bluuebunny/crossref_metadata_2025_split huggingface dataset:
Das Kernniveauschema von Yb 175
Authors: Breitig Dieter 
Published: February 2015

Abstract
The Yb174 (n,γ) -spectrum has been measured in the energy region of 26 -1500 keV. More than half of the observed 239 y-lines were placed in a level scheme. Precise energies have been determined for the states and their deexcitation has been studied in detail. New rotational bands, with the configurations { ([624 ↑]n + [512 ↑]n + [514 ↓]n)3/2 +[642 ↓]}, [651 ↓] and [642 ↓] are proposed at 1067, 1356 and 1937 keV. Calculations show that these bands strongly mix through Coriolis coupling. Additional and previously unknown states of the [624 ↑] and [633 ↑] bands are proposed. Level energies and y-branching ratios are explained reasonably well through a multi­ band mixing calculation of the configurations with negative parity.
Absolutbestimmung der kohärenten Streuamplitude von Schwefel und der totale Wirkungsquerschnitt für subthermische Neutronen
Authors: Trüstedt W.D. 
Published: February 2015

Abstract
Die Bestimmung der kohärenten Streuamplitude des gebundenen Schwefelatoms mit Hilfe des Neutron-Schwerkraftrefraktometers des Forschungsreaktors München ergab a = (2,847 + 0,001) F. Der totale Wirkungsquerschnitt von flüssigem Schwefel (135 °C und 176 °C) für Neutronen- Energien 4 · 10-3 > E > 0,15 · 10-3 eV wurde gemessen. Der Beitrag der Selbstdiffusion des Schwefels zum inelastischen Streuquerschnitt wird beredinet.
Hochenergetische Konversionselektronen und das Niveauschema von 200Hg
Authors: Mampe W. , Egidy T. von , Kaiser W. , Schreckenbach K. 
Published: February 2015

Abstract
Approximately 165 conversion electron lines from slow neutron capture in 199Hg have been measured with the beta spectrometer at the reactor FRM between 900 keV and 8 MeV. The high energy K-conversion coefficients of El and Ml transitions are separated distinctly and agree very well with theoretical calculations, which have been performed by several groups recently. High energy L-conversion electron coefficients have been measured for the first time with such a degree of accuracy that different multipole orders are separated and a comparison with theoretical values is possible. 6 known levels above 2 MeV have been assigned 1+ and 14 new levels have been established. 145 lines have been placed into the level scheme and new level energies have been calculated. A new 0+ level has been found at 1856.97 ± 0.1 keV.
Die plötzliche Kernladungsänderung als Anregungsmechanismus optischer Übergänge
Authors: Luchner K. , Parsche H. , Micklitz H. 
Published: February 2015

Abstract
The sudden change of nuclear charge (β-decay) produces a finite probability for the excitation of the outer electron shell. The emission spectrum of a gaseous Xe133-source exhibits light from the daughter Cs+, excited by the sudden change of nuclear charge, as shown by a spectral analysis. The probability for this excitation, p ∼ 6 · 10-2 per β-decay, is found in coincidence with the β-particles from the upper part of the β-spectrum; this value is lowered if also the low-energy part of the β-spectrum is included in observation; this seems to indicate a breakdown of the sudden approximation around 20 keV. The absolute values of p for Kr85 and Xe133 are discussed. The photon yield from the Kr85-decay in solid state for high Eβ is not a constant, as it is in the gaseous state, but decreases with Eβ , suggesting nonradiative transitions induced by the β-recoil.
Cross Section for "Ultracold" Neutrons I. Theory of Magnetic Scattering
Authors: Binder K. 
Published: February 2015

