Materials Literature
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The decomposition of the methoxymethyl radical, generated in the mercury-photosensitized decomposition of dimethyl ether, has been investigated over the temperature range 200 to 300 °C and the pressure range 3 to 600 mm Hg. The radical decomposes to give a formaldehyde molecule and a methyl radical. The effects of pre…
The relationships between the third-order elastic constants of monocrystalline and polycrystalline (quasi-isotropic, randomly oriented) solids of cubic symmetry are derived according to elastic strain energy balances assuming negligibly small elastic strain energy contribution from mismatching of the grain boundaries.…
The complex dielectric constant of reduced rutile, $\mathrm{Ti}{\mathrm{O}}_{2\ensuremath{-}x}$, has been measured at frequencies between ${10}^{2}$ and ${10}^{5}$ Hz at temperatures between 1.2 and 50\ifmmode^\circ\else\textdegree\fi{}K. Three distinct relaxation processes have been observed: process I at temperature…
The isotope effect has been measured for self-diffusion in single crystals of zinc parallel and perpendicular to the $c$ axis at seven temperatures in the range 289-418\ifmmode^\circ\else\textdegree\fi{}C. A vacancy mechanism is found, with $\ensuremath{\Delta}K=0.93$, independent of temperature within the experimenta…
In lattices in which not all ions possess inversion symmetry, internal-strain effects give rise to piezoelectricity and contribute to the elastic response. It is possible to describe these internal strains as static optical-phonon-mode displacements and to analyze the internal-strain contributions to the elastic and p…
Piezoelectric Bi12GeO20 crystallizes in the cubic system with space group I23 and lattice constant a = 10.1455±0.0008 Å at 298°K. The complete x-ray scattering pattern within a reciprocal lattice hemisphere of radius (sinθ)/λ = 1.02 Å−1 was determined with PEXRAD. A total of 4812 reflections were measured, resulting i…
Linear thermal-expansion data are given for Ge, Si, GaAs, GaSb, InAs, and InSb at temperatures from 1.89\ifmmode^\circ\else\textdegree\fi{}K to approximately 40\ifmmode^\circ\else\textdegree\fi{}K. The data were obtained using a variable transformer as a sensor and are absolute in sample length changes. At the lowest…
The electrical resistivities and the Hall constants of the compound semiconductors GaSe, Mo${\mathrm{S}}_{2}$, Mo${\mathrm{Se}}_{2}$, and W${\mathrm{Se}}_{2}$, which crystallize in layer structures, have been measured at temperatures ranging from 100 to 700\ifmmode^\circ\else\textdegree\fi{}K. The Hall mobilities deri…
Abstract The distribution of aragonite in the skeletal parts of living organisms is reviewed, and its distribution in fossils is described on the basis of several hundred new determinations. Aragonitic fossils are extensively preserved in Tertiary sediments, and are common in Mesozoic rocks, particularly where the enc…
In electric-field-induced Raman-scattering experiments on the cubic perovskite SrTi${\mathrm{O}}_{3}$, a striking electric field shift and splitting of the "soft" optical phonon mode is observed. Experiments were done at temperatures ranging from 8 to 250\ifmmode^\circ\else\textdegree\fi{}K and for electric fields bet…
The Fano factor in germanium at liquid-nitrogen temperature has been found to be $F=0.129\ifmmode\pm\else\textpm\fi{}0.003$ using $\ensuremath{\gamma}$ rays at energies from 0.122 to 4.8 MeV. $F$ appears to be independent of the primary energy in the investigated energy range. Care has been exercised to eliminate the…
The infrared luminescence spectra of four different crystals of cubic ${\mathrm{Zn}}_{1\ensuremath{-}x}{\mathrm{Fe}}_{x}\mathrm{S}$ with ${10}^{\ensuremath{-}4}\ensuremath{\le}X\ensuremath{\le}{10}^{\ensuremath{-}2}$ have been measured at 5 and 77\ifmmode^\circ\else\textdegree\fi{}K. There is no appreciable luminescen…
It is found that five distinct distant-neighbor interactions must be considered in order to characterize adequately the Heisenberg energy in normal cubic spinels having diamagnetic $A$-site ions. The classical theory of the ground spin state is presented in terms of these interactions, which span a five-dimensional pa…
Measurements of the electrical conductivity, the Seebeck effect, and the Hall effect were performed on hot-pressed Cd${\mathrm{Cr}}_{2}$${\mathrm{Se}}_{4}$ between 77 and 300\ifmmode^\circ\else\textdegree\fi{}K. The conductivity of $n$-type Cd${\mathrm{Cr}}_{2}$${\mathrm{Se}}_{4}$ (In-doped) shows a sharp minimum at 1…
The nonrelativistic limit of the Born cross section for electron-electron bremsstrahlung is integrated over a Maxwell-Boltzmann electron distribution. Results for the spectrum are compared with the electron-ion ($Z=1$) bremsstrahlung spectrum found in the literature. The long-wavelength limit is obtained and compared…
Article Neutronenbeugungsuntersuchung der Strukturen von MgAl2O4- und ZnAl2O4-Spinellen, in Abhängigkeit von der Vorgeschichte was published on November 1, 1967 in the journal Zeitschrift für Kristallographie - Crystalline Materials (volume 124, issue 1-6).
Article Härtetiefenmessung an Stahlwalzen mit Ultraschall / Ultrasonic measurement of hardening depth on steel rolls / Mesure de la profondeur de trempe en cylindres d’acier par ultrasons was published on November 1, 1967 in the journal Materials Testing (volume 9, issue 11).
Article Verfeinerung der Kristallstruktur von Tellurit, dem rhombischen TeO2 was published on November 1, 1967 in the journal Zeitschrift für Kristallographie - Crystalline Materials (volume 124, issue 1-6).
Abstract The effect of thermal history on the melting behavior of several linear polymer and copolymers of ethylene has been studied by using a Perkin‐Elmer DSC‐1 differential scanning calorimeter. Samples of film were heated above their melting point and then cooled at various rates in order to establish a known ther…
A method is described for measuring the optical absorption spectra of the crystalline and liquid phases of a transition-metal salt close to the melting point. Supercooling the liquid permits measuring both phases at the same temperature. This technique was applied to Cs3NiCl5 (mp 547°C) and CsNiCl3 (mp 758°C). It was…