bluuebunny/crossref_metadata_2025_split huggingface dataset:
ESR of Gamma Irradiated KHSO4 Single Crystal
Authors: Köksal F. , Yüksel H. 
Published: February 2015

Abstract
Potassium hydrogen sulphate single crystal has been γ-irradiated at room temperature and its electron spin resonance spectrum recorded by changing the H0 static magnetic field, around an orthogonal axes system. The electron spin resonance spectrum is a single line with a slightly anisotropic g factor. The paramagnetic species has been identified as SO3
- and the principal values of the g tensor has been determined as g1=g2=2.0060, g3 = 2.0045. Direction cosines of the principal
values of the g tensor with respect to the chosen axes have been determined. The spin-orbit contribution to the g-factor has been explained.
A Molecular Dynamics Study of Aqueous Solutions II. Cesium Chloride in H2O
Authors: Vogel P. C. , Heinzinger K. 
Published: February 2015

Abstract
Results of a molecular dynamics study of an aqueous CsCl solution are reported. The system consisted of 216 particles, 200 water molecules, 8 cesium ions and 8 chloride ions and was run over 8000 time steps equivalent of 9 · 10-13 sec. On the basis of radial pair correlation functions, average potential energy of the water molecules and pair interaction energy distribution the static properties of the first hydration shells of the ions are discussed in detail. The self diffusion coefficient for the water molecules is calculated and compared with NMR measurement as well as with molecular dynamics calculations for pure water at elevated temperatures and pressures.
X-Ray Diffraction Study of HCP Metals II. Line Broadening in Polycrystalline Zn and Mg Powder
Authors: Halder N. C. , Johnston E. E. 
Published: February 2015

Abstract
Microstructures of polycrystalline hexagonal close packed (hep) Zn and Mg have been studied by x-ray diffraction line broadening analysis using the integral breadth method, and the Fourier coefficient method. For these two methods, several diffraction peaks were considered to obtain two suitable peak combinations. For the room temperature powder samples, the root mean square (rms) strain was observed to be extremely small. The particle size was anisotropic in both samples with the Zn powder showing more particle size variation than Mg. The average particle size for Zn was about 750 Å, which was over twice the average particle size of 295 Å observed in Mg. The two fault probabilities for Zn turned out to be negligible or zero. Mg, on the other hand, was found to have small, but definite fault probabilities. The deformation fault probability a was 4.5X10-4 and the growth fault prob-ability β was 6.5X10-4 . These results can be compared with the previous work of hep Cd at room temperature, which was found to have no growth fault probability β and a deformation fault prob-ability a amounting to 3X10-3 . This value is higher than that observed in Mg, because for Cd the two fault probabilities were obtained by neglecting the particle size of about 650 Å which actually did exist in the sample.
Analysis of Conducting and Insulating Surfaces by Means of Secondary Ion Mass Spectrometry (SIMS)
Authors: Paz M. De , Macciò C. 
Published: February 2015

Abstract
Using a simple home built apparatus, the surface contamination of various samples maintained at high vacuum conditions is investigated by means of SIMS technique. On a polycrystalline copper surface, at a sample temperature of about 140 K, residual water vapour condensation occurs and ions H+(H2O)n with 1≦n≦11 appear in the positive ion spectrum. On the contrary, on a LiF crystal no water contamination is observed down to 120 K; moreover, on a KI sample, one of the most hygroscopic salts among the alkali halides, only at 130 K an appreciable H2O contamination is detected.
Relative O(1D) Quantum Yields in the near UV Photolysis of Ozone at 298 K
Authors: Moortgat G. K. , Warneck P. 
Published: February 2015

Abstract
Mixtures of O3 with excess N2O were photolysed in the wavelength region 290 - 335 nm using monochromatic light with a band width of 4 nm. The resulting primary product atomic singlet oxygen, O(1D), in reacting with N2O produces in part NO which subsequently reacts with O3 giving rise to a weak infrared chemiluminescence. The emission was monitored with a cooled photomultiplier. The emission intensity is directly proportional to the rate of O(1D) production and it has been utilised to derive the relative O(1D) quantum yield as a function of wavelength between 295 and 320 nm. The data were normalised to a quantum yield of unity of 300 nm and corrections were applied to reduce the error resulting from the spectral band width of photolysing radiation. The O(1D) quantum yields show a temperature dependence. At 298 K the quantum yield is unity up to 305 nm, then declines to zero at 319 nm. At the dissociation limit, taken to occur at γ = 310.3 nm, the quantum yields is 0.57, i. e. considerably below unity. The implications of this result as well as the tail toward longer wavelengths and the temperature dependence are discussed. Ozone absorption cross sections are also reported.
Beweglichkeit und Bildung von Cluster-Ionen im eigenen Gas in He, Ne und Ar unter hohen Drucken
Authors: Heide R. von der 
Published: February 2015