Abstract
Very cold neutrons (typical wavelengths are about 102 Å) are available by recently developed techniques 2. The features of the scattering of these “ultracold” neutrons are investigated in the present paper discussing a few examples of magnetic scattering. The diffraction of neutrons by the vortex lattice in superconductors is treated as an example of elastic scattering, while in most other cases the scattering is inelastic. We discuss the scattering by ferromagnetic magnons at low temperatures and the critical scattering from an isotropic ferromagnet above the critical tempera­ture. Simple models are used to derive the total cross sections. It is shown that relevant information about the inealsticity can be gained by the measurement of total cross sections in these cases.
Präzise Messung der totalen Wirkungsquerschnitte von Wismut, Blei, Silizium und Kohlenstoff für 130 eV-Neutronen
Authors: Dilg W. , Vonach H. 
Published: February 2015

Abstract
A precise transmission measurement of the cross sections of Bismuth, Lead, Silicone and Carbon for 130 eV neutrons (Co-resonance) has been carried out. A new resonance method has been applied, using epithermal reactor neutrons, which have been scattered twice from Co-foils. - We obtained the total 130 eV cross sections: Bi: 9,182 ± 0,007 b, Pb: 11,295 ± 0,009 b, Si:2,0442 ± 0,0018 b, C: 4,746 ± 0,007 b. From these results the coherent nuclear scattering lengths (bound), Bi: 8,646 ± 0,005 fm, Pb : 9,524 ± 0,004 fm, C: 6,660 ± 0,006 fm, have been calculated, under consideration of various corrections (absorption, Schwinger-scattering, Incoherence, Neutron-Electron-Interaction, energy-dependence of nuclear-scattering).
Untersuchung des Neutroneneinfang-Mechanismus in der Reaktion 80Se(n,γ)81Se und der Kernstruktur von 77Se, 78Se und 81Se mit Hilfe von (n,γ)-Reaktionen / Neutron Capture Mechanism in the Reaction 80Se(n,γ) 81Se and Nuclear Structure of 77Se, 78Se and 81Se, Studied In The (n,γ) -Reaction
Authors: Rabenstein D. , Vonach H. 
Published: February 2015

Abstract
Gamma radiation from the capture of neutrons in natural Se and in enriched 76Se and 80Se has been studied with different Ge (Li)-detectors, with a Ge(Li)-NaJ pair spectrometer and with a Ge (Li) -Ge (Li) two-paramater γ-γ coincidence system. These measurements resulted in a considerable improvement of the level schemes of 77Se, 78Se and 81Se. The 81Se and the 107Ag level schemes are compared, and the applicability of phonon-particle coupling to low-lying states of 81Se is discussed. In the case of 77Se, some properties may be possibly better described by the Nilsson model. It is rather clear, however, that both models can only be regarded as limited approximations and that more refined models are required for Se nuclei.
The well-known, unusually small isomeric cross section ratio of 81Se, and the weak population of p-single-quasiparticle states by primary transitions from the capture state 80Se + n, which shows up in our measurements, may be understood by assuming a capture state containing a doorway state with a simple collective excitation.
Investigation of Lithium Precipitates in Germanium Crystals by Anomalous X-Ray Transmission
Authors: Wenzl Helmut F. 
Published: February 2015

Abstract
The precipitation of lithium dissolved in germanium crystals and the re-solution of the precipitates during heating has been studied by means of anomalous transmission of x-rays. The effective absorption coefficient depends sensitively on the spacial distribution of lithium interstitials, and is enhanced enormously if pair correlations increase, as is the case during clustering. On the basis of Dederidis' theory and knowledge about the Geli phase diagram, the experiments provide relations between concentration and radius of the precipitates, distortion parameters, and average and local concentration of lithium interstitials.
Untersuchung der Wendelinstabilität an einem wandstabilisierten Wasserstoffbogen
Authors: Mentel Jürgen 
Published: February 2015

