bluuebunny/crossref_metadata_2025 huggingface dataset:
How Constant are Fundamental Physical Quantities?
Authors: Eichendorf W. , Reinhardt M.
Published: February 2015

We reinvestigate Dirac's large number hypothesis (LNH) which implies the variation of one or more basic physical constants with time. We show that the ratio of the inertial masses of elementary particles and the fine structure constant a do not vary with time in the LNH.

Using geochemical data on the surface temperature of the earth in the precambrian we can rule out Dirac's conjecture that the gravitational constant G is inversely proportional to cosmic epoch with and without matter creation. Our limit on Ġ/G is one of the best available. We can exclude Gamow's proposal to save the LNH by a variation of the elementary charge e. We also put an upper limit on the variation of the mass of elementary particles.

With the data available at present, we cannot rule out Dirac's LNH if either the mass of elementary particles or the velocity of light and Planck's constant are time dependent. A few other models of variable physical constants are also discussed and excluded.
On Thermalisation of Energetic Charged Particles in Fusion Plasma with Quantum Electrodynamic Considerations
Authors: Ray P. S. , Hora H.
Published: February 2015

The process of energy loss of charged heavy particles in plasma has been discussed taking into consideration photon emissions by electrons of plasma during scattering as is necessitated by quantum electrodynamics. Although the range in general increases with temperature, it is found that the numerical formula of former treatment giving a range as T3/2 is not in general, obeyed. The range is susceptible to the initial energy as well as mass of the heavy particle as can be seen from the cases of alphas and reaction protons for DT, DD(→p + He3) and D He3 plasmas.
Temperature Dependence of the Thermal Resistivity of Noble Metals
Authors: Gupta O. P. , Kharoo H. L. , Hemkar M. P.
Published: February 2015

The temperature dependence of the thermal resistivity of copper, silver, and gold is calculated within the free electron approximation and using the anisotropic continuum dispersive model proposed by Sharma and Joshi for the lattice dynamics of cubic metals. The phonon spectrum has been calculated with the help of the modified Houtson's spherical six-term procedure as elaborated by Betts at al. Bardeen's matrix elements for the scattering of free electrons have been incorporated into the variational expression developed for the Boltzman transport equation. The theoretically calculated resistivity values of copper, silver, and gold are in reasonable agreement with the experimental data.
“Syncope Implies Chaos” in Walking-stick Maps
Authors: Rössler Otto E.
Published: February 2015

A number of 3-variable chemical and other systems capable of showing 'nonperiodic' oscillations are governed by walking-stick shaped maps as Poincare cross-sections in state space. The 2-dimensional simple walking-stick diffeomorphism contains the one-dimensional 'single-humped' Li-Yorke map (known to be chaos producing) as a 'degenerate' special case. To prove that chaos is possible also in strictly 2-dimensional walking-stick maps, it suffices to show that a homoclinic point (and hence an in­ finite number of periodic solutions) is possible in these maps. Such a point occurs in the second iterate at a certain (modest) 'degree of overlap' of the walking-stick map. At a slightly larger degree, a 'nonlinear horseshoe map' is formed in the second iterate. It implies presence of periodic trajectories of all even periodicities (at least) in the walking-stick map. At the same time, two major, formerly disconnected, chaotic subregimes merge into one. Diagnostic criterion: presence of 'syncopes' in an otherwise non-monotone sequence of amplitudes.
Thermoelectric Power of the Molten Systems PbCl2—MeCl (Me = Li, Na, K, Rb, Cs)
Authors: Schiraldi Alberto , Pezzati Elisabetta
Published: February 2015

Initial thermoelectric power determinations where carried out by means of Pb electrodes and Cl2 electrodes thermocells on the molten system PbCl2-MeCl (Me = Li, Na, K, Rb, Cs).

Combinations of the results coming from the two kinds of thermocells allowed to verify Rein-hold's relation and to estimate the partial molar formation and excess entropies of PbCl2.
Ligand-Field Calculations on Pseudo-Tetragonal Ni(II) Compounds
Authors: Vermaas A. , Groeneveld W. L. , Reedijk J.
Published: February 2015

Magnetic susceptibility, magnetic saturation, ligand field and EPR measurements are reported for the compounds Ni(5-methyl pyrazole) 4X2, (X = Cl, Br, I). All data are interpreted using ligand-field calculations, yielding parameters D q, D s, D t, B, C, g∥, g⊥,D, ζ∥, ζ⊥, and k.

All data fit with a single set of parameters. The zero-field splittings and g values are determined from the magnetic measurements, whereas the excited state splittings are determined from the ligand-field spectra.

In studying the relation between the zero-field splitting of the Ni(II) ion and both the spinorbit coupling and spectroscopic energy parameters, a description using an anisotropic spin-orbit coupling gave the most reliable fit.

In addition, known ligand-field spectra and D values of Ni (pyrazole) 4X2, (X = Cl, Br, I) were considered. The derived energy parameters of the corresponding pyrazole and 5-methyl pyrazole compounds are very similar.
Fall-Off Curves for the Reaction ClO + NO2( + N2) ClONO2 (+N2)
Authors: Zellner Reinhard
Published: February 2015

Fall-off curves for the reaction ClO+NO2(+N2)→ClONO2(+N2) at 300 and 220 K have been calculated from Kassel integrals by use of a theoretically derived high pressure limit and the experimentally determined low pressure limit as reference points. The reaction is found to deviate considerably from the low pressure limit at pressures larger than 10 Torr. Effective rate constants for the use in atmospheric models of chlorine nitrate formation are derived.
Stationary States of the Classically Radiating Electron in an Attractive Potential
Authors: Sorg M.
Published: February 2015

