bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decomposition of Viscosity Tensors for Gyrotropic Media
Authors: Sturhann Ursula , Suchy Kurt 
Published: February 2015

Abstract
For a medium whose anisotropy is caused by a physical quantity expressed by an axial vector, e. g. an ambient magnetic field, the viscosity tensor has 8 independent components and is consequently decomposed in 8 terms. One term, multiplied with the bulk viscosity, connects the traces of the viscous pressure tensor and the velocity gradient, while traces and tracefree parts of these two tensors are coupled by two other terms, whose coefficients are required to be equal by Onsager's symmetry relations. The remaining 5 terms are represented by generalized Hess-Waldmann projectors. The corresponding 5 viscosity coefficients are related to those introduced by Braginskii, de Groot-Mazur, and Hess-Waldmann.
Lineare Welleneinkopplung in ein Plasma erhöhter Elektronen- Temperatur bei der unteren Hybridresonanz / Linear Wave Coupling to a Plasma of Enhanced Electron Temperature at the Lower Hybrid Resonance
Authors: Glomski G. , Heinrich B. , Schlüter H. 
Published: February 2015

Abstract
Linear Wave Coupling to a Plasma of Enhanced Electron Temperature at the Lower Hybrid Resonance Radio frequency waves in the range of the lower hybrid resonance are coupled to a plasma of enhanced electron temperature (≈ 106 K) and reduced collision frequency (≈ 7 · 105 s-1). The experiment demonstrates the persistance of resonance behavior even under this conditions. Radial eigenmodes are dominant, but exhibit - as compared to linear theoretical models - additional damping with an effective collision frequency in the order of 3 · 107
s-1. For the conditions considered this effect is attributable to Landau damping.
Einfluß von Spiegelanordnungen bei der unteren Hybridresonanz / The Influence of Mirror Configurations Near the Lower Hybrid Resonance
Authors: Glomski G. , Heinrich B. , Schlüter H. 
Published: February 2015

Abstract
The Influence of Mirror Configurations Near the Lower Hybrid. Resonance Hydrogen plasmas in magnetic mirror configurations are generated by microwaves and inductively coupled to a weak rf-source. In contrast to previous investigations the rf-frequency is varied; resonant behaviour near the lower hybrid frequency is found, attributable to radial eigenmodes. The influence of various mirror ratios and consequently varying axial density gradients on the position of the modes is studied. Shifts of the coupling coil are found to be of minor importance, since the resonant behaviour is dominated by oscillations of the whole plasma body.
Nichtlineare Welleneinkopplung in ein Plasma erhöhter Elektronentemperatur / Nonlinear Wave Coupling to a Plasma of Enhanced Electron Temperature
Authors: Glomski G. , Heinrich B. , Schlüter H. 
Published: February 2015

Abstract
Nonlinear Wave Coupling to a Plasma of Enhanced Electron Temperature In continuation of former investigations radio waves of different amplitude in the domain of lower hybrid resonance were coupled to a plasma of enhanced electron temperature. Under linear conditions no dependence of resonance behaviour on the wave amplitude was observed. Exceeding a treshhold maximum of absorption and electron density decreased significantly; both observations may be explained by onset of nonlinear and parametric effects. Increasing the amplitude the discharge only could be maintained by increasing the neutral gas pressure. In the power range of 15 to 20 kW electron density grew rapidly at resonance.
Symmetry Coordinates and Tentative Force Field Analysis of a PMo12O40 Model with the Keggin Structure
Authors: Lyhamn Lennart , Cyvin S. J. , Cyvin B. N. , Brunvoll J. 
Published: February 2015

Abstract
A complete vibrational analysis is performed for the 53 atomic PMo12O40 model of Td symmetry. The symmetry coordinates are classified into those of (a) ligand vibrations, (b) framework-ligand couplings, (c) framework vibrations, and (d) interligand vibrations. Simple valence force fields are estimated, and the influence of inclusion of redundancies on the calculated frequencies and symmetry force constants is investigated. Comments are made on calculated symmetry force constant values up to 345 mdyne/Å. Vibrational frequencies are calculated for the Mo3O7 and Mo3O13 units and for the PMo12O40
3- complex ion. For the latter compound the calculated values are compared with experimental data from infrared and Raman spectra.
Nachweis einer antiparallelen Spinkopplung in paramagnetischem Manganoxid / Proof of Antiparallel Spin-Coupling in Paramagnetic Manganese Oxid
Authors: Dräger K. , Kratz G. 
Published: February 2015

