bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solvation of Ions in Aqueous Solutions of Hydrophobic Solutes
Authors: Hawlicka Ewa , Grabowski Roman 
Published: February 2015

Abstract
The self-diffusion of Na+, Et4N+ and I- in mixtures of water with n-propanol at 25 °C and with lert-butanol at 30 °C was measured as function of salt concentration and solvent composition. The limiting self-diffusion coefficients of the ions were used to compute the ionic radii. The influence of the composition of the solvent on the solvation of the ions is discussed. In aqueous solutions of both alcohols the effective ionic radii are reduced. The strongest influence is found for the same solvent composition for which the highest concentration of the alcohol clusters has been reported. Hydra-tion of the clusters of n-propanol causes a vanishing of the second hydration shell of Na+ and the first one of Et4N+ and I-. In the case of terf-butanol even the first hydration shell of Na+ is partially reduced.
The Physical Interpretation of Special Relativity -a Vindication of Hendrik Lorentz
Authors: Prokhovnik S. J. 
Published: February 2015

Abstract
Modern astronomy has revealed the existence of a cosmologically-based fundamental reference frame associated with the distribution of matter in our universe. The existence of such a frame offers a firm basis to H. A. Lorentz's approach to the understanding of the relativistic effects associated with the transformation named after him.
Lorentz's approach and his notion of an "ether" evolved over a number of years, and it has been further refined as a result of our new view of the universe. It now provides a complete interpretation of Special Relativity based on a single assumption -that light-propagation takes place with respect to a unique, observable, fundamental reference frame. This interpretation links Einstein's theory with Lorentz's findings and so further develops our understanding of it; it also offers new insights for the better understanding of quantum and particle physics.
Inverse Isotope Effect on the Melting Temperature of LiNO3
Authors: Hidaka Takehiko , Lundén Arnold 
Published: February 2015

Abstract
An inverse isotope effect on the melting temperature, Tm, of lithium nitrate has been observed: Tm

is by 0.7 °C higher for a sample with 98.6% 6Li than for one with 92.6% 7Li. The abnormal sign of
the isotope effect on Tm has already previously been found in fractionation experiments. Our results
are in agreement with Holmberg’s finding for Tm of LiNO3 · 3H20 (30 °C) that the isotope effect is
inverse for 6Li- 7Li but normal for H-D. Different types of experimental methods have been compared
also for lithium sulfate, where a normal isotope effect has been found for both Tm (860 °C) and
Tc (577 °C), the temperature of a monoclinic-cubic phase transition. Otherwise, nonhydrogen isotope
effects at solid-solid transitions are usually inverse for displacive transitions, or nearly zero for
order-disorder transitions.
Graph-Theoretical Enumeration of Conjugated Patterns for Carbocyclic and Heterocyclic Compounds*
Authors: Morikawa Tetsuo 
Published: February 2015

Abstract
An algorithmic analysis of the existence of conjugated patterns for carbocyclic and heterocyclic compounds is presented. This graph theoretical method is applicable to the enumeration of Kekulé patterns for hydrocarbon benzenoids, as a special case.
Spectral Properties of Some Naphthalene Derivatives of Bicarboxylic Acid; Comparison of Experimental Results with Theoretical Predictions
Authors: Bauman Danuta , Hanemann Thomas , Wolarz Eryk 
Published: February 2015

Abstract
The basic electronic quantities of some dichroic dyes, naphthalene derivatives of bicarboxylic acid, have been evaluated theoretically using a semi-empirical INDO (intermediate neglect of differential overlap) Cl (configuration interaction) approach. The theoretical data have been com­ pared with the experimental results obtained from the absorption and fluorescence measurements of the dyes dissolved in toluene and oriented in liquid crystal 8CB. Additionally, the order parame­ ters of the dyes in smectic A and nematic phases of 8CB have been determined.
Synthesis and Microwave Spectroscopic Study of Fluorinated Methyl Isocyanides
Authors: Krüger M. , Dreizler H. , Lentz D. , Preugschat D. 
Published: February 2015

