bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resonanzverschiebungen in HF-Entladungen bei axialem Magnetfeld/Resonance Shifts in High Frequency Discharges in Axial Magnetic Field Configurations
Authors: Lammers B. , Oberlack U. , Schlüter H. 
Published: February 2015

Abstract
The pressure dependence of the lower hybrid resonance is investigated in a hydrogen plasma generated by a high frequency discharge. Appreciable shifts of the absorption peak with the neutral gas pressure are observed only in a mirror like magnetic field configuration. The measurements show that this shift cannot be explained by a change of the ion composition of the plasma, but must be attributed to two other mechanisms: The composition of the spectrum of the kn-components is influenced by the axial electron density profile so that at low pressure the higher modes of the spectrum are dominant.With higher pressure the formation of radial modes is favoured which leads to an additional apparent shift of the resonance.
Emittanz-Diagramme und Bildfehler von Elektronenkanonen
Authors: Lauer Rolf 
Published: February 2015

Abstract
The aberration coefficients of electron guns are determined from experimental shadow curves. For this purpose the curves are mathematically described by parametric equations using the ray inclination at the cathode as a parameter. Since the shape of the shadow curves depends strongly on the grid potential, different methods are required to adapt the calculated curves to the measured curves. Using the coefficients of the mathematical representation together with measured values for the magnification between cross-over and cathode, spherical and angular aberration are calculated with an accuracy of about 20%.
An I.R. Spectroscopic Study of the Conformational Equilibrium in 2-Acetylfuran
Authors: Paliani Giulio , Cataliotti Rosario , Poletti Antonio 
Published: February 2015

Abstract
The conformational cis/trans equilibrium of 2-Acetylfuran has been studied by i.r. spectroscopy, in various physical states. This equilibrium is strongly influenced by the dielectric constant of the medium. The isomeric energy difference is very small as revealed by the insensitivity of the equilibrium position to temperature changes.
Rotation -Torsion -Vibration Interaction in the Rotational Spectra of Isotopic Species of Ethyl Cyanide
Authors: Heise H. M. , Mäder H. , Dreizler H. 
Published: February 2015

Abstract
The measurements of the ground state rotational spectra of CH3CH2C15N and CH3CD2CN were extended to calculate the centrifugal distortion coefficients DJ , DJK and DK. The rotation-torsion-vibration interaction for these molecules including the normal species CH3CH2CN was studied in the rotational spectra of the first excited state of the methyl torsion and the CCN-in plane deformation. With respect to previous work a more detailed check of a model with five degrees of freedom comprising the overall rotation and the two lowest vibrations was possible. Potential parameters were fitted simultaneously to the splittings of the rotational transitions in the two lowest excited vibrational states of the three isotopic molecules. The coefficients V3 and V6 of the Fourier expansion of the hindering potential for the torsion and an interaction constant V'3c for the torsion and the CCN-in plane deformation were determined. Using these results it was possible to reproduce the frequencies of the torsional and CCN vibrations. With less success the torsional overtones could also be calculated.
Microwave Zeeman Spectrum, Electric Dipole Moment and Nuclear Quadrupole Tensor of Methyl Hypochlorite and d3 -Methyl Hypochlorite
Authors: Suzuki M. , Guarnieri A. 
Published: February 2015

Abstract
The microwave-Zeeman spectra of CH3O35Cl and CD3O35Cl have been investigated with magnetic fields up to 25 kG. In addition to the Zeeman parameters, the electric dipole moment and the chlorine nuclear quadrupole tensor have been determined.
Gleichgewichtseigenschaften von Ionenaustauschermembranen / Equilibrium Properties of Ion Exchange Membranes
Authors: Stormberg H.-P. 
Published: February 2015

Abstract
An electrolyte system in equilibrium is considered. The membrane acts on the ions by its electrostatic potential. Using a perturbation approximation in generalized Nernst Planck equations the densities are calculated for various electrolyte systems and various dielectric constants of the membrane.
Der Intensitätsverlauf im reinen Rotations-Raman-Spektrum von CO2 und N2O unter Berücksichtigung des 0110-Niveaus / Intensity Distribution in Pure Rotational Raman Spectra of CO2 and N2O Taking into Account Contributions from the 0110 State
Authors: Altmann K. , Klöckner W. , Strey G. 
Published: February 2015

