bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Molecular Dynamics Study of Aqueous Solutions
Authors: Bopp P. , Dietz W. , Heinzinger K. 
Published: February 2015

Abstract
The central force model for water has been employed in a molecular dynamics simulation of a 2.2 molal NaCl solution. The structural properties of the solution obtained are compared with results of previous simulations where the ST2 model of water was used. Preliminary results on the influence of the ions on the water molecule geometry in the hydration shells are reported. The spectral densities calculated from the hydrogen velocity autocorrelation functions by Fourier transformation indicate differences in the librational and vibrational frequencies between bulk water and hydration water of Na+ and Cl-.
Local States in One-Dimensional Symmetrical Quantum Systems
Authors: Brickmann Jürgen 
Published: February 2015

Abstract
Local quantum states, which play an important role in quantum dynamical treatments, are expanded analytically with respect to a basis of eigen functions of a symmetrical Hamiltonian ℋ̂(x) = ℋ̂(- x). Exact local states (ELS) in one-dimensional symmetrical quantum systems are therein defined as quantum states which are local eigenstates of the Hamiltonian ℋ̂(x) on one half space ℝ+ or ℝ- and are identically equal to zero on the other half space. Local properties like the projection operator on one half space can be given in terms of ELS-basis, but it is shown that the energy moments 〈(〈ℋ̂ 〉 - 〈ℋ̂)k〉 with respect to the ELS do not converge. Consequently, if one uses the ELS as quasistationary initial states, as has been done recently by some authors [5], the lifetimes of these states cannot be estimated from time energy uncertainty relation using the second energy moment as an energy uncertainty measure. A harmonic oscillator system and a symmetrical double oscillator are treated as examples.
Studies of the Chaotic Behaviour in the Peroxidase-Oxidase Reaction
Authors: Olsen Lars F. 
Published: February 2015

Abstract
This note presents experimental results with an enzyme-catalysed reaction with a continuous supply of the substrates in which we observe a transition from periodic behaviour to apparently nonperiodic behaviour by decreasing the enzyme concentration. A model of the reaction is also described. This model, based only on elementary reaction steps, can simulate the periodic behaviour observed experimentally. By changing only one rate constant the behaviour changes from periodic to quasi-periodic behaviour. The work of earlier investigators suggests that such quasiperiodic behaviour (toroidal oscillations) is a step towards chaotic behaviour.
Molekül-und Kristallstrukturen des Dibrom- und Dijodmaleinsäurethioanhydrids Zum Verständnis der Korrelation zwischen / Crystal Structures of Dibrom- and Diiod Maleic Acid Thioanhydride
Authors: Gonschorek Walter 
Published: February 2015

Abstract
The molecular and crystal structures of dibrom maleic acid thioanhydride and diiod maleic acid thioanhydride have been determined by means of single-crystal X-ray intensities. The crystal structures are isomorphous and have the space group P41212 (enantiomorphous with P43212). The lattice constants are a = 7.543 Å, c = 12.155 Å (DBMTA) and a = 7.816 Å, c = 12.348 Å (DIMTA). The five-membered rings of the molecules are planar with maximum deviations of 0.003 Å (DBMTA) and 0.005 Å (DIMTA). Adjacent molecules are held together by van-der-Waals-forces.
Energy Transfer in Dye Solutions of Micellar Structure
Authors: Marszałek T. , Baczyński A. , Orzeszko W. , Rozpłoch A. 
Published: February 2015

Abstract
A theoretical description of micellar dye solutions containing donors and acceptors is developed. It is proved experimentally that the luminescent characteristics of Water-Triton X-100 solutions of Coumarine 1 as a donor and Rhodamine 6G as an acceptor are consistent with the proposed theory. It is shown that the probability of energy transfer between dye molecules and the number of detergent molecules in a micelle may be obtained.
Proton Relaxation in Various Copper (II) Complexes and Determination of the Singlet-Triplet Separation
Authors: Jannek H. D. , Midler-Warmuth W. 
Published: February 2015

Abstract
Proton spin-lattice relaxation rates have been measured at 30 MHz as a function of temperature for a large number of dimeric copper complexes with the ligands 8-hydroxyquinoline, pyridine-N-oxide, methyl and dimethyl pyridine-N-oxide, and quinoline-N-oxide. Two carboxylates and adducts of several complexes with various solvents have also been studied. In contrast to some compounds with a normal magnetic behaviour, for most complexes a temperature dependent relaxation has been observed which agrees well with the concept of a weak antiferromagnetic interaction between the two Cu2+ ions. The singlet-triplet separations or exchange integrals have been determined.
The Projectile of the Lappajärvi Impact Crater
Authors: Göbel Elke , Reimold Uwe , Baddenhausen Hildegard , Palme Herbert 
Published: February 2015

