bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Bivalent Cations in the Adsorption of Phosphonic Acids on Iron Electrodes Studied by the Radiotracer Method
Authors: Kármán F. H. , Kálmán E. , Várallyai L. , Kónya J. 
Published: February 2015

Abstract
The adsorption of 1-hydroxyethylidene-1,1 -diphosphonic acid (HEDP) on an iron electrode in neutral aqueous solution has been examined by the radiotracer method. The role of calcium and zinc cations in the adsorption mechanism has also been studied in order to understand the synergistic effect when HEDP is applied together with these cations
Thermodynamic Theory for Binary Fluid Mixtures in the Gravitational Field
Authors: Schröer Wolffram 
Published: February 2015

Abstract
The thermodynamic theory for a fluid mixture in a gravitational field under a given pressure is developed. The local density and the local molfraction are varied to minimize the Gibbs free energy of the system. With the approximation of local thermodynamics, a set of coupled linear differential equations of first order is obtained. The non-local van der Waals-Landau contributions, leading to a set of linear differential equations of second order, are discussed for the two component lattice gas. Experimental methods allowing to determine concentration and density gradients are discussed also.
High-Resolution Vibrational Spectra of Furazan
Authors: Stiefvater Otto L. 
Published: February 2015

Abstract
The study by Fourier transform (FT) infrared (IR) spectroscopy of the fundamental vibrational bands v12 and v5 of furazan yields the origins of these bands with a statistical uncertainty of 10-6 cm-1, which leads to an estimated absolute uncertainty of 10-4 cm-1. The values are v°12 = 952.6123 cm -1 and v°5 = 1.005.3536 cm -1. They confirm the values previously deduced from laser/microwave double resonance (LMDR) experiments. Previous results for the molecular constants of the vibrational ground state and of the two vibrationally excited states, as obtained by double resonance modulation (DRM) microwave spectroscopy alone, are confirmed and refined. Advantages brought about through the combination of the DRM microwave and the FT-IR technique are outlined.
Studies of Polymer Solvation by Dielectric Relaxation Spectroscopy IV:Polyvinylpyrrolidone in Urea Derivatives at Different Temperatures
Authors: Rohmann M. , Stockhausen M. 
Published: February 2015

Abstract
The dielectric spectrum is measured up to 72 GHz of solutions of polyvinylpyrrolidone (PVP) in tetramethylurea (TMU), dimethylethylene urea and dimethylpropylene urea. Concentrations are up to a monomole fraction of 0.65 (PVP 1200) or 0.5 (PVP 40 000). Measuring temperatures are 20CC for all systems and additionally 40 and 60°C for the TMU solutions. For the description of the results a superposition of Debye type components is used, which are discussed in particular with respect to the solvent contributions. These can be distinguished into three regions: (i) Unaffected bulk-type; (ii) loosely affected, relaxation time and activation enthalpy increasing with increasing polymer content; (iii) quasi bound and moving together with the polymer. The solvation numbers (total of affected solvent per repeat unit of polymer) are about 1.5 to 2.
Kinetic Energy Release and Position of the Transition State for С6Н7
+ Ions Produced from Isomeric C7H8O Precursors
Authors: Selim Ezzat T. M. , Rabbih M. A. , Fahmey M. A. 
Published: February 2015

Abstract
The energetic requirement and mechanisms for CHO' loss from the molecular ions of isomeric C7H8O precursors have been reported. The heat of formation of [C6H7]+ (protonated benzene) was determined and ε* evaluated. Measurement of the kinetic energy release TB gives the energy-partitioning quotients q= TB/εr* which range from 0.38 to 0.99. The energy available and TB are small for the strongly endothermic reaction of benzyl alcohol but increase sharply in the case of the weakly endothermic reaction of anisole. All reactions have "late" transition states, the position X0*of the transition state on the reaction coordinate varying from 0.64 to 0.93
Dyadic Procedure for Planewave Scattering by Simply Moving, Electrically Small, Bianisotropic Spheres
Authors: Lakhtakia Akhlesh 
Published: February 2015

