bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Ausmessung des Brom-Affinitätskontinuums und Bestimmung der Detachment-und Attachment-Querschnitte
Authors: Frank H. , Neiger M. , Popp H.-P. 
Published: February 2015

Abstract
A wall stabilized low-current cylindric arc was used to produce the radiation of the negative Bromine-ions. The radiation consists of an affinity-continuum with a long-wave threshold of 3682 Å, yielding an electron affinity for Bromine of 3.366 eV, and of an intense electron-atom Bremsstrahlung in the visible. Intensity measurements of the continua allow the determination of the photo-detachment-and attachment-cross-sections of Bromine and also the determination of the mean elastic cross-section of electrons against Bromine atoms.
Zur Deutung der kernmagnetischen Relaxation in Proteinlösungen
Authors: Kimmich R. , Noack F. 
Published: February 2015

Abstract
Measurements of longitudinal and transversal proton relaxation times in both H2O and mixed H2O/D2O protein solutions show a low-frequency as well as a high-frequency dispersion of the longitudinal relaxation time and a nonexponential two-phase transversal relaxation. These results are discussed qualitatively in terms of “rigid” and “mobile” relaxation centers within the protein molecules.
Quantenlogische Interpretation orthokomplementärer quasimodularer Verbände
Authors: Mittelstaedt P. 
Published: February 2015

Abstract
In dem orthokomplementären, quasimodularen Verband der Teilräume des Hilbert-Raumes lassen sich die Relationen der Implikation und Kommensurabilität als Operationen definieren. Dadurch wird es möglich, diesen Verband als einen quantenlogischen Aussagenkalkül zu interpretieren. Die Begriffe Implikation und Kommensurabilität stimmen dabei überein mit den im Rahmen der Logik operativ definierten entsprechenden Begriffen.
Hyperfeinstruktur des Rotationsspektrums bei zwei vergleichbaren Quadrupolkopplungskonstanten: Inj
Authors: Schenk B. , Tiemann E. , Hoeft J. 
Published: February 2015

Abstract
Frequenzen und relative Intensitäten der Hyperfeinstrukturlinien eines Rotationsübergangs eines zweiatomigen Moleküls, dessen beide Quadrupolwechselwirkungsenergien vergleichbar mit der Rota-tionsenergie sind, werden exakt berechnet. Aus den Rotationsübergängen J = 2 → 3, 14→15, 15 →16, 16→17 und 17→18 von 115ln 127J wurden die Dunham-Koeffizienten und Kernquadru-polkopplungskonstanten dieses Moleküls bestimmt:
y01 = 1105,246(15) MHz,
Y21= 2,4 (6) kHz,
Y11= -3,121 (6) MHz,
Y02= -227 (13) Hz,
e qv Q(115ln) = - 607,5 (5) +0,8 (8) (v+1/2) MHz,
e qv Q(127J) = -386,4 (4) -2,3 (8) (v +1 /2) MHz.
A Comment on Zeeman Effects in Rotation Spectra
Authors: Howard B.J. , Moss R.E. 
Published: February 2015

Abstract
Recently SUTTER et al. 1 obtained a Hamiltonian for a molecule in the presence of a constant external elec-tromagnetic field. (A similar Hamiltonian has been de-veloped 2 , but including molecular vibrations, relativis-tic corrections and allowance for the fact that the mo-lecular centre of gravity differs from the nuclear centre of gravity.) We believe that the Hamiltonian of Sutter et al. is not correct, since they make two errors of principle in performing their gauge transformation. They start with a Lagrangian expressed in terms of the particle positions, rn\ in a space-fixed coordinate system. Each particle is associated with an external vector potential,-^«' = rn', where H is the constant external magnetic field. At this stage a gauge transfor-mation may be performed: An'-+An'-VnX, (1)
Decay Schemes of Mo91 and Mo91m
Authors: De Barros S. , Maurenzig P. R. , Baptista G. , Canto L. F. , De Pinho A. G. , Jeronymo J. M. F. 
Published: February 2015