Abstract
For temperatures above the Néel-point it is shown that there are severe deviations from pure paramagnetism in the ESR-behaviour of stoechiometric MnO. The experimental results in the temperature range between 130 K and 480 K are interpreted by a model of local order. The excitation energy necessary to decouple the antiferromagnetic bonding is computed to be about ΔE= 250 ± 15 cm-1 . For a temperature of T=TN +10 we derive that according to this theory 73% of all spins in MnO still remain in antiparallel order.
Further calculations show that the bonding is compatible with an isotropic exchange interaction of next nearest neighbours having a coupling constant of J2 = 3.42 K. Finally, an interesting aspect is discussed connecting the formation of antiferromagnetic clusters and the absorption behaviour of MnO in the far infrared.
Ultrasound Absorption in Trifluoroacetic Acid and its Equimolar Mixture with Acetic Acid
Authors: Mang H. , Kohler Friedrich 
Published: February 2015

Abstract
Ultrasound absorption has been measured in pure trifluoroacetic acid and its approximately equimolar mixture with acetic acid (51.5 mole% of acetic acid) at 20, 30, 40, and 50 °C and atmospheric pressure over the frequency range 3 - 57 MHz. The absorption curve of trifluoroacetic acid could be flitted by a single relaxation step (relaxation frequency 3.5 - 11 MHz, low frequency absorption about one tenth of that of acetic acid), whereas the equimolar mixture followed a two step relaxation curve (lower relaxation frequency 1.5 - 3 MHz, absorption correspondingly higher than in pure trifluoroacetic acid, higher relaxation frequency 12.5 - 39 MHz, absorption about 3% of the low frequency absorption).
Gas Supersaturation Thresholds for Spontaneous Cavitation in Water with Gas Equilibration Pressures up to 570 atm1
Authors: Gerth Wayne A. , Hemmingsen Edvard A. 
Published: February 2015

Abstract
Supersaturations for the onset of cavitation in water were determined for various gases. At ambient pressure, the threshold supersaturations (in atm) required for profuse cavitation to initiate both in bulk water and at the glass-water interface were CH4, 120; Ar, 160; N2, 190; He, 360. Exposure of the water and its containing surfaces to hydrostatic pressures up to 1100 atm prior to equilibration with gas had no detectable effect on these threshold values. This indicates that preformed gas nuclei are not significantly involved. Cavitation at the glass-water interface was investigated for CH4, Ar and N2 saturations up to 570 atm. For 320 atm saturations, the threshold super-saturation was about one-half that for decompression directly to ambient pressure, and for 550 atm it was about one-third. These results indicate that the dissolved gas concentration is a critical factor limiting the spontaneous nucleation of bubbles in gas supersaturated liquids.
Fourier Transform NMR Studies of 95Mo and 97Mo
Authors: Kautt W. D. , Krüger H. , Lutz O. , Maier H. , Nolle A. 
Published: February 2015

95Mo and 97Mo Fourier transform NMR studies of several alkali molybdate solutions in H2O and D2O are reported. The Larmor frequency of the molybdenum nuclides is remarkably dependent on the solute and the solvent.
In potassium molybdate the chemical shifts of 39K were observed. The ratio of the Larmor frequencies of 95Mo and 39K was measured with high accuracy in a 2.6 molal solution of K2MoO4 in H2O. From this value a nuclear magnetic moment of 95Mo and 97Mo in the molybdate ion was derived using the concentration dependencies of the Larmor frequencies of 39K and 95Mo and the ratio of the Larmor frequencies of 97Mo and 95Mo.
In solid Ag2MoO4 and metallic molybdenum the 95Mo and 97Mo NMR signals were detected; line widths and shifts are given.
Adiabatische Korrektur der Born-Oppenheimer-Näherung beim GeS und GeSe / Adiabatic Correction of the Born-Oppenheimer Approximation for GeS and GeSe
Authors: Stieda W. U. , Tiemann E. , Törring T. , Hoeft J. 
Published: February 2015

Abstract
The rotational spectra of GeS and GeSe were measured in the frequency range of 66 GHz to 110 GHz with high precision. The breakdown of the Born-Oppenheimer approximation was observed for the rotational constant yol. With the known molecular 37-factor and the electric dipole moment the adiabatic part of the Born-Oppenheimer correction can be extracted from the primary observa-tion on y01. The adiabatic correction is very similar in both molecules but differs from the results in the earlier measurements on PbS.
8Li Emission in 1.8 GeV/c K– -Meson Interactions in Nuclear Emulsion
Authors: Mandal P. , Bhattacharya D. K. , Saha M. , Sen P. K. , Bhattacharya P. C. , Ghosal S. N. 
Published: February 2015