Abstract
A dyadic procedure is given for the planewave scattering response of an electrically small, bianisotropic sphere moving with a constant velocity in free space. Lorentz transformations and the polarizability dyadics of a stationary bianisotropic sphere are used in this procedure
Electrical Conductivity of Molten LaCl3-NaCl, LaCl3-KCl, and LaCl3-CaCl2
Authors: Fukushima K. , Iwadate Y. , Andou Y. , Kawashima T. , Mochinaga J. 
Published: February 2015

Abstract
The electrical conductivities (x's) of molten LaCl3-NaCl, LaCl3-KCl, and LaCl3-CaCl2 were measured at 893-1168 K, by a conventional ac technique and fitted by quadratic functions of temperature. They increase with increasing temperature and decrease with increasing mole fraction of LaCl3. The equivalent conductivities (A's) follow a linear relationship of In A vs. 1/T The A's of LaCl3-NaCl and LaCl3-KCl decrease drastically with increasing LaCl3 concentration. A of molten LaCl3 is smaller than that of molten CaCl2, in which the octahedral complex anion CaCl4-
6 is known to exist. It seems reasonable to assume that complex ions or cluster species such as LaCl3
6- and La2Cl3 exist in molten LaCl3 and its mixture melts. Similar results, reported in a previous paper, were obtained for PrCl3-NaCl, PrCl3-KCl, and PrCl3-CaCl2
Rotational Spectrum of Borane IMonoammoniate: Boron and Nitrogen Hyperfine Structure and Vibrational Structure
Authors: Vormann Kirsten , Dreizler Helmut 
Published: February 2015

Abstract
The boron and the nitrogen hyperfine structure in the rotational spectra of two borane monoammoniate isotopomers, 11BH3NH3 and 11BH3ND3 have been investigated and the quadrupole coupling constants of boron and nitrogen have been determined. It was also possible to determine the spin rotation constants CN of boron. In the spectrum of 11BH3NH3 we observed additional splittings which are not caused by quadrupole coupling. In the spectra of the ammonia dimer, (NH3)2, to our opinion the same kind of splittings occur. As interpretation of this phenomenon it was proposed that two different vibrational states cause the splitting. They were called ■x and ß. We use the same model for 11BH3NH3. The deuterated isotopomer 11BH3ND3 shows the normal spectrum of a symmetric top with two coupling nuclei, similar to the deuterated ammonia dimer (ND3)2. We obtained the following results: 11BH3ND3 in the x vibrational state, l/2(B + C) = 17517.21399(48) MHz, eQqaa(11B) - 2.584 (10) MHz, eQ gaa(14N) = -2.135 (5) MHz, CN(11B) = 4.59 (87) kHz, 11BH3NH3 in the ß vibrational state, 1/2(B + C) - 17517.27706 (52) MHz, eQqaa(11B) = 2.583 (8) MHz, eQqaa(14N) = -2.132 (5) MHz, CN(11B) = 4.76 (99) kHz, and 11BH3ND3, 1/2 (B + C) = 15076.79992 (41) MHz, eQqaa(11B) = 2.550 (7) MHz, eQqaa(14N) = -2.169 (4)"MHz, CN(11B) = 3.42 (67) kHz
Structure and Bonding of Tribromocadmates, ACdBr3, A = NH4, Rb, Cs, CH3NH3, (CH3)2NH2, (CH3)4N], [H2NNH3, and (H2N)3C. An X-ray Diffraction and 79-81Br NQR Study
Authors: Krishnan V. G. , Dou Shi-qi , Weiss Alarich 
Published: February 2015

