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 Die Darstellung von Ag 3 BO 3 gelingt durch Umsetzung der binären Komponenten Ag 2 O und B 2 O 3 unter erhöhtem Sauerstoffdruck. Im Bereich von 180–210°C zeigt Ag 3 BO 3 einen reversiblen Farbumschlag von gelb nach rot, der von einem schwachen endothermen Effekt (DTA), jedoch nicht von Strukturänderungen begl…
Abstract The development of heterogeneous structure during the polymerization of a polyurethane system using a polyether diol of M̄ n = 2000 as the soft segment and 4,4′‐diphenylmethane disocyanate extended with 1,4‐butanediol as the hard segment was monitored following the amount of light transmitted by the sample an…
The separation of Aulacoseira from Melosira C. Ag. in 1848 by Thwaites is substantiated with new light and electron microscope observations. Differences between the two genera concern the habitat, position of the nucleus, valve and girdle-band structure and, in Aulacoseira, lack of rimoportulae but presence of a disti…
Abstract A bifunctional polymer is formed when low‐molecular‐weight poly(2,6‐dimethyl‐1,4‐phenylene oxide) (I) reacts with 3,3′,5,5′‐tetramethyl‐4,4′‐diphenoquinone (II). Infrared (IR), nuclear magnetic resonance (NMR), and gel permeation chromotography (GPC) measurements indicate that the quinone is bound covalently…
Constitutive equations of elastoplastic materials with anisotropic hardening and elastic-plastic transition are presented by introducing three similar surfaces, i.e., a loading surface on which a current stress exists, a subyield surface limiting a size of the loading surface and a distinct-yield surface representing…
A method for determining the geometrical surface trap structure of highly insulating polymer films is presented. We compare ’’open-circuit’’ thermally-stimulated current measurements of corona and electron-beam-charged foils. We present the results for three different polymers: polyfluoroethylenepropylene [Teflon (FEP…
Spatial (radial and longitudinal) yield spectra for electron energy degradation in atomic oxygen have been obtained using a Monte Carlo method for 25 eV to 10 keV incident electrons. Four‐dimensional yield spectra have been analytically represented in terms of a model containing three simple microplumes. We find that…
Abstract The decomposition of poly(methyl methacrylate) (PMMA), as a positive resist, in CF 4 /O 2 plasma etching has been studied in the thin film state in order to clarify the factors influencing the dry etching durability of resists. It becomes clear that the major PMMA decomposition in CF 4 /O 2 plasma etching pro…
Flow properties and optical properties in applying and stopping shear on a lyotropic cholesteric liquid crystalline system of concentrated aqueous solutions of hydroxypropyl cellulose have been studied. The wave length dependence of transmitted light intensity through a sample subjected to steady shear have been measu…
Abstract Illite-smectites in cored Dakota Group (Cretaceous) shales and bentonites of the northern Denver Basin, identified using a modification of Reynolds' and Hower's (1970) X-ray diffraction criteria, show decreasing sample-sample expandability ranges, lower modal expandability, and a change from random to ordered…
We have studied the "$5f$, $6d$" electron states of the system $\mathrm{U}{\mathrm{Sb}}_{x}{\mathrm{Te}}_{1\ensuremath{-}x}$ (100) using photoemission spectroscopy with synchrotron radiation. In contrast with the generally accepted picture of uranium chalcogenides and pnictides, we find for UTe that the main $5f$ leve…
Neural tubes whose neural crest had just begun migration were isolated from stage-14 chick embryos, cleaned with 0.1% trypsin, and cultured in transparent hydrated collagen lattices (HCL) in an effect to stimulate in part the three-dimensional environment through which neural crest cells migrate in situ, in the embryo…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe permethylcyclosilanes (Me2Si)5 through (Me2Si)35Lawrence F. Brough and Robert WestCite this: J. Am. Chem. Soc. 1981, 103, 11, 3049–3056Publication Date (Print):June 1, 1981Publication History Published online1 May 2002Published inissue 1 June 1981https://doi.org/10.1021/…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReactivity of the [(.eta.5-C5H5)Ti(Mo5O18)]3- anion: synthesis and structure of MoO2Cl+ and Mn(CO)3+ adductsV. W. Day, M. F. Fredrich, M. R. Thompson, W. G. Klemperer, R. S. Liu, and W. ShumCite this: J. Am. Chem. Soc. 1981, 103, 12, 3597–3599Publication Date (Print):June 1,…
Abstract Elastomeric networks were prepared by end‐linking vinyl‐terminated polydimethylsiloxane (PDMS) chains having number‐average molecular weights of 11.3 × 10 3 g mol −1 . The tetra‐functional end‐linking agent, Si[OSi(CH 3 ) 2 H] 4 , was used in varying amounts smaller than that corresponding to a stoichiometric…
This paper provides the mathematical background on which the previous paper entitled: Determination of the Surface Tilt Angle by ATR, is based. The algebra was considered too lengthy to be incorporated as an appendix to that paper.
Abstract Interstratified kaolinite-smectite minerals form the major part of a pedon transitional between ‘red’ kaolinitic and black smectitic soils in a soil toposequence derived from basalt in Burundi, Central Africa. These interstratified kaolinite-smectites have many X-ray, morphological and chemical features in co…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA monohydroxobridged, strongly antiferromagnetically coupled dicopper(II) center in a binucleating macrocycle. Comparisons with binuclear copper sites in biologyPeter K. Coughlin and Stephen J. LippardCite this: J. Am. Chem. Soc. 1981, 103, 11, 3228–3229Publication Date (Pri…
If a powder pattern consists of well resolved peaks, and if it is adequately described by a crystallographic model, as determined by statistical tests, the estimates of the parameters and their standard deviations will not be significantly different, in a statistical sense, whether the method of refinement uses peak p…
Oxygen self‐diffusion in MgAl 2 O 4 single crystals was investigated by annealing the samples in 18 O enriched gas at 98 kPa (1 atm) and measuring the tracer concentration profiles using a proton activation technique. The diffusion coefficients in the range 1625 to 1925 K for stoichiometric crystals are represented by…