bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some Calculations Concerning the Pseudo-Kikuchi Pattern Contrast from Tilted Crystals
Authors: Pirouz P. 
Published: February 2015

The theory of Hirsch und Humphreys1 has been applied to calculate the contrast across pseudo-kikuchi bands for tilted crystals. The crystallographic planes giving rise to the pattern are assumed to lie parallel to the undeflected electron beam. An asymmetry in contrast across individual bands is found, in agreement with experimental observations.
Intensity profiles and simulated patterns for several angles of tilt in the case of the undeflected beam perpendicular to the (111) reciprocal latice plane of a silicon crystal are presented.
Millimeter Wave Rotational Transitions of 16O12C32S and 16O13C32S
Authors: Larsen N. W. , Winnewisser B. P. 
Published: February 2015

Rotational transitions of 16012C32S and 16013C32S in the ground vibrational state and of 16012C32S in several excited states have been accurately measured in the millimeter wave region for a minimum of four different J values. The analysis of the measured frequencies leads to rotational constants for the following vibrational states:
0 00 0 of 16O13C32S and
0 00 0, 0 1 1c 0, 0 1 1d 0, 0 20 0, 0 22c 0, 0 22d 0,
0 00 1 of 16O12C32S.
Since the two components of the 0 22 0 transitions were resolved, an analysis of the l-type resonance was carried out and the interval 0 22 0 - 0 20 0 has been determined to be -4.63(10) cm-1. The result is in good agreement with the presently available determination of this level from vibrational spectra.
Reaktionskinetische Untersuchungen an neutronenbestrahlten Alkalihalogenid-Einkristallen / Reaction Kinetic Investigations in Neutronirradiated Alkalihalide Single Crystals
Authors: Felix F. W. , Meier K. , Müller M. 
Published: February 2015

It is often observed that the isothermal degassing of the systems KCl/Ar, CsBr/Xe, and CsJ/Xe cannot be described by Fick's law. According to the diffusion model of Hurst and Gaus one can interpretate such deviations by assuming a reaction of first order between rare gas atoms and lattice defects. This model explains qualitatively several experimentally observed phenomena very well.
A quantitative interpretation of the obtained results, however, leads to contradictions.
Molecular g-Values and Magnetic Susceptibility Anisotropy Parameters of D2-Ketene. Sign of the Dipole Moment of Ketene
Authors: Sastry K. V. L. N. , Guarnieri A. 
Published: February 2015

Abstract
The rotational Zeeman-effect of D2CCO has been observed under high resolution. In addition to g-factors and susceptibility anisotropics the sign of the electric dipole moment has been determined after having remeasured the same parameters for normal ketene under identical conditions.
Mean Amplitudes of Vibration for Tetrahedral Molecules and Ions
Authors: Sharma D. K. , Pandey A. N. , Dublish A. K. , Rai S. N. 
Published: February 2015

Abstract
Mean amplitudes of vibration for 38 tetrahalides and 15 tetraoxides have been computed at temperatures T = 0° K , T = 298.15 °K and T=500°K employing most recent vibrational data. Müller's method has been followed in solving the two dimensional Cyvin's secular determinant. The results have been briefly discussed.
Über die doppelbrechende Phase der Mischkristalle von NH4Br mit TIBr. NH4Br mit CsBr und NH4Cl mit CsCl
Authors: Brauer Peter 
Published: February 2015

Abstract
The range of existence of the birefringent tetragonal phase of mixed crystals of NH4Br or NH4Cl and other isomorph halides with the same anion is being examined. Especially, it will be shown that by adding CsCl even NH4Cl can be caused to change into that phase, i. e. to behave qualitatively like NH4Br.
Temperature Dependence of the Work Function of Nickel
Authors: Christmann K. , Ertl G. , Schober O. 
Published: February 2015

Abstract
The variation of the work function of nickel with temperature was measured with clean (111) and (100) surfaces between 25 and 320 °C and up to 430 °C with Ni(110). In all cases the work function decreases linearly with temperature by 1.7 x 10-4 eV/°C. No anomaly (neither a jump nor a change of the slope dφ/dT) was found at the Curie point.
Kernresonanzuntersuchung der Molekülrotation in festem Benzol: T1-Spektroskopie / Nuclear Magnetic Resonance Investigation of Molecular Rotation in Solid Benzene: T1-spectroscopy
Authors: Wendt J. , Noack F. 
Published: February 2015

