Materials Literature
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Results on dielectric polarization and its variations in strong electric fields are presented for solutions of hexanol-1 in hexane, benzene, 1,4-dioxane, and triethylamine. A method for calculating the dipole moments of multimers and complexes on the basis of experimental results is proposed. Also, the concentrations…
Powder x-ray-diffraction studies on tellurium up to 150 kbar show only two structural transitions at 40 and 70 kbar in agreement with Bridgman's work. The structure of the 40–70-kbar phase is unsolved. Above 70 kbar, it is proposed that tellurium is isomorphous with β-polonium and is rhombohedral with a=3.002±15 Å, α=…
Normal frequencies of crystalline polymethylene have been calculated for various phase differences along the c axis of the crystal. Intermolecular hydrogen—hydrogen force constants have been evaluated from the splitting of the spectroscopically active modes. The results of the calculations explain almost satisfactoril…
Abstract Morphology and kinetics of the spherulite crystallization has been studied for d,l ‐poly‐(propylene oxide) ( d,l ‐PPO) (M̄ n = 135,000) and l ‐PPO (M̄ n = 10,300). Both polymers have similar physical characteristics except that d,l ‐PPO normally gives non‐ringed spherulites whereas l ‐PPO exhibits the ringed…
The principal absorption bands induced by irradiation at liquid-helium temperature with x rays in CsBr crystals are the complex $F$ band and two overlapping $V$ bands at 435 and 497 m\ensuremath{\mu}. In view of the dichroic properties of these $V$ bands, the most obvious model seems to be a ${\mathrm{Br}}_{2}^{\ensur…
The thermoelectric power of Cu-Al and Cu-Si alloys has been determined from 4.2 to 320\ifmmode^\circ\else\textdegree\fi{}K. Assuming that the thermopower is separable into diffusion and phonon-drag components, the change in phonon-drag thermopower $\ensuremath{\Delta}{S}_{g}$ is determined for Cu+0.77 at.% Al and Cu+1…
The electronic band structure of ordered beta brass (${\ensuremath{\beta}}^{\ensuremath{'}}$ CuZn) has been calculated from first principles by the Green's-function technique. Two slightly different crystal potentials of the muffin-tin type have been tested, both based on free-atom Hartree-Fock wave functions. Each po…
The experimental results of phonon-drag thermoelectric power of $n$-InSb are analyzed to obtain information about electron-phonon and phonon-phonon interactions. We find that for temperatures greater than 6\ifmmode^\circ\else\textdegree\fi{}K, the piezoelectric mode of electron scattering is negligible as compared to…
The data of Allen and Gobeli on photoemissive yields from partially cesiated surfaces of several semiconductors with photon energies between 2 and 6 eV are analyzed in detail. The results are shown to be consistent with direct transitions in energy-band models obtained from semiempirical pseudopotentials based on inte…
An elementary analysis is given of the conditions for phase transformations of the first and second orders, in the molecular-field approximation. The analysis may be relevant to some ferroelectric, Jahn-Teller, order-disorder, and singlet-triplet transitions. On the assumptions of our two-level model, no transition ca…
X-ray diffraction powder patterns taken at high pressure suggest by analogy to Gd that Tb, Dy, and Ho have first-order transitions from a hcp to a Sm-type structure at high pressure. The $\frac{c}{a}$ ratio of the hcp phases increases with pressure toward the ideal value. The change of the Curie or N\'eel temperature…
Various kinds of clay minerals mixed with calcium carbonate and ammonium chloride were heated at a specific temperature in the range of 500-1000 degrees C. for one hour, and the reaction products were examined. The kinds of reaction products depend upon the chemical compositions of the clay minerals. In the case of cl…
Values of the enthalpy of dehydration determined by difierential thermal analysis are 151, 156 and 160 cal/gm for kaolinite, dickite and halloysite respectively. Activation energies for dehydration at a water pressure of 15 psi are consideratrly greater than published activation energies determined at much lower water…
The solubility of helium in uranium dioxide was calculated directly from atomic properties and compared with experiment. The calculations were based upon a statistical-mechanical formula which assumes dissolved helium to behave as a simple harmonic oscillator in an interstitial site in the UO2 lattice. Knowledge of th…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAqueous Sodium Borohydride Chemistry. The Colnage Metals, Copper, Silver, and Gold.L. F. Hohnstedt, B. O. Miniatas, and Sr. M. Concetta. WallerCite this: Anal. Chem. 1965, 37, 9, 1163–1164Publication Date (Print):August 1, 1965Publication History Published online1 May 2002Pu…
Gold films have been vacuum deposited onto quartz substrates in a temperature range from 5° to 750°C. Films which are deposited below about 50°C exhibit decreases in reflectivity of up to 25% over bulk values. Associated with this decrease are large increases in resistivity and near amorphous x-ray diffraction pattern…
Tensile and fatigue tests have been performed on zinc single crystals oriented with the basal plane parallel to the stress axis. In tensile tests twinning occurred at lower stresses at 20 or 77°K than at room temperature. {1122} slip, which had preceded twinning, was prominent on room temperature specimens, but was ob…
If a textile yarn, marked at intervals along its length, is struck transversely by a rifle bullet, a flash photograph taken shortly after impact will reveal a shifting of the marks caused by passage of a strain wave. Analysis of these shifts provides data on the dis tribution of strain and strain velocity in the wave.…
The reststrahlen reflectance of crystalline materials can be enhanced with coatings of nonabsorbing interference films. At the same time the reflectance curve is altered to be nearly rectangular in shape as is more appropriate for infrared reflection filtering. The coatings consist of single films or are designed arou…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCalculation of the Hall Effect in Ionic Solutions1aHarold L. FriedmanCite this: J. Phys. Chem. 1965, 69, 8, 2617–2628Publication Date (Print):August 1, 1965Publication History Published online1 May 2002Published inissue 1 August 1965https://pubs.acs.org/doi/10.1021/j100892a0…