Materials Literature
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。
Abstract 1,2-Bis(benzo[b]thiophen-3-yl)ethene derivatives, which possess thermally irreversible and fatigue resistant photochromic properties, were synthesized, cis-1,2-Dicyano-1,2-bis(2-methylbenzo[b]thiophen-3-yl)ethene 1a and 2,3-bis(2-methylbenzo[b]thiophen-3-yl)maleic anhydride 2a underwent reversible photocycliz…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAsymmetric hydroxylation, epoxidation, and sulfoxidation catalyzed by vaulted binaphthyl metalloporphyrinsJohn T. Groves and Peter ViskiCite this: J. Org. Chem. 1990, 55, 11, 3628–3634Publication Date (Print):May 1, 1990Publication History Published online1 May 2002Published…
The specular reflectivity of neutrons has been used to characterize quantitatively the microphase separated morphology of symmetric, diblock copolymers of polystyrene (PS), and polymethylmethacrylate (PMMA), as a function of the total molecular weight of the copolymer where either block is perdeuterated. It is shown t…
Effects of various substituents including chromophores on the second harmonic generation (SHG) of Cyanovinylheteroaromatics were examined. The molecular polarizability was calculated by the PPP MO method to correlate SHG responsiveness with chemical structures. 3-[(2-cyano-2-ethoxycarbonyl)ethenyl]indole 8b exhibited…
The vibronic absorption bands with zero-phonon lines at 1·40, 1·883, and 2·51 eV, the broad absorption band with a maximum near 1·4eV and the series of absorption lines near 3·1 eV, the vibronic luminescence bands with zero-phonon lines at 1·40eV and 2·56 eV, all associated with nickel-related optical centres in synth…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructural transformation of non-oxide chalcogenide glasses. The short-range order of lithium sulfide (Li2S)-phosphorus pentasulfide (P2S5) glasses studied by quantitative phosphorus-31, lithium-6, and lithium-7 high-resolution solid-state NMRHellmut Eckert, Zhengming Zhang,…
We review the development of a strain rate and temperature dependent plasticity model for finite deformation. In particular we address both the method of determining the parameters of the model and the engineering meaning of the parameters in terms of uniaxial stress-strain curves. The ability of the model to predict…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOxygen quenching of electronically excited hexanuclear molybdenum and tungsten halide clustersJulie A. Jackson, Claudia. Turro, Mark D. Newsham, and Daniel G. NoceraCite this: J. Phys. Chem. 1990, 94, 11, 4500–4507Publication Date (Print):May 1, 1990Publication History Publi…
Data have been compiled on the cross sections for the collisions of electrons and photons with atomic oxygen (O). The processes considered are total scattering, elastic scattering, momentum transfer, excitations of electronic states (including fine structure levels of the ground state), ionization, and electron attach…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectron microscopy study of delamination in dispersions of the perovskite-related layered phases K[Ca2Nan-3NbnO3n-1]: evidence for single-layer formationM. M. J. Treacy, S. B. Rice, Allan J. Jacobson, and J. T. LewandowskiCite this: Chem. Mater. 1990, 2, 3, 279–286Publicati…
A low resistivity and high transmittance Sn doped In2O3 (ITO) film was formed on a glass substrate by dc magnetron sputtering and lower sputtering voltage gave a lower resistivity film. At a sputtering voltage of −250 V, the resistivity obtained was 5.0×10−4Ω cm for room temperature substrate, 2.0×10−4Ω cm for 160 °C…
Genetic and protein engineering are components of a new polymer chemistry that provide the tools for producing macromolecular polyamide copolymers of diversity and precision far beyond the current capabilities of synthetic polymer chemistry. The genetic machinery allows molecular control of chemical and physical chain…
Sintering experiments at constant heating rates were employed to estimate the activation energy for sintering in alumina and in alumina containing 5 vol% zirconia or 5 vol% titania. Grain growth, which can complicate the analysis of sintering kinetics data, was suppressed by using uniformly and densely packed grain co…
The micromechanics involved in increased crack growth resistance, K R , due to the addition of TiB 2 particulate in a SiC matrix was analyzed both experimentally and theoretically. The fractography evidence, in which, the advancing crack was attracted to adjacent particulates, was attributed to the tensile region surr…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTWater soluble hyperbranched polyphenylene: "a unimolecular micelle?"Young H. Kim and Owen W. WebsterCite this: J. Am. Chem. Soc. 1990, 112, 11, 4592–4593Publication Date (Print):May 1, 1990Publication History Published online1 May 2002Published inissue 1 May 1990https://pubs…
The self‐assembly of intelligent supermolecular materials , for example, liquid crystalline polymers, is the subject of this communication. Employing units based on tartaric acid in the molecular recognition process (see figure) allows the effects of chirality to be investigated as the recognition which occurs at a mo…
An ultrasmall superparamagnetic iron oxide (USPIO) preparation was developed that is small enough to migrate across the capillary wall, a prerequisite in the design of targetable particulate pharmaceuticals. Seventy percent of particles were smaller than 10 nm; 26%, smaller than 5 nm. The blood half-life of USPIO in r…
Abstract It is demonstrated that semiempirical methods give electrostatic potential (ESP) derived atomic point charges that are in reasonable agreement with ab initio ESP charges. Furthermore, we find that MNDO ESP charges are superior to AM1 ESP charges in correlating with ESP charges derived from the 6‐31G* basis se…
The isotopic substitution method in neutron diffraction is applied to two chalcogenide glasses on the (${\mathrm{Ag}}_{2}$S${)}_{\mathit{x}}$(${\mathrm{As}}_{2}$${\mathrm{S}}_{3}$${)}_{1\mathrm{\ensuremath{-}}\mathit{x}}$ (0\ensuremath{\le}x\ensuremath{\le}1) tie line of the Ag-As-S system. It is shown that there is a…
Conducting gels of ultrahigh molecular weight polyethylene and the soluble conjugated polymer poly(3-octylthiophene), P3OT, were prepared by thermoreversible gelation from semidilute solutions in decalin, and subsequent doping with iodine. We report the results of frequency-dependent complex conductivity measurements…