bluuebunny/crossref_metadata_2025_split huggingface dataset:
121,123Sb and 209Bi Nuclear Quadrupole Resonance Study of Complex Compounds of Antimony(III) and Bismuth(III) in the Temperature Range 77-400 K
Authors: Zemnukhova L. A. , Davidovich R. L. 
Published: February 2015

Abstract
A large number of solid fluoride and heteroligand acidocomplex compounds of antimony(III) and bismuth(III) with single and mixed cations has been prepared from aqueous solutions. Their crystal structures and 121,123Sb and 209Bi NQR spectra have been investigated in a wide temperature range.
35Cl NQR, 1H NMR, and X-Ray Diffraction Studies in a Hydrogen Bonded Complex Na2PtCl6 · 6H2O
Authors: Miyoshi Hiroshi , Horiuchi Keizo , Sakagami Narumi , Okamoto Kenichi , Ikeda Ryuichi 
Published: February 2015

Abstract
The 35Cl NQR frequencies, spin-lattice relaxation time and 1H NMR relaxation time were measured on crystalline Na2PtCl6 • 6H2O at 77-350 K. The presence of three nonequivalent chlorine sites found by X-ray diffraction measurement is in agreement with the observed three NQR lines, which have different temperature dependences attributable to differences in the direction of H-bonding with water molecules. The three NQR lines correspond to three kinds of chlorines with different Pt-Cl distances and H-bond directions.
Remarks on Some Basic Issues in Quantum Mechanics
Authors: Englert Berthold-Georg 
Published: February 2015

Abstract
Two-way interferometers with which-way detectors are not only of importance in physical research, they are also a useful teaching device. A number of basic issues can be illustrated and discussed, even at the level of undergraduate teaching. Among these issues are: the physical meaning of a state vector; entangled systems; Einstein-Podolsky-Rosen correlations; statistical operators and the as-if realities associated with them; quantum erasure; Schrödinger's cat; and, finally, wave-particle duality.
Phase Structures in the Micromaser Photon Statistics
Authors: Bergou János A. , Bogár Pál 
Published: February 2015

Abstract
In the photon number distribution p(θ,k) of the micromaser, distinct structures are formed by the ridges connecting the peaks in the θ-k space. We refer to these structures as phases. By a simple condition we can distinguish between "semiclassical" and "quantum" regimes of operation near and far above threshold, respectively. In the semiclassical regime, the equations of state of the phases θ= θ(k) are monotonous and coincide with the steady state solutions of the semiclassical theory. They reflect typical features of the micromaser dynamics. The transition jumps, e. g., between the phases decrease with increasing pumping parameter θ, signifying the onset of the Jaynes-Cummings collapse. On increasing 9 further, the phases first disintegrate and then restructure into new kinds of phases in the quantum regime. The equations of state are no longer monotonous. Large single peaks, the quantum island states (QIS), develop in the neighborhoods of minima. The system undergoes oscillations between two kinds of quantum island states, QIS- and QIS+ , as a function of θ. The disintegration and transformation of phases recur periodically as θ is varied, and the phases in the semiclassical region are followed by consecutive phase structures in the quantum regime. The subsequent collapses and revivals of phases are directly connected to the Jaynes-Cummings collapse and revival. The observation of these phase structures and the accompanying QIS is experimentally feasible.
Dynamical Description of Coulomb Dissociation
Authors: Typel S. , Wolter H. H. 
Published: February 2015

Abstract
We present a simple and efficient method for a fully dynamical treatment of Coulomb excitation in the semiclassical approximation by solving the time-dependent Schrödinger equation. It allows to investigate the importance of higher order effects in the breakup process. The method is applied to the Coulomb breakup of 7Li scattered on 197 Au at 42 MeV projectile energy.
Compatibility of Neutron Star Masses and Hyperon Coupling Constants
Authors: Huber H. , Weigel M. K. , Weber F. 
Published: February 2015

Abstract
It is shown that the modern equations of state for neutron star matter based on microscopic calculations of symmetric and asymmetric nuclear matter are compatible with the lower bound on the maximum neutron-star mass for a certain range of hyperon coupling constants, which are constrained by the binding energies of hyperons in symmetric nuclear matter. The hyperons are included by means of the relativistic Hartree-or Hartree-Fock approximation. The obtained couplings are also in satisfactory agreement with hypernuclei data in the relativistic Hartree scheme. Within the relativistic Hartree-Fock approximation, hypernuclei have not been investigated so far.
Structure and Dynamic Properties of Molten Lanthanum Tribromide
Authors: Okamoto Yoshihiro , Ogawa Toru 
Published: February 2015