Abstract
Two impact melt samples from the Lappajärvi crater (Scandinavia) are highly enriched in siderophile elements, such as Ir, Re, and Os. This indicates the presence of a meteoritic component. The simultaneous enrichments of Ni, Co, Cr, and Se suggest a chondritic projectile. Because of the relatively large indigenous contributions to Ni, Co, and Cr, it is not possible to distinguish between a normal and a carbonaceous chondrite. The high concentrations of relatively volatile elements could point towards a volatile-rich projectile.
The two melt samples have high Re/Ir ratios compared to chondritic ratios. Enrichment of Re relative to Ir is very unusual in terrestrial impact melts. Loss of Re, because of volatilisation under oxidizing conditions or by weathering is frequently observed.
The high Re/Ir ratios and the high abundances of relatively volatile elements either indicate the presence of a volatile rich phase or they characterize a type of meteorite, which has not been sampled. Some lunar highland rocks have a pattern of meteoritic elements rather similar to that observed for the Lappajärvi meteorite.
The Lappajärvi crater is, after Rocheehouart, the second European crater where a significant amount of meteoritic component has been found.
A melt sample from the Lake St. Martin crater (Manitoba), did not show any enrichment in meteoritic elements.
High Energy Radiation-Induced Aggregation of Plasma Proteins. Time Resolved Light Scattering Measurements
Authors: Kihara H. , Schnabel W. 
Published: February 2015

Abstract
Human immunoglobulin (IgG), bovine fibrinogen and bovine serum albumin were irradiated at room temperature with short pulses (50 ns to 2 μs) of 16 MeV electrons in 0.2 M NaClO4 solution containing phosphate buffer (pH 7.5). In the presence of N2O the intensity of light (LSI) scattered by the protein solutions increased after the pulse indicating aggregation. The latter process originates from the attack of protein molecules by OH radicals (aggregation is impeded by t-butanol and augmented by N2O). Upon plotting the relative increase of LSI vs. log time (after the pulse) sigmoidally shaped curves were obtained.
From these findings and results of optical absorption measurements the following is inferred: Aggregation occurs as a consequence of chemical alterations of the protein molecules induced by the attack by OH radicals. The transient species formed during and a few pis after the pulse are reacting within a period of several ms. At the end of this period the formation of aggregates starts. It is concluded that the primary radiation chemical process consists (among others) in the generation of nuclcation sites. The latter subsequently initiate aggregation processes.
63Cu FT-NMR Studies of Tetrahedral Copper(I)-Phosphorus Complexes
Authors: Kroneck Peter , Lutz Otto , Nolle Alfons , Oehler Horst 
Published: February 2015

Abstract
Tetrahedrally coordinated copper(I) complexes CuL4X have been synthesized, L being P(OR)3, PR3 or P(R)n(OR)3-n, and X being a non-coordinating anion such as perchlorate or tetrafluoroborate. Depending on the nature of the bound phosphorus ligand the Cu(I) complexes give well resolved 63Cu NMR spectra including a quintet signal due to spin-spin coupling between 63Cu and 31P. The 63Cu NMR spectra have been analyzed with reference to the chemical shift δ, the shielding constant σ* (given on an absolute atomic scale), the linewidth ⊿v, and the coupling constant J(63Cu-31P). Generally, the relative magnitude of these NMR parameters are in satisfactory agreement with results reported for isoelectronic Ni(O) complexes with the phosphorus ligands mentioned above. Furthermore, the NMR properties of the Cu(I) compounds are discussed in terms of σ-donor or π-acceptor capacities of the ligands coordinated, and stereochemical properties of the complexes.
Ermittlung der Elektronenaffinitäten von Maleinsäureanhydrid, -thioanhydrid, -imid und einiger ihrer disubstituierten Halogen- derivate über CT-Messungen und ihre semiempirische Berechnung (MINDO/3)
Authors: Fleischhauer Jörg , Asaad Adel N. 
Published: February 2015

