Electron Correlations at Metallic Densities
free path 1(k) will be parallel to k, and hence one may write 1 =7~V, OH 'e(rd ~/m )/(~d&')
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Determination of D(AlO) from Crossed-Beam Chemiluminescence of Al + O3
In a molecular beam apparatus, a thermal beam of aluminum atoms (≈ 1700°K) intersects an uncollimated thermal beam of ozone molecules (300°K) and the resulting visible chemiluminescence is recorded with a 1 m scanning monochromator. The chemiluminescence spectrum consists of (1) the AlO B 2Σ+−X 2Σ+ blue-green system f…
Raman Scattering, Luminescence, and Exciton-Phonon Coupling inCu2O
Raman scattering and exciton luminescence and absorption have been studied in high-purity single-crystal ${\mathrm{Cu}}_{2}$O at liquid-helium temperature using 4880-\AA{} laser excitation. The Raman-active mode has been unambiguously identified at 515 ${\mathrm{cm}}^{\ensuremath{-}1}$, and the first observation made…
Electron Scattering from Surface Excitations
Surface modes play an important role in a solid's response to external disturbances. A charged particle on approaching or leaving the surface may suffer inelastic scattering owing to its coupling with these modes. The scattering rate is calculated in the Born approximation for two instances: (i) in metals, where the s…
Effect of the 110°K Phase Transition on the SrTiO3Conduction Bands
The linear-combination-of-atomic-orbitals (LCAO) model of the preceding paper for the cubic-SrTi${\mathrm{O}}_{3}$ band structure is applied to predict the effect of the 110 \ifmmode^\circ\else\textdegree\fi{}K phase transition on the SrTi${\mathrm{O}}_{3}$ conduction bands. In this cubic-to-tetragonal structural tran…
Transport Properties of Semiconducting Phosphate Glasses
The temperature and frequency dependence of conductivity, dielectric properties, infrared absorption, and electron-paramagnetic-resonance data are presented for semiconducting phosphate glasses based on oxides of Ti, V, Mn, Fe, Co, Ni, Cu, Mo, and W. The vanadate system is examined in a range of compositions, most of…
Energy Bands for KNiF3, SrTiO3, KMoO3, and KTaO3
The nonrelativistic augmented-plane-wave (APW) method has been applied to calculate the electronic band structures for several cubic perovskite-type compounds, including KNi${\mathrm{F}}_{3}$, SrTi${\mathrm{O}}_{3}$, KMo${\mathrm{O}}_{3}$, and KTa${\mathrm{O}}_{3}$. These calculations involve ad hoc crystal potentials…
Orienting Action of Sound on Nematic Liquid Crystals
A theory is outlined of the aligning action of sound on nematic liquid crystals. It is based on sound-induced stresses and forces and identifies four contributions to the transverse stress. Formulas for the threshold sound intensities of a few simple deformations are given.
Fission-track stability in volcanic glass of different water contents
Experiments to reveal the influence of water concentration in obsidian upon the annealing rate of fission tracks showed that a 2.2% H2O obsidian would lose 70% of its tracks in 1 m.y. if held at 30°C. Data obtained at three temperatures (227°, 253°, and 282°C) give the possibility of extrapolations to geologically sig…
A Method of Calculation on a Step Cascade with Side Flow for Enriching Uranium
The step cascade with side flow is defined as a step cascade where uranium of lower assays than that from the final stage is withdrawn, and where also, in addition to the major feed, reprocessed spent uranium is introduced as minor feed. A method of calculation is proposed for finding the exact total flow rate of the…
Acid character of nontronite: permanent and pH-dependent charge components of cation exchange capacity
Abstract The cation exchange capacity (C.E.C.) of nontronite was determined by titrating the acid clay, prepared by the action of H-resin on nontronite, in water and some nonaqueous solvents. The base-titratable acidities of the acid nontronite, freshly prepared as well as aged, were found to be greater than the acidi…
Vapor Pressure and Heat of Vaporization of Cobalt
New vapor pressure data for cobalt have been obtained in the temperature range 1519–1926°K from Knudsen effusion experiments. The derived third-law heat of vaporization of cobalt is Δ H298°=101.0± 0.6 kcal/mole. Plausible explanations are presented that account for the widely differing vapor pressure data and heats of…
Apatite, monazite and allanite; three rare earth minerals from Korsnäs, Finland
In the AE-bearing lead deposit of Korsns, apatite is the most common REmineral, monazite is a widespread accessory and allanite is a rare constituent. The paper describes one type of each. Also, the physical properties and chemical composition of the minerals are presented. The chemical analyses contain determinations…
Dispersion of the stress-optic coefficient in glasses
The stress-optic coefficient ( n 3 /2)( q 11 - q 12 ) has been determined for a series of 18 optical glasses of different compositions in the wavelength range 5700-3200 Å. The coefficients are negative for all the glasses except for a high-lead-content glass of density 6·7 and refractive index 1·89. The numerical valu…
Die Struktur des Sanidins bei verschiedenen Ordnungsgraden
The influence of heat treatment on the Si,Al-distribution in a sanidine of Volkesfeld, Eifel, was investigated by two complete crystal-structure analyses. Observed differences in the mean T–O distances are compared with simultaneous changes of the optic axial angle and give additional data to such correlations first p…
Kinetics of the UO 2 ‐C‐N 2 Reaction at 1700°C
The mechanism of the reaction of UO 2 with carbon in the presence of N 2 at 1700°C and the rate of formation of the carbonitride product were determined. Uranium carbonitride forms at specific O 2 and N 2 chemical potentials by reactions such as (1) UO 2 ( s ) + 0.67HCN( g )→UO 1.33 N 0.45 ( s ) + 0.67CO( g ) + 0.11N…
Raman Effect in Selenium–Tellurium Mixed Crystals
Abstract The Raman effect in selenium–tellurium mixed crystals has been studied. Four first order Raman lines have been observed and associated with long wavelength lattice modes of the alloy system. The experimental results together with existing infrared data indicate that the long wavelength modes from three of the…
Electron probe microdetermination of carbon in ferrous alloys
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectron probe microdetermination of carbon in ferrous alloysJ. S. Duerr and R. E. OgilvieCite this: Anal. Chem. 1972, 44, 14, 2361–2367Publication Date (Print):December 1, 1972Publication History Published online1 May 2002Published inissue 1 December 1972https://pubs.acs.or…
A 13C Nuclear‐Magnetic‐Resonance Study of the Enzyme Cofactor Flavin‐Adenine Dinucleotide
An assignment of the 13 C‐NMR spectrum of the enzyme cofactor flavin‐adenine dinucleotide (FAD) is given by comparing it with the 13 C chemical shifts of the constituents of FAD, i.e. adenosine 5′‐diphosphate, riboflavin 5′‐monophosphate, riboflavin, adenosine and adenine. The 13 C‐NMR spectrum of FAD shows three grou…
Energy Levels of Er3+ in Three Rare Earth Hydroxides
Energy levels of Er3+ in three compounds: Er(OH)3, 1% Er3+:Y(OH)3, and 1% Er3+:Tb(OH)3 have been determined from optical absorption experiments on single crystals at 77 and 1.3°K and from far infrared absorption experiments at 1.3°K. For each material, the four crystal field parameters which specify the crystal field…