bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enthalpies of Mixing for the Liquid System Formic Acid + Acetic Acid
Authors: Haase R. , Jansen H.-J. , Puder K. , Winter B. 
Published: February 2015

Abstract
After a short description of the evaluation of the calorimetric measurements, we give the results for the enthalpies of mixing in the liquid system formic acid + acetic acid. The molar excess enthalpy H̄E has been determined as a function of the mole fraction x of acetic acid at 18 °C, 20 °C, 25 °C, 30 °C, and 40 °C. The function H̄E (x) is always positive and nearly symmetric (with a maximum at about x = 0.5) and increases with increasing temperature. A three-parameter fit of the function H̄E (x) has been achieved for each temperature.
Das UV/VIS-Absorptionsspektrum des 9.9′-Dianthryl-disulfids / The UV /VIS Absorption Spectrum of 9,9′-Dianthryl disulphide
Authors: Zander M. , Zellerhoff R. B. 
Published: February 2015

Abstract
9,9′-Dianthryl disulphide is the first example studied for a diaryl disulphide whose uv/vis absorption spectrum exhibits a distinct vibrational structure whereas the formerly investigated spectra of diphenyl disulphide and the isomeric dinaphthyl disulphides are characterized by the complete lack of vibrational structure. Different interpretations have been given in the literature for this particular property of the diphenyl disulphide and dinaphthyl disulphide spectra. The long wave-length region of the dianthryl disulphide spectrum is interpreted with the assumption of three electronic transitions. Two of them are localized in the anthracene or dithio anthracene chromophore, respectively, whereas the third transition is assumed to be non-localized including the whole system with the S-S bridge acting as a conjugative (butadienoid) link. This assignment is consistent with a pπ-model without pπ/dπ-participation in agreement with results of photoelectron spectral investigations on disulphides reported in the literature.
On the Applicability of Redington's Method of Determination of Force Field to Bent XYZ Type Systems
Authors: Namasivayam R. , Mayilavelan S. 
Published: February 2015

Abstract
Force fields of NSF, NSCl, NSBr, SSO, HCO, HOF, HOCl, HOBr and HOI have been computed using Redington’s method. The angle parameters φ12, φ13 and φ23 are fixed through Fsteep critical point solution. The parametrised eigenvector matrices obtained are found to possess the properties predicted by Peacock et al. Mean amplitudes of vibration, Coriolis coupling constants, inertia defects and centrifugal distortion constants have also been calculated and compared with literature values. Redington’s approach is found to reproduce all the molecular constants with accuracies comparable with conventional methods.
An Analysis of Lattice Dynamical Angular Force Models for Body Centered Cubic Metals
Authors: Khanna R. N. , Rathore R. P. S. 
Published: February 2015

Abstract
Present angular force models for lattice dynamical behaviour of body centered cubic (bcc) metals have been analysed for the satisfaction of rotational invariance and general equilibrium conditions. It has been found that most of the angular force models (except that due to Clark et al.) are deficient and leave the lattice under stress. Further it has been inferred that either the axially symmetric or the central pair potential schemes, incorporating the concept of electron pressure, provide the realistic picture of lattice excitations in metals.
Elektronisches Resonanz-Raman-Spektrum von ((C2H5)4N)2[ReI6]/ Electronic Resonance-Raman Spectrum of ((C2H5)4N)2[ReI6]
Authors: Homborg H. 
Published: February 2015

Abstract
The electronic Raman spectrum of hexaiodorhenate (IV) has been measured at 80 K. Under resonance-Raman conditions an enhancement of the Raman intensity occured for the totally symmetric a1g -vibrational mode coupled to the electronic transition Γ8(4A2g) → Γ8(2T1g) .
Raman-Spektroskopische Untersuchungen an PCl5. IV. Das System PCl5 —SnCl4 / Raman Spectra of the System PCl5 -SnCl4
Authors: Brockner W. , Demiray A. F. 
Published: February 2015

