bluuebunny/crossref_metadata_2025 huggingface dataset:
Prädissoziation im elektrischen Feld — ein neues Phänomen in der Molekülspektroskopie
Authors: Comes F. J. , Wenning U.
Published: February 2015

Molecules in certain excited states can be forced to predissociate in an external electric field. This effect will be shown to occur with H2 and D2. The molecular dissociation is made possible by an altered coupling mechanism as compared to the mechanism considered for the Kronig's selection rules. The interaction is a linear function of the field strength. It is further demonstrated that also molecular fields (van der Waal's fields) may cause the effect which is shown by the collision induced predissociation of the excited molecular states under consideration
Thermalisierung und zeitliche Entwicklung der Elektronendichte und Temperatur von Funkenkanälen in Wasserstoff
Authors: Tholl H.
Published: February 2015

In a streamer initiated pre-discharge channel in H2 the axial and radial electron density distributions were measured at different times of the channel development. It was found that at any point in the channel where the electron density reaches ≅ 2 - 1017 cm-3 an immediate thermalisation of the plasma at this point takes place in a time of ≅ 10 nsec. Due to the inhomogeneous radial and axial electron density distribution in a streamer initiated discharge channel the thermalisation begins at first in a constricted region of the channel. The further development of the electron density and temperature distributions in the thermalized channel was studied by means of spectroscopic plasma diagnostic methods in channels initiated by different overvoltages. These experiments have shown that the inhomogeneous axial electron density distribution is equalized after a time of ≅ 100 nsec. The maximum electron density of ≅ 1 - 2 - 1018 cm-3 is reached in the channel axis immediately after the thermalisation of the channel whereas the temperature increases during the time of the highest energy input to the maximum of ≅ 5 - 6 • 104 °K
Messung der Ionentemperatur mit Hilfe des thermischen Doppler-Effekts an einer Wasserstoff-Lichtbogenentladung
Authors: Ludwig D. , Raeder J.
Published: February 2015

The radial ion temperature distribution in a 2600 amp hydrogen arc in a 30 kG axial magnetic field was measured spectroscopically with a Fabry-Perot interferometer by evaluating the half width of Doppler broadened carbon lines. As the admixture of methane had to be low, in order to prevent a strong reduction of the temperature on the axis, the intensities of the C III and C IV lines were relatively weak. Consequently an interference filter with narrow transmission band width was used instead of a spectrograph in front of the F.-P.-interferometer.

The broadening of the spectral lines, which were used for measurement, was caused mainly by the thermal Doppler effect. The rotation of the plasma and the macroscopical Doppler effect resulting therefrom did not disturb the measurements. The ion temperature, which was found to be 1.4 × 105 °K on the axis, was determined from the half width of the profiles of a C III spectral line.

Since the discharge was observed side-on, the measured integrated values were reduced to radial profiles by using appropriate inversion formulae.
Der Rotations-Zeeman-Effekt der l-Typ-Übergänge linearer Molekeln. OCS und HCN
Authors: Hüttner W. , Morgenstern K.
Published: February 2015

The high-field rotational Zeeman effect has been observed in several rotational transitions of the (010) vibrational state in OCS and HCN. The magnetic-field splittings are in agreement with a simple first-order energy expression which is derived to hold for the Zeeman energies of rotation-vibrational states of a linear polyatomic molecule showing rotational l-type-doubling. In this way, the presence of intrinsic magnetic moments in the π-vibrational states has been shown experimentally. The g-values along the molecular axis are gǁ
(010)= +0.061 ± 0.002 for OCS and gǁ
(010)=±0.38 ± 0.06 for HCN. No magnetic anisotropics could be detected within the plane perpendicular to the molecular axis. The other parameters measured are g⊥(010)= -0.0285 ± 0.0006 and (χ⊥ - χǁ)(010) = (8.0 ±1.0) × 10-6 erg/G2mole for OCS and gǁ
(010) = ∓ 0.100 ±0.001 for HCN which "can be considered an approximate value for the vibrational ground-state. Either the upper or the lower signs hold for the g-values of HCN. The intrinsic g-values, gǁ
(010) , are discussed in terms of nuclear and electronic contributions. A quantity measuring the slip of a rotating nuclear framework within its electronic environment is defined and also discussed.
Eine Berechnung des 5∑u
- -Zustands des B2-Moleküls
Authors: Kockel B .
Published: February 2015

Der 5∑U
--Zustand des B2-Moleküls wird beredinet durch Überlagerung von 25 Konfigurationen, die vier K-Schalen-Elektronen und aus den beiden L-Schalen vier σ- und zwei π-Elektronen enthalten.
Ein Level-Crossing-Experiment im angeregten (5p1/2 5d5/2)J=2-Term des Sn I zur Untersuchung der Energieverschiebungen im elektrischen Feld / Level-Crossing Experiment in the Excited (5p1/25d5/2)J=2-State of the Sn I for the Investigation of the Energy Shifts in an Electric Field
Authors: Zimmermann P.
Published: February 2015

Observing the change of the Hanle effect under the influence of a homogeneous electric field E the Stark effect of the (5p1/25d5/2)j=2-state in Sn I was studied. Due to the tensorial part β Jz
2E2 in the Hamiltonian of the second order Stark effect the signal of the zero field crossing (M ∓ 2, M′ = 0 β ≷ 0 ) is shifted to the magnetic field H with gJμBH=2 | β | E2. From these shifts for different electric field strengths the value of the Stark parameter

|β| = 0.21(2) MHz/(kV/cm)2 · gJ/1.13

was deduced. A theoretical value of ß using Coulomb wave functions is discussed.
Field-dependent Mechanism of Anomalous Proton Conductivity and the Polarizability of Hydrogen Bonds with Tunneling Protons
Authors: Weidemann E. G. , Zundel G.
Published: February 2015