Abstract
Difluoromethyl isocyanide has been generated by flash vacuum pyrolysis of pentacarbonyl (di-fluoromethyl isocyanide) chromium at 240 °C. Spectroscopic studies revealed the presence of several major and minor impurities like HCN, HCC -CN and HCC -NC . The pyrolysis of pentacarbonyl (fluoromethyl isocyanide)chromium did not lead to the observation of free fluoromethyl isocyanide. The rotational spectrum of difluoromethyl isocyanide has been recorded with a conventional continuous wave Stark spectrometer and a molecular beam Fourier transform microwave spectrometer resulting in A = 10.110841 (42), B = 4.550914 (19), C = 3.343550 (19) GHz, D′J = 0.41(13), D′JK = 26.72(36), D′J
= - 21.3 (18) kHz. The dipole moment components μa = 1.46(1), μc= 1.83 (1) and μtotal 2.34 (1) D were obtained from the second order Stark effect. The 14N nuclear quadrupole hyperfine structure in the rotational spectrum of CHF2-NC has been resolved and the 14N nuclear quadrupole coupling constants xaa = 599.0 (10), xbb = −406.5 (14), xcc= −192.6 (14) kHz have been obtained.
An EXAFS Investigation of Local Structure around Rb+ in Aqueous Solution
Authors: Kubozono Yoshihiro , Hirano Akiko , Maeda Hironobu , Kashino Setsuo , Emura Shuichi , Ishida Hiroyuki 
Published: February 2015

Abstract
EXAFS spectra have been measured in order to elucidate the local structure around Rb+ in aqueous solution. It has been found that the Rb+ is surrounded by ca. six O atoms of H2O molecules. The Rb -O distance was determined to be 2.90 (3) Å. The coordination number and Rb -O distance compare well with those of the other alkaline metal ions estimated by X-ray diffraction.
Notiz: A Molecular Source of CF2(X̃) at Room Temperature
Authors: Hack W. , Wagner M. 
Published: February 2015

Abstract
In the molecular system of F2 and C3O2 a fast formation of CF2 (X̃) was detected directly via LIF. The CF2 (X̃) production mechanism could be a single step process but also how­ ever a chain reaction via F atoms.
Transition to Higher Chaos in Diffusively Coupled Chemical Oscillators
Authors: Baier Gerold , Sahle Sven , Kummer Ursula , Brock Roland 
Published: February 2015

Abstract
A one-dimensional array of diffusively coupled identical oscillators is considered. It is demon­strated that coupling of two, three, four, and six oscillators can create chaos with one, two, three, and four positive Lyapunov characteristic exponents, respectively. We suggest that the turbulent behavior found with many coupled cells can be explained in terms of a high-order chaotic attractor.
The Velocity of Current Filaments in Weak Magnetic Fields
Authors: Christen Thomas 
Published: February 2015

Abstract
In the presence of a perpendicular weak magnetic field, current filaments in semiconductors can obtain a transverse drift. In the framework of a collective-coordinate ansatz, an expression for the velocity of the filament is derived for a simple type of extrinsic semiconductors. It turns out that the motion is caused by the coupling of the non-uniform Hall angle to the translational Goldstone mode of the current filament.
Universality in the One-Dimensional Self-Organized Critical Forest-Fire Model
Authors: Drossel Barbara , Clar Siegfried , Schwabl Franz 
Published: February 2015

Abstract
We modify the rules of the self-organized critical forest-fire model in one dimension by allowing the fire to jum p over holes of ≤ k sites. An analytic calculation shows that not only the size distribution of forest clusters but also the size distribution of fires is characterized by the same critical exponent as in the nearest-neighbor model, i.e. the critical behavior of the model is universal. Computer simulations confirm the analytic results.
Similarity Solutions of the Force-free Magnetic Field Equations
Authors: Richter E. W. 
Published: February 2015

