bluuebunny/crossref_metadata_2025 huggingface dataset:
The Mössbauer-Effect o f the 104 keV Transition in 180W
Authors: Zioutas K. , Wolbeck B.
Published: February 2015

The Mössbauer effect of the 2 + (104 keV)0+ transition in 180W has been observed. The source was 180Ta which was produced by irradiation of a foil of natural tantalum by fast neutrons: 181Ta(n, 2n) 180Ta. The width of the resonance absorption line was (3 .1 ± 0.8) mm/sec which corresponds to the linewidth derived from lifetime measurements.
Bestimmung einer empirischen Formel zur Abschätzung der im ultravioletten Spektralbereich liegenden VK-Absorptionsbande
Authors: Podszus B.
Published: February 2015

An empirical relation has been found between the ionic radii of the crystal-lattices and the ultraviolet absorption wavelengths of the VK-centers. The relation is valid for VK - centers formed in alkali halide crystals with NaCl structure as well as for ammonium halide crystals with CsCl structure.
The Spectrum of Steady State Turbulent Convection
Authors: Winterberg F.
Published: February 2015

Based on Heisenberg's statistical theory of turbulence, a model for steady state turbulent convection is herein proposed, and on the basis of this model, equations for the energy spectrum for steady state turbulent convection are derived. The spectrum is obtained from the solution of a nonlinear integral equation. After the integral equation is brought into a universally valid nondimensional form, it is transformed into a nonlinear first order differential equation to be solved numerically, with the Rayleigh number appearing as the only parameter. The energy spectrum has a substantial deviation from the Kolmogoroff law, as a result of the buoyancy force acting on the rising and falling eddies. The presented theory may be applicable to convection in planetary and stellar atmospheres wherein the radiative heat transport is small.
Application of Homonuclear INDOR to a Study of the PMR Spectrum of 15N-pyrrole
Authors: Rahkamaa Erkki
Published: February 2015

Homonuclear INDOR method has been applied to investigate the assignment of some lines of the PMR spectrum of 15N-pyrrole to the transitions in the energy level diagram of the AA'BB'C spin system. This study, based on the characters of some connected transitions and the corresponding line positions, shows that the couplings 1JNH , 2JNH and 3JNH carry the same signs, which is in accordance with a result obtained by the tickling method.
The Isotopic Abundance of Neon, Argon and Krypton
Authors: Melton Charles E. , Massey W . , Abels B . N.
Published: February 2015

Two research mass spectrometers combined with careful experimental techniques have been used to redetermine the iotopic abundances of atmospheric neon, argon and krypton. No instrumental correction factor was necessary to duplicate the known results for neon. The new isotopic abundance of argon is essentially identical to that previously obtained by Nier. On the other hand, some differences in the present and previous values were noted in the isotopic abundance of krypton. The new values for the nuclides of krypton are

78Kr=0.355±0.001, 83Kr=11.536±0.009 ,

80Kr=2.256±0.007 , 84Kr = 56.982 ± 0.01 ,

82Kr=11.553±0.009 , 86Kr=17.318±0.009 .

The atomic weight calculated on the basis of these new values and 12C= 12.0000 is 83.8005 ± 0.001 amu.
Experimentelle Untersuchungen der Rückstreuung von U235-Spaltteilchen an Goldschichten
Authors: Albrecht J. , Ewald H.
Published: February 2015

U 235 fission products of known mass number ( = 135) and energy ( = 74.35 MeV) are scattered from polycristalline gold layers of about 1000 Å and 0.4 mm thickness at different angles of incidence (5°, 10°, 15° and 20° towards the surface) The reflected particles are traced by glass plates and Si surface barrier detectors. From the numbers, the positions and the diameters of the etched traces in the glass plates the percentages of the backscattering, the angular distributions, and the energies of the reflected particles are obtained
Elektrische Transportgrößen von n- und p-ZnSb
Authors: Müller H.-G. , Schneider G.
Published: February 2015

Nachdem nun die Herstellung von n-ZnSb gelungen ist, wird hier erstmals über das Verhalten einer größeren Anzahl ZnSb-Proben vom n-Typ berichtet. Die Herstellung der Proben mit Indium- Dotierung wird beschrieben, das instabile Verhalten bei Zimmertemperatur dargestellt. Die Temperaturabhängigkeit der elektrischen Transportgrößen (elektrische Leitfähigkeit, Hall-Effekt, Thermokraft, transversaler Nernst-Ettingshausen-Effekt) zeigt im Bereich von 80 °K bis Zimmertemperatur ein ähnliches eigenartiges Verhalten wie es für CdSb und ZnSb-CdSb-Mischkristalle gefunden wurde; bei Zimmertemperatur n-leitende Proben zeigen bei tiefen Temperaturen einen positiven Hall-Koeffizienten und eine positive Thermokraft. Eine erste Abschätzung für die Elektronenbeweglichkeit von ZnSb kann gegeben werden; für tiefe Temperaturen ergeben sich für diese Proben kleine Beweglichkeiten und niedrige Konzentrationen der Defektelektronen. Für im ganzen vorliegenden Temperaturgebiet p-leitende undotierte und dotierte Proben werden entsprechende Ergebnisse für die Transportgrößen, die Beweglichkeiten, Ladungsträgerkonzentrationen und effektiven Massen mitgeteilt
Diffuse Reflectance Spectrum of Some Pr3+ Complexes
Authors: Tandon S. P. , Govil R. C.
Published: February 2015