Abstract
The 79-81Br NQR spectra of tribromocadmates with the cations K⊕, NH4
⊕, Rb⊕, Cs⊕, CH3NH3
⊕, (CH3)2NH2
⊕, (CH3)4N⊕, H2NNH3
⊕, and C(NH2)3
⊕ were studied as functions of temperature from 77 K on up to T>300 K. CsCdBr3 shows a singlet 81Br NQR spectrum over the whole temperature range studied. [CH3NH3]CdBr3, with one 81Br NQR line spectrum at room temperature, experiences a phase transition at 167 K; below this temperature an 18-line spectrum is observed. In [(CH3)4N]CdBr3 (phase II), at 290 K, a singlet 81Br NQR is present as is in the high temperature phase III (TII.1 , = 390 K); the low temperature phase III (TII,m, = 160 K has a triplet 81Br NQR spectrum. KCdBr3 shows an 81Br NQR doublet spectrum, as do RbCdBr3, [H2NNH3]CdBr3, and [C(NH2)3]CdBr3. 81Br NQR triplets are observed for [(CH3)2NH2]CdBr3 and NH4CdBr3. Several crystal structures were determined (at room temperature). [(CH3)4N]CdBr3: P63/m, Z = 2, a - 940 pm, c = 700 pm, disordered cation, single chain Perovskite with face connected [CdBr6]- octahedra (nearly CsNiCl3-type). [(CH3)2NH2]CdBr3: P21/c, Z = 4, a = 898 pm, 6 = 1377 pm, c = 698 pm, ß = 91.2°, face connected [CdBr3-octahedra single chain Perovskite. NH4CdBr3: Pnma, Z = 4, a = 950 pm, b = 417 pm, c= 1557 pm, with a double chain of condensed [CdBr6]-octahedra, NH4CdCl3-type. [N2H5]CdBr3: P2,/c, Z = 4, a = 395 pm, 6 = 1749 pm,c = 997 pm,ß = 94.2°, double chain polyanion similar to NH4CdBr3. [C(NH2)3]CdBr3: C2/c, Z = 4, a = 778 pm, 6 = 1598 pm, c = 746 pm, ß = 110.2°, a single chain Perovskite with a chain of condensed trigonal bipyramids [CdBr5].
Three types of anion chains of CdBr3 have been observed: Single octahedral chains, face connected; double octahedral chains, edge connected; a trigonal-bipyramidal chain, edge connected. The relation between the crystal structure and the Br NQR is discussed
Phase Transitions in the Generalized Entropy Spectrum of Nonhyperbolic Dynamical Systems
Authors: Stoop R. 
Published: February 2015

Abstract
In this contribution, the Generalized Thermodynamic Formalism is applied to a nonhyperbolic dynamical system. The associated generalized entropy function is discussed. The model considered is equipped with a generating partition of two symbols; in contrast to analogous hyperbolic models, the support of the generalized entropy function is two-dimensional. Furthermore, the phase-transition- like behavior caused by the nonhyperbolicity of the measure is shown to lead to the manifestation of a critical line in the surface described by the generalized entropy function. It is discussed how the different combinations of phase-transitions in the more specific entropy spectra fx), SG (ε) and ϕ(λ) are determined by the form of the generalized entropy function
NMR Spin-Lattice Relaxation and Tunnelling of Partially Deuterated Methyl Groups
Authors: Langen H. , Müller-Warmuth W. 
Published: February 2015

Abstract
Proton spin lattice relaxation rates have been measured at 15 and 30 MHz and down to 5 K for the partially deuterated molecular crystals 4-F-toluene, 4-Cl-toluene, and 2,6-Cl2-toluene. The behaviour of these materials is governed by methyl group tunnelling. As compared with the undeuterated compounds, the low temperature relaxation is enhanced and the details depend on the removal of the symmetry coupling between rotator and spin states. The hindering barriers remain unchanged, the A to E conversion rates are faster, and relaxation is dominated by spectral density contributions J(2ωo) and J(2ω0). In one case an additional influence of level-crossing energy transfer on relaxation is observed. Field-cycling spectroscopy reveals steps rather than peaks if the proton spin Zeeman and tunnelling splittings match
Observation of a Heteroelinie Tangeney Crisis in an NMR-Iaser System
Authors: Flepp L. , Finardi M. , Parisi J. , Holzner R. , Badii R. , Brun E. 
Published: February 2015

Abstract
Symbolic-dynamical encoding of chaotic dynamics yields a precise quantitative characterization of the temporal scaling behavior at crisis points. A complete analysis in the heteroclinic tangency case is presented for an NMR-laser
Conductance Studies of Aqueous Succinic Acid
Authors: Apelblat Alexander , Barthel Josef 
Published: February 2015