Abstract
Force-free magnetic fields are described as solutions of special nonlinear partial differential equations which are replaced frequently through linear equations. To record the diversity of the structures of these fields, a discussion of the nonlinear equations is necessary. For this purpose the method of similarity analysis is used. The Lie symmetry groups admitted by the nonlinear equations for force-free magnetic fields are presented. To record and classify the different types of group-invariant solutions, one-and two-dimensional optimal systems of subalgebras are listed. The reduced equations of the two-dimensional optimal system are systems of ordinary differential equations, and their solutions define similarity solutions which are force-free magnetic fields. Only in one case is it necessary to calculate similarity solutions numerically. The corresponding reduced equations are a nonautonomous dynamical system with the similarity variable in the place of time.
Solomon Echoes Extended to Soft Pulse Excitation
Authors: Man Pascal P. 
Published: February 2015

Abstract
Solomon echoes, produced by two in-phase pulses separated by a delay τ2, are derived in taking into account the first-order quadrupolar interaction during the pulses. Consequently, the results are valid for any ratio of the quadrupolar coupling, ωQ, to the amplitude of the radiofrequency pulse, ωRF. Six echoes are predicted after the second pulse: three, detected as inner satellite signals, occur at τ4 = τ2, τ4 =2 τ2 and τ4 = 3 τ2/2; the other three, detected as outer satellite signals, occur at τ4=τ2/2, τ4 =τ2 , and τ4=3τ2/2. These echoes originate from the refocusing of single- and multi-quantum offresonance coherences developed during the first pulse. Four of them are allowed echoes, the other two are forbidden ones. However, there is no echo for the central transition. From a practical point of view this means that τ2 must be short compared to τFID, the duration of the FID of the central transition. The behavior of the echo amplitude versus the second pulse length is discussed for several ratios of ωQ/ωRF.
Calculation of Quadrupole Coupling Constants: From Gas to Liquid
Authors: Huber Hanspeter 
Published: February 2015

Abstract
Nuclear quadrupole coupling constants for D, 14N and 17O calculated with basis sets of high local quality are reviewed. It is confirmed that the concept of high local quality gives reliable results for many molecules in the gas phase. The calculations are extended to the condensed phase by combining quantum chemical calculations with molecular dynamics simulations. An excellent agree­ment with experiment is obtained for the deuterium coupling in liquid D2O and a fair agreement for 17O coupling in liquid H2
17O . The 21Ne nmr relaxation time in liquid neon is calculated to be within about 20% of experimental values, an exact comparison being difficult due to only roughly known pressures in the experiment and not adequately treated quantum effects in the simulations. Comparisons in the dense supercritical region at higher temperatures would be of interest, but experimental data are lacking.
Sternheimer Factors and Electric-Field-Gradient Hyperpolarisabilities for Ions in Crystals
Authors: Fowler P. W. , Kelly H. M. 
Published: February 2015

Abstract
Analytic coupled Hartree-Fock calculations of the electric field gradient response properties y (the Sternheimer shielding factor) and e (the dipole-dipole-electric field gradient hyperpolarisability) have been carried out on anions in clusters that simulate that crystal environment. The systems studied are F- in LiF and NaF, Cl- in LiCl and NaCl, O2-in MgO, S2- in MgS, and H- in LiH. Both properties show large reductions from free-ion values and significant variation with lattice parameter, and the results indicate that damped values of anion Sternheimer factors will be necessary in accurate simulation of N Q R data or modelling of properties of ion-pairs.
35Cl NQR Spin-Lattice Relaxation Mechanism in Ni(H2O)6SnCl6 and Mg(H2O)6SnCl6 Crystals
Authors: Horiuchi Keizo 
Published: February 2015