Abstract
Using Mulliken’s theory of intermolecular interactions the electron affinities of some cyclic olefines (electron acceptors) have been determined by measurement of the charge transfer energies of their complexes with the electron donors 2,5-dimethyl-2,4-hexadiene and hexamethylbenzene. These electron affinities are compared with MINDO/3-results. It is investigated whether a correlation of the experimental affinities and the calculated π-HOMO-energies is possible. Finally the expected dienophilicities of the olefines are discussed.
Formation of BrO2 in the Belousov-Zhabotinsky-System- Investigation of the Ce3+ /BrO3
--Reaction*
Authors: Försterling H.-D. , Lamberz H. , Schreiber H. 
Published: February 2015

Abstract
The reaction between Ce3+ and bromate was studied in sulfuric acid solution using a dual wavelength spectrometer. From the spectral dependence of the absorbance in the region from 450 to 600 nm it is concluded that BrO2 is an intermediate of the reaction. The kinetics of formation and decay of BrO2 is compared to theoretical models.
Seven Shock-transformed Hexahedrites, Sensitive to Grainboundary Corrosion
Authors: Buchwald V. F. 
Published: February 2015

Abstract
Seven polycrystalline iron meteorites (Forsyth County, Holland's Store, Wathena, Pima Co., Chico Mountains, Kopjes Vlei and Mejillones), of bulk composition as normal hexahedrites of group II A, are shown to be severely altered hexahedrites. Mic-roprobe examination and various heat treatments of synthetic alloys support the conclusion that the meteorites after a primary slow cooling were subjected to shock-reheating above 800°C. Thereby the following transformations took place a-α-γ->α2->α, and an unequilibrated structure, very sensitive to grain-boundary corrosion was formed.
Laserspectroscopic Investigations in the Configuration 5d6s6p of Lu I
Authors: Kwiatkowski M. , Teppner U. , Zimmermann P. 
Published: February 2015

Abstract
In an atomic beam of Lu, six levels of the configuration 5d 6s 6p in the energy range 18000 to 23000 cm-1 were selectively populated with the light of a pulsed dye laser. Time resolved observation of the recmitted resonance light was used to deduce the lifetimes of the excited levels.
Correlation Between Structure and Phonon Spectra of Linear Polyiodide Chains in Tl6I6M2/n
n+(I4)2-, [M = Pb, Ag, Au, (Bi0.5 Tl0. 5)]
Authors: Stolz H. J. , Trageser G. 
Published: February 2015

Abstract
Raman-and IR-spectra of four compounds of the general composition Tl6I6M2/n
n+(I4) [n: formal valence of the M-atom, M = Ag, Au, Pb and (Bi0.5Tl0.5)] were investigated in order to identify the polyiodide species present. In accordance with structural results comparable amounts of I4
2-and I3
-/I--groups were found for M = Ag, Pb and (Bi0.5Tl0.5), while in Tl6I6Au2(I4) I3
-/I--groups predominate.
Über das magnetische Verhalten von Cs2MHoF6 (M = Na, K, Rb)
Authors: Urland W. 
Published: February 2015

Abstract
The magnetic behaviour of CS2MHoF6 (M = Na, K, Rb) has been studied in the temperature range between 3.2 and 251.3 K. The magnetic data are interpreted by means of a previously developed model in which the influence of the crystal field is theoretically described by the angular overlap model. Values of the angular overlap parameters eσ(R) and eπ(R) cannot be determined unequivocally. The energy values of the crystal-field levels of the 5I8 ground state are calculated.
Diffusion Coefficients of Rb+ and Cs+ Ions in Molten Nitrate Systems
Authors: Odawara O. , Kwak Jan C. T. , Ketelaar J. A. A. 
Published: February 2015

Abstract
The tracer diffusion coefficients of 86Rb and 137Cs ions in the molten (Li-Na)NO3, (Li-K)NO3, (Li-Rb)NO3, and (Li-Cs)NO3 systems have been measured by means of a paper strip method. Results from the paper strip method in some pure nitrates are compared with the results from capillary and optical interferometric methods. With increasing concentration of LiNO3, the diffusion coefficients at 350°C are found to decrease in the (Li-Na)NO3 system and to increase in the (Li-K)NO3, (Li-Rb)NO3, and (Li-Cs)NO3 systems. For 86 Rb in (Li-K)NO3 an increase is followed by a decrease. These findings are discussed by taking into consideration the free space in the solvent system and the ionic interaction between the diffusing and the surrounding ions.
When do Projections Commute?
Authors: Rehder W. 
Published: February 2015