The displacement of the excess charge of the proton in acid solutions is caused by a structure migration of groupings H5O2
+ or H9O4
+ . The processes which take place during structure migration are discussed on the basis of results gained in IR-investigations. In an electrical field the structure migration is given a preferred direction. The hydrogen bond with the tunneling proton in H5O2
+ and the grouping H3O+ in H5O2
+ become polarized. Comparison of both polarizabilities demonstrates that, contrary to previous assumptions, the polarization of the hydrogen bond is the field-dependent mechanism. This conclusion is reached upon calculating the polarizability of the hydrogen bond with a symmetrical double minimum potential well. It is shown that the polarizability is extremely large, being approximately two orders of magnitude greater than that of H3O+ . Despite the large polarizability, the shift of the weights of the proton boundary structures is very small for the external fields usually applied in conductivity measurements. It is demonstrated, however, that this slight shift is large enough for the structure diffusion to obtain a preferred direction consistent with the anomalous high proton conductivity.
Gas-solid Interaction
Authors: Sanesi Manlio , Wagner Vittoriano
Published: February 2015

The heats of adsorption on magnesium oxide of six linear chain alkanes (C4 to C9) , of the corresponding 1-mono-olefins and of the cyclic compounds cyclohexane, cyclohexene, 1.4-cyclohexadiene and benzene have been determined by gas-solid chromatography and extrapolated to zero surface coverage.

The values obtained with n-alkanes are linearly dependent on the carbon atom number. By comparison with previous results for alumina and silica-gel, it is seen that the dispersion-interaction adsorption potentials for the CH3- and CH2-groups take very close values on the three different oxides.

As for the cyclic molecules, a constant increment of about 1.40 kcal/mole in the heat of adsorption on MgO is observed when passing from cyclohexane to cyclohexene and from the latter to 1.4-cyclohexadiene, in full agreement with the rrsults for Al2O3.

The values for benzene are intermediate between those for cyclohexene and those for 1.4-cyclohexadiene. These results are interpreted in view of a specific interaction of electrostatic nature between surface hydroxyls and π-electron systems.

With linear 1-alkenes, the specific contribution becomes more apparent with increasing chain length, the difference in the heats of adsorption reaching a value of 1.50 kcal/mole for the pair 1-nonene n-nonane.
Zum Problem der Übergangsentropie bei der Dissoziation
Authors: Krauss L.
Published: February 2015

An investigation has been made to determine if TROUTON-PICTET's rule, valid for phase transitions, can be extended to dissociation processes for diatomic molecules. Comparing the entropy increase from the non-dissociated to dissociated states, a common law exists for all diatomic molecules examined.

If the procedure is performed at a certain “fix-point”, the maximum of the specific heats, an average value of approximately 30 cal/Mol · K for entropy gain results. Since the TROUTON-PICTET rule is a consequence of the theorem of corresponding states and has been found only for phase transitions, the above results lead to the assumption that the new law can be seen as an extention of the TROUTON-PICTET rule applicable to all types of “state transitions”.
Wellenausbreitung in einem offenen thermodynamischen System zeitlich veränderlicher Gesamtenergie / Wave Propagation in an open Thermodynamic System with Time Variation of the Total Energy
Authors: Freund H.-D. , Locke G.
Published: February 2015

The absorption and dispersion of sound due to dissipative phenomena such as diffusion, heat conduction and viscous flow have been investigated by Herzfeld, Litovitz and others. Whereas in these studies the total energy of the carrier system remains constant, we consider the case that it is changing. It turnes out that the wavelength X remains constant, while all other wave characteristics become time depend and can be connected with the usual sound velocity of the carrier system

.

.

The change in energy density takes place via the potential energy. Thus the original balance between potential and kinetic energy is disturbed. Modulation vibrations of the wave amplitudes around the time averages arise. In addition dephasing of the pressure and density components with respect to the acoustic velocity takes place. The phasevelocities are disturbed too. They differ from time dependence of c(t).

These differences are running asymptotically towards zero, i. e. after a longer period of time a phase step remains of the total wave system. This phase step is negative for increasing energy of the carrier system and positive for decreasing energy. The value of the phase step is proportional to the wavelength λ, i. e. systems of this kind show dispersion.
Einfluß der Zusammensetzung von Natrium-Legierungen auf die Kernresonanzfluoreszenzausbeute von eingebauten Mg24 -Kernen
Authors: Dutta B. C. , Kalus J. , Schreckenbach K. , Shaukat M. A.
Published: February 2015

Beim Zerfall von Na24 entstehen angeregte niederenergetische Mg24-Rückstoßkerne mit einer kinetischen Energie bis zu ca. 170 eV.

Die Eigenschaften der nächsten Umgebung dieser Rüdestoßkerne beeinflußt in Festkörpern oder Flüssigkeiten stark deren Abbremsung. Für verschiedene Temperaturen von Na -Bi-, Na -Pb- und Na -Li-Legierungen und damit für verschiedene mikroskopische Umgebungen der Mg24-Rückstoßkerne wurde die relative Kernresonanzfluoreszenz (KRF)-Ausbeute, die von der Abbremsung der Rüdestoßkerne abhängig ist, gemessen. Es ergaben sich stetige und unstetige Änderungen in der KRF-Ausbeute, die bei der Na -Bi-Legierung bis zu 50% betragen. Die Änderungen werden an Hand der Phasendiagramme erläutert.
A Multiple Scattering Theory of Thermal-diffuse Scattering for Low-Energy Electrons
Authors: Moon Anthony R.
Published: February 2015