Abstract
Raman spectra of some solid and molten PCl5- -SnCl4- mixtures have been recorded. According to the stoichiometry SnCl5
- and additional SnCl6
2- complex ions are present in the solid state. The 1 : 1 melt is built up by PCl4
+ and SnCl5
- ions. PCl5 rich melts contain PCl5 molecules in addition, but almost no SnCl6
2-. SnCl4 rich melt mixtures are composed of PCl4
+ , SnCl5
- and SnCl4 .
Interaction of the Quinoline Derivatives with Coenzyme Q10
Authors: Al-Khuzzaii Suhaila , Al-Rufaie Elham M. , Khalil Salim M. , Shanshal Muthana 
Published: February 2015

Abstract
The interaction of the quinoline derivatives with CoQ10 is studied both experimentally, using Polarographie and spectrophotometric techniques, and theoretically, applying the perturbation molecular orbital theory. The E1/2 potentials of a series of 1:1 solution mixtures of quinoline derivatives with CoQ10 are measured and compared with E1/2 of the coenzyme alone (0.52 V). An increase in the E1/2-magnitude of the coenzyme is detected (⊿E1/2 ≈ 0.03-0.13 V). Simple perturbation molecular orbital treatment shows an increase in the energy of the lowest unoccuppied molecular orbital of the coenzyme due to the same interaction, in agreement with the Polarographie results. The complexation constants of the same quinoline derivatives, as well as the antimalarials quinine, primaquine and chloroquine, with CoQ10 are determined spectrophotometrically and found to be in the order of 105 . The K value for each complex is determined at 10 different wavelengths and 7 different constituent concentrations of the solution. The complexation enthalpies are all small and positive (0.98-4.53 kcal/mol), the entropies are big and positive (29-41 cal/deg.mol). The big entropy change suggests an increase in the internal motion of the complexing molecules. It is suggested that the increase in the internal motion is due to the increase in the motion of the isoprenoid side chain of the coenzyme.
An Investigation of the Positive Column of a Hollow Cathode Arc in a Magnetic Field. Part I
Authors: Boeschoten F. , Komen R. , Sens A. F. C. 
Published: February 2015

The positive column of the hollow cathode arc consists of a highly ionized ( > 90%) and -magnetized (ωei τi,i > 1) plasma. In order to obtain as much as possible information about this plasma its parameters were measured as functions of radius, r, and axial distance, z. They were varied by changing the discharge parameters - arc current I , gas feed Q, magnetic field strength B, arc length L and core diameter d. Generally the discharge was fed with Argon, but Neon, Helium, Nitrogen and Hydrogen were also used.
- The radial plasma density distribution, ne(r), is approximately Gaussian for 0 ≦ r < 4 cm (ne(0)≅ 2 X 1014 part./cm3); in axial direction the plasma density does not vary much.
-The ion temperature, Ti, is constant with radius, contrary to the electron temperature, Te, which drops sharply near the core of the arc. In axial direction Ti drops by a factor ten from the cathode to the anode (Ti ≅ 1- 30 eV). Ti (z = 0) increases with arc length L.
- The whole plasma moves in axial direction from the cathode towards the anode ( υz ≅ 6 X 104 cm/s); the angular mass velocity (Ω ≅ some 105 rad/s) is strongly sheared and decreases with temperature.
- The axial electrical field is small (0.1 to 0.2 V/cm) corresponding to a normal electrical conductivity. The radial electrical field points inwardly and varies strongly with radius (0 ≧ Er ≳ - 10 V/cm).
- Strong (nonlinear) low frequency oscillations (υ ≅ 15 kHz) are generated spontaneously in the plasma; these oscillations are due to the Kelvin-Helmholtz instability.
As is shown in Part II of this investigation, the observed behaviour of the plasma column may be satisfactorily explained by the two fluid model with MHD ordering. Due to viscous effects (i, i collisions) the sheared plasma rotation has big consequences for the transport of particles and energy.
Nuclear Magnetic Resonance in Solid Zinc
Authors: Herberg H. , Abart J. , Voitländer J. 
Published: February 2015

