bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Theory of Relaxation in the Glass Transition Region
Authors: Baur H. 
Published: February 2015

Abstract
To begin with, relaxation equations will be generally examined within the framework of the thermo-dynamics of irreversible processes. The relaxation in the glass transition region specifically proves to be a non-linear process which resembles an accelerated or retarded autocatalytic reaction. Therefore it is physically not very useful to split the relaxation in the glass transition region into a sum of linear re-laxation mechanisms. The linear response theory and the concept of normal modes lose their validity.
Magnetic Circular Dichroism (MCD) of Four-membered Rings with four π-Electrons
Authors: Fleischhauer J. , Laura P. , Paetzold P. , Gabriel S. 
Published: February 2015

Abstract
On the basis of the perimeter model for 4N-electron [n]annulenes, algebraic expressions for the B values of perturbed four-membered rings (n = 4) with four ;r electrons (N = 1) have been derived. The results are used to interpret the MCD spectrum of l,3-di-fm-butyl-2,4-diethyI-1,3,2,4-diazadiboretidine.
Microstructure and Electrochemical Behaviour of some SnO2-based Inert Electrodes in Aluminium Electrolysis
Authors: Popescu Ana-Maria , Mihaiu Suzana , Zuca Stefania 
Published: February 2015

Some types of anodes thai could replace die usual carbon anodes in aluminium production by die Hall-Keroult process are based on SnO2. The presenr Investigation deals nidi SnO2-Sb2O3-CuO ceramics having an SnO2. conrent of ≥ 96%), Sb2O3, and CuO being dopants The ceramic pellets, thermally treated at 1400 °C for 4 hours, were analysed by X-ray diffraction and IR. spectroscopy. The structural analysis of the samples evidenced an SnO2(88) type solid solution. All samples were electronically conductive (small negative values of the Seebeck coefficients), having an sanation energy ranging within 0.02 - 0.3 eV.
The anodic polarisation curves obtained with those anodes in an electrolyte of 88 % Na3AlF6, 7% Al2O3, and 5% CaF2 were studied- The results were correlated with the microstrucrure of die invesagated samples.
Infrared and NMR Spectra of Arylsulphonamides, 4-X-C6H4SO2NH2 and i-X, j-YC6H3SO2NH2 (X=H; CH3; C2H5; F; Cl; Br; I or NO2 and i-X, j-Y=2,3-(CH3)2; 2,4-(CH3)2; 2,5- (CH3)2; 2-CH3, 4-Cl; 2-CH3, 5-Cl; 3-CH3, 4-Cl; 2,4-Cl2 or 3,4-Cl2)
Authors: Gowda B. Thimme , Jyothi K. , D’Souza J. D. 
Published: February 2015

Several arylsulphonamides of the configuration, 4-X-C6H4SO2NH2 (where X= H; CH3; C2H5;
F; Cl; Br; I or NO2) and i-X, j-YC6H3SO2NH2 (where i-X, j-Y=2,3-(CH3)2; 2,4-(CH3)2; 2,5-(CH3)2;
2-CH3,4-Cl; 2-CH3,5-Cl; 3-CH3,4-Cl; 2,4-Cl2 or 3,4-Cl2) were prepared, and their infrared spectra were measured in the solid state. The NMR spectra were recorded in solution. N-H asymmetric and symmetric stretching vibrations absorb in the ranges, 3390 - 3323 cm-1 and 3279 - 3229 cm-1,
respectively. Asymmetric and symmetric SO2 stretching vibrations appear as strong absorption lines in the ranges, 1344 - 1317 cm-1 and 1187 - 1147 cm-1, respectively. Sulphonamides exhibit S-N stretching vibrational absorptions in the range, 924 - 906 cm-1. The effect of substitution in
the phenyl ring in terms of electron withdrawing and electron donating groups could not be generalised, as the effect is non-systematic. The chemical shift is highly dependent on the electron density around the nucleus or associated with the atom to which it is bonded. Hence empirical
correlations relating the chemical shifts to the structures have been discussed. The chemical shifts of aromatic protons and carbons in all the arylsulphonamides have been calculated by adding substituent contributions to the shift of benzene, the principle of substituent addition. Considering the approximation made, the agreement between the calculated and experimental chemical shift values is reasonably good. Generally, electron-withdrawing groups shows high chemical
shifts compared to electron-donating groups.
Nematic Behaviour of a Compound EBBA – A Compuational Analysis
Authors: Pisipati V. G. K. M. , Ojha Durga Prasad 
Published: February 2015