Abstract
Necessary and sufficient conditions for commutativity of two projections in Hilbert space are given through properties of so-called conditional connectives which are derived from the conditional probability operator PQP. This approach unifies most of the known proofs, provides a few new criteria, and permits certain suggestive interpretations for compound properties of quantum-mechanical systems.
Microwave Spectrum of Ethyl Iodid: Internal Rotation Analysis
Authors: Boucher D. , Dubrulle A. , Demaison J. 
Published: February 2015

Abstract
The rotational spectra of the first excited state of the methyl torsion and the CCI-in plane deformation of CH3CH2I have been studied. A Coriolis interaction between these two modes has been found. Splittings of transitions in the first excited torsional state show that the barrier hindering internal rotation of the methyl group is 3.62 kcal/mole. This value agrees quite well with the value previously reported from Raman studies. It is internally consistent and similar to the other ethyl halides.
Anisotrope Fluoreszenz langgestreckter Moleküle in Lösungsmitteln unterschiedlicher Viskosität
Authors: Kawski A. , Kukielski J. , Bałuk P. , Lenczewska M. 
Published: February 2015

Abstract
The emission anisotropics (r) of the fluorescence of the prolate molecules (whose emission transition moments are parallel to the long axis) 4-dimethylamino-4'-cyanostilbene, 4-methoxy-4'-nitrostilbene, 4-dimethylamino-4'-diphenylphosphinoxidstilbene, 4-dimethylamino-4'-bromstilbene and pbis[ 2- (5-α-naphthyloxazolyl) ] -benzene in solvents of different viscosities {η) have been studied. Also for these substances the non-linear dependence of 1/r on T/η was confirmed. This non-linearity in the low viscosity range can be explained by the assumption that the prolate luminescent molecules perform irregular rotational motions within a solid angle smaller than 90°. Effective volumes and rotational relaxation times for the different molecules in the different solvents were obtained.
ESR-Untersuchungen an antiferromagnetischem CrN zum Einfluß der Temperatur auf die Austausch-Wechselwirkung / ESR-Investigation on Antiferromagnetic CrN Concerning the Influence of Temperature on the Exchange-Interaction
Authors: Dräger K. , Gerling R. 
Published: February 2015

Abstract
The ESR-behaviour of antiferromagnetic and almost stoechiometric CrN is thoroughly investigated above its Neél-point. For polycrystalline samples a spectroscopic splitting factor g =1.965 and a differential line width ⊿B = 56,7 mT is measured at room temperature. All resonance lines exhibit Lorentzian character to a high degree.
In the temperature range between 300 K and 520 K the ESR-intensity can satisfactorily be described by a model of local ordering. Its binding energy is computed to be about ⊿E = 500 ± 20 cm-1. A more refined analysis shows a systematic change of ⊿E with temperature and a discrepancy between the Neel-point TN and the temperature Ts characterizing a singular behaviour of the line width ⊿B. Apart from these deviations originating in a magnetic ordering of the fourth kind, the cluster-model gives an isotropic exchange between next nearest neighbours of J2 = -33.2 cm-1. This result is confirmed by molecular field computations.
A Molecular Dynamics Simulation of Molten (Li-Rb)Cl Implying the Chemla Effect of Mobilities
Authors: Okada Isao , Takagi Ryuzo , Kawamura Kazutaka 
Published: February 2015

Abstract
A new transport property, the self-exchange velocity (SEV) of neighbouring unlike ions, has been evaluated from molecular dynamics simulations of molten LiCl, RbCl and LiRbCl2 at 1100 K and the mixture at 750 K. From the increase of the SEV's in the order Rb+ (pure salt) <Li+ (mixture) < Rb+ (mixture) < Li+ (pure salt), it is conjectured that there is a strong correlation between the SEV’s and the internal mobilities. An interpretation of the Chemla effect in its dependence on temperature is given. The pair correlation functions and the self-diffusion coefficients are also calculated and discussed.
Molybdates Solid State Synthesis: The MgO—MoO3 System
Authors: Massarotti V. , Flor G. , Marini A. , Riccardi R. 
Published: February 2015

Abstract
The formation reaction of Mg2Mo3O11 from MgO (single crystal) and MoO3 (pellet) has been investigated in the temperature range 873-973 K.
Supported by an analysis of the transport properties a mechanism is proposed involving a unidirectional transport of Mo6+ via V6′
Mo and of oxygen via gas phase.
The transport properties of MgMoO4 (the other intermediate compound in the system MgO-MoO3) were also studied and the results were found to agree with the mechanism observed in a previous work on the basis of kinetic and structural considerations.
Selectivity in Ketenimine Cycloadditions. Photoelectron Hel Spectra of Ketenimines
Authors: Bernardi Fernando , Bottoni Andrea , Ballaglia Arturo , Distefano Giuseppe , Dondoni Alessandro 
Published: February 2015