Abstract
Out of about 16,000 stars found by an area scan of 1.8 GeV/c K--meson interactions with emul­sion nuclei, 120 'hammer tracks' have been collected. The corrected production rate is (1.30 ± 0.12)^. The forward to backward ratio indicates isotropic emission of 8Li fragments. The emission of short recoils at the primary vertex shows a definite correlation with the 8Li fragments.
Nonlinear Oscillations in Chemical Networks as Symmetries of Transformation Groups
Authors: Busse H. G. , Havsteen B. 
Published: February 2015

Abstract
The description of phenomena created by nonlinear oscillators with the aid of transformation groups has been attempted. Such a treatment of the chemical model of Dreitlein and Smoes was met with success. The mathematical approach is based on an application of the canonical form theorem for one-parameter groups. Conditions for the occurence of limit cycles have been derived.
Hypersonic Velocity, Absorption and Relaxation in Molten CSNO3
Authors: Knape H. E. Gunilla , Torell Lena M. 
Published: February 2015

Abstract
Brillouin spectra of molten CSNO3 were investigated for scattering angles between 40 and 140° and in a temperature interval of 420-520 °C. An Ar+ singlemode laser was used for excitation and the total instrumental width was ~265 MHz. The measured frequency shifts and linewidths of the Brillouin components were used to determine velocities and attenuations of thermal sound waves in the frequency range 2.3-7.0 GHz. A dispersion of 4-5% was found between the present hyper­ sonic velocities and reported ultrasonic velocities. A considerable decrease in attenuation with frequency was observed in the investigated frequency range, with the value at high frequency ap­ proaching the classical attenuation. The results are in good agreement with Mountain's theory of a single relaxation time. The relaxation time of the bulk viscosity coefficient was calculated to 1.2×10-10
S.
Pseudo-exact Force Constants for Tetramethyls of Group IVA Metals and Molecular Force Fields for Some Tetrahedral Molecules or Ions
Authors: Dublish A. K. , Srivastava B. B. , Sharma D. K. , Verma U. P. , Pandey A. N. 
Published: February 2015

Abstract
Recently reported Coriolis constants of tetrahedral tetramethyls of group IVA metals from the vapour phase IR spectra have been used to determine the pseudo-exact force constants with the aid of the point mass model. The symmetrized force constants for tetramethyls of group IVA and some tetrahedral molecules and ions have also been computed following thhe L-F approximation method. The results are compared with exact or pseudo-exact force constants and with those force constants obtained from different approximation methods. The validity of the method has been tested.
Untersuchung von Level-Crossing-Signalen an schnellen He-Atomen in inhomogenen Magnetfeldern / Investigation of Level-crossing Signals on High-velocity He-atoms in Inhomogeneous Magnetic Fields
Authors: Oppen G. v. , Perschmann W.-D. 
Published: February 2015

Abstract
In level-crossing experiments on high-velocity atoms, the shape of the observed signals depends sensitively on inhomogeneities of the applied magnetic field. With regard to the interpretation of such signals, we investigated the magnetic-field dependence of He I-fluorescence light excited by He-ion-He-atom collisions. Due to the inhomogeneity of the applied magnetic field, the observed level-crossing signals have a distorted shape with an oscillating structure in the wings. Taking into account the motion of the excited atoms, the shape of the signals will be explained.
Delayed Emission from Green Algae “Chlorella pyrenoidosa” at Various Temperatures
Authors: Drissler F. , Hägele W. , Schmid D. , Wolf H. C. 
Published: February 2015

Abstract
Comparative studies of prompt and delayed emission from whole cells of Chlorella pyrenoidosa are presented for various temperatures between 4.2 and 300 K. Prompt emission was excited with continuous light (wavelengths between 420 and 670 nm). Light pulses (duration 6.9 msec) have been used to excite delayed emission. Their wavelength had to be shorter than 600 nm for investigations at 77 K.
A linear dependence of the delayed emission intensity on the excitation intensity at low temperatures (4.2 and 77 K) favours a one-quantum-mechanism to be responsible for delayed light production.
The response of the total intensities on temperature shows a similar behaviour for both types of emission up to 200 K. Above 200 K they behave quite differently.
A Covariant Semi-Classical Theory of the Radiating Electron
Authors: Sorg M. 
Published: February 2015