Abstract
The nuclear magnetic resonance of 67Zn in hexagonal close-packed Zn metal has been observed at 4.2 K by pulsed NMR with three different frequencies. The spin echo profile showed a well resolved powder pattern due to electric quadrupole interaction. The quadrupole coupling constant was determined to be e2 q Q/h = 12.0 (4) MHz. The spin-spin and spin-lattice-relaxation times were measured to be T2 = 58 ± 2 ms and T1 = 0.45 ± 0.2 s, respectively. The isotropic Knight shift is found to have the value Kiso = 0.1 ± 0.05%.
Evidence for Polymorphism within the So-called "Blue Phase" of Cholesteric Esters. IV. Temperature and Angular Dependence of Selective Reflection
Authors: Bergmann K. , Stegemeyer H. 
Published: February 2015

Abstract
From selective reflection (SR) measurements as a function of temperature it has been shown that cholesteryl myristate exhibits two "blue phases" (BP) between the isotropic and the cholesteric state. The SR of the two BP shows the same angular dependence as found in the cor-responding cholesteric state. From our results a model of the BP is proposed with the molecular axes inclined to the helix axis by a critical angle of 54.74° explaining the absence of birefringence as well as the cholesteric-like optical properties.
Dipole Moments, Polarizabilities and the Fluorescence Behaviour of 4-(9-anthryl)-N,N-dimethylaniline
Authors: Baumann Wolfram , Petzke F. , Loosen K.-D. 
Published: February 2015

Abstract
It is shown that the solvent dependence of the fluorescence wavenumber and decay time as well as the solvent dependent effect of an external electric field on the absorption and fluorescence spectra of 4-(9-anthryl)-N,N-dimethylaniline can be fully understood taking into account reaction field induced polarizability effects.
Infrared Spectra of Matrix Isolated Alkali Tetrafluoroaluminates, AlkAlF4 (g)
Authors: Huglen Reidar , Cyvin Sven J. , Øye Harald A. 
Published: February 2015

Abstract
The 1 : 1 adduct compounds which are the prevailing vapour species over equimolar mixtures of AlkF and AlF3 (Alk = Li, Na, K, Rb and Cs) in the temperature range 450-750°C have been isolated in argon and nitrogen matrices and examined bv infrared spectroscopy. Seven frequencies which are assigned to matrix isolated alkali tetrafluoroaluminate molecules have been found for all systems investigated. Group theoretical analysis and subsequent normal coordinate computations of the reassigned frequencies confirm a structural model for the AlkAlF4 molecules having the symmetry C2v-However, the results from this analysis cannot be taken as a definite confirmation of a true bidentate structure for these molecules in the vapour phase. The alkali metal-fluorine bond is found to be rather weak, and the Al-F terminal bond is found to be stronger than the Al-F bridge bond. Qualitative relations between matrix as well as vibrational shifts and potential energy distribution are discussed.
The Molecular Structure of 2-Methyloxacyclobutane, as Studied by Electron Diffraction
Authors: Schultz György , Bartók Mihály 
Published: February 2015

Abstract
A gas electron diffraction study of 2-methyloxacyclobutane has been carried out at room nozzle temperature. The four membered ring takes a planar conformation. The mean ra values for the O-C, C-C and C-H bonds are 1.448(5)A, 1.534(4)A and 1.118(3) Å, respectively. The endocyclic bond angles are C-C-C = 85.5(18)° and C-C-O=91.2 (15)°, while the angle C-O-C was assumed to be 92°. The position of exocyclic carbon atom was characterized, in addition by < Cexocyclic-C-O = 110.7(7)° and torsional angle Cexocyclic-C-O-C = 59.6(40)° (0° corresponds to the anti position of Cexocyclic-C and O-C bonds).
Lattice Animals as Limits of Clusters in Percolation Theory
Authors: Rocksloh B. , Stauffer D. 
Published: February 2015