It is shown by explicit numerical calculations, that the recently proposed non-local equations of motion, which can be supplied by a modified form of the well-known Caldirola equation, all admit the possibility of stationary radiationless motions in an attractive potential.
Radiative Recombination Coefficients in Plasmas of Low Density
Authors: Mital H. P. , Chandra Suresh , Narain Udit
Published: February 2015

Radiative recombination coefficients for Ne, A, Kr, Xe, N, and 0 in plasmas of low density are calculated in the temperature range 10-104 K.
Effect of Tl Concentration on the Thermoluminescence of Deformed NaCl:Tl Phosphors
Authors: Joshi R. V. , Joshi T. R.
Published: February 2015

It is known that thermal and/or mechanical pretreatment influences the luminescent behaviour of phosphors. It has been reported that mechanically pretreated NaCl : Tl specimens, exposed to ultraviolet radiation, exhibit a pronounced glow peak at 420 K. The present work concerns the study of the intensity of this peak as a function of impurity concentration. There is a remarkable growth in the intensity of the 420 K glow peak with decreasing concentration. This can be explained on the basis of the interaction between impurity ions and moving dislocations.
EPR of Mn2+ in Pr2Mg3(NO3)12 · 24H2O Single Crystals
Authors: Jain V. K. , Srinivasan T. M.
Published: February 2015

EPR of Mn2+ in Pr2Mg3(NO3)12·24H2O single crystals has been studied at X-band. Mn2+ substitutes two inequivalent Mg2+ sites. The spin-Hamiltonian analysis of the EPR spectra is presented at 298 K as well as 77 K.
Sextische Zentrifugalverzerrungskonstanten und Mikrowellen-spektren bis 130 GHz von 12C32SF35Cl
Authors: Hamm R. , Günther H. , Zeil W.
Published: February 2015

It has been demonstrated that Watson's energy formula for the centrifugal distorted rotor is no longer sufficient for highly excited states. For the CSFCl molecule, the formula can only be used up to a limit of about J = 30. Beyond this rotational quantumnumber Watson's sextic Rotational Hamiltonian should be used for fitting the rotational energy parameters. Good results were obtained up to J = 70 using the sextic Hamiltonian and diagonalizing numerically the energy matrix set up in the rigid symmetric rotor basis. The sextic centrifugal distortion constants could be determined to a sufficient degree of exactness, i. e. the absolute value of the constants is considerably greater than the errors.
Microwave Spectrum and Barrier to Internal RotationinCH3COC15N
Authors: Pandey G. K. , Dreizler H.
Published: February 2015

The ground state rotational spectra of the 15N isotopic species of acetyl cyanide have been measured in the region from 8 to 40 GHz. The rotational and centrifugal distortion constants have been determined by a least squares fit to about 38 transition frequencies with J ≦ 14. The potential barrier parameter V3 and the angle a between the top axis and the 'a-axis' have been determined by a least squares of the (A-E) splittings of about 27 transitions. The methyl top moment of inertia was fixed at 3.14 amu Å2
The Field Within a Commercial EI/FI Source of a Mass Spectrometer
Authors: Feys J. P. R. , Mey G. De , Claeys E. G. , Kelen G. P. Van der
Published: February 2015

A novel method for the calculation of the potential distribution in a mass spectrometer source is presented. It consists in solving a Green integral equation and applies both to the FI and EI mode of a CEC 21-110 C mass spectrometer source.
A Study of the Electronic Spectrum of 3,4-Benzphenanthrene Cation Radical
Authors: Khan Zahid H. , Khanna B. N.
Published: February 2015

The electronic spectrum of 3,4-benzphenanthrene cation radical is studied for the first time experimentally as well as theoretically. The cation radicals have been produced in boric acid glass by photooxidation and the absorption spectrum is measured in the region 200-1400 nm. An interpretation of the spectrum is given on the basis of Pariser- Parr (PP) and Free Electron (FE) molecular orbital calculations using limited configuration interaction. It is found that the results based on the PP method are in better agreement with experiment as compared to the FE method. Furthermore, the spectral shifts and other variations observed between the spectra of the cation and anion radicals are attributed to the characteristics of these species.
Der Einfluß des Phonon -Mitzieheffektes auf die thermoelektrischen Koeffizienten in Metallen / Influence of Phonon Drag on the Thermoelectric Coefficients in Metals
Authors: Roloff D. , Simon G.
Published: February 2015

The system of coupled Boltzmann transport equations for electrons and phonons in a metal is considered in the absence of a magnetic field. Usually these equations are decoupled by “Bloch′s assumption”, that is the phonon gas is considered to stay in equilibrium with respect to the trans­ port equation for the electrons.

It is shown that the coupled system of equations has finite solutions only if some other relaxation process than the electron-phonon interaction is present, for instance the phonon-phonon-interaction. With some simplifying assumptions the full system of equations is solved for high temperatures. The contributions of the phonon-drag to the thermoelectric transport coefficients are derived and discussed.
A Dielectric Instability of a Fermion Gas in a Random Potential
Authors: Dallacasa V.
Published: February 2015

A dielectric instability of a collection of charged fermions interacting via Coulomb forces and subjected to a random external field is pointed out. It is shown that, as a result of localization produced by the random potential, an RPA Coulomb field can generate a dielectric instability, both static or frequency dependent, resulting in a static or oscillating crystalline arrangement of the fermions. In simple metals, such as the alkali metals, this mechanism is shown to provide an explanation of the existence of the crystal lattice and of acoustic phonons.
On the Influence of Intra - and Inter-Molecular Hydrogen Bonding on the Excited State Lifetime of Indigo Dyes
Authors: Windhager W. , Schneider S. , Dörr F.
Published: February 2015