Abstract
A new semi-classical equation of motion is suggested for the radiating electron. The characteristic length of the new theory is the Compton wavelength λc(= ħ/2 m c) instead of the classical electron radius

which is used in all purely classical theories of the radiating electron. However, the lowest order approximation of the radiation reaction contains only the classical radius rc.
The Photoelectron Spectra of Cyclopropyl Ketones
Authors: Al-Khafaji Jabria A. , Shanshal Muthana 
Published: February 2015

Abstract
The photoelectron spectra of 1-and 2-methyl-cyclopropyl ketones are reported. It is found that the shifts in the MO energies of ⊿ext.as. and ⊿ext.s. MO's of the three membered ring are parallel to the predictions based on the perturba­tion of the Walsh orbitals and on the MINDO/2 calculations.
Improved Rotational Constants and Dipole Moment and a Nuclear Quadrupole Coupling Analysis of 2-Cyanothiophene and Dipole Moment of 2-Cyanofurane
Authors: Wiese J. , Engelbrecht L. , Dreizler H. 
Published: February 2015

Results of a microwave investigation of the molecules 2-Cyanothiophene and 2-Cyanofurane are reported. The microwave spectrum of 2-Cyanothiophene was examined in the frequency range of 13 -40 GHz mainly to get a more accurate rotational constant A from the assignment of μb-btransitions. From the resolved hyperfine structure due to nuclear quadrupole coupling of the 14N-nucleus the quadrupole coupling constant X+=Xbb + Xcc was determined for 2-Cyanothiophene. No information for X- was available from the measured transitions.
From Stark effect studies the dipole moments were determined for both molecules. The nuclear quadrupole coupling as a perturbation of the second order Stark effect was included in the Stark effect analysis
Finite Size of the Electron and Runaway Solutions
Authors: Petzold J. , Heudorfer W. , Sorg M. 
Published: February 2015

Abstract
The problem of runaway solutions is studied within the framework of a non-local equation of motion for the classically radiating electron. It is found that the force-free electron oscillates down to a constant velocity under emission of radiation, if certain restrictions on the initial conditions are imposed. Causality violation is not present in this model, but penetrates into the theory as consequence of a false perturbation expansion leading to the notorious Lorentz-Dirac equation of motion.
Finite Perturbation Studies of Magnetic Susceptibility and Shielding with GIAO
Authors: Žaucer Matjaž , Pumpernik Danilo , Hladnik Milan , Ažman Andrej 
Published: February 2015

Abstract
The magnetic susceptibility tensor and proton and fluorine magnetic shielding tensors are cal­ culated for F2 and (FHF)- using an ab initio finite perturbation method with gauge-invariant atomic orbitals (GIAO). The discussion of the basis set deficiency shows that the calculated values for the susceptibilities are reliable. Simple additivity (Pascal rule) for the susceptibility is con­ firmed.
Analogie zwischen elastischem und plastischem Potential anisotroper Stoffe / Analogy between the Elastic and Plastic Potential of Anisotropic Materials
Authors: Betten Josef 
Published: February 2015

Abstract
The elastic strain energy of distortion and its complementary energy of incompressible materials can be represented formally by linear combinations of partial plastic potentials of the forms Fρ = (1/ρ)Dijkl...qr σ′ij′σkl ... σqr. Likewise, it is possible to describe the elastic strain energy of deformation and its complementary energy of compressible materials formally by plastic potentials of the forms Fρ = (1/ρ)Dijkl...qr σijσkl ... σqr. In a linear theory, for example, we have F2= ½Dijkl σ′ij σ′kl for incompressible materials and F2 =½Dijkl σ′ij σ′kl for compressible materials.
It is necessary to notice, that only a formal analogy exsists between the elastic and plastic po­tential, because the physical interpretation of these potentials is quite different.
Evidence of Tilt of the Methyl Top Axis in the r,-structure of Dimethyl Selenide
Authors: Pandey G. K. , Dreizler H. 
Published: February 2015

Abstract
The complete rs-structure of dimethyl selenide has been determined by using suitably chosen changes in principal moments of inertia of a number of isotopic species. The tilt of the methyl top axis with respect to the C -Se bond, as determined by the analysis of the internal rotation fine structure of the rotational transitions is also evidenced in the rs-structure. The center of mass condition has been used.
Molecular Dynamics Simulation of Solid α-Nitrogen
Authors: Romano S. 
Published: February 2015