Abstract
The pure rotational Raman spectra of carbon dioxide and nitrous oxide have been recorded with argon laser excitation and a resolution of about 0.2 cm-1. As was found previously for acetylene, also for these molecules R-branch transitions in the excited II-states could be resolved clearly up to J=9. The relative intensity distribution has been analyzed quantitatively according to formulae derived previously. It turns out that the experimental intensity distribution is well reproduced by taking into account only the

component of the anisotropic part of the polarizability tensor. Higher order contributions arising from the components

could not be detected.
Thermoreflectance in Ammonium Halides
Authors: Rieflin E. , Stühmer G. , Schwab E. 
Published: February 2015

Abstract
Thermoreflectance spectra of NH4I at 240 K, NH4Br at 93 K and NH4C1 at 160 K are measured. By a Kramers-Kronig analysis the differential optical dielectric constants are calculated to deter-mine band energies and their differential temperature behaviour. The spectra are compared with the excitonic spectra of the alkali halides, and the bands in NH4I are tentatively interpreted by analogy.
Electrochemical Transient Investigations of the Diffusion and Concentration of Electrons in Yttria Stabilized Zirconia-Solid Electrolytes
Authors: Weppner W. 
Published: February 2015

Abstract
The voltage relaxation of galvanic cells with zirconia electrolytes polarized between an inert silver electrode and an Fe + FeO electrode has been analyzed to obtain the diffusion coefficient of the electronic minority charge carriers in the temperature range between 700 and 900 °C. The method has been examined by using different thicknesses of the sample. At 800 °C the diffusion coefficient of the electrons is 1.4 × 10-3 cm2 /sec, i.e., about two orders of magnitude higher than that for the holes, 4.5 × 10-6 cm2/sec. The activation energy 0.55 eV is obtained for the electrons, compared to 1.4 eV for the holes. From conductivity data, the concentrations of electrons and holes at 800 °C and 1 atm oxygen partial pressure are calculated to be 1 × 109 and 4 × 1017 cm-3, respectively. The electronic band gap is evaluated to be 4.1 eV.
The Molecular Structures of HNC and HCN Derived from the Eight Stable Isotopic Species
Authors: Pearson E. F. , Creswell R. A. , Winnewisser M. , Winnewisser G. 
Published: February 2015

Abstract
Ground vibrational state rotational transitions have been measured for the following isotopic species of HNC: H15NC, H15N13C, DN13C, D15NC and D15N13C. Similar transitions have also been measured for H13C15N and D13C15N. These measurements complete the set of rotational constants for the eight stable isotopic species of the two molecules. Molecular structures are calculated from these data in several ways and are compared with the results of recent ab initio calculations.
Acetyl Cyanide II. Rotation–Torsion–Vibration Interaction in the Rotational Spectrum
Authors: Scappini F. , Mäder H. , Dreizler H. 
Published: February 2015

Abstract
The rotation-torsion-vibration interaction in acetyl cyanide, CH3COCN, has been studied in the rotational spectra of the first excited state of the methyl torsion and of the CCN-in-plane bending. A model with two internal degrees of freedom has been used to account for the A-E rotational splittings in the ground state and in the two excited states simultaneously. The constants in the Fourier expansion of the potential hindering the methyl torsion are determined. The results are compared with those obtained in a previous work from the A-E rotational splittings of the ground state only, using a model with one degree of freedom. Group theoretical considerations are made upon the Hamiltonian used in the present analysis.
Radialverteilung der Nachleuchte-Lichtintensität im Stickstoff / Radial Distribution of the Light-intensity in Nitrogen Afterglow
Authors: Kocian P. 
Published: February 2015

Abstract
Radial Distribution of the Light-intensity in Nitrogen Afterglow The radial distribution of the first positive band system in nitrogen afterglow in dependence on the discharge current and on the pressure has been investigated. The measurements were made in the pressure range 0.06 torr-6 torr. It has been found that the radial profile of the intensity fol-lows approximately the square of the J0 Bessel function.
Ionen-und Molekülbeweglichkeiten in einfachen binären Salzschmelzen / Ionic and Molecular Mobilities in Simple Binary Molten Salt Mixtures
Authors: Richter Joachim 
Published: February 2015

Abstract
For additive binary molten salt mixtures the ionic mobilities, the interdiffusion mobility and the self diffusion mobilities are defined. Values of these mobilities are given for the system NaNO3+AgNO3 at 290 °C in dependence of the composition.
Reciprocity and Boundary Conditions for Transport-Relaxation Equations
Authors: Waldmann L. 
Published: February 2015

