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。
A new method for calculating the effect of stacking faults on x-ray and neutron-diffraction patterns is developed. Using a computer-generated, statistically faulted crystal model, we show that it is possible to examine the effect of various types of faults in different lattice types from a simple and unified point of…
A new electro-optical material based on nematic liquid crystal dispersed in a polymer matrix has recently been introduced by Fergason. This technology (termed NCAP, for nematic curvilinear aligned phase) is suitable for making very large area (thousands of square centimeter) light valves and displays. The device consi…
The thermoluminescence (TL) of LiF (TLD-100) has been studied over the temperature range 90 to 300K. A total of nine glow peaks are observed in this temperature interval. The most intense peak is the one at 137K. Besides this, three other peaks at 149, 254 and 275K are well resolved and their growth with exposure coul…
The authors establish rigorously the relationship between the growth constant of uniform trees with two branch points and that of self-avoiding walks. For combs, they estimate the corresponding exponent and study the mean-square lengths of the internal and external branches.
The mean square displacement (MSDS) of the ions in the perovskite KZnF 3 have been derived from neutron scattering measurements between 4 and 1073K. The results are compared with the values calculated in the quasi-harmonic approximation. In the high-temperature regime, only a slight increase of F - -ion anharmonicity…
Abstract With the aim to investigate the influence of structural isomerism on the mesomorphic thermal stability in main chain thermotropic polycondensates, a series of poly(azomethines) and low molecular weight models have been prepared. The model compounds exhibit smectic and/or nematic mesophases whose stabilites ar…
The authors have attempted to provide a relatively brief outline of the current situation regarding the formation and properties of charge density wave states in low-dimensional transition metal compounds. They have chosen to illustrate the types of problem involved by specifically focusing on 1T- and 2H-TaS 2 and TaS…
Abstract The B' localized mode, infrared absorption peak (which is due to {100} platelets) and its relations with other features in the infrared absorption spectrum of type la diamonds have been investigated. It is recognized that it is possible, on the basis of their one-phonon infrared absorption spectra, to separat…
We discuss the electromagnetic scattering of a plane wave by an axionic domain wall, under an arbitrary incident angle. We estimate the reflection coefficient which depends on the plane wave frequency and angle and take always a very small value. The two independent circular polarizations propagate with different velo…
The competition between the charge-density-wave and singlet-superconducting phases is investigated for a strong-coupling quasi-one-dimensional system. For a half-filled band each phase appears separately, while for a quarter-filled band a coexistence region is found.
Triphenylstibinedibromide and its derivatives with tribromo-, and pentachlorophenols have been used as flame-retardant additives for polypropylene. Maximum limiting oxygen index of 31.5 against 18.2 for unfilled polypropylene was obtained in a sample containing 10 phr of triphenylstibinedibromide. However, V-0 rating…
Crystals of CaF2 containing different concentrations of Ce3+ and Mn2+ ions were investigated by means of optical absorption and photoluminescence. The results suggest the preferential pairing of the Mn2+ ions with Ce3+ ions in tetragonal sites (i.e. sites in which the Ce3+ ion is locally compensated by an F-interstiti…
Abstract A semiempirical method is proposed, by which the role of kinetical constraints to the growth in closed tube chemical vapour transport can be evidenced. The method is based on the evaluation of the ratio (Φ) between the quantity D which is related to the semiempirically‐determined average diffusivity of the ga…
Abstract The Poole‐Frenkel effect is often observed in the field‐dependent properties of amorphous materials. Experimentally, it is frequently found that the slopes of log σ versus E 1/2 plots differ from that predicted by the Poole‐Frenkel equation and several theorems have been postulated to explain this discrepancy…
Abstract The development of low toxicity rigid epoxy foams as an alternative to polyurethane foams for electronics encapsulation is described. The basic foam components ‐ epoxy resin, hardener, accelerator, blowing agent and surfactant ‐ are blended to form a two part system which is mixed and foamed when required. Ea…
Article Die Bedeutung der Austenitumwandlung für die Eigenspannungsentstehung beim Schweißen was published on September 1, 1986 in the journal HTM Journal of Heat Treatment and Materials (volume 41, issue 5).
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDehydrobromination of 1,2-dibromoethyoxyethane using various amine basesWayne M. Stalick, Ali Khorrami, and Kimi S. HattonCite this: J. Org. Chem. 1986, 51, 19, 3577–3581Publication Date (Print):September 1, 1986Publication History Published online1 May 2002Published inissue…
Abstract The crystal structure of bis-1,2,5-thiadiazolotetracyanoquinodimethane showed stacks of two-dimensionally expanded sheet-like networks, in which the roughly coplanar molesules are connected to one another by way of the rhombohedral linkage involving short S–NC contacts of 3.03 Å.
For the investigation of magnetic properties at frequencies between 5 mHz and 400 Hz we present an electronic device for measurements at well defined time dependence of the magnetic field strength or the flux density. Any function which is monotonous between two peak values can be produced. The measuring device may be…
An experimental investigation on a low-power dc arcjet with helium propellant was conducted. Objectives were to evaluate the thermal efficiency, to assess the performance of various cathode materials, and to investigate the effects of transpirational cooling from the electrodes. The anode was made of porous tungsten s…