Abstract
Conductance measurements of aqueous solutions of succinic acid and of di-sodium succinate were performed from 278.15 to 308.15 K and the limiting conductances λ0 (1/2 Succ2- ) are reported. The Waiden product is independent of temperature: λ0(1/2 Succ2-)*η(T) = 0.503 ± 0.001. The salt conductances closely obey the Onsager limiting law. The evaluation of the equilibrium constants for the primary and secondary steps of dissociation, K1 and K2, and the limiting conductances of the hydrosuccinate ion, λ0(HSucc-), are discussed using the Quint and Viallard conductance equation
Luminescence Properties and Electronic Structure of Some Quinolizinone and Indolizinone Derivatives
Authors: Bakalova Sn. , Nikolov P. , Stanoeva E. , Ognyanov V. , Haimova M. 
Published: February 2015

Abstract
The absorption and luminescence static and dynamic properties of a group of quinolizinone and indolizinone derivatives in solvents of different polarity at 297 K and 77 K are studied. On the basis of the spectral data and the PPP quantum-chemical results the problem of the main chromophore in these structures is discussed
Notizen: Stability of the Liquid State of Concentrated Aqueous Solutions of Lithium Salts at Low Temperatures
Authors: Hasebe Tooru , Tanaka Kazuko , Tamamushi Reita , Sato Rie 
Published: February 2015

Abstract
The stability of the liquid state of aqueous lithium salt solutions was studied with a modified DTA technique. Aqueous solutions of LiCl and LiSCN in the concentration range 8-14 mol kg-1 , LiBr in the range 8 - 10 mol kg-1 maintain their liquid state for at least 50 hours at temperatures slightly above their glass transition points
Static and Hydrodynamic Properties of Nematic Liquid Crystals
Authors: Chrzanowska A. , Sokalski K. 
Published: February 2015

Abstract
The static properties of nematic liquid crystals are summarized. The mean field potential emerging from the static distribution function has been used to the hydrodynamic theory. Rotational viscosity coefficients have been investigated. The Parodi relation has been shown to be completely satisfied. Static and hydrodynamic properties have been predicted on the basis of one intermolecular potential
1H and 2H NMR Studies of Mixtures 2,6-Lutidine/Water Near the Lower Critical Solution Point
Authors: Balevicius Vytautas , Weiden Norbert , Weiss Alarich 
Published: February 2015

Abstract
Deuteron spin-lattice relaxation time (TJ measurements of binary mixtures 2,6-lutidine/D20 have been done near the lower critical solution point (TC, L), ε = (T - TC, L)/TC, L ≧10-5. Singularities are observed at TC, L. The changes in the slope of T1 (2H) = ƒ ( T ) can be interpreted as due to the effect of concentration changes on Ty and simultaneously strong overlaping of 2H NMR signals from coexisting phases. In the two-phase region, ca. 2°C above TC, L two D2O signals with very strong temperature evolution have been detected. Similar doubling of 2,6-lutidine 1H NMR signals has been observed already at T - TC, L ≦ 1 °C. It is shown that the two signals arise from the nuclei in two coexisting phases; they are not due to pecularities of hydrogen bond. The difference between chemical shifts of both D2O signals δ’ - δ” possess the property of an order parameter, i.e. δ’ - δ” ~ εβ with β = 0.336±0.030
Determination of the Ring-Inversion Barrier in γ-Thiobutyrolactone by Microwave Fourier Transform Spectroscopy
Authors: Harder H. , Lesarrif A. G. , Alonso J. L. , Dreizler H. , López J. C. 
Published: February 2015

Abstract
The microwave spectrum of γ-thiobutyrolactone has been reinvestigated using microwave Fourier transform spectroscopy. The μc rotation inversion transitions have been found to be splitted for the first excited state of the vibration at ~ 250 cm-1 . An inversion splitting of 0.014 MHz has been measured directly from these transitions. These splittings indicate that the vibration is related to a double minimum potential function describing two ring-twisted conformations connected by inversion. A one-dimensional reduced potential function has been derived for this vibration and gives a barrier to ring inversion of 1380± 350 cm-1.
The Kinetics and Formation of Small Carbon Clusters in an Argon Matrix
Authors: Szczepanski Jan , Pellow Robert , Vala Martin 
Published: February 2015

