bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensitivity analysis of piecewise linear vibration
isolator with dual rate spring and damper
Authors: Pogorilyi Oleksandr , Trivailo Pavel , Fard Mohammad , Jazar Reza N.
Published: February 2015

In this paper the exact frequency response of
symmetric piecewise linear vibration isolator has been revised
and reviewed. The frequency response of the system
is calculated and detailed sensitivity analysis is presented.
The method of obtaining the exact frequency response of
the isolator is based on combining together the liner solutions
of different segments within the cycle of motion of
the system. In this paper set of graphs for different parameters
of the system that illustrates the sensitivity of the system
have been provided. The analysis of the impact of parameters
of the system on its behavior has been presented.
The sensitivity analysis is required to be able to determine
the working domain of the parameters. Jump avoidance
and peak amplitude minimization are the main aspects of
parameter working domain.
Influence of High Frequency Electric Field on the Dispersion of Ion-Acoustic Waves in Plasma
Authors: Turky A. , Čerček M. , Stefan R. Tavzes J.
Published: February 2015

The modification of the ion-acoustic wave dispersion under the action of a high frequency electric field was studied experimentally, the wave propagating along and against the plasma stream. The frequency of the field amounted to approximately half the electron plasma frequency. It was found that the phase velocity of the ion wave and the plasma drift velocity decrease as the effective high frequency field power increases
Interpretation der Absorptionsspektren von Aza- und Azinium-substituierten Anthracenen / The Interpretation of Absorption Spectra of Aza- and Azinium-Substituted Anthracenes
Authors: Bendig J. , Kreysig D. , Kawski A.
Published: February 2015

The absorption spectra of the 3 isomeric aza- and the 4 isomeric azinium-anthracenes are discussed on the basis of the absorption anisotropy, the oscillator strenght and the fluorescence decay times. The influence of endocyclic substitution depends on the position of the aza- and aziniumgroup, respectively. In the case of acridine, acridinium, benzo[g]quinolinium and benzo[f]- isoquinolinium the S0 → S2-transition is observable. The spectra of benzo[g]quinoline, benzo[f]- isoquinoline and acridizinium are similar to those of anthracene
14N Nuclear Quadrupole Coupling in Heterocyclic Compounds, Part 2. A Comparison of ab initio Calculations and Experimental Results for the Azoles and Azines
Authors: Palmer Michael H. , Simpson Isobel , Findlay Robert H.
Published: February 2015

Ab initio calculations of double zeta quality have been reported for the conjugated 5- and 6- membered ring heterocycles containing NH and NMe groups. The electric field gradients were calculated and the derived nuclear quadrupole coupling constants (NQCC) compared, both in magnitude and direction, with those obtained by microwave spectroscopy and by nuclear quadrupole resonance. A comparison of the results with those of the corresponding O- and S-heterocycles, and with acyclic compounds has been given, and it was shown that aromaticity considerations were of no relevance to the NQCC values at pyridine-like N; planarity of the N atom at N-1 in the systems 2 c-9 c is responsible for the very low magnitude of Xπ, and this is clearly associated with the level of π-donation from N-1; this is a function of position of the other ring N atoms, and appears to become saturated as the ring positions become predominantly N. In particular three contiguous N atoms seem to have less effect than two N atoms
Production of Polycrystalline n-TiO2-Layers for Photoelectrodiemical Purpose
Authors: Hartig K. J. , Lichtscheidl J. , Getoff N.
Published: February 2015

The preparation of highly photoactive, polycrystalline n-TiO2-semiconductors by thermochemical oxidation of Titanium metal sheets was investigated systematically. The optimum temperature in an oxygen atmosphere was found to be between 550 °C and 650 °C for a period of 10-30 min. Careful etching of the Titanium surface prior to oxidation is a decisive step in the production process. The growth, adhesion on the substrate and photoefficiency of the TiO2- crystals were studied under various experimental conditions. TiO2-layers prepared under optimum conditions showed a photocurrent higher than 2 mA • cm-2 in 0.1 mol • dm-3 KCl as electrolyte and about 6 mA • cm-2 in 1 mol • dm-3 KOH, respectively. The overall energy conversion was ≅ 3.5%
Bestimmung partieller photochemisdier Quantenausbeuten iiber kombinierte Absorptions- und Fluoreszenzmessung / On the Determination of Partial Photochemical Quantum Yields by Combined Absorbance and Fluorescence Measurement
Authors: Frank R. , Gauglitz G.
Published: February 2015

A combined automatic set up for the measurement of fluorescence and absorbance is described. The absorbance at irradiation wavelength E' and a fluorescence reaction spectrum are measured continously and simultaneously. Even for solutions with high concentrations up to E'>1, the fluorescence intensity can be corrected for. By this method the photodegradation of fluorescent dyes was examined. Because only a few of the degradation products fluoresce, the determination of kinetic parameters is easier than from absorbance measurements. The method gave good results for laser dyes using even high concentrations (E'> 1), with less calculatory expenditure and smaller standard deviation in comparison to the evaluation of absorbance measurements only
Exploded Points
Authors: Gurel Okan
Published: February 2015

A new concept of a mathematical object of zero dimension, an exploded point, is introduced. The dimension used is defined on the basis of the functional characteristics of the system, thus it may be referred to as f-dimension. A stability index is also defined for the mathematical objects including exploded points, which can be related to the f-dimension. It is shown that the mathematical object exhibited by the Lorenz system after the second bifurcation is such a point. A recursive formula based on the definition of the exploded point
Comments on the Mean Diffusion Length of Luminescent Molecules in Solutions
Authors: Bojarski C.
Published: February 2015

