bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Parameter to Quantify Molecular Quasilinearity
Authors: Yamada Koichi , Winnewisser Manfred 
Published: February 2015

Abstract
A simple parameter is proposed for expressing the quasilinearity of molecules in a quantitative way. The parameter γ0 is defined on the basis of a discussion of the separation of variables in the Born-Oppenheimer approximation. The parameter γ0 assumes the value +1 for bent molecules and -1 for linear molecules. The range from -1 to +1 traces the transition of a vibrational degree of freedom in the linear configuration of a polyatomic molecule into a rotational degree of freedom in the bent configuration. The sequence of molecules along this parameter is shown and model calculations are carried out to further illustrate the physical interpretation of the parameter.
Analyse der Fluoreszenz von C6D6 -Mischkristallen durch IR-Modulation
Authors: Marquard J. , Aurich F. , Schumacher K. D. 
Published: February 2015

Abstract
Deuterated benzene mixed crystals are irradiated by intensity modulated i.r. at low temperatures. The i.r. causes a modulation of crystal temperature which in turn causes a modulation of fluorescence intensity of the crystal. Phase sensitive detection of fluorescence allows the assignment of bands to different trap emissions due to their different temperature dependences.
A simple kinetic model gives qualitative agreement with experiments.
Die erlaubten und verbotenen Resonanzübergänge der Mn2+ -Ionen in CeO2/ The Allowed and Forbidden Resonance Transitions of Mn2+-Ions in CeO2
Authors: Dräger K. , Wolfmeier U. 
Published: February 2015

Abstract
The absorption behaviour of Mn2+ -ions in CeO2 has been investigated and interpreted for the first time. Beside the hyperfine-multiplett with selection rules ΔM =1 and Δm = 0 we observed forbidden transitions with ΔM = 1 and Δm=± 1 At T = 29Q K the line width is rather small and amounts to 2.5 G. The entire spectrum can be described by an isotropic spin-Hamilton operator with g=1.9989 and A = 86.36·10-4 cm -1 . It is shown for Mn2+ in the crystal-field of oxygen-ions that there is a linear relationship between the hyperfine coupling constant A and the coordination number.
Thermoelectric Power of the Systems AgI-Ag2 XO4 (X=Mo, W)
Authors: Schiraldi Alberto , Pezzati Elisabetta 
Published: February 2015

Abstract
Determinations of the initial thermoelectric power were carried out at 1000 K in the whole composition range of the molten systems AgI-Ag2XO4 (X = Mo, W). For the composition XAgI= 0.8 the investigation was extended to the variation of the thermal emf at the “melting point” of the electrochemically noteworthy glass-like phases, obtained through rapid quenching of the melt. The hypothesis that these glass-like materials could keep the melt configuration at room temperature is contradicted by the results on the molten systems; more complex interpretations, based on the behaviour of the thermal emf at the “m.p.” are proposed.
The Emission Coefficient of the Continuum in an Argon and Nitrogen Plasma at High Temperatures
Authors: Erhardt K. , Meyer I. , Stritzke P. 
Published: February 2015

Abstract
The continuum emission of an argon-and nitrogen plasma developed in an electrical discharge has been investigated in the wavelength range from 3000 Å to 6700 Å. To this purpose the time-and radial dependent plasma parameters such as temperature and the total pressure have been determined in the high conducting stage of the spark by measuring several line intensities. The continuum coefficient was calculated from these data according to the Kramers-Unsöld theory. The comparison of the theoretical and the measured values shows deviations which are discussed. In the case of the argon continuum the ξ-factors for T = 14 000 K agree with the calculated values of Schlüter and the experimental ones of Schulz-Gulde. In the case of the nitrogen plasma the ξ-fac­tors have been determined in the temperature interval from 18 000 K to 45 000 K. Since at these temperatures the particles NII-NIV contribute to the total continuum coefficient, the measured ξ-factors can only be correlated to ξII, ξIII, ... in a narrow temperature range. The measured cor­rection factor ξ for λ = 5050 Å has been applied to determine the temperatures and the pressure of a laser produced spark. The plasma parameters agree with those determined by measuring the line-intensity of the NII-line at 5000 A.
Excimer Formation of 1-Pyrene-Sodium Sulphonate in Inverse Micelles
Authors: Miller Dennis J. , Klein Uwe K. A. , Hauser Manfred 
Published: February 2015

