bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Energy Sputtering from Cleaned Metal Foils
Authors: Krueger F. R. , Wien K. 
Published: February 2015

Abstract
Positive and negative secondary ions desorbed from metal foils by bombardment with 252Cf fission products have been investigated by time-of-flight mass spectroscopy. The measurements were performed under UHV conditions using metal foils of Cu, Ni and Al cleaned by Ar-ion etching. Spectra were taken with cleaned surfaces and also under the exposure of H2 , O2 , N2 , CO, C2H4 , C2H6 and C3H7OH up to several 100 L. The yields of metal ions from clean metal surfaces are in agreement with Sigmund' theory.
Nachweis der verschiedenen Phasen und Phasenübergänge des Systems Fe-Ga im Konzentrationsbereich 25,7 bis 28,3 At-% Ga bei Temperaturen von 20 °C bis 720 °C mit Hilfe des Mössbauer- Effekts
Authors: Tiemann K. , Schmand J. 
Published: February 2015

Abstract
Fe-Ga-absorbers, bcc-unordered at 20 °C, with 25.7, 27.0, and 28.3 at-% Ga were analyzed up to 720 °C with the Mössbauer effect in order to clear disagreements of former experiments of us with the then known phase diagrams. We found proofs for an ordering transition A2 -DO3 between 180 and 260 °C, a transition DO3 -Ll2 between 280 and 380 °C, a transition Ll2 -DO19 in a small temperature interval at 610 °C, and a further one DO19 - DO3 (or DO19-B2) at 630 °C. The temperature dependence of the magnetically induced Ll2-field gradient q was analyzed. Probably q is negative, while the direction of the magnetic field is parallel [1, 0, 0] in agreement with other experiments at low temperatures. Above 630 °C there seems to exist a further so far unknown ordered phase, which is probably non-cubic with at least two different Fe-sites. Our results are in considerable agreement with recently published phase diagrams, though some of our spectra allow different interpretations.
Magnetische Suszeptibilität von destilliertem Lithium zwischen 294 und 3,7 K
Authors: Lueken Heiko 
Published: February 2015

Abstract
The magnetic susceptibility of distilled lithium has been determined over the temperature range 294 - 3.7 K. The obtained room temperature value of the mass susceptibility is (3.44±0.08)·10-6 cm3 g-1 (cgs units). Below 20 K the susceptibility of the mixture of hexagonal close-packed and body-centered cubic lithium has increased at a rate of about 16%.
The Creation of a Photon: A Heuristic Calculation of Planck’s Constant ħ or the Fine Structure Constant α
Authors: Barut A. O. 
Published: February 2015

,
A dynamical mechanism is presented to calculate Planck’s constant ħhence α. Because the charge inside the electron performs a zitterbewegung, the relativistic radiation theory is applied to this motion of the charge, rather than to its “center of mass” motion. With a small Doppler-correction the value obtained is α-1 = 137.03. Some tests of the theory are suggested.
ClNO-katalysierter ClNO2-Zerfall in 1-Chlorperfluorheptan / ClNO-catalysed decomposition of ClNO2 in 1-chloroperfluoroheptane
Authors: Knauth H.-D. , Martin H. , Schlapkohl H. 
Published: February 2015

The thermal decomposition of ClNO2 in the presence of ClNO was investigated between 353 K and 373 K in solution (C7F15Cl) by spectral photometric means. ClNO catalyses the decomposition by the steps

The Arrhenius parameters for the rate determining step of the catalysed reaction was found to be
A/cm3 mol-1 s-1 = 1012.17±0.32; E/kJ mol-1 = 79.5±2.1.
Kinetics of the Reversible Transformation of 2,3-Dioxogulonic Acid into its Enol as a Function of the pH of the Medium
Authors: Zuluaga J. , Martínez P. 
Published: February 2015

Abstract
2,3-dioxogulonic acid and the disodium salt of its enol were synthesised, isolated and identified both chemically and spectroscopically. A kinetic study was carried out on its equilibrium by means of the “stopped flow” method for rapid processes, and the rate constants for the forward and backward reaction were determined as a function of the pH of the medium. The kinetic coefficients involved, equilibrium constant and Gibbs free energies were also determined.
Optical Spectra of Chlorophyll a and b Molecules and Complexes in PMMA and MTHF
Authors: Hägele W. , Schmid D. , Drissler F. , Nauš J. , Wolf H. C. 
Published: February 2015