Abstract
A time-of-flight technique is used for the measurement of positive ions mobilities in helium, neon and argon in the 1 - 25 atm pressure range at 25 °C. The reduced mobilities b0 vary with the reduced electric field E/p0 and exhibit different saturation values, which are interpreted in terms of the Langevin theory and connected with the formation of cluster ions:
He+
33 (b0 = 7.4 cm2/Vs), Ne+
13 (3.1), Ne+33 (2.25), Ar+
13 (1.23) and Ar+
33 (0.82).
In Argon also the reduced mobility of Ar+ and Ar+
2 were measured: b0 = 1.56 and 1.84cm2/Vs.
Electron Spin Relaxation of (Diphenyl) in Dimethoxyethane
Authors: Köksal F. , Krüger G. J. 
Published: February 2015

Abstract
The electron relaxation times T1 and T2 have been measured by ESR pulse techniques in solutions of normal and perdeuterated (diphenyl)- in dimethoxyethane at various radical concentrations and temperatures. The results are discussed in terms of different relaxation mechanisms. The most important contribution to spin-lattice relaxation at high concentration is dipolar interaction with other radical electrons modulated by translational diffusion. Spin-spin relaxation has in addition contributions from electron exchange and ion pairing.
Bilokale Feldtheorie der Elementarteilchen
Authors: Vollendorf F. 
Published: February 2015

Abstract
The basic idea of this article is that in a bilocal field theory the Lorentz group can be replaced by the larger group SO (4;4) which contains SO (3;1) as a subgroup. On this basis a system of 24 coupled differential equations is introduced. In the special case of the pion the connection with the local field theory is discussed. It turns out that the application of the local field theory is limited by the reduced Compton wave length λ/2 π of the pion.
The Microwave Spectrum of 2,6-Difluoropyridine
Authors: Stiefvater Otto L. , Lui Stephen , Ladd John A. 
Published: February 2015

Hyperfine splittings of rotational transitions of 2,6-difluoropyridine have been analysed to yield the 14N quadrupole coupling constants. Their values are:
Χaa = 1.82 ± 0.05 MHz, Χbb = - 4.16 ± 0.02 MHz, Χcc = 2.34 ± 0.05 MHz. The electric dipole moment has been determined from Stark effects as fi = 3.82 ± 0.06 D, and satellites in the rotation spectrum have been correlated with the five lowest fundamental vibrations of this molecule.
The dipole moment, the quadrupole data and the structural differences between 2,6-difluoropyridine and pyridine itself can all be accounted for by the change in the electron distribution due to the fluorine substituents.
Zum Mechanismus der 6JHH-Kopplungen in bicyclischen Systemen
Authors: Sterk H. , Wachmann A. 
Published: February 2015

Abstract
Concerning the Mechanism of 9 JHH Couplings in Bicyclic Systems Experimental investigations on bicyclic aromatic systems show the missing of an exocyclic long range coupling. The explanation for this fact can be found by assuming that the through space mechanism owns a greater influence on the amount of the long range coupling constants. On the basis of the different amounts of through space interaction between para-and exocyclic couplings the experimental results can be explained.
Stöße zwischen Thalliumatomen im 62D-Zustand und Molekülen
Authors: Gelbhaar B. , Hanle W. 
Published: February 2015

Energy transfer between the 62D3/2 and 62D5/2 energy levels of thallium, induced by Tl-H2 and Tl-N2 collisions have been investigated. The following cross sections for energy transfer Q(62D3/2 → 62D5/2) and quenching Q(62D3/2) have been determined:
Tl-H2: Q(62D3/2 → 62D5/2) = 87 · 10-16 cm2; Q(62D5/2) = 43 · 10-16 cm2;
Tl-N2: Q(62D3/2 → 62D5/2) = 71 · 10-16 cm2; Q(62D5/2) = 94 · 10-16 cm2.
Präzise Bestimmung von freien Wirkungsquerschnitten für Neutronen / Precision Measurements of Free Cross Sections for Neutrons
Authors: Waschkowski W. , Koester L. 
Published: February 2015