Diffuse reflectance spectra of eight Pr3+ complexes in the visible region have been recorded for the first time. From them, values of Slater-Condon (F2, F4, F6), Racah (E1, E2, E3) interelectronic repulsion, and Lande (ζ4f) parameters have been computed. The decrease in F2 values of the complexes as compared to the free ion is greatest among all the parameters. The bonding parameter b1
2 has been computed from the observed nephelauxetic ratio. The relative variation of covalent bonding in the complexes has been discussed
Quantenchemische Untersuchungen an Acetylen, Tetrachloroaluminat(III)-ion und Lithiumtetrachloroaluminat(III)
Authors: Drossbach P. , Hoff H.
Published: February 2015

Die Moleküle bzw. Ionen C2H2, AlCl4
- und LiAlCl4 wurden unter Berücksichtigung aller ihrer Elektronen nach dem SCF-MO-LC-LCGO-Verfahren berechnet. Orbitalenergien, Besetzungsarten Orbitalschwerpunkte und Dipolmomente wurden mitgeteilt. Die Röntgen-Terme werden im Vergleich zu den freien Atomen durch die chemische Bindung in den Molekülen nicht nur abgesenkt, sondern können durch die Elektronenwechselwirkung auch angehoben werden. Die Entladung eines Ions bei gleichzeitigem Übergang mehrerer Elektronen wird diskutiert,
Recovery of the NMR Signal of Plastically Deformed Alkalijodide Single Crystals
Authors: Kanert  , Kotzur D.
Published: February 2015

The annealing process of plastically deformed RbJ-and KJ-single crystals has been studied by means of NMR wide line and spin echo measurements on J127 . The mean lattice strain produced by the deformation is correlated with a mean quadrupole perturbation affecting the NMR signal. Resulting from second order quadrupole effects, the wide line measurements lead to a recovery temperature, which is much lower than the "real" recovery temperature given by the spin echo method. Nevertheless the evaluation of both types of measurements results in the same effective activation energy depending on the degree of deformation. The obtained values are probably caused by the migration of positive ion vacancies.
Beeinflussung des spezifischen Widerstandes und der Thermokraft aufgedampfter Nickelfilme durch Kohlenmonoxid-und Wasserstoff adsorption bei 273 °K
Authors: Welder G. , Reichenberger H. , Wenzel H.
Published: February 2015

An unter Ultrahochvakuumbedingungen aufgedampften Nickelfilmen werden bei 273 °K die durch die Kohlenmonoxid-und Wasserstoffadsorption hervorgerufenen Änderungen des spezifischen Widerstandes und der Thermokraft in Abhängigkeit von der Dicke der Metallfilme und der Belegung untersucht.

Es wird gezeigt, daß die beobachteten Effekte von der Größenordnung sind, wie sie auch bei einigen binären Legierungen des Nickels gefunden werden und daß sich ihre Abhängigkeit von der Schichtdicke qualitativ mit einem Ansatz beschreiben läßt, bei dem die adsorbierten Teilchen als punktförmige Streuzentren betrachtet werden. Abweichungen bei sehr dünnen Filmen und die Größe der Thermokraftänderung deuten auf zusätzliche Einflüsse hin.
Anisotropie galvanomagnetischer und thermomagnetischer Effekte in verschieden dotiertem Bi88Sb12
Authors: Fay B. , Schneider G.
Published: February 2015

Verschieden dotierte Bi88Sb12-Proben wurden durch Zonenschmelzen hergestellt. Neben dem Donator Te interessierten dabei besonders verschiedene Akzeptordotierungen; die Akzeptorwirkung der aus verschiedenen Gruppen stammenden Elemente Sn, Ga, Cd und Ag nimmt entsprechend der angegebenen Reihenfolge ab. Dabei wurde der Einfluß auf die Temperaturabhängigkeit der elektrischen Transportgrößen, wie den elektrischen Widerstand und die Thermokraft, untersucht. Systematische Untersuchungen des Einflusses der Dotierungen auf die Anisotropie der transversalen magnetischen Widerstandsänderung wurden durchgeführt, wobei weiter die Abhängigkeit von der Größe des Magnetfeldes und der Temperatur studiert wurde. Die auftretenden Änderungen der Anisotropien werden diskutiert. Ganz entsprechende Untersuchungen über die Anisotropie der Thermokraft im transversalen Magnetfeld schließen sich an.
Electrical Transport Phenomena in Molten Salts
Authors: Timmermann E. O. , Richter J.
Published: February 2015

The equivalent conductivity of molten salts containing more than two ion constituents will be discussed using the equivalent fractions (Äquivalentanteile). The ionic conductivities of the ion constituents follow from this equivalent conductivity and the transport numbers. The electrical transport phenomena are referred to the idealized ionic melt which is defined by the limiting values of the ionic conductivities of the ion constituents in the pure components. The equations are calculated for the system KNO3+AgNO3.

Es wird die Äquavilentleitfähigkeit bei Salzschmelzen mit mehr als zwei ionischen Bestandteilen mit Hilfe von Äquivalentanteilen diskutiert. Aus dieser Äquivalentleitfähigkeit und den Überführungszahlen ergeben sich mit den Äquivalentanteilen die Ionenleitfähigkeiten der ionischen Bestandteile. Die elektrischen Transportphänomene werden auf eine idealisierte Salzschmelze normiert, die mit den Grenzwerten der Ionenleitfähigkeiten der ionischen Bestandteile in den reinen Komponenten definiert wird. Die Gleichungen werden berechnet für das System KNO3+AgNO3.
Functional Quantum Theory of Scattering Processes. III
Authors: Stumpf H. , Engeser W. , Illig K.
Published: February 2015

Dynamics of quantum field theory can be formulated by functional equations. To develop a complete functional quantum theory one has to describe the physical information by functional operations only. The most important physical information of elementary particle physics is the matrix. In this paper the functional S-matrix is constructed for nonrelativistic spin 1/2 fermions, as in this system a rigorous construction of operator representations is possible. The method of S-matrix derivation used in I and II is improved and the exact perturbation solution for the scattering functionals is given.
Can Quantum Theory be presented as a Classical Ensemble Theory?
Authors: Ochs Wilhelm
Published: February 2015