A perturbation theory of thermal diffuse scattering of low-energy electrons is developed along the lines of von Laue's “reciprocity theorem” approach successfully used by Kainuma in the consideration of diffuse scattering in high-energy electron diffraction. This theory takes into account the multiple scattering of the electrons within the crystal, and is so formulated that it may be used in conjunction with present LEED calculations for the elastic scattering from a perfect crystal. It is shown that by a pseudokinematical approximation for the perfect crystal wave functions, the normal pseudokinematical result for the diffuse intensity is obtained. Under certain conditions differences between the multiple scattering theory and the pseudokinematical theory are expected to occur. These deviations have their origin in resonance processes. Some numerical results comparing the two theories are presented.
Der Einfluß einer streuenden Phasenplatte auf das elektronenmikroskopische Bild
Authors: Badde H. G. , Beimer L.
Published: February 2015

Using carbon films for phase shifting in the focal plane of the objective one has to consider the decrease of the coherent part of the electron beam. Only the unscattered part contributes to the phase contrast. After passing a 90.8 nm carbon film with a phase shift of 2 π the coherent amplitude decreases to 47%. But using a phase plate of different thickness for shifting all scattered electrons like a Zernike λ/4-plate, there will be a larger increase of contrast in images of platinum and carbon atoms than by optimal defocussing phase contrast. Calculations of phase shift and decrease of zero beam amplitude up to 1 MeV are reported. The use of Be-films with lower scattering cross section offers no large advantage.
SCF-Rechnungen ohne vorgegebene Basis am Beispiel BH3
Authors: Frühbeis Horst , Seelig Friedrich Franz
Published: February 2015

Approximate solutions of the original Hartree-Fock-equation for the ground state of closed-shell molecules of arbitrary symmetry are attained by a combined numerical-analytical method. In a first step the one electron Schrödinger-equation for a conveniently guessed potential is solved by a numerical method described in previous papers. These MOs are approximated by linear combinations of basis functions of Gaussian type (GTF) in a variant of curve fitting varying all parameters of the GTFs. Principally they serve only to calculate the Coulomb and exchange potentials that are fed back into the conventional iterative procedure, but they can be used as an optimum basis set derived in an independent manner. Computations are made by a Fortran-IV program whose structure is briefly sketched. BH3 is used as a test substance.
Untersuchungen über das Verhalten der chemischen Bindung im elektrischen Feld. III
Authors: Drossbach P. , Schmittinger P.
Published: February 2015

Es wurden nach dem SCF-MO-LC (LCGO)-Verfahren das H2O-Molekül mit allen seinen Elektronen bei 5 verschiedenen Kernlagen sowie 3 verschiedenen Feldstärken in 6 verschiedenen Richtungen mit 41 Gauß-Funktionen; das H3O+ -Ion mit 44 Gauß-Funktionen unter Variation des Abstandes eines H-Kerns; das System H2O - H + - Li- bei festem O -Li-Abstand unter Variation des Abstandes des H+ ; und schließlich verschiedene Lin bei n = 2 bis n = 22 berechnet.
Messung der Streuquerschnitte von flüssigem und festem Wasserstoff, Deuterium und Deuteriumhydrid für thermische Neutronen
Authors: Seiffert W. D. , Weckermann B. , Misenta R.
Published: February 2015

The total cross section for thermal neutrons of liquid and solid normal-hydrogen, para-hydrogen, deuterium and deuterium hydride have been measured at several temperatures. The cross section of the liquid and solid phase of para-hydrogen shows that the para-hydrogen molecule scatters coherently. The coherence effects in the cross sections of liquid para-hydrogen and deuterium indicate a short range order of the molecules in the liquid.

The cross sections of para-hydrogen and deuterium hydride show clearly the excitation of the first rotational level of the molecule. The threshold indicates that the molecules of the liquid phase are not completely free. The cross section of liquid and solid para-hydrogen for neutrons with energies larger than the threshold energy show a different behaviour that can be explained by the different dynamics of liquid and solid.
Theorie einer zylindrischen Photoionisationskammer hoher Dichte
Authors: Gronig Hans
Published: February 2015

Es wird die Theorie einer zylindrischen Photoionisationskammer bei großer Dichte und kleinem Ionisationsgrad entwickelt. Unter den zugrunde gelegten Voraussetzungen läßt sich das Problem auf die simultane Lösung der mit Produktionstermen behafteten Kontinuitätsgleichungen für Ionen und Elektronen und der Poisson-Gleichung reduzieren. Physikalisch ist der Bereich zwischen den Elektroden durch drei Zonen gekennzeichnet: die beiden Raumladungsgrenzschichten an den Elektroden und das quasineutrale Gebiet dazwischen. Mathematisch ergibt sich eine analoge Aufteilung durch eine asymptotische Entwicklung der dimensionslosen Grundgleichungen nach einem sehr großen Parameter a. Man erhält explizite Lösungen für die Stromspannungs-Charakteristik, die Sättigungsströme und die Teilchendichten. Die Kenntnis dieser Größen legt es nahe, die Photoionisationskammer für die Eichung von Langmuir-Sonden zu verwenden
Nuclear quadrupole resonance of 14N in ethylenimine
Authors: Ha Tae-Kyu , O’Konski Chester T.
Published: February 2015

The nuclear quadrupole resonance (NQR) spectra of 14N in ethylenimine have been detected at 77 °K. Comparing to the reported microwave experiment on the gaseous state, it is found that the solid state shift in the quadrupole coupling constant is much smaller than that of ammonia
Optische Elektronenspin-Polarisation (OEP) in Triplett-Zuständen organischer Moleküle
Authors: Sixl H. , Schwoerer M.
Published: February 2015

Stimulated microwave emission is observed in the ESR spectrum of 2-methyl-naphthalene and anthracene molecules in their triplet states at 4,2 °K. This is the consequence of a strong deviation from thermal equilibrium distribution within the three magnetic sublevels, a phenomenon called optical electron spin polarization (OEP). The OEP is due to spin selection rules either during the population or during the depopulation processes of the triplet states. In most cases both processes occour predominantly radiationless and are termed intersystem-crossing (ISC).