The effect of concentration of donor and acceptor molecules on the mean diffusion length in solutions is discussed
Strange Attractors, Chaotic Behavior, and Information Flow
Authors: Shaw Robert
Published: February 2015

Simple system equations displaying turbulent behavior are reviewed in the light of information theory. It is argued that a physical implementation of such equations is capable of acting as an information source, bringing into the macroscopic variables information not implicit in initial conditions. The average rate of information production λ̄ is a system state function, and is given for simple cases by a "Liapunov characteristic exponent", developed by Oseledec. The transition of a system from laminar to turbulent behavior is understandable in terms of the change of λ̄ from negative to positive, corresponding to the change of the system from an information sink to a source. The new information of turbulent systems precludes predictability past a certain time; when new information accumulates to displace the initial data, the system is undetermined.

The observed geometry of strange attractors is seen to arise naturally from a rule allowing joining but not splitting of trajectories in phase space. The phenomenology of strange attractors in three dimensions is discussed, and a basis for their classification suggested. A comment is made on the commonplace occurrence of information producing systems in the real world, and on their possible relation to 1/f noise
On the Inversion of the Linearized Collision Operator
Authors: Weinert Ulrich
Published: February 2015

Some features are discussed in connection with the representation of the linearized Boltzmann collision operator and its inversion. It is shown that under certain assumptions the inverse operator can be given explicitly as an integral kernel function.
Ultraschall-Geschwindigkeit und-Absorption in Bi-In-Schmelzen /Ultrasonic Velocity and Absorption in Bi-In-melts
Authors: Bek R. , Steeb S.
Published: February 2015

Using the pulse-echo method the ultrasonic velocity and absorption was measured with Bi-In-melts in the temperature range from liquidus up to more than 600 °C. The frequencies used reached from 10 MHz up to 130 MHz. Within the experimental accuracy no frequency dependence of the absorption coefficient α/f2 could be detected. An excess absorption can be observed, which for the molten elements can be explained by fluctuations of the packing density. For the molten alloys additionally concentration fluctuations play an important role. Thus an understanding of the temperature dependency of the ultrasonic velocity and absorption can be achieved.
X-Ray and Neutron Diffraction Studies on Amorphous Transitionmetal—Boron Alloys (Fe-B,Co-B,Ni-B)
Authors: Lamparter P. , Nold E. , Rainer-Harbach G. , Grallath E. , Steeb S.
Published: February 2015

The atomic-scale structure of the amorphous metallic alloys Fe80B20, Co81·5B18·5, and Ni81·5B18·5 was investigated by X-ray- and neutron-diffraction covering a wide range of the ratio (fmetal/fboron) of the scattering factors of both components. The structure factors S (q) show a pronounced dependence on the ratio fmetal/fboron . In the cases of a small ratio an additional peak near q = 21.5 nm-1 appears in the structure factors from which a definite distance between B-B atoms, which are separated by metal atoms, is deduced. The corresponding structure factors show only weak oscillations in the range of the second and third maxima, which are followed by increased amplitudes at larger q's.

By Fourier-transformation radial distribution curves were evaluated, from which the distances between the metal-metal-, the metal-boron-, and the boron-boron-atoms and the coordination numbers are extracted. From the splitted first maximum of the radial distribution function in the cases of small ratio fmetal/fboron also partial coordination numbers could be obtained. The results suggest some kind of short range order between the metal and the boron atoms.
Ober Phaseniibergange von Ammonium-Alkali-Jodiden und verwandten Halogeniden / Phase Transitions of Ammonium-alkali Iodides and Related Halides
Authors: Brauer Peter
Published: February 2015

The investigation of the order-disorder transitions of the ammonium-chlorides and -bromides, in which some of the NH4
+ are replaced by Cs+, Rb+ or K+, is extended to the corresponding iodides using birefringence and differential thermal analysis. As the temperature range of the martensitic transition (Pm 3 m↔Fm 3 m) is now overlapping the temperature range of the orderdisorder transitions, the former must be included in the measurements. The results allowing an overlook are discussed using the work of Garland, Lushington, and Leung [5]
On the Derivation of Strong and Electro-weak Interactions in Functional Quantum Theory of the Nonlinear Spinor Field as a Lepton-hadron Model with Quark-confinement
Authors: Stumpf H.
Published: February 2015

In preceding papers the nonlinear spinor field with Heisenberg's dipole regularization was interpreted as a lepton-quark system. In this paper it is demonstrated that this model is able to produce electro-weak as well as strong interactions. For the analytical derivation of these interactions, in Section 1 an improved calculation technique for scattering functionals is developed which corresponds to an interaction representation of relativistic quantum fields with inclusion of bound states, and which is suited for a comparison of its results with conventional field theories, in particular gauge theories. In Section 2 the projection technique from the spinor field into the lepton-quark representation is discussed in detail. The principle which allows the derivation of the various interactions consists in the calculation and incorporation of universal (local) bosons and non-universal (non-local) bosons occuring as bound states of the spinor field, resp., leptonquark fields, into the scattering functional equation. This is performed for local bosons in Section 1 and for non-local bosons in Section 3. In Section 4 it is shown that a subsequent unitarization which corresponds to quark confinement leads to selection rules for lepton-baryon processes which qualitatively correspond to those of grand unification gauge theories. Numerical calculations will be given in subsequent papers
The Temperature Dependence of the Viscosity of Suspensions of Polystyrene Latices in LiCl Solutions
Authors: Bonincontro A. , Cametti C. , Di Biasio A.
Published: February 2015

The viscosities of suspensions of polystyrene particles in aqueous LiCl solutions (about 3.5 · 10-4 M) at temperatures from 0 to 60 °C were measured and fitted to relations of the form η = η0(1+K1ϕ+K2ϕ2)i where ϕ is the volume fraction of the particles.