Abstract
Pure carbon clusters, formed by Nd/YAG laser ablation of graphite, have been trapped in an argon matrix at 12 K. The temperature dependence of the prominent infrared absorption bands attributable to C3 , C5 , C6 , and C9 clusters has been investigated between 12 K and 38 K. The former two are observed to decay and the latter two to grow with increased matrix annealing. A new kinetic model based on solid state diffusion theory and involving thermally activated diffusion and aggregation is introduced. All possible pairwise interactions of the linear carbon clusters from C1 to C10 are included in the model. The coupled differential equations are solved numerically and provide a reasonable fit to the experimental temperature profiles of the known clusters. Predictions emerge from the fit for the unknown matrix infrared frequencies for the C7 cluster. On the basis of the predicted concentration invariance with temperature for C7 , the infrared bands at 2128 cm-1 and 1894 cm-1 are ascribed to this linear cluster. This attribution supports the recent assignment of the gaseous 2138 cm-1 band to linear C7 .
Scaled Quantum Mechanical (SQM) Force Field Calculations of the Hexathiometadiphosphate Anion P2S2-
6
Authors: Ystenes Martin , Brockner Wolfgang , Menzel Frank 
Published: February 2015

Abstract
By ab initio quantum mechanical calculations on P2S2-
6 its equilibrium energy, geometry and vibrational frequencies along with their PED values have been obtained. The basis sets STO-5G, 6-31G, STO-5G* and 6-31G* were employed, and force field calculations were carried out at the STO-5G and the STO-5G* levels. The calculations show that the assignment for some bands between 180 and 260 cm -1 should be corrected. Two scaling factors were needed to fit the calculated frequencies with the observed frequencies within a deviation of less then 20 cm -1 for all vibrations, with the exception of v6(B1g). The calculated frequency of this vibration is very dependent on the polarization functions, and use of STO-2G for the 3d-orbitals corrects most of the deviation. STO-5G* and 6-31G* both give a good description of the geometry of the title ion, although STO-5G* yields a 0.04 Å too short terminal P - S distance.
Notizen: Comment on the Osipov-Terentjev Calculation of the Viscosity of Liquid Crystals
Authors: Stepanov V. I. 
Published: February 2015

Abstract
The calculation of the viscosity of liquid crystals based on the rotational diffusion approximation recently reported by Osipov and Terentjev [1 a] is critically examined. It is shown that the main result of their treatment - the evaluation of the activational exponent - arises from the neglect of the second derivative of the distribution function with respect to the azimuthal angle in the Fokker-Planck equation. The correct asymptotic formula for the rotational viscosity coefficient is derived.
Surface Tension Around Eutectic Compositions of Molten Alkali Carbonate Mixtures
Authors: Igarashi Kazuo , Tajiri Koji , Asashina Tadashi , Kosaka Mineo , Iwadate Yasuhiko , Mochinaga Junichi 
Published: February 2015

Abstract
The surface tension around the eutectic composition of molten binary and ternary mixtures composed of Li2CO3 with Na2CO3 and/or K2 CO3 has been measured by the maximum bubble pressure method. The surface tensions of all the three systems were represented as functions of temperature
ESR Spectra of Para-Substituted Alkyl- and Alkenylbenzene Radical Cations in Halocarbon Matrices
Authors: Kubozono Yoshihiro , Ata Masafumi , Suzuki Yasunobu , Gondo Yasuhiko , Shiotani Masaru 
Published: February 2015

