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。
Summary From the Buranga pegmatite, Rwanda, three occurrences of eosphorite-childrenite series minerals are described in assemblages of Li-Fe-Mn-bearing phosphates and in relationship with quartz-feldspar masses in close association with these assemblages. Electron-microprobe analyses of these terms (Mn,Fe) AlPO 4 (OH…
Double bolt loaded double cantilever beam specimens were used. Increasing chloride ion concentration increased the stress corrosion cracking (SCC) plateau growth rate up to about 0.6M, presumably by increasing the activation of the aluminum surface; at high concentrations the cracking was slower, perhaps because of lo…
Abstract Hydration/dehydration behaviour and the effect of various thermal treatments on montmorillonites saturated with lanthanide ions have been investigated by X-ray diffraction, thermal analysis (DTA, TG, DTG), IR spectroscopy and sorption-desorption of water vapour techniques. Heating at 150°C under 10 −5 torr di…
Observations of the retroreflective or opposition effect in the backscatter of visible radiation from common dielectric surfaces at small phase or observation angles have been made with a beam-splitting technique at zero phase angle with phase-angle resolution just under 0.2°, the smallest known resolution reported to…
SUMMARY Halite (NaCl), the most common halide mineral, is omnipresent in saline soils and frequent in alkaline soils. The present study, with a scanning electron microscope, is undertaken to evaluate the morphologies of this mineral in soils and a recent sediment. Salorthids, from Iran and Syria, and a recent crust fr…
The purposes of this study were (1) to determine any underlying considerations governing the perceptions of professional people as to the appropriateness of specific types of garment styles for female business dress and (2) to determine if a difference exists in the perceptions of appropriateness of garment styles by…
ABSTRACT Some antarctic diatoms form resting spores, differing morphologically and probably physiologically from vegetative cells. Differences in the type of resting stages became apparent while examining three species of endemic Antarctic diatoms (Bacillariophyceae, Centrales): Eucampia balaustium Castracane, Odontel…
Abstract The process of the polymerization of silicic acid can be divided into three steps: (1) a reaction between monosilicic acids, (2) a reaction between monosilicic and polysilicic acids, and (3) a reaction between polysilicic acids. The rates of the reactions between monomer-monomer, monomer-polymer and polymer-p…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStoichiometric inclusion compounds of cyclotriveratrylene and cyclotricatechylene with small neutral molecules. X-ray crystal structure of cyclotricatechylene di-2-propanolateJohn A. Hyatt, Eileen N. Duesler, David Y. Curtin, and Iain C. PaulCite this: J. Org. Chem. 1980, 45…
Both experimental and theoretical evidences are presented for polar and nonpolar contributions to liquid-crystal orientations on surface-treated substrates. Polar and nonpolar components of substrate surface energies are determined from contact angle measurements using polar liquids. Liquid-crystal orientations are ch…
The dielectric behaviour of monovalent ‘metallic’ impurities is considered as a function of the impurity concentration N as N approaches the critical concentration N c for the onset of metallic behaviour. The different types of screening, namely (1) metallic (Thomas–Fermi, Lindhard), (2) classical semiconductor (Debye…
Polycrystalline samples of non-centrosymmetrical enantiomorphic materials may be considered as two-phase materials consisting of a right-handed and a left-handed phase, each of which has its own texture. Centrosymmetrical crystals may be considered as right- or left-handed at the same time. If the right- and left-hand…
Water treeing is a well known fracture phenomenon in polyethylene (PE) and crosslinked polyethylene (XLPE) high voltage cable insulation. We studied two phenomena: (1) The insulation material is mechanically fatigued by electrostriction as is shown by measuring the relevant electrostriction constant, which moreover is…
No abstract available.
A literature survey on the mechanisms of water-treeing electrical cables is presented. The survey provides an introduction, some background, and examples of current research on water-treeing mechanisms. The mechanisms of water-treeing have been broken into three categories: chemical, electrical, and mechanical. Along…
In mammals, a trifunctional protein (ME pyr1-32) synthesizes L-5,6-dihydroorotate in three sequential reactions catalyzed by carbamyl phosphate synthetase (EC 2.7.2.9), aspartate transcarbamylase (EC 2.1.3.2), and dihydroorotase (EC 3.5.2.3). 14C-labeled HCO3- has been used as a precursor for the synthesis of L-5,6-di…
Ca10(PO4)6CO3 is an `apatite' with pseudo-hexagonal symmetry with monoclinic space group Pb and lattice constants a = 9.557 (3) A, b ≃ 2a, c = 6.872 (2) A and γ = 120.36±0.04°.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolyoxoanion-supported metal carbonyls: syntheses of the [(OC)3M(Nb2W4O19)]3- anions (M = rhenium and manganese)C. J. Besecker and W. G. KlempererCite this: J. Am. Chem. Soc. 1980, 102, 25, 7598–7600Publication Date (Print):December 1, 1980Publication History Published onlin…
Various methods of thermogravimetric analysis were compared in case of polystyrene degradation. The reaction order, the activation energy and the preexponential factor were evaluated from common TG curves experimentally obtained. In most cases a 5-mg sample of polystyrene with 110,000 molecular weight was decomposed a…
High mobility group (HMG) protein 14, which, like HMG-17, has been implicated in the structure of 'active chromatin' is shown by 270-MHz NMR and by circular dichroism to be in a disordered conformation in free solution. At low ionic strength protein HMG-14 binds to DNA by weak attachment of the N-terminal half of the…