We have extended Haeberlen’s and Maier’s NMR investigation of the molecular rotation in solid polycrystalline benzene (C6H6), performed in 1967 in the Larmor frequency range from 88 MHz to 22 MHz, to lower frequencies down to 4.4 MHz. In some cases monocrystalline samples were also studied. The extensive data show that the presently accepted model of purely uncorrected rotations of the benzene molecules around their sixfold axis has to be rejected. Instead, two results found, namely
- a slight increase of the rotational activation energy when approaching the melting point of benzene and
- the width of the T1 relaxation minima as a function of the reciprocal temperature suggest an additional relevance of correlated molecular motions, like e.g. the ‘gear-wheel mechanism’ first proposed by Cox. By appropriate modifications of Haeberlen’s theory, i.e. by assuming a rate equation with temperature dependent activation energy and by emphasizing the effect of simultaneous rotations of neighbouring rings compared with the purely statistical, uncorrelated case, we succeeded to describe the considered T1 measurements quantitatively.
Population Densities and Ionization Coefficients of Fast Transient Hydrogen Plasmas
Authors: Cacciatore M. , Capitelli M. 
Published: February 2015

Abstract
Population densities and ionization coefficients of transient hydrogen plasmas have been calculated for typical ionization and recombination conditions. The results have been obtained by solving a system of differential equations by means of the Runge-Kutta method. Each equation describes the temporal evolution of a quantum state belonging to the plasma. Two initial conditions have been studied: i) The number density populations of the excited states are in Saha equilibrium with the electrons ii) the densities of excited states are equal to zero, whereas the initial condition for the ground state density is caracterized by a non-equilibrium parameter b1(t = 0) =n1/n1E > which has been varied from 106 to 10-2. Typical results for electron number densities ne ranging from 108 to 2.5 · 1013 p/cm3 and electron temperatures ranging from T = 8000 to 16000 °K are presented and discussed.
Internal Cation Mobilities in the Molten Systems LiNO3-TlNO3 and RbNO3-TlNO3
Authors: Kawamura Kazutaka , Okada Isao , Odawara Osamu 
Published: February 2015

Abstract
The relative differences in internal cation mobilities are measured for the molten systems LiNO3-TlNO3 and RbNO3-TlNO3 over a wide range of temperature and concentration by means of counter-current electromigration technique (Klemm's method), and the internal mobilities are calculated from the existing data on the electric conductivity for these systems. For the system LiNO3-TlNO3 , a marked dependence of the relative internal mobility differences on temperature is found particularly in the Li+ rich region, and a considerable concentration dependence is found over the investigated temperature range. This is qualitatively explained in terms of a model which takes into account mainly the differences of the cation-anion pair potentials and of the sizes of the two cations. On the other hand, for the system RbNO3-TlNO3, only a slight temperature dependence is observed and no concentration dependence, if present, is detected within the experimental accuracy.
Isotope Effect of Cation Electromigration in Molten Lithium Chloride-Nitrate-Mixtures
Authors: Ljubimov Vladislav , Lundén Arnold 
Published: February 2015

Abstract
Molten mixtures of lithium chloride and nitrate, including the decomposition products nitrite and oxide, were electrolysed at about 600 °C with gaseous electrodes. The relative mobilities of the lithium isotopes were studied. The mass effect (relative difference in mobility divided by relative difference in mass) is 0.063 for a mixture with 20% Cl- and 0.069 for 80% CI-, which both are more than 30% smaller than those interpolated from the isotope effects of pure LiNO3 and LiCl. It is concluded that the lithium ions interact more strongly (with the anions and/or with each other) in a melt containing several anions than in a pure melt. The experiments also yield some information about the mobilities of the anions present in the melt.
The Density at 25 °C of D2O with Natural Oxygen Isotopic Composition
Authors: Babeliowsky T. , Brulmans J. 
Published: February 2015

Abstract
In measuring the influence of oxygen isotopic composition and of hydrogen content on the density of heavy water an extrapolation was made to 100% D2O with natural oxygen isotopic composition, starting with the density of a highly enriched heavy water (99.95% D2O, about natural oxygen isotopic composition).
A value of 1104.481 kg/m 3 at 25 °C was obtained.
Thermal Expansion of Heavy Water between 7 and 26 °C
Authors: Brulmans J. , Verdonck J. , Eschbach H. L. 
Published: February 2015

