Materials Literature
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The examples discussed here represent only a small part of the published work relating to infrared spectra of adsorbed molecules. The publications in this field indicate that infrared spectroscopy is being used for surface chemistry research in about 50 laboratories throughout the world. This effort is mainly devoted…
Abstract A review is made of the yield strength attainable by dispersing particles in a metal matrix in order to hinder dislocation motion. The advantages and drawbacks of the various methods used to introduce the particles are considered. The greatest strengths are found in materials containing a large volume fractio…
Abstract The strengths of solids are examined, and the various factors that determine them discussed. The ideal strength comes directly from the atomic forces but the practical strength depends on the toughness of the material and the effects of stress concentrations. The types of microstructures most suitable for rea…
The frequency and temperature response of the polarization of BaTi${\mathrm{O}}_{3}$ from 1 to 1000 ${\mathrm{cm}}^{\ensuremath{-}1}$ and between 24 and 200\ifmmode^\circ\else\textdegree\fi{}C has been determined by transmission and reflectivity measurements on polarized single crystals. A single absorption band locat…
Over-all optical properties of cubic ZnS: Cl single crystals were studied in order to clarify the nature of the self-activated luminescence center. The characteristic polarizations found both in fluorescence and in thermoluminescence provide the first information about the optical symmetry inherent in the luminescence…
The thermal conductivity along (${K}_{\mathrm{II}}$) and across (${K}_{\ensuremath{\perp}}$) the layer planes of 5 specimens of pyrolytic graphite (PG) in their as-deposited condition has been investigated at temperatures ranging from 1.7 to 300\ifmmode^\circ\else\textdegree\fi{}K. In both directions the conductivity…
The coupling schemes and matrix elements resulting from the first-order spin—orbit perturbation of the lowest n,π* triplet state in halogenated carbonyl compounds are examined. Because of the one-electron nature of Hs·o·, only seven of the 24 states resulting from one-electron transitions in X2CO, are found to perturb…
Mössbauer spectra were measured at 4°, 78°, and 300°K for the two end members and two intermediate samples of the system SrFeO2.5–3.0. Of primary interest is the spectrum of strontium ferrate (IV) which at 300°K consists of a single unsplit line having a full width at half-intensity of 0.39 mm/sec and an isomer shift…
Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation S. E. Hatch, W. F. Parsons, R. J. Weagley; HOT‐PRESSED POLYCRYSTALLINE CaF2:Dy2+ LASER. Appl. Phy…
Abstract Die Herstellung von 99.7‐proz. H 2 O 2 wird beschrieben, ferner eine Kühltruhe für Arbeiten bei Temperaturen bis zu —40′. Durch Einwirkung von Hydroperoxyd wurden kristallisierte Perhydrate von Valin, Citrullin, Nicotinsäureamid und Melamin (1 : 1), von Norvalin, Asparagin, Sarkosin, Betain (2 : 3), von Kreat…
Abstract Measurements of the intrinsic viscosity of a polycarbonate degraded thermally in vacuum show that the polymer undergoes random chain scission according to the equation The viscosity results obtained in methylene chloride yield a value of α, the exponent of the Kuhn‐Houwink equation in agreement with the publi…
Galvanomagnetic and thermoelectric measurements have been performed on doped and undoped ${\mathrm{Bi}}_{85}$${\mathrm{Sb}}_{15\ensuremath{-}}$ alloy single crystals. The thermal gap, obtained from the temperature variation of resistivity on high-purity $n$- and $p$-type samples, is 0.024\ifmmode\pm\else\textpm\fi{}0.…
Abstract The Q and e values for maleimide amount to 0.41 and 1.33 respectively. The chemical reactivity and the IR‐spectrum of polymaleimide are discussed.
Abstract The NMR spectra of a series of compounds were taken in order to identify the nitrogen‐containing linkages which had been considered to be present in polyurethane elastomers. It has been found that the urea, the urethane, the allophanate and the biuret can be discriminated each other by their different chemica…
Phonon-ion interactions have recently been shown to satisfactorily explain the temperature dependence of widths and positions of the $R$ lines of some $3d$ ions in crystals. These interactions give rise to phonon relaxation processes and are investigated here as the mechanisms responsible for the widths and positions…
Irradiation studies of Al2O3-, BeO, and pyrolytic-carbon-coated fuel particles have been carried out in the Battelle Research Reactor. Alumina-coated UO2 particles were found to be capable of a high degree of fission-gas retention during irradiations to at least 10 per cent bumup at temperatures up to 1100 C, The use…
Powders of cadmium sulphide were precipitated with hydrogen sulphide from aqueous solutions of cadmium chloride, bromide, nitrate, and sulphate (and from various mixtures of them) under widely varied concentrations, pH values, and temperatures, and inspected by X-ray diffraction. Hexagonal α-CdS tends to be precipitat…
In field-grown sugar-beet concentration of insoluble oxalate was low in roots and high (about 12 per cent of ethanol insoluble material) in leaves, and for a particular leaf the concentration increased continuously during its life. Of the insoluble oxalate, 15–30 per cent was present as the magnesium salt and the rema…
The velocity of 180° domain walls in BaTiO3 crystals with saltwater electrodes has been measured from 3° to 75°C at applied fields from 0.2 to 200 kV/cm by repeated partial switching and etching. Heating the crystal was found to lower the field required to attain any given wall velocity by a factor which is substantia…
A dynamic torsion testing machine has been built for the purpose of applying a known constant shear stress to a 12.7-mm-diam cylindrical test specimen for very short periods of time. The shear stress at the surface of the specimen rises from zero to any desired value in the range 0 to 3000 psi, within a period of 4 to…