EBBA
A computational analysis has been carried out to determine the configurational preferences of a pair of p-ethoxybenzylidine-p-n-butylaniline () molecules with respect to translatory and orientational motions. The CNDO/2 method has been employed to evaluate the net atomic charge and atomic dipole components at each atomic centre of the molecule. The configurational energy has been computed using the Rayleigh-Schrödinger perturbation method. The interaction energies obtained through these computations were used to calculate the probability of each configuration at 300 K. The energy of a molecular pair during stacking, in-plane, and terminal interaction has been calculated. The results are discussed in the light of other experimental and theoretical results.
Odd-even Effect in a Homologous Series of 4-n-Alkylbenzoic Acids: Role of Anisotropic Pair Potential
Authors: Ojha Durga Prasad , Kumar Devesh , Pisipati V. G. K. M. 
Published: February 2015

CNDO/2
A computational analysis based on quantum mechanics has been carried out to determine the association energy of seven homologues of the 4-n-alkylbenzoic acid series (n = 3, 4, 5, 6, 7, 8, and 9), using the Rayleigh-Schrödinger perturbation method for various nearest neighbour configurations of interacting pairs. The net atomic charges and dipoles have been computed using the method. An attempt is made to explain the odd-even effects at the molecular level on the basis of these results.
Conformational Structure of Chloromethyldichlorophosphines
Authors: Romanenko Evgenii A. , Nesterenko Alexander M. 
Published: February 2015

I
The 35Cl nuclear quadrupole resonances (77 K) and ab initio calculations of trichloromethyldichlorophosphine () show that it exists in the chess conformation form. The barrier to internal rotation about the P-C bond in I at the RHF/6-31++ G(d,p) level equals to 38.1 kJ mol-1. In chloromethyldichlorophosphine (II) the extension of the basis set up to the RHF/6-311++G(df, pd) level does not improve the description of the most preferable gauche-conformation; only if electron correlation (at the MP2 level) is taken into account the results are in a good agreement with experimental data.
51V NMR Study of a C15 Laves Phase Compound HfV2
Authors: Kishimoto Yutaka , Ohno Takashi 
Published: February 2015

We analyzed the K-x plot in order to investigate the change in the electronic state in the C15 Laves phase compound HfV2 at the lattice transformation temperature TL (~120 K). We could obtain K3d orb X3d orb, and X5d orb + (2/3) XPauli + Xdia, which are consistent with those reported in our previous paper, and discussed the changes in density of states of the V3d and 4s electrons at TL.
For the superconducting state we discussed the d wave Anderson-Brinkman-Morel (ABM) type energy gap in which the gap is anisotropic and vanishes at points on the Fermi surface
Theory of 14N and 17O Nuclear Quadrupole Interactions in Polyglycine and Glycine in the Protein Chain of Cytochrome c
Authors: Scheicher R. H. , Cammarere D. , Sahooa N. , Nagamine K. , Das T. P. 
Published: February 2015

As part of our ongoing investigations on hyperfine properties of nuclei and attached probes (like muon and muonium) in the protein chain of Cytochrome c (Cyt c), we have been studying the 14N and 17O nuclear quadrupole interactions in the amino acids in the protein chain at different sites where they occur. As a specific example of one of the amino acids in this context, we shall present our results on Glycine in the homo-molecular polymer Polyglycine and expectations for the hetero-molecular environment occurring at a particular region of the protein chain of Cyt c which is far enough away from the heme unit to make the results more characteristic of the chain.
In the Polyglycine polymer, our results for the 14N and 17O coupling constants e2qQ and asymmetry parameters for a central Glycine in a chain of odd numbered molecules are used to study how the e2qQ and vary with the chain length and to compare with the results for the isolated Glycine molecule. The aim is to study the convergence of the results with respect to chain length to find out the appropriate length at which the results become characteristic of the polymer chain. This conclusion is expected to provide insights into the chain length to be used in the protein to simulate the results for the protein chain in Cyt c. The Hartree-Fock Cluster procedure is being used for the investigations for all the results to be reported
Quadrupole Interactions of the Short-lived -Emitter 16N in TiO2
Authors: Minamisono T. , Matsuta K. , Miyake T. , Minamisono K. , Mihara M. , Fukuda M. , Sato K. , Zhu S.Y. 
Published: February 2015