Abstract
We investigate if the limits p → 0 or p → 1 for large percolation clusters at concentration p correspond to large lattice animals for fixed size s or fixed perimeter t, respectively. A numerical analysis for the asymptotic number of lattice animals with fixed large perimeter shows that the limit s → ∞ can be interchanged with the limit p → 0, but the two limits t → ∞ and p → 1 cannot be interchanged.
ESR-Relaxation von FeCl4
- -Komplexen in elektrisch polaren organischen Lösungsmitteln
Authors: Dietz W. 
Published: February 2015

Abstract
ESR-linewidths at X-band and Q-band frequencies of FeCl4
- in dilute organic solvents (ketones, nitriles, amides and aliphatic alcohols up to n-decanol) at room-temperature are reported. Correlation times and structural parameters of zero field splitting (ZFS) modulation are discussed with respect to the effective relaxation process. It can be shown that for the non-associating solvents the modulation of the ZFS is due to collisions with molecules tumbling in the solvent sheet. In alcoholic solution the rotating hydroxyl group of not associated molecules in the neighbourhood of the chlorine ligands must be assumed to determine the dynamics of the ZFS-modulation.
Triplet State Properties of Binary Mixed Crystals of Dibenzofuran and Fluorene
Authors: Schweitzer D. , Zimmermann H. 
Published: February 2015

Abstract
Phosphorescence spectra and ODMR measurements at 1.3 K on a series of 13 mixed crystals of dibenzofuran (DBF) and fluorene (F) as well as of neat crystals of DBF and F (X-traps) are reported. Drastic changes in the spectra with different F:DBF ratios are observed, demonstrating the possibility of investigations of the electronic properties of F monomers, dimers, trimers and larger aggregates in this mixed crystal system of two chemically different molecules.
Elektrotransportversuche mit epitaktischen Goldschichten
Authors: Kleinn W. , Hübner H. 
Published: February 2015

Abstract
Electrotransport Experiments with Epitaxial Gold Films Electrotransport in gold films of 60 nm thickness grown epitaxially onto hot (100) NaCl substrate is determined from the growth rate of voids forming in the temperature gradient in short specimens observed in the transmission electron microscope while loaded with direct current densities of several 106 A/cm2 . For the temperature range 631 -1214 K an activation energy (1,19 ± 0,05) eV is found.
The Nature of Chaos in a Simple Dynamical System
Authors: Shibata Akira , Mayuyama Toshihiro , Mizutani Masahiro , Saitô Nobuhiko 
Published: February 2015

A simple one-dimensional transformation xn = axn-1 + 2 - a (0 ≦ xn-1 ≦ 1 - 1 / a ) ,
xn = a( 1 - xn-1) (1 - 1 a ≦ xn-1 ≦ 1) (1 ≦ a ≦ 2) is investigated by introducing the probability distribution function Wn(x). Wn ( x ) converges when n → oo for a > V 2 , but oscillates for 1 < a ≦ V2. The final distribution of Wn(x) does not depend on the initial distributions for a > V2, but does for 1 < a ≦V2 Time-correlation functions are also calculated
On the Electronic Structure of Metal Hydrides I. Exposition of a Many-Electron Theory
Authors: Wahl F. , Baumann G. 
Published: February 2015

Abstract
We present the concept of a many-electron theory for the calculation of the energy difference between an undisturbed metallic host lattice and a crystal disturbed by stored hydrogen atoms. With the help of an elimination procedure a multidimensional system of equations is reduced to a one-particle Schrödinger equation for the electron of the hydrogen. The interaction with the electrons of the metal is then described by a dynamical potential depending on the state of the electron itself. A first order approximation with static screening is discussed and then generalized to a self-consistent calculation of one-electron functions which are used as a basis for expansions.
Mikrowellen-Spektrum und Struktur des Methyldichlorsilans / The Microwave Spectroscopy and the structures of Methyl-di-chloro-Silane
Authors: Kraft H.-G. , Haas B. , Zeil W. 
Published: February 2015