It is shown that intramolecular hydrogen bonding can give rise to very fast nonradiative desactivation of the S1 -state of indigo dyes. In those derivatives, which lack the possibility of internal hydrogen bonds, hydrogen bonding to suitable solvent molecules can provide the channel for fast radiationless transitions. As a consequence, drastic effects on the S1 -state lifetime are observed both as a function of solvent and/or temperature.
Proton Magnetic Resonance and Molecular Motion in Solid Methyl-Piperidines and Piperazines
Authors: Schüler R. , Brücher L. , Müller-Warmuth W.
Published: February 2015

The 1H-NMR spin-lattice relaxation time and lineshape in solid 2-, 3-, and 4-methyl-piperidine, in 2-and N-methyl-piperazine, and in NN′-diinethyl-piperazine has been measured from low temperatures to the melting point. For all cases, the experimental data can be described by classical rotation of the methyl group. Activation energies governing this motion are between 9 and 14 kJ/mole. Second moments are reduced from about 25 G2 to 17 G2. No further line-narrowing was observed.
Rotational Spectrum , Electric Dipole Moment, Quadrupole Coupling , and Partial r0- Structure of 3 -Cyanothiophene
Authors: Wiese J. , Sutter D. H.
Published: February 2015

The microwave rotational spectrum of the most abundant species of 3-Cyanothiophene was investigated for the ground vibrational state. Rotational constants and centrifugal distortion constants are given. The electric dipole moment components μa and μb and the 14N-quadrupole coupling constant X + = X bb + X cc were determined from the Stark-effect splittings and hfs-splittings respectively. The experimental results are compared to CNDO/2 calculations and are discussed with reference to ring distortion.
Notizen: The Dipole Moment Function of HF Molecule Using Morse Potential
Authors: Chan Y. K. , Rao B. S.
Published: February 2015

The radial Schrödinger wave equation with Morse potential function is solved for HF molecule. The resulting vibration-rotation eigenfunctions are then used to compute the matrix elements of (r - re)n. These are combined with the experimental values of the electric dipole matrix elements to calculate the dipole moment coefficients, M 1 and M 2.
Heat Transfer Through a Gas Between Parallel Plates
Authors: Waldmann L.
Published: February 2015

Within the framework of boundary conditions recently developed for the linearized Boltzmann equation 1 the problem of heat transfer between parallel plates can be solved in terms of "transport- relaxation eigenfunctions". The particle distribution function and the total heat transfer in the Knudsen case are exactly expressed by integrals over the interfacial scattering kernel occurring in the new scheme. A detailed discussion of the general case gives an exact formula and sign statement for the temperature jump at parallel plates. An approximation, which encompasses v. Smoluchowski's approach, lies at hand. This approximation is also readily confirmed by a moment method.
Attenuation and Velocity of Ultrasonic Waves in Amorphous Selenium in the Vicinity of the Glass Transition
Authors: Kittinger Erwin
Published: February 2015

Attenuation and velocity of longitudinal ultrasonic waves have been measured in a-Se in the vicinity of the glass transition. Both quantities are shown to be affected significantly by the stabilization process below the glass transition temperature Tg. Equilibrium values of sound velocity are also reported for the range 25 °C to 45 °C. The decrease (increase) of attenuation (velocity) during stabilization is reversed at higher temperatures. The connection of both quantities is discussed in terms of an effective temperature which allows the approximate determination of equilibrium values of attenuation (and possibly of other structure related properties) from measurements performed in nonequilibrium states.
Identification of Thermoluminescence Traps in CaWO4 and BaWO4 by EPR Measurements
Authors: Hofstaetter A. , Planz J. , Scharmann A.
Published: February 2015

In calcium-and barium tungstate crystals both containing molybdenum and phosphorus, para­magnetic centres are created by X-ray irradiation at room temperature. Two kinds of centres are identified by EPR measurements; an electron trapped at a molybdate complex and a hole trapped at a phosphate complex. The EPR parameters of the hole centres are temperature dependent indicating motional effects. A connection of these two traps with the observed thermoluminescence is found for both crystals.
207Pb Magnetic Shielding Anisotropy in Pb(NO3)2, PbCO3, PbCrO4, PbMo04 and PbWO4 by Fourier Transform NMR
Authors: Nolle A.
Published: February 2015

The NMR signals of 207Pb have been observed in powder samples of Pb (NO3)2, PbCO3 , PbCrO4 , PbMoO4 and PbWO4 using a Fourier transform apparatus. All the observed signals are asymmetrical, indicating anisotropics of the magnetic shielding σ33- σ11 with values between - 56ppm for Pb(NO3)2 and - 884 ppm for PbCrO4 . The principal elements of the shielding ten­ sors σ11 , σ22 , σ33 are given relative to the Pb2+ ion at infinite dilution in H2O and can be referred to the free lead atom with the known shielding constant of earlier measurements.
Die Bildung negativer Ionen bei Elektronenstoß auf WF6 / Formation of Negative Ions from Electron Impact on WF6
Authors: Wall R. de , Neuert H.
Published: February 2015

The formation of negative ions from WF6 by bombardment with electrons has been studied using a conventional mass spectrometer with an electron impact ion source. At higher electron energies WF6
--, WF5
--, WF4
--, WF3
--, and F-- ions have been found. Appearance potentials of WF6
--, WF5
--, WF4
--, and F- resulting from dissociative attachment processes are given. WF4
- and WF2
- have been observed from the decay of a higher excited WF6
- at about 70 eV energy. The electron affinity of WF5 has been derived as 1.25±0.2 eV; the values of D(WF4-F)≦5.5±0.2 eV and E A(WF4) =2.6 eV are suggested.
Solar Energy-Assisted Electrochemical Splitting of Water. Some Energetical, Kinetical and Catalytical Considerations Verified on MoS2 Layer Crystal Surfaces
Authors: Tributsch H.
Published: February 2015