In the present paper we report in detail about the kinetics of population, depopulation and spin-lattice relaxation of the phosphorescent triplet states of 2-methyl-naphthalene and anthra-cene. In addition the kinetical constants, the fine structure constants and the orientation in the host crystal of eleven different metastable triplet state molecules are presented in a table.

As opposed to former investigations (quinoxaline, naphthalene, pyrazine) spin polarization in 2-methyl-naphthalene and anthracene is due to the selectivity of the depopulation mechanism. This is demonstrated by the time dependence of the ESR-signals after switching on and off ex-citation light. The evaluation of the experiments yields a common rule concerning the intrinsic zero-field decay rate constants of naphthalene, 2-methyl-naphthalene and anthracene:

kx : ky : kz ≈ 2 : 1 : 0,2

The selectivity of the population decreases in the sequence naphthalene, 2-methyl-naphthalene, anthracene.
Über Probenpräparation, Oberflächenzustand und Kristallbaufehler von einkristallinem β-rhomboedrischem Bor/ On Sample Preparation, Surface Conditions and Lattice Defects of Monocrystalline β-Rhombohedral Boron
Authors: Binnenbruck H. , Hausen A. , Runow P. , Werheit H.
Published: February 2015

By use of an etching solution of 70% by weight H2O, 22% K3[Fe(CN)6] and 8% KOH largely plane sample surfaces can be obtained, the quality of which corresponds to electrolytically polished metal surfaces. A possibly existing crystalline surface layer does not exceed a thickness of 25 Å. The method is suitable for preparing extremely thin samples, which are transparent for visible light and high energy electrons. X-ray investigations and electron micrographs indicate lattice defects of great concentration in the available monocrystals.
Unipolar Flow of Charge Carriers in a Dense Gas with and without Consideration of Diffusion
Authors: Dällenbach W.
Published: February 2015

The basic equations for the unipolar, stationary, one-dimensional flow of charge carriers in a dense gas, characterized by mobility and diffusion coefficient, can be integrated numerically. The discharge gap generally has a finite length; as far as in the end cross-section either density of particles and intensity of electric field tend towards infinity, or the density of particles becomes zero. Which of these two cases occurs depends on the current density of the discharge and on the intensity of the electric field in the initial cross-section. The notions mobility and diffusion coefficient will lose their applicability close to a pole like singularity as well as in a "dilution to zero", so that from a certain cross-section onwards the continuation of discharge is determined by modified equations.

It is shown that in case the diffusion component of the current density is neglected, the integrals of the basic equations change fundamentally. Neglecting the diffusion is inadmissible. This is finally a consequence of the relationship between mobility and diffusion coefficient, as expressed by the Einstein-relation.
Strukturbestimmung des N-Chlor-Sulfinylamins mit Hilfe der Elektronenbeugung an Gasen
Authors: Oberhammer Heinz
Published: February 2015

Mit Hilfe der Elektronenbeugung wurde die Molekülstruktur des N-Chlor-Sulfinylamins in der Gasphase bestimmt. Folgende Werte für die geometrischen Parameter wurden erhalten:

N-Cl=1,696±0,003 Å, S-N=1,559±0,004 Å, S-O=1,445±0,004 Å,

∢ ClNS=116,3±0,4°, ∢ NSO=116,0±0,6°.

Das Chloratom steht in cis-Stellung und ist um einen Diederwinkel von ϱ = 35,5 + 3,6° aus der NSO-Ebene herausgedreht. Die Schwingungsamplituden wurden aus spektroskopischen Daten berechnet und werden mit den experimentell bestimmten Werten verglichen.
Zur Vereinfachung thermodynamischer Rechnungen Das "Stürzen" einer partiellen Ableitung
Authors: Job G.
Published: February 2015

Durch die Einführung einer neuen einfachen Operation zur identischen Umformung von Differentialausdrücken läßt sich der Arbeitsaufwand bei thermodynamischen Rechnungen stark verkürzen und das Ergebnis vieler Aufgaben häufig in einer Zeile unmittelbar aus den Definitionsgleichungen der vorkommenden Größen ohne Rückgriff auf früher abgeleitete Beziehungen und ohne Zwischenrechnung aufstellen. Sämtliche Reziprozitätsbeziehungen der klassischen Wärmelehre und der Thermodynamik irreversibler Prozesse können in einem einzigen Rechenschritt zusammengefaßt werden, so daß sich der Formalismus der thermodynamischen Potentiale weitgehend erübrigt.
Notizen: Pion Finite Size and Mesic Atoms
Authors: Daniel H.
Published: February 2015

Contrary to the point-like muon the pion has a spatial extension. The effect of this finite size on levels of π-mesic atoms is estimated to be small but not necessarily negligible.
Notizen: The Effect of Carrier Concentration on Microwave Emission from n-Type Indium Antimonide
Authors: Porter W. A. , Ferry D. K.
Published: February 2015

The effect of carrier concentration on the threshold for microwave emission from InSb was determined. Threshold electric fields are lower for higher concentrations and the magnetic field dependence is reduced.
Lassen sich Quantenzustände als Ensembles streufreier Zustände darstellen? I/Can quantum-states be considered as ensembles of dispersionfree states? I
Authors: Ochs W.
Published: February 2015

We consider the problem, whether quantum-states can be represented by Gibbsian ensembles of dispersionfree microstates having well defined values for all observables. Such a statistical representation is shown to be possible if and only if the concept and mathematical representation of observables is modified by abandoning the 1-1-correspondance between observables and operators. A particular representation of quantum-states by Gibbsian ensembles is constructed.
Resonant Approximation for Single-Particle Resonances in the Renormalized RPA-Problem
Authors: Weigel M.
Published: February 2015