Abstract
The structure of molten LaBr3 was investigated by X-ray diffraction and molecular dynamics simu-lations. It was found that the short range structure of molten LaBr3 is very similar to that of molten LaCl 3 , except for some structural features such as interionic distances based on the difference of anion sizes. In the MD simulation, the shear viscosity of molten LaBr3 was estimated from the structurally-optimized MD calculations.
Resistivity and Carrier Mobility of the SmBa2 Cu3 O6+x Superconductor with Different Oxygen Doping Levels
Authors: Spinolo G. , Ghigna P. , Chiodelli G. , Ferretti M. , Flor G. 
Published: February 2015

Abstract
DC conductivity measurements between 15 and 300 K are reported for SmBa2 Cu3O6+x samples with different oxygen doping amounts (x) produced by annealing under appropriate high temperature and oxygen pressure conditions and quenching. Samples with x≥0.5 are superconductors: Tc ~60 K at x=0.7, Tc >80 K at ; x=0.9. The transition from superconduction to non-superconduction corresponds to the tetragonal to orthorhombic structural tran-sition and to the transition from semiconducting to metallic temperature dependence of the resistivity. Oxygen doping causes a sudden increase of hole mobility near x=0.5. Below this threshold, the be-havior of the carrier mobility is in agreement with an Anderson localization.
A Generalized Debye Scattering Formula and the Hankel Transform
Authors: Wieder Thomas 
Published: February 2015

Abstract
The diffracted intensity of an x-ray or neutron diffraction experiment is expressed as an integral over an atomic position distribution function. A generalized Debye scattering formula results. Since this distribution function is expanded into a series of spherical harmonics, an inverse Hankel transform of the intensity allows the calculation of the expansion coefficients which describe the atomic arrangement completely. The connections between the generalized Debye scattering formula and the original Debye formula as well as the Laue scattering formula are derived.
Rotational Spectra of Phosphorus Monosulfide up to 1 THz
Authors: Klein H. , Klisch E. , Winnewisser G. 
Published: February 2015

Abstract
The submillimeter-wave rotational spectrum of the PS radical in the electronic and vibrational ground state (X2 ΠI/2 , X2Π3/2) was recorded with the Cologne terahertz spectrometer in the fre-quency region between 540 GHz and 1.07 THz, covering rotational quantum numbers from J = 30.5 to 60.5. The PS radical has been produced by discharging PSCl3 buffered with Ar. For all transitions the Λ-doubling was resolved for both the 2ΠI/2 and 2Π3/2 states. For some transitions with ΔF = 0 the hyperfine structure (hfs) caused by the P-atom could partially be resolved even for rather high J values. Analysis of the complete rotational data set of PS allows the derivation of a full set of molecular parameters, including the rotational constants B, D, H, the fine-structure constants A,γ , Dγ , the parameters for the Λ-doubling p, Dp , q, and the magnetic hyperfine constants a, b, c, d, CI. All parameters have been determined, whereby a, c, and the nuclear spin rotation-constant CI were obtained for the first time.
Parasites and Pattern Formation
Authors: Ackermann J. , Kirner T. 
Published: February 2015

Abstract
Biological information is coded in replicating molecules. To maintain a given amount of in-formation a cooperative interaction between these molecules is essential. The main problem for the stability of a system of prebiotic replicators are emerging parasites. Stabilization against such parasites is possible if space is introduced in the model. Complex patterns like spiral waves and self-replicating spot patterns have been shown to stabilize such systems. Stability of replicating systems, however, occurs only in parameter regions were such complex patterns occur. We show that parasites are able to push such systems into a parameter region were life is possible. To demonstrate this influence of parasites on such systems, we introduce a parasitic species in the Gray-Scott model. The growing concentration of parasites will kill the system, and the cooperative Gray-Scott system will be diluted out in a well mixed flow reactor. While considering space, in the model stabilizing pattern formation in a narrow parameter region is possible. We demonstrate that the concentration of the parasitic species is able to push the system into a region were stabilizing patterns emerge.
Influence of the rf Field Inhomogeneity on Nutation NQR Spectra of Spin 3/2 Nuclei in Powders
Authors: Sinyavsky N. , Maćkowiak M. , Velikite N. 
Published: February 2015