Abstract
The optical spectra of chlorophyll a and chlorophyll b in PMMA and MTHF were studied over a wide range of concentration (8 X 10-6-1 X 10-3 mole/l in PMMA, and 10-6-10-1 mole/l in MTHF). In the absorption spectra it is possible to identify bands which originate from chlorophyll disolvates and chlorophyll monosolvates in MTHF as well as bands which are most probably due to isolated chlorophyll molecules in PMMA. In high-concentration samples of chlorophyll in MTHF some bands may be assigned to aggregates, but based on optical results only, no particular model can be proposed. The emission spectra are strongly influenced by reabsorption and energy transfer processes. However, the so-called Qy band of isolated molecules in PMMA and of chlorophyll monosolvates in MTHF as well as the Qx and the Qy bands of chlorophyll disolvates in MTHF can be identified unequivocally in the fluorescence spectra.
Notizen:Schwingungseigenschaften des TeO4
2- -Ions/ Vibrational Properties of the TeO4
2--Ion
Authors: Baran Enrique J. 
Published: February 2015

Abstract
A complete assignment of the fundamental vibrations of the tetrahedral TeO4
2- ion is proposed and its principal force constants have been calculated using the modified valence force field. Mean amplitudes of vibration and bond orders are also estimated. The results are briefly discussed and some comparisons with related species are made.
Notizen:Electron Diffraction Investigation of the Molecular Structure of Trifluoromethyl Sulphonyl Chloride
Authors: Brunvoll Jon , Hargittai István , Kolonits Mária 
Published: February 2015

Abstract
An electron diffraction investigation yielded the following geometric parameters for trifluoromethyl sulphonyl chloride rg(C-F ) 1.326(4), rg(S=0 ) 1.416(7), rg(S-Cl) 2.016(5), rg(S-C) 1.857(6) Å, ∢ O= S - C 108.3(7)°, ∢ C-S-Cl 98.7(4)°, ∢ O = S = O 122.4(10),° ∢ O = S - Cl 108.3(3)°, ∢ F -C-F 109.9(3)°. The S - C bond is in CF3SO2Cl by almost 0.1 Å longer than in CH3SO2Cl.
Notizen:Einige Bemerkungen zur Stabilität von WO2F2 / Remark on the stability of WO2F2
Authors: Bruijn J. de , Dettingmeijer J. H. 
Published: February 2015

Abstract
Based on equilibrium calculations on the W-O-F system [6], in which WO2F2 was found to be the predominant low temperature species, an attempt was made to synthesize WO2F2 from WO2 + NF3.
However, yields of WOF4 instead of WO2F2 were obtained. This discrepancy between theory and experiment is shown to be due to an error in the estimation of the thermodynamic data of WO2F2 [1].
General Formulation of the (111,1̄11) Neutron Three Beam Case
Authors: Treimer W. 
Published: February 2015

Abstract
A formalism developed in a previous paper [1] is now applied in a general way to the special three beam case (111, 1̄11). The restriction for the incoming wave to be located in the symmetry plane is abolished. The individual behavior of the dispersion surfaces and reflection curves are determined and discussed.
Theoretical Study of Time Correlation Functions in a Discrete Chaotic Process
Authors: Fujisaka Hirokazu , Yamada Tomoji 
Published: February 2015

Abstract
One-dimensional discrete chaotic processes are studied from a statistical-dynamical point of view. A set of equations which describe the behavior of the time correlation functions is derived with the aid of Mori’s projector formalism. A condition under which a process is Markoffian is obtained, and an approximate method is developed for a non-Markoffian process. As an illustration, a time correlation function for a simple system is calculated and the comparison with results of computer simulations is made. The relation between the instability of a trajectory and the characteristic time of chaotic motions is also discussed.
Effect of Conductivity on Magneto-Gravitational Instability and Suspended Particles
Authors: Chhajlani R. K. , Vashistha P. , Bhand S. C. 
Published: February 2015

Abstract
The self gravitational instability of an infinite homogeneous magnetized gas-particle medium in the presence of suspended particles is investigated. The conductivity of the medium is assumed to be finite. The dispersion relation is obtained for such a medium. It is found that in the presence of suspended particles a sufficient condition of instability is obtained by Jeans’ criterion for a self gravitating magnetized conducting gas-particle medium.
“Constant-Volume Alloy” Formulation of Enthalpy of Mixing for Metallic Systems
Authors: Leribaux H. R. , Desre P. J. 
Published: February 2015

Abstract
We present an exact statistical thermodynamic expression for the partial enthalpy of mixing for metals which avoids the problems of evaluating the large internal energy of the pure metals from the plasma state. This method is applied to the homovalent alloys Al-Ga, Al-In and Al-Tl. The results show clearly the tendency towards a critical mixing point in these systems when using a pseudopotential theory for these metals. An estimate for the critical point of the Al-Tl system and reasonably correct values for the partial enthalpies at infinite dilution are obtained.
Microwave Spectra of Dimethylether (CH3)2O and (CD3)2O in Excited Torsional States
Authors: Lutz H. , Dreizler H. 
Published: February 2015