Abstract
Seven previously unreported gamma rays in the decay of Mo91
g-s -were observed and had their energy and intensity measured.
For Mo91m two new gamma rays were observed and the levels fed by its decay were identified with l=1 levels found by (He3, d) reaction.
Thermodynamische Analyse kalorimetrischer Messungen an Aluminium und Wolfram im Bereich hoher Temperaturen
Authors: Schmidt Udo , Vollmer Otmar , Kohlhaas Rudolf 
Published: February 2015

Abstract
Mit Hilfe eines quasi-adiabatisch und kontinuierlich arbeitenden Hochtemperatur-Kalori-meters wurde die spezifische Wärme von Aluminium und Wolfram sowie die Schmelzwärme von Aluminium gemessen. Eine atomistische thermodynamische Analyse ermöglicht eine Aussage über den Beitrag der anharmonischen Gitterschwingungen zur spezifischen Wärme bei konstantem Volumen.
Potentialflächen angeregter Zustände von H3 / Potential-Energy Surfaces for Excited States of H3
Authors: Frenkel E. 
Published: February 2015

Abstract
Ab-initio calculations for low-lying states of H3 in C2v and D∞h symmetry are reported. It is shown that the potential energy surfaces of some states dissociating to H2(X, 1Σg
+) and H (n = 2) possess deep minima in D3h symmetry. The results are used to discuss recent experiments on the reaction of H2 with metastable H.
Isotope Effects in Close-Packed Metals and in Alkali Halides
Authors: Brown R. C. , Worster J. , March N. H. , Perrin R. C. , Bullough R. 
Published: February 2015

Abstract
An expression was obtained earlier by the authors, on the basis of Vineyard's rate theory, for the sharing of the kinetic energy of a diffusing isotope at the saddlepoint with other host atoms. The theory is expressed in terms of the (imaginary) frequency of the localised vibration in which the diffusing atom at the saddlepoint is coupled to its neighbours.
Numerical results are presented for the case of a Cu isotope diffusing by the vacancy mechanism in a pure Cu lattice. The pair potential determined by Englert, Tompe and Bullough, which fits the phonon spectra and the stacking fault energy, has been employed in the calculation.
The effects of coupling between the diffusing atom and its immediate neighbours are very small with this potential. The main coupling is found to be to the eight third-nearest neighbours. Treating the vibrations of these nine atoms, a sharing of kinetic energy is found, which is in quantitative agreement with the experimentally observed isotope effect, assuming a vacancy mechanism for self­ diffusion. This situation for Cu is in marked contrast to Na, where it was shown in earlier work that the present theory could not explain the observed mass effect, assuming a vacancy mechanism for diffusion.
The diffusion of Cs in the CsCl lattice is also discussed using the same theory. Following our earlier work on NaCl, the localized normal mode considered is that in which the Cs isotope at the saddlepoint is at the centre of a square with four Cl near-neighbour ions at the vertices. A formula for the sharing of kinetic energy is derived, and it is pointed out that, as for NaCl, the force con­ stants can be obtained from the classical approach of Mott and Littleton. An argument is proposed which suggests that, as with NaCl, the sharing of kinetic energy will be small. No experimental data appear as yet to be avaialable for the CsCl structure
Die Aktivitätskoeffizienten des Hg im Indiumamalgam beim Übergang von der festen zur flüssigen Phase / The activity coefficients of hg in in-amalgams at the solid-liquid phase transition
Authors: Franck Günter 
Published: February 2015

Abstract
By 2537 Å resonance absorption the temperature dependency of mercury partial pressure of dif­ferent In-amalgams is measured. - The Hg-concentrations of the investigated amalgams are 1.9 - 20 atomic per cent. The temperature interval is 30 -160 °C. In the solid + liquid two-phase region the activity coefficient of mercury is strongly diminuted with growing temperature. For tem­peratures higher than 130 °C the Hg-vapour pressure in the two-phase region falls with growing temperature.
With the help of a generalized Clausius-Clapeyron formula for a three phase system with two components the mercury vapour pressure in the liquid + solid two-phase region is calculated. There is a good agreement with our experimental results
Zur Erweiterung der Poulet-Loudon-Näherung in der Theorie der optischen Gitterschwingungen
Authors: Merten L. , Lamprecht G. 
Published: February 2015