Abstract
The formation of a steady helical instability in a wall-stabilized hydrogen arc at low currents is investigated experimentally. To determine the onset-point of the instability theoretically the basic equations of electrodynamics and the balance of mass, momentum and energy are solved in the limiting case of vanishing growth-rate of the instability, taking into account the dissipative terms as well as the temperature dependence of the density. It turns out that the destabilizing J X B-forces, which try to deflect the arc by a convective heat-transfer, are balanced by the thermal stabilization of the tube-wall as well as by the unsym metrical energy-production in the curved arc. Onset-point and pitch of the helix result from the theory in full agreement with the measurements.
Kraftkonstanten der Siliciumtetrahalogenide und Schwingungsberechnungen an Chlorbromsilanen SiClnBr4–n
Authors: Höfler Friedrich 
Published: February 2015

Abstract
Ausgehend von den nach verschiedenen Verfahren erhaltenen Kraftfeldern von SiF4 und SiCl4 werden für SiBr4 und SiJ4 Kraftkonstantensätze angegeben. Zur Berechnung der Grundschwingungen von SiCl3Br, SiCl2Br2 und SiClBrs eignen sich Kraftkonstanten, die direkt oder nach geeigneter Mittelung bzw. Abstufung von SiCl4 und SiBr4 übertragen werden. Eine Neuaufnahm e des Raman- Spektrums von SiClBr3 ergibt, daß ν6 in Übereinstimmung mit der Berechnung bei 161 cm-1 liegt.
Berechnung der elektrostatischen Wechselwirkungsenergie für ein Kristallgitter zylindersymmetrischer Teilchen
Authors: Neckel A. , Kuzmany P. , Vinek G. 
Published: February 2015

Abstract
A method is presented for the calculation of the electrostatic interaction energy in a crystal lattice taking into account the real charge distribution of the particles. For this purpose the charge distribution of a particle is represented by a superposition of multipole moments. The crystal potential is expanded into amultipole expansion, the resulting lattice sums being evaluated according to Ewald's method. The present paper is restricted to the treatment of molecules or molecule-ions of cylindrical symmetry.
Berechnung der Gitterenergie der Alkalihydrogenfluoride KHF2, RbHF2 und CsHF2
Authors: Neckel A. , Kuzmany P. , Vinek G. 
Published: February 2015

Abstract
In the paper of Neckel , Kuzmany , and Vinek5 a procedure was proposed for the calculation of the electrostatic interaction energy of a crystal lattice provided the multipole moments of the particles are known. In the present paper a method for calculating multipole moments using LCAO-MO-wave functions is discussed. The multipole moments for the [FHF]--ion and the Madelung energy of KHF2 , RbHF2 and CsHF2 are evaluated. The results are com pared with calculations obtained by using a point charge model. For KHF2 , RbHF2 and CsHF2, the total lattice energies are evaluated.
The Conductance of the Alkali Halides I. Sodium Chloride in Sulfolane-water Mixtures, at 25 °C and 35 °C
Authors: Castagnolo M. , Jannelli L. , Petrella G. , Sacco A. 
Published: February 2015

Abstract The electrochemical behaviour of sodium chloride in water-sulfolane mixtures, at 25 °C and 35 °C, was investigated, the concentration of the salt ranging within (1÷7)·10-3 moles/liter and the dielectric constant (D) of the solvent mixtures within 78 and 44.
Analyzing the data by the Fuoss, Onsager and Skinner treatment, Λ0, aL, A , aA and Λ0 η values were obtained. At both temperatures, Λ0 is a smooth function of the solvent compositions; a re­markable association seems evident at D < 60 ; log A vs. 1/D plots are linear; the contact distances
of the ions are lower than in other isodielectric media.
Except for a limited region close to pure water, the Walden product Λ0 η is constant (1.20 at
25 °C and 1.19 at 35 °C) in the whole solvent composition range.
Schwingungs-und Kernresonanzspektren von Trijodsilan und gemischten Trihalogensilanen
Authors: Hengge E. , Hofler F. 
Published: February 2015

