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 The chemistry of p ‐xylelene and of its analogues has been reviewed. Its modes of formation and polymerization to poly‐ p ‐xylelene have been described, and the initiation and hypothetical termination steps have been discussed. The reactions taking place in the gas phase and in the deposited film are contrast…
The force-elongation properties of web fibers produced by the major ampullate gland systems of four species of orb-web-spinning spiders have been determined and compared with the corresponding properties of fibers obtained from the same gland systems by forcible silking. Although all such fibers are highly variable in…
Bulk magnetization measurements were made between 5 and 300 K in fields up to 14 kOe on a series of iron-chromium alloys containing from 2- to 70-at.% Cr. The temperature dependence of the magnetization was analyzed to yield spin-wave stiffness coefficients that are systematically different from values obtained direct…
Abstract The core and valence levels of a series of poly(alkyl acrylates) have been studied by ESCA. From an analysis of the individual component peaks for the C 1 s and O 1 s core levels and from comparison of relative area ratios it is shown that ESCA may be applied to the study of surface compositions. The evidence…
A rapidly converging method for refining approximate atomic models is presented. It combines the conditional structure-factor least-squares procedure described by Waser [Acta Cryst. (1963). 16, 1091-1094] with the conjugate gradient method for solving linear systems [Hestenes & Stiefel, J. Res. Natl. Bur. Stand. (1952…
The nonlinear relationship between current and voltage in the zinc oxide varistor arises from electrical barriers at the grain boundaries in the polycrystalline ceramic. At very low fields, thermionic emission accounts for the majority of the current, with Schottky emission becoming more important as the field increas…
Polycrystalline galena ore, previously deformed in experiments at room temperature, has been annealed at temperatures between 200 degrees and 700 degrees C over periods of up to 30 days. The influence of heating on the galena has been studied by measurement of indentation hardness, by observation of the grain textures…
The application of the technique of the central compound rotatable designs of Box and Hunter to the optimization of an open-end-spinning process is studied, and the advantages of using a minicomputer for such an analysis are discussed. The influence of the rotor diameter, rotor speed, and yarn twist on the characteris…
The skeletal mechanics of Astenas forbesii are examined in order to erect a theoretical framework for the evaluation of starfish skeletal systems. Guided by engineering theory, the skeleton is dissected into its functional parts and an approximation made of the stresses sustained by each. All relevant mathematical ope…
Hardened C 3 S paste cured for 1 year at 20°C was examined to confirm the composition and the morphology of hydrated tricalcium silicate. A new technique was used in which the samples for scanning electron microscopy (SEM) and electron probe microanalysis (EPMA) were etched in 1% HNO 3 ‐alcohol or in glycerol‐alcohol…
This paper describes investigations on the influence of surface roughness on the onset or breakdown voltage in air and SF6. Applying the streamer theorie of electrical discharges the role of ionization characteristic, gas pressure, shape and size of electrode surface protrusions is discussed. The maximum allowable fie…
The effect of the molybdate ion (MoO4=) concentration on the corrosion inhibition of 1010 steel was investigated in aerated chloride/sulfate-containing solutions. The chloride content was 304 ppm Cl-, and the sulfate was 352 ppm SO4=. Weight loss measurements and electrochemical methods were employed for the investiga…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTripositive mercury. Low temperature electrochemical oxidation of 1,4,8,11-tetraazacyclotetradecanemercury(II) tetrafluoroborateRichard L. Deming, A. L. Allred, Alan R. Dahl, Albert W. Herlinger, and Mark O. KestnerCite this: J. Am. Chem. Soc. 1976, 98, 14, 4132–4137Publicat…
The mechanism which gives rise to the anomalous temperature dependence of nonsoft phonons near the lambda transition point in ammonium halides is discussed. The orientation of an ammonium ion in its unit cell is treated as a pseudo-Ising spin, and the Hamiltonian of a pseudospin–phonon coupled system is derived from s…
Tensile experiments in polystyrene (PS) and poly(methyl methacrylate) (PMMA) conducted at constant strain rate over a wide range of pressure and temperature have shown that a brittle-to-ductile transition is induced in these amorphous polymers by the superposition of hydrostatic pressure as well as by the raise of the…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRaman spectra of strained disulfides. Effect of rotation about sulfur-sulfur bonds on sulfur-sulfur stretching frequenciesH. E. Van Wart and H. A. ScheragaCite this: J. Phys. Chem. 1976, 80, 16, 1823–1832Publication Date (Print):July 1, 1976Publication History Published onli…
Abstract not Available.
A constant volume/variable pressure gas permeability apparatus is described that provides accurate determination of permeabilities ranging from less than 10−1 to 106 centibarrers. Metal construction, variable temperature control, adjustable downstream pressure and constant volume, and a differential pressure transduce…
The sonoluminescence from 17 different gases dissolved in water was measured. The results show an inverse relation with the thermal conductivity of the gas. The thermal conduction losses of the gas in the cavitation bubble during its rapid collapse are considered, and an expression found for the final temperature of t…
Copper samples containing dissolved hydrogen up to a few hundred atomic p.p.m. have been prepared by quenching from equilibrium at higher temperatures. Measurements of the annealing of the residual resistivity up to 150°C show that the hydrogen precipitates around room temperature and the precipitation is controlled b…