Abstract
Recently a reciprocity theorem has been derived from the transport-relaxation equations for a simple system, consisting of one medium (Ref.1). With a composite system, consisting of two immiscible media in contact, a plausible generalized reciprocity scheme, here called universal reciprocity postulate, is suggested now. It leads to an equivalent reciprocity requirement at the inter-face between both media and thus decisively restricts - in form of provable Onsager relations - the possible constitutive laws connecting the thermodynamical forces and fluxes at the interface. For the formulation of these ideas, some mathematical tools are developed in advance. Finally, heat conduction is treated, as the most simple example, first in the direct way, then according to the more sophisticated mathematical tools.
Solitary Filaments of Coupled Electromagnetic Wave and Finite Amplitude Ion Fluctuations
Authors: Shukla P. K. , Yu M. Y. , Tagare S. G. 
Published: February 2015

Abstract
We show analytically that the nonlinear coupling of a large amplitude electromagnetic wave with finite amplitude ion fluctuations leads to filamentation. The latter consists of striations of the electromagnetic radiation trapped in depressions of the plasma density. The filamentation is found to be either standing or moving normal to the direction of the incoming radiation. Criteria for the existence of localized filaments are obtained. Small amplitude results are discussed.
Poisson's Ratio for Central-Force Polycrystals
Authors: Ledbetter H. M. 
Published: February 2015

Abstract
The Poisson ratio υ of a polycrystalline aggregate was calculated for both the face-centered cubic and the body-centered cubic cases. A general two-body central-force interatomatic potential was used. Deviations of υ from 0.25 were verified. A lower value of υ is predicted for the f.c.c. case than for the b.c.c. case. Observed values of υ for twenty-three cubic elements are discussed in terms of the predicted values. Effects of including volume-dependent electron-energy terms in the inter-atomic potential are discussed.
Electric Conductivity and Density of Sodium-Rubidium and Sodium-Cesium Acetate Molten Mixtures
Authors: Leonesi Dante , Cingolani Augusto , Berchiesi Gianfrancesco 
Published: February 2015

Abstract
The electric conductivities, densities and activation energies of RbC2H3O2 and CsC2H3O2 pure salts and (Na, Rb) C2H3O2 and (Na, Cs) C2H3O2 molten mixtures are reported. Deviations from addivity for the Vm , Λe and EΛ values are explained. The results for X2H3O2 where X=Na, K, Rb, Cs and for (Na, X) C2H3O2 , where X = K, Rb, Cs are discussed.
Konformationsuntersuchungen durch Elektronenspinresonanz Two-Jump-prozesse in Benzyl-phosphonium Salzen / Conformation Studies by Electron Spin Resonance Two-Jump Process in Benzyl-phosphonium Salts
Authors: Scheffler Klaus , Hieke Klaus , Schüler Paul , Stegmann Hartmut B. 
Published: February 2015

Abstract
The ESR spectra of 4-oxyl-benzyl-phosphonium-bromide radicals show a temperature dependence of the methylene protons and the phosphorus nucleus coupling constants which is explained by a hindered rotation of the phenoxyl ring of the radicals. Furthermore compounds with different phosphor substituents exhibit the phenomenon of a two jump process. This effect is described by an isomerisation of two symmetric radical conformations. Activation energies for this process are found to be around 7 kcal/Mol. The conformation of the radicals can be discussed as staggered ethane analogues. A lower limit value for the hyperconjugation Bᴾ -parameter is proposed.
Order Parameter Temperature Dependence of Some Nematic Liquids Related to Magnetic and Optical Anisotropies
Authors: Ibrahim I. H. , Haase W. 
Published: February 2015

Abstract
The diamagnetic susceptibilities, refractive indices and densities were measured as a function of temperature for three 4,4'-disubstituted benzoic acid-phenylester compounds. The polarizabilities were calculated using the Vuks formula and Neugebauer's relations. The orientational order parameters obtained from the magnetic and from the optical data as a function of temperature, in the absence of single crystal data, were compared.
Reaction of Vanadyl Ions with Alkyl Dinitriles
Authors: Al-Janabi Monther Y. , Ali Naseef J. 
Published: February 2015

Abstract
New complexes were prepared from the reaction of vanadyl ion with malononitrile and succinonitrile. Both complexes were found to exhibit a decrease in C ≡ N streatching frequency.
The reaction of vanadyl ion with malononitrile ion gives a complex in which the C ≡ N stretching frequency is increased. The increase or decrease is related to the type of bonding and to the difference in π-back bonding.
Untersuchung der elektrischen Leitfähigkeit homologer N-(4-n-Alkyloxybenzyliden)-4'-n-butylaniline im nematischen und smektischen Phasenbereich / Investigation of the Electrical Conductivity of Homologous N-(4-n-alkoxybenzylidene)-4'-nbutylanilines in the Nematic and Smectic Phases
Authors: Heppke G. , Schneider F. , Sterzl A. 
Published: February 2015