We examine the possibility of reformulating quantum theory (QT) as a deterministic ensemble theory which (a) interprets observables as objective properties of physical systems and (b) coincides with QT in all quantitative statements. As will be demonstrated, such an Ensemble-Quantum-Theory (EQT) can only be constructed if (1) one accepts a modified observable-concept, and (2) as long as the theory of measurement is left out of account. A correct treatment of the measuring process is impossible within such an EQT. Consequently, there exist no Hidden-Variable Theories with the properties (a) and (b).
Notizen: The Inversion of the Tunneling Conductance Formula
Authors: Engler Hans
Published: February 2015

Inversion formulas are given for determining the density of states by tunneling conductance measurements.
Über die Bildung von Molekülkomplexen bei der Feldionisation organischer Moleküle
Authors: Beckey H. D. , Migahed M. D.
Published: February 2015

Hetero-dimer ions are observed in the field ionization mass spectra of aniline-nitrobenzene mixtures, and also in mixtures of some other organic substances which yield charge-transfer complexes in solutions. It is shown that the structure of the hetero-dimer ions is different from the sandwich structure of the corresponding CT-complexes in solutions. Arguments are given for assuming hydrogen bonds between the components of the complexes, with an additional weak CT-bond
On the Motion of a Charged Particle in an Axially Symmetric Magnetic Field
Authors: Bharadwaj V. L.
Published: February 2015

The object of this note is to study the motion of a charged particle entering the magnetic field due to a steady current inside a plasma column. Even if the particles of the plasmas stream mutually interact, their distribution across the stream can be such that the interaction forces are balanced by the transverse pressure gradient in the plasma 1. It is shown here that the test charge entering the plasma stream remains bounded to the stream between two coaxial cylindrical surfaces and further that under suitable conditions it may remain trapped inside a cylindrical box. FISSER and KIPPENHAHN 2 have discussed the general problem of the motion of a charged particle in an axially symmetric magnetic field in configuration space. The following is a particular case of that problem. HERTWECK 3 has investigated the motion of a test charge in the magnetic field due to a line current. His results are applicable here if the test charge remains outside the plasma stream
Beiträge zum Stark-Effekt der Moleküle 205Tl19F und 39K19F / Contributions to the Stark-Effect of the Molecules 205Tl19F and 39K19F
Authors: Dijkerman H. , Flegel W. , Gräff G. , Mönter B.
Published: February 2015

The dominant contribution to the Stark-effect energy of polar 1Σ diatomic molecules can be calculated from the model of the rigid rotator. Additional terms arise from the anharmonicity of vibration, the centrifugal distortion, the vibration-rotation interaction and the electronic polarizability.

These contributions to the Stark-effect have been investigated for the molecules 205TlF and 39KF with a molecular beam electric resonance apparatus suitable to detect rotational transitions. Measure-ments have been performed at values of electrical field corresponding a) to a minimum in the frequency for the transition (J, mJ) = (1, 0) → (2,0) for vibrational states v = 0, 1, 2 and b) cor-responding to the electrical field where the transitions (J, mJ) = (1, 0) (0, 0) and (1, 0) → (2, 0) for v = 0 occur at the same frequency.

Interpretation of our data requires more precise values of the Dunham coefficients than have been published to date. These coefficients therefore have been recalculated from rotational transitions measured at zero electrical field.
Thermodynamic Properties of Alkali Nitrate—Silver Nitrate Melts
Authors: Richter J. , Sehm S.
Published: February 2015

EMF measurements were performed on a chemical cell containing a silver and a nitrate electrode. The systems NaNO3 + AgNO3 , LiNO3 + AgNO3, and pure AgNO3 were investigated in a temperature range of 240 °C to 310 °C and in the total concentration range permitted by the phase diagram. We found a linear dependence of the EMF on temperature. Six constants, characteristic for the investigated molten salts depending neither on composition nor on temperature, were determined by the analytical construction of the activity coefficients. Together with the analytically constructed excess molar Gibbs function, the excess molar entropy was calculated from calorimetric data in the literature.
Die kinetischen Konstanten des Triplett-Zustandes von Fluoren-Molekülen / The Cinetic Constants of the Triplet Stale of Fluorene Molecules
Authors: Sixl H. , Wolf H.
Published: February 2015

The metastable triplet state T1 of fluorene molecules in a fluorene crystal, disturbed by the presence of dibenzothiophene (“X-traps”) was investigated at 1.6 and 4.2 °K. From ESR measurements a model for the fluoren X-traps is derived. The X-trap molecule is misoriented by an angle of 2,5° in the fluorene crystal.

The rate constants for population (s), radiative decay (kD) and total decay (k) of the three magnetic sublevels of T1 were determined by analysis of phosphorescence intensity and decay time in high magnetic field and by optically detected ESR. We find (with z = axis perpendicular to the molecule, x = long axis):

The average spin lattice relaxation rate constant is w = (0.8 ± 0.2) sec- 1 .
Notizen: Zur Beteiligung des Triplettzustandes im Kristall an der sensibilisierten Erzeugung von Defektelektronen in aromatischen Kohlenwasserstoffen
Authors: Willig F.
Published: February 2015

The steady-state spatial distribution has been calculated for triplet excitons generated at the surface of an anthracene crystal. The dependence on the light intensity has been discussed for a hole generation and delayed fluorescence, due to the triplet excitons.
Notizen: Reactivation of Mechanical Aftereffect of Iron Single Crystals by Discontinuous Change of External Magnetic Field
Authors: Markert H.
Published: February 2015