In contradiction to existing theories the coefficients K1 and K2 were found to be temperature dependent
Influence of Dissolved Silver on the Electrical Conductivity and the Optical Spectra of the Molten Mixtures AgCl1-xBrx
Authors: Schwind A. F. , Vötsch R. , Weil K. G.
Published: February 2015

Electrical conductivities of molten mixtures AgCl1-x-Brx were measured at different temperatures. No influence of dissolved silver on the conductivity could be detected. The apparent energy of activation does not depend linearly on x. The optical spectra of molten mixtures AgCl1-x-Brx show a flat absorption edge which can be treated by the formalism of Urbach. The energy gap of the indirect transition can be evaluated as a function of x. In metal-containing mixtures, the edge is slightly red shifted. This red shift can be attributed to a new absorbing species. The results make it likely that the interaction between the dissolved metal and the melt is of the charge transfer type
Improved Construction of Coupling Operator
Authors: Ishikawa Yasuyuki
Published: February 2015

The construction of the coupling operator given by Adams is examined from the standpoint of SCF convergeney. A unified, hermitian coupling operator is derived by taking into account optimum mixing for the pairs of occupied orbitals as well as the correct variational conditions
The Maximum of the Conductivity of an Ionic Melt from MD Simulations at Various Temperatures
Authors: Okada Isao , Takagi Ryuzo
Published: February 2015

Molecular dynamics simulations of molten TlCl are performed at 7 temperatures between 800 and 2600 K. The self-exchange velocity of neighbouring unlike ions divided by the molar volume, a quantity corresponding to the specific conductivity, is found to have a maximum as a function of temperature. The reason for the existence of the maximum is discussed
Internal Mobilities in (Na-Rb)NO3 Melts
Authors: Okada Isao , Takagi Ryuzo , Kawamura Kazutaka
Published: February 2015

Internal mobility ratios in melts of the system (Na-Rb)NO3 have been measured with the Klemm method at various temperatures and compositions. The internal mobilities have been calculated from these and the available data on densities and conductivities. The Chemla effect has been observed. For NaNO3 concentrations > 10 mol %, the internal mobility of the Na+ ions obeys the formula bNa = [A/(V - V0)] exp(- E/RT). where V is the molar volume and V° is slightly temperature dependent. For NaNO3 concentrations < 10 mol %, bNa becomes smaller than expected from the formula. The internal mobility of the Rb+ ions also obeys such a formula at higher temperatures. At lower temperatures it in, like that of the Cs+ ions, a function of the mole fraction and independent of the kind of coions
Kraftkonstanten von N-Chlor-Dichlormethylenimin Cl—N=CCl2 / Force Constants of Cl—N=CCl2
Authors: Kalcher K. , Kosmus W.
Published: February 2015

GVFF and ab initio calculations are reported for ClNCCl2. The force constants for the Cl-N and C-Cl bonds show significantly higher values than those of similar compounds, fCN is lower. The charge distribution obtained by ab initio calculations support these results
A New Explanation for the Hexagonal Shape of Lunar Craters
Authors: Dijk Th. van , Kistemaker J.
Published: February 2015

If a mechanical shock-wave expands symmetrically in a two-dimensional non-isotropic medium, then the amplitude of the radial displacements is directionally dependent. This has been demonstrated by a system of 1400 hexagonal plastic pillars, simulating the impact of a 10 km size meteorite on a frozen 50 km thick basalt crust in the earliest phase of the Moon’s life
Simple Analytic Expressions for the Total Cross Section for γ-e Pair Production
Authors: Haug Eberhard
Published: February 2015

The total cross section for pair production by photons in the field of free electrons is fitted to simple analytic expressions in four intervals of the incident photon energy which cover the whole range between threshold and infinity
O Functional Quantum Mechanics and the Equivalence with a Product of Schrödinger Problems
Authors: Wahl F. , Feist W.
Published: February 2015

The New Tamm-Dancoff procedure consists of three main parts: an expansion for pairs of states with respect to a non-orthogonal base, a cut-off approximation for this expansion, and a transformation with respect to a new reference state. In this paper we treat part one and two. It is shown that the NTD-procedure is equivalent to the tensor product of the original Schrödinger problem and its conjugate problem. The occurring nonlinear transformation is examined and the cut-off is discussed.
Messung des Chapman-Jouguet-Druckes mit Röntgen-Absorption
Authors: Hollenberg K. , Kleinhanß H.-R. , Reiling G.
Published: February 2015

The Chapman Jouguet pressure of some high explosives is measured by X-ray absorption giving the density behind the detonation front. An accuracy of 2 - 3% was achieved in the pressure range of 200 kbar. The pressures are considerably lower than comparable results of other authors obtained by the free surface velocity method or similar techniques.
A ALow-Energy Direct Channel Regge-pole Approach to α-C12Elastic Scattering .I
Authors: Majumdar D. , Chowdhury A. Roy , Roy T.
Published: February 2015