Abstract
The 35Cl NQR spin-lattice relaxation mechanism in isomorphous Ni(H2O)6SnCl6 and Mg(H2O)6SnCl6 crystals is reported. The spin-lattice relaxation time T1Q in the Ni compound is determined mainly by a paramagnetic relaxation. However, above ca. 400 K T1Q decreased rapidly and a log vs. T1 curve was almost linear. This steep decrease of T1Q was explained by reorientational motions of the anions with an activation energy of 73 kJ mol-1. In addition, a double minimum in T1Q, which can be interpreted as arising from the fluctuation o f the electric field gradient (EFG) at the chlorine site caused by cationic thermal motions, was observed around room temper ature. The temperature dependence of the 35Cl NQR T1Q in the Mg salt is re-analysed in the light of the EFG -modulation effect caused by a 180° flip motion of the H2O molecules and an overall reorientational motion of the [Mg(H2O)6]2+ octahedral cations as a whole.
Dynamics of Deuteron Glasses as Probed by 2 D Exchange NMR
Authors: Dolinšek J. , Zalar B. , Blinc R. 
Published: February 2015

Abstract
The deuteron intra-bond dynamics o f the deuteron glass phase in Rb0. 68(ND4)0.32D2AsO4 has been studied by 2 D exchange NMR which extends the NMR observation window from the kHz region into the milli-Hertz region. The results show that the O -D···O deuterons are indeed the basic reversible two-position dipoles in the structure and that deuteron intra-bond exchange -and thus dipole reversal transition -occurs deeply in the glass phase well below Tg where 1 D NMR techniques observe only frozen static glassy disorder.
17O Quadrupole Dips in Ammonium Persulphate
Authors: Peirson N. F. , Smith J. A. S. , Stephenson D. 
Published: February 2015

Abstract
The magnetic field dependence of the 1H spin-lattice relaxation time in ammonium persulphate shows pronounced minima near the 1H magnetic resonance frequencies of 1,200 and 2,200 kHz. These are interpreted in terms of a model involving cross-relaxation between 1H in the NH4 ion and 17O in natural abundance in the S2O2-
8 ions, the latter having a much shorter spin-lattice relaxation time. A theoretical analysis of the shape of the minima is used to derive values for the 17O quadrupole parameters. This analysis results in best estimate values for the quadrupole coupling constant of 6.75 (± 0.05) MHz and an asymmetry of 0.30 (± 0.02). Such values are indicative o f O-H hydrogen bonding and suggest the S2O2-
8 ion is not undergoing rapid reorientation at temperatures below 320 K.
Temperature Dependence of Impurity Induced EFG's in Extremely Diluted CuB
Authors: Sulzer G. , Ittermann B. , Diehl E. , Fischer B. , Frank H.-P. , Jäger E. , Seelinger W. , Stockmann H.-J. , Ackermann H. 
Published: February 2015

Abstract
The temperature dependence of impurity induced EFG 's around implanted 12B ions in Cu was measured for two lattice locations using the β-NMR method. The induced EFG at the nearest neighbouring host atoms decreases with increasing temperature for the case of 12B stopped on interstitial sites, whereas the opposite temperature behaviour was found if 12B is situated in substi­tutional sites.
Systematic Investigation of MF3 Crystalline Compounds (M = Al, Cr, Fe, Ga, In, Sc, Ti, and V) and Fe1-xMxF3 Mixed Series (M = Ga, Cr, V)
Authors: Blank H.-R. , Frank M. , Geiger M. , Greneche J.-M. , Ismaier M. , Kaltenhäuser M. , Kapp R. , Kreische W. , Leblanc M. , Lossen U. , Zapf B. 
Published: February 2015

Abstract
The electric field gradient at the fluorine site of several crystalline trifluorides was measured by means of the time differential perturbed angular distribution method. The hyperfine data (vQ and η) are systematically analyzed by taking into account the structural parameters of the crystals; they are also compared to the results obtained by point charge calculations.
Dehydration of Solid SnCl2(OH2)· H2O to SnCl2
Authors: Pirnat J. , Lužnik J. , Jagličić Z. , Trontelj Z. 
Published: February 2015