Abstract
The influence of the rf field inhomogeneity on the NQR nutation spectra of spin / = 3/2 nuclei in powder samples is investigated. To eliminate the rf field inhomogeneity effects, a method of reconstruction of the NQR nutation spectra, based on finding the deconvolution of the Fourier nutation spectrum with a function of the rf field distribution, is used. The method is successfully demonstrated for simulated and experimental NQR nutation spectra of 35C1 in TiCl4 . The lineshape analysis of reconstructed nutation spectra allowing the determination of the EFG asymmetry parameter is given. The real advantage of the proposed method is that the high-resolution nutation spectrum may be obtained for a sample filling up the entire coil.
Molecular Orientation in Uniaxial Liquid Crystal Phases as Studied by Electron Paramagnetic Resonance
Authors: Moryson Hanka , Bauman Danuta , Hilczer Wojciech , Hoffmann Stanislaw 
Published: February 2015

Abstract
The electron paramagnetic resonance spectra of 3/ß-doxyl-5α-cholestane dissolved in five liquid crystals have been recorded as a function of temperature in the isotropic and mesogenic phases. From these spectra the order parameter (P2) has been determined. The results have been com-pared with the data obtained from the optical birefringence measurements and from the polarized absorption spectra of the dichroic dye dissolved in liquid crystal host.
Al3+ Coordination in Cryolitic Melts: A Computer Simulation Study
Authors: Castiglione Michael J. , Ribeiro Mauro C. C. , Wilson Mark , Madden Paul A. 
Published: February 2015

The structures of melts containing cryolite have proved difficult to confirm, despite decades of study, on account of the high temperatures and corrosiveness of these melts. Raman spectroscopy has so far provided the majority of the insight into the aluminium coordination environments, but some of its interpretations are still debated.
In this paper we present the results of MD simulations on various NaF-AlF3 liquid mixtures using published potentials developed for the solid state and published Raman spectra.
High-pressure DTA Studies of the Phase Behaviors of 4-n -butyl-thiocyanobiphenyl (4TCB) and 4-w-pentyl-4’-n-phenyl-cyanocyclohexane (5HCP)
Authors: Massalska-Arodź M. , Würflinger A. , Büsinga D. 
Published: February 2015

Abstract
DTA measurements of 4-n-butyl-thiocyanobiphenyl (4TCB) and ρ-cyano-ρ’-pentylphenyl-cyclohex-ane (5HCP) have been performed in the temperature range 220 K-390 K and pressures up to 400 MPa. For 4TCP a transition from a crystalline to a liquid crystal phase (probably smectic E) could be detect-ed at higher pressures > 90 MPa. The pressure dependence of the transition temperature has been estab-lished. At pressures lower than 88.7 MPa no transition of SmE into a crystal or into a glass has been found. For 5HCP only the melting curve was observed, in contrast to 5PCH, which displays a liquid crystalline nematic phase.
Mesophase and Glass Formation in Binary Systems of Caesium and Alkali-Earth Metal Butyrates
Authors: Mirnaya T. A. , Dradrah V. S. , Yaremchuk G. G. 
Published: February 2015

Abstract
The phase diagrams of the binary systems of non-mesomorphic components such as caesium-mag-nesium, caesium-calcium and caesium-barium butyrates have been studied by differential thermal analysis and hot stage polarization microscopy. Smectic liquid crystals are found in some composition ranges of the binaries with calcium and barium butyrates. The liquid crystal appearance in these systems is explained by the exhibition of latent mesomorphism of caesium butyrate. Glasses are obtained in all systems studied, the formation of vitreous optical anisotropic mesophase being revealed only for binary from caesium and barium butyrates.
Ammonium Ions Dynamics in NH4Br-Proton NMR T1 Measurements and Simulations
Authors: Goc R. , Wąsicki J. , Lewicki S. 
Published: February 2015

Abstract
Monte Carlo simulation of correlation functions for ammonium bromide have been carried out and the NMR relaxation times T1 resulting from these functions were calculated. Results of simulations are compared to experimental values of T1 measured in the temperature range 92 K to 292 K.
Tunneling Magnetoresistance in a Two-Layered La2-2xCa1+2xMn2O7Polycrystal
Authors: Zhou Tie-Jun , Yu Z. , Du Y. W. 
Published: February 2015

Abstract
By the sol-gel method, a polycrystal bulk of two-layered La2-2xCa1+2xMn2O7 with x = 0.2 was successfully synthesized. A high sensitive low-field TMR was found at low temperature.
Structure of Sputtered Amorphous Zr-Hf-Si Alloys
Authors: Pojtinger A. , Lamparter P. , Steeb S. 
Published: February 2015