Abstract
Micelle aggregation numbers may be obtained from the fluorescence time dependence of excimerforming solubilised substances. The micellar system cetyldimethylbenzylammonium chloride (CDBA)/water/benzene was studied using 1-pyrene sodium sulphonate as the fluorescent probe. Solubilised water increases the CDBA aggregation number. It is shown that the micelles are poly-disperse at lower CDBA concentrations. The influence of concentration and aggregation number on the photostationary excimer/monomer fluorescence intensity ratio of the solubilised probe is discussed.
High-frequency Surface Waves in a Current Carrying Hot Plasma Column
Authors: Shivarova A. , Zhelyazkov I. 
Published: February 2015

Abstract
The propagation of high-frequency axially-symmetric surface waves along a current-carrying hot plasma column in a glass tube is investigated by means of a kinetic plasma model. The wave spectrum and the wave damping rate are obtained. Our results agree with the experimental data for surface wave propagation in a gas-discharge plasma at low pressures. It is found that the wave damping is mainly due to the Landau mechanism.
Singlet-Exciton Energy Transfer in Naphthalene Doped with Anthracene Following Two-Photon Picosecond Excitation: Dependence on Dopant Concentration
Authors: Auweter H. , Mayer U. , Schmid D. 
Published: February 2015

Abstract
The time dependence of the sensitized fluorescence of anthracene-doped naphthalene crystals following two-photon picosecond excitation was studied for various dopant concentrations. The experimental results indicate that the characteristic of the energy transfer rate is significantly different for different anthracene concentrations. This behaviour is discussed in terms of different transfer mechanisms taking place at low and high dopant concentrations.
Normalkoordinatenanalyse und mittlere Schwingungsamplituden für Cl5SbOPCl3 , Cl5NbOPCl3 und Cl5TaOPCl3
Authors: Brockner Wolfgang , Cyvin Bjørg N. , Cyvin Sven J. 
Published: February 2015

Abstract
A normal coordinate analysis was performed for some Cl5MOPCl3 molecules (M = Sb, Nb, Ta). The final force field in terms of a described set of symmetry coordinates is reported for Cl5SbOPCl3. The initial force field for Cl5SbOPCl3 was applied to calculate the vibrational frequencies of the Cl5NbOPCl3 and Cl5TaOPCl3 adducts. An assignment of the vibrational frequencies of the title compounds and the corresponding potential energy distribution terms are given for Cl5SbOPCl3 . For the Cl5SbOPCl3
Zur Feinstruktur des Verlaufs der Adsorptionswärme mit der Belegung von Aromaten auf Silber / Investigations on the Fine Structure of the Adsorption Heat-Coating Curve Obtained by Covering Silver with Aromatic Hydrocarbons
Authors: Knappwost A. , Raschti M. , Ankara Ü. 
Published: February 2015

Abstract
Isosteric adsorption heats have been determined from the temperature dependences of equilibrium pressures, which in turn have been obtained from sets of very precisely measured adsorption isotherms. The dependence of the isosteric adsorption heat on the coating of the silver surface shows a remarkable structure: whenever a layer of adsorbate is filled up, inner rotations are inhibited, which results in a peak in the adsorption heat-coating curve. The adsorption isotherms of toluene, adamantane and benzotrifluoride on highly dispersed silver were measured with an ultra-sensitive adsorption balance. The nearly spherical adamantane enabled an exact determination of the specific surface area of the adsorbent. From their respective space requirements it followed that toluene is adsorbed in ortho- and meta-positions, whereas benzotrifluoride is adsorbed with its three F-atoms on the silver surface. The energy of rotation of the CH3-and CF3-groups could also be determined.
On the Use of a Low Current Argon Arc with a MgF2-Window as a VUV-Transfer Standard of the Spectral Radiance (125nm≦λ≦335nm)
Authors: Einfeld D. , Grützmacher K. , Stuck D. 
Published: February 2015

Abstract
The spectral radiance Lλ (λ) of a low current argon arc (current: 10 A, power requirement: ≦1.5 kW, pressure: 1.2 bar, gas: A) has been calibrated with a relative uncertainty of 5% in the wavelength range between 125 nm and 335 nm by means of the electron synchrotron radiation of DESY (Hamburg, Germany). Lλ (λ) exceeds generally the spectral radiance of the carbon arc and the commercially available deuterium lamps by more than one order of magnitude. A significant reduction of the transmittance τ(λ) of the MgF2-window, inserted for the sealing of the arc chamber has been observed in the entire wavelength range when the low current argon arc has been flanged to a vuv-optical system. The behaviour of the transmission factor of the MgF2-window under the influence of increasing times of exposure to arc radiation has been investigated as a function of wavelength. The reduction of the transmission factor of the MgF2-window in the uv (λ > 185 nm) is nearly negligible ( < 2 % over an operating time of 30 hours) when the arc has been utilized without a connection to a vuv-optical system
On the Convergence of the Calculated Spin-spin Coupling Constant of HD
Authors: Trivedi H. P. 
Published: February 2015