Kinetical, energetical and solid state considerations were elaborated in a search for suitable electrodes for the oxidation of water with visible light. They led to layer type transition metal dichalcogenides and to the photo-electrochemical utilization of optical d-d-transition which do not break chemical bonds. MoS2 was selected as a promising compound and it was actually shown to react with water on illumination with light between 400 and 715 nm. At low electrode potentials the liberation of small quantities of molecular oxygen was traced with polarographic techniques. The main portion of the oxidation products of water was, however, found to be lost for the oxydation of crystal bound sulfur to sulfate. An improvement of this situation in favour of an increased rate of oxygen evolution has been accomplished by means of a redox-catalyst, tris (2,2'-bipyridine) -ruthenium (II), which is oxidized through photochemically generated holes from the MoS2 4 dz²­­- valence band and channels them into oxygen-evolution through nucleo-philic addition of hydroxide. A molecular mechanism was elaborated for the photoelectrochemical oxidation of water on MoS2 and its conclusions tested by investigating the oxidative behaviour of various additional layer-type transition metal compounds. It involves a hole mediated valence change of molybdenum with an intermediate formation of a 5-valent molybdenum hydroxide. A basic kinetical and energetical similarity is suggested with the function of manganese reaction centers in photosynthesis.
Numerical Calculations on Reflection Processes of Ionizing Shocks on the End Wall of a Shock Tube
Authors: Takano Yasunari , Akamatsu Teruaki
Published: February 2015

Numerical calculations have been made about shock reflection processes in ionizing argon on the end wall of a shock: tube. The two-step Lax-Wendroff scheme was employed to solve time-dependent one-dimensional inviscid flow problems for ionizing gases. Complicated flowfields were found to occur due to interactions between ionization relaxation processes and reflected shocks. Calculations were performed for three cases: incident-shock Mach number M s = 16 and initial pressure p1 = 1 torr; Ms = 14 and p1 = 3 torr; M s = 12 and p1 = 5 torr.
Interdiffusion Studies in Liquid Bismuth-Antimony Alloys
Authors: Lamparter Peter , Steeb Siegfried
Published: February 2015

The composition dependence of the interdiffusion coefficient in Bi-Sb melts has been measured in the temperature range from 656 °C to 1010 °C by use of the long-capillary method and electron piobe microanalysis. The measured data can be represented as a function of the temperature by an Arrhenius law: D=D0 exp (-Q/R T).

The concentration dependence of the parameters D0 and Q is given. Analysis of the variation of Q with composition leads to the conclusion that Bi-Sb alloys show more metallic behaviour than unalloyed Bi or unalloyed Sb.

This result is in agreement with the structure of the Bi-Sb melts.
A Topological Formula for Total π-Electron Energy
Authors: Gutman Ivan
Published: February 2015

Total π-electron energy E is presented as a sum of first-neighbour interaction terms λ and contributions of cycles ζ [Equation (2)]. The main conclusion of the work is that the total effect of λ's is a constant, independent of the molecular structure. Therefore, E is an additive function of ζ′s only.
Transport Coefficients of Expanded Fluid Metals
Authors: Tippelskirch H. von
Published: February 2015

The viscosities and the self-diffusion coefficients of expanded fluid mercury and caesium have been calculated as a function of pressure and temperature up to their critical points with the aid of a modified Enskog theory. The results are compared with the transport coefficients of other liquid metals and of non-polar and polar fluids applying the principle of corresponding states. The thermal conductivities of fluid metals along the full coexistence line are also discussed. A classification of the transport phenomena in fluids with various types of interaction forces - including expanded fluid metals - is given
Eigenvalue Spectrum of the Radiation Field in the Flat Parallelepiped
Authors: Eckhardt W.
Published: February 2015

The eigenvalue spectrum of the ideal photon gas in the flat parallelepiped is discussed. For low frequencies the spectrum is that of the two dimensional isotropic space and tends with increasing ω to the spectrum of the 3-dimensional isotropic space
Effect of Non-resonant Impurity Atom Substitution on the 35Cl NQR Spectrum of HgCl2
Authors: Bahadur D.
Published: February 2015

Doping of HgCl2 with small amounts of HgBr2 or Hgl2 affects the 35Cl NQR line intensity very markedly, the effect being greater with the latter impurity. The large magnitude of these impurity effects probably arises from substitution of the 35Cl atom by the non-resonant Br or I atom
Hydrogen Stark Broadening by Model Electronic Microfields
Authors: Seidel Joachim
Published: February 2015

The Method of Model Microfields proposed by Brissaud and Frisch is applied to calculate Stark broadened profiles of hydrogen lines in the static ion approximation. Numerical results for L-α, H-α, and H-β are found to be in good agreement with those derived from the unified theory by Vidal, Cooper, and Smith over a wide range of plasma densities and temperatures. This demon­ strates that reliable line profiles may be obtained from the microfield distribution and covariance alone, more complicated statistical features being less important in this context.
On an Almost Complex Manifold Approach to Elementary Particles
Authors: Ławrynowicz Julian , Wojtczak Leszek
Published: February 2015