Rotating activation foils with resonance energies of 1.26 eV and 5.19 eV have been applied for exact measurements of neutron cross sections. The detector consisted of a sandwich of two rotating foils and was suitable for determining exactly the neutron flux at the resonance energy and energy changes in the neutron beam. The cross sections of polycrystalline samples showed uncertainties greater than the statistical error. The more accurate measurements on liquid samples yielded the following scattering cross sections of free atoms for neutrons of zero energy:
Lead: σ0(Pb) = (11.261 ±0.006) b,
Bismuth: σ0(Bi) = (9.300±0.003) b, and
Sulfur: σ0(S) = (0.985 ±0.004) b.
These data are of interest for an investigation of the neutron-electron interaction.
Der effektive Spin als Modell zur Beschreibung von ESR- Hyperfeinspektren polykristalliner Systeme / The Effective Spin as a Model to describe ESR-Hyperfine Spectra of poly cry stalline Samples
Authors: Dräger K. 
Published: February 2015

Abstract
Paramagnetic ions with hyperfine interaction generally have an involved ESR-spectrum. For host lattices of cubic symmetry it will be shown that while going from single crystals to powdered systems the true spin quantum number S can be substituted by an effective spin quantum number S' = ½. Using an isotropic spin Hamilton operator the energy-levels and their eigenfunctions as well as the transition probabilities are calculated explitely.
The model is then applied to the ESR-spectrum of manganese-doped polycrystalline CaO. The theoretical spectrum fits the experimental up to 2·10-5 and is in every respect comparable to results of the 3rd order perturbation theory. Above all the model reproduces the true values for the g-factor and the hyperfine coupling constant A as known from single crystal investigations. This is also verified for Mn2+ -ions on cubic sites of MgO and BaO.
Die Struktur epitaktisch aufgedampfter Goldfilme
Authors: Fischer W. , Wißmann P. 
Published: February 2015

Abstract
The texture of 400 Å thick gold films was investigated by plotting the intensities obtained with the help of a texture analyser in a pole figure diagramm. The films had been evaporated under UHV conditions on (111)-, (110)-and (100)-oriented silicon substrates.
The gold films always show a preferred (111)-orientation. This preferred orientation, however, may manifest itself in a (111) fibre texture or a single crystal structure due to different orientation and heating pretreatment of the substrate. Quantitative statements are given on crystal misorienta-tion and azimuthal alignment. The sixfold symmetry of the pole figures can be traced back to the influence of twin stacking faults.
Spektroskopische Messung der radialen Temperaturverteilung in Quecksilber-Hochdrucklampen mit Metallhalogenzusätzen / Spectroscopic Measurement of Radial Temperature Distribution in High-Pressure Mercury Lamps with Metal Halide Additives
Authors: Albrecht H. , Schiff A. 
Published: February 2015

Abstract
The radial temperature distribution in a Hg-high-pressure discharge with metal halogene additives (Sn-, Zn-Iodide) has been measured. Three different spectroscopic methods (Emission-, Absorption-, Bartels-and 2-lines-Method) are compared. The influence of the silica bulb is discussed. High incidence angles for the absorption measurements are realized by use of an elliptic mirror. Emission and absorption measurements in a definite time intervall of the 50 Hz-discharge current was done with signal averaging technique. The arc shows a constriction which is discussed.
NOTIZEN: Energies of Muonic Transitions in Cd and Br and Energies and Intensities of Nuclear Transitions in 78Se and 80Se
Authors: d'Oliveira A. Brandão , Egidy T. von 
Published: February 2015

Abstract
The energies of the muonic 2−1 and 3−2 transitions in Cd and Br have been measured. The c-parameter of the (c, t) Fermi distribution was determined. Energies and inten-sities of nuclear gamma rays in Se are given.
A Simple Variational Method for Quantitative Assessment of "Through-space" and "Through-bond" Interactions
Authors: Schmidt Hartmut , Schweig Armin 
Published: February 2015

Abstract
A simple method is described for separating "through-space" from "through-bond" interactions. The method is applied to 1,4-cyclohexadiene, 2,5-dihydrofuran, 2,5-dihydro-thiophene, and 2,5-dihydropyrrole.
Mittlere Schwingungsamplituden der Tetrahalogeno-Aluminate / Mean Amplitudes of Vibration for the Tetrahalogeno Aluminates
Authors: Baran Enrique J. 
Published: February 2015

Abstract
Mean Amplitudes of Vibration for the Tetrahalogeno Aluminates Mean amplitudes of vibration for the A1X4~ ions (X = F, CI, Br, I) have been calculated from known spectroscopic data, using the L-Matrix Method. The results are briefly discussed, especially in relation with those of isoelectronic species.
Structure of Stark Broadened Hβ Lines at low Electron Densities
Authors: Ramette J. , Drawin H. W. 
Published: February 2015