Abstract
Die aus den Raman-Spektren erhaltenen Grundschwingungen von HSiJ3 , HSiClJ2 (I), HSiCl2J (II), HSiBrJ2 (III) und HSiBr2J (IV) sowie von SiBr2J2 und SiBrJ3 werden mitgeteilt. Die Zuordnung erfolgt nach spektralen Übergängen und wird durch Kraftfelder gesichert. Die bisher unbekannten Mischhalogenide I - IV entstehen durch Äquilibrierung von HSiJ3 und HSiCl3 bzw. HSiJ3 und SiBr4; sie werden auch über ihre 1H-NMR-Parameter τ (SiH) und J (29SiH) charakterisiert.
On a Unified Theory of Twocentre Harmonic Oscillator Integrals I. The Onedimensional Oscillator
Authors: Wltschel W . 
Published: February 2015

Abstract
Twocentre harmonic oscillator overlap integrals, arbitrary transition integrals and collision energy etchange integrals for equal and different frequencies of the oscillators are contained in a generalized Franck-Condon-integral which is solved by operator methods in the second quantization representation.
Mischungswärmen und Verbindungsbildung in binären flüssigen Systemen
Authors: Becker F. , Kiefer M. 
Published: February 2015

Abstract
The enthalpies of mixing at 25° of diethyl ether, di-n-propyl ether, di-n-butyl ether, di-isopropyl ether, propylene oxide, tetrahydrofuran, and tetrahydropyran with chloroform are determined by an isothermal titration method. As a result, the functions HM-f(N CHCl3) are obtained with a step width of 0.025 of the mole fraction and a relative accuracy of 1 per cent or better. Evaluation of the heat of mixing data by means of equilibrium models ("ideal associated mixture") shows that the systems of aliphatic ethers with chloroform behave rather precisely as one-step equilibria of the type A + B = AB (A = ether; B = chloroform). In the systems of cyclic ethers with chloroform, a se­cond equilibrium step, AB + B = AB2 , must be considered, the importance of which decreases with increasing ring size of the ether. The equilibrium data calculated for the seven ether-diloroform systems are discussed.
Main Absorption Region of some Pure Normal Alcohols and of Mixtures of Butyl Alcohol with Non-Polar Solvents
Authors: Hanna F . F . , Hakim I. K . 
Published: February 2015

Abstract
The dielectric constant ε' and dielectric loss ε" are measured for pure n-butyl, n-amyl, n-octyl, n-dodecyl alcohols and for concentrated solutions of n-butyl alcohol in four non-polar solvents at three frequencies between 100 and 400 MHz at three temperatures between 20 and 60 °C. The effective dipole moment has been calculated for the concentrated solutions and the results obtained are discussed. The relaxation times of the concentrated solutions of n-butyl alcohol are in general higher than that of pure n-butyl alcohol (contrary to what was found before in case of n-decyl alcohol) but decreases with increasing dilution.
Thermodiffusion im kritischen Verdampfungsgebiet binärer Systeme
Authors: Haase R. , Borgmann H.-W. , Dücker K.-H. , Lee W.-P. 
Published: February 2015

Abstract
Es werden Messungen des Thermodiffusionsfaktors für das fluide System Methan + Propan beschrieben und diskutiert. Dabei liegt der Druck zwischen 40 und 75 bar, die mittlere Temperatur bei rund 73 °C, der mittlere Molenbruch des Methans zwischen 0,23 und 0,63. Das System befindet sich in der Nähe eines kritischen Verdampfungspunktes, und zwar teils im Gaszustand, teils im hyperkritischen Gebiet. Die Prüfung eines auf Plausibilitätsbetrachtungen beruhenden Ansatzes für den Thermodiffussionsfaktor bei fluiden Zweistoffsystemen (Haase 1950) führt zu einem qualitativ befriedigenden Bild. Insbesondere ist die Aussage, daß der Thermodiffusionsfaktor bei Annäherung an einen kritischen Punkt unendlich wird, mit den Messungen am vorliegenden System und auch an anderen binären fluiden Systemen verträglich.
Oxygen Isotope Ratios in the Crust of Iron Meteorites
Authors: Heinzinger K. , Iunge C. , Schidlowski M. 
Published: February 2015