An almost complex manifold description of elementary particles is proposed which links the approaches given independently by J. Ławrynowicz and L. Wojtczak, and by C. von Westenholz. This description leads to relations between the curvature form of an almost complex manifold, which accounts for the symmetry classification schemes within the frame of principal fibre bundles, and a curved Minkowski space-time via induced smooth mappings characterizing nuclear reactions of type N+π⇄N, where N is some nucleon and π the virtual π-meson of this reaction. Both approaches follow the same main idea of D. A. Wheeler developed in a different way by A.D. Sakharov.
Multilevel Models of Krypton for the Application to Stepwise Ionization Relaxation Processes
Authors: Bergmann L. , Demmig F.
Published: February 2015

A four step model and two five step models of krypton are developed for application to stepwise ionization relaxation. The four step model is preferred out of practical and economical grounds. The corresponding rate equations for collisional excitation and ionization are given assuming ladder climbing for the electrons. Selected results of an application of the model to ionization relaxation in shock waves are reported.
Optische Hochdruckzelle mit variabler Schichtlänge für quantitative Absorptionsmessungen bis 2,5 kbar und 250°C / An Optical High Pressure Cell with a variable layer Thickness for Quantitative Absorption Measurements to 2.5 kbar and 250 °C
Authors: Buback M.
Published: February 2015

An optical high pressure cell for operation to 2.5 kbar and 250 °C has been developed enabling quantitative absorption intensities to be measured with high accuracy even on strongly absorbing fluids. Moreover, due to the capability of varying the layer thickness under high pressure and temperature substances within a wide concentration range or bands with large differences in molar absorptivity can be determined during one experimental run. The procedure is illustrated by infrared and near infrared spectra measured on pure ethylene.
Microwave Spectrum of Mono-deuterated Acetyl Cyanide CH2DCOCN and Complete rs- and r0-structure of Acetyl Cyanide
Authors: Pandey G. K. , Andolfatto M. , Dreizler H.
Published: February 2015

Microwave spectra of symmetric and asymmetric forms of monodeuterated acetyl cyanide CH2DCOCN have been observed and measured. Significant differences occur between our assign­ment and those of Krisher and Wilson1. We have confirmed all our assignments with the help of microwave - microwave double resonance (MW-MW-DR) experiments. By fitting about twelve low J transition frequencies to a rigid rotator, accurate values for the rotational constants have been obtained. From the analysis of the quadrupole hyperfine splittings of some of the tran­sitions, the nuclear quadrupole coupling constants are also determined.

Using the measured rotational constants for a number of molecular isotopic species of Refer­ence (1), and in addition those measured in this laboratory for the 15N, monodeuterated and normal species (determined with greater accuracy), a complete rs-and ro-structure has been calculated. The important conclusions are - i) the methyl group does not possess C3V symmetry and ii) the Ccarbonyl, - Ccyanide and C - N bonds are collinear within the accuracy of measurements.
Eine Studie zu Abbildungseigenschaften von Hiickel-Parametern / A Study on Mapping Properties of Hückel Parameters
Authors: Brüggemann R. , Voitländer J.
Published: February 2015

A new method to study Hückel parameters is suggested, wherein the essential point is the number of solutions of a system of nonlinear equations.
Elektronenanregungsenergieübergang zwischen gleichartigen Molekülen in Lösung / Electronic Excitation Energy Transfer among like Molecules in Solution
Authors: Kamiński J. , Kawski A.
Published: February 2015

Electronic Excitation Energy Transfer among like Molecules in Solution A theory of the excitation energy transfer among like (bomotransfer) molecules in solution, based on a shell model of the luminescent centre and on the assumptions given in our previous paper * is elaborated. Expressions for the time-dependent concentration depolarisation of the photo-luminescence (for emission anisotropy) in the sphere-and the shell-model are obtained. The expression for the concentration-dependent depolarisation is compared with the experimental results for five luminescent compounds in rigid cellulose acetate films. Good agreement was found with the equation which takes into account the excitation energy remigration.
Nonequilibrium Properties of Weak Ion Exchange Membranes
Authors: Stormberg H.-P.
Published: February 2015

The behaviour of a membrane with a low concentration of fixed charges in a constant external electric field is considered. The stationary flows, the concentration curves and the electric field are calculated for a system which has different concentrations on both sides of the membrane. The starting point of the calculation are the generalized Nernst-Planck equations which are deduced microscopically. Using a perturbation approach a solution to these equations is given. With this result the influence of fixed charges, of friction between the ions and the membrane and of the difference in concentrations can be discussed.
Invariant Distributions and Stationary Correlation Functions of One-Dimensional Discrete Processes
Authors: Grossmann S. , Thomae S.
Published: February 2015

The connection between one-dimensional dynamical laws generating discrete processes and their invariant densities as well as their stationary correlaton functions is discussed. In particular the changes occuring under a special equivalence transformation are considered. Correlation functions are used to describe the gradual transition from periodic states to chaotic states via periodic motions with superimposed nonlinearity noise.
EPR of Mn2+ in Tutton Salts
Authors: Jain V. K.
Published: February 2015

Electron paramagnetic resonance of divalent Mn2+ ions in the Tutton salts M″M2′ (SO4)2·6 H2O, (M′ =Mg, Fe, Zn, Cd and M′ = Rb, Cs) and CdM2′(SO4)2·6 H2O, (M′ = K, NH4) single crystals has been studied at 298 K. The Mn2+ is found to substitute divalent cation sites. The spectra have been analysed using the spin-Hamiltonian appropriate for rhombic symmetry.
R Realisierung rauscharmer 441,6 nm He-Cd-Laser durch Modulation des Entladungsstromes / Realization of low Noise 441,6 nm He-Cd-Lasers by Modulation of the Discharge Current
Authors: Hsieh Tai-chiung , Knauer Wolfgang , Penning Uwe
Published: February 2015