An approximate version of the renormalized RPA-treatment for scattering of nucleons on a hole nucleus is given, in which the shape resonances are treated according to a method of BALASHOV et al. In order to make the results more transparent we take into account the additional influence of the non resonant part of the single-particle continuum with the help of a separable particle-hole force.
Die Verlagerung wandstabilisierter Lichtbögen durch Krümmung/The Displacement of Wallstabilized, Electric Arcs by Curvature
Authors: Nathrath Norbert
Published: February 2015

If an electric arc is forced to burn in a curved line by a toroidal container its position is displaced in direction to the center of curvature due to the inhomogeneous ohmic heating and of the cooling by conduction. The self magnetic-field pushes the arc outwards. Corresponding measurements in Argon at atmospheric pressure with currents from 0.5 to 20 A yield tbe excentric positions depending on current and curvature. The measured functions compare favourably with theory, but only if the deviation from LTE in the calculation of electric conductivity is taken into account.
Die Zerfallskinetik und kritische Konzentration des Peroxyds (H2O2 + UO4 ) in der Brennstofflösung eines wäßrig-homogenen Kernreaktors
Authors: Ehn E. , Tamberg T.
Published: February 2015

Die ohne UO4-Ausfällung erreichbare, maximale stationäre Leistungsdichte bei 40, 60 und 80° wurde für den Fall der im Berliner Kernreaktor (BER) benutzten Brennstofflösung ermittelt. Außerdem wurden die Geschwindigkeitskonstanten der Peroxydzersetzungsreaktion in Abhängigkeit von der Temperatur gemessen und die ohne UO4-Ausfällung noch einstellbare Peroxydkonzentration errechnet. Experimente zur Kinetik der UO4-Ausfällung und -Auflösung zeigten, daß beide Vorgänge stark gehemmt verlaufen und mit Über-bzw. Untersättigungserscheinungen verbunden sind.
On Dielectronic Recombination
Authors: Ansari S.M.R. , Elwert G. , Mücklich P.
Published: February 2015

The derivation of a general formula for the coefficient of dielectric recombination is reviewed, and approximate formulae known in the literature are discussed. With the aid of Burgess' simplified formula calculations of the coefficient of dielectronic recombination for the elements C, O , Ne, Mg, Si, S and Fe in the temperature range 108 - 4 x 106 °K are performed. The results are presented in figures and in tabular form. Taking into account dielectronic and radiative recombination, the ionization equilibrium for the various stages of these elements is determined and compared with recent results of other authors.
Ion-Slip Coefficients for Partially Ionized Argon and Helium
Authors: Wang H.S.C.
Published: February 2015

Ion-slip coefficients in Demetriades and Argyropoulos' generalized Ohm's law are studied quan-titatively in the first approximation for partially ionized Ar and He under various non-isothermal gas conditions. The macroscopic forces due to collisions between electrons, ion, and neutral atoms are accounted by averaging the momentum transfer cross sections over the Maxwellian velocity distributions of the colliding particles. To incorporate the appropriate interpolation and extrapola-tion techniques in the low energy limit, Frost and Phelps' cross sections for electron-atom collisions and Dalgarno's value for ion-atom resonant charge-transfer cross sections were used. The weighted average momentum transfer cross sections thus obtained, which are also important in other diffusion and transport processes, are tabulated at various particle kinetic temperatures for both gases. A family of curves representing values of ion-slip coefficients calculated from these data is plotted. With the generalized Ohm's law written in its inverted form, the influence of ion-slip on the "Hall conductivity" in Kruger et al's formulation is discussed.
A New Type of Apparatus for the Determination of the Thermal Diffusion Factor
Authors: Õost W .A.
Published: February 2015

In this article an apparatus is presented which gives a precisely known multiplication of the elementary effect in thermal diffusion experiments, avoiding the drawbacks of the swing-separator (Trennschaukel). This is achieved by using a different method of concentration nivellation than customary with the swing-separator, viz. thermosyphon action.
A Quasi-Universal Internuclear Potential Energy Function for the Diatomic Halides
Authors: Yeranos Walter
Published: February 2015

Taking into account the universal correlation of the force constants of halide bonds with their respective dissociation energies (excluding the fluorides), an internuclear potential energy function of the type V(r) = De (1-e-α(r-re))2 + β (1-δF,X) (r - re)2e-γ(r-re) has been proposed for the diatomic halides. α und β, in the latter are constants for a specific series, γ is determined from the rotational-vibrational constant αe, and the function reduces to the ordinary Morse potential function in the case of the fluorides. It, moreover, performs as well as the Hulburt-Hirschfelder 5-parameter function, and, unlike the latter, utilizes the anharmoni-city constant ωeXe as an internal check.
Chemically Induced Dynamic Nuclear Polarization
Authors: Fischer Hanns
Published: February 2015

NMR emission and enhanced absorption of products of radical reactions (CIDNP) is explained by nuclear spin dependent adiabatic transitions between singlet and triplet states of transient radical pairs. In magnetic fields larger than about 1 kG only S - To-transitions contribute to nuclear polarization. From a kinetic formulation of the pair mechanism equations for quantitative calculations of CIDNP patterns are derived.
Zum Mechanismus der Wärmeleitfähigkeit in Ni-und Ni—Cu-Legierungen
Authors: Tursky W. , Koch K.
Published: February 2015

Die Messungen der Änderung der Wärmeleitfähigkeit von Ni-und Ni —Cu-Legierungen im Magnetfeld bei Temperatu-ren unterhalb Raumtemperatur ergeben bis zur magnetischen Sättigung ein völlig paralleles Verhalten von X und o. Bei Stickstofftemperaturen zeigen sowohl die AX/X-als audi die zlö/ö-Kurven oberhalb der Sättigung eine Abnahme mit wach-sendem Magnetfeld, auf die bei weiterem Anstieg von H der normale dM/dH-Effekt folgt.
Hall-und Nernst-Effekt in Ni-und Ni—Cu-Legierungen
Authors: Weiser O. , Koch K.M.
Published: February 2015