First experiments on iron single crystals are outlined demonstrating that the mechanical aftereffect can be reactivated remarkably by discontinuous changes in superimposed magnetic fields. As magnetostrictive effects not only are very much smaller but can also be separated experimentally, it appears to be necessary to interpret the observed phenomena by interactions between domain walls and dislocations having mutual orientations suitable to enable reactivation of disclocation glide caused by the repulsive interaction forces of the domain walls.
Diffraction Patterns Obtained by Scanning Electron Microscope
Authors: Fujimoto F , Komaki K , Takagi S , Koike H
Published: February 2015

Kossel-Möllenstedt and Kikuchi patterns are obtained by transmission scanning electron microscopy and compared with those obtained by the convergent beam technique from the same portion of the specimen. The identity of corresponding patterns obtained by both techniques shows the validity of the reciprocal theorem in electron diffraction for both elastic and inelastic scattering. The variations of Kossel-Möllenstedt patterns with the conditions of the incident beam and the position of the detector are also shown.
Der Einfluß starker elektrischer Felder auf Intensität und Lage der Bragg-Reflexe / The Influence of Strong Electrical Fields on Intensities and Positions of Bragg-Reflections
Authors: Chrpa E , Ihringer H , Jagodzinski H , Kneifel A
Published: February 2015

Die Volumenpolarisation, die man durch die Einwirkung von elektrischen Feldern mit einer Feldstärke bis zu 106 V/cm berechnet, sind so klein, daß man nur geringfügige Polarisationen und Verschiebungen der Atome erhält. Sie sind aber mit modernen Meßmethoden der Rüntgen-Streuung an Einkristallen nachweisbar. Im Falle des LiF wird gezeigt, daß die gemessene relative Atom-verschiebung ca. 4·10-3 Å beträgt und etwa eine Größenordnung höher liegt als der theoretisch berechnete Wert.

Wesentlich stärkere Abweichungen werden an Quarzkristallen beobachtet. Hier gelingt die Deutung der beobachteten Intensitätsänderungen über Atomverschiebungen nicht; wahrscheinlich liegt daher ein Zusammenwirken von Atomverschiebungen und Extinktionsminderung durch elektrisch geladene Gitterstörungen vor. Die Verwendung des Effekts für die Strukturanalyse wird diskutiert.
Untersuchungen an stromstarken Kapillarentladungen. Teil I. Vorbereitende Untersuchungen / Investigations on High Current Capillary-Discharges. Part I: Preliminary Investigations
Authors: Kusch Hans Jürgen , Schreiber Harald
Published: February 2015

A pulsed discharge through plastic capillaries is investigated using spectroscopic and cinematographic techniques. In the wavelength region 2600 - 5600 Å the emission was nearly that of a black body of 30 000 °K lasting for nearly 150 μsec; therefore the light source can be used as a suitable radiation-standard in μsec-spectroscopy. The optical thickness is measured and compared with calculations of continuum-intensity. Estimates of pressure and electron density lead to values of 150 atm max. and 2·1019 cm-3 respectively. Also the plasma jet protruding from the capillary is investigated.
Diffusion of He, Ne, and Ar in Vitreous and Partially Devitrified Germani um Dioxide
Authors: Brandt W.W. , Rauch B. , Wagner J.
Published: February 2015

The diffusion coefficients of He, Ne, and Ar in various samples of GeO2 and approximate values for the corresponding solubility coefficients were obtained from nonisothermal and isothermal desorption experiments. The data show trends similar to those obtained on fused SiO2 , and are interpreted by assuming that the glasses contain many interstices of different critical dimensions and a variety of diffusion paths corresponding to a range of activation energies. Some annealed and partially devitrified samples were studied and the activation energies of diffusion were found to be relatively high. In a few cases, the measurements were extended into and above the glass transition range (∼570°) ; the resulting activation energy and the preexponential factor of the Arrhenius equation for the diffusion coefficient were markedly increased, indicating that the diffusion mechanism is probably drastically changed.
Spin Effects in the Two-particle Equati on of the Exciton
Authors: Zwanzger J , Muschik W , Haug A
Published: February 2015

Starting from a two-particle equation of the exciton which includes beside the Coulomb inter-action a spin-dependent exchange term the influence of the electron and hole spin on the exciton spectrum is studied by taking into account spin-orbit and spin-spin interaction. A rough estimate of the resulting splitting is given. In a second part the effect of the spin-dependent exchange term in a magnetic field is investigated. The result is that the usual spin splitting for s-states can not be observed
Einfluß von Chlorsubstitution auf die El ektronenspektren von Biphenyl
Authors: Dreeskamp H. , Hutzinger O. , Zander M.
Published: February 2015

Absorption spectra in liquid solution, fluorescence and phosphorescence spectra, phosphores-cence quantum yields, phosphorescence to fluorescence quantum yield ratios, and phosphorescence decay times of 9 chloro substituted biphenyls dissolved in low temperature EPA glass were in-vestigated. The emission spectra of sterically unhindered systems are structured and significantly Stokes-shifted. Ortho substitution shifts the conjugation band in absorption as well as the un-structured fluorescence and phosphorescence bands to shorter wave lengths presumably by pre-venting the system from attaining a planar excited state. Chloro substitution which increases the rate constant of phosphorescence in the order meta < para < ortho, is nearly additive for multiple substituted systems and is correlated to the MO coefficients at the chloro substituted position in the absence of steric hindrance
Luminescence of Diatomic Molecules II. Energy Dependence of Collisional Deactivation Cross Sections
Authors: Comes F. J. , Speier F
Published: February 2015

