Materials Literature
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Abstract Dolomitic lime samples differing widely in surface activity (specific surface, 5–65 m. 2 g. −1 ) have been ‘dry’ hydrated by exposure to water vapour at 22° and ‘wet’ hydrated by liquid water at 22° and 95°. In general, the calcium oxide hydrates much more rapidly than the magnesium oxide in the dolimes. Duri…
The method of obtaining vibronic selection rules is described for an isolated impurity rare earth or actinidetype ion in a rare earth or actinide salt for various symmetry points of the Brillouin zone. The method is applied to Pr3+ in LaCl3 and the results used to further interpret the vibronic spectrum previously rep…
New ferroelectric tungsten bronze type solid solutions were found with compositions 0.2≤ x ≤0.4 for Sm and La compounds, and x =0.25 for Y compound. The maximum dielectric constants were observed at about x =0.2 for each system, and corresponding Curie points were 278°C, 189°C and 10°C for Y, Sm and La compounds respe…
The complete set of electroelastic constants of a tetragonal lead titanate zirconate ceramic (PZT-5A) is shown as function of the invariant coupling factor ki3 (and, thus, as function of the thoroughness of poling). Interrelations among the important piezoelectric-coupling factors (k33, k31, kp, kt, ki1 = k15, and ki3…
The electrical conductivity and absolute thermoelectric power of AuSb 2 and Cu 2 Sb have been measured between 2.5° and 300 °K. Room-temperature Hall coefficients were also determined. Iron impurity causes a giant diffusion thermoelectric power at low temperatures in the compound Cu 2 Sb, as it has previously been fou…
Abstract Vermiculite (particles 2 to 0.2 microns in diameter), after being treated with H‐Amberlite IR‐120, aged for 97 days, and suspended in 1 N KNO 3 , showed a third buffer range between pH 5.5 and 7.6 on continuous titration with dilute NaOH. This third buffer range is attributed to neutralization of excess proto…
The Mössbauer technique was used to measure the internal magnetic fields and isomer shifts of Fe57 atoms residing at the various sites in the FeAl series. Alloys of Al content varying from 0 to 50 at. % were studied. In the disordered region (<21 at. % Al) five different type sites were observed, corresponding…
A theory of the resistance to extension of nonwoven fabries is calculated on the as sumption that they behave as boaded fiber networks. Early work by Petterson has been generahzed to indude the ettects of fiber curl. which is shown to have a great effect on the value of the initial modulus. There is a good measure of…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDielectric Properties of Alkyl Amides. I. Vapor Phase Dipole Moments and Polarization in Benzene Solution1Richard M. Meighan and Robert H. ColeCite this: J. Phys. Chem. 1964, 68, 3, 503–508Publication Date (Print):March 1, 1964Publication History Published online1 May 2002Pu…
Abstract This study explored the effects of chemical composition, extent of polyesterification and possible side‐reactions upon the rheological behavior of a variety of oil‐modified, glyceryl phthalate alkyds in both melt and in dilute solutions with several solvents. Correlative data were obtained on molecular weight…
Abstract Thirteen aliphatic and aromatic polyhydrazides have been converted as bulk polymer by a unique polymer by a unique polymer post reaction into high molecular weight poly(1,3,4‐oxadiazoles). This reaction proceeds by thermal cyclodehydration at 170–280°C. with elimination of water. The resulting poly(1,3,4‐oxad…
Summary: A membrane surrounding poly-β-hydroxybutyrate (PHB) granules isolated from both Bacillus cereus and B. megaterium has been demonstrated by the carbon-replica technique and electron microscopy. Some general features and properties of both the membrane and PHB granules are discussed.
The effect of various transition metal modifiers on the magnetic properties of iron-rhodium alloys was studied. The exchange inversion temperature Ts, residual magnetization, and maximum magnetization are dependent on the nature of the modifier and on the degree of substitution. As little as 2 at. % of Co, Ni, Cu, Nb,…
Abstract Sorption and fixation of microquantities of Cs by six minerals, as affected by the saturating cations, were studied. Micas and vermiculite sorbed more Cs in the presence of Ca and similar divalent cations than in the presence of K and similar monovalent cations. Montmorillonite and kaolinite, on the other han…
The properly cleaved silicon surface exhibits highly reproducible photoelectric properties, and is known from electron diffraction results to be of high structural perfection. The surface-atom rearrangement that occurs upon heating the cleaved (111) surface to 1000°K in vacuum causes marked changes in the electrical p…
The quantitative cleavage method for determining specific surface energies of solids is subject to several possible sources of error. Some of these are investigated analytically in this study, and a general expression for the surface energy is derived from beam theory for a linearly elastic material. The exact equatio…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDielectric Properties of Alkyl Amides. II. Liquid Dielectric Constant and LossS. J. Bass, W. I. Nathan, R. M. Meighan, and R. H. ColeCite this: J. Phys. Chem. 1964, 68, 3, 509–515Publication Date (Print):March 1, 1964Publication History Published online1 May 2002Published in…
The magnetic structures in FeCr2S4 and FeCr2O4 have been investigated by the powder neutron diffraction technique. From room temperature diffraction patterns, it is established that both compounds are normal spinels with sulfur and oxygen parameters u=0.384 and 0.386, respectively. The FeCr2S4 specimen exhibits a Néel…
The properties and composition of glasses suitable for crystallization of BaTiO 3 are described. The crystallization of certain glasses results in a nearly complete recovery of BaTiO 3 , besides the feldspar BaAl 2 SiO 3 as a minor phase. The mechanism of crystallization was investigated by thermal analysis, viscosity…
Ferromagnetism has been found in several divalent europium compounds. Some of these materials are particularly simple in both crystal and magnetic structure and are ideal for experimental and theoretical study. The materials we have investigated can be divided into three groups, europium chalcogenides, europium haloge…