Realization of low Noise 441,6 nm He-Cd-Lasers by Modulation of the Discharge Current A simple method to stabilize the laser light of a 441,6 nm He-Cd-laser at maximum output power is presented. Experiments show that a strong reduction of the fluctuations in the laser output can be achieved by a modulation of the discharge current at specific frequencies in the 100 kHz-range. This also leads to an increase in output power by 10-25 per cent as compared to the unmodulated laser.
On the Association of Phenol and 4-Chlorophenol with N.N-Dimethylmethanesulfonamide
Authors: Pikkarainen L. , Virtanen P.O.I.
Published: February 2015

The association of N,N-dimethylmethanesulfonamide with phenol and 4-chlorophenol was studied by PMR spectrometry at 35 °C in carbon tetrachloride solution. The data are in accordance with a model which includes, in addition to 1:1 complexes, complexes of two phenol and one N,N-dimethylmethanesulfonamide molecule.
The Raman Scattering Spectra and Molecular Conformations of Cetyltrimethyl- ammonium Bromide in Aqueous Solutions
Authors: Okabayashi Hirofumi
Published: February 2015

Laser Raman spectra of aqueous cetyltrimethylammo-nium bromide (CTAB) solutions were measured in the region of 1000-1150cm-1. The relative intensities (I1085/I1128 and I1085/I1067) of skeletal optical modes are ploted against the concentration. Both relative intensities are found to decrease with increasing the concentration. This intensity change is marked around the second CMC. This observation shows that the all-trans chain segments of the CTAB molecules increase with the sphere-rod transition.
Light-Particle-Accompanied Fission and the Three-Center Shell-Model
Authors: Hahn Josef , Lustig Hans-Jürgen , Greiner Walter
Published: February 2015

Light-particle accompanied fission is expected to yield results from which one hopes to learn more about binary scission configurations. As a step in this direction, we present a model that allows the calculation of the probabilities with which a given three-particle setup follows from different binary configurations. First results show the workability of the model.
A Relativistic Model for Isobar Configurations in the Two-Nucleon System
Authors: Arenhövel H.
Published: February 2015

A relativistic description of isobar configurations in the two-nucleon system is obtained by phe-nomenologically extending the Bethe-Salpeter-equation to channels comprising configurations of internally excited nucleons. The generalized equation is then reduced by standard methods to a three-dimensional relativistic equation. Various possible off-mass-shell extrapolations involved in this reduction are discussed. The best choice seems to be where the relative energy of the two particles is fixed to zero. Then all diagonal and transition OBE-interactions do not contain any retardation and have the normal Yukawa range.
Variations in Nuclear Decay Rates
Authors: Dostal K.-P. , Nagel M. , Pabst D.
Published: February 2015

This paper is intended to provide a concise introductory review of the fundamental principles underlying the higher-order effects of nuclear decay rate variations which may be produced by physical or chemical means. The first part of the paper embraces the theoretical foundations of the subject matter, and the second deals with methodological and experimental questions. Several tables summarize published experimental results and the pertinent literature.
13C NMR Spectra of Trimethylene Oxide and Sulphide
Authors: Jokisaari Jukka , Kuonanoja Juha , Häkkinen Anna-Maija
Published: February 2015

The 13C NMR spectra of trimethylene oxide and trimethylene sulphide have been recorded and analysed as second-order spectra. The values of all the C-H coupling constants with their signs are reported. The signs of the C-H coupling constants in trimethylene oxide were determined by selective irradiation experiments and theoretical calculations, while in trimethylene sulphide the signs were obtained directly from the analysis. The one-bond C-H coupling constants are approximately 3 Hz greater in trimethylene oxide than in trimethylene sulphide, while the absolute values of the two-bond and three-bond coupling constants, 2JCᵦH and 3JCαH, are about 1 Hz greater in the latter molecule.
Molecular g-Values, Magnetic Susceptibility Anisotropics, Second Moments of the Charge Distribution, and Molecular Electric Quadrupole Moments in trans- and cis-Thioformic Acid
Authors: Pandey G. K. , Sutter D. H.
Published: February 2015

The rotational Zeeman effect in the microwave spectrum of trans- and cis-Thioformic Acid has been investigated at field strengths upto 25.6 kG. Measurements were done for both ⊿M = 0 and ⊿M = ± 1 selection rules for the trans species and for ⊿M = ±1 for the cis species. From the observed splittings the following parameters were obtained for the diagonal elements of the molecular g tensor and the susceptibility anisotropics.

(all experimental uncertinties are single standard deviations).

The molecular electric quadrupole moments derived from the Zeeman data indicate that there is no significant covalent bonding in the O…H region of the trans species.
LCAO MO Investigations on Lignin Model Compounds VI. CNDO/CI Calculations of Electronic Spectra of Cinnamaldehyde Structures
Authors: Remko Milan , Polčin Jan
Published: February 2015

The electronic absorption spectra of cinnamaldehyde, o-, m-, p-hydroxycinnamaldehyde and 3-methoxy-4-hydroxy cinnamaldehyde were theoretically and experimentally studied, by means of the semiempirical CNDO/CI method. The calculated and observed transition energies were in good agreement.
35Cl and 37Cl Pure Quadrupole Resonance in α-CH2ClCOOH: Hydrogen Bonding and Chlorine Isotope Effect
Authors: Rager Helmut
Published: February 2015

