bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural Study of Amorphous Co-Ferrite Film by Anomalous X-Ray Scattering
Authors: Matsubara E. , Okuda K. , Waseda Y. , Okuno S. N. , Inomata K. 
Published: February 2015

Abstract
The structure of amorphous Co-ferrite film grown on a glass substrate was studied by anomalous X-ray scattering (AXS). Co atoms cannot be distinguished from Fe atoms with the usual X-ray diffraction technique. Therefore the AXS method at the Fe and Co K-absorption edges was adopted. In the previous AXS studies only the lower energy side of the absorption edges was adopted. In the previous AXS studies only the lower energy side of the absorption edge was used. In the present case, the lower energy side of the Co K-absorption edge corresponds to the higher energy side of the Fe K-absorption edge. Therefore, in order to overcome this inconvenience, the scattering was measured on both sides of the absorption edge, thus enabling the independent determination of the oxygen coordination numbers around Co and Fe in the ferrite film from the environmental RDFs estimated from the energy differential profiles by coupling with the linear least squares technique.
Cross-Section for Proton Transfer from a Large Peptide Ion to Ammonia in the Gas Phase
Authors: Davis Stephen C. , Derrick Peter J. , Ottinger Christoph 
Published: February 2015

Abstract
Proton transfer between ions of the cyclic peptide valinomycin (relative molecular mass 1110.6) and ammonia molecules has been studied over a range of ion energies from 50 eV to 8 keV. Valinomycin ions were produced by field desorption. Collisions of valinomycin ions with ammonia molecules at controlled energies were carried out using an ion-optical lens system situated in the source region of a large research mass spectrometer. The maximum cross-section for proton transfer occurred when the valinomycin ion possessed 1500 eV of kinetic energy. This maximum cross-sec-tion for proton transfer was 3 orders of magnitude smaller than the cross-section for collision-in-duced dissociation of the valinomycin ion at the same ion energy (2.4 • 10-17 cm2 molecule-1 as compared to 2 • 10-14 cm2 molecule-1). A stereospecific stripping model can explain the observa-tions.
Millimeter Wave Spectrum and Centrifugal Distortion Analysis of Difluorochloromethane CHF2Cl in the Ground State
Authors: Spiehl R. , Guarnieri A. 
Published: February 2015

Abstract
The rotational spectra of CHF2
35Cl and CHF2
37Cl (CFC22) in the vibrational ground state between 42 and 214 GHz are reported. A centrifugal distortion analysis up to the sixth order is carried out.
A Highly Disordered New Solid Phase Containing Isotropically Reorienting Cations in (CH3NH3 )2CdBr4 Studied by 1H NMR and Thermal Measurements
Authors: Ishida Hiroyuki , Takagi Kentaro , Terashima Mifune , Nakamura Daiyu 
Published: February 2015

Abstract
The 1H spin-lattice relaxation time, linewidth, second moment of 1H NMR absorption, differen-tial thermal analysis, and differential scanning calorimetry of methylammonium tetrabromocado-mate(II) crystals were studied. A new solid phase was found between 482 K and the melting point (493 K). The 1H NMR measurements revealed the presence of overall reorientation of methyl-ammonium cations in this phase. In the room temperature phase, 120° reorientational jumps of the CH3 and NH3
+ groups were detected.
A Theoretical Analysis of the Contributions to the Internal Rotation Barrier in N-Benzylideneanilines
Authors: Figueroa K. , Campos-Vallette M. , Contreras R. R. 
Published: February 2015

Abstract
An analysis, using CNDO wave functions, has been carried out on the different contributions to the internal rotation barrier in N-benzylideneaniline (1) and p-dimethylaminobenzylidene-p-nitro-aniline (2) in several conformations. The stability of the different structures has been expressed in terms of a partition of the total energy into electronic, net charges and steric hindrance contributions. Based on the shape of the total energy surface it appears that the barrier composition may be reasonably well described without approaching the absolute minimum. Rotation of the aniline group in both molecules is mainly governed by steric hindrance. Rotation of the benzylidene group shows a prevalent destabilizing electronic effect. The donor strength of the substituent in the benzylidene ring seems to play an important role in stabilizing a less nonplanar structure.
Calculation of Energy Characteristics of Point Defects in bcc Iron by Molecular Dynamic Technique
Authors: Melker A. I. , Mizandrontzev D. B. , Sirotinkin V. V. 
Published: February 2015