Abstract
It is shown that the concurrence of the results obtained by varying the self coupling energy, the total second order energy and the cross coupling energy independently can be readily accomplished. In addition, it is possible to arrange to obtain any pre-specified value for the coupling constant. On this basis it is suggested that it might be dangerous to construe the concurrence of calculated results as an indication of convergence in practice.
Isotopic Abundances Measurements a Key to Understanding the Oklo Phenomenon
Authors: Ruffenach J. C. , Hagemann R. , Roth E. 
Published: February 2015

Abstract
The Oklo natural nuclear reactors have been studied mainly by isotopic and chemical analyses of uranium and fission products. Interpretation of these analyses allows parameters which characterize these reactions (flux, fluence,...), and also the age and duration of the nuclear reactions to be evaluated. The mechanisms and extent of fission-product migration can also be discussed. The behaviour of various elements formed in the Oklo uraninite and in oxyde fuels of pressurized water reactors is compared and found to be similar. Therefore, experience gained from the study of the Oklo phenomenon can provide valuable information on the long-term storage of radioactive wastes in geological media.
Resonant Microwave Absorption in an Overdense Plasma Column
Authors: Böhm G. 
Published: February 2015

Abstract
A resonant coupling mechanism is presented which leads to nearly full absorption of an electromagnetic wave in an overdense plasma column. In the resonance case a strong enhancement of the electric field strength within the plasma is found. Under certain conditions this high electric field strength causes parametric excitation of plasma waves in the underdense edges of the discharge. It turned out that the occurance of this decay process is mainly determined by the density gradients in the plasma.
Infrared Absorption of Concentrated Aqueous LiCl Solutions to High Pressures and Temperatures
Authors: Valyashko V. M. , Buback M. , Franck E. U. 
Published: February 2015

Abstract
The infrared absorption of the O-D stretching fundamental of HDO in concentrated aqueous (HDO/H2O) LiCl solutions to a maximum of 40 mole percent salt has been measured. Data for the wavenumber of maximum absorption, ν̄(max), and for the integrated molar absorptivity B up to pressures and temperatures of 2800 bar and 350 °C, respectively, are reported and discussed. Toward high salt concentrations, the dependence of ν̄(max) on temperature and on LiCl concentration decreases. The wavenumber data indicate a transition from "water-like" to "melt-like" behaviour at about 12 to 15 mole percent LiCl.
Improved Versions of Fielek Model for BCC Transition Metals
Authors: Khanna R. N. , Rathore R. P. S. 
Published: February 2015

Abstract
Three improved versions of the Fielek Model are developed and discussed. The first model uses a modified Bhatia scheme for the volume interaction in place of the Krebs scheme. The second and third model assumes the core-core couplings to be central pairwise effective upto first neighbours only. The second model describes the d-shell-d-shell interaction on the same lines as those adopted for core-core interactions, while the third model assumes these interactions to be of the many body type. Suitable equilibrium conditions for the second and the third model are developed.
These improved versions are employed to derive dispersion relations in tantalum. Comparison of these relations with-each other and also with the experimental findings leads to some important conclusions regarding the nature and range of the interactions coupling the various constituents of a bcc transition metal like tantalum.
Faddeev Equations in the Functional Quantum Theory of the Non-Linear Spinorfield
Authors: Ramacher U. 
Published: February 2015

Abstract
Starting with a linear partial differential operator for a certain system of transition amplitudes associated to a state |a> with baryon number ρ(a) we derive an equation in the ρ(a)-sector of the Functional space which provides the state |a> with an effective potential caused by the polarization cloud. With regard to the needs of n-body scattering we then undertake a cluster decomposition of the effective potential. In particular, we derive the relativistic analoga of Lippmann-Schwinger-and Faddeev equations.
Functional Quantum Theory of the Nonlinear Spinorfield as a Lepton-Hadron Model with Quark-Confinement. II
Authors: Stumpf H. 
Published: February 2015