In einachsigen Kristallen sind die Frequenzen der sog. außerordentlichen optischen Gitterschwingungen richtungsabhängig (Richtungsdispersion). Diese Richtungsabhängigkeit wurde in der Literatur bisher fast ausnahmslos durch die Poulet-Loudon-Näherung beschrieben. Im folgenden werden zwei erweiterte Näherungslösungen angegeben. Da inzwischen auch die exakten Lösungen (im Rahmen der harmonischen Näherung) bekannt sind, läßt sich die Genauigkeit dieser beiden Näherungen wie auch der Poulet-Loudon-Näherung jetzt gut beurteilen.
Als Beispiele werden je zwei Schwingungszweige starker Richtungsdispersion von a-Quarz und dem tetragonalem BaTiO3 im einzelnen diskutiert.
Die Molekülstruktur des Chlor-Isocyanats ClNCO
Authors: Oberhammer Heinz 
Published: February 2015

Abstract
Die Molekülstruktur des Chlor-Isocyanats in der Gasphase wurde mit Hilfe der Elektronen­-beugung bestimmt. Dabei ergeben sich zwei mögliche Strukturmodelle, zwischen denen auf Grund der Elektronenbeugung alleine nicht unterschieden werden kann. Im Modell 1 ist die NCO-Gruppe linear, die N-C-und C-O-Bindungslängen weichen stark von den für ähnliche Moleküle bestimmten "Werten ab. Im Modell 2 ist die NCO-Gruppe um einen Winkel von ca. 10° geknickt, die N-C-und C-O-Bindungslängen stimmen gut mit den für ähnliche Moleküle bestimmten Werten überein. Außerdem ergibt sich für das Strukturmodell 2 ein um ca. 5° kleinerer ClNC-Winkel als für Modell 1. Unter Hinzunahme der aus mikrowellenspektroskopischen Messungen bekannten Rota­tionskonstanten kann eine Entscheidung zwischen den beiden Modellen zugunsten von Modell 2 getroffen werden. Audi semiempirische MO-Rechnungen sprechen für eine geknickte NCO-Gruppe in diesem Molekül.
Studies on the PMR Spectra of Oxetanes
Authors: Jokisaari Jukka , Rahkamaa Erkki , Malo Heikki 
Published: February 2015

Abstract
The 60 MHz PMR spectra of 2 -(4-iodophenyl) oxetane, 2-(4-bromophenyl) oxetane, 2-(4-fluoro-phenyl) oxetane, and 2-(4-chlorophenyl) oxetane have been analysed for the oxetane ring protons and the phenyl protons. In the three first mentioned compounds the spectra show a coupling of 0.46 - 0.63 Hz between the benzyl proton and the phenyl protons in ortho position relative to the oxetane ring, the other proton-proton couplings between the oxetane and phenyl parts being zero in the error limits. In the oxetane part, the halogen substituent in the para position of the phenyl ring mainly affects the chemical shifts of the protons with a slight effect on the proton-proton couplings. The ortho and meta couplings of the phenyl protons increase and the para coupling decreases with growing electronegativity of the substituent, in the order iodine, bromine, fluorine. The phenyl protons in 2-(4-chlorophenyl) oxetane produce a sharp singlet, which shows that they are chemically equivalent. This proves that chlorine and the oxetane group affect the shieldings of the phenyl protons similarly, which is supported by comparing the chemical shift differences in 2-(4-halophenyl) oxetanes to the ones in para-dihalo-substituted benzenes.
Über die Konzentrationsdepolarisation der Photolumineszenz von Lösungen
Authors: Bojarski C. , Dudkiewicz J. 
Published: February 2015