Abstract
The first few bands in the photoelectron (Hel) spectra of ketenimines R1R2C-C=NR3(R1,R2=H, CH3, C5H6, CH2=CH; R3=alkyl or aryl group) are assigned to the corresponding molecular orbitals. The assignment is based on SCF-MO calculations made at three different levels (CNDO/2, ab-initio STO-3C and 4-31G) coupled with perturbational molecular orbital analyses.
The π-orbitals of the unsaturated substituents are found to interact with one of the two perpendicular π-electron systems of the〉C=C=N- residue, the critical factor being the position of attack of the substituent.
The relevance of these results on the site selectivity observed in cycloaddition reactions of these species is discussed.
Patterns of Spatial Organization in Growth
Authors: Marek Miloš , Kubíček Milan 
Published: February 2015

Abstract
Patterns of spatial concentration profiles arising in one-dimensional reaction-diffusion systems in the course of variations of the characteristic dimension of the system (growth) are analyzed. The spatial profiles established and their changes depend on the character of the steady state pattern dependence on length. If the families of solutions (spatial profiles) arising at L = nL1*, nL2* form closed curves, and a slow (quasistationary) linear or exponential increase of the characteristic dimension is considered, then subsequently more complex patterns of spatial concentration profiles appear regularly in a reproducible way. The system keeps every established pattern for a fixed interval of time which depends on the rate of growth. Implications for two different interpretations of the morphogen gradient formation in the models of embryogenesis are discused.
Investigation of Transient Dispersion and Absorption Phenomena with a Bridge Type Superheterodyne Microwave Spectrometer
Authors: Bomsdorf H. , Dreizler H. , Mäder H. 
Published: February 2015

A bridge type superhet spectrometer for time resolved investigation of rotational relaxation is described. Allowing the application of both Stark- and pump-modulation techniques the arrangement may be used for single and double resonance experiments, showing a lot of advantages compared with a conventional Stark- or double resonance-spectrometer. These features are discussed in detail.
By means of a MW-pulse method the following two-level experiments have been carried out. The rotational relaxation time T2 was measured by detection of M-unresolved transient emission signals for J = 1 - 2 of 16O12C32S, 16O12C34S and 16O13C32S in natural isotopic abundance and for eight transitions of SO2 up to J = 43. The signals of transient dispersion were detected and compared with those of transient absorption. Their theoretical description in terms of the two-level Bloch equations is discussed.
Shift of the Til 535.0 nm line by hydrogen
Authors: Lisicki E. 
Published: February 2015

Abstract
The shift by hydrogen of the 535.0 nm T1 line resulting from photodissociation of thallium iodide was investigated at low densities. A linear variation of the shift with the hydrogen density was found with a shift coefficient of -(0.443 ± 0.012) X 10-20 cm-1 /(molecules cm-3).
Die spezifische Verbreiterung der FeI-Resonanzlinie 3859,91 Å durch Stöße mit Argonatomen bei hohen Temperaturen / Specific Line-Broadening of the Iron-Resonance-Line 3859,91 Å by Collisions with Argon Atoms at high Temperatures
Authors: Steinwandel J. , Joos V. E. , Hauser M. , Dietz Th. 
Published: February 2015

Abstract
The specific line-broadening cross section of the FeI-resonance transition at 3859.91 Å by collision with argon atoms was measured in the temperature range of 2000 K ≦ T ≦ 3500 K in a shock tube.
Driving gas was Helium, shock wave carrier gas and collision partner was Argon. The free iron atoms were produced by the unimolecular decomposition of ironpentacarbonyl in the front of the incident shock wave.
The initially produced iron condensate evaporates completely in the reflected shock wave to form free atoms. They are present behind the reflected shock wave in the form of a thermodynamically well defined undersaturated vapour. Thermodynamic quantities of the vapour do not change during the observation time.
The line-broadening cross section σL(T) was measured by the method of integral atomic line absorption spectroscopy on the FeI-resonance line at 3859.91 Å to (10.05 ± 1.40) x 10-15 cm2 . Temperature variations in σL are smaller than experimental errors.