bluuebunny/crossref_metadata_2025_split huggingface dataset:
Valence Force Constants and Normal Vibrations of Methanol
Authors: Timidei A. , Zerbi G. 
Published: February 2015

Abstract
The possibility of reproducing the normal vibrations of methanol, CH3OH, and its deutero-derivatives CH3OD, CD3OH, CD3OD using a valence force field has been critically analyzed. A 13 parameter valence force field has been determined by least square calculations. The meaning of the obtained numbers and their validity in molecular spectroscopy are discussed and compared with the information already available in the literature. It is concluded that the vibrational modes of this molecule are fairly well known within the harmonic approximation.
Decomposition of Equimolar NaBr-KBr Mixed Crystal
Authors: Ahtee M. , Inkinen O. , Koski H. , Pehkonen S. 
Published: February 2015

Abstract
The decomposition of equimolar NaBr-KBr mixed crystal has been studied within a temperature range of 115 to 251 °C. The measurements were made with an apparatus suitable for continuous recording of the changes in specimen capacitance. The results indicated that the decomposition takes place in three steps. A report is made on the decay constants, half-lives, and activation energies of the first two steps - the nucleation of a freshly prepared specimen, and the subsequent decomposition of the nucleated mixed crystal into components which are nearly pure. It was found that above 150 °C the rate of these processes is affected by a temperature-dependent effect of do-main formation. The experimental result for the activation energy associated with the processes, 0.84 ± 0.05 eV, compares favourably with the value derived from a simple diffusion model.
Notizen: On a New Theory of the Magnetization Curve of Plastically Deformed Nickel Single Crystals
Authors: Markert H. 
Published: February 2015

Abstract
A new theory of the magnetization process in plastically deformed nickel single crystals of single slip orientation is outlined. It is based on the interaction between the (101)-180°-domain walls and the three types of primary edge dis-location dipole and multipole arrangements dominating in stage I, in the transition region and in stage II of the stress-strain curve, respectively, i.e. the [121]-dipole bundles, the rope-like clusters of such bundles extended along [121], and the [121] -multipole walls, all having [T01]-Burgers-vectors. In increasing magnetic fields the primary edge dislocation arrangements are shown to be capable to glide to new ob-stacles under the pressure of the (101) -180°-domain walls which will follow them and whose segments at the same time start