Abstract
The ESR spectra of several para-substituted alkyl- and alkenylbenzene radical cations generated by 60Co γ-ray irradiation in halocarbon matrices at 77 K have been studied with the aid of semiempirical MO calculations. It has been found that the ethyl conformation of 1,4-diethylbenzene radical cation (1,4-DEB+. ) in CCl2FCClF2 is largely different from that in CCl3CF3. Further the ethyl and n-propyl groups in 4-ethyltoluene and 4-n-propyltoluene radical cations in CCl2FCClF2 take different conformations from that of 1,4-DEB +.. The conformations of the alkylbenzene radical cations depend strongly both on the matrices and on the substituent groups. A peculiar radiolytical reaction of 1,4-diisopropylbenzene to a deprotonation-type neutral radical in CCl2FCClF2 has been found, similarly to the case of photolysis.
The PN Method in the Kinetic Theory of Gases
Authors: Kügerl Georg , Schürrer Ferdinand 
Published: February 2015

Abstract
An expansion of the velocity distribution function in a series of spherical harmonics is used to transform the nonlinear Boltzmann equation into a system of moment equations. The close connection between the moment equations of zeroth and first order with the transport equations for mass, momentum and energy is pointed out. By comparing the order of magnitude of the various moments it is shown that the P2 approximation is adequate for systems with small mean free path. Simplifications of the collision terms of the moment equations are discussed, where attention is payed to the conservation laws and the H theorem
Radiolysis of Aqueous Ethanol in the Presence of CO
Authors: Park Hyoung-Ryun , Getoff Nikola 
Published: February 2015

Abstract
First, the following rate constants (in dm3 mol-1 s-1 ) were reported: k(eaq
-+ C2H5OH) = (1.2 ± 0.3) x 103, k(H + C2H5OH) = (2.8 ± 0.2) x 107 and k(OH + C 2H5OH) = (1.85 + 0.1) x 109 The major radiolytic products resulting from aqueous 10-2, 1 and 10 mol dm-3 ethanol were studied in the absence and presence of CO as a function of dose at pH 2 and 7. Probable reaction mechanisms are presented
Intramolecular and Liquid Structures of Tetramethylurea Studied by Means of X-Ray Diffraction
Authors: Radnai T. , Ohtaki H. 
Published: February 2015

Abstract
The intramolecular and liquid structures of tetramethylurea (TMU) were investigated by the liquid x-ray diffraction method. It is confirmed that in the liquid state the four methyl groups are out of the plane which is constructed by the O, C, and the two N atoms, the molecular structure being similar to what had been found in the gas phase. All structural parameters are in good agreement with those of TMU determined in the gas phase and with those of amide derivatives in the liquid phase. The liquid is characterized by a random distribution of molecules as predominant, but a weak molecular ordering characterized by approximately two intermolecular nonbonding Me ··· O distances at 340 pm is proposed
Oxygen Diffusion in YBa2Cu3O7–δ Studied via 133Ba(EC)133Cs Nuclear Quadrupole Interaction
Authors: Tröger W. , Butz T. 
Published: February 2015

Abstract
The oxygen diffusion in YBa2Cu3O7-δ was studied between 300 K and 1273 K in flowing oxygen by monitoring the 133Ba(EC)133 Cs nuclear quadrupole interaction by time differential perturbed angular correlation. The data are analyzed in a model of two different nearest neighbour oxygen configurations and yield hopping rates, the energy barrier and the difference in free enthalpy between both states. In addition, we studied the reduced system YBa2Cu3O6 +ε.
Nucleus-Carrier Interactions in the Group V Semimetals: Dependence on Temperature and Pressure
Authors: Keartland J. M. , Goudemond I. P. , Fölscher G. C. K. , Hoch M. J. R. 
Published: February 2015

Abstract
A review is given of pulsed NQR spin-lattice relaxation measurements on the rhombohedral semimetals, arsenic (As) and antimony (Sb). The nuclear spin-lattice relaxation time T1 has been measured in the temperature range 100 mK-600 K. The data follow the Korringa relation at low temperatures, but deviations from this relation are found as the temperature is increased. The results are quantitatively explained by considering interactions of the nuclei with the carriers at the Fermi surface. Above the Debye temperature (θD) the data may be understood by including a two phonon process in the analysis. The relaxation data for As and Sb are found to scale with θD. T1 has been measured for As at 295 K in the pressure range 0 - 10 kbar. The results are discussed in terms of changes in the Fermi surface parameters.