Abstract
Using six carefully calibrated quartz floats the thermal expansion of water with a D2O content of 99.74 mole % has been measured between 7 and 26 °C. The extrapolation to 100% D2O with natural oxygen isotopic composition is made.
Waldmann-Snider Collision Integrals and Nonspherical Molecular Interaction
Authors: Köhler W. E. 
Published: February 2015

Abstract
The binary scattering amplitude matrix is derived from the general interaction potential between linear molecules. The first order distorted wave Born approximation (DWBA) is used which is applicable for small nonsphericity of the interaction. The molecular cross sections determining the most important Waldmann-Snider collision integrals are calculated. In particular, the scattering cross section, the orientation cross sections for vector-and tensor polarization and the reorientation cross sections for the tensor polarization of the rotational angular momenta are treated. For a simple interaction model for HD (HT) molecules the DWBA-scattering amplitude is evaluated analytically. The relaxation cross section of the tensor polarization, σT , and the coupling cross section of friction pressure tensor and tensor polarization, ση,T, are calculated for room temperature and compared with experimental values.
Gamma-Ray Induced Luminescence of Silica Gel
Authors: Kirmaier P. , Rabe J. G. 
Published: February 2015

Abstract
The thermoluminescence glow curve of γ-irradiated silica gel investigated between 77 °K and 600 °K is a broad band extending from 80 °K to ~ 400 °к. The emission occurs at ~ 450 nm. Shallow traps (0.1 - 0.2 eV) are responsible for most of the light emitted. The distribution of trap depth and the increase of trap density toward the band edge is tentatively attributed to the dis-ordered structure of silica gel in accordance with previous suggestions concerning glasses. In contrast to the growth with radiation dose of color-and paramagnetic center concentration, luminescence is already saturated at about 1 Mrad. The luminescence decay follows the hyperbolic relation derived by Adirowich for a bimolecular process in the case of retrapping for which evidence is presented. At very low radiation doses the initial intensity of luminescence was proportional to the square of the dose rate as expected for a bimolecular reaction.
Removal of surface OH groups as accomplished by raising the degassing temperature of the gel results in an increase of luminescence intensity by several orders of magnitude. Hydrogen and oxygen when adsorbed prior to or subsequent to irradiation reduce the luminescence intensity to about one per cent of that observed in vacuum or in the presence of helium. The results are dis-cussed in terms of surface reactions involving free and trapped charge carriers generated during irradiation.
Ein Beitrag zur Radiofrequenz-Mikrowellen-Doppelresonanz-Methode / A Contribution to the Radiofrequency Microwave Double Resonance Method
Authors: Schwarz R. , Dreizier H. , Guarnieri A. 
Published: February 2015

Abstract
Experiments are reported which extend the useful Radiofrequency Microwave Double Resonance Method to higher Radiofrequencies. A special absorption cell was constructed for this purpose.
Third Virial Coefficients for Ar, Kr, and Xe Including Nonadditive Effects
Authors: Caligaris R. E. , Scalise O. H. , Grigera J. R. 
Published: February 2015

Abstract
In this work we adopt the RMMV potential function proposed by Davis and calculate third virial coefficients for Ar, Kr, and Xe. Nonadditive effects due to dipole-dipole-dipole and dipole-dipole-quadrupole terms are included. We found good agreement between theoretical and experi-mental values for Ar and Kr, but not for Xe.
Adiabatische Invarianz im Mittel / Adiabatic Invariance in the Average
Authors: Janicke L. 
Published: February 2015

Abstract
We study the possibility to construct an adiabatic invariant for charged particles in electromagnetic fields, that vary strongly in space but only slowly in time (measured by a small parameter ε). We specialize to those fields, where the motion of the particle is described by a Hamiltonian that corresponds to a one-dimensional oscillator with a potential exhibiting two minima. This type of potential can occur in the case of one-dimensional fields with neutral sheets. The action integral I=∮ p dq is no longer an adiabatic invariant for particles with an energy near the value of the inner maximum of the potential, nor is it a continuous function of the energy. The second difficulty can be removed by proper redefinition. Then by using the area conservation in the phase plane it can be shown that for any arbitrary particle ensemble in the phase plane of the one-dimensional oscillator the mean value of the action integral is adiabaticly invariant to order ε ln4 ε. Under certain circumstances it can happen that a coherent ensemble splits up into two separated groups. It will be shown that this also can be understood essentially as an adiabatic process.
Test of the Unitary Pole Approximation to the Malfliet-Tjon Potential for Elastic Neutron-Deuteron Scattering
Authors: Ziegelmann H. 
Published: February 2015

