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。
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPrecision neutron diffraction structure determination of protein and nucleic acid components. I. Crystal and molecular structure of the amino acid L-alanineM. S. Lehmann, T. F. Koetzle, and W. C. HamiltonCite this: J. Am. Chem. Soc. 1972, 94, 8, 2657–2660Publication Date (Pr…
A review is presented of the direct numerical approach to the study of the atomic vibrational properties of disordered systems. The basis and details of the numerical methods employed are first described. This is followed by a review of applications of the approach to two-component disordered lattices, glasses, mixed-…
The annual meetings of Commission XIV were held on the occasion of the Annual Assembly of the International Institute of Welding in Lausanne from 16 to 19 July 1970. They were attended by 43 delegates, experts, observers and temporary experts from 20 different countries. Two countries tied for top honours in represent…
Single crystals of magnesium containing varying amounts of In, Al, Pb and Bi in solid solution have been deformed in tension over a range of temperature between 4.2°k and 500°k. The critical resolved shear stress (CRSS) for basal slip has been examined in the light of the existing solution hardening theories. The earl…
Abstract A method to prepare thermally stable resin fiber‐reinforced composites using solutions of appropriate monomers is described. Solutions containing a dimethyl ester of an aryl tetracarboxylic acid, the monomethyl ester of 5‐norbornene‐2,3‐dicarboxylic acid and an aryl diamine were used to impregnate graphite fi…
The temperature-composition phase diagram of ${\mathrm{V}}_{1\ensuremath{-}x}{\mathrm{Cr}}_{x}{\mathrm{O}}_{2}$ with $0\ensuremath{\le}x\ensuremath{\le}0.025$ is found to contain four phases: rutile ($R$), normal monoclinic V${\mathrm{O}}_{2}$ (${M}_{1}$), and two monoclinic phases (${M}_{2}$ and ${M}_{3}$). For ${M}_…
Static and dynamic pore-collapse relations for ductile porous materials are obtained by analysis of the collapse of a hollow sphere of incompressible elastic-plastic material, with appropriate pore radius and over-all porosity. There are three phases of the pore-collapse process: an initial phase, a transitional elast…
Abstract Investigations concerning selective sorption and fixation of K and similar cations by clay minerals and soil clays and the mechanisms of these reactions are reviewed. In particular, recent observations on selective sorption of these ions in dilute solutions by weathered micas and vermiculite in relation to th…
This is the abridged version of a comprehensive volume on the thermal conductivity of the elements. It contains recommended reference values resulting from critical evaluation, analysis, and synthesis of all the available data. It also gives estimated values for those elements for which no thermal conductivity data ar…
A theory is developed to predict the interfacial properties between two immiscible polymers. A self-consistent-field approach is employed to describe the configurational statistics of polymer molecules in the interfacial region. The density profiles and surface tension are calculated, and compare well with experiments…
A 4×4-matrix technique was recently introduced by Teitler and Henvis for finding propagation and reflection by stratified anisotropic media. It is more general than the 2×2-matrix technique developed by Jones and by Abelès and is applicable to problems involving media of low optical symmetry. A little later, we develo…
We have made sound-velocity measurements in the liquid crystal $p$-methoxy-benzylidine, $p\ensuremath{-}n$-butyl-aniline. Near the nematic-isotropic phase transition we observe a dispersion in the sound velocity. Quantitative measurements are presented on the sound-velocity anisotropy in an oriented liquid crystal.
Unlike prior attempts to describe the motion of electronic charge carriers in disordered materials, we suggest that the (holelike) charge carriers may actually be selftrapped, i.e., small polarons. In support of our hypothesis, we discuss our measurements of the electrical conductivity, thermoelectric power, and Hall…
When an electric field is applied perpendicularly to a cholesteric planar texture, periodic perturbations arise. The frequency dependence of the threshold of this instability is reported for nematic-cholesteric mixtures with both positive and negative dielectric anisotropy. In the latter case a "conduction" and a "die…
A molecular field treatment of the B-site spinel was used to determine the ordering temperatures and the asymptotic Curie temperature in terms of the exchange integrals. The theory was developed from a 16-sublattice model and took into account interactions between an atom and its nearest to fourth-nearest neighbors. E…
Resistance changes associated with precipitation in Al–Cu thin films were monitored during power annealing at current densities up to 4×106 A/cm2 and temperatures of ∼178 and 200 °C. The rate of change of resistance decreased as the current increased. It is argued that this decrease is due to the current inhibiting th…
Experimental values of damage rates have been obtained for titanium for electron irradiations in the energy range 0.30-0.50 MeV. A suitable preirradiation annealing treatment has been found, and a value of 19.2\ifmmode\pm\else\textpm\fi{}1.0 eV is determined for the threshold energy of atomic displacement for titanium…
Thin tantalum single-crystal foils with the $〈110〉$ direction normal to the surface have been irradiated with electrons of energies between 1.0 to 3.2 MeV. By varying the orientation of the foil relative to the direction of the beam over a major part of the fundamental triangle, a strong directional effect in the dama…
Inelastic neutron scattering spectra have been obtained at high resolution from a number of aromatic polycrystals, mainly halogenated benzenes, in the range 4 cm−1-1600 cm−1, at room temperature and below. Since the spectra observed reflect only nuclear motion (in contrast to optical spectroscopy), analysis reveals di…
The longitudinal magnetoresistance of a thin metal film has been calculated using Chambers's method. It is assumed that the electron Fermi surface as well as the bulk mean-free path are spherically symmetric. Contrary to previous work based on the assumption of wholly diffuse surface scattering, we consider that scatt…