Abstract
By microwave spectroscopy (Stark-spectroscopy and microwave/microwave double resonance spectroscopy) we determined the structure of Methyl-di-chloro-silane. A partial rs-and complete r0-structure is given. The structure is in good agreement with some relationships concerning the structure of related molecules given by other authors.
Infrarotabsorption von reinem Dichlormethan bis zu hohen Drücken und Temperaturen / Infrared Absorption of Pure Dichloromethane Measured up to High Pressures and Temperatures
Authors: Buback M. , Franck E. U. , Lendlc H. 
Published: February 2015

Abstract
The infrared absorption of the ν1 and ν6 stretching fundamentals and of the ν2 CH2-bending mode in pure dichloromethane has been measured up to pressures and temperatures of 2 kbar and 200 °C, respectively. The optical high pressure cells were equipped with CaF2 single crystal windows. The applicability of this window material at high pressures and temperatures was investigated.
With increasing density the wavenumbers of maximum absorption of ν1 and ν2 shift to lower and of ν6 to higher values. The integrated molar absorptivity of ν2 and ν6 increases with in-creasing density while it remains nearly constant for the ν1 vibration.
The results obtained for the C-H modes clearly differ from those measured for O-H or N-H vibrations in polar materials. They are attributed to the action of repulsive forces in dense CH2Cl2.
Molecular Orbital Calculations on Penta Coordinated Ferric Dithiocarbamates Exhibiting Intermediate and Low Spin Ground States
Authors: Ganguli P. , Hasselbach K. M. 
Published: February 2015

Abstract
SCCEHMO calculations show that the ground state in [Fe(dtc)2X], X = Cl, Br, I and NCS, is 4A2: (x2 - y2)2(xz)1(yz)1(z2)1(xy)0 and for X = NO is 2A1: (xz)2(yz)2(x2-y2)2(z2)1(xy)0. The calculated quadrupole splittings of iron and iodine included the valence shell, overlap charge, and the ligand and lattice contributions to the EFG tensor at the nuclei. In addition, the elec-tron densities at the iron nucleus are compared with the measured isomer shifts. The spin densi-ties may be interpreted in terms of a π-delocalization. The results are discussed on the basis of the molecular orbital energy level schemes.
Binding Energies in Zr from (d, p) and (d, t) Reactions
Authors: Borello-Lewin T. , Dietzsch O. 
Published: February 2015

Abstract
Neutron separation energies in 91Zr, 92Zr, 93Zr and 95Zr were determined by measurements of relative Q-values for (d, p) reactions on Zr isotopes. A comparison is made with separation energies derived from a previous measurement of (d, t) reaction Q-values. The neutron separation energy in 95Zr disagrees by three standard deviations with the adjusted value in the 1977 Atomic Mass Evaluation.
On the Evaluation of the Specific Mass Shift in the Ground States of Members of the He Isoelectronic Series
Authors: Saha Subal , Sengupta Sankar 
Published: February 2015

Abstract
A variation-perturbation method to calculate the specific mass shift in the ground state configuration of members of the He isoelectronic series is proposed. Through minimization of the second order energy, completely coupled and correlated orbitals are obtained in the Hartree Fock approximation. The influence of the Pauli principle and the electrostatic interaction on the motion of the electrons are automatically included while estimating the specific mass shift. This procedure also enables expectation values of the operator r1 · r2 to be calculated easily.
Silicon Compounds in the Jupiter Atmosphere
Authors: Howland Glenn , Harteck Paul , Reeves Robert R. 
Published: February 2015