Abstract
The quality of the unitary pole approximation to the soft-core Malfliet-Tjon potential is demon-strated for elastic neutron-deuteron scattering above breakup threshold.
The Influence of Deviations from the Maxwellian Electron Distribution on the Population densities in a low Temperature Monatomic Plasma
Authors: Claaßen H. A. 
Published: February 2015

Abstract
A selfconsistent solution with respect to both free and bound electron energy states is presented for a low temperature monatomic plasma. The deviations from a Maxwellian electron distribution under the action of unbalanced resonance transitions of the plasma atoms are incorporated in analytical form using a recursion formula, which links the high energy tail of the electron distribution function to its low energy part. The unbalance of the resonance level may be due to diffusion processes and/or radiation escape, which reflect the influence of the plasma boundaries. The population densities of the bound electron energy states are numerically determined by an iteration procedure. The calculations were performed for a cesium plasma both without and with consideration of resonance level diffusion and ambipolar diffusion. As is to be expected, the effect of a disturbance of the electron distribution on the population densities increases with decreasing electron density and increasing electron temperature.
Zur allgemeincn Formulierung der Fliefibedingung unter Beriicjisichtigung der Anisotropie und des Bauschinger-Effektes / On the general Formulation of Yield Conditions under Consideration of Anisotropy and Bauschinger-Effect
Authors: Troost A. , Betten J. 
Published: February 2015

Abstract
In this paper, some aspects of the isotropic and anisotropic yield conditions are discussed on the base of the plastic potential by introduction of partial potentials. The significance of the Bauschinger-Effect is investigated, in order to describe the mechanical behavior of materials in which the magnitude of the uniaxial yield strength depends on the sign of stress. This generalized concept is successfully applied to titanium sheets. The theory is compared with experimental results.
Preparation and Superconducting Properties of Niobium Carbonitride Wires
Authors: Bernhardt K.-H. 
Published: February 2015

Abstract
Superconducting niobium carbonitride wires Nb(CyNx) has been prepared by a diffusion process in two steps, first diffusing carbon from methane into niobium wires and then nitrogen into these carbonized samples. The optimum conditions for these preparations have been investigated in detail. All samples have been analysed quantitatively for C, N and Nb. The carbonizing as well as the following nitriding of the wires has been investigated under various conditions. The maximum of the transition temperature of the Nb(CyNx) wires prepared by this two steps diffusion process is reached for the same composition y, x as for sintered samples. But the value is about 0.4 K lower.
Analysis of the Relaxation of Wall Electrons in a Plasma
Authors: Ecker G. , Riemann K.-U. , Scholz A. 
Published: February 2015

Abstract
A procedure is developed which renders the simultaneous description of angular and energy relaxation of wall electrons in a plasma possible. The plasma is assumed to be field free, allowance is made for elastic and inelastic collisions with neutrals, as well as for electron-electron encounters. The procedure is based on an expansion in terms of the eigenfunctions of a suitable part of the kinetic equation. In the zeroth order, the problem is reduced to a boundary value problem of the Sturm type, and subsequent solution of a singular integral equation by standard technique. To account for the rest of the kinetic equation, we construct a Green′s function which forms the basis for an iteration process. The application of the procedure is illustrated with an example.
Messung der Krypton-85-Aktivität der atmosphärischen Luft / A Method for Measurement of the Krypton-85-content in the Atmosphere
Authors: Stockburger H. , Sittkus A. 
Published: February 2015

Abstract
To measure the Kr-85 content in the atmosphere we developed a simple method. Within a time internal of five to ten days (depending on the moisture of the air) five to ten m 3 of air (NTP) are pumped through activated carbon (pressure 300 torr, temperature 77 °K). When sampling time is over, the carbon is heated to 470 °K. This gives a gas sample of 4 1 with more than 90% of the atmospherical krypton in 3 hours. With a further step of enrichment, the volume of the sample is reduced to 100 ml. The final separation of krypton from O2 , N2 , CO, CO2 and Xe is made by gaschromatography at room temperature with methane as eluent gas (duration 25 min). The Kr-fraction is transported to a proportional counter (200 ml). The overall yield is 90%. The overall error of the Kr-85 content is near 1%. Data are given for the time of 15. 6. 1973 to 29. 12. 1974.
Kosmogener Überschuß von 40K und Fluß schneller Neutronen in Meteoriten / Cosmogenic Excess of 40K and the Flux of Fast Neutrons in Meteorites
Authors: Stegmann W. , Begemann F. 
Published: February 2015

