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 206098 / 210599 页 · 当前展示 4,121,941–4,121,960 / 4,211,975 条匹配结果 · 摘要仅作预览

Synthesis and Characterization of the Mixed-Valence Diamagnetic Two-Electron-Reduced Isopolytungstate [W10O32]6-. Evidence for an Asymmetric d-Electron Distribution over the Tungsten Sites

Dean C. Duncan、Craig L. Hill1996-01-01Inorganic Chemistry

The synthesis of the unprotonated two-electron-reduced isopolytungstate [W 10 O 32 ] 6 - ( 2 ) is reported here. Additionally, full experimental details are given for the acquisition of both high signal-to-noise and integrable natural-abundance 17 O NMR spectra of polyoxometalates. Titration of an acetonitrile solutio…

Metal-Organic Frameworks: Synthesis and ApplicationsPolyoxometalates: Synthesis and ApplicationsVanadium and Halogenation Chemistry

Building Large Amorphous Polymer Structures: Atomistic Simulation of Glassy Polystyrene

Michael Kotelyanskii、Norman J. Wagner、Michael E. Paulaitis1996-01-01Macromolecules

A technique is presented for generating atomistic models of amorphous polymer structures starting from chain configurations on lattice. The method guarantees Gaussian chain statistics and enables control of chain tacticity and monomer sequence while avoiding severe overlaps between the atoms in the structure. We show…

Material Dynamics and PropertiesTheoretical and Computational PhysicsBlock Copolymer Self-Assembly

Structure and Degradation Behavior of Polypyrrole Doped with Sulfonate Anions of Different Sizes Subjected to Undoping−Redoping Cycles

K. G. Neoh、Kenneth K. S. Lau、Victor Wong 等 5 位作者1996-01-01Chemistry of Materials

The effects of cyclic base/acid treatment on electrochemically synthesized polypyrrole−toluenesulfonate (PPY−TSA) and polypyrrole−poly(styrenesulfonate) (PPY−PSSA) films are investigated. The structural modification of the films during the undoping−redoping process is monitored using spectroscopic techniques and eleme…

Advanced Sensor and Energy Harvesting MaterialsConducting polymers and applicationsAnalytical Chemistry and Sensors

Pore Structure of Carbon−Mineral Nanocomposites and Derived Carbons Obtained by Template Carbonization

Teresa J. Bandosz、Jacek Jagiełło、Karol Putyera 等 4 位作者1996-01-01Chemistry of Materials

The lithium form of taeniolite, intercalated with hydroxyaluminum and hydroxyaluminum−zirconium cations, served as the molecular template for carbon−mineral nanocomposites and derived carbons. The inorganic matrixes were saturated by furfuryl alcohol followed by its interlayer polymerization and carbonization. Carbons…

Supercapacitor Materials and FabricationZeolite Catalysis and SynthesisLayered Double Hydroxides Synthesis and Applications

2H nuclear magnetic resonance study of supercooled toluene: Slow and fast processes above and below the glass transition

G. Hinze、H. Sillescu1996-01-01The Journal of Chemical Physics

2H-NMR spin-lattice relaxation times T1 of phenyl ring deuterated toluene have been measured as a function of temperature (75–290 K) at Larmor frequencies between 13.8 and 55.8 MHz. The results are interpreted by assuming a Cole–Davidson rotational correlation time distribution for the α process dominating T1 at tempe…

Material Dynamics and PropertiesGlass properties and applicationsNMR spectroscopy and applications

Effect of fibronectin amount and conformation on the strength of endothelial cell adhesion to HEMA/EMA copolymers

Jeffrey S. Burmeister、J. D. Vrany、W.M. Reichert 等 4 位作者1996-01-01Journal of Biomedical Materials Research

The effect of substrate surface hydrophobicity on fibronectin (Fn) adsorption and endothelial cell adhesion strength was studied. Bovine aortic endothelial cells (BAEC) were plated for 2 h with and without preadsorbed Fn on slides coated with homopolymers and copolymers of hydrophilic polyhydroxyethylmethacrylate (pol…