Quadrupole interactions of 12,14N in BN(hexagonal) crystal were studied by detecting β-NQR of 12N and FT-NMR of 14N, respectively. β-NMR of 16N(Iπ= 2-, T1/2 = 7.13 s) in MgO crystal was detected to determine the magnetic moment to be |μ(16N: 2 )| = (1.986±0.001) μN. Also, the β-NQR’s of 12,16N in TiO2 crystal were detected to be |Q(16N: 2-)| = (17.9± 1.7) mb. An abnormally small effective charge for neutrons is required to account for
|Q(16N: 2-)|.
Intermolecular Interactions of Xe Atoms Confined in One-dimensional Nanochannels of Tris(o-phenylenedioxy)cyclotriphosphazene as Studied by High-pressure 129Xe NMR
Authors: Kobayashi Hirokazu , Ueda Takahiro , Miyakubo Keisuke , Eguchi Taro 
Published: February 2015

The pressure dependence of the 129Xe chemical shift tensor confined in the Tris(o-phenylenedioxy) cyclotriphosphazene (TPP) nanochannel was investigated by high-pressure 129Xe NMR spectroscopy. The observed 129Xe spectrum in the one-dimensional TPP nanochannel (0.45 nm in diameter) exhibits a powder pattern broadened by an axially symmetric chemical shift tensor. As the pressure increases from 0.02 to 7.0 MPa, a deshielding of 90 ppm is observed for the perpendicular
component of the chemical shift tensor δ⊥, whereas a deshielding of about 30 ppm is observed for the parallel one, δ‖. This suggests that the components of the chemical shift tensor, δ‖ and δ⊥, are mainly dominated by the Xe-wall and Xe-Xe interaction, respectively. Furthermore, the effect of helium, which is present along with xenon gas, on the 129Xe chemical shift is examined in detail. The average distance between the Xe atoms in the nanochannel is estimated to be 0.54 nm. This was found by using δ⊥ at the saturated pressure of xenon, and comparing the increment of the chemical
shift value in δ⊥ to that of a β -phenol/Xe compound.
Theoretical Investigations of the Spin Hamiltonian Parameters and the Local Structure of a Trigonal Co2+ Center in Bi4Ge3O12
Authors: Wu Shao-Yi , Dongb Hui-Ning 
Published: February 2015

The spin Hamiltonian parameters anisotropic g factors g||, g⊥ and hyperfine structure constants A||
and A⊥, as well as the local structure of the trigonal Co2+ center in Bi4Ge3O12 (BGO) are theoretically
investigated by the perturbation formulas of the spin Hamiltonian parameters for a 3d7 ion in
trigonal symmetry, based on the cluster approach. It is found that the impurity Co2+ substituting the
host Bi3+ undergoes an off-center displacement ΔZ(≈ −0.132 Å ) away from the center of the oxygen
octahedron along the C3 axis. The spin Hamiltonian parameters based on the above displacement
show reasonable agreement with the observed values. The results are discussed.
Theoretical Studies On The Gyromagnetic Factors For Nd3+ In Scheelites-Type ABO4 Compounds
Authors: Wu Shao-Yi , Dong Hui-Ning 
Published: February 2015

The gyromagnetic factors for Nd3+ in scheelite-type ABO4 compounds (A = Cd, Ca, Pb, Ba;
B = Mo, W) are theoretically studied by the perturbation formulas of the anisotropic g factors g∥ and g⊥ for a 4f3 ion in tetragonal symmetry. In these formulas, the contributions to the g factors
due to the second-order perturbation terms and the admixtures of various energy levels are taken
into account. The relevant crystal-field parameters are determined by the superposition model and
the local geometrical relationship of the A2+ sites occupied by the impurity Nd3+. The obtained g
factors agree reasonably with the observed values. The discrepancies between theory and experiment
are discussed.
The Millimeterwave Spectrum of Four Rare Ketene Isotopomers
Authors: Guarnieri Antonio 
Published: February 2015

