Pliego general de condiciones para la recepción de aglomerantes hidráulicos en las obras de carácter oficial
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The Hydrogen Positions in Uranium Hydride by Neutron Diffraction1
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Hydrogen Positions in Uranium Hydride by Neutron Diffraction1R. E. RundleCite this: J. Am. Chem. Soc. 1951, 73, 9, 4172–4174Publication Date (Print):September 1, 1951Publication History Published online1 May 2002Published inissue 1 September 1951https://pubs.acs.org/doi/…
Electrical Properties ofαFe2O3andαFe2O3Containing Titanium
Electrical conductivity, Hall effect, and Seebeck effect have been measured on two sets of polycrystalline samples of $\ensuremath{\alpha}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$ and $\ensuremath{\alpha}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$ containing from 0.05 to 1.0 atomic percent titanium ($n$-type impurity). One set of sam…
The Deformation and Ageing of Mild Steel: II Characteristics of the L ders Deformation
In this paper, some of the factors which influence the appearance of Lüders bands in mild steel are studied. It is shown that the Lüders band is adequately described by a uniform shear front, spreading over the specimen. In coarse-grained specimens, experiments indicate that this front becomes diffuse; diffuse bands a…
Infra-red spectroscopic studies of globular protein structure
Abstract The infra-red absorption bands associated with the peptide groups in globular proteins, folded synthetic polypeptides and α-fibrous proteins are very similar. The spectra of denatured globular proteins, extended chain synthetic polypeptides and β-fibrous proteins are also very similar. Denatured fibrous insul…
The thermal conductivities of some dielectric solids at low temperatures (Experimental)
Abstract An apparatus is described in which the thermal conductivity of solids can be determined at any temperature between 2 and 90°K. Several glasses and dielectric crystals have been measured. It had previously been found that at high temperatures the conductivity of glasses is proportional to the specific heat, bu…
The thermal conductivity of dielectric solids at low temperatures (Theoretical)
Abstract The statistical equilibrium of phonons in the presence of a temperature gradient is investigated, and a general formula for the thermal conductivity of dielectric solids is obtained. This is applied to quartz glass, giving good agreement with values observed by Berman (1951), and to crystals. Comparison betwe…
Recherches sur la cellulose III régénérée de l'ammoniac‐cellulose
Abstract L'étude de la cellulose régénérée des composés de gonflement que fournissent avec NH 3 liquide la cellulose native et la cellulose mercerisée conduit à la définition de deux formes correspondantes aux matières de départ: les celluloses IIIα et IIIβ. L'action de l'eau fournit avec le réseau IIIα un réseau élar…
Conductivity, Hall Effect and Thermo-electric Power of Selenium Single Crystals
Single crystals of selenium have been grown from the vapour phase and their conductivity and thermo-electric power were measured over a range of temperatures. The Hall effect was determined for one crystal. The conductivity obeys a relatively simple exponential law σ = σ 0 exp (- e E / k T ), with e E = 0.13 eV. and t…
Elastoviscous properties of polyisobutylene. IV. Relaxation time spectrum and calculation of bulk viscosity
Abstract The elastoviscous behavior of polyisobutylene may be interpreted in terms of a mechanical model consisting of a distribution of Maxwell elements connected in parallel. The structure of this “generalized Maxwell model” is specified by the distribution of relaxation times of the component elements. The relaxati…
The Oxidation of Oxalate Ion by Peroxydisulfate1
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Oxidation of Oxalate Ion by Peroxydisulfate1Thomas L. AllenCite this: J. Am. Chem. Soc. 1951, 73, 8, 3589–3593Publication Date (Print):August 1, 1951Publication History Published online1 May 2002Published inissue 1 August 1951https://doi.org/10.1021/ja01152a012RIGHTS & P…
Thermal Expansion Properties of Some Synthetic Lithia Minerals
The binary compounds Li 2 O.5Al 2 O 3 and Li 2 O.Al 2 O 3 can be formed easily by reaction of pure materials at 1500°C. The ternary compounds βeucryptite and βT‐spodumene and solid solutions involving these two compounds can be prepared by reaction of Li 2 CO 3 , Al 2 O 3 , and SiO 2 at 1300°C. The thermal expansions…
Calcination Studies of Magnesium Oxides
Magnesium carbonate, basic carbonate, and hydroxide were calcined at temperatures of 300° to 2000°C. for periods ranging from 120 hours at the low temperatures to a few minutes at the higher ones. The resulting magnesium oxides were studied by means of X‐ray powder diffraction and electron and petrographic microscopy.…
LXXXIII. Crystal dislocations.—Elementary concepts and definitions
Summary The elementary concepts of crystal dislocation theory—in particular the Burgers vector, perfect and imperfect dislocations, sessile dislocations, extended dislocations, twin and twinning dislocations—are defined in a manner independent of particular crystal lattices or models or special orientations of the dis…
The spontaneous magnetization of cobalt
Abstract The paper describes how measurements of the spontaneous magnetization of pure specimens of single-crystal close-packed hexagonal and polycrystalline face-centred cubic cobalt have been made over the temperature range -183 to 1121° C. A single crystal of cobalt possessing a close-packed hexagonal structure was…
Neutron Diffraction by Paramagnetic and Antiferromagnetic Substances
Neutron scattering and diffraction studies on a series of paramagnetic and antiferromagnetic substances are reported in the present paper. The paramagnetic diffuse scattering predicted by Halpern and Johnson has been studied, resulting in the determination of the magnetic form factor for ${\mathrm{Mn}}^{++}$ ions. Fro…
Voids and Wax In Solid High-Voltage Cables
A new method of inspection of impregnation of solid-type cable insulation was developed. This method is based on the property of oils and waxes to fluoresce when activated by ultraviolet light. This method reveals details of impregnation in new cables and wax formation in old cables that are not apparent with ordinary…
Removal of Submicron Aerosol Particles from Moving Gas Stream
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRemoval of Submicron Aerosol Particles from Moving Gas StreamP. J. SchauerCite this: Ind. Eng. Chem. 1951, 43, 7, 1532–1538Publication Date (Print):July 1, 1951Publication History Published online1 May 2002Published inissue 1 July 1951https://pubs.acs.org/doi/10.1021/ie50499…
The Relationship Between the Structural Geometry of a Textile Fabric and Its Physical Properties
This paper is primarily concerned with the mechanics of textile fabric abrasion. However, considerable attention is devoted to the theory of friction and the theory of cutting of crystalline solids. This is intended as a framework for the study of visco-elastic fibrous materials. Such an approach seems logical in view…
A New High-Voltage Insulation for Turbine-Generator Stator Windings
This paper reports the development of a new synthetic resin bonded mica tape insulation for high-voltage stator windings. It reviews the problems associated with earlier forms of high-voltage machine insulation. The general construction and processing of the insulation are described briefly. Comprehensive test data ar…