Photoionization has been used to produce ions of N2, O2. and CO in definite excited states. Deactivating collisions of these ions with molecular gases were described in paper I, where the cross sections of ions with thermal velocity are given for various electronic and vibrational states. By application of an electric field the charged particles are accelerated yielding information on the influence of the kinetic energy of the collision partners on these deactivating collisions. The cross section is found to follow an exponential law σ ~ E-α, with a varying between 0.34 and 0 41 for the different excited stales of the molecular ions. The observations were carried out for a range of kinetic energies from the thermal energy up to 6 eV maximum. This simple exponential law is followed for kinetic energies up to at least 2 eV. At higher energies slight deviations were found to occur
Drei Verfahren zur Messung der Änderung der Austrittsarbeit mit Hilfe der Oberflächenionisation
Authors: Müller R , Walcher W , Wassmuth H.-W
Published: February 2015

Three methods for the measurement of the change ΔΦ of the work function Φ of a metal surface due to the presence of adsorbed particles (e. g. oxygen) have been developed utilizing the surface ionization of a beam of metal atoms (e. g. In, Sr) as a probe. The experiments have been performed with a mass spectrometer at ultrahigh vacuum.

In the first method the temperature dependency of the ion emission current is used for the determination of the work function Φ considering certain limiting conditions. The two other methods which may be applied simultaneously with the first one, involve a direct measurement of ΔΦ by compensating the change of the contact potential by an external voltage: In the second method the contact potential between the ionizing surface and a surrounding reference electrode is used to control the ion optical conditions for the ion emission, whereas in the third method the change in the kinetic energy of the ions caused by a change of the contact potential between the ionizing surface and the entrance slit of the mass spectrometer is used as a measure of ΔΦ
Simplified expressions for the calculation of the contribution of the heavy components to the transport coefficients of partially ionized gases
Authors: Capitelli M.
Published: February 2015

Simplified expressions for the calculation of the contribution of the heavy components to the viscosity and to the translational thermal conductivity have been tested for pure and mixed plasmas
Isotopieeffekte in den Hydratstrukturen von festem und gelöstem Kupfersulfat / Isotope effects in the hydrated structure of solid and aqueous copper sulphate
Authors: Maiwald B , Heinzinger K
Published: February 2015

The fractionation of the oxygen isotopes of the water molecules in CuS04-5 H20 and in aqueous solutions of copper sulphate has been measured at 25 °C. In the total crystal water (G) three kinds of water can be distinguished by their binding: 1) The bisector of the two lone pairs directed to­wards the copper ion (Kj), 2) One of the lone pairs directed towards the copper ion (K2), 3) The two lone pairs directed towards two hydrogen atoms of water molecules coordinated with the cop­per ion (L). The water molecules in the copper sulphate solution are considered either hydration water (HW) or bulk water (FW). Defining a.\-B= (180/160)a/(180/180)b the following results have been obtained:

There remains some doubt if the values attributed to ctKi-G and aK2-G have to be interchanged. The elementary cell of CuS04*5 H20 consists of two molecules. Four molecules of Kj-water are coordinated with one copper ion and four molecules of K2-water are coordinated with the second copper ion. The remaining two water molecules are of L-type. It is concluded from the results that on dehydration at temperatures below 50 °C first one copper ion loses it’s water and then the other. There is some doubt as to which group breaks up first. In addition, the results show that the L-type water becomes quantitatively the water of the monohydrate in agreement with the conclusions drawn from the results of the fractionation of the hydrogen isotopes in CuS04-5 H20. It is de­monstrated that, by considering only the overall fractionation of the oxygen or hydrogen isotopes between total crystal water and the saturated solution, wrong conclusions about the crystallization process could be drawn. In the case of CuCl2 solutions, it has been shown that the separation factor aHW-FW is sensi­tive towards changes in the structure of the solution.
Normal Coordinate Analysis of Nitrogentrichloride
Authors: Rai S. N . , Rai Badri , Nair K. P. R . , Thakur S. N.
Published: February 2015

The intramolecular force fields of nitrogen trichloride have been determined using the recent experimental data on the vibrational frequencies. Three different methods have been used for the evaluation of force constants. The results ob-tained are quite consistent
A Liquid Self-Diffusion Model
Authors: Lodding A
Published: February 2015

The postulate that a liquid possesses characteristic frequen­cy and enegy of vibration, and that all other energy goes to “free” diffusion, leads to the relation

where Tm is the melting point, M the atomic mass, V the atom­ic volume and L the heat of fusion. A is a constant obtainable from the Lindemann relation, 0.36 for the alkali metals, 0.30 for noble metals. This relation is in very good agreement with experimental self-diffusion data of liquid metals
Dreidimensional abbildende Elektronenmikroskope I. Prinzip der Geräte / Threedimensionally Imaging Electron Microscopes
Authors: Hoppe W.
Published: February 2015

Threedimensionally Imaging Electron Microscopes The principles of new electron optical imaging systems will be described which make possible the threedimensional image construction of a small object. Data of threedimensional Fourier space are collected by the registration of several images using primary beams with different tilting angles. The simplest device of such a type - a magnetic fly's eye system - will lead to spherical aberrrations larger than about 20 mm. It will be shown, that there is a good chance to correct “ring zone segment”-systems to reach atomic resolution with or without image-reconstruction-calculations. Not only microscopes with conventional bright field and dark field imaging but also transmission scanning microscopes can be constructed usind these principles.
Das ν1/ν3-Frequenzen-Verhältnis bei tetraedrischen Oxoanionen der Hauptgruppen- elemente und die Schwingungseigenschaften von Xenon-Tetroxid / The ν1/ν3 Frequency Ratio in Tetrahedral Oxoanions of The Main Group Elements and the Vibrational Properties of Xenon-Tetroxid
Authors: Baran Enrique J.
Published: February 2015

