journal of Polymer Science Part B Polymer Physics

Abstract Biodegradable poly(butylene succinate) (PBS)/poly(ethylene oxide) (PEO) polymer blend film with compositional gradient in the film thickness direction was prepared using a method of interdiffusion across the interface between the PBS and PEO layers at a temperature above the melting points of both the compone…

Polymer crystallization and propertiesPolymer Nanocomposites and Propertiesbiodegradable polymer synthesis and properties

Characteristics of constrained ferroelectricity in PbZrO3∕BaZrO3 superlattice films

Cheng-Lung Hung、Yu‐Lun Chueh、Tai‐Bor Wu 等 4 位作者2005-01-04Journal of Applied Physics

An Artificially layered perovskite composed of antiferroelectric PbZrO3 and paraelectric BaZrO3 (BZO) was fabricated on LaNiO3∕Pt∕Ti∕SiO2∕Si substrates at 475 °C by radio-frequency magnetron sputtering. It had an (001)-oriented superlattice structure with an average composition of (Pb0.75Ba0.25)ZrO3 (PBZ). X-ray diffr…

Ferroelectric and Piezoelectric MaterialsMultiferroics and related materialsMicrowave Dielectric Ceramics Synthesis

Organosoluble, low‐dielectric‐constant fluorinated polyimides based on 2,6‐bis(4‐amino‐2‐trifluoromethylphenoxy)naphthalene

Chin‐Ping Yang、Sheng‐Huei Hsiao、Cheng‐Lin Chung2005-01-04Polymer International

Abstract A novel fluorinated bis(ether amine) monomer, 2,6‐bis(4‐amino‐2‐trifluoromethylphenoxy) naphthalene, was prepared through the nucleophilic aromatic substitution reaction of 2‐chloro‐5‐nitrobenzotrifluoride and 2,6‐dihydroxynaphthalene in the presence of potassium carbonate, followed by catalytic reduction wit…

Epoxy Resin Curing ProcessesSynthesis and properties of polymersSilicone and Siloxane Chemistry

Electrically commanded surfaces for nematic liquid crystal displays

L. Komitov、Bertil Helgée、Johan M. Felix 等 4 位作者2005-01-04Applied Physics Letters

Electrically commanded surfaces (ECS) is a liquid crystal display concept whereby the switching of the alignment layer, which is driven by an electric field applied across the layer, is further transferred to the bulk liquid crystal material via elastic forces. This work presents the electro-optic response of a sandwi…

Liquid Crystal Research AdvancementsAdvanced Materials and MechanicsPlant Reproductive Biology

Enhanced photoluminescence of Ga2O3:Dy3+ phosphor films by Li+ doping

Miao Pang、Wancheng Shen、Jun Lin2005-01-04Journal of Applied Physics

Ga 2 O 3 : Dy 3 + and Li+-doped Ga2O3:Dy3+ phosphor films were prepared by a Pechini sol-gel process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy, and photoluminescence (PL) spectra as well as lifetimes were used to characterize the resulting thin films (and powder…

Advanced Photocatalysis TechniquesZnO doping and propertiesGa2O3 and related materials

Method of Determining Nanoparticle Core Weight

Fred Reynolds、Terry O'Loughlin、Ralph Weissleder 等 4 位作者2005-01-04Analytical Chemistry

Polymer-coated metal or metal oxide nanoparticles have a variety of uses in industry, biological research, and medicine. Characterization of nanoparticles often includes determination of the dimensions of the electron-dense core by transmission electron microscopy (TEM), with the weight of the core determined from cor…

Nanoparticle-Based Drug DeliveryGold and Silver Nanoparticles Synthesis and ApplicationsIron oxide chemistry and applications

Resurrecting the Ancestral Enzymatic Role of a Modulatory Subunit

Miguel A. Ballícora、Jennifer R. Dubay、Claire H Devillers 等 4 位作者2005-01-04Journal of Biological Chemistry

In the post-genomic era, functional prediction of genes is largely based on sequence similarity searches, but sometimes the homologues bear different roles because of evolutionary adaptations. For instance, the existence of enzyme and non-enzyme homologues poses a difficult case for function prediction and the extent…

Genomics and Phylogenetic StudiesProtein Structure and DynamicsEnzyme Structure and Function

Micellar Aggregates of Amylose-block-polystyrene Rod−Coil Block Copolymers in Water and THF

Katja Loos、Alexander Böker、Heiko Zettl 等 6 位作者2005-01-04Macromolecules

Amylose- block -polystyrenes with various block copolymer compositions were investigated in water and in THF solution. Fluorescence correlation spectroscopy, dynamic light scattering (DLS), and asymmetric flow field-flow fractionation with multiangle light scattering detection indicate the presence of unimers, oligome…

Block Copolymer Self-AssemblyElectrostatics and Colloid InteractionsField-Flow Fractionation Techniques

Structural and electronic properties ofLaMnO3under pressure: Anab initioLDA+Ustudy

Giancarlo Trimarchi、N. Binggeli2005-01-04Physical Review B

The structural and electronic properties of $\mathrm{La}\mathrm{Mn}{\mathrm{O}}_{3}$ under hydrostatic pressure are investigated by means of ab initio $\mathrm{LDA}+\mathrm{U}$ calculations, based on ultrasoft pseudopotentials. Previous theoretical studies have indicated that the local-density approximation (LDA) inco…

Magnetic and transport properties of perovskites and related materialsRare-earth and actinide compoundsAdvanced Condensed Matter Physics