Abstract
Investigation The electrical conductivity of the first eight homologous N-(4-n-alkoxybenzylidene)-4'-n-butylanilines is investigated in the isotropic, nematic and smectic phases using the electrolyte tetra-butylammonium picrate. The anisotropy ratio of the electrical conductivity shows pretransition behaviour in the nematic phases close to the transition to the smectic phases. This behaviour be-comes more distinct with increasing alkyl chain length of the liquid crystals. In the nematic phase of 40·4 an anisotropy ratio of V = 0.55 is determined at the lowest electrolyte concentration. Values of about V=0.05 were found in the smectic phases of several homologues. In the nematic phase, an increase of the electrolyte concentration effects an increase of the anisotropy ratio. This effect is systematically enhanced with increasing alkyl chain length.
Investigation of the 1H Spin-Lattice Relaxation in Polycrystalline NH4ReO4 Induced by Mechanical Sample Rotation
Authors: Rager H. 
Published: February 2015

Abstract
Measurements of the proton spin-lattice relaxation time, T1 , in polycrystalline NH4ReO4 have shown that mechanical sample rotation in the static magnetic field reduces T1 for proton magnetic resonance frequencies within the range 30 - 42 MHz. The rotation induced proton spin-lattice relaxation times, T1
′, were measured at different Larmor frequencies, sample rotation frequencies, and temperatures. At room temperature T1
′ increases with increasing proton Larmor frequency. The dependence of T1
′ on sample rotation frequency and temperature is small. The "normal" proton T1 times were determined as a function of temperature at 30 and 42 MHz. From these measurements an average activation energy of 2.4 kcal/mole was obtained for the NH4
+ reorientation. The "normal" spin-lattice relaxation behavior was observed to be non-exponential at 30 MHz above 200 K and at 42 MHz above 260 K and is nearly independent on temperature above 300 K.
Zum Rotationsspektrum des InBr / On the Rotational Spectrum of InBr
Authors: Tiemann E. , Köhler U. , Hoeft J. 
Published: February 2015

Abstract
The hyperfine structure of the rotational transition J = 1→2 in the frequency range of 6.6 GHz was measured. The analysis yields the following quadrupole coupling constants:
eqvQ (115In) = [-634.62 + 2.52 (ν+1/2) ± 0.45] MHz,
eqvQ (79Br) = [110.38 + 0.50 (ν+1/2) ± 0.50] MHz,
eqvQ (81Br) = [91.88 + 0.45 (ν+1/2) ± 0.50] MHz.
The new determinations are consistent with the systematic trends of the III/VII diatomic molecules and remove the discrepancies of the older measurements of Barrett and Mandel1.
Formation of Periodic Ripples in a Surface Skin
Authors: Fischer Fred 
Published: February 2015

Abstract
A solid elastic skin on a liquid surface aquires a periodic ripple formation when a compressive strain surpasses a critical value. From a calculation the ripple wavelength is found to be proportional to the 3/4th power of the skin thickness. This instability can be described as a kind of second order phase transition, where a relative amplitude of the ripple wave is the order parameter. In addition, when the skin area is abruptly compressed the ripple wavelength depends on the magnitude of the compressive strain. Examples for skin rippling with wavelengths between 10 μm and 100 m are discussed.
Some Theoretical Considerations About the Excited Singlet and Triplet States of Diformamide and N-Methyl Diformamide
Authors: Marañon Julio , Sorarrain Oscar M. 
Published: February 2015

Abstract
The molecules of diformamide and N-methyl diformamide are analysed using the CNDO-CI method. Several excited singlet and triplet states corresponding to the three possible conformers and charge distributions are discussed.
On the Mechanism of CaWO4 Formation in the Solid State from CaO and WO3
Authors: Flor Giorgio , Massarotti Vincenzo , Riccardi Riccardo 
Published: February 2015

The formation in the solid state of CaWO4 from CaO (single crystal) or Ca3WO6 and WO3 was investigated by the contact method between 800 and 1000 °C in air and in argon.
The results obtained indicate that these reactions are governed by the diffusion of the W6+ and O2- ions.
From the CaWO4 structure, along with the lattice disorder predominant in this compound (0 vacancies and 0 interstitials) and the values of ionic mobilities, it was possible to state that the oxygen diffusion, via V0
2·, represents the rate - determining step in the considered reactions
Generalized Peierls-Boltzmann Transport Equations for Phonons and Local Excitation Kinetics
Authors: Kaiser Fr. , Wagner M. 
Published: February 2015

