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 radiation‐induced grafting to cellulose of styrene, methyl methacrylate, vinyl acetate, 2‐vinylpyridine, and 4‐vinylpyridine in methanol has been studied. All monomers exhibit appreciable grafting at room temperature in either vacuum or air for total doses up to 10 Mrad and at dose rates as high as 1.4 Mr…
Hall-effect measurements have been made on Te-doped GaAs crystals diffused with known amounts of 64Cu sufficient to convert the crystals to p-type. Energy levels are found above the valence band at 0.123±0.005 eV, 0.145±0.005 eV, 0.166±0.005 eV, 0.19±0.005 eV, and 0.43±0.01 eV. An analysis of the Hall data has been ma…
The effects are described of supersaturation, temperature, and relative motion of solution and crystal on the rate of sucrose crystal growth from aqueous solutions containing a wide range of impurities. The results are consistent with the conclusion, drawn from data in pure sucrose solution, that two main steps, neith…
The structure of hemimorphite, Zn 4 Si 2 O 7 (OH) 2 · H 2 O has been redetermined with three-dimensional data obtained both photographically and with a counter-diffractometer. R values of 7.1% and 4.0% were obtained for the two sets of data. There are no significant differences between the Si–O bond lengths (mean 1.62…
Abstract Acrylonitrile grafts readily to granular corn starch in aqueous slurry when initiated by hydrogen peroxide plus activator. Prime evidence for grafting lies in the ease of separating PAN from starch in high yield when the initiator is azobisisobutyronitrile rather than peroxide. Grafting efficiencies are deter…
Abstract Warp‐knitted velour fabrics of Dacron, nylon, polypropylene, and Rayon have been backed with Silastic to form a laminate. Prior to heat curing, the composite can be molded into many shapes and has been successfully used to line the luminal side of blood pumps and vascular grafts. Prosthetic heart valves are b…
The metabolism of collagen was studied by injecting proline-14C into rats and determining the specific activities and total activities of hydroxyproline-14C in the collagen fractions of the skin and in the urine, (a) When proline-14C was injected into thyroxine-treated rats, the total activity of hydroxyproline-l4C in…
Devitrification occurs near the cathode when reconstructed high‐silica glasses and fused quartz undergo electrolysis at 900°C. The crystalline phase is cristobalite and results from a concentration of alkali ions. Subsequent and more superficial crystallization around the alkali‐rich spot is caused by interaction of t…
Abstract The separation nozzle process is based on the partial spatial separation of components of different mass in an expanding supersonic jet stream. The process is of especial interest for the separation of uranium isotopes. Details of a systematic experimental determination of the most favorable operating conditi…
Methods of producing a fibre web for needle-punching on a laboratory machine are described: a parallel-laid card web was suitable for most purposes, though a cross-laid web was less anisotropic. Methods of operation and testing are described; the effects of specimen shape and size on tensile-test results were studied.…
The dielectric constant of zirconia has usually been estimated from data on films. This has led to some values in the region of 12 and some in the region of 25. Since the true value is critical in the interpretation of thin-film behaviour, it has now been determined for the first time on single-crystal material. A val…
The precise temperature dependence of x-ray diffraction effects near the transition temperature of ferroelectric NaNO 2 crystal has been examined. The satellite reflections, 1±σ 5 0, start to appear at T s , 0.2°C below the well-known first-order transition point T t . Marked asymmetry of the satellite reflections was…
A study made of factors influencing sulfide-stress corrosion of a number of low alloy and medium alloy steels showed that their delayed failures when exposed simultaneously to stress and the corrosive action of acidified brine-hydrogen sulfide solutions have most of the features of hydrogen induced, delayed brittle fa…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSensitivities for activation analysis of fifteen light elements with 18-Mev. helium-3 particlesEnzo. Ricci and Richard L. HahnCite this: Anal. Chem. 1967, 39, 7, 794–797Publication Date (Print):June 1, 1967Publication History Published online1 May 2002Published inissue 1 Jun…
Particle size distributions obtained from measurements in a thin section are usually a distorted version of the true distribution. When there is negligible overlap of images the conversion of the observed distribution involves the solution of a Volterra integral equation of the second kind. A closed form of solution i…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHeteropoly blues. III. Preparation and stabilities of reduced 18-molybdodiphosphatesElias Papaconstantinou and Michael T. PopeCite this: Inorg. Chem. 1967, 6, 6, 1152–1155Publication Date (Print):June 1, 1967Publication History Published online1 May 2002Published inissue 1 J…
Abstract Four phenyl‐substituted polyquinoxalines have been prepared by the reaction of combinations of two tetraamines, 3,3′‐diaminobenzidine and 3,3,′4,4′‐tetraaminodiphenyl ether, with two bisbenzils, 4,4′‐dibenzil and 4,4′‐oxydibenzil. The polymers were prepared by melt and solution polymerizations. Melt condensat…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHeteropoly blues. II. Reduction of 2:18-tungstatesMichael T. Pope and Elias PapaconstantinouCite this: Inorg. Chem. 1967, 6, 6, 1147–1152Publication Date (Print):June 1, 1967Publication History Published online1 May 2002Published inissue 1 June 1967https://doi.org/10.1021/ic…
A simple Monte Carlo procedure for simulating the scattering of electron beams with incident energies in the range 5-40 kev has been developed, based on a screened Rutherford cross section and the Bethe continuous energy-loss equation. Despite the approximate nature of the initial scattering data, the calculations agr…
Iron was deposited at room temperature in ultra-high vacuum (5 × 10−8 Torr) onto single-crystal films of copper oriented with (001) parallel to their plane. A shutter was moved between source and substrate so that iron deposits in which there were thickness gradients were obtained. Transmission electron micrographs an…