Electrospun Nanofibers in Biomedical ApplicationsPolymer Surface Interaction Studies

Models of the Cytochromes. Redox Properties and Thermodynamic Stabilities of Complexes of “Hindered” Iron(III) and Iron(II) Tetraphenylporphyrinates with Substituted Pyridines and Imidazoles

Marlys J. M. Nesset、N. V. Shokhirev、Paul D. Enemark 等 5 位作者1996-01-01Inorganic Chemistry

The Fe III /Fe II and Fe II /Fe I reduction potentials of a series of model hemes have been measured by cyclic voltammetry in dimethylformamide at 25 °C as a function of the concentration of added axial ligands. The six porphyrinate ligands utilized were tetraphenylporphyrin (TPP), tetramesitylporphyrin (TMP), and a s…

Photosynthetic Processes and MechanismsPorphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer Studies

Dissolution of Zeolite in Acidic and Alkaline Aqueous Solutions As Revealed by AFM Imaging

Sadaaki Yamamoto、Shoko Sugiyama、Osamu Matsuoka 等 7 位作者1996-01-01The Journal of Physical Chemistry

Atomic force microscopy (AFM) makes it possible to directly detect morphological changes on the surface of a zeolite that are due to dissolution when the crystal is immersed in either an alkaline (0.1 N NaOH) or acidic (0.2 N H 2 SO 4 ) aqueous solution at room temperature. The AFM images revealed for the first time t…

Geological and Geochemical AnalysisForce Microscopy Techniques and ApplicationsClay minerals and soil interactions

Closely diffusing O–H, amide N–H and methylene C–H oscillators quench the excited state of europium comlexes in solution

Rachel S. Dickins、David Parker、A. Sousa 等 4 位作者1996-01-01Chemical Communications

In octadentate complexes of europium(III) based on 1,4,7,10-tetraazacyclododecane, deuteriation studies and measurements of excited state lifetimes in solution reveal that amide N–H and methylene C–H oscillators afford an intramolecular vibronic deactivation pathway of the excited Eu 5D0 emissive state which, coupled…

Magnetism in coordination complexesRadioactive element chemistry and processingLanthanide and Transition Metal Complexes

Characterization of Starburst Dendrimers by EPR. 4. Mn(II) as a Probe of Interphase Properties

M. Francesca Ottaviani、Fabio Montalti、Maurizio Romanelli 等 5 位作者1996-01-01The Journal of Physical Chemistry

Mn(II) has been used as a probe to investigate the interacting abilities of the various ligand sites at the surface of starburst dendrimers (SBDs) at different protonation conditions, and as a function of generation ( G ), both for half- and full-generation SBDs ( n .5-SBDs and n -SBDs, respectively). The computer-aid…

Advanced Polymer Synthesis and CharacterizationFuel Cells and Related MaterialsDendrimers and Hyperbranched Polymers

Azo Polymers for Reversible Optical Storage. 9. Copolymers Containing Two Types of Azobenzene Side Groups

Mei-Sing Ho、Almeria Natansohn、P. Rochon1996-01-01Macromolecules

A series of copolymers with two structural units 1-(4-nitrophenyl)-2-(4-{[2-(methacryloyloxy)ethyl]ethylamino}phenyl)diazene (DR1M), which contains donor−acceptor substituents in the azobenzene group, and 4-[2-(methacryloyloxy)ethyl]azobenzene (MEA), which has no donor−acceptor substituents was prepared. The maximum o…

Liquid Crystal Research AdvancementsPhotochemistry and Electron Transfer StudiesPhase-change materials and chalcogenides

Some properties of films cast from polyurethane aqueous dispersions of polyether-based anionomer extended with hydrazine

Fernanda M. B. Coutinho、Marcia C. Delpech1996-01-01Polymer Testing

Polyurethanes as aqueous dispersions were synthesized and some mechanical properties of the casted films were analysed. Anionomers prepolymers were prepared in bulk by the reaction of poly(propylene oxide), 4,4′-dicyclohexylmethane diisocyanate and dimethylolpropionic acid. The acid group's neutralization was carried…