Abstract
Results are reported of a mass spectrometric investigation of the content and isotopic com-position of potassium from the mesosiderite Emery (silicate phase) and the chondrite Elenovka (bulk). Normalized to the Nier value of 39 K/ 41 K=13.47 the 40 K in Emery (K-content 220 + 25 ppm) was found to be enriched by (4.03 ± .30)%, the potassium from Elenovka (760 ± 50 ppm) to be indistinguishable from terrestrial potassium. - Evidence is presented that the excess 40 K in the silicates from Emery (Ca-content 6.06 weight %) has been produced essentially by secondary cosmic ray neutrons via the 40 Ca (n,p) -reaction. The total excess of (2.57 ± .39) x 1014
40 K-atoms/g Ca together with the excitation function of the 40 Ca (n,p) -reaction and the neutron flux spectrum of Arnold, Honda and Lal yields a dose of fast neutrons (2 MeV ≦ En ≦ 100 MeV) Φ · T = (7.2 ± 1.1) x 1016 neutrons /cm2 and an average flux during the cosmic ray exposure age T = (134 ± 12) Myrs of Φ = (17.4 ± 3.1) neutrons /cm2 sec. - A comparison of the neutron induced production rate of 40 K from Ca with that of 21 Ne from Mg and 38 Ar from Ca indicates the Arnold, Honda, Lal flux spectrum to be adequate for En ≲ 20 MeV but that it underestimates the number of neutrons with higher energies.
Mögliche Deutungen quadratischer Fließbedingungen bei Isotropie und Anisotropie / Physical Interpretations of Isotropic and Anisotropic Yield-Conditions
Authors: Troost A. , Betten J. 
Published: February 2015

Abstract
The paper introduces shear stress quantities, which are the difference of two stress tensors, the actual one and one produced by rotating the axes. This quantities have physical significance. In the vectorial representation in the principal stress space and the principal shear stress space the paper give some interesting relations. The authors observe that Hill′s anisotropic yield criterion can be derived from their shear stress quantities by introducing a measure tensor and gave a physical explanation to Hill′s condition.
An ab initio Calculation of the Force Constants, Vibrational Frequencies, and Equilibrium Geometry of HCP
Authors: Botschwina P. , Pecul K. , Preuss H. 
Published: February 2015

Abstract
All the harmonic, the diagonal cubic and quartic stretching and the semidiagonal cubic force constants of HCP have been calculated from Hartree-Fock wavefunctions by the force method of Pulay. The force constants are in good agreement with the experimental ones, except for FRR, Faa, FRr, FRaa, and Fraa the latter two being rather uncertain from experiment. From the harmonic force constants, harmonic frequencies have been calculated by the method of Wilson and Eliashevich. The equilibrium geometry of HCP has been calculated by the force relaxation method of Pulay.
A Study of the Cubic Phase of Solid Acetylene-d2
Authors: Koski Harri K. 
Published: February 2015

Abstract
The powder pattern of crystalline cubic deuterated acetylene recorded by thermal neutron diffraction technique and the Pa3 crystal structure assigned to the high phase of C2H2 are com-pared. The observations are not in disagreement with the theoretical pattern. Values for the lattice parameters in a narrow temperature range are given.
Irradiation Damage Centers in Magnesiumhypophosphite
Authors: Köksal F. , Yüksel H. 
Published: February 2015

Abstract
An analysis of the electron spin resonance spectra of gamma-irradiated crystals of magnesium-hypophosphite, Mg (H2PO2)2 · 6 H2O, has shown that the main long-lived paramagnetic species produced by gamma-irradiation are HPO2
- and PO3
- ionic radicals. The hyperfine interaction tensor of the phosphorous nucleus has the principal values T|| = 1674, T⊥ = 1221 Mc/s in HPO2
- and T|| = 2490, T⊥ = 1847 Mc/s in PO3
-. In HPO2
- , interaction of the unpaired electron with the proton gives rise to an almost isotropic hyperfine coupling of 233 Mc/s. These results indicate that the orbitals occupied by the unpaired electron in both HPO2
- and PO3
= are sp3 -hybrid σ-orbitals centered on the phosphorous nuclei.