Abstract
The profile of the hydrogen Hβ line emitted by a hydrogen low-temperature afterglow plasma has been measured at electron densities 1.8·1015 , 1·1015 and 5·1014 cm-3 by means of a 10-channel analyzer system with a spectral resolution of 0.1 Å. All profiles showed weak plasma satellites suddenly appearing at wavelength distances which correspond to the electron plasma frequency and showing “satellite line wings” which slowly smooth out at larger wavelength distances. In the line core-where all quasi-static and ion dynamic theories predict a minimum - appeared an intensity maximum well separated from the closely spaced intensity shoulders. This new feature not yet predicted by line broadening theories and not yet observed by other experimentalists is probably due to low-frequency ion oscillations which couple with the excited atomic system. Such an effect would explain discrepancies between available Stark broadening theories and the mass-dependent structure of line profiles recently observed in other experiments. The effect may possibly be useful for measuring collective low-frequency oscillations in plasmas under very special conditions.
A Molecular Dynamics Study of Aqueous Solutions
Authors: Heinzinger K. , Vogel P. C. 
Published: February 2015

Abstract
Results of a molecular dynamics study of aqueous solutions of LiJ, LiCl, NaCl, CsCl and CsF are reported. The basic periodic box contained 200 water molecules, 8 cations and 8 anions, equivalent to 2.2 molal solutions. Static properties of the first hydration shells of the ions are discussed in detail on the basis of radial pair correlation functions, average potential energies of the water molecules and pair interaction energy distributions. The calculations lead to the conclusion that in the first hydration shells a lone pair orbital of the water molecule is directed towards the cation while a hydrogen atom points towards the anion. In the five alkali halide solutions investigated ion pairing occurs only with CsF. The hydration numbers, when defined as the volume integrals of the ion-water radial pair correlation functions up to the first minimum, increase with increasing ion size and depend on the size of the counterion. The water-water interactions in the solutions show not only features of pure water at elevated temperatures but also of pure water under compresion. The agreement between calculated and measured self diffusion coefficients is still insufficient.
Depolarization of NaD2 Fluorescence under Pulsed Laser Excitation
Authors: Kroop V. , Behmenburg W. 
Published: February 2015

Abstract
The intensity and polarization state of the NaD2-fluorescence (3 2P3/2→3 2S1/2 , λ 5890 Å) from a cell containing pure Na vapor, selectively excited by a flash lamp pumped dye laser was investigated. Measurements were performed both for excitation with π-and σ-light of spectral density ranging between 10-23 and 10-17 Ws2 cm-3 and with Na number densities between 2.8 X109 and 4.0 X 1010 cm-3. The results are interpreted in terms of population of the 2P3/2 state and of hyperfine and Zeeman pumping of the 2S1/2 substates. The values for the degree of linear polarization measured at the smallest excitation densities and Na pressures agree well with theoretical values.
Chemical Oscillations by Substrate Inhibition
Authors: Seelig Friedrich Franz 
Published: February 2015

Abstract
The general reaction X+Y→P+Q, catalyzed by a metal M via M+X⇄MX and MX+Y→M+P+Q (or, in another subcase, MX+Y⇄MXY→M+P+Q) renders a chemical oscillator, if in an open system X and Y are supplied from appropriate sources by influxes j1 and j2, respectively, if X shows substrate inhibition by subtracting active catalyst by forming an inert complex MX2, and if at least X is limited by an additional first order side reaction. Introduction of dimensionless variables and parameters and assumption of a partial steady state for the catalyst compounds, the sum of wbich is constant, leads to 5 (or 6) parameters, 3 of which can be easily adjusted in a wide range. It is shown that for any given values of the 2 (or 3) fixed parameters the adjustable ones can in principle be chosen in such a way that the conditions for oscillation are met. This type of oscillator is thus a parametrically universal one. By appropriate choice of the adjustable parameters the yield of products can be conducted in bursts instead of a continuous flow. Another possibility is an excitable system that fires only on triggering. Proposals toward chemical realization are discussed especially with respect to transition metal complexes.
Equation of State and Thermodynamic Properties of Molten Potassium Chloride to 1320 K and 6 kbar
Authors: Goldmann G. , Tödheide K. 
Published: February 2015