Differential scattering cross-sections for the elastic scattering of α by C12 at laboratory bombarding energies from 11.0 to 16.0 MeV have been evaluated in the direct channel Regge-pole formalism, taking into account the contributions from a few nearby dominant excited levels of the compound nucleus O16 and incorporating the background effect. The relevant pole-parameters have also been predicted.
Gleichzeitige Bestimmung von Parametern der Ionosphären-D-Region beim Vorliegen eines negativen Höhengradienten der Elektronenkonzentration
Authors: Muschler W.
Published: February 2015

Preceding papers were concerned with the principles of a wave propagation experiment, which appeared suitable for a simultaneous determination of electron concentration Ne and electron collision frequency v in a magnetoplasma. The complex wave polarization was used being defined by field strength ratios. In former model calculations the electron concentration profile was characterized by exclusively positive height gradients. In this paper considerations are extended to an electron concentration profile with gradient inversion. Calculations on error propagation and wave damping and an estimation of the coupling parameter do not lead to new or serious restrictions in the question of the applicability of the method.
Resonant Interaction of Surface Plasmons with a Dye Monolayer
Authors: Wahling G.
Published: February 2015

Surface plasmons on silver films covered with organic monolayers (dye molecules (S 120) deposited on cadmium arachidate Scheibe or ϳ aggregate) are studied in detail. The optical properties of this system derived from reflection measurements can be described by a rather simple one electron oscillator model. The damping of its eigenfrequency is rather small due to the regular arrangement of the dye molecules. ATR measurements showed a strong influence of this narrow resonance on the dispersion relation of surface plasmons. These observations can be well described by the dielectric function derived from the reflection measurements. The dye molecules are deposited on a cadmium arachidate film of 27 Å thickness. In the case of more than one cadmium arachidate space layer between dye and metal the agreement of observed data with those calculated using the oscillator constants gets worse. This is explained by the decreasing order of the dye molecules in the ^'-aggregates with increasing number of space layers
The Molecular Structure of Benzotrifluoride as Studied by Gas Electron Diffraction
Authors: Schultz György , Hargittai Istvan , Seip Ragnhild
Published: February 2015

The molecular structure of benzotrifluoride has been studied by electron diffraction. The geometry of the carbon ring is essentially regular hexagonal. The bond configuration of the trifluoromethyl group considerably departs from the regular tetrahedral arrangement. The following values were obtained for bond lengths (rg) and bond angles: r(C-C)ring- 139.7 ±0.3 pm (mean value), r(Cmethyl-Cphenyl) = 150.4 ± 0.4 pm, r(C-F) = 134.5 ±0.3 pm, r(C-H) = 109.9 ± 0.5 pm and ∢ C-C-F = 111.9 ± 0.1°. The electron diffraction data are in agreement with nearly free rotation of the -CF3 group around the Cmethyi-Cphenyi axis
A Note on the Throbbing of Glow Discharges in Gases at Low Pressures
Authors: Chaudhri Rafi M. , Zahra Tasneem , Chaudhri M. Munawar
Published: February 2015

The influence of acyclic conjugated branches on the π-electron energy and energy gaps of infinite polymers containing benzene rings is studied applying a graph-theoretical extrapolation scheme. It is found that methylene branches strongly reduce the energy gap of the unmodified polymers.
Dynamical Jahn-Teller Systems: Internal Energy Resonance Structures of Isolated Jahn-Teller Molecules (E-b and T-t System)
Authors: Sigmund E. , Brühl S.
Published: February 2015

The internal energetic transfer processes of an E - b and T - t Jahn-Teller system are con­ sidered. The first system allows an exact description, whereas in the case of the second one ap­ proximations must be introduced in the region of intermediate electron-phonon coupling strengths. The occupation probabilities of the states of the uncoupled systems change with time by virtue of the electron-phonon interaction. The energies are directly related to these occupation probabilities. The resonant nature of the T - t system is reflected in the internal dynamics of the latter.
Voltage-Induced Cholesteric Structure-Transformation in Thin Layers
Authors: Gerber Paul R.
Published: February 2015

o lta g e -In d u c e d C h o le s te r ic S tr u c tu r e -T r a n s f o r m a tio n in T h i n L a y e rs Measurements of various threshold voltages which occur in thin layers of cholesteric liquid crystals with positive dielectric anisotropy under homeotropic wall-alignment conditions are presented. Characteristic times are determined for some of the structure-changing processes which take place under application of electric-field changes. The measurements have been performed for various pitch-to-thickness ratios, and are expressed in empirical formulae.
Lifetime Measurements of AU Excited States of the 4d95 p Configuration in the Pd-I Spectrum
Authors: Baumann M. , Liening H. , Loos H.
Published: February 2015

The lifetimes for the 4d95p configuration have been determined by zero field level crossing technique. The re­ sults are (in nsec):
On the Ground State of H-
Authors: Gupta Uday Vanu Das , Saha Subal Chandra , Sengupta Sankar
Published: February 2015

A simple and effective method is described to calculate the ground state energy of H~ starting with the Hartree Fock wavefunction. The expectation values of the opera­ tors 〈r1 • r2〉, 〈r1
n + r2
n〉 and 〈p1 • p2〉 can be estimated easily with the present procedure. Oscillator strength sums S(k) for k= -1,0, 1 are also evaluated.
Collision Broadening and Shift of the 535.0 nm Tl Line Accompanying the Photodissociation of Thallium Iodide Perturbed by Noble Gases Part II: Effects due to He, Ne and Ar
Authors: Lisicki E. , Bielski A. , Szudy J.
Published: February 2015

