Materials Literature
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The characteristics of the residual band at 3650 cm–1 in the infra-red spectrum of deuterated aerosils have been determined. The band corresponds to hydroxyl groups and not to molecular water. It is assigned to interacting hydroxyls sited on neighbouring silicon atoms within the solid lattice of the silica particles.…
Monohydroperoxides were isolated from chlorophyll-photosensitised oxidation of methyl oleate, methyl linoleate, methyl linolenate, and ethyl arachidonate. The positions of the hydroperoxide substituent were determined by two methods of analysis of the saturated hydroxy-esters formed by catalytic hydrogenation. Gas–liq…
Cobalt oxalate dihydrate dehydrated at 150° is porous, and the subsequent isothermal decomposition in a vacuum to cobalt differs considerably from the isothermal decomposition of the anhydrous oxalate prepared at a higher temperature. The characteristic feature of the decomposition of the porous anhydrous cobalt oxala…
Abstract The anisotropic resistivity of dislocations produced by deformation is measured in high purity Au, Ag, and Cu single crystals at liquid helium temperature. Resistivities along the direction perpendicular to the slip plane are found to be greater than those parallel to the slip plane. The ratio Δ ϱ⟂ /Δ ϱ∥ (whe…
Prepolished strips of Ti-8Al-1Mo-1V, stressed to the yield point at 650 F, cracked when exposed to either chloride, iodide, or bromide salts. Cracking was most severe in specimens exposed to pure sodium chloride (NaCl). Chemical analyses of corrosion products formed by NaCl exposures showed that aluminum was preferent…
apparently requires four stages of decomposition to reach . Based on thermogravimetric studies the intermediate products appear to be , , and . Although the first three stages seem irreversible, they too come to a steady state in decomposition, but no recombination takes place. and values have been calculated for the…
The electronic spectra and magnetic susceptibilities of the complexes [UCl6]2–, [UCl4Br2]2–, [UBr6]2–, [UCl4(Ph3PO)2], [UCl4(Et3PO)2], and [UBr4(Ph3PO)2] have been measured. Relative values for the nephelauxetic effects, and the ligand fields, of the ligands have been derived. The possibility of spin-pairing in uraniu…
Abstract A theory is developed which accounts for the fine structure of electron diffraction spots due to the presence of imperfections of different types in thin foils. The method consists essentially of considering the diffraction pattern to result from the image (i.e. from the amplitudes of transmitted and scattere…
The phase diagram of the system Ga‐S has been determined. Two maxima are found in the T‐X diagram, one at the composition of , the other at the composition of . The compound has a maximum melting point of 962° ± 4°C at a sulfur pressure of has a maximum melting point of about 1090°C at a sulfur pressure of 1.3 mm Hg.…
Systemal'ic studies were carried out on the Jormation oj rolling textures in 3% Si-Fe single crystals wilh a number oj Ineselecled orientations.
The C form of La2O3 has been prepared and its transformation to the A form is found to take place at ∼590°C. The C→A transformation of Nd2O3 takes place at 550°C. The temperatures as well as the energies of activation of the phase transformations of the rare earth sesquioxides vary with the size of the cation. Y2O3 un…
Abstract The Raman spectrum of a NaNO 2 single crystal in the ferroelectric phase is obtained and the polarization of the lines is investigated. The forms of normal vibrations are considered on the basis of symmetry coordinates and the intensity of lines. Formulae for translational vibrations are derived and numerical…
Fe1,15Ga0,85O3 est piézoélectrique et magnétoélectrique et cristallise dans le groupe orthorhombique non centrosymétrique Pc21n. Les paramètres de la maille sont a = 8,75 Å ; b = 9,40 Å ; c = 5,07 Å ; Z = 8. Le composé est aussi dense que α — Fe2O3 (type corindon α — Al2O 3), comme le montre la comparaison avec la mai…
1-Bromo-1,19-dideoxy-19-methyl(or ethyl)biladiene-ac dihydrobromides are prepared by condensation of the hydrobromide of a 5-bromo-5′-bromomethyldipyrromethene with that of a 5-unsubstituted 5′-methyl(or ethyl)-dipyrromethene in presence of stannic chloride. The 1,19-dideoxybiladiene-ac salts are cyclised to the corre…
The heats of fluorination of germanium and of hexagonal and tetragonal germanium dioxide have been determined calorimetrically by reacting them with fluorine gas. The heat of transition of vitreous into hexagonal germanium dioxide has been determined by solution calorimetry in hydrofluoric acid. The following data hav…
Abstract The thermogravimetric method is shown to offer a simple but valid and meaningful method for assessing the degree of humification of organic soils. Heights of the 280C maxima in the differential thermogravimetric (DTG) curves of 22 organic soil samples, ranging from peats, mucky peats, peaty mucks to mucks, we…
In a number of aqueous environments the increase in the corrosion rate ( i c ) of magnesium with an increase in impressed anodic current ( i ) is expressed by d i c di = τ a where τ a is the transport number of the anions of the electrolyte. This adds confirmation to the viewpoint that film damage by anions rather tha…
Abstract Zircons from different localities show considerable variation in physical properties, and it is generally accepted that these variations are the result of α‐radiation damage due to the presence of radioactive impurities, in particular, uranium and thorium. Transmission electron microscopy has been used to stu…
Abstract The core structure and Peierls barrier for an edge dislocation lying in the {110} plane with Burgers vector along 〈111〉 in body‐centered cubic iron were investigated numerically with the aid of a high speed computer using an anharmonic potential. The core radius is about 5 Å and the corresponding core energy…
Abstract Viscosities of samples of poly(vinyl chloride) in cyclohexanone were measured over a wide range of concentrations, up to polymer weight fractions of the order of 0.4. Polymers with molecular weight from 10,000 to 230,000 and with different molecular weight distributions were studied. The effect of concentrati…