Abstract
The influence of the calculation procedure on the energy characteristics of vacancies and helium impurities in α-iron is considered. Calculations are performed with the help of long-range oscillating interatomic pair potentials found on the basis of a model pseudopotential approach. It is shown that for improving the convergence of the lattice sums one must introduce space windows. The best results were obtained with the Vashista-Singwi local-field correction and the modified windowmodulation interatomic potential based on the Heine-Abarenkov pseudopotential with the Animalu formfactors
An 1H NMR Study on the Cationic Motion in Solid tert-Butylammonium Chloride and Bromide
Authors: Ishida Hiroyuki , Inada Syuichi , Hayama Naomi , Nakamura Daiyu , Ikeda Ryuichi 
Published: February 2015

Abstract
The 1H spin-lattice relaxation time (T1) in solid (CD3)3CNH3Cl and (CD3)3CNH3Br was measured above room temperature and the motional parameters for the reorientation of the NH3
+ groups were determined. The 1H NMR absorptions measured in the same temperature range for (CH3)3CNH3Cl and (CH3)3CNH3Br indicate the presence of superimposed several cationic motions commonly taking place in both compounds. From X-ray powder patterns taken at room temperature, the bromide was found to be isomorphous with the chloride
Structural and Defect Study of Naß''-Gallatc by X-Ray Powder Diffraction Analysis
Authors: Massarotti V. , Capsoni D. , Marini A. , Berbenni V. , Flor G. , Margheritis C. 
Published: February 2015

Abstract
The Rietveld profile refinement has been applied to X-ray powder diffraction data on Naß''-gallate, a solid electrolyte isostructural with Naß''-alumina and characterized by different types of lattice defect. Several structural models have been refined and discussed in order to understand if a statistical comparison of the structure discrepancy factors can be used as a reliable criterion to retain or reject structural changes from one model to the other. It is shown that, due to the correlation between structural parameters and to the poor sensitivity of the structure discrepancy factors to chemical composition, some care is necessary to direct correctly the refinement and to obtain a reliable structural model
Space-time Transformations in Ether Theories
Authors: Selleri F. 
Published: February 2015

Abstract
By assuming the validity of the principle of inertia and the existence of a privileged frame, the transformation laws (TL) between inertial frames are investigated in ether theories. For onedimensional space the TL's are fixed up to two undetermined functions of absolute velocity, Δ (v) and E(v). If the principle of relativity is finally assumed, these functions acquire their well known Lorentzian expressions ΔL and EL. It is concluded that special relativity theory is "unstable", in the sense that any shift, however small, of Δ away from ΔL and/or of E away from EL leads to an ether theory. In Earth-based experiments one can expect deviations from c of the two-way and one-way velocity of light of the order of 10-12 and 10 -9 respectively
Monte Carlo Simulations of Water under Supercritical Conditions. I. Thermodynamic and Structural
Authors: Kalinichev A. G. 
Published: February 2015

Abstract
The thermodynamic and structural properties of water along two supercritical isotherms at 673 and 773 K in the pressure range from 0.3 to 30 kbar have been studied by the NPT-ensemble Monte Carlo method using a TIP4P intermolecular pair potential. Simulated values of the configurational enthalpy, molar volume, isobaric heat capacity, isothermal compressibility, and thermal expansion coefficient are found to be in a rather good agreement with experimental data, although the critical point of the TIP4P water model is supposed to lie about 50 degrees lower than observed experimentally. The analysis of simulated atom-atom radial distribution functions as well as the dimerization energy distributions clearly shows that hydrogen bonding persists under the conditions studied, despite the fact that the water structure may be considered as "argon-like" in terms of oxygen-oxygen distribution functions (i.e. close to that of a simple liquid)
A Microwave Fourier Transform Spectrometer in the Range from 18 to 26.4 GHz Increased Sensitivity Using Circular Waveguides. Measurements of Isotopomeres of Carbonylsulfide and of Methane
Authors: Meyer V. , Jäger W. , Schwarz R. , Dreizler H. 
Published: February 2015

Abstract
We present a microwave Fourier transform spectrometer in the region of 18 to 26.4 GHz with an increase in sensitivity roughly by a factor of ten in comparison to a former set up. Measurements of rotational transitions of isotopomers of carbonylsulfide, OCS, in natural abundance and of rovibrational transitions of methane, CH4, illustrate the improvement
Paramagnetic Defects in Benitoite
Authors: Vassilikou-Dova A. B. , Eftaxias K. 
Published: February 2015

