bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract
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

Abstract
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.
Elektronenanregungsenergieübergang zwischen gleichartigen Molekülen in Lösung / Electronic Excitation Energy Transfer among like Molecules in Solution
Authors: Kamiński J. , Kawski A. 
Published: February 2015

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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.
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.
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.
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.
Energy Principle for Dissipative Two-fluid Plasmas
Authors: Tasso H. 
Published: February 2015

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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.
High-Dilution Diffusion of Tl+ in Molten NaNO3, KNO3 and RbNO3 Studied by Wave-Front-Shearing Interferometry
Authors: Okada Isao , Gustafsson Silas E. 
Published: February 2015

The high-dilution diffusion of Tl+ in molten NaNO3 , KNO3 and RbNO3 has been measured with wave-front-shearing interferometry. For very low concentrations of TlNO3 the results are
D = 6.21×10-8 exp [-(18400± 800)/RT] in NaNO3 (316-387 °C),
D = 5.39×10-8 exp [-(18800±1400)/RT] in KNO3 (341-408 °C),
D = 1.87×10-7 exp [-(25800±2200)JRT] in RbNO3 (327-419°C),
where D is the diffusion coefficient in m2 s-1, R the gas constant in J K-1 mol-1 and T the temperature in K.
Comparisons are made with high-dilution diffusion of Na+, K+, Rb+, Cs+ and Ag+ ions in alkali nitrates, and it is found that both Ag+ and Tl+ diffuse faster than expected if the mass and the ionic radius were the sole parameters of importance, i. e. other parameters such as the polarizability also have an influence on the diffusion rate of an ion. For the system NaNO3 - TlNO3 , the interdiffusion coefficient has also been measured at 88.8, 73.8, 51.5 and 31.6 mol % NaNO3 .
The Microwave Spectrum of Oxazole
Authors: Kumar Anil , Sheridan John , Stiefvater Otto L. 
Published: February 2015

The dipole moments and the quadrupole coupling constants of the normal and the three mono-deuterated species of oxazole have been measured. The dipole moment of 1.50 ± 0.03 D is found to deviate by 10.8° from the external bisector of the CNC angle towards the C(2) carbon atom. The principal values of the quadrupole coupling tensor are determined as Xzz = -4.04 ± 0.02 MHz and Xxx - 1-66 ± 0.02 MHz along the axes in the molecular plane, so that the gradient perpendicular to this plane is Xyy = 2.38 MHz. The direction of the largest gradient deviates by 5.7° from the external bisector of the CNC angle towards the carbon atom C(4).
An attempt is made to correlate these results and the geometry of oxazole with the electron distribution in this molecule
Ionization of Unpolar Molecules by Alkali Ion Attachment on the Surface of Electrolytic Solutions Exposed to High Electric Fields
Authors: Röllgen F. W. , Ott K. H. 
Published: February 2015

Abstract
It is shown that mixtures of salts with low vapor pressure organic compounds deposited on field anodes can be used for surface ionization of paraffins by Li+ and Na+ ion attachment. The highest ionization efficiencies were obtained with emulsifying agents such as Tweens® mixed with Lil.
Resonant Interaction of Surface Plasmons with a Dye Monolayer
Authors: Wähling G. , Möbius D. , Raether H. 
Published: February 2015

The interaction of surface plasmons with a dye monolayer having a rather small absorption band is discussed in this paper. Applying the ATR method surface plasmons were excited on a silver surface covered with a monolayer of arachidate (26.8 Å) and a monolayer of the dye.
The position, half-width and the depth of the reflection minimum are strongly dependent on the applied wavelength in the region of the absorption line. The essential features of the measured dependencies can be explained by a simple oscillator model.
NMR Spectra of Alkali and Halogen Nuclei in Alkali and Halogen Salts
Authors: Gauß W. , Günther S. , Haase A. R. , Kerber M. , Kessler D. , Kronenbitter J. , Krüger H. , Lutz O. , Nolle A. , Schrade P. , Schüle M. , Siegloch G. E. 
Published: February 2015

NMR signals of 7Li, 23Na, 35Cl, 39K, 79Br, 87Rb and 127I have been measured in various alkali and halogen salt powders relative to well defined aqueous solutions. With the known shielding constants of some of these solutions the nuclear magnetic shielding constants of the alkali and chlorine nuclei in crystalline powders were evaluated in the atomic reference scale. The theoretical values of the shielding constants in alkali halides do not agree even in the order of magnitude with the experimental ones in some cases.
For 23Na first-order and second-order quadrupole patterns have been observed and the quadrupole coupling constants are given.
Die Kinetik des thermischen Zerfalls von ClNO2 / Thermal Decomposition of ClNO2
Authors: Knauth H.-D. , Martin H. 
Published: February 2015