Abstract
The rotational spectra of the torsional excited states v̅n = 11,12,21, 22, 23 have been measured and assigned. The torsional fine structure was used to determine the coefficients V3 and V' 12 of the hindering potential. For (CH3)2O : V3 = 2618 ± 4 cal/mole, V'12 = 18 ± 8 cal/mole, for (CD3)2O : V3 = 2572 ± 6 cal/mole, V'12 = 29 ± 12 cal/mole, V12 was correlated to V3 .
A Cluster Expansion Formalism for Direct Calculation of Ionisation Potential and Excitation Energy of Many Electron Systems Using H-F Ground State as Vacuum
Authors: Mukherjee D. , Mukhopadhyay A. , Moitra R. K. 
Published: February 2015

Abstract
In this note, the authors’ recently developed non-perturbative open-shell theory is adapted for direct calculation o f ionisation potential and excitation energy of m any-electron systems. The H -F ground state is used as the “vacuum ” or “ core” in order to achieve a transparent separation o f the ground state energy. An application to a simple 4 π-electron system is discussed as an illustration o f the workability of the theory.
Measurement of Fluorescence Lifetimes of Coumarin Laser Dyes with a Mode-Locked Krypton Ion Laser
Authors: Richardson J. H. , Steinmetz L. L. , Deutscher S. B. , Bookless W. A. , Schmelzinger W. L. 
Published: February 2015

Abstract
The fluorescence lifetime of four coumarin laser dyes (C-7, C-30, C-102, and C-120) were measured in three different solvents (methanol, ethanol and water) a t dilute and lasing concentrations. The lifetime generally decreases for the more hydrophobic dyes as the solvent polarity increases. There is little change with concentration due to the large Stokes shift.
Properties of [N,N′-di(n-propyl)-4,4′-bipyridylium]2+ (7,7,8,8,-Tetracyanoquinodimethane)4
2–
Authors: Ashwell G. J. , Diaconu I. , Eley D. D. , Wallwork S. C. , Willis M. R. 
Published: February 2015

Abstract
The crystal structure and electrical properties of [N,N′-di(n-propyl)-4,4′-bipyridylium]2+ -(7,7,8,8-tetracyanoquinodimethane)4
2-, (DPrBP)2+(TCNQ)4
2-, are reported. The complex is monoclinic with the space group P21/c and lattice constants a = 13.334(1), b = 25.954(3), c = 7.877(1) Å, β = 93.66°, Z = 2. The single crystal dc resistivities at 300 K along a, b and c are 3300, 200 and 800 Ω cm respectively with activation energies of 0.36, 0.22 and 0.30 eV. The existence of a hopping mechanism in addition to a frequency independent conduction process is indicated by a. c. conductivity data obtained on a compressed disc between 10 and 105 Hz.
Optical and ODMR Investigations of the Lowest Excited Triplet State of Dinaphtho-(2′.3′:1.2); (2″.3″:6.7)-pyrene
Authors: Bräuchle Chr. , Kabza H. , Voitländer J. 
Published: February 2015

Abstract
On the basis of the phosphorescence spectrum of dinaphtho-(2′.3′:1.2); (2″.3″:6.7)-pyrene in n-dodecane (Shpolskii matrix) at T = 1.3 K a site and vibrational analysis was performed. With the help of ODMR measurements the symmetries of the vibrational bands were determined. In this way for most of the normal modes an assignment of the type of vibration became feasible. Because of their different zero-field splittings (ZFS) five sites could be identified. The signs of the ZFS parameters as well as the kinetic rate constants of population and depopulation of the zero-field levels (ZFL) of T1 were determined. Like the ZFS the kinetic rate constants too were different for each site reflecting different interaction of the molecules with the host matrix. Radiative and radiationless processes are discussed in terms of spin-orbit coupling (SOC).
Clusius’ Separation Column as a Reactor to Produce Highly Concentrated Hydrogen
Authors: Hirota Kozo , Aizawa Kazuo , Nishizawa Tsuneyuki 
Published: February 2015

Abstract
A Clusius’ separation column of hot wall catalytic activity was applied as a reactor to produce highly concentrated hydrogen. Satisfactory results are obtained in the decomposition of hydrogen sulfide and the conversion of carbon monoxide with water.
The Langmuir-Hinshelwood Reaction between Oxygen and CO at Ir(111) Surfaces
Authors: Küppers J. , Plagge A. 
Published: February 2015