The pure rotational spectra in the ground vibrational state of (1,2-13C)ketene, H2
13C=13CO, (D2,1-13C)ketene, D2C=13CO, (D2,2-13C)ketene, D2
13C=CO, and (D2,18O)ketene, D2C=C18O, have been observed in the frequency region 200 - 350 GHz. All the spectral lines have been measured in natural abundances with a source modulated millimeterwave spectrometer.
From the measured R-branch transitions a set of rotational and centrifugal distortion constants for each isotopomer could be derived, using the Watson S-reduction formalism. Further, the rotational spectra of the two isotopomers (4,5-D)ketene, D2CCO, and (4-D)ketene, DHCCO, which were already measured several years ago, have been extended to higher J-values and higher frequencies, as it is the case for all investigated isotopomers of this work. As a result of these studies a calculation of a mass-dependent structure will be the topic of a next paper.
Theoretical Explanation of the EPR Parameters of Tetragonal Ti3+ Centers in ZnSe and CdS0.75Se0.25 Semiconductors
Authors: Wu Xiao-Xuan , Feng Wen-Ling , Zhou Qing , Zheng Wen-Chen 
Published: February 2015

The electron paramagnetic resonance (EPR) parameters (g factors g||, g⊥ and hyperfine structure
constants A||, A⊥) of the tetragonal Ti3+ centers in ZnSe and CdS0.75Se0.25 semiconductors are calculated from high-order perturbation formulas based on the cluster approach. In these formulas, both
the contribution from the spin-orbit coupling parameters of the central 3dn ion and that of ligands are
considered. The calculated results show reasonable agreement with the observed values. The defect
structures of the tetragonal Ti3+ centers in both semiconductors caused by the static Jahn-Teller effect
are suggested
Structural Studies on N-(2,4,6-Trimethylphenyl)-methyl/ chloro-acetamides, 2,4,6-(CH3)3C6H2NH-CO-CH3–yXy (X = CH3 or Cl and y = 0, 1, 2)
Authors: Gowda Basavalinganadoddy Thimme , Kožíšek Jozef , Fuess Hartmut 
Published: February 2015

TMPA
The effect of substitutions in the ring and in the side chain on the crystal structure of N- (2,4,6-trimethylphenyl)-methyl/chloro-acetamides of the configuration 2,4,6-(CH3)3C6H2NH-COCH3− yXy (X = CH3 or Cl and y = 0,1, 2) has been studied by determining the crystal structures of N-(2,4,6-trimethylphenyl)-acetamide, 2,4,6-(CH3)3C6H2NH-CO-CH3 (); N-(2,4,6- trimethylphenyl)-2-methylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2-CH3 (TMPMA); N-(2,4,6- trimethylphenyl)-2,2-dimethylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH(CH3)2 (TMPDMA) and N-(2,4,6-trimethylphenyl)-2,2-dichloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CHCl2 (TMPDCA). The crystallographic system, space group, formula units and lattice constants in Å are: TMPA: monoclinic, Pn, Z = 2, a = 8.142(3), b = 8.469(3), c = 8.223(3), β = 113.61(2)◦; TMPMA: monoclinic, P21/n, Z = 8, a = 9.103(1), b = 15.812(2), c = 16.4787(19), α = 89.974(10)◦, β = 96.951(10)◦, γ =89.967(10)◦; TMPDMA: monoclinic, P21/c, Z = 4, a =4.757(1), b= 24.644(4), c =10.785(2), β = 99.647(17)◦; TMPDCA: triclinic, P¯1, Z = 2, a = 4.652(1), b = 11.006(1), c = 12.369(1), α = 82.521(7)◦, β = 83.09(1)◦, γ = 79.84(1)◦. The results are analyzed along with the structural data of N-phenylacetamide, C6H5NH-CO-CH3; N-(2,4,6-trimethylphenyl)-2-chloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)-acetamide, 2,4,6-Cl3C6H2NH-COCH3; N-(2,4,6-trichlorophenyl)-2-chloroacetamide, 2,4,6-Cl3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)- 2,2-dichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CHCl2 and N-(2,4,6-trichlorophenyl)- 2,2,2-trichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CCl3. TMPA, TMPMA and TMPDCA have one molecule each in their asymmetric units, while TMPDMA has two molecules in its asymmetric unit. Changes in the mean ring distances are smaller on substitution as the effect has to be transmitted through the peptide linkage. The comparison of the other bond parameters reveal that there are significant changes in them on substitution.
Effect of Substitution on the Molecular Geometry of N-(2/3/4-Substituted-phenyl)-2,2-dichloro-acetamides, 2/3/4-XC6H4NH-CO-CHCl2 (X = CH3 or Cl)
Authors: Gowda Basavalinganadoddy Thimme , Paulus Helmut , Kožíšek Jozef 
Published: February 2015