Abstract
Die Emissionsanisotropie der Photolumineszenz von Rhodamin 6 G in Wasser-Glycerin wurde im Konzentrationsbereich 5 · 10-6 bis 8 · 10-2 M/1 gemessen. Bei Konzentrationen c > 10-2 M/l wurde ein Repolarisationseffekt festgestellt. Die Meßergebnisse wurden mit der Theorie der Konzen­ trationsdepolarisation, die die Löschung der Fluoreszenz durch nicht lumineszierende Dimere berücksichtigt, verglichen.
Streuung von Ionen. II. Regenbogeneffekt bei der elastischen Streuung von Protonen an Helium, Neon, Krypton, Xenon und von He+ an Helium
Authors: Weise H.-P. , Mittmann H.-U. , Ding A. , Henglein A. 
Published: February 2015

Abstract
Differential scattering cross sections of H+ on various noble gases and of He+ on He were measured at various energies between 3 eV-80 eV. The rainbow structure and the superimposed rapid oscillations were resolved. Differential cross sections were calculated in WKB approximation and compared with experimentally obtained cross sections. Agreement was obtained by using the modified Morse potential:
U = exp{2 G1 G2(1 -ρ)} -2 exp{G1 G2(1-ρ)} , G2 = 1 for ρ>1,
whit ρ=r/rm, and U=V/ε. G2 ≠ 1 for ρ ≧1,
The fitting procedure discussed in part I was applied in order to obtain the parameters ε,rm, G1 and G2. Calculations with the modified Lennard-Jones potential described in part I gave the same values for ε and rm .
With exception of the system H+ -Xe, a single set of parameters could describe the rainbow structure and the fine structure at all ion energies. The values for ε and rm agree fairly well with ab-initio calculations. The reduced potentials have about the same shape, G1 being between 2.7 and 2.2, G2 being between 0.8 and 0.9.
In the case of H+ -Xe, ε increases significantly with decreasing proton energy, while G1 and G2 have only slightly to be changed. The potential well is narrower than for the other systems mentioned above. These effects are attributed to the crossing of the potential curves of the systems H+ -Xe and H-Xe+ .
Zum Kornwachstum beim reinen und dotierten polykristallinen Selen / Grain Growth of Pure and Doped Poly crystalline Selenium
Authors: Weyrich C. 
Published: February 2015

Abstract
Grain Growth of Pure and Doped Poly crystalline Selenium Samples of vitreous high-purity selenium as well as vitreous chlorine-and thallium-doped selenium have been brought into the polycrystalline form by annealing. The dependence of grain size on annealing time tu was measured. In high-purity selenium and in chlorine-doped selenium the mean grain diameter increases essentially ~ tu
1/2 , in thallium-doped selenium ~ tu
1/2 , as is expected from the laws of grain growth. The proportionality between electrical conductivity and specific grain surface reported by other authors could not be verified.
Diffusion Processes in TlCl
Authors: Friauf Robert J. 
Published: February 2015

Pure single crystals have been used for measurements of ionic conductivity (160° -425 °C ) , CI diffusion (275° - 415 °C ) , and Tl diffusion (290° - 400 °C ) . Conductivity measurements were made with a capacitance bridge at 1 to 10 kHz, and diffusion coefficients were obtained with radioactive tracers and the sectioning technique. It is found that D*(Cl) is 10 to 40 times larger than D* (Tl) . An empirical fit gives
D*(CI)=0.031 exp [ - (0.771 ± 0.010) /k T] ,
D*(Tl)=0.62 e x p [- (1.101 ± 0 . 0 2 0 ) /k T]
with D in cm2/s and the energy in eV. The conductivity has an activation energy of 0.76 eV for 230°-330 ° C , increasing to 0.87 eV for 375° - 425 ° C . For several reasons the conductivity is believed to be entirely ionic. The Nernst-Einstein relation is generally well obeyed, but there is a significant excess diffusion of 10 t o 15%.
The results show that the defect structure consists primarily of Schottky defects with highly mobile anion vacancies. The excess diffusion can be accounted for by the presence of up to 20% of either vacancy pairs or next nearest neighbor jumps into single vacancies; there is no clear preference for either mode. With a Schottky formation energy of 1.36 + 0.03 eV from other work, the mobility energies are 0.104 ± 0.005 eV for CI for either model, and 0.56 ± 0.04 or 0.44 ± 0.02 eV for Tl, respectively. Comparisons are made to observations of conductivity and diffusion by other workers near r o om temperature and in the melt.
Functional Quantum Theory of Free Relativistic Scalar Fields
Authors: Bauhoff W. 
Published: February 2015