The broadening and shift of the 535.0 nm thallium line resulting from the photodissociation of thallium iodide perturbed by helium, neon and argon were investigated at low densities using a photoelectric Fabry-Perot interferometer. The Doppler and collision broadening components of the line profiles have been determined. Linear variations of both the Lorentzian half-width and the shift of the line with the perturbing gas density were found and interpreted in terms of Van der Waals and Lennard-Jones potentials.
The Instability of Molecules in Laser Field and Isotope Separation
Authors: Li Ke-hsueh
Published: February 2015

In the present paper the nonlinear differential equation describing the selective decomposition of a molecule as an unimolecular reaction has be deduced from the usual time dependent semi-classical Schroedinger Equation. The selective conditions for the instability of a molecule are discussed. The thresholds of the required laser intensities for ICl and HCl diatomic molecules are estimated respectively, where one type of isotope molecules ought to be decomposed for hundred per cent in a laser pulse for different pulse widths. And possibly selective decomposition of the molecule without permanent dipole moment by Raman process is also discussed briefly.
Intramolecular Electron Transfer in Nonconjugated Polyenes
Authors: Böhm Michael C.
Published: February 2015

The probability of hole-propagation of initially prepared vacancies in 1,5-hexadiene (1) and 1,6-heptadiene (2) as well as the transfer mechanisms in 1 and 2 are studied by means of timedependent perturbation theory. Times of equibrilation of about 10-15 sec are calculated. Local perturbations in the π moieties are efficiently transmitted via CH-σ states while CC-σ functions and the direct transfer channel are less important. The theoretical key step consist in an unitary transformation of the canonical molecular orbitals (CMO's) with the diagonal Fock operator into a set of one-electron states forming a transport-type Fockian, FHT, where only a few matrix elements (between the evoluting orbitals and a set of messenger states) differ from zero.
The Role of Polarizabilities in the Fluorescence Behaviour of 4-cyano-N,N-dimethylaniline
Authors: Baumann Wolfram
Published: February 2015

The effect of an external electric field on the absorption and the double fluorescence of 4-cyano-N,N-dimethylaniline can be understood, taking into account reaction field induced polarizability effects. If a TICT state conformation emits the a-fiuorescence in dioxane, the permanent dipole moment in this state is only slightly larger than in the equilibrium ground state.
Structure Investigations on Se1-xTex Melts by Neutron Scattering and X-ray Diffraction
Authors: Hoyer W. , Kunsch B. , Suda M. , Wieser E.
Published: February 2015

Neutron scattering results on Se1-xTex melts (x = 0.3, 0.6, 0.8) obtained at 460 °C are combined with earlier X-ray diffraction data. The behaviour of the number and distance of nearest neighbours is discussed with respect to chemical short-range order and transition from twofold to three-fold coordination. For Se70Te30 the radial concentration correlation function 4πr2 ρcc(r) has been evaluated. It shows clearly the preferred formation of unlike pairs (Se-Te) within the chains.
X-ray Three Beam Cases and the Influence of Lattice Defects
Authors: Scherz W. , Hildebrandt G.
Published: February 2015

The three beam cases {111, 1̅11; 200} (Case I) and {1̅1̅1, III; 220} (Case II) in germanium were examined with CuKα1 radiation from a bent quartz monochromator crystal. For the intensity relation I0/(IL + IM), excellent agreement with previous measurements (Uebach) resulted for Case I; small deviations from a calculated value could be explained by theoretical arguments, considering the crystal as slightly imperfect. In Case II, which reacted more sensitively upon lattice defects, these deviations were much larger and in an unexpected direction. A first attempt of a "Three Beam Lang Topography" is reported.
On the Order-Disorder Phase Transformation of Anilinium Halides. III.
Authors: Fecher Gerhard , Weiss Alarich , Joswig Werner , Fuess Hartmut
Published: February 2015

The crystal structure of the high temperature phase of anilinium bromide, C6H5NH3
⊕Br⊖ , was studied by X-ray and neutron diffraction at T = 343 K. The refinement supports disordered positions of the -NH3
⊕ group. A split-atom model is proposed which includes disorder of the benzene ring. The thermal parameters, hydrogen bond distances, and other experimental data (NMR, NQR, inelastic neutron scattering) are in accordance with this model.
Molecular Constants of Some Alkali Metal Halide Dimers by Kinetic Constants Method
Authors: Manivannan G. , Sengodan V. , Srinivasacharya K. G.
Published: February 2015

The kinetic constants method is employed to obtain a fresh set of potential constants in the case of nine X2Y2 type (D2h symmetry) alkali metal halide dimers. The mean amplitudes of vibration, Coriolis coupling constants, Centrifugal distortion constants and thermodynamic functions are evaluated with the presently obtained potential constants. The results are briefly discussed.
Dark Space ahead of a Shock in Ionized Gas Flows
Authors: Nishida Michio
Published: February 2015