Abstract
The reaction of oxygen and CO to form CO2 has been investigated using an Ir (111) surface as an acting catalyst. Both instationary and stationary reaction processes have been established via separate gas exposing techniques. The instationary reaction process, achieved from coadsorbed CO and O which per se is an LH reaction is found to be controlled by an apparent activation energy of 10.7 kcal/mole. The stationary reaction with both CO and O2 continuously present in the gas phase has been simulated using a proper computer program, involving both LH and ER reaction steps. By comparison with experimental results, close agreement is found when ruling out any ER reaction step from the reaction path.
δ13C Record in an Undisturbed Forest Soil
Authors: Schleser G. H. , Pohling R. , Meyer B. 
Published: February 2015

Abstract

13C/12C variations of organic carbon have been investigated in an undisturbed forest soil with perched surface water. The measurements reveal a very distinct decrease of the 13C-content with increasing depth of the soil horizons. Within 20 cm the δ13C-value is depleted by 1.5/0
00. At present it is however not possible to verify, whether this behaviour is characteristic for undisturbed soils in general.
Die spezifische Wärme der zweiten Relaxationsstufe der Essigsäure
Authors: Asenbaum A. 
Published: February 2015

Abstract
The The relaxation time σv in liquid acetic acid was measured by Brillouin scattering for temperatures in the range between 20 °C and 60 °C. At 20 °C σv is equal to 56,2 ps corresponding to a relaxation frequency fR2 of 2,51 GHz. fR2 is increasing with increasing temperature and there-fore shows the same behaviour as the first relaxation frequency fR1 measured by Lamb and Pinkerton. From σv and the hypersound-velocity and hypersound damping data the relaxing specific heat ci2 has been calculated (ci2 = 0,125 cal/g K at 20 °C). In contrast to the specific heat ci1 of the first relaxing step of acetic acid ci2 seems to be temperature independent within the experimental error
Polarized Crystal Absorption Spectra of Pd(II) and Pt(II) Tetrahalo and Tetrathiocyanato Complexes
Authors: Tuszynski W. , Gliemann G. 
Published: February 2015

Abstract
Single crystal absorption spectra of tetrachloro, tetrabromo, and tetrathiocyanato complexes of Pd(II) and Pt(II) have been measured in the visible and near-ultraviolet region at temperatures between 10 K and 295 K. A spectral assignment of the observed d-d transitions based on ligand field theoretical calculations including electron-electron interaction and spin-orbit coupling is proposed which is consistent for all the systems investigated
Laser Power Noise Measurements on a Cataphoretic He-Cd+ Laser
Authors: Neiger M. , Nemec V. 
Published: February 2015

Abstract
Laser power noise has been measured on a cataphoretic He-Cd+ laser. Care was taken especially to stabilize the temperature of the external cadmium source and to thermally insulate the discharge capillary. It was found that high and low noise operating regions exist with noise values below 1% rms at power levels up to 80% of the maximum obtainable ones
Unitarization in Nonlinear Spinor Field Quantum Theory
Authors: Stumpf H. , Scheerer K. 
Published: February 2015

Abstract
Heisenberg performed a dipole ghost regularization of the Lee-model and a subsequent uni-tarization of the corresponding state space. If this method is transferred to the relativistic non-linear spinor field model, insoluble difficulties appear as long as no explicit state representations are used. In preceding papers such state representations for the spinor field have been derived and in the present paper it is demonstrated how they can be successfully used to perform the relativistic analogon to Heisenberg's Lee-model unitarization. As the state representations have to be derived by construction, the method is demonstrated for the two particle fermion sector which is sufficiently well-known.
Schwingungsspektrum von CSFCl Vollständiger Satz von Anharmonizitätskonstanten; harmonische Schwingungsfre- quenzen ; korrigiertes harmonisches inneres Kraftfeld / Vibration Spectrum of CSFCl
Authors: Hamm R. 
Published: February 2015

Abstract
The measurement of the infrared spectrum of CSFCl over a large spectral range from 300 cm -1 to 4000 cm -1 was done with a special cell allowing a path-length of up to 20 m. In that way it was possible to obtain a full set of anharmonicity constants by exploring combination and over-tone bands. Hereby the vibration frequencies of the fundamentals could be corrected for anharmonicity. The corrected values of the main species and of a further isotopic species were used to calculate the internal harmonic force field. The harmonic vibration correction terms needed for the determination of the rz-structure turned out to be changed only by 1% as com-pared with those values that were infered from a preliminary force field formerly.
Ground State Wave Function and Superexchange Interaction in CuCl2 · 2NC 5 H 5
Authors: Amoretti G. , Varacca V. , Vera A. 
Published: February 2015