ClNO2 decomposes incompletely at temperatures between 353 K and 373 K in the nonpolar inert solvent C7F15Cl according to
2 ClNO2=2 NO2+Cl2. (a)
Some ClNO is formed as by-product according to
2 ClNO2 = 2 ClNO+O2 . (b)
The reactions were followed photometrically by the arising NO2 . The time dependence of the brutto-reaction is described on the basis of the reaction scheme
ClNO2⇄NO2+Cl (1, - 1); NO3+NO2⇄NO+O2+NO2 (5, - 5);
ClNO2+ClNO2⇄Cl2+2NO2 (2, - 2); NO+ClNO2⇄ClNO+NO2 (6, - 6);
Cl+ClNO2⇄Cl2+NO2 (3, - 3); ClNO+ClNO2⇄NO±Cl2+NO2 (7, - 7);
NO2+ClNO2⇄NO3±ClNO (4, - 4); Cl+ClNO⇄Cl2+NO (8, - 8).
Arrhenius parameters for the steps (1) and (2) were obtained:
A1/s-1 = 1016.47±0.78, E1/kJ mol-1 = 152.3 ± 5.4;
A2/cm3 mol-1 s-1 = 1012.99±0.02 E2/kJ mol-1 = 88.7 ± 0.8.
The other parameters entering the rate equations were determined at 373 K as k-1/k3 = 1.5 ± 0.3; k4/cm3 mol-1 s-1 = 0.17; k7/cm3 mol-1 s-1 = 11.2. The enthalpies and entropies of the overall reactions (a), (b) and N2O4 = 2 NO2 (c) were measured directly (c) or indirectly:
(a) (b) (c)
⊿RH/kJ mol-1 46.4 83.7 65.3
⊿RS/J K -1 mol-1 61.8 85.7 97.8
(standard state 1 mol cm-3, T = 363 K).
Former investigations of the reaction in the gas phase and in solution which were interpreted exceptionally by step (1) followed by the fast step (3) are now interpreted on the basis of the new reaction scheme discussed here and are found to be consistent with it.
Structure of Molten Sn-Zn-Alloys by Means of Neutron Diffraction
Authors: Knoll Walter , Steeb Siegfried 
Published: February 2015

Abstract
Neutron diffraction experiments were performed with four molten Sn-Zn-alloys and the two molten elements Sn and Zn. The total structure factors and the pair correlation functions are given. The observed small angle scattering leads to the result that pairs of equal atoms predominate within the range of medium concentrations.
Formation of Cyanopolyynes in Gas Discharges
Authors: Winnewisser G. , Creswell R. A. , Winnewisser M. , Winnewisser M. 
Published: February 2015

Abstract
Cyanodiacetylene, H(C ≡ C)2 CN has been produced by a radiofrequency discharge in a mixture of acetylene, HCCH, and hydrogen cyanide, HCN. This reaction is of astrophysical importance, since it lends support to the possibility of the ion-molecule formation scheme of producing long carbon chain molecules in interstellar sources. From a measurement of the J = 4←3 transition of HC5N the nuclear quadrupole coupling constant eqQ = - 4.242 (30) MHz was determined.
Microwave Spectrum of (SiH3)2X, X = O,S, r0-Structure, Molecular Electric Dipolemoment and Barrier to Internal Rotation of Disilylsulfide
Authors: Dössel K. F. , Sutter D. H. 
Published: February 2015

Abstract
The rotational spectrum of SiH3-S-SiH3 in its vib-torsional ground state has been investigated in the frequency range between 8 and 40 GHz. From the absolute frequencies and torsional splittings a rigid-top-rigid-frame r0-structure could be derived. The molecular electric dipole moment was determined from the second order Stark effect of some AA-species rotational transitions. The analysis of the microwave spectrum of the related molecule SiH3-O-SiH3 was yet unsuccessful. However several features of the observed spectrum rend support to the idea of a “quasi-linear” double rotor molecule with a relatively low energy hump for the linear configuration of the Si-O-Si-chain.
Heuristic Considerations Suggesting a Role for Electron Pairing in Thermodynamically Consistent Pathways of Enzyme Catalysis
Authors: Conrad Michael 
Published: February 2015

Abstract
Nuclear motions accompanying enzyme catalysis are described in terms of a hypothetical reaction mechanism in which instabilities of electronic structure arise from short-lived pairing resonances of parallel spin electrons. A pairing interaction is proposed which has its basis in confinement constraints imposed by complex formation.
Electronic Theory for Cleaved Alloys: Effects of Off-Diagonal Disorder
Authors: Masuda Kin-ichi 
Published: February 2015

Abstract
The tight-binding type theory for cleaved alloys by Bennemann et al. has been extended to include the effects of the random transfer integrals (off-diagonal disorder). The chemisorption and segregation behavior of cleaved alloys is investigated in detail including both the diagonal and off-diagonal disorder. It is demonstrated that the effects of the off-diagonal disorder are very important for the electronic properties of cleaved alloys. The theory has further been used to study the electronic structure of metal surfaces with substitutional disorder as well as to investigate the changes in the density of states due to the order-disorder phase transition in chemisorbed layers.