Abstract
From the Tait equation an equation of state containing five adjustable parameters was developed which fits experimental density data of molten potassium chloride to 1320 K and 6 kbar with a standard deviation of 0.04%. The thermal expansion coefficient, isothermal compressibility, internal pressure, and molar heat capacities at constant pressure and constant volume were calculated as functions of pressure and temperature from the equation of state and were compared with computer simulation results. A method for an estimate of high-pressure PVT data for molten salts is suggested which yields results superior to the best computed data presently available.
Electronic Overlap Population as Reactivity Measure IV. Bond Cleavage and Bond Formation Processes
Authors: Sharafi-Ozeri S. , Muszkat L. , Muszkat K. A. 
Published: February 2015

Abstract
Electronic overlap population is explored as a reactivity measure for several bond cleavage and bond formation processes. The reactions considered include: I. decarboxylation of carboxylic acids and of their anions; II. carbon-hydrogen bond cleavage in γ-radiolysis of glutaric, methyl-malonic and 3-hexendioic acids; and, III. hydrogen atom addition to butadiene and to sorbic acid.
Radial Poiseuille Flow of a Homeotropic Nematic LC Layer
Authors: Hiltrop Karl , Fischer Fred 
Published: February 2015

Abstract
A two-dimensional Poiseuille flow in a radial direction allows to study simultaneously a whole range of flow rates. Three different deformation modes of the director field have been observed, the 'bow' mode, the 'screw' mode, and the 'peak' mode. Above a critical flow rate the bow mode transforms into the screw mode. Right and left screw mode can be produced side by side. The peak mode reached by temporary high flow rates is metastable at low flow rates. Quantitative results are reported and discussed.
By reversing the flow direction in the screw mode region the left screw mode is transformed into the right screw mode and vice versa.
By reversing the flow direction in the peak mode region special tube-like deformation structures are obtained. Each open tube has a point disclination at either end. Both are of opposite strength ± 1.
The T-t Jahn-Teller System: Solution of the Fundamental Combinatorial Problem and its Application to Moments and Zero Phonon Line
Authors: Sigmund E. 
Published: February 2015

Abstract
The solution of the T-t fundamental combinatorial problem is given in a purely analytic form as a sum over binomials. This simplifies other calculations considerably. For an illustration the moments of the optical absorption line shape in the strong coupling limit are derived in a closed form. Furtheron, the optical zero phonon line is calculated. An application to a T - t phase transition chain is indicated.
Stable and Metastable Phases in the Systems AgI-Ag2XO4 (X=Cr, Mo, W)
Authors: Magistris Aldo , Chiodelli Gaetano , Campari Giuseppina Viganò 
Published: February 2015

Abstract
DTA and powder x-ray diffraction measurements allowed to draw the phase diagrams of the systems AgI-Ag2XO4 (X = Cr, Mo, W).
A more detailed investigation was devoted to the composition range around XAgI = 0.8, where in preliminary tests it was observed that the room temperature ionic conductivity strongly depends on the thermal treatment of the sample.
By quenching mixtures at XAgI = 0.8, glass-like phases with high conductivity were obtained; in the systems AgI-Ag2CrO4 and AgI-Ag2MO4 the subsequent crystallization gave rise to non con-ducting phases, whereas the occurrence of the highly conducting compound 4AgI·Ag2WO4 was recognized in the third system investigated.
Photochemisches Verhalten und spektroskopische Eigenschaften von Anilino-naphthalinen
Authors: Fratev F. , Polansky O.E. , Zander M. 
Published: February 2015

Abstract
From the fluorescence and phosphorescence spectra of several aromatic amines it is concluded that the conjugation between nitrogen and aryl groups in the excited state is restricted. With this result a sterical explanation for the lack of the expected photochemical carbazole ring closure of 1-and 2-anilino naphthalene is given.
Fokker-Planck-Equation Approach to Flow Alignment in Liquid Crystals
Authors: Hess Siegfried 
Published: February 2015

Abstract
A nonlinear inhomogeneous relaxation equation for the alignment tensor is derived from a Fokker-Planck-equation for the orientational distribution function where torques exerted by a molecular field and by the gradient of the flow velocity are taken into account. Phenomenological coefficients characterizing the flow alignment in the isotropic and in the nematic phases are related to molecular parameters.
A Molecular Dynamics Study of Aqueous Solutions V. Angular Distribution of the Water Dipoles in the Hydration Shells of Various Alkali-and Halide Ions
Authors: Heinzinger K. 
Published: February 2015

Abstract
The angular distributions of the water dipoles have been calculated from molecular dynamics runs for the first hydration shells of various ions in 2.2 molal LiJ, LiCl, NaCl, CsCl and CsF solutions and in a 0.55 molal NaCl solution. It is shown how the distributions depend on the size of the shell taken around each ion. The results give no indication for the existence of desoriented water molecules in the immediate neighbourhood of the ions.