The temperature dependence of the pure nuclear quadrupole resonance of 35Cl and 37Cl in solid α-CH2ClCOOH has been measured from 77 K to 298 K. The NQR spectrum consists of a doublet arising from the two nonequivalent chlorine atoms in the unit cell. The temperature dependence was calculated using the Bayer-Kushida theory which gives a satisfactory fit to the NQR spectra in the temperature range investigated. From the NQR data evidence of an isotope effect was found for both nonequivalent chlorine atoms. The isotope effect depends on the C-Cl bond length and its direction probably on the state of binding of the chlorine atoms. The NQR results and their interpretation are consistent with the crystal structure of α- CH2ClCOOH.
Influence of Aggregation on the Fluorescence Decay of Organic Laser Dyes
Authors: Knof J. , Theiss F.-J. , Weber J.
Published: February 2015

Singlet decay times in dependence on temperature, concentration, solvent and detergent were measured in solutions of organic laser dyes. In the temperature range from 300 K to 115 K the reciprocal decay time obeys an Arrhenius relationship, the parameters of which were determined. Additional measurements were carried out on Acridinorange because a biexponential fluorescence decay due to monomers (τ = 4.2 ns) and aggregated molecules (τ = 14.7 ns) was found.
Non-LTE Line Transfer with Diffusion of Excited Atoms II
Authors: Düchs D. F. , Rehker S. , Oxenius J.
Published: February 2015

Non-LTE radiative transfer in a spectral line due to two-level atoms is studied taking the diffusion of excited atoms into account. Numerical results are presented for the case of a stationary, plane parallel plasma of constant total density and temperature without external radiation and without exchange of matter with the surroundings, assuming pure Doppler broadening of the spectral line.
The Microwave Spectrum of Oxazole I. The Complete Structure by DRM Microwave Spectroscopy
Authors: Kumar Anil , Sheridan John , Stiefvater Otto L.
Published: February 2015

Double resonance modulation (DRM) microwave spectroscopy has been used to determine the complete substitution structure of oxazole. Isotopic species spectra associated with 13C, 15N and 18O were studied in their natural abundances, while the mono-deuterated species were examined in a mixture of slightly enriched forms.

With uncertainties below 0.002 Å and 0.1° for distances and angles, respectively, the structure parameters of oxazole are as follows:

0(1)-C(2) = 1.3574 Å C(5)0(1)C(2) = 103.91°

C(2)-N(3) = 1.2915 Å O(1)C(2)N(3) = 114.99°

N(3)-C(4) = 1.3954 Å C(2)N(3)C(4) = 103.92°

C(4)-C(5) = 1.3525 Å N(3)C(4)C(5) = 109.04°

C(5)-O(1) = 1.3696 Å C(4)C(5)0(1) = 1O8.I4°

C(2)-H(2) = 1.0750 Å O(1)C(2)H(2) = 117.09°

C(4)-H(4) = 1.0751 Å N(3)C(4)H(4) = 121.89°

C(5)-H(5) = 1.0732 Å O(1)C(5)H(5) = 116.86°

The geometry of oxazole is compared with that of isoxazole and with the structures of the closely related compounds furan and 1,3,4-oxadiazole.
The Microwave Spectrum of Oxazole The DRM-Spectrum of the 15N-Species in its Natural Abundance
Authors: Stiefvater Otto L.
Published: February 2015

In view of a discrepancy between the rotational constants of the 15N-species of oxazole reported in an earlier study on a pure 15N-sample and those found in a recent study on a sample containing the 15N-species only in its natural abundance, the experimental results of the latter study are reported in detail, and they are compared with predictions based on the results of the earlier work.
Investigation of Collision Induced Transitions in the Microwave Range: Ethylene Oxide and Carbonylsulfide
Authors: Dreizler H. , Schrepp W.
Published: February 2015

Collisional energy transfer between rotational levels of ethylene oxide C2H4O, its deuterated species C2D4O and carbonyl sulfide OCS, has been investigated by means of microwave-microwave four-level double resonance. The results are in agreement with collisional selection rules which can be predicted in the weak collision limit. Collisionally induced transitions up to ΔJ = 4 have been detected for C2D4O.
Rotation-Torsion-Vibration Interaction in Acetyl Cyanide: Normal and 15N Isotopic Species
Authors: Pandey G. K. , Dreizler H.
Published: February 2015

The rotation - torsion - vibration interaction in the normal and 15N isotopic species of Acetyl Cyanide is studied in the rotational spectrum of ground, first excited state of methyl torsion and first excited state of CCN in plane bending vibration. With respect to a previous -work [1] a more detailed check of a model with five degrees of freedom, comprising three for the overall rotation and two for the two lowest vibrations was possible.

Potential parameters were fitted simultaneously to the splittings of the rotational transitions in the ground, excited torsional and excited vibrational states for the normal and 15N isotopic species of the molecule. The coefficients V3 and V6 of the Fourier expansion of the hindering potential for the torsion and two interaction constants V3c′ and F3c″ for the torsion and in plane CCN bending vibration were determined, apart from the harmonic force constant k2q for the vibration, which is obtained from the measured infrared data of the normal species. Using these results, the (E-A) splittings of the rotational transitions could be nicely reproduced but not the absolute frequencies of the rotational transitions.
The Molecular Geometry of Trichloromethyl Sulphonyl Chloride as Studied by Electron Diffraction. Estimation of the Barrier to Internal Rotation
Authors: Brunvoll Jon , Hargittai István , Seip Ragnhild
Published: February 2015