2MPDCA
The effect of ring substitution on the molecular geometry of amides of the type 2/3/4-XC6H4NHCO- CHCl2 (X = CH3 or Cl) has been studied by determining the crystal structures of the compounds N-(2-methylphenyl)-2,2-dichloro-acetamide, 2-CH3C6H4NH-CO-CHCl2 (); N-(3-methylphenyl)- 2,2-dichloro-acetamide, 3-CH3C6H4NH-CO-CHCl2 (3MPDCA) and N-(3-chlorophenyl)- 2,2-dichloro-acetamide, 3-ClC6H4NH-CO-CHCl2 (3CPDCA). The results are analyzed along with our earlier crystal structures of the amides N-(phenyl)-2,2-dichloro-acetamide, C6H5NH-COCHCl2 (PDCA); N-chloro-N-(phenyl)-2,2-dichloro-acetamide, C6H5NCl-CO-CHCl2 (NCPDCA); N-(4-methylphenyl)-2,2-dichloro-acetamide, 4-CH3C6H4NH-CO-CHCl2 (4MPDCA); N-(2-chlorophenyl)- 2,2-dichloro-acetamide, 2-ClC6H4NH-CO-CHCl2 (2CPDCA); N-(4-chlorophenyl)-2,2-dichloro- acetamide, 4-ClC6H4NH-CO-CHCl2 (4CPDCA). The results have also been compared and correlated with the crystal structure data of trichloro-acetamide analogues of the type 2/3/4- XC6H4NH-CO-CCl3 (X = CH3 or Cl): N-(phenyl)-2,2,2-trichloro-acetamide, N-(2-methylphenyl)- 2,2,2-trichloro-acetamide, N-(3-methylphenyl)-2,2,2-trichloro-acetamide, N-(4-methylphenyl)- 2,2,2-trichloro-acetamide, N-(2-chlorophenyl)-2,2,2-trichloro-acetamide, N-(3-chlorophenyl)-2,2,2- trichloro-acetamide, N-(4-chlorophenyl)-2,2,2-trichloro-acetamide, N-chloro-N-(phenyl)-2,2,2-trichloro- acetamide and N-(phenyl)-acetamide. The crystal system, space group, formula units and lattice constants in Å of the new structures are: 2MPDCA: monoclinic, P21/n, Z = 4, a = 4.7059(5), b = 11.600(1), c = 18.918(2), β = 94.702(9)° ; 3MPDCA: orthorhombic, P212121, Z = 4, a = 4.759(1), b = 10.543(3), c = 20.205(5); 3CPDCA: orthorhombic, Pnma, Z = 4, a = 9.935(1), b = 6.997(1), c = 14.140(2). 2MPDCA, 3MPDCA and 3CPDCA show a molecule each in their asymmetric units, in agreement with the observed 35Cl NQR spectra of the compounds
Investigation of the Local Geometry and EPR Parameters of V3+ and Cr4+ Centers in Al2O3 Crystals
Authors: Feng Wen-Lin , Wu Xiao-Xuan , Wang Fang , Zheng Wen-Chen 
Published: February 2015