Abstract
The separation factor, aM-0= (18O/16O) magnetite/' (18O/16O) atmospheric oxygen, between the magnetite crust of iron meteorites and atmospheric oxygen has been determined to be 0.9946 ± 0.0005. It is concluded that this fractionation of the oxygen isotopes is the consequence of an equilibrium isotope effect at high temperatures. It can be assumed that this is also valid for cosmic spherules, which are mainly ablation products of iron meteorites. As these spherules are found in sediments of different geological ages, their oxygen isotope ratio can give information on the development of atmospheric oxygen.
The difference of the oxygen isotope ratios between magnetite from the lithosphere and airborne magnetite can be used to distinguish between terrestrial and extraterrestrial material.
Relativistic Doppler Effect and Group Velocity in Homogeneous Nonlinear and Inhomogeneous Plasmas
Authors: Nicolis John S. , Athanassoula E. 
Published: February 2015

Abstract
We study the variations of the received frequencies (Complex Doppler effect) from a source moving uniformly in a homogeneous isotropic plasma and emitting a uniform EM plane wave with amplitude E0, as a function of ωe/Eo where ωe is the plasma frequency. The ratio of the velocity U of the source over the group velocity Ugr of the transmitted wave is then calculated from the slope of the Doppler curves.
When the plasma is inhomogeneous (one-dimensional stratification) the Doppler effect depends on the particular profile of the refractive index and its higher (even) derivatives with respect to the direction of stratification z. In this case the ratio U/Ugr=f(z) is given as the solution of a higher order differential equation with inhomogeneous part depending on the slope of the Doppler curve with respect to frequency. Typical cases involving symmetrical and transition profiles are examined. Harmonic generation in the plasma is not taken into account.
Einfluß von Quanteneffekten der Methylgruppenrotation auf die Kernrelaxation in Festkörpern
Authors: Haupt J. 
Published: February 2015

Abstract
By treating the hindered methyl group rotation in solids quantum-mechanically the proton spin lattice relaxation at low temperatures is calculated in first and second order. For low hindering barriers (smaller than 1 kcal/mole) significant differences from the usual relaxation theory are obtained. The inverse correlation time 1/τ0 is essentially given by the rate of non magnetic transitions between the zeroth and first torsional state; and as a consequence the apparent activation energy at low temperatures is given by the difference between these levels. For a given To the relaxation is by a factor ω0/Λ0 (Λ0 is the tunneling frequency) less effective than in the classical case. Good agreement between earlier measurements and this theory is obtained by considering at low efficiency factors also the magnetic interaction between the methylprotons and the surrounding protons. In this way the experimentally observed two relaxation maxima and the ω0-dependence can be explained too.
Stability to Localized Modes for a Class of Axisymmetric Magnetohydrodynamic Equilibria
Authors: Küppers G. , Tasso H. 
Published: February 2015

Abstract
Mercier’s criterion is computed numerically for an exact class of axisymmetric MHD equilibria having possibly elliptical cross sections and a flat current profile. The main result is that the toroidal current density and the plasma beta can be increased by one order of magnitude if a) the eccentricity of the magnetic surfaces, b) the poloidal current, and c) the aspect ratio are adequately chosen, and if the ellipses are vertical.
Untersuchung der Ion-Molekül-Reaktionen des Thiothionylfluorids mit Hilfe der Ionen-Cyclotronresonanz-Spektrometrie / Investigation Of Ion-Molecule Reactions Of Thiothionylfluorid By Ion Cyclotron Resonance Spectrometry
Authors: Wanczek K.-P. , Lebert K.-H. , Hartmann H. 
Published: February 2015