Abstract
The Peierls-Boltzmann transport equation for phonons is re-formulated and modified by means of sequences of transport and statistical postulates. The transition probabilities within the collision term are expanded in a comprehensive way. The resulting nonlinear kinetic equations are applied to a simple model system, i. e. a local excitation coupled to a transport system. The steady state solutions reveal the possibility of a hysteresis-type of "transport phase transitions" from the "thermo­ dynamic" branch to a "nonthermodynamic" one via a cumulative excitation. The stability of the solutions is checked and the approximations are discussed.
Isotope Effect of the Pure 35Cl and 37Cl Quadrupole Resonance Spectra in CHCl2COOH and CDCl2COOD
Authors: Rager Helmut , Wergin Alexander 
Published: February 2015

Abstract
The temperature dependence of the pure nuclear quadrupole resonance of 35Cl and 37Cl in solid CHCl2COOH and CDCl2COOD has been measured. The spectra are doublets according to two dif­ferent sites, Cl (I) and Cl (II), of the chlorine atoms in the CXCl2 group (X = H,D). In CHCl2COOH and CDCl2COOD the 37Cl spectra became unobservable above 198 K and 175 K and the 35Cl spectra vanished at 238 K and 226 K, respectively. The temperature dependence was calculated using the Bayer-Kushida theory which gives a satisfactory approach in the case of the compounds investigated here. A small difference has been found in the temperature dependence of the resonance frequen­ cies for CI (I) and CI (II) in both the CHCl2 and CDCl2 group, which is probably due to differences in the bond lengths of CI (I) and CI (II). Furthermore, there is a different temperature dependence of the resonance frequencies of the chlorine isotopes at the sites CI (I) and CI (II). This gives evi­ dence for the so-called isotope effect: i. e. there are slightly different thermal motions for the chlorine isotopes which are involved in the averaging of the electric field gradient tensor. The re­ placement of protons by deuterons gave a shift of the resonance frequencies of about 20 kHz to lower values. This may be primarily caused by effects of deuteration on the electronic structure.
Experimentelle und Quantenchemische Untersuchungen der Dipolmomente von Substituierten Stilbenen im Ersten Angercgten Singulettzustand / Experimental and Quantum Chemical Investigations of Dipole Moments of Substituted Stilbens in the First Excited Singlet State
Authors: Kawski A. , Gryczyński I. 
Published: February 2015

Abstract
The values a/a3 (α = polarizability), the Onsager cavity radii a and the dipole moments μe of six substituted stilbens in the fluorescent state have been determined. It is shown that if the dipole moment of the lowest excited singlet state μe is parallel to the dipole moment in the ground state μg, the values of μe and a can be determined from the solvent effects. Moreover, quantum chemical investigations of the dipole moments in the ground and excited states were carried out with the Pariser-Parr-Pople method and compared with the experimental values.
Periodic Ripples in a free Smectic A Surface Skin
Authors: Fischer Fred 
Published: February 2015

Abstract
A smectic A skin in a homeotropic texture on a liquid surface should form a periodic ripple when a horizontal compressive strain exceeds a critical value. The ripple wavelength is proportional to the fourth root of the skin thickness. In all practical cases the critical strain should be inversely proportional to the skin thickness. For a skin thickness approaching molecular dimensions, the critical strain has to be kept low by a small surface tension in order to avoid the formation of dislocations.
The Microwave Spectrum of Silylisothiocyanate, SiH3NCS
Authors: Dössel K.-F. , Sutter D. H. 
Published: February 2015

Abstract
The microwave spectra of 15N-and 13C-substituted SiH3NCS were recorded in the frequency region between 8 and 40 GHz. Combining the resulting rotational constants with values obtained previously for other isotopic species, the complete restructure of the heavy atom chain could be determined. This leads to the following rs-bond distances: rC-S = l-5745 Å, rN-C = 1.2208 Å, and rSi-N = 1.6725 Å. From Stark effect splittings the electric dipole moment of the most abun­dant species was determined for the ground vibrational state and for the first excited state of the lowest frequency bending vibration ν10 . The values are <ν10=0 | μz | ν10=0> = 2.38 + 0.02 D and <ν10=1, l=1| μz | ν10=1, l=1>=2.36 ±0.02D. The direction of the dipole moment is discussed. From the quadrupole hyperfinestructure of the J = 2→J′=3 rotational transition the 14N-quadrupole coupling constant could be determined as Xzz=0.75 MHz. The experimental results are compared to CNDO/2 calculations.