Abstract
Dynamics of quantum field theory can be formulated by functional equations. Starting with the Schwinger functionals of the free scalar field, functional equations and corresponding many particle functionals are derived. To establish a complete functional quantum theory, a scalar product in functional space has to be defined as an isometric mapping of physical Hilbert space into the functional space.
Optisches Pumpen an Mangan
Authors: Assfalg A. , Fricke J. , Haas J. , Tilgner R. , Lüscher E. 
Published: February 2015

Abstract
The 6 S5/2 ground state of Mn 55 was polarized by spin exchange collisions with an optically pumped Cs-vapour. The rf induced transitions between Zeeman subleves of Mn were detected as a change in the Cs pumping light transmission. To estimate the effectiveness of direct optical pumping or of detection with resonance light the absorption probabilities for circlarly polarized light are given as functions of 〈Sz〉.
Calibration of a Slotted Disk Velocity Selector Using Supersonic Molecular Beams
Authors: Cantini P. , Dondi M. G. , Torello F. 
Published: February 2015

Abstract
A new calibration method for slotted disk velocity selectors is presented and is compared with other calibration procedures.
It is based on the measurement of the velocity distribution of a supersonic molecular beam produced by a room temperature source.
The error due to the assumed theoretical distribution and to experimental procedure is discussed. It is shown that the velocity scale is known to within 0.8%.
Binary Systems Containing Hydrocarbons IV. Miscibility Gaps in 18 Nitromethane + 1-, 2-, 3-and 4-alkenes
Authors: Ferloni Paolo , Geangu-Moisin Angela , Franzosini Paolo , Rolla Mario 
Published: February 2015

Abstract
Liquid-liquid equilibria in binary systems of nitromethane with 1-(C8-C9)-, trans-2-(C5-C9)-, trans-3-(C6-C9)-, trans-4-(C8-C9)-, 3-methyl-1-(C5)-, 2-methyl-2-(C5-C7)- and cis-2-(C6)-alkenes were investigated. Some regularities obeyed by the critical temperatures and compositions, as well as the possibility of foreseeing (on empirical basis) the two liquids region boundaries are discussed.
Optische Kern-Spin-Polarisation in Molekül-Kristallen
Authors: Schuch H. , Stehlik D. , Hausser K. H. 
Published: February 2015

This paper deals with the polarisation of nuclei in molecular crystals due to their hyperfine interaction with optically excited triplet states and excitons, a phenomenon which is termed optical nuclear polarisation (ONP).
A theory is presented which extends the mechanisms of dynamic nuclear polarisation (Overhauser effect) to the case of spin systems containing triplet states with S = 1 and nuclei with I = 1/2. In this mechanisms the optical electron polarisation (OEP) caused by symmetry selection rules for intersystem crossing to and from the magnetic triplet sublevels is assumed to be transferred to the nuclear magnetic substates by efficient hyperfine relaxation transitions.
The adiabatic fast passage is used to detect the nuclear polarisation. The advantages and conditions of this technique as compared to other nmr techniques are discussed.
ONP results at room temperature are given as a function of the external field H0, its orientation with respect to the crystalline axes, the intensity and frequency of the exciting light and the concentration and types of guest molecules. In phenazine crystals relative polarisation factors up to 50 are found with marked orientation dependencies even in fields as high as 11 kG. These results can be interpreted in principle in terms of the presented theory. However, in low fields (0 - 200 G) where ONP caused by hyperfine relaxation vanishes, large polarisations are found in doped crystals of fluorene and anthracene. The maximum absolute polarisation in fluorene doped with acridine is 3.6 · 10-4 at H0 = 80 G corresponding to a relative polarisation factor of ~ 104. The effect of doping is discussed.. Reference is made to a possible ONP mechanism 3 which is able to produce large nuclear polarisations at low fields
Untersuchungen zur Diffusion von Tritium in Übergangsmetallen
Authors: Sicking G. , Buchold H. 
Published: February 2015