Abstract
The nonlinear spinorfield with Heisenberg's dipole regularization is interpreted as a lepton-quark system. In Section 1, a nonlinear spinorfield equation for two lepton-quark generations is derived by physical arguments and the Heisenberg dipole regularization is formulated for this model. In Section 2, corresponding dynamical equations for local fermion and local boson states are deduced by means of functional quantum theory and their properties are discussed. In Section 3, with this formulation the lowest order »S'-matrix of elastic lepton-lepton scattering is calculated and is shown to be identical with the results of the corresponding process in quantum electrodynamics resp. weak interactions. The coupling of the local bosons to local fermions is universal, i.e. independent of special lepton or quark representations. Numerical calculations of local boson masses and coupling constants will be given in subsequent papers.
Nitrogen Quadrupole Coupling in the Rotational Spectrum of l-Isocyanoprop-2-yne, HC ≡ CCH2NC
Authors: Krüger M. , Dreizler H. 
Published: February 2015

Abstract
The rotational spectrum of l-isocyanoprop-2-yne, HC≡CCH2NC, has been measured in the vibrational ground state by microwave Fourier transform spectroscopy from 5 to 26.5 GHz. The nuclear quadrupole hyperfine splittings due to 14N have been analysed to obtain the coupling constants χaa = 290.3(78) kHz, χbb = 10.6(80) kHz and χcc= -300.9(80) kHz
35Cl NQR, Crystal Structure, and Pyroelectricity of 2,3-Dichloro-1,4-naphthoquinone
Authors: Brummer Stefanie , Sohling Ulrich , Weiss Alarich 
Published: February 2015

Abstract
The 35Cl NQR spectra of the two phases (phases I and II) of 2,3-dichloro-1,4-naphthoquinone were studied from 77 to 394 K. The crystal structure determination of the triclinic phase (phase I) was refined by single crystal X-ray diffraction. Phase I crystallizes in the space group C1
i-P1̄. The unit cell (Z = 4) has the dimensions a = 1614.3(4) pm, 6 = 828.1 (3) pm, c = 733.2(3) pm, α = 67.02(1)°, β = 82.55(1)°, γ = 89.77(1)°. In the temperature range 439≦ TI→II/K≦447 a unidirectional phase transition I → II is observed. Phase II is orthorhombic, space group C5
2v-Pb21a. The bond distances d(C-CI) and the 35Cl NQR frequencies correlate quite well according to the theory: v(35Cl) ~ (d(C-CI)) 3- The multiplicity of the 35Cl NQR spectra is discussed. Pyroelectricity studies on phase II are reported. The pyroelectric coefficient depends little on the temperature, 8.3≦px/μCm-2 K-1≦10.7 in 103 ≦T/K≦343.
NQR Investigations of La3-x Ba3+xCu6O3 , (x = 0, 0.75, 1)
Authors: Okuda T. , Ueki T. , Yamada K. , Ichiba S. , Atobea K. , Yoshida H. 
Published: February 2015

Abstract
NQR spectra due to 63Cu and 139La have been recorded for La3-xBa3+xCu6O (x = 0, 0.75, 1). Two groups of 63Cu NQR lines were observed (around 20-23 MHz and 29-36 MHz). The former is assigned to the Cu atoms in the CuO4 square planar groups, and the latter to that in the CuO s square pyramidal group. For the 63Cu NQR lines in La3Ba3Cu6O , the time dependent NQR spectra and the temperature dependence of NQR frequencies were observed.
Molecular Motions in (CH3)3XCl, X = Sn and Pb. NMR Investigations and Crystal Structure Study of (CH3)3PbCl and CH3SnBr3
Authors: Zhang Da , Dou Shi-Qi , Weiss Alarich 
Published: February 2015

Abstract
The molecular motion in (CH3)3XCl, X = Sn and Pb has been investigated by measurement of the second moment M2(1H) as function of temperature in the range 95 < T,/K<345. The methyl groups in both compounds rotate freely over the whole temperature range studied. In (CH3)3SnCl the C'3-rotation of (CH3)3Sn-group about the Sn CI axis sets in above 273 K. To explain the NMR and INS results, the crystal structures of (CH3)3PbCl and CH3SnBr3 were determined by single X-ray diffraction. (CH3)3PbCl crystallizes in a monoclinic space group C3
2-C2, a = 1276.7(3) pm, b = 982.3(3) pm, c = 547.0(2) pm, ß = 91.12(1)°; Z = 4, R = 0.035. CH3SnBr3 crystallizes in an orthorhombic space group D16
2h-Pnma, a = 643.0(3) pm, b= 1005.3(4) pm, c= 1148.0(4) pm; Z = 4, R =0.057
Low-Frequency Electromagnetic Properties of an Alternating Stack of Thin Uniaxial Dielectric Laminae and Uniaxial Magnetic Laminae
Authors: Patrick S. Reese , Lakhtakia Akhlesh 
Published: February 2015