Abstract
In clear, blue, transparent bipyramidal crystals of the rare mineral benitoite, BaTiSi3O9, para­ magnetic defects have been investigated by electron paramagnetic resonance at room temperature and 9.43 GHz. They are attributed to Sn3+ and Fe3+ . A pair of satellites recorded for a wide angular rage around B0 || c (~40°) and a relative intensity of ~ 13% to the central signal is most likely due to hyperfine interaction with 117Sn and 119Sn isotopes. Attempts to bleach the colour of the crystal were unsuccessful.
Specific Interactions of CH2
- and CH3-Groups of n-Paraffins with PFTB
Authors: Luck Werner A. P. , Peil Stephan 
Published: February 2015

The OH stretching frequency νOH of perfluoro-tert.-butanol (PFTB) dissolved in different liquid n-paraffins decreases with increasing chain length n of the solvent. This observation is explained by an overlapping of two different vOH absorption bands induced by interactions between CH2- resp. CHj-groups and the OH-oscillators of PFTB. The decrease of vOH demonstrates an increase of the intermolecular interaction energies. These mean interaction energies between the OH-groups and the solvent molecules increase with n in a similar way as the densities q of the paraffins. The frequency shifts zh'OH (^vOH = vOH(Gas, -vOH) of PFTB as well as the specific volumes V of the paraffins can be described by a sum of CH2- and CH3-group contributions. In this way the role of the cohesion energy for zlvOH is demonstrated. The OH ··· CH2-interaction has been found as 2.5 times larger than OH ··· CH3-interactions. The I ··· CH2 Lennard-Jones parameter £ has been found too as 2.5 times larger than the value of I ··· CH3 interactions. This agreement demonstrates the efficiency of the intermolecular IR spectroscopy.
The sum of group contributions for interactions of linear molecules seems to have some advan- tages and may be more intuitive by its simplicity in comparison to explanations with parameter for “non-central forces” as e.g. the acentric factors ω of Pitzer et al.
Geometric Formulation of Gauge Theories
Authors: Drechsler W. 
Published: February 2015

Abstract
The development of gauge theories is reviewed beginning with Weyl's theory of 1918 and with the changes introduced by London in the context of quantum mechanics. After a discussion of the Yang-Mills theory and Utiyama's work in the fifties the translation to the modern geometric formulation of gauge theories in terms of fiber bundles is presented
The Occurrence of a Finite Number of Particle Families in the Planck Aether Model of a Unified Field Theory
Authors: Winterberg F. 
Published: February 2015

Abstract
The Planck aether substratum model explains Dirac spinors as excitons made up from vortex resonances of the positive and negative mass substratum. In the framework of this model it is conjectured that the higher particle families arise from excited states due to radial oscillations. The characteristic feature of quantum mechanics involving negative masses leads to a finite number of such excited states. Without the knowledge of the mass distribution in the excitons, a maximum number of four families can be predicted from the known mass spectrum of the leptons. Finally, it is conjectured that the small neutrino-electron mass ratio results from a compensating gravimagnetic effect, leading to a value for this ratio equal to (m(GUT)/m (Planck))2
Stability Properties of Nonlinear Delay Systems and the Breakdown of the Adiabatic Approximation
Authors: Hawdon Brendan J. , O'Gorman James , Heffernan Daniel M. 
Published: February 2015

Abstract
We consider the adiabatic approximation as it is applied to a familiar class of infinite-dimensional equations. We show how this approximation may be directly invalidated by analyzing a statistical form of the eigenvalue equation before and after the adiabatic approximation is made. We introduce a statistical quantity which can be used to predict the existence of periodic windows in the chaotic regime
Surface Induced Spin-Lattice Relaxation of Water in Tricalcium Silicate Gels
Authors: Milia F. , Bakopoulos Y. , Miljkovic Lj. 
Published: February 2015

Abstract
The water proton spin-lattice relaxation time and recovery function of exchangeable water was measured in tricalcium silicate (C3S) gels. The measurements were carried out as a function of the hydration time and grain size. Results show that the hydration of (C3S) is a two stage process. A model is developped
Fluorescence Quantum Yields of 2-Substituted 3-Methylquinoxalines in Liquid Solutions at Room Temperature
Authors: Kawski A. , Nowaczyk K. , Kuklinski B. 
Published: February 2015

Abstract
A sensitivity modulation method was employed to measure the fluorescence spectra and quantum yields of weakly fluorescent 2-substituted (NH2, O, OCH3, CI, Br) 3-methylquinoxalines in n-hexane and methanol at room temperature. A strong decrease in the quantum yield with increasing atomic weight of the substituents was observed in n-hexane. In polar solvents, the CI substituent is the strongest quencher although its atomic weight is 2.254 times smaller than that of Br
The Effect of Oxygen on the Fluorescence Quenching of Polycyclic Aromatic Hydrocarbons in Two- Component Mixtures of CCl4 with Cyclohexane, Benzene and Acetonitrile
Authors: Chojnowski Andrzej , Wiczk Wieslaw M. , Latowski Tadeusz 
Published: February 2015