The EPR parameters (zero-field splitting D and g factors g||, g⊥) of 3d2 V3+ and Cr4+ centers in Al2O3 crystals are calculated by using the diagonalization of the complete energy matrix for 3d2 ions in trigonal symmetry. The crystalfield parameters are estimated for the superposition model related to the local geometry (or structure) of the impurity centers. From the calculations, the EPR parameters for both impurity centers are explained and the local structures (characterized
by the impurity displacement Δz along the C3 axis and the displacement Δx of O2− ions in the oxygen triangle between the impurity and the vacant oxygen octahedron along the x-axis, resulting from the electrostatic repulsive force and the electronic cloud overlap) of these impurity centers are estimated. The results are discussed.
Effects of The Vibrational and Rotational Energy on Reaction Cross- Section in a Classical Trajectory Study of Atom-Diatomic Molecule Collisions
Authors: Abdel-Halim Hamzeh M. , Jaafreh Sawsan M. 
Published: February 2015

Effects of the initial vibrational and rotational energy of a diatomic molecule on reaction rates of atom-diatomic molecule reactions have been studied using classical trajectory calculations. The reaction probabilities, cross-sections and rate constants were calculated using the three-dimensional Monte-Carlo method. Equations of motion, which predict the positions and momenta of the colliding particles after each step in the trajectory, have been integrated numerically by the Runge-Kutta-Gill and Adams-Moulton methods. Morse potential energy surfaces were used to describe the interaction between the atom and each atom in the diatomic molecule. Several atom-diatomic molecule systems were studied. Variation of the reaction cross-section with both vibrational and rotational quantum numbers has been studied. For all systems studied, it was found that the cross-section increases with the vibrational quantum number. However, the effect of rotational quantum number on cross-section varies from one system to another.
Results obtained in the present work were compared with experimental data and/or with results obtained theoretically. Good agreements were observed with experimental and with theoretical results obtained by other investigators using different calculation methods.
Design and Construction of Equipment to Make Adsorption at Pilot Plant Scale of Heavy Metals
Authors: Moreno-Piraján Juan C. , Rangel David , Amaya Bibiana , Vargas Edgar M. , Giraldo Liliana 
Published: February 2015

The purpose of this paper was to illustrate the procedure to obtain activated carbon from lignocellulosic residues through chemical and physical paths. A general surface characterization was made and aqueous solution isotherms were obtained in order to evaluate the behaviour of each carbon atom in solutions contaminated with selective ions. The other purpose was to show a simple way to perform a scale-up process of an absorber from the laboratory level to an industrial level, using the breaking curves in fixed beds developed through the continuous pursuit of the Pb(II) and Cr(VI) ions concentration in the effluent of the bed. Activated carbon was used to study the adsorption of Pb(II) and Cr(VI). Isotherms of aqueous adsorption were determined. This model was developed in order to examine its efficiency and to compare it with an experimental model made in the laboratory, which rendered very similar results. The main characteristic of the feasibility of the application of this design is the fact that neither tedious calculations nor mass transfer coefficients are required in order to construct the above-mentioned curves. The model was developed by applying concepts such as mass transfer zone (MTZ) and length of unused bed (LUB), which are the dynamical basis understanding for the adsorption process in fixed beds.
As a complementary item of the experiment, within a pilot plant scale, a filter was developed in order to achieve flexibility when manipulating the most important adsorption parameters and to enable the control of the variables involved in the process that change the operating conditions.
Application of He’s Homotopy Perturbation Method for Solving Fractional Fokker-Planck Equations
Authors: Mousa Mohamed M. , Kaltayev Aidarkhan 
Published: February 2015

Abstract
The fractional Fokker-Planck equation (FFPE) has been used in many physical transport problems which take place under the influence of an external force field and other important applications in various areas of engineering and physics. In this paper, by means of the homotopy perturbation method (HPM), exact and approximate solutions are obtained for two classes of the FFPE initial value problems. The method gives an analytic solution in the form of a convergent series with easily computed components. The obtained results show that the HPM is easy to implement, accurate and reliable for solving FFPEs. The method introduces a promising tool for solving other types of differential equation with fractional order derivatives