Polymer Nanocomposites and PropertiesPolymer composites and self-healingEpoxy Resin Curing Processes

Dynamical criterion for two-dimensional freezing

Hartmut Löwen1996-01-01Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

The dynamical criterion for freezing of three-dimensional colloidal fluids recently proposed by L\"owen, Palberg, and Simon [Phys. Rev. Lett. 70, 1557 (1993)] states that the ratio of the long-time to short-time self-diffusion coefficients has the universal value 0.1 along the fluid freezing line. Based on Brownian dy…

Material Dynamics and PropertiesSpectroscopy and Quantum Chemical StudiesAdvanced Thermodynamics and Statistical Mechanics

Self Consistent Field Calculations of Interactions between Chains Tethered to Spherical Interfaces

Eric K. Lin、Alice P. Gast1996-01-01Macromolecules

Self consistent mean field (SCF) theory is used to investigate the structure of and interactions between layers of polymer chains tethered to a spherical interface. Traditional methods have combined flat geometry results with the Derjaguin approximation to calculate the interaction potentials between curved surfaces,…

Polymer Surface Interaction StudiesForce Microscopy Techniques and ApplicationsAdhesion, Friction, and Surface Interactions

The porphyrinogen–porphyhrin relationship: the discovery of artificial porphyrins

Carlo Floriani1996-01-01Chemical Communications

The oxidation of meso-tetrahydrotetraalkylporphyrinogen, which is the chemical and biochemical precursor of porphyrins, has been reexamined using meso-octaalkyl-porphyrinogen as a model compound. This investigation has led to the discovery of oxidized forms of porphyrinogen other than porphyrins, which we call artific…

Porphyrin and Phthalocyanine ChemistryMetal-Catalyzed Oxygenation MechanismsPorphyrin Metabolism and Disorders

Plasma surface modification of polyimide for improving adhesion to electroless copper coatings

G. Rozovskis、J. Vinkevičius、Janė Jačiauskienė1996-01-01Journal of Adhesion Science and Technology

The influences of oxygen plasma treatment of polyimide (PI) films on the adhesion of electroless copper coatings as well as on the chemical composition of the film surface and the PI surface morphology were investigated. The plasma operating parameters were 1800 W forward power with O2 flowing at a rate of 300 cm3/min…

Electronic Packaging and Soldering TechnologiesSynthesis and properties of polymersTribology and Wear Analysis

Characterization and modeling of metal-film microbolometer

Jin‐Shown Shie、Yeong-Maw Chen、Mang Ou‐Yang 等 4 位作者1996-01-01Journal of Microelectromechanical Systems

The characteristic thermal parameters of a platinum-film microbolometer are extracted from the data of two measuring methods. A simple and accurate equivalent circuit model, along with its thermal behavior, is proposed for the device. Applying the model to simulate some device circuits results in good agreement with t…

Advanced MEMS and NEMS TechnologiesTransition Metal Oxide NanomaterialsAdvanced Sensor Technologies Research

Polyelectrolytes Grafted to Curved Surfaces

Ekaterina B. Zhulina、Oleg V. Borisov1996-01-01Macromolecules

We present a scaling theory to describe equilibrium conformations of weakly charged polyelectrolyte molecules grafted at one end onto impermeable surfaces of various morphologies (spheres, cylinders) and of arbitrary curvature. We focus on the case of sufficiently densely grafted chains, i.e., on curved polyelectrolyt…

Surfactants and Colloidal SystemsPolymer Surface Interaction StudiesElectrostatics and Colloid Interactions

Modeling of the Salt and pH Effects on the Permeability of Grafted Porous Membranes

Kyösti Kontturi、Salvador Mafé、José A. Manzanares 等 5 位作者1996-01-01Macromolecules

A simple theoretical model describing the effects of pH and salt concentration on the permeability and counterion transport number of variable permeability membranes has been presented and validated experimentally for the case of poly(vinylidene fluoride) membranes graft modified with poly(acrylic acid) chains by radi…

Membrane Separation TechnologiesHydrogels: synthesis, properties, applicationsPolymer Surface Interaction Studies