DANNHÄUSER und KOCH 1 haben den Nernst-Effekt von Ni —Cu-Legierungen bei Raumtemperatur gemessen und ge-zeigt, daß er bis zu rund 30% Kupfer zunimmt, bei höheren Cu-Konzentrationen aber wieder abnimmt. Für den Hall-Effekt konnte NENTWICH 2 den gleichen Verlauf mit der Cu-Konzentration nachweisen, nur war hier der Abfall schon ober-halb 20% zu beobachten. Wir haben Hall-und Nernst-Effekt bei Temperaturen bis rund 350 °C gemessen und festgestellt, daß beide Effekte sowohl im reinen Nickel als audi bei den Ni —Cu-Legierungen anfangs mit der Temperatur zunehmen, bei einer reduzierten Temperatur T/Tc = 0,8 bis 0,9 (7c = Curie-Punkt) ein Maximum erreichen und dann rasch abneh-men.
Viscosity in an Electric Field of Mixtures of Polar Gases with Argon and Helium
Authors: Levi A.C. , Scoles G. , Tommasini F.
Published: February 2015

The influence of an electric field on the viscosity of mixtures of polar gases with argon and helium has been measured using a capillary bridge. The relative change of the viscosity coefficient η3 has been obtained in this way. A theory of the effect is sketched along similar lines to those followed by Tip for the magnetic case. The half value of the field is shown experimentally to be linear in the concentration. Moreover, a comparison of the experimental data with the theory yields cross section ratios of noble-polar collisions versus polar-polar collisions, both for the reorientation and for rotational energy transfer. The reorientation collision frequencies are compared to those obtained from non-resonant microwave absorption.
Der Einfluß der Primärmasse auf die Struktur großer Luftschauer
Authors: Thielheim K. O.
Published: February 2015

Results of Monte Carlo Simulations of Extensive Air Shower Development are discussed with respect to the influence of primary mass on shower characteristics (energy spectrum and lateral distribution of hadrons, frequency of nuclear active "multicores", mean total energy of hadrons, fluctuation of total hadron energy, mean total number of myons, fluctuation of total myon number, mean central electron density, frequency of electromagnetic "multicores"). Critical comments are presented concerning some empirical data.
Observations on Electrotransport in Thin Aluminum Films Using Resistance Measurements *
Authors: Hummel R. E. , Breitling H. M.
Published: February 2015

Resistance measurements of five different portions of uncoated and partially SiO-overcoated aluminum stripes are reported. In specimens of both types the resistance increases at the cathode when the stripe is subjected to high current densities. In partially coated specimens the resistance decreases at the anode whereas it remains constant in the uncoated sample. The difference in behavior at the anode between coated and uncoated specimens is interpreted as being due to dif­ferences of ion accumulation: In the uncoated films hillocks are formed whereas in the specimen with partial overcoat the ions accumulate more to support this interpretation
Correlation Effects and Activation Energies for Diffusion in Alloys
Authors: Manning John R.
Published: February 2015

The problems involved in calculating correlation factors for diffusion in dilute alloys can be contrasted to those arising in concentrated solid solutions. As one moves from the pure element to the dilute alloy to the concentrated alloy, the calculation becomes progressively more difficult. Because of the complex atom configurations which can occur in concentrated alloys, it usually is not possible to calculate correlation factors in these alloys exactly. Several important simplifications are available in non-dilute random alloys. A large reduction in complexity can be secured by using a random alloy model where each atom is treated as diffusing in a uniform matrix, with the matrix properties being determined by the composition and jump frequencies in the alloy. Resulting equations in this random alloy model can be expressed directly in terms of the experimentally measurable tracer diffusion coefficients with no unknown vacancy jump frequencies appearing. Also these equations have the advantage of being in simple analytic form and not requiring numerical methods to evaluate the correlation factors. These two features make possible the direct expression of the temperature dependence of the correlation factor in terms of the experimental activation energies.

Equations are found for ΔH/ΔQ in random binary cubic alloys, where AH is the difference between the activation enthalpies for diffusion of the two species and ΔQ is the difference between the experimentally measured activation energies of the two species. This ratio is never less than unity and can be much larger than unity. Values are plotted for diamond, body-centered cubic and face-centered cubic structures. From the magnitude and composition dependence of ΔH/ΔQ, it is concluded that the temperature dependence of the correlation factor cannot by itself explain the difference between the activation energies measured from tracer diffusion and from internal friction in the non-dilute range
The Velocity of Energy Transport for Normal Modes Near Total Internal Reflection
Authors: Nicolis John S.
Published: February 2015

The problem of the velocity of propagation of the various normal modes of a spherical electro­ magnetic quasi-monochromatic wave in a transparent layer near total reflection is examined, and a formula giving the velocity of the energy transport as a function of the eigenvalues of the modal equation is derived
The Influence of Deposition Conditions on the Photoconductive Properties of Chemically Deposited Lead Sulphide
Authors: Büger P. A. , Malan O. G. , Kunze O. A. , Fink W.
Published: February 2015

The influence of the deposition time and the ratio of hydroxide to lead ion concentration in the precipitation solution on the photoconductive properties of chemically deposited PbS layers was investigated.