In an earlier work we have theoretically derived and explained certain rules relating the ν1/v3 frequency ratio of tetrahedral oxoanions of the transition metals with some basic properties of the anions. It is now demonstrated that these rules are also valid for oxoanions of the main group elements of the periodic system. Applying these and other relations it was possible to predict the value of the symmetric stretching frequency ν1(A1) of xenon tetroxide. Some vibrational properties of XeO4 (force constants, mean amplitudes of vibration, the Coriolis coupling constant and the bond order) are also calculated and compared with those of related species.
Kinetics of the Solid State Reaction between MoO3 and SrCO3
Authors: Flor G. , Massarotti V. , Riccardi R.
Published: February 2015

The solid state reaction MoO3 + SrCO3 → SrMoO4+ CO2 has been studied on mixtures of powdered reagents.

Thermogravimetric measurements in the temperature range 412° -498 °C have been made on different mixtures and under different atmospheres. Moreover, optical observations and conductometric measurements have been carried out.

The results show that the reaction is governed by a diffusion mechanism with an apparent activation energy of (60 ± 1) kcal/mole and that the main diffusing species is the Mo6+ ion.
Diffusion und Korrelation in goldreichen Gold—Zinn-Mischkristallen / Diffusion and Correlation in Gold-Rich Gold—Tin Solid Solutions
Authors: Herzig Chr. , Heumann Th.
Published: February 2015

The diffusion of Sn-113 and Au-195 in pure gold and dilute tin -gold alloys has been measured at different temperatures and tin concentrations in coarse-grained specimens. In addition the dependence on concentration of the chemical diffusion coefficient and the diffusion of tin in gold at very low impurity concentrations has been determined using the electron microprobe. It was found, that the self-diffusion coefficient of tin as well as that of gold increased strongly with in-creasing impurity content. The thermodynamic factor is equal to one up to ca. 0.5 at.-% tin. For the correlation factor of the diffusion of tin in gold, calculated by the relation of Lidiard, an essentially temperature independent value is obtained. A comparison of the experimental results with the model of Le Claire concerning the impurity diffusion in metals shows, that this model seems to require a too-large temperature dependence of the correlation factor
Untersuchungen zum Kristallisationsprozeß in Selenpreßkörpern
Authors: Kispéter J , Gombay L , Lang J
Published: February 2015

The crystallization of compressed selenium was investigated by measurements of the spectral dependence of the photocurrent and of the thermally stimulated current (TSC). A comparison of these results with X-ray diffraction patterns indicates that the maxima of the photocurrent and trap depth calculated from TSC measurements depend on changes in crystallization rate and in-crease in particle size
Driftgeschwindigkeiten, Diffusionskoeffizienten und Temperaturen von Photoionen in Argon, Stickstoff und Sauerstoff / Drift velocities, diffusion coefficients and temperatures of photo-ions in argon, nitrogen and oxygen
Authors: Warneck Peter
Published: February 2015

Groups of ions were produced by photoionisation of argon, nitrogen and oxygen in a drift chamber, using as the light source a repetitive spark discharge in combination with a uv monochromator. After their traversal of the drift region, the ions were detected in a mass spectrometer. An analysis of the temporal arrival profiles provided ionic drift velocities and diffusion coefficients as a function of gas pressure and electric field. For ions in their electronic and vibrational ground states, the measured drift velocities are in accord with previous data in the literature. At some wave lengths excited ions are produced in addition to ground state ions. Their drift velocities are larger on account of smaller charge transfer cross sections. Drift velocities and diffusion coefficients pro-vide ion temperatures as a function of the reduced field strength. Ion temperatures for argon ions correspond to the gas temperature. For nitrogen and oxygen ions the temperatures increase linearly with E/P and extrapolate at high fields to those given by Wannier's theory
Über den Fallraum in einer zylindrischen Hohlkathode / On the Cathode Fall in a Cylindrical Hollow Cathode
Authors: Helm H. , Howorka F. , Pähl M.
Published: February 2015

The electric field distribution in the cathode fall and the current-voltage characteristic of a cylindrical hollow cathode are calculated on a purely radial model. The theoretical characteristic is compared with results measured on a H2-and Ar-discharge. From the experimental data, the current density ratio of electrons and ions on the cathode can be calculated. This ratio appears in the correct order of magnitude only if the carrier generation in the cathode fall is taken into account.

Comparisons are made with the results of linear theories.
Einfluß des Anions auf das Lumineszenzspektrum kristallisierter Chrom(III)-Antipyrin-Verbindungen / The Influence of the Anion on the Luminescence Spectrum of Crystallized, Chrom(III)-Antipyrene Compounds
Authors: Koglin E. , Ervens H. , Krasser W.
Published: February 2015

The 4T2g→4A2g-and 2Eg→4A2g-transitions of the compounds [Cr(atp)6]X3 (atp=antipyrene; X: SO3F; BF4; SCN; ClO4) are investigated in the temperature range of 150 °K to 4.2 °K.

At temperatures higher than 80 °K the broad fluorescence transition 4T2g→4A2g dominates the 2Eg→4A2g phosphorescence transition.

With the exception of the thiocyanate compound, in all complexes the fluorescence transition is quenched at 4.2 °K.