Abstract
Due to the relatively large cosmic abundance of Si and the stability of colored silicon compounds easily formed under various nonequilibrium conditions, it is concluded here that silicon should be strongly considered as a potential major component in the observed colored material in the Jupiter atmosphere. Silicon is one of the most abundant elements in the universe (after H, He, 0, N, and C) and in the same order of abundance as Mg and Fe. In the high temperature and pressure regions of Jupiter most of the Si should be present as SiH4. At higher altitudes, corresponding to a total pressure of less than 1000 bar and a temperature below 1200 K, SiC>2 and other compounds of silicon should dominate. These equilibria and the chemistry depend strongly upon the H9O concentration, which is assumed to be in the order of 10~ 3 . A calculated equilibrium profile had been proposed for a model atmosphere [1] and our own estimates confirm the main features within reasonable limits. Recent photographs taken of Jupiter emphasize the fact that the atmosphere of the planet is not in equilibrium. Atmospheric turbulence is observed corresponding to movement in the colored areas including the well-known great red spot. Assuming, therefore, that non-equilibrium processes may occur on Jupiter, the nature of such processes may be sought in the laboratory. The non-equilibrium transition of SiH4 to Si(>2 can be observed in various ways. We have found that many of these lead to intermediates that are relatively stable and yield strong colorations very similar in appearance to those observed on Jupiter. The purpose of this paper is to emphasize the possibility of the silicon compounds contributing
A Double Hard Sphere Model of Liquid Semi-Metals: Applications to Bismuth and Tin
Authors: Orton B. R. 
Published: February 2015

Abstract
The double hard sphere model previously used to calculate the interference functions for liquid Ge, Sb and Ga has now been applied to Sn and Bi. The main features of the observed interference functions just above the melting points have been reproduced, within experimental error, by the superposition of two different partial interference functions represented by hard sphere functions with packing densities of 0.475 and 0.470 for Sn and 0.430 and 0.400 for Bi and respective hard sphere diameters; 3.030 Å and 2.420 Å: 3.335 Å and 2.450 Å. The model has been developed to give a qualitative picture of the bonding in the liquid with the short distance associated with possible overlap of p orbitals. Further, this model has been shown to be in keeping with an alternative employing a ledge type interatomic potential by referring to the measured compressibilities.
Noble Gases in Ten Stone Meteorites from Antarctica
Authors: Weber Hartwig W. , Schultz Ludolf 
Published: February 2015

Abstract
The concentrations and isotopic composition of noble gases have been determined in all ten stone meteorites recovered in Antarctica during 1976-1977 by a U.S.-Japanese expedition. From a comparison of spallogenic and radiogenic gas components it is concluded that the chondrites Mt. Baldr (a) and Mt. Baldr (b) belong to the same fall but that all other stone meteorites are individual finds.
Stability of Internal Modes in Circularly Cylindrical MDH Equilibria
Authors: Lortz D. , Nührenberg J. 
Published: February 2015

Abstract
The stability of internal modes, i.e. modes which leave the plasma boundary unperturbed, is discussed for magnetohydrostatic equilibria in circularly cylindrical symmetry. Stability analysis can be performed analytically by expansion near the magnetic axis. Marginal stability conditions relating the pressure gradient and the shear are determined.
Quantitative Analysis of Microsegregation in the Faceted and Non-Faceted Czochralski Silicon Crystal Growth
Authors: Kim K. M. 
Published: February 2015

Abstract
The microsegregation behaviour of antimony in the faceted and non-faceted Czochralski silicon crystal growth was analyzed quantitatively. Using small melt heights and no rotation, dopant striations of various small spacings were eliminated. Interface demarcation and spreading resistance measurements were used for the segregation analysis. The dopant concentration and its fluctuation during the faceted growth were both higher than during non-faceted growth. On the other hand, fluctuations of the microscopic growth rate were about the same in magnitude and periodicity in the two growth regions.