Abstract The dark space, which is formed ahead of a detached shock of a blunt body in a flow of ionized argon, was theoretically investigated, and its mechanism was revealed. The electron energy equation, electron continuity equation and continuity equation of the first excited-level atoms were formulized separatly in a shock layer and in a free stream, and then the free-stream solutions were connected with the shock-layer solutions in such a way that the boundary conditions on the wall of the blunt body are satisfied. The method of solving is described here. The calculations were carried out for the case that atom density is 10 21 particles/m 3 , atom temperature is 500 K, Mach number is 4.5, electron density is 5 X 10 18 particles/m 3 in the free stream and that the wall temperature is 300 K. The results show that the region of the elevated electron temperature exists ahead of the shock and that this elevation causes the decrease in the population densities of excited levels higher than the 5s level. The dark space can be explained as the reduction in the population densities due to the elevation in the electron temperature.
An ESR Study on Oxygen Adsorption and Illumination of Vacuum Treated V2O5/TiO2
Authors: Serwicka E. , Schindler R. N.
Published: February 2015

Oxygen adsorption on vacuum treated TiO2 doped with vanadium results in the formation of O2- species. It is argued that substitutional V3+ ions act as electron donors. The oxygen radicals are stabilized in the neighbourhood of titanium ions. Depending on the oxygen pressure photo-adsorption or photodesorption of oxygen is observed.
The Conformation of trans Benzylidene Aniline from the PCILO and CNDO/S Methods: Role of the three Relevant Bond Lengths —N=CH—
Authors: Jacques Patrice
Published: February 2015

The conformation of trans benzylidene aniline (BA) was investigated, using the PCILO and CNDO/S methods. On the basis of a recent gas phase structure determination, the PCILO method proved very efficient when the valence and dihedral angles were optimized. Moreover, the CNDO/S method establishes clearly the non planarity of BA and gives a quite satisfactory inter-pretation of the UV spectra when appropriate bond lengths are choosen for the -N=CH- skeleton.
On the Derivation of the L.S.Z.-Reduction Formalism in Functional Quantum Theory
Authors: Stumpf H.
Published: February 2015

In functional quantum theory the S-matrix of a quantized relativistic field can be expressed by the scalar product of functional advanced and retarded scattering states. It is shown that for point like particles this scalar product can be reformulated in accordance with the results of the L.S.Z.-reduction technique for the ^-matrix calculation in conventional quantum field theory. The reformulation is performed for the case of relativistic potential scattering but can easily be extended to other cases where the point like particles occur.
Structural Properties of an Aqueous LiI Solution Derived from a Molecular Dynamics Simulation
Authors: Szasz Gy. I. , Heinzinger K. , Riede W. O.
Published: February 2015

In the molecular dynamics simulation of the aqueous LiI solution the ST2 water model was employed and the ions were described as Lennard-Jones spheres with an elementary charge at the center. The basic periodic cube contained 200 water molecules and 8 ions of each kind equivalent to a 2.2 molal solution. The simulation extended over 10 ps with an average temperature of 305 K. The structure is discussed by means of ion-water, ion-ion and water-water radial pair distribution functions and the orientation of the water molecules. Potential energy relationships are reported and the heat of solution has been calculated and found in agreement with experimental values.
The Second Hydration Shell of Li+ in Aqueous LiI from X-Ray and MD Studies
Authors: Radnai T. , Pálinkás G. , Szász Gy I. , Heinzinger K.
Published: February 2015

Indications from a molecular dynamics simulation of a 2.2 molal LiI solution of the existence of a second hydration shell of Li+ have been checked by an x-ray investigation of the same solution. The scattering data are analysed via partial structure functions and radial distribution functions which have been obtained from a model fitted to the total structure function. Experiment and simulation agree on first neighbor ion-water distances. An octahedral arrangement of six water molecules in the first hydration shell of Li+ and additional twelve water molecules in the second shell have been verified by the experiment.
Connection Aspects of the Non-linear Schrödinger Equation
Authors: Grauel A.
Published: February 2015

Some geometrical features of the non-linear Schrödinger equation are studied and it is described how the Schrödinger equation can be obtained from the non-linear scattering equations. The SL(2, ℝ)-evalued elements of the matrix of the non-linear scattering problem are interpreted as matrix-valued forms. We calculate the curvature form with respect to a basis of the Lie algebra. If the curvature form equals zero then we obtain the non-linear Schrödinger equation.
EPR of Gd3+ in a Single Crystal of Thorium disulfide (ThS2)
Authors: Amoretti G. , Giori D. C. , Varacca V.
Published: February 2015

In this paper we report the experimental angular behaviour of the EPR spectra for a single crystal of Thorium disulfide (ThS2) doped with Gd3+ at very low concentration (of the order of 10 p.p.m.). The experimental data are interpreted in terms of a spin Hamiltonian which reflects the crystal field symmetry at the Th site, that is monoclinic Cs, and therefore shows that the doping ions enter substitutionally without lowering the site symmetry. The low symmetry and the unusually large values of the crystal field parameters b2
0 and b2
2 have made it necessary to use a numerical fitting procedure, starting from the exact numerical diagonalization of the energy matrix for any given direction of the static magnetic field.
A Contribution to the Microwave Spectrum of 1,2-Difluoroethane
Authors: Dreizier H. , Steffek D.
Published: February 2015

The microwave spectrum of gauche 1,2-difluoroethane w as investigated in the ground and five vibrationally excited states by a centrifugal distortion analysis.
Proof of Renormalizability and Derivation of Dynamical Equations for Relativistic Composite Particle Systems and Reactions in Unified Field Models
Authors: Stumpf H.
Published: February 2015