We do not observe a splitting of the 2Eg-level. The measured Raman-and IR-vibrational bands can be assigned to corresponding vibrational side bands of the 2Eg→4A2g transition in the luminescence spectrum.
On Charge Separation at the Phase Boundary Molecular Crystal/Aqueous Electrolyte
Authors: Michel-Beyerle M. E. , Haberkorn R.
Published: February 2015

Analysis of the electrostatics of charge carrier injection into molecular crystals during nonequilibrium electron transfer reactions demonstrates the unique advantage of aqueous or similar electrodes in measuring limiting currents which yield the rate constant of the injection process. At the phase boundary molecular crystal/aqueous electrolyte image forces are negligible due to the slow orientation polarization of water molecules with respect to the hopping frequency of injected charge carriers. Coulomb forces arising from slowly mobile or localized counter charges are shown to be effectively screened by water as a consequence of its relatively higher static dielectric constant as compared to that of the crystal.
Notizen:Hyperfeinstruktur von CsCl
Authors: Hoeft J. , Tiemann E. , Törring T.
Published: February 2015

The quadrupole hyperfine structure of 133Cs35Cl was measured on the rotational transition J=1 → 2 at 8.6 GHz. The calculated quadrupole coupling constants of 35Cl in various vibrational states are reported. The observed line width of the rotational transitions yields an upper limit of the quadrupole coupling constant of 133Cs.
Notizen:Mischungsenthalpien beim flüssigen System Wasser + Essigsäure / Heats of Mixing for the Liquid System Water + Acetic Acid
Authors: Haase R. , Steinmetz P. , Dücker K.-H.
Published: February 2015

Calorimetric measurements of the heats of mixing for the liquid system water+acetic acid at 17 °C, 20 °C, 25 °C, 30 °C, 40 °C, and 50 °C show that there is a change of sign in the function H̅E(x), where H̅E denotes the molar heat of mixing and x the mole fraction of acetic acid. The process of mixing the pure liquid components is weakly exothermic for low acid concentrations, but strongly endothermic for high acid concentrations. The function H̅E can be approximately represented by the usual power series with respect to x, five free parameters at each temperature being necessary.
Notizen:Kinetics of Ester-interchange between Methyl Acetate and Ethanol
Authors: Rao T. , Gandhe B.
Published: February 2015

Kinetics of ester-interchange between methyl acetate and ethanol has been studied in the range 80 - 105°, using gas chromatographic technique. The reaction is of the second order, and the specific reaction rate is 29.6-10-8 l/mole-sec at 105°. The energy of activation is 16.7 kcal/mole and the en-tropy of activation is -44.3 cal/mole-deg.
On the Calculation of Vector Mesons in Functional Nonlinear Spinor Theory
Authors: Bauhoff W. , Scheerer K.
Published: February 2015

Nonlinear spinor theory is fomulated in functional space. An eigenvalue equation for mesons is derived. The group theoretical reduction of this equation is performed, especially the angular momentum decomposition. For vector mesons it is solved in first Fredholm approximation. A solu-tion corresponding to a physical particle is found contrary to earlier calculations. The calculated mass has the correct order of magnitude.
A Generalized Effective Interaction
Authors: Bolterauer Hannes
Published: February 2015

We discuss the possibility of neglecting poles of the effective interaction defined in a previous paper. In order to use model spaces which are not completely known we generalized the definition of the effective interaction considering as an example the self energy operator for the retarded Green-function.
Induzierte Stoßprozesse
Authors: Fröhlich G. , Sewing K. H.
Published: February 2015

Similar to the stimulated emission in radiation processes there are stimulated collisions in col-lision processes too. These stimulated collisions do not lead to an amplification of the electron tran-sitions like in radiation processes but attenuate the transitions. So the occurance of stimulated collisions can stabilize the population density of the levels.
Ein neues Verfahren zur Messung der radialen Temperaturverteilung in inhomogenen und instationären Plasmasäulen mit erheblicher Selbstabsorption / New Technique for Measuring the Radial Temperature Distribution in Inhomogeneous and Instationary Plasma Columns with Considerable Self-Absorption
Authors: Meiners D. , Weber W.
Published: February 2015

The complete lateral distributions of emitted intensity and optical thickness of the instationary plasma column are measured simultaneously by probing the plasma with its own radiation and recording both distributions on a single high-speed spectrum. From these lateral distributions the radial distributions of the coefficients of emission and absorption are calculated and by application of Kirchhoff's law the radial temperature distribution is determined. This new technique has been applied to an exploding wire plasma with 37 000 K on the axis. The mean deviations of three tem-perature distributions obtained by independent measurements at different wavelengths are less than 3 per cent.
Intramolecular Dipole Reorientation of Amino Compounds and their Interaction with Solvent Molecules. I
Authors: Eloranta Jaakko
Published: February 2015

The dielectric absorption of dilute solutions of aniline, methyl substituted anilines, chlorine substituted anilines, N,N,N',N'-tetramethyl-p-phenylene diamine and 4-aminobiphenyl in various sol-vents has been measured between 0.3 and 135 GHz. The measurements have been carried out at 20 °C and for some mesitylene solutions also at -30 °C and 60 °C. The absorption curves have been resolved into multiple absorption regions. A far infrared (FIR) term had to be included in each analysis. Its contribution to the total dipole reorientation depends on the solvent and on the mobility of the substituted groups in the phenyl ring. The obtained group relaxation times are longer than those reported previously and also their weight factors are smaller. Differences in the mobility of the amino group are observed in methyl substituted anilines. Methyl substituents in the amino group itself strongly reduce the mobility. The decrease in the group mobility parallels the increasing mesomeric interaction between the lone pair electrons in the nitrogen and the Π-electrons of the phenyl ring. In addition to the reorientation of the amino group of 4-aminobiphenyl another internal reorientation process is found which is attributed to a mesomeric charge shift. In-dications are obtained for weak association between some amino compounds and mesitylene.
A Mechanism for the Optical Nuclear Spin Alignment in Zero Magnetic Field
Authors: Colpa J.P. , Stehlik D
Published: February 2015