Abstract
Amorphous (Zr,Hf)37Si63 alloys were produced by sputtering. Their total structure factors were determined by X-ray diffraction. Using the methods of isomorphous substitution and Reverse Monte Carlo simulation, the partial pair correlation functions were obtained. The results were compared with the partial functions of amorphous Ti40Si60. In the amorphous alloys under investigation the transition metal -metalloid correlation dominates the short range order.
On a Direct Superconducting Pairing Mechanism
Authors: Böhm Michael C. , Saal Christoph 
Published: February 2015

Abstract
We suggest that superconductivity can be traced back to a first-order interaction between the charge carriers which does not necessarily involve second-order electron-phonon coupling. For small molecular model systems it is demonstrated that the formation of Cooper pairs can lead to an attenuation of the destabilizing influence of the Pauli antisymmetry principle (PAP). We suggest that this attenuation of a fermionic quantum constraint is the driving force for the superconducting transition. Whenever the PAP is activated in single-particle hoppings of electrons, the corresponding moves reduce the electronic derealization; they raise the ensemble energy. The stability of a fermionic system is enhanced with decreasing influence of the PAP. Moves of Cooper pairs are not influenced by any quantum constraint of the intersite type. This behaviour differs from the well-known fermionic constraints. The quantum statistics of Cooper pairs is of a mixed type combining a fermionic on-site and a bosonic intersite behaviour. It coincides with the quantum statistics of so-called hard core bosonic ensembles. In the present work Cooper pair formation has been studied for smaller molecular models. The electronic Hamiltonian employed is of the two-parameter Hubbard-type. The solid state phenomenon superconductivity is correlated with the molecular concepts of “antiaromaticity” and “aromaticity”. Arguments are given which support the present interpretation.
Electrochemical Behavior of Ba2+ at Liquid Metal Cathodes in Molten Chlorides
Authors: Matsumiya Masahiko , Takano Masatoshi , Takagi Ryuzo , Fujita Reiko 
Published: February 2015

Abstract
The electrochemcal behavior of Ba2+ on several liquid metal electrodes (AI, Bi, Cd, Pb, Sn and Zn) in a NaCl-KCl equimolar solvent at 1000 K has been investigated by means of cyclic voltammetry and chronopotentiometry. The kinetic parameters and the diffusion coefficient for Ba2+ were determined by cyclic voltammetry with conventional, semi-integral, semi-differential methods and chronopotentiometry. It was revealed that on a liquid Pb electrode in the NaCl-KC1 system at 1000 K the quasi-reversible cathodic reaction Ba2+ + 2e- + Pb → BaPb takes place. In addition, the kinetic parameters and the diffusion coefficient agree well with the values determined by various electroanalyses. The possibility of alloy formation between Ba and Sn was also demonstrated in this paper.
Further Measurements of the Zonar Distribution of 18O in Synthetic Quartz Crystals
Authors: Klemm A. , Roller K. , Hoemes S. 
Published: February 2015

Abstract
The isotop effect δ18OF -δ18Os, measured between the face F and the solvent S of synthetic quartz crystals, grown at 1 kbar and 550-700 K, has been estimated to be 5.4, 18O being enriched in the solid.
Lineshape Analysis of 2D NMR and NQR Nutation Spectra of Integer and Half-Integer Quadrupolar Nuclei
Authors: Velikite N. , Sinyavsky N. , Maćkowiak M. 
Published: February 2015

Abstract
A lineshape analysis of the NMR and NQR powder nutation spectra of integer and half-integer quadrupolar nuclei is presented. Simulated NMR nutation spectra of spin I = 1 and 3 nuclei are reported. For I = 1 the formulas for the singularities of the NMR nutation powder patterns as a functions of η, e2Qq and 7B x are given. The NQR nutation powder patterns for spin I = 3/2, 5/2, 7/2, and 9/2 for different induced transitions are calculated, and some experimental aspects of the method are discussed. A universal empirical formula to facilitate the determination of the asymmetry parameter from the NQR nutation frequency singularities for any arbitrary spin or transition is found. The NQR nutation spectra for half-integer and integer spins are compared. For integer spins the two-frequency excitation of the nutation spectrum is analysed. Application of the 2D-nutation lineshape analysis for the determination of the quadrupole interaction parameters is emphasised.
New Mechanism for Facile Charge Transport in Polypeptides
Authors: Baranov L. Ya. , Schlag E. W. 
Published: February 2015