From measurements of time constant, noise and resistance, it could be shown how the deposition conditions control the number of trapping centres and carrier density. The trapping centres may be connected with excess lead atoms deposited in the PbS lattice under the conditions of pre­paration
Supraleitung und Magnetismus in Mischphasen des Typs Mex Ce1-x Ru2 und Ce(Ru1-x Mex)2
Authors: Wilhelm M. , Hillenbrand B.
Published: February 2015

Es wird die Präparation von Mischphasen der Zusammensetzung MexCe1-x Ru2 (Me = Sc, Y, La, Pr, Nd, Gd, Tb, Dy, Ho, Er, Lu) und Ce (Ru1-x Mex)2 (Me = Cr, Fe, Rh, Pd, Os, Ir, Pt) be­schrieben. Für die La-, Pr-, Nd- und Fe-haltigen Legierungen wurde eine lückenlose Reihe kubi­ scher Mischkristalle gefunden. In Systemen mit Mischungslücken wurden die Löslichkeitsgrenzen ermittelt. Kubische Gitterkonstanten, Übergangstemperaturen zur Supraleitung Tc und Spinord-nungstemperaturen Θc werden mitgeteilt
Orthogonalitätsrelationen der mehrzeitigen erzeugenden Funktionale des Harmonischen Oszillators
Authors: Weber R
Published: February 2015

We treat the one-dimensional harmonic oscillator completely in the field theoretic calculus of many time generating functionals. Without the results of common quantum mechanics we compute eigen values and functionals of the energy preparing all information of the harmonic oscillator. As an example of functional integration and for applications in scattering theory we prove orthonormality relations of these functionals.
Die Mikrowellen-Rotationsspektren des AgCl, AgBr und AgJ
Authors: Hoeft J. , Lovas F. J. , Tiemann E. , Törring T.
Published: February 2015

The observation of the low lying rotational transitions J = 0 →1 of AgCl and J = 2→3 of AgBr resulted in improved quadrupole coupling constants: 107, 109Ag35Cl: e qν Q (35Cl) = -36,50 (10) MHz (ν=0,1); 107.109Ag79Br; e q0 Q(79Br) =297,10(15) MHz, e q1 Q (79Br) =297,65 (15) MHz. In con­trast to former measurements of KRISHER and NORRIS we obtained the following constants of 107Ag79Br: Y01 = 1943,6420 (50) MHz, Y11 = -7,0745(70) MHz, re = 2,393100(29) Å.

The unknown rotational spectrum of AgJ was found. Measurements of the transition J = 3 →4 in four vibrational states resulted in the determination of the following molecular constants:

Y01 = 1345,1105(25) MHz, Y11= -4,2389(30) MHz, Y21 = 1,70(80) kHz, Y0,=-0,2540(2) kHz; re = 2,544611 (31) Å; e q0 Q(127J) =-1062,17(40) MHz, e q1 Q(127J) = -1064,81 (40) MHz.
On the Calculation of Nonlinear Spinor Field Functionals
Authors: Stumpf H
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. Such operations have been defined in preceding papers. To apply these operations to physical problems, the corresponding functionals have to be known. Therefore in this paper calculational procedures for functionals are discussed. As high energy phenomena are of interest, the calculational procedures are given for spinor field functionals. Especially a method for the calculation of stationary and Fermion-Fermion scattering functionals is proposed.
Eigenfrequencies and Eigenvectors of Polaritons with Application to LiNbO3 I. Long Optical Phonons
Authors: Börstel G. , Merten L.
Published: February 2015

The properties of polaritons in uniaxial crystals with an arbitrary number of atoms in the unit cell are discussed in the harmonic approximation. For LiNbO3 , which seems to become a very important substance for applications in tunable Raman lasers, the complete set of eigenfrequencies and eigenvectors (normal coordinates, electric field, electric polarisation) is calculated numerically.

In the limiting case k→∞ (long optical phonons), which is treated in detail in this first paper, an example for each possible type of extraordinary phonon branches is discussed, namely a (T→L) -a (L→T)-, a (T→T)-and a (L→L) -branch of each type. The results are comparable with ex­perimental data only for the frequencies of the 45°-phonons, measured by Barker and Loudon. The agreement is very satisfactory.
Das Verhalten toroidaler elektrischer Lichtbögen / The Behaviour of Toroidal Electric Arcs
Authors: Wynands A. , Druxes H. , Schmitz G.
Published: February 2015

A wall-stabilized electric arc in an uniform bent tube is investigated. By the asymmetry of Ohmic heating and heat conductivity through the wall a displacement of the maximum of temperature is caused into the direction of the center of curvature, contrary to cylindrically symmetric geometries. By this an asymmetry of the thermal, electric and magnetic quantities is generated and produces a mass flux through the cross-section of the tube. A double whirl is formed by the self-magnetic Lorentz-forces.

This convectiv heat flow displaces the maximum of temperature bade into the direction of the outer wall. Both influences are investigated and the final position of the maximum of temperature is discussed in dependence on the arc parameters.

For numerical calculations the equations of continuity, motion, energy and the Maxwell's equa­tions of electromagnetic field are solved simultaneously. Results for a nitrogen plasma at nearly atmospheric pressure are presented.
Thermodynamische Analyse der binären Systeme des Germaniums mit Kupfer, Silber und Gold
Authors: Predel B. , Stein D. W.
Published: February 2015

For the purpose of carrying out a thermodynamic analysis of the binary systems of germanium with copper, silver and gold, the enthalpies of mixing of liquid Cu-Ge and Au-Ge alloys were determined at 1150 °C. Further the enthalpies of mixing of Ag-Ge solid solutions and the enthalpies of formation of the ζ and ε1 phases of the Cu-Ge system were obtained from the enthalpies of solution in liquid tin. It was possible to determine the enthalpy of transformation of germanium from its stable modification into a hypothetical, face-centered cubic structure (ΔHT(Ge) = 13.0 kcal /g-atom) which has a decisive influence on the stability of the solid phases in the systems under consideration. Liquid Cu-Ge alloys show energetic pecularities similar to those existing in the solid state and leading to the formation of electron compounds. A distinct influence of the valency difference of the components can also be demonstrated. In the gold-germanium system, however, the influence of the electronegativity difference of the components is dominant.
ESR Triplet Exciton Spectrum of Acridine Orange
Authors: Schmidt Hartmut
Published: February 2015