The Optical Nuclear Polarization (ONP) in molecular crystals is a consequence of the selective population and depopulation of the electronic magnetic sublevels of optically excited triplet states due to symmetry selection rules for the mixing of electronic states by spin orbit coupling. Two ONP-mechanisms have been proposed on this basis: The "relaxation"-mechanism, analogous to the Overhauser-effect, treats the optically produced distribution over the electronic magnetic sublevels as a steady state polarization which is transferred partially to the nuclear spin states via suitable hyperfine relaxation. The "crossing polarization"-mechanism takes into account in addition the mixing of states due to the hyperfine interaction in the electronic intersystem crossing processes. In this paper the latter mechanism is extended to a complete description of the dynamics of population and depopulation of the electronic and nuclear spin levels by including also all relaxation processes among the magnetic sublevels. It is shown that only in the extended form the mechanism can account for the experimentally observed optical nuclear spin alignment in zero external field.
Single-Particle States of Heavy and Superheavy Nuclei in a Velocity-Dependent Potential
Authors: Lodhi M. A. K.
Published: February 2015

Single-particle energy calculations have been performed for some closed shell heavy and superheavy nuclei using a form of an effective velocity-dependent nucleon-nucleus potential. Results are compared with other calculations and experimental data wherever available.
Investigations on the CS2—O2 Chemical Laser
Authors: Sadie F. G. , Büger P. A. , Malan O. G.
Published: February 2015

The reactions producing vibrationally excited CO in the continuous wave CS2 - O2 chemical laser are considered. Fundamental and overtone transitions were observed in the systems CS2 + O2, CS2 + N2O, O2 + CS and it is concluded that the two reactions O + CS → CO+S and O2 + CS → CO + SO are the reactions in which vibrationally excited CO are produced. The second reaction appears to be responsible for overtone laser action at low buffer gas partial pressures and low discharge currents.
Thermische Resonatoreffekte in organischen Farbstofflasern / Thermal Resonator Effects in Oiganis Dye Lasers
Authors: Zeidler G.
Published: February 2015

Thermal resonator effects are studied in laser pumped organic dye lasers with the longitudinal pumping arrangement. If the distribution of the pump light is a Gaussion, a diverging lens is induced by the thermal gradient in the dye solution. This thermal lens was compensated by using a suitable resonator set-up with an adjustable telescope. Divergence and bandwidth of the tunable laser were reduced considerably by using the proper compensation. If the angular position of the pump beam is shifted, the axes of laser resonator and thermal lens are different, causing beam deflection and wavelength shifting of the output laser beam. Therefore, high stability and mode purity of the pump laser is important to get a well defined output laser beam.
Molekülstrukturbestimmung von Trimethylazidosilan mittels der Elektronenbeugung an Gasen
Authors: Dakkouri Marwan , Oberhammer Heinz
Published: February 2015

The molecular structure of Trimethylazidosilane, (CH3)3SiNαNβNω, was determined by electron diffraction of gases. In contrary to published results this molecule has neither C3V- nor Cs-symmetry but C1-symmetry. The following results for the geometrical parameters were obtained:

ra(Nω-Nβ) =1.150 Å±0.011, ra(Nβ-Nα) =1.198Å±0.008, ra(Si-N)=1.734Å±0.007, ra(Si-C)=1.854Å±0.003, ra(C-H)=1.082Å±0.003,

∢Si-Nα-Nβ=128°±l.6°, ∢ᵨ=36.2°±4.9°

(ᵨ is the out-of C1SiNα-plane angel of the Azidodiaine about thel Si - Nα-bond),

∢Nα-Si-C1=107o±3.1o, ∢Nα-Si-C2=110.1°±3.2 ,∢Nα-Si-C3 = 105.2°±2.6°,

∢C1-Si-C2=110.4o±2.9°, ∢C1-Si-C3=108.8o±3.1°,

∢C1-Si-C3=115°±3.4°and ∢Si-C-H=114.2°±1.6°.
The Anisotropic Polarizability of a few Aromatic Hydrocarbons
Authors: Liptay W. , Schlosser H.-J.
Published: February 2015

For sufficiently symmetric molecules without a permanent electric dipole moment, it is shown that refractive indices, Kerr constants and electrooptical absorption measurements in suitable non-polar solvents can be utilized to determine the components αcgx, αgy, αgz of the polarizability tensor of solute molecules in the electronic ground state. Since the required quantities are avail-able for anthracene, tetracene, perylene and bianthryl, an evaluation of the polarizability tensor components is made possible.

In solutions where the solvent molecules possess a permanent electric dipole moment or a sufficiently large quadrupole moment, as for example benzene, the fluctuations of the reaction field cause a contribution to the Kerr constant which may be an essential reason for its solvent dependence.
Inkohärente Lichtstreuung an Ladungsdichteschwankungen schwach ionisierter Plasmen in Magnetfeldern / Incoherent Scattering of Light from Charge-Density Fluctuations in Weakly Ionized Magnetoplasmas
Authors: Klingenberg G. , Richter E. W.
Published: February 2015

The spectral density of light scattering from weakly ionized plasmas embedded in a homogeneous magnetic field Bis given by the work of WILLIAMS and CHAPPELL 1, 2 and KLINGENBERG 3 . The spectral density has been computed for electron plasmas and is analyzed for the case k ⊥B ( is the difference between the wave vectors of the incident wave and the scattered wave) in the regimes k D ≫ 1 and k D ≪ 1 (D is the Debye length).
Über einige Salze des Indiums V. Über die Indate
Authors: Ensslin Fritz , Valentiner Siegfried
Published: February 2015

Bericht über Herstellung und Kristallstrukturbestimmung einiger Indate, deren Eigenschaften, einschließlich Farbe und Feinbau, beschrieben werden.