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。
Author: Schuh, Harald et al.; Genre: Book; Finally published : 1987; Keywords: Zugl.: Bonn, Univ., Diss., 1986; Title: Die Radiointerferometrie auf langen Basen zur Bestimmung von Punktverschiebungen und Erdrotationsparametern
Cracking behavior has been investigated through successive observations on the surfaces of five steels, an alpha brass, an age-hardened Al-alloy and a pure titanium, with particular emphasis on the relation between the crack initiation process and the notch sensitivity in fatigue.Two types of crack initiation process…
The characterization of CO–Rh species which are formed on Rh-Y zeolite during exposure to CO has been carried out using the techniques of temperature-programmed description (t.p.d.) and infared spectroscopy (i.r.). The formation of three kinds of CO–Rh species was observed. The first is characterized by a t.p.d. peak…
ABSTRACT The velocities of freely falling water drops released from various heights in still air were measured using two different techniques at an elevation of 1570 m (5150 ft) above sea level. An electrostatic technique was used to measure the time for an electrically charged water drop to pass through two metal rin…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTExpansion of the molybdenum coordination sphere in dinuclear tetrasulfur-bridged complexes with the Cp2Mo2S4 coreL. L. Wright, R. C. Haltiwanger, J. Noordik, and M. Rakowski DuBoisCite this: J. Am. Chem. Soc. 1987, 109, 1, 282–283Publication Date (Print):January 1, 1987Publi…
The principles that control the reactions occurring during the formation of metallic diffusion coatings for the protection of iron and steel are reviewed. Thermodynamic principles are used to examine the reaction mechanisms of coating formation, and are related to the composition and structure of the coatings formed.…
Abstract The influence of water and oxygen concentration on stress corrosion cracking of steels in liquid ammonia. Vapor phase cracking in water‐inhibited ammonia storage spheres is also discussed.
Fluoropolymers have become indispensable materials not only in the chemical industries as the pipe laying, the packing, the gasket etc. of the chemical plants, but also in the electrical industries as the electric line, the cable and so on, as a result of the application of their excellent heat resistance, chemical re…
An investigation is reported in which the thermal resistance of jute and jute-blend fabrics was measured by the double-plate method of BS4745. The relation between thermal resistance and thickness is shown to be linear. The relation between fabric conductivity and fabric packing factor is shown to follow Lee's equatio…
NASA goals for reusable space-based, high-performance orbit transfer vehicle propulsion systems have resulted in a need for oxygen/hydrogen engines which include lightweight, highly reliable, liquid oxygen pumps. The selection of ignition- and burn-resistant materials is a major factor in the design of a compact 75,00…
Abstract
U.v. irradiation of metronidazole (1-hydroxyethyl-2-methyl-5-nitroimidazole) in oxygen-free aqueous solution leads to rearrangement via a labile intermediate to N-(2-hydroxyethyl)-5-methyl-1,2,4-oxadiazole-3-carboxamide. The structure has been verified by crystallographic assignment of a 4-nitrobenzoate derivative.
Pearls have a premium on quality. The quality \ndifferences ate so subtle and discrete that even professionals \nin the pearl trade can make wrong judgements. \nThe value of pearls, on the one hand, is decided on bulk \nby weight and, on the other, by the quality of individual \npearls. Being a bio…
A phase transition between states of a nematic liquid crystal in a spherical drop was detected experimentally and described theoretically. This transition took place between states which differed solely in respect of the symmetry of a topological point defect (hedgehog) at the center of the drop. The transition occurr…
The physical contrast ratios (CRs) of an electrooptic switching element using a pyrimidine type ferroelectric liquid crystal (LC) was investigated. The electrooptic response of the element to the AC square wave voltages was shown to be strongly dependent both on the amplitudes and frequencies of the applied voltages.…
Potentiodynamic polarization techniques were used to determine characteristic pitting potentials for Alloy 800 in chloride and chloride-sulfate media. The effect of chloride concentration in the range of 0.001 to 1 M was investigated. Decreasing chloride concentrations resulted in noble shifts of the critical nucleati…
Abstract X‐ray diffraction, positron annihilation, electron microscopy and bulk density measurements are reported as a function of the degree of acetylation for a linters cotton. Heterogeneous reaction proceeds with a retention of ordered structure in the fibers. Substitution does increase the extent of disorder but i…
m e reactions of the w t a l s a l t s of a-isocyanoacetate e s t e r s with isothiocyanates and isccyanates =re examined.me e f f e c t s of mrliQing the reaction paramstem on t h e altcm of the reaction (Schem?I1 of methyl a-isocyanoacetate ( G I with phew1 isothiocyanate (21 have been studied, thus providing elhawe…
Abstract Copper surfaces were ground or polished to various surface roughnesses and analysed by WDS and EDS. Both K and L photons were analysed at the accelerating voltages 5, 15 and 45 kV. The influence of topography on the K‐peak intensity was negligible, while the L‐peak intensity was rather sensitive to the surfac…
The Frank elastic constant for twist deformation k 22, has been determined as a function of temperature for 5CB and compared with values cited in literature. The results, together with the values of the elastic constants for splay, k 11, and bend, k 33, which have been measured recently by Bradshaw et al. and the valu…