The triplet state of acridine orange dissolved in methanol/water matrix was investigated by ESR. In absence of oxygen a strong temperature dependence of the spectra was observed. At low temper­ature (100 °K) the zero-field splitting parameters calculated from the triplet spectrum are: X/hc = 0.0050 cm-1, Y/hc= 0.0342 cm-1, Z/hc=0.0387 cm-1 , at higher temperature (140 °K) : X*(hc=0.0056 cm-1, Y*/hc=0.0206 cm-1, Z*/hc = 0.0262 cm-1 . It was assumed that the low temperature spectrum is caused by isolated molecules in the triplet state while the high temperature spectrum must be attributed to the triplet exciton state of the acridine orange dimer. From the theory of the ESR triplet exciton spectra it can be shown that in the dimer state of acridine orange the molecular planes form an angle of 50° or 130°. However, it cannot be excluded that the dimer configuration differs in the ground or excited singlet state from the triplet state.
Notizen:Kernrückstoß in festen Stoffen und Knock-out-Effekt
Authors: Zimen K. E. , Mertens P.
Published: February 2015

H errn P rof. Dr. N ikolau s R ieh l zum 70. G ebu rtstag gew idm et In einer großen Zahl von Arbeiten 1 wurde die von 0 . Hahn eingeführte sogen. Emaniermethode benutzt, um Aussagen über Transportmechanismen und Fehlord­ nungen in festen Stoffen zu gewinnen. Nach der Theo­ rie dieser Methode2 setzt sich das Emaniervermögen, d. h. die Austrittswahrscheinlichkeit der Edelgasatome (e), zusammen aus einem Rückstoßanteil und einem Diffusionsanteil: £ = £ r + £ d . Der hier interessierende Rückstoßanteil ergibt sich nach 2, z. B. für ein kugel­ förmiges Korn, aus
Notizen:The G eneralised Mean Square Amplitudes of Vibration for Substituted Ethylenes Vinylidene Halides and their Deuterates
Authors: Jeyapandian S.
Published: February 2015

For six vinylidene halides the generalised mean square amplitudes of displacements parallel and perpendicular to the bond for both bonded and non-bonded atom distances are cal­culated from spectroscopic data using the method of Morino and Hirato. The results are discussed and the mean amplitu­des of these molecules (H2C=CX2) are compared with those from electron diffraction data for the similar molecules of the type C2X4.
Thermodynamik heterogener Gasgleichgewichte III. Gasphasenzusammensetzung und chemische Transportreaktionen im System Wolfram-Sauerstoff
Authors: Neumann G. M. , Gottschalk G.
Published: February 2015

Die Gasphasenzusammensetzung des heterogenen Systems Wolfram-Sauerstoff wurde mit Hilfe von Computerprogrammen für Temperaturen von 1500 -3600 °K und für Sauerstoff-Anfangsdrucke von 1 - 10-6 atm berechnet. Es zeigt sich, daß bei niedrigen Temperaturen (T<1600 -1900 K) neben festem Wolfram auch festes Wolframoxid vorliegt, so daß in diesem Temperaturbereich die Zusammensetzung der Gasphase unabhängig von den Sauerstoff-Ausgangsdrucken bleibt und nur durch das feste Wolframoxid bestimmt wird.

Im Bereich höherer Temperaturen (T >2000 K) findet in offenen Systemen ein chemischer Transport von Wolfram über seine Oxide statt. Die Transportrichtung verläuft zunächst von kalt nach heiß und kehrt sich bei sehr hohen Temperaturen um und verläuft dann von heiß nach kalt. Das Einsetzen der Transportreaktion und die Umkehr der Transportrichtung weist dabei eine Abhängigkeit vom Sauerstoff-Ausgangsdruck auf.

Die Berechnungsergebnisse werden durch experimentelle Beobachtungen der Literatur bestätigt.
Notizen: The Pyroelectric Effect in Lithium doped Cadmium Sulfide
Authors: Deeg W. , Gobrecht H. , Nelkowski H.
Published: February 2015

CdS crystals highly doped with Li, showing the tap-effect1 have pyroelectric constants considerably higher than those reported by MINKUS 2 for pure CdS crystals. The differences of the surface charges during cooling and heating can be ex­ plained by considering the exponential temperature dependence of the electric conductivity of the crystals.
On a Unified Theory of Twocentre Harmonic Oscillator Integrals
Authors: Wltschel W .
Published: February 2015

Twocentre harmonic oscillator overlap integrals (Franck-Condon-integrals) are calculated in a simple way for twodimensional oscillators of different frequencies. Second quantization and operator technique are applied. It is further shown that transition and kinetic energy integrals can be derived in the same representation.
Bemerkungen zur Phononen-Wechsel Wirkung in Polymeren
Authors: Baur H.
Published: February 2015

The stiffness of the polymer chains provokes a part of the acoustical low frequency phonons in polymer crystals to behave like free particles charged with mass, as far as their energy-momentum-relation is concerned. The influence of this "mass" on the 3-phonon-processes and on the phonon-electron-interaction in the isolated linear chain, in a Bravais lattice built up of linear chains, and in the isolated planar zig-zag-chain is investigated. It is shown that the "inert" phonons are especially exposed in the case of phonon-phonon-and phonon-electron-interaction.
Supraleitung der A 15-Phase im System Nb—Al—Si
Authors: Müller A.
Published: February 2015

Im System Nb -Al-Si mit mehr als 60 At.-Proz. Niob wurde der isotherme Schnitt bei 1840 °C untersucht. Im Bereich von 75 bis 80 At.-Proz. Niob und 0 bis 7 At.-Proz. Silicium existiert A 15-Phase. Phasenfeld und Gitterkonstanten sowie kritische Stromdichten und kritische Temperaturen der supraleitenden A 15-Phase werden mitgeteilt. Bei einphasigen Proben Nb75,3Al21.5Si3.2 wird im ternären System die höchste Sprungtemperatur von 19,2 K beobachtet.