Investigations of the diffusion of tritium in transition metals have been carried out by using "time-lag" methods.
The β-radiation, originating from tritium decay within a thin layer near the external surface of the metal, was taken as the signal to follow the change of tritium concentration with time in this layer. No passage of tritium atoms through the phase boundary is necessary for this method; the influence of energy barriers, which might retard this passage, can therefore not interfere.
Measurements with palladium at temperatures between 16.5 °C and 50 °C and vanishing hydrogen content in the Pd yielded:
D0
T = (10.5 ± 3.0) • 10-3 • exp{- (6350 ± 300)/RT} cm2 s-1, (R T in cal/mole).
The observed isotope effects in the diffusion of H, D and T in palladium are discussed. At 25 °C diffusion coefficients of tritium in Pd/Ag-alloys of different compositions (0 - 70 atom-% Ag) were determined. They first decrease slowly with rising silver content up to 30% and then drop sharply to very low values at higher Ag-contents.
Measurements with tantalum at 25 °C yielded: DT = (0.50 ±0.25) • 10-6 cm2 s-1
Driftgeschwindigkeit und Beweglichkeit von Elektronen in Silicium bei 4,2 °K in Abhängigkeit vom elektrischen Feld / Driftvelocity and Mobility of Electrons in Silicon at 4.2 °K in Dependence of Electric Field
Authors: Deimel P. 
Published: February 2015

Abstract
The pulse rise times of an n-type silicon surface barrier detector were measured at 4.2 °K. At this temperature the detector was fully depleted even at very low bias and the measured pulse rise times gave direct information about the driftvelocity and the mobility. Instead of E-0.5, an E-0.8 dependence of the mobility at moderate electric fields was found. At high electric fields agreement exists with theory.
Gleichzeitige Messung von Hyperfeinstruktur, Stark-Effekt und Zeeman-Effekt des 87RbF mit einer Molekülstrahl -Resonanzapparatur / Simultaneous Measurement of Hyperfine Structure, Stark-Effect and Zeeman-Effect of 87RbF with a Molecular Beam Resonance Apparatus
Authors: Heitbaum J. , Schönwasser R. 
Published: February 2015

Abstract
The electric and magnetic properties of the molecule 87RbF in the rotational state J = 1 and the vibrational states v = 0, 1 were studied by a molecular beam resonance apparatus. The rotational state (J, mJ) was separated by an electric quadrupole lense as A-field and focused to the detector by a similar lense as B-field. The vibrational states could be resolved by their different Stark-effect-energies. In the transition region homogeneous electric and magnetic fields were superimposed. The observed (ΔmJ = ±1) transitions were induced electrically.
The measured spectra permitted the calculation of the following molecular constants: the electric dipole moment µel, the rotational magnetic dipole moment µJ/J, the scalar and tensor nuclear dipole-dipole-interaction dS and dT the nuclear spin-rotational interactions cRb and cF , the nuclear quadrupole interaction e q QRb the nuclear magnetic moment µ(1 - σs)Rb, the anisotropy of the diamagnetic susceptibility (ξ⊥- ξ∥) the anisotropy of the diamagnetic shielding of the external field by the electrons at the position of the nuclei (σ⊥-σ∥]).
The results were (J = 1, v = 0) :
Electron-Spin-Resonance of Eu2+ in Ca-and Yb-Metal
Authors: Schmidt H. 
Published: February 2015

Abstract
ESR measurements of Eu2+ (concentration ≦ 1%) in Ca- and Yb-metal in the temperature range from 5 °K to 30 °K at microwave frequencies of 35 GHz and 9.6 GHz are reported. In Ca a “bottleneck” was observed, whereas in Y b the resonance condition is determined by the "dynamical effect". By adding Ca-impurities to Yb the influence of the dynamical effect was lowered. The measurements can be adequately described by the formulas of Hasegawa, yielding an exchange integral for Eu2+ in Yb of J =+ 0.09 eV.