In any quantum field theory of matter, in particular in quark-and subquark models, bound states have to be treated. In coupling theories corresponding bound state equations are derived by the Gell-Mann-Low procedure from the Greenfunction hierarchy. Due to certain presupposi-tions neither the derivation of such generalized Bethe-Salpeter equations nor the normalization of their amplitudes are selfconsistent. In this paper bound state equations and general reaction equations for composite particles are derived by means of functional techniques which do not rest on such presuppositions. The derivation is performed for a unified lepton-quark model with boson fusion from fermions, which is described by a nonlinear spinorfield equation with higher order derivatives. Besides the removal of infinities, in coupling theories renormalization mainly means the introduction of dressed field operators which allow a biunique map between field opera-tors and particles. For composite particles renormalization means the dressing of the composite systems which must allow the unique identification of dressed composite particle states independently of the interactions which can take place with other composite systems, i.e. this is in principle the same program as in coupling theories but with the treatment of dressed composite particles instead of dressed field operators. The program is performed for the reaction equations mentioned above.
Properties of a One-Dimensional Coulomb Gas
Authors: Heffernan Daniel M. , Liboff Richard L.
Published: February 2015

The BBKGY equations for N identical, impenetrable, charged particles which move in one dimension and lie in a charge neutralizing background, are shown to separate into N uncoupled equations for the sequence of N reduced distributions. The potential relevant to any subgroup of s adjoining particles is that of an «-dimensional harmonic oscillator whose frequency is the plasma frequency of the aggregate. The «-particle spatial equilibrium distribution reveals that particle vibrations remain centered about fixed, uniformly distributed sites as σ/T goes from zero to infinity, where σ is particle density and T is temperature. Thus it is concluded that the system suffers no change in phase for all σ and T.
Solitary Waves Propagating Along a Magnetic Field in a Warm Collisionless Plasma
Authors: Shivamoggi Bhimsen K.
Published: February 2015

A study is made of solitary waves propagating along a constant, uniform magnetic field in a warm collisionless plasma. The calculation is based on a two-fluid model of the plasma. It is found that the effect of the thermal motion of ions and electrons is to reduce the amplitude but enhance the velocity of propagation of the solitary wave.
A 133Cs-NMR Study of the Chemical Bonding of the Solid Compound Semiconductor Cs3Sb
Authors: Dupree R. , Kirby D. J. , Freyland W.
Published: February 2015

133Cs nuclear magnetic resonance has been studied in the solid compound semiconductor Cs3Sb between room temperature and the melting point. From the magnitude of the chemical shift (620±25 ppm at 300 K) and the quadrupolar coupling constant {e2 qQ/h = 105 ± 3 kHz) we conclude that predominantly ionic bonding does not occur in this semiconductor.
Explicit Liapunov Functions for a Class of Dissipative Systems with Circulatory Forces
Authors: Tasso H.
Published: February 2015

A class of dissipative systems with circulatory forces is given for which a necessary and sufficient condition for stability can be expressed as an explicit Liapunov function equivalent to the Hermitian form of a Hermitian matrix. For a discretized continuous system this matrix has a band structure.
Resonant Excitation of High Amplitude Oscillations and Hydrodynamic Wave Breaking in a Streaming Cold Plasma
Authors: Mulser P. , Takabe H. , Mima K.
Published: February 2015

The excitation of large amplitude electron oscillations in a streaming cold plasma and the minimum threshold of wave breaking in the resonant region are investigated analytically as a function of flow velocity. The problem is reduced to the solution of a driven harmonic oscillator with time varying eigenfrequency ωp(t) in a self-consistent, stationary ion density profile. An analytical solution is presented and applied to the correct wave breaking criterion in a streaming plasma. Wave breaking sets in when the driver amplitude Êd obeys the inequality

which shows that the threshold is proportional to the driver frequency ω and to the flow velocity at the resonance point, vc; however, it is independent of the density scale length. Resonance ends at η = π/2. The denominator assumes there the value 2.759. η is a dimensionless time which measures the transit time of a volume element through resonance.
Molecular Orbital Theory of the Electronic Structure of Organic Compounds IV. A CNDO/S-CI SCF MO Study on the Lower Electronic States of Large Molecules. Singlet-triplet Transitions of Dioxodiazacycloalkanes
Authors: Grinberg Horacio , Marañon Julio , Sorarrain Oscar M.
Published: February 2015

The semiempirical molecular orbital CNDO/S-CI spectral parameterization has been used to elucidate the lower triplet electronic states of a series of dioxodiazacycloalkanes. The 1 3 B2(n0π*) and 1 3 A2 (n0π*) triplet spectroscopic states involve intramolecular charge transfer from the oxygen to the carbon atom of the carbonyl group, which is supported by electron density calculations of these excited states. The solvation energy was incorporated in the calculations.
Condensed Aromatics. Part XV. Chrysene
Authors: Cyvin B. N. , Klaeboe P. , Whitmer J. C. , Cyvin S. J.
Published: February 2015

The in-plane and out-of-plane molecular vibrations of chrysene are analysed. Complete sets of independent symmetry coordinates are constructed. The in-plane vibrational frequencies are calculated both by the simple five-parameter approximation and the method of Califano with collaborators. They show a satisfactory agreement with observed values. Calculated frequencies for the out-of-plane vibrations were obtained from a five-parameter approximation. Mean ampli-tudes of vibration are discussed, and selected values reported. Spectra of chrysene were recorded in Raman and infrared. An almost complete assignment of observed fundamentals was achieved with the aid of the calculated frequencies.
Experimentelle und Quantenchemische Untersuchungen der Dipolmomente von Donator-substituierten 4-Isocyanat-trans- Stilbenen im nichtrelaxierten angeregten Singulettzustand
Authors: Gryczyński I. , Kawski A. , Jung Ch. , Janić I.
Published: February 2015