Abstract
A model of superexchange, which takes into account the contributions of the polar states, is applied to the case of CuCl2 · 2 NC5H5. As pointed out in a preceding paper, the experimental exchange constant Jeff can be fitted in a reasonable range of parameters of the ground state wave function, which, on the other hand, is tested by means of ESR experimental data. The results are compared with those obtained for CuCl2 · 2 H2O and the approximations introduced are discussed and justified.
Spin-Gitter-Relaxationszeit T1 von Nitrilkohlenstoffen / Spin-Lattice-Relaxation Time T1 of Nitrile Carbon-atoms
Authors: Sterk H. , Kalcher J. , Kollenz G. , Waldenberger H. 
Published: February 2015

Abstract
It is shown that in almost all nitrile carbon-atoms T1 depends first of all on the inter-and/or intramolecular dipol-dipol-relaxation mechanism. Only acetonitrile, as is already known, shows a remarkable dependence on the spin-rotation-relaxation mechanism. This influence is strongly decreasing with an increasing number of atoms, specially hydrogen atoms, in the molecule. The significance of the correlation time r is discussed extensively and the experimental results are verified by calculation of T1 using the viscosity and the inertial moments as parameters.
On the Deconvolution of Measured Curves with Measured Apparatus Functions and the Information Content of Curves
Authors: Hühnermann H. , Menzel N. 
Published: February 2015

Abstract
A general problem in natural science is the analysis of experimental curves, which are quite often distorted due to the measuring devices. However, in some cases the apparatus function can be measured separately so that one can hope to restore the original curve by means of a suited mathematical procedure. Based on experimental examples taken from atomic physics and without complicated mathematical formalism, we show possibilities and limitations of the deconvolution of measured curves with measured apparatus functions. The choice of the Fourier transformation algorithm makes it possible to compute the information content of curves quite easily. This may be used to optimize the performance of an experiment.
Winfree Meandering in a 2-Dimensional 2-Variable Excitable Medium
Authors: Rössler . E. , Kahlert C. 
Published: February 2015

Abstract
Two-dimensional excitable media, for example the excitable version of the Belousov-Zhabotin-sky reaction, are capable of forming spiral-shaped self-sustaining rotating wave patterns (rotors). In order to explain Winfree's experimental observation of an irregular "meandering" of the rotor's core region, we present a numerical simulation of a continuous, two-variable excitable medium in two space dimensions. Two phenomena occur: 1) an irregular motion of the rotor's core; 2) a non-stationary peak inside the core region. Thus, "meandering" is obtained, together with a new phenomenon, the "peak". A sufficient condition for both phenomena is that the underlying (local) system be stiff, that is, admit two time scales for its approximate description. In this case, (1) the "reaching distance" of diffusion is small as compared with the core's radius, and (2) rotation symmetry of the core implies a gradation in local frequencies (increase toward the center), supposing radial decoupling. We propose that both constraints act together to induce a spontaneous breakdown of rotation symmetry under an increase of stiffness. Immediately (or soon) thereafter, the core is no longer synchronized by the wave circling around it; instead, excitation from the surrounding wave penetrates the core along a new path from time to time, causing a non-repetitive short-cut.
Electron Energy Distribution Functions of Hydrogen: The Effect of Superelastic Vibrational Collisions and of the Dissociation Process
Authors: Capitelli M. , Dilonardo M. 
Published: February 2015

Abstract
Electron energy distribution functions (EDF) of molecular H2 have been calculated by numerically solving the Boltzmann equation including all the inelastic processes with the addition of superelastic vibrational collisions and of the hydrogen atoms coming from the dissociation process. The population densities of the vibrational levels have been obtained both by assuming a Boltz-mann population at a vibrational temperature different from the translational one and by solving a system of vibrational master equations coupled to the Boltzmann equation.
The results, which have been compared with those corresponding to a vibrationally cold molecular gas, show that the inclusion of superelastic collisions and of the parent atoms affects the EDF tails without strongly modifying the EDF bulk. As a consequence the quantities affected by the EDF bulk, such as average and characteristic energies, drift velocity, 0-1 vibrational excitation rate are not too much affected by the inclusion of superelastic vibrational collisions and of parent atoms, while a strong influence is observed on the dissociation and ionization rate coefficients which depend on the EDF tail.
Calculated dissociation rates, obtained by EDF's which take into account both the presence of vibrationally excited molecules and hydrogen atoms, are in satisfactory agreement with experimental results.