Abstract
The present paper reports on Molecular Dynamics simulation of solid a-Nitrogen, using an atom-atom Lennard-Jones potential together with a point-quadrupolar interaction. Calculations were car­ ried out at five temperatures up to 45 K; the addition of the quadrupolar term appears to improve the agreement with experiment, although this still remains rather unsatisfactory.
Thermodynamic Excess Functions for the Liquid System W ater + Acetic Acid from Calorimetric Data
Authors: Haase R. , Pehlke M. 
Published: February 2015

Abstract
For the liquid system water + acetic acid, we give the results of new calorimetric measurements regarding the molar excess enthalpy H̅E for 25 °C, 30 °C, 35 °C, 40 °C, 55 °C, and 70 °C, covering nearly the entire range of com­ positions. The experimental data show that H̅E is positive for all compositions and temperatures except in the region of low acid concentrations at temperatures below 55 °C where the process of mixing the pure liquid components is exothermic (H̅E<0). Using values of the molar excess Gibbs function G̅E (always positive) derived from earlier data on vapour-liquid equilibria, we compute the molar ex­cess entropy S̅E which is always negative. The “symmetryrule” concerning the composition dependence of G̅E (as compared to that of H̅E and S̅E) has again been confirmed. The composition dependence of S̅E is similar to that of the molar excess volume.
Open-ended Plastic Capillary Method for Diffusion Experiments with β-active Tracers
Authors: Passiniemi P. , Liukkonen S. , Rastas J. 
Published: February 2015

Abstract
An open-ended capillary method, where the capillary is drilled directly into a plastic scintillator, is described. The method is tested with 38Cl in 0.1 M and 0.5 M NaCl solutions.
Low Frequency Dispersion of a Molecular Crystal
Authors: Hinopoulos B. , Sakellaridis P. U. 
Published: February 2015

Abstract
The dielectric behaviour of solid 1,4-Butandiol has been studied. A region of low frequency dispersion has been ob­ served. In a crystalline sample treated to have more lattice faults, the losses were increased. The effect is attributed to a dielectric relaxation process existing in connection with the lattice defects.
I Investigation of Particle Velocities in a ‘Critical Velocity’ Rotating Plasma
Authors: Himmel G. , Möbius E. , Piel A. 
Published: February 2015

Abstract
The velocities of helium ions and neutrals are derived from Doppler shifted spectral lines He II 4686 Å and He I 5876 Å respectively. The ion velocity proves to be in accordance with the speed of rotating spokes which are usually observed in the build-up phase of rotating plasmas. It is demonstrated that the spoke velocity represents the plasma mass motion. Braking of plasma motion and acceleration of the neutrals to a value near Alfvén's critical velocity occurs within 10 μs.
Photodetachment bei einigen negativen Molekülionen: P2
–, As2
-, CH2
-, CH3
-, S3
- / Photodetachment of Some Molecular Negative Ions: P2
-, As2
-, CH2
-, CH3
-, S3
-
Authors: Feldmann D. , Rackwitz R. , Kaiser H. J. , Heinicke E. 
Published: February 2015

Abstract
The cross sections have been measured between 0.5 eV and 3 eV photon energy.
Dielectric Dispersion Studies of Some Intramolecular Hydrogen Bonded Molecules at Microwave Frequencies
Authors: Purohit H. D. , Kumar S. , Vyas A. D. 
Published: February 2015

Abstract
The permittivity and dielectric loss of acetyl acetone, benzoyl acetone and dibenzoyl methane have been measured at four microwave frequencies viz., 30.20, 24.50, 18.26, and 9.83 GHz and also at 1 MHz and optical frequency at 35 °C. The permittivity and dielectric loss at different frequen­ cies have been plotted against concentration (wt. fraction). The slopes of these straight lines have been used for the complex plane plots (a″ vs. a′). The complex plane plots for these compounds are Cole-Cole arcs. The dielectric relaxation time (τ0) and distribution parameter (α) have been calculated from these plots. Data have been analysed in terms of two relaxation processes i. e., cor­ responding to overall rotation and group rotation. The dipole moments of these molecules are reported.
On the Thermal Behaviour of Long-Chain Lithium and Sodium n.Alkanoates
Authors: Ferloni P. , Zangen M. , Franzosini P. 
Published: February 2015

Abstract
The phase relationships in Li and Na n.alkanoates from octanoate to dodecanoate were investigated by means of DSC analysis. Clearing (when present), fusion, and solid state transition (when possible) temperatures and enthalpies were measured. The collected results are discussed in comparison with literature data, mostly obtained by different techniques.