Abstract
Analysis is carried out for an alternating arrangement of laminae which have either uniaxial permittivity or uniaxial permeability dyadics. The unit cell is constructed of two laminae such that the ones with the uniaxial permittivity dyadic alternate with the ones with the uniaxial permeability dyadic through the stack. It is assumed that both dyadics have the same optic axis. The 4-vector method is utilized to construct a characteristic matrix for the two-lamina unit cell. After assuming that each lamina is electrically thin, the properties of an equivalent medium are obtained: both the permeability and the permittivity dyadics of the equivalent medium are biaxial
A Comparative Study of the BJH- and MCYL-Type Potentials Applied to the Gaseous Water Dimer
Authors: Slanina Zdenek 
Published: February 2015

Abstract
Various refined potentials describing the intra- and inter-molecular force fields of water molecules arc used to calculate the properties of the gas-phase water dimer. The intra-molecular parts have been taken from spectroscopic or quantum-chemical sources. The minimum energy structure was found iteratively using the first derivatives of the potential; the force-constant matrix was constructed by numerical difierentation. A quite close agreement between the Bopp-Jancso-Heinzinger and the Matsuoka-Clementi-Yoshimine-Lie potentials is found. The treatment is applied to seven observed water-dimer isotopomeric isomerizations
Molecular Dynamics Study of Microscopic Mechanism of Diffusion in Li2SiO3 System
Authors: Habasaki Junko 
Published: February 2015

MD simulation has been performed to learn the microscopic mechanism of diffusion of ions in the Li2SiO3 system.
The motion of lithium ions can be explained by the trapping model, where lithium is trapped in the polyhedron and moves with fluctuation of the coordination number. The mean square displacement of lithium was found to correlate well with the net changes in coordination number.
On the Entropy of the Hard Sphere Fluid
Authors: Baranyai Andräs , Evans Denis J. 
Published: February 2015

Abstract
The expansion of the entropy into one-body, two-body, three-body, etc. contributions was applied to estimate the excess entropy of the hard sphere fluid. Configuration samples provided by computer simulation were used to determine the two-particle and three-particle correlation functions. The results show that even at intermediate densities a non-negligible part of the structural information is represented by four-body and higher order correlations.
Calculation of Lower Bounds to Energy Eigenvalues of He, Li+ and Li by Means of the Effective Field Method
Authors: Fleischhauer Jörg , Schleker Wolfgang , Raabe Gerhard 
Published: February 2015

Abstract
Two versions of the effective field method have been applied to calculate lower bounds to the energy eigenvalues of the small systems He, Li+, and Li. Although our modified method leads to an improvement compared with the originally proposed scheme, the results are still far from being satisfying.
NQR Study of the Pinning and Depinning of the Incommensurate Modulation Wave in the Presence of Impurities
Authors: Milia F. , Papavassiliou G. , Anagnostopoulos A. 
Published: February 2015

Abstract
High temperature-resolution NQR measurements in an ultra pure Rb2ZnCl4 crystal and a mixed [Rb1-x(NH4)x]2ZnCl4 crystal with a controlled amount of impurities (x = 0.01) verify the existence of a temperature region where the characteristic incommensurate line splitting is averaged out. The results show that for the system with high purity the averaging of the incommensurate splitting is due to large thermal fluctuations. In contrast, for the mixed crystal the added impurities seem to play the predominant role.
7Li-MR Studies on Molecular Motion of Hydrated Lithium Ions in Concentrated Aqueous Solutions of LiCl, LiBr, and LiSCN at Low Temperatures
Authors: Hasebe Tooru , Tanaka Kazuko 
Published: February 2015

Abstract
Nuclear spin-lattice relaxation times, T1, of 7Li in 13.8mol/kg LiCl-H2O and 12.3 mol/kg LiCl-D2O solutions have been measured in the temperature range 80K-313K. They showed similar temperature dependences with the same minimum values (27 ± 1 ms) which proved that the electric quadrupole interaction is dominant for the relaxation of 7Li-NMR. The T1 and T2 values of 7Li-NMR in concentrated aqueous solutions of LiCl (8-14 mol/kg), LiBr (8-10 mol/kg) and LiSCN (8-14 mol/kg) at 80 K to 300 K have been studied to obtain information concerning the dynamic properties of Li+ ions and the effect of anions. T1 at temperatures higher than the glass transition point is governed by a tumbling motion of the hydrated lithium ions.