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。
The oxidation‐reduction kinetics of the ferrous‐ferric sulfate system have been measured on a stainless steel surface. The data completely support theoretical equations which describe the potential‐current relationships for such a system. The analysis applies to reversible electrodes and to corroding electrodes where…
The titanium--oxygen system has been studied by means of x-ray powder photographs of preparations quenched after annealing at various temperatures. A number of phases not previously described has been observed, viz., Ti/sub 2/O, TiO (low-temperature modification), Ti/sub 4/O/sub 7/, Ti/sub 5/O/su b 9/, Ti/sub 6/O/sub…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Application of Differential Thermal Analysis to the Study of Reaction Kinetics1Hans J. Borchardt and Farrington DanielsCite this: J. Am. Chem. Soc. 1957, 79, 1, 41–46Publication Date (Print):January 1, 1957Publication History Published online1 May 2002Published inissue 1…
At low overvoltage values, deviations from Tafel behavior for a noncorroding electrode are due primarily to the reverse reaction of the oxidation‐reduction system, and at high overvoltages to concentration and/or resistance polarization. It is shown further that the practice of placing straight lines through a few exp…
Electron ejection from metals by ions is shown in this work to be a surface-sensitive phenomenon which is profoundly affected by the adsorption of a monolayer of foreign gas on an atomically clean metal surface. Monolayer adsorption is shown to decrease the total electron yield, ${\ensuremath{\gamma}}_{i}$, primarily…
The effects of strain amplitude on the internal friction and the Young's modulus of polycrystalline specimens of copper alloys (Cu–Zn, Cu–Al, Cu–P) with various concentrations of solute atoms have been investigated. The results are: 1. The critical stress, up to which the internal friction and the Young's modulus are…
Thermal and electrical properties of tungsten oxide were observed in a wide range of temperature. An entirely new anomaly was found at 1230°C, where the rate of sublimation increased abruptly. The amounts of anomalous heat were found to be 330, 450, 280 and 120 cal/mol at the 330°C, 740°C, 910°C and 1230°C transitions…
Abstract The melting temperatures of two of the crystalline modifications of gutta-percha and their mixtures with either methyl oleate or tetradecane as diluent were determined by x-ray diffraction and dilatometric methods. It was found that the melting temperatures of the two forms in the pure polymer were 64 and 74°…
Abstract Relations between degree of crosslinking and gel fraction in a polymer have been derived by several authors. An important parameter in these relations is the crosslinking index γ, the average number of crosslinks to which one original polymer molecule is linked. The relations have been applied to the determin…
The values for a number of physical properties are reported for a very high density form of thorium dioxide. When specimens of a mixture of 99½% ThO 2 and ½% CaO, by weight, were hydrostatically pressed at 30,000 lb. per sq. in. and heat‐treated for 1 hour at 1800°C., they attained 99.0% of theoretical density. All th…
Measurements of magnetic viscosity in equiaxed isotropic and anisotropic Alcomax III specimens have been made; the anisotropy was induced by cooling the material, from the single phase region, in a magnetic field of 4000 Oe. The results are discussed in terms of the concept of the thermal activation of irreversible do…
Abstract Die Hydridbromide der Erdalkalimetalle (CaHBr, SrHBr, BaHBr) lassen sich durch Zusammenschmelzen von Hydrid und wasserfreiem Bromid bzw. von Metall und Bromid in einer Wasserstoffatmosphäre bei 900° darstellen. Dabei fallen die Verbindungen in großen, glänzenden Blättchen an und ähneln in ihrem Aussehen weitg…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCrystallographic Data. 144-147. Rare Earth Oxides. Yttrium Sesquioxide, Y2O3; Dysprosium Sesquioxide, Dy2O3; Erbium Sesquioxide, Er2O3; Ytterbium Sesquioxide, Yb2O3Eugene. StaritzkyCite this: Anal. Chem. 1956, 28, 12, 2023–2024Publication Date (Print):December 1, 1956Publica…
An investigation has been made of the formation of manganese ferrite by solid‐state reaction from mixtures of Mn 3 O 4 and Fe 2 O 3 in a 1 : 3 mole ratio, employing four different firing cycles. The solid‐state reaction was observed by means of X‐ray diffraction, optical microscopy, mass analysis, and differential the…
Abstract The film theory of liquid‐side resistance to gas absorption, embodying the assumption of a thin stagnant liquid film adjacent to the interface in which steady state diffusion occurs, has long been open to question, particularly in packed columns. Higbie's penetration theory, believed to be more reasonable, pi…
Equations are developed for the current as a function of applied voltage during electrolytic solution or deposition at surfaces which are perfect, atomically rough, or smooth except for the steps of screw dislocations. It is shown that the surface structure does not influence the rate of deposition if the overvoltage…
Verbindung des Cyclopentandion-dicarbonsure-dithylesters (V) umgesetzt. Das wahrscheinlich zuerst entstandene Reaktionsprodukt VI wurde nicht isoliert. Dagegen konnte der thylester VII (C18H18Oh, Schmp. 134-135, korr.) erhalten werden. Die Tatsache, da hierbei der Lactonring geschlossen worden ist, beweist, da die ter…
The permittivity and power factor of ceramic barium titanate and barium titanate solid solutions have been measured as a function of time, starting from the time of cooling the material through the Curie point. Both parameters decrease linearly with log t over periods extending to several years. A theory is proposed w…
Effusion measurements have been carried out with uranium dioxide over a temperature range from 1600° to 2800°K and a pressure range from 10—8 to 6 mm. Four different isotopic compositions, three different effusion cells and two different apparatuses were used. The results are concordant and demonstrate that the oxide…
The phenomenological theory of the thermoelectric effects in a cubic or isotropic electronic conductor is developed. It is shown that, as a consequence of the appropriate Onsager relation, the "gauge" adopted here for the thermoelectric coefficients of a single substance is such that the second Kelvin relation takes a…