The molecular geometry of trichloromethyl sulphonyl chloride has been determined by electron diffraction. The sulphur bond configuration [rg(S=0) 1.421±0.003 Å, rg(S-Cl) 2.021 ±0.005 Å, rg(S-C) 1.87±0.03 Å, ∠O=S-C 108.3±0.7°, ∠C-S-Cl97.9±0.8°, ∠O=S=O 121.5±0.9° and ∠O=S-Cl 109.2±0.6°] is consistent with the characteristic structural variations observed in the sulphone series. The barrier to internal rotation around the S-C bond was estimated to be between 3.5 and 6 kcal mol-1 by means of various procedures and assumptions.
Intramolecular Rotation in Some Trihalogenated Esters at Microwave Frequencies
Authors: Purohit H. D. , Vyas A. D. , Lunker H. C.
Published: February 2015

The permittivity and dielectric loss of methyl, ethyl and n-propyl trichloroacetate in decalin solution have been measured at four microwave frequencies viz., 30.20, 24.50, 18.26 and 9.83 GHz and also at 1 MHz and optical frequency at 35 °C. The permittivity and dielectric loss at different frequencies have been plotted against concentration (wt. fraction). The slopes of these straight lines have been used for complex plane plots (a″ vs a′). The dispersion curves which could not be resolved in benzene could be resolved in decalin due to the increase in viscosity of the solvent. Data have been analysed in terms of two relaxation processes i.e., overall rotation and group rotation.
Ferromagnetism in Some Semi-Conducting Heavy Rare-Earth Molybdates
Authors: Lai H. B. , Pandey R. N.
Published: February 2015

Measurements of the magnetic susceptibility of powdered samples of Dy2(MoO4)3, HO2(MoO4)3 and Er2(MoO4)3 in the temperature range 300 to 920 K are reported. The Curie Weiss Law is obeyed and yields the magneton numbers 10.72, 10.68 and 9.68 for the Dy3+, Ho3+ and Er3+ ions, respectively, the theoretical values being 10.63, 10.60 and 9.60. The results are analysed in terms of molecular field theory and it is predicted that Dy2(MoO4)3, Ho2(MoO4)3 and Er2(MoO4)3 become ferromagnetic below 12, 17 and 5 K, respectively.
Photoelectron Spectroscopy of Heterocycles. Polypyridines
Authors: Novak I. , Klasinc L.
Published: February 2015

The photoelectron (PE) spectra of 2,2′-bipyridine 1, 2,2′:6′,2″-terpyridine 2, and 2,2′,2″,2‴-tetrapyridine 3 have been measured using He I radiation. For 1-3 standard SCF LCAO MO calculations wer also performed. Comparison of PE spectra and these calculations allowed the assignment of π-ionizations and indirectly also the nitrogen lone pair ionizations in 1-3. Factors influencing the conformations of 1-3 in the gas phase are also mentioned.
Energy Principle for Dissipative Two-fluid Plasmas
Authors: Tasso H.
Published: February 2015

An energy principle for the dissipative two-fluid theory in Lagrangian form is given. It represents a necessary and sufficient condition for stability allowing the use of test functions. It is exact for two-dimensional disturbances but is still correct in terms of perturbation theory for long wavelengths along the magnetic field. This may well find application in tokamak plasmas. A discussion of the general case and its relation to the stability of flows in hydrodynamics is given. This energy principle may be applied for estimating the magnitude of residual tearing modes in tokamaks.
On the Fine Structure in the Infrared Spectra of Clear Natural Quartz, Amethyst, Citrine and Synthetic Quartz Crystals in the 3400 cm-1 Region
Authors: Chakraborty Dipak , Lehmann Gerhard
Published: February 2015

The fractional intensities of different infrared vibration bands due to hydrogen impurities have been studied in clear natural quartz, amethyst, citrine and synthetic quartz. Integral absorptions of the different bands were found to increase linearly with total hydrogen concentration. The differences in intensity ratios for some prominent bands are distinctive for the type of quartz in some cases. The ratios of isotropic to anisotropic absorption from hydrogen impurities were found to increase with total hydrogen concentration.
Phosphorescence of Manganese(II) in Single Crystals of [Mn(CO(NH2)2)6](ClO4)2
Authors: Koglin E. , Schenk H. J.
Published: February 2015

The 4T1g(t4
2g e1
g) → 6A1g(t3
2g e2
g) phosphorescence spectrum of manganese (II) in single crystals of

[Mn(CO(NH2)2)6] (ClO4)2

has been recorded in the temperature range of 4.2 to 298 K. With decreasing temperature the emission maximum is shifted from 17138 cm-1 (298 K) to 16809 cm-1 (4.2 K). This red shift points to a linear thermal expansion coefficient of α = 24 · 10-6 K-1. Crystal field parameters of Dq = 748 cm-1 and B = 827cm-1 have been calculated from the room temperature absorption and excitation spectra.
On the Thermal Behaviour of Some Alkali Branched Alkanoates. Note II
Authors: Sanesi M. , Ferloni P. , Spinolo G. , Tonelli P. L.
Published: February 2015

The investigation on phase relationships and pertinent heat effects in branched alkali alkanoates was extended to lithium, sodium and potassium 2,2-dimethylpropanoates, 2-ethylbutanoates and 3,3-dimethylbutanoates. The results allow to discuss some aspects of the thermal behaviour of these salts, among which only the potassium ones can still exist as mesomorphic liquids.
Kinetics of the Rapid Reaction Cl2 + 2Br- → Br2 + 2Cl- in Aqueous Solution
Authors: Rao T. S. , Mali S. I. , Dangat V. T.
Published: February 2015

A competition technique has been employed to study the kinetics of the rapid reaction Cl2+2Br- → Br2+ 2Cl- in aqueous solution. The specific rate at 25 °C and the energy of activation for the reaction are found to be 88.8 M-1
s
-1 and 71.1 kj mole-1, respectively.