Abstract
Fluorescence quenching of anthracene and perylene has been studied in deoxygenated and nondeoxygenated two-component mixtures of CCl4 with cyclohexane, benzene and acetonitrile. It was indicate that the dissolved oxygen only reduces the fluorescence lifetimes of the hydrocarbons, thus suppressing the efficiency of quenching
The Centrifugally Induced Pure Rotational Spectrum and the Structure of Sulfur Trioxide. A Microwave Fourier Transform Study of a Nonpolar Molecule
Authors: Meyer Volker , Sutter Dieter Hermann , Dreizler Helmut 
Published: February 2015

Abstract
The pure rotational spectrum of sulfur trioxide has been observed for the first time. A total of 25 high-J transitions could be assigned. The rotational constants, two quartic centrifugal distortion constants, and three sextic centrifugal distortion constants were determined as: B= 10 449.0667(23) MHz, C = 5216.0330(12) MHz, DJ = 9.2651 (18) kHz, DJK = -16.3922(18) kHz, HJ, = -8.8(34) • 10-3 Hz, HJK= -15.8(73) • 10-3 Hz, and HKJ = 34.2(73) • 10-3 Hz. An r0- and an re -structure are presented: r0= 1.4198(7) Å (calculated from B), r0 = 1.4210(7) Å (calculated from C), and re = 1.4175 Å
Photochemical and Photophysical Properties of 4- Acyl [2.2] paracyclophanes
Authors: Hopf Henning , Laue Thomas , Zander Maximilian 
Published: February 2015

Abstract
Photochemical and photophysical properties of 4-benzoyl[2.2]paracyclophane (3) and 4-acetyl[ 2.2]paracyclophane (5) have been studied. In contrast to benzophenone and acetophenone, respectively, the lowest triplet state of 3 and 5 is of the τ, τ*-type. 3 is photochemically reactive. Photoenolization (in solution at lower temperature) is the main reaction pathway while bond fission of an exocyclic C-C bond of the formed photoenol leading to an alkylated open-chain benzophenone derivative takes place to a minor degree. Photoenolization of 3 is the first example of this type of photochemical reaction observed with a cyclophane compound, and at the same time is a novel example of the violation of Bredt's rule. Under certain experimental conditions 3 and 5 may be usable as chiral triplet sensitizers in photochemical reactions
Neutron Diffraction Studies of Structure in Aqueous Solutions of Urea and Tetramethylammonium Chloride and in Methanol
Authors: Turner J. , Finney J. L. , Soper A. K. 
Published: February 2015

Abstract
Neutron diffraction measurements on aqueous 2-14 molal urea solutions have been made using nitrogen isotope substitution on the urea and hydrogen isotope substitution on the water. In addition, the hydration region of the tetramethylammonium ion in 2.0 m urea solution has been investigated by nitrogen isotope substitution on the TMA at 0.5 m and 2.0 m concentration of TMAC1. The N-water correlation functions are very similar across the concentration range, and the H-H correlation function in concentrated urea solution is little changed from that of pure water. In the TM AC1 solutions the hydration peak is unchanged by the addition of 2.0 m urea. Thus urea appears to fit into the water network without causing significant perturbation of the average water structure or of the hydration region of another solute. In addition to the study of urea we have also made preliminary measurements to test the feasibility of carbon isotope substitution in liquid methanol.
Molecular Dynamics Study of Molten Lithium Iodide
Authors: Itoh S. , Konagai M. , Takahashi K. 
Published: February 2015

Abstract
The structural and dynamic properties of molten lithium iodide are investigated at two pressures (334 MPa at 784 K and 1054 MPa at 915 K), using molecular dynamics simulations with Born- Mayer-Huggins type pair potentials. On increasing the pressure, the local packing of the ions changes from tetrahedral to octahedral, the self-exchange velocity in the coordination shells decreases by a factor of 0.031, DLi by a factor of 0.033 and D1 by a factor of 0.021.
Conductivities of Binary Molten Alkalihalide/Silverhalide Mixtures
Authors: Boßmann H.-P. , Richter J. , Struck N. 
Published: February 2015

Abstract
The electric conductivities of molten (Na, Ag)Cl, (Rb.Ag)Cl, (Na,Ag)Br, (Rb. Ag)Br, and (Cs, Ag)Br are determined as functions of composition and temperature from the melting point to 1100 K. The relation of the temperature coefficients to the phase diagram of the systems (K.Ag)Cl, (Rb. Ag)Cl, (Cs, Ag)Cl, and (Cs, Ag)I near and at the phase transition (liquid-solid) is studied. The molar conductivities and mobilities of the cations with reference to the common anion are evaluated.
Molecular Polarizabilities and Orientational Ordering of Two Mesogens
Authors: Mitra M. , Paul S. , Paul R. 
Published: February 2015

Abstract
The refractive indices (no, ne) and densities of two mesogens have been measured in their liquid crystalline and liquid phases. The molecular polarizabilities (xo, xe) were evaluated by Vuks' and Neugebauer's relations. The polarizabilities thus obtained are compared with those estimated from the bond polarizabilities, and the orientational order parameters, <P2>, are compared with the mean field theory of Maier and Saupe, the modified mean field theory of Humphries, James and Luckhurst. and the continuum theory suggested by T. E. Faber. We have also calculated the three order parameters (<P2), τ, σ) describing the smectic A phase following McMillan's model. Possible causes of the discrepancy are discussed.
Structure and Dynamics of NaCl in Methanol. A Molecular Dynamics Study
Authors: Marx D. , Heinzinger K. , Pálinkás G. , Bakó I. 
Published: February 2015

Abstract
A recently developed flexible three-site model for methanol was employed to perform a Molecular Dynamics simulation of a 0.6 molal NaCl solution. The ion-methanol and ion-ion potential functions were derived from ab initio calculations. The structural properties of the solution are discussed on the basis of radial and angular distribution functions, the orientation of the methanol molecules, and their geometrical arrangement in the solvation shells of the ions. The dynamical properties of the solution - like self-diffusion coefficients, hindered translations, librations, and internal vibrations of the methanol molecules - are calculated from various autocorrelation functions.
Boron and Nitrogen Hyperfine Structure in the Rotational Spectrum of Aminodifluoroborane
Authors: Vormann  , Dreizler Helmut 
Published: February 2015

Abstract
The boron and nitrogen hyperfine structure in the rotational spectra of aminodifluoroborane has been investigated and the quadrupole coupling constants of 11B and nitrogen have been determined. We get the following results for the nuclear quadrupole coupling constants: Χaa(11B) = - 1.971 (6) MHz, Xbb(11B) = 0.500(11) MHz, Xcc(11B) - 2.471 (11) MHz, and Xaa(14N) = 0.890 (5) MHz, Xbb(14N) = 2.303 (7) MHz, Xcc(14N) = - 3.193 (8) MHz. Additionally we determined rotational and centrifugal distortion constants according to Watson's A reduction.
A Molecular Beam Microwave Fourier Transform (MB-MWFT) Spectrometer with an Electric Discharge Nozzle
Authors: Grabow J.-U. , Heineking N. , Stahl W. 
Published: February 2015

Abstract
We report on first experiments with our pulsed molecular beam microwave Fourier transform (MB-MWFT) spectrometer using a special nozzle which allows high voltage discharges within the nozzle orifice. Under these conditions we observed low J rotational transitions in highly excited vibrational states of carbonyl sulfide and sulfur dioxide, and also rotational lines of the SO radical in the 3Σ- electronic ground state and both the vibrational ground and first excited state.
Canonical Quantization of the Classical Hamiltonian for a Relativistic Spin-0 Particle
Authors: Briegel H.-J. , Englert B.-G. , Süssmann G. 
Published: February 2015

Abstract
When quantizing the classical Hamiltonian H (q,p,t) = [m2c4 + (c p - e A(t,q))2]1/2 + e V(t, q), commutators of the form [f (a), g(b)], where [a,b] is not a c-number, have to be evaluated. The concept of continuously symmetrized products enables us to derive a number of statements, such as a continuity equation for the density operator δ{q(t)-x)=n(t, x), in a formally concise way. We can also show, then, that the dependence of the Hamiltonian on higher powers of the kinetic momentum destroys the relativistic invariance of the theory, even if we admit a more general coupling of the external potentials than above.
X-ray Diffraction Study of Amorphous NixZr(100-x)-Alloys Prepared by Melt-Spinning
Authors: Kuschke W.-M. , Lamparter P. , Steeb S. 
Published: February 2015

Abstract
Amorphous Ni-Zr-alloys can be prepared by melt-spinning within a wide range of composition. Studies by X-ray diffraction yielded structure factors, pair correlation functions, total coordination numbers and atomic distances in dependence on the nickel concentration in the range of 25 up to 45 atomic percent. The change of the total coordination number and atomic distances turned out to be linear with the composition in this range. This is in good agreement with the linear composition dependence of the superconducting transition temperature, magnetic susceptibility, crystallization temperature, and electrical resistivity in the investigated range of composition.