Abstract
The ion-molecule reactions of thiothionylfluoride have been studied by ion cyclotron resonance spectrometry. The major secondary ions are S2F3
+ , S3F+ , and S3F2
+. In a consecutive reaction of S3F2
+ the tertiary ion S4F2
+ is formed. The rate constant of the IMR with the greatest yield
S2F2
+
+ SSF2 → S3F2
+
+ SF

was estimated to
k = 2 · 10-9 cm 3 molecule -1 sec -1 .
The results were compared with the mass spectrum of thiothionylfluoride. They permit conclusions on chemical reactions of lower sulphurfluorides.
Bildung von van der Waals-Komplexen organischer Moleküle
Authors: Knof Hans , Hausen Volker , Krafft Dieter 
Published: February 2015

Abstract
An electron attachment ion source was modified in order to be used for quantitative measurement of pure organic substances at pressures up to 1.5 ·10-3 Torr in the space around the ion source. The ion intensity was determined by counting the electron pulses produced by single ions in the secondary electron multiplier. This resulted in higher sensitivities. The measurements of different organic compounds showed that molecular polymers are held together primarily by hydro-gen bonding and by dipole interaction. No molecular polymers could be identified in nonpolar substances. The pressure dependence of the ion intensities indicates that the molecular polymers originate from the gas phase of the reservoir. During the ionization process the hydroxide loses its hydrogen atom as was shown with deuterated samples.
Atom-gJ -Faktoren und Lebensdauern der z3 F-Terme im Titan I-Spektrum / Atomic gJ-Values and, Lifetimes of the z 3F-States in the Titanium I-Spectrum
Authors: Hese A. 
Published: February 2015

Abstract
Stimulated by a complete theoretical investigation of the odd configurations in the Titanium Ispectrum the optical double resonance method has been applied to measure the atomic gJ-values and lifetimes of the excited 3d2 4s 4p z 3F2,3,4-states. Using a Titanium atomic beam in natural isotope composition the following values were deduced from the position and the width of the radiofrequency transition signals:

.
The experimental results shall be discussed with respect to other experimental and theoretical values.
A Note on the Integral Equation Formulation of Dynamical Theory
Authors: Gjønnes Jon 
Published: February 2015

Abstract
The coupled integral equations for dynamical scattering are developed from the general integral equation. The results are given in the forward scattering approximation. Extension to bade scattering is briefly mentioned. Expressions for distorted crystals are derived both in the column approximation and beyond. The formulation is suggested to be very useful as a basis for perturbation methods.
A Theoretical Analysis of the Weak-beam Method of Electron Microscopy
Authors: Cockayne D.J.H. 
Published: February 2015

Abstract
The geometry of lattice defects can be studied in detail using the weak-beam method 1 of high resolution electron microscopy. In this paper the theoretical basis of the method is discussed, and the experimental conditions which are necessary if particular methods of image interpretation are to be used are considered.
Affine Deformation von linearem Polyäthylen / Affine Deformation of Linear Polyethylene
Authors: Hosemann R , Loboda-Čačković J , Čačković H 
Published: February 2015

Abstract
Linear polyethylene, as an example of high polymers, can have a shape in the molten state and has a "memory" to rebuild the shape it had before having been hot or cold stretched. It is proved that these processes are three dimensional affine deformations of a colloidal superstructure. This superstructure can be characterized as the centres of the crystalline domains in the melt crystallized material, which are interconnected by "non-individual" molecules. It forms the holder of the memory which shows a rubberlike elasticity. The maximum draw ratio up to which the drawing remains a pure affine deformation lies for Lupolen 6001 H (BASF) at approximately 10. The processes within the crystalline domains are very complicated and will not be treated here. It turns out that every single crystalline domain of the melt crystallized material is transformed by stretching into about 20 smaller crystalline domaians which lie together like a string of pearls and form parts of the so-called ultrafibrils of the stretched material. Heated above the melting point, the domains regain their former shape, but with disordered inner structure.
Part of these result were already deal whit during the spring meeting of the Fachausschuß ″Phyisk der Hochpolymeren″ of the German Physical Society, 9-13 March 1971 in Berlin.