Abstract
An electronic hole migration accross a polypeptide chain is discussed with special reference to new ab initio computational results and to the experimental observations of Weinkauf et al. on the charge photoinjection into the polypeptide backbone. New mechanistic details for this efficient charge transport process are proposed. The process is viewed as a vibronically induced hole hopping between local aminoacid sites driven by large amplitude torsional motions of the floppy backbone.
Local Correlation's Potential for Noise Reduction and Symbolic Partitions
Authors: Kern A. , Steeb W.-H. , Stoop R. 
Published: February 2015

Abstract
We investigate local correlation dimension-based noise-cleaning of time series, where points having anomalously large dimensions are iteratively removed from the reconstructed attractor. We find an optimal range for the number of iterations in which the algorithm yields good results. Choosing non-local ranges for the linear regression yields a new method for finding nonhyperbolic tangency points. The method is also applicable for noisy systems with unknown dynamics; in this case, noise facilitates the detection of the points.
Nuclear Quadrupole Interactions in Cadmium Complexes: Semiempirical and ab initio Calculations
Authors: Hemmingsen Lars , Ryde Ulf , Bauer Rogert 
Published: February 2015

Abstract
Semiempirical calculations, based on the so-called angular overlap model, have been compared with ab initio methods (MP2) for the calculation of nuclear quadrupole interactions (NQI’s) in cadmium complexes with biologically relevant ligands (H2O, OH-, cysteinate, carboxylate, and imidazole). The assumptions on which the semiempirical model is based have been tested and the comparison indicates that: 1) A change in the Cd-ligand bond length by 0.1 A may change the electric field gradient (EFG) by about 0.2 a. u.. A simple scheme to incorporate such effects in the semiempirical method is suggested. 2) The effect of ligand-ligand interactions is up to about 0.2 a. u. for the largest diagonal element of the EFG tensor for the tested complexes, and such effects can significantly influence the so-called asymmetry parameter. 3) The position of non-coordinating atoms on the ligands can in some cases (e. g. the hydrogen atoms of water) significantly influence the EFG. The combined effect of non-coordinating atoms and ligand-ligand interactions may cause deviations of up to 0.35 a.u. between ab initio and the semiempirical calculations. 4) In the semiempirical model each ligand is characterised by one parameter, the so-called partial nuclear quadrupole interaction. This parameter has been evaluated by ab initio calculations, and agreement was found within about 0.2 a. u. (≈ 40 Mrad/s) for all ligands except imidazole. 5) A change in the coordination number from 2 to 6 may change the partial NQI by about 0.3 a. u.
The Physical and Molecular Properties of New Low Melting Nematics with Negative Dielectric Anisotropy
Authors: Dąbrowski R. , Jadżyna J. , Dziaduszek J. , Stolarz Z. , Czechowski G. , Kasprzyk M. 
Published: February 2015

Abstract
The paper presents some basic physical properties (static electric permittivities, refraction indices, density and viscosity) of 2-chloro-4-n’-alkylphenyl esters of 4-n-alkylbicyclo[2,2,2] octane-1-carboxylic acids (n’=7, n = 5 and 7) which are, at room temperature, nematics with a negative dielectric an-isotropy. On the basis of temperature dependence of the principal static permittivities ε‖(T) and e⊥(T) of the nematics, using the Maier-Meier equations, the angle between the dipole moment vector and the long axis of mesogenic molecules, the apparent molecular dipole moment square pl μ2
app(T), and the nematic order parameter S(T) were determined.
On Diffusion in Some Biological and Economic Systems
Authors: Ahmed E. , Hassanb S. Z. 
Published: February 2015

Abstract
It is argued that diffusion in biological and economical systems is better modelled by Cattaneo's equation where memory effects are included. Reaction diffusion equations using Cattaneo's system are derived for prisoner's dilemma (PD) and hawk-dove (HD) games. Nonlinear wave solutions are derived for them. As expected the asymptotic solution for the PD case is insufficient. Hence a cellular automata motivated by Cattaneo's system is used to show the existence of cooperation in the case of local game.
Observation of Carbonyl Fluoride, Ketene, Acetic Acid and Fluorocarbene Produced by an Electric Discharge within a Nozzle by Molecular Beam Fourier Transform Microwave Spectroscopy. A Reaction via a Cycloaddition for Carbonyl Fluoride and Keten?
Authors: Sutter D. H. , Dreizler H. 
Published: February 2015

Abstract
A molecular beam Fourier transform microwave spectrometer, designed for the study of chemical reactions within electrical discharges, is described in detail. Applications include the production of carbonyl fluoride, ketene, acetic acid, and difluorocarbene. For the production of carbonyl fluoride and ketene with 1,1-difluoroethylene and carbon dioxide as precursor molecules a reaction path via a 2+2 cycloaddition is proposed.