The electric dipole moments of 4-isocyanate-4′-dimethyl-amino-trans-stilbene(I), 4-isocyanate- 4′-methoxy-trans-stilbene(II) and 4-isocyanate-3′,4′-dimethoxy-trans-stilbene(III) in the relaxationless first excited singlet state (μe) have been determined from the solvent effect and compared with the values calculated with the quantum chemical Parisser-Parr-Pople method.
A Firmly Localized Hole Center in the Mineral Brazilianite NaAl3(PO4)2(OH)4
Authors: Requardt A. , Hill F. , Lehmann G.
Published: February 2015

A hole center on an oxygen adjacent to one aluminum and one phosphorous was detected and analyzed in natural and X-ray irradiated brazilianite. The slightly anisotropic 27 Al shfs splitting is larger than in many other hole centers in which the Al is a lower valency impurity ion with only a coordinative bond to an oxygen lone pair. The hole is trapped at an oxygen with particularly long bond distances to one P and two Al. Thus one structural Al must be substituted by a presumably divalent cation of yet unknown nature. No optical absorption is associated with this center, therefore the large distortion of the coordination polyhedra must be responsible for absence of a light-induced hole transfer between different oxygen ions. Comparison with other systems suggests that the energy differences for other configurations of the hole center are also too high to allow thermal hopping of the hole at or below room temperature. Possible mechanisms for formation and destruction of this center are deduced from experimental results.
A New Formula for the Spectral Line Broadening in Plasmas with Application to the Asymmetry of Ly-α
Authors: Hegerfeldt Gerhard C. , Reibold Reinhard
Published: February 2015

Some time ago, von Waidenfels [4] derived a systematic series expansion of the exact line shape function in case of a single perturber species. In view of the involved mathematics it remained unclear to what physical approximation the first order term of the series corresponds. Here we generalize the approach to two perturber species, one of which is treated quasi-statically (ions), and give a direct physical derivation of the first order term. This term incorporates non-commutativity of ion and electron potentials. In the numerical evaluation for Ly-α it turns out that the noncommutativity effects are washed out to a large extent by the averaging process.
Determination of the Energy Level V0 of Electrons in Liquid Argon over a Range of Densities
Authors: Allen Augustine O. , Schmidt Werner F.
Published: February 2015

The energy level V0 of electrons injected into liquid argon was determined over the range of temperatures and densities in which the electron mobility passes through a maximum. A minimum in V0 was found, not at the density of the mobility maximum as expected, but at a somewhat higher density.
Electrical Conductivity and NMR-Investigations in the A15-and σ-Phase of V-Co Compounds in the High Temperature Range
Authors: Ploumbidis D. , Hüber G.
Published: February 2015

The electrical resistivity of the A15-and σ-phase of V-Co compounds has been measured in the temperature range 300 to 1300 K. Its temperature coefficient is found to be positive for the A15-phase, but negative for the σ-phase. For the same compounds we carried out 55V-and 59Co-Knight shift measurements in the high temperature range (300-1100 K). The 51V-NMR-line corresponding to the central transition (m = +½→m= -½) shows over the entire temperature range the characteristic splitting due to the second-order quadrupole interaction, whereas the 59Co-NMR-line does not show any splitting. Using these NMR measurements we determined for the A15-phase the isotropic and anisotropic parts of the 51V-Knight shift, the quadrupole coupling constant e2qQ/h and the "line width" ⊿B. The experimental results are discussed in the frame of models concerning hyperfine field and electric conductivity of transition metals and their alloys.
Viskositätsabhängigkeit der Fluoreszenzquantenausbeute von Donator-Akzeptor-substituierten trans-Stilbenen in unpolaren wenig viskosen Lösungsmitteln
Authors: Gloyna D. , Kawski A. , Gryczyński I.
Published: February 2015

Fluorescence quantum yields, φf, of donor-acceptor substituted trans-stilbenes, 1, in n-heptane and toluene depend upon the solvent dynamic viscosity η according to the relation ln(φf
-1 - 1) = a ln(η-1)+b. By changing the temperature (278 < T < 343 K) the viscosity was varied. The viscosity dependence of φf can be accounted for by a corresponding viscosity depending radiations less deactivation of the S1 state, which in low solutions is first of all determined by the intramolecular donor-acceptor and universal intermolecular solute-solvent interactions, and then by viscosity.
Kinetics of Acid-Catalysed Hydrolysis of Diethylsuccinate in Dioxane-Water Mixtures
Authors: Khalil Fayez Y . , Abdel-Halim F. M. , Asaad Adel N.
Published: February 2015

The specific rate constants k1 and k2 of the consecutive first-order acid-catalysed hydrolysis steps of diethylsuccinate in dioxane-water mixtures covering the range 0-95% (w/w) of dioxane are determined at 25-55 °C. As the concentration of dioxane increases, the rate of the reaction decreases to a minimum at about 90% (w/w) dioxane, after which it increases again. The ratio k1/k2 was found to be almost constant at the value 2.0. The activation energies of the reaction are independent of solvent composition. Available electrostatic theories regarding the effect of the dielectric constant on the rate are presented, from which the reaction is shown to be an ion-molecular dipole type of interaction. The thermodynamic parameters and the radii of the activated complex at different solvent compositions are calculated and discussed.