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The approximation is made that the dividing surface between a liquid and its vapor phase is a monomolecular layer, in which a molecule has a free volume larger than for an interior molecule and a potential energy less than for the latter. By introducing the approximation into the significant structure theory of liquid…
The effect of configuration interaction on the validity of the usual method of expanding the crystal field potential in terms of spherical harmonics is examined using second-order perturbation theory. It is found that for a configuration of equivalent electrons lN most mechanisms of configuration interaction lead to a…
The release of hydrogen atoms by a platinum surface in contact with molecular hydrogen occurs if there is oxygen in the system. In particular, it is sufficient that the oxygen be adsorbed at the surface of the metal.
The shell of the freeswimming veliger larval stage of the common North American oyster Crassostrea virginica (Gmelin, 1791) is composed of aragonite. This composition contrasts with that of the adult shell, which is composed mainly of calcite, the rhombohedral allomorph of calcium carbonate, and minor amounts of arago…
Abstract Several features of the pyrolysis of acetylene in the temperature range 500 to 1000 °C suggest that the underlying mechanism is the same as that in operation at both lower and higher temperatures. Thus the rate of consumption of acetylene obeys a second-order kinetic law and is little affected by additions of…
The Overhauser shift of the electron spin resonance due to the natural nuclear polarization at liquidhelium temperatures has been used to measure the conduction-electron density at the nuclei in $n$-type InSb. The results are: ${|\ensuremath{\psi}({R}_{\mathrm{In}})|}^{2}=(9.35\ifmmode\pm\else\textpm\fi{}1)\ifmmode\ti…
The salient feature of the splittings of the crystalline levels of a rare-earth ion in the iron garnets is the difference of their anisotropy from that of the $g$ tensor for the Zeeman effect. This additional anisotropy arises from the dependence of the rare-earth-iron (RE-Fe) exchange interaction on the orbital state…
The anisotropy of the magnetic hyperfine interaction in ferromagnetic Zr${\mathrm{Fe}}_{2}$ has been demonstrated with the M\"ossbauer effect. It is suggested that such anisotropy is responsible for the failure to observe domain-wall enhanced NMR in similar materials. It may also account for the failure to detect the…
The rates of hydrogen penetration through single iron crystals in contact with an H2S-CO2-H2O environment were related to the specific crystallographic orientation of the crystals using a novel, highly reliable penetration cell. The rate of hydrogen penetration was shown to be a function of the lattice packing density…
In estimating the nucleation field of an infinite rectangular bar, Aharoni used a variational method to calculate a lower bound to the magnetostatic energy. He constrained the variable potential to a specified form inside an ellipse circumscribed about the rectangle. In the present article, the method is improved by i…
Polymorphic transitions in CasSiO 6 have been investigated by precise high‐temperature X‐ray diffractometer measurements and by differential thermal analyses. In addition to change caused by normal thermal expansion, three principal crystallographic transformations take place: α‐triclinic–β–triclinic (sluggish) in the…
Abstract The memory of irradiated polyethylene has been studied with emphasis on the magnitude of the restoration force exerted by the deformed polymer during the process of restoration to the nonstressed state and on the degree of completeness with which restoration occurs. The particular form of the memory effect st…
Abstract Measurement of butadiene absorption at constant volume, and of polymer formation, indicated that the rate of polymerization was first order in monomer concentration, up to 1.5 mole/l., and also in initial total catalyst concentration, for given molar ratio of alkyl to titanium ester. The overall activation en…
Abstract Soils having different values of permanent charge (CECp), variable charge (CECv), and anion‐exchange capacity (AEC) were treated with hydroxyl, sulfate and hydrogen saturated exchange resins. The AEC was then principally OH ‐ or SO 4 2‐ saturated while CECp was principally saturated with aluminohydronium and…
Abstract The infrared active normal vibrations of isotactic polypropylene and its deuterated derivatives in the crystalline state have been treated. The modified Urey-Bradley-Shimanouchi force field has been used for the calculations. A total of 23 potential constants have been adjusted by the method of least squares…
Abstract The rate of crosslinking of concentrated gelatin solutions in water has been measured by means of a gelation timer. Some effects of temperature, pH, crosslinking agent, and gelatin concentration have been measured. The crosslinking agents have varied from fast‐acting chrome alum, glutaraldehyde, and a carbodi…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThermodynamics of Aqueous Solutions of Hydriodic Acid from Electromotive Force Measurements of Hydrogen-Silver Iodide CellsHannah B. Hetzer, R. A. Robinson, and Roger G. BatesCite this: J. Phys. Chem. 1964, 68, 7, 1929–1933Publication Date (Print):July 1, 1964Publication His…
Abstract The thermal decomposition of the C 4 , C 6 , and C 8 polymethylene sulfones has been investigated at 275°C. under reduced pressure. The gaseous decomposition products, collected and identified by infrared and mass‐spectrometer analysis, were found to consist primarily of sulfur dioxide, olefins, alkanes, wate…
Electron beams of approximately 2 kW power and acceleration voltages in the range about 100 kV are focused on metal surfaces in spots of 15 to 250 μ so that maximum power densities of more than 1013 W/m2 can be achieved. Such electrons penetrate several orders of magnitude deeper into the solid or liquid materials tha…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDithiolium Derivatives. I. 2-Dialkylamino-1,3-dithiolium Perchlorates1E. Campaigne and N. W. JacobsenCite this: J. Org. Chem. 1964, 29, 7, 1703–1708Publication Date (Print):July 1, 1964Publication History Published online1 May 2002Published inissue 1 July 1964https://pubs.ac…