Abstract
The temperature and flow rate dependence of the dehydration of SnCl2(OH2) · H2O , having a layered structure, into SnCl2 in a dry inert gas stream is studied. The experimental results obtained via chlorine NQR and weight measurements are analysed in the light of the structural transformation of this compound. The mechanism of water depletion from the layered structure is discussed.
43Ca NMR Study of Bismuth-Based High-Tc Superconductors
Authors: Trokiner A. , Le Noc L. , Yakubovskii A. , Mykhalyov K.N. , Verkhovskii S.V. 
Published: February 2015

Abstract
As a first step of a study of the electronic properties of CuO2 planes by probing calcium nuclei in the bismuth-based high-Tc materials we report here the structural assignment of Ca NMR lines measured in 43Ca-enriched samples of n = 2 ((Bi,Pb)2Sr2CaCu2O8+x) and n = 3 ((Bi,Pb)2Sr2-Ca2Cu3O10+x) bismuth compounds. Powdered samples were investigated as well as oriented pow­ ders, achieved by uniaxial alignment of the grains in a 7T magnetic field. For the main calcium site (Ca between two CuO2 planes), we could determine the quadrupolar as well as the shift tensors. The results indicate that, in the same way as yttrium nuclei in YBaCuO, calcium nuclei are sensitive to the magnetic susceptibility of the metallic CuO2 planes.
Nuclear Quadrupole Resonance Study of Copper in Electron-Irradiated YBa2Cu3O6.95
Authors: Kieninger M. , Majer G. , Seeger A. , Dworschak F. 
Published: February 2015

Abstract
NQR of Cu in YBa2Cu3O6.95 was investigated before and after low-temperature electron irradiation as well as after annealing at several distinct temperatures up to 440 K. Irradiation with 2.76 MeV electrons (fluence ϕt = 2.2 · 1023 e-/m 2) decreased the critical temperature Tc from 91.8 K to 89.5 K. The NQR spectra indicate that the e- irradiation displaces so-called 0 (4) atoms in the Cu - O chains. It is argued that this results in a modification of the average valence of the Cu(2) atoms in the planes, which explains the reduction of Tc. Recovery of the radiation damage sets in (presumably due to the onset of mobility of displaced oxygen atoms) during annealing at 300 K but was still incomplete at 440 K.
Investigation of the Phase Transition at 67.17 K in the Thiourea-CCl4 Inclusion Compound. As Studied by 14N NQR
Authors: El Ghallali J. , Gourdji M. , Guibé L. , Péneau A. 
Published: February 2015

Abstract
The 14N NQR from the host lattice of the thiourea-carbon tetrachloride inclusion compound. From calorimetric measurements, two phase transitions are known to occur at 67.2 K and 41.3 K in this compound. Above the 67.2 K transition, the 14N NQR spectrum consists of one resonance, though a small splitting of about 0.5 kHz is seen at temperatures up to ca. 105 K. Below the transition, the resonance appears as a central component, in continuation of the resonance above the transition, and two satellites at + 10 kHz and -8 kHz from the central line. The transition from the single resonance to a fully resolved spectrum takes place in a temperature range of less than one kelvin. The results are compared with those previously obtained with the thiourea-cyclohexane inclusion compound.
Positronium Quadrupole Interactions in Crystals
Authors: Bondarev I.V. , Kuten S.A. 
Published: February 2015

Abstract
It is shown that, due to the hyperfine interaction between the electron and the positron, positronium atoms in a crystal can acquire an effective quadrupole moment and a tensor polarizability. In such a case the effective quadrupolar interaction with intracrystalline fields leads to a quadrupolar splitting of the triplet level of positronium and also to an anisotropy of its magnetic quenching in the presence of an external magnetic field. The possibilities of observating this anisotropy experimentally are discussed.
Dissociation Degree of HSO-
4 and Mean Ionic Activity Coefficient of Aqueous Sulfuric Acid of Different Molalities up to 473 K and 975 bar
Authors: Bilal B. A. , Müller E. 
Published: February 2015

Abstract
The apparent formation constant and the dissociation degree of HSO-
4 in aqueous H2SO4 of the molalities 0.1, 0.5, and 1.0 m, as well as the real mean ionic coefficient have been calculated up to 473 K and 975 bar using the thermodynamic data reported by Holmes and Mesmer at saturation pressure and those given by the authors at higher pressure.
Coupled Bistable Chemical Systems - Experimental Realization of Boolean Functions Using a Simple Feedforward Net
Authors: Zeyer K.-P. , Dechert G. , Hohmann W. , Blittersdorf R. , Schneider F. W. 
Published: February 2015

Abstract
We use the BZ-reaction and the MBO-reaction to implement the Boolean functions AND, OR, NAND , and NOR by the coupling of three chemical reactors. The experimental setup is analogous to a simple neural feedforward network with two reactors serving as the input layer and one reactor as the output layer. Coupling between the input and output reactors is carried out through the flow rate (BZ- and MBO-reaction) and through the electrical current by the use of Pt working electrodes (BZ-reaction). The XOR- and XN OR functions may be realized with 5 reactors using combinations of the AND, NOR, NOR - and the AND, NOR, Or-chemical gates, respectively.
A Geometrical Model of the Structure of Liquid Silicon Incorporating the Local- and Medium-Range Orders
Authors: Ogawa Hiroshi , Waseda Yoshio 
Published: February 2015

Abstract
A new structure model of liquid silicon is tested by incorporating the local bond orientational order and the medium-range radial distribution. The shoulder observed on the high Q side of the principal peak in the structure factor of liquid silicon appears to be mainly caused by the atomic radial distribution in the range from 0.4 to 0.6 nm. On the other hand, a molecular dynamics simulation on liquid silicon shows that the angular distribution of neighboring atoms has tetrahedral-like features, similar to those in the β-tin type crystal structure with c/a = 0.7. With these facts in mind, a new geometrical model of liquid silicon is proposed which simultaneously satisfies the experimental density, radial distribution, calculated bond orientational order, and typical liquid nature of random orientation in the long range.
Statistical Mechanical Interpretation of Black Hole Entropy
Authors: Winterberg F. 
Published: February 2015

Abstract
It is shown that the Bekenstein-Hawking formula for the entropy of a black hole can be given a statistical mechanical interpretation in terms of Planck mass particles. It is furthermore shown that the previously proposed Planck aether model (assuming that space is densely filled with an equal number of positive and negative Planck masses) gives an expression for the black hole entropy, different from the Bekenstein-Hawking formula, with the entropy proportional to the 3/4 power of the black hole surface rather than proportional to its surface.
The Planck aether model also gives an expression for the entropy of the gravitational field, which for a black hole is the entropy of negative Planck masses. To be consistent with Nernst's theorem, it is conjectured that this gravitational field entropy is negative. For a universe in which the sum of the positive matter energy and the negative gravitational field energy is zero, the sum of the matter and gravitational field entropy would therefore vanish as well. Because the positive and negative Planck masses are separated from each other, a cancellation of their entropy appears to be only possible in the event of a gravitational collapse of the universe as a whole.
Konzept einer neuartigen Wärmekraftmaschine
Authors: Daniel H. 
Published: February 2015

Abstract
The Concept of a Novel Heat Engine The concept of a novel heat engine based on Knudsen-thermotransport of gas is outlined. The conversion factor is calculated. For small temperature differences its theoretical value amounts to half the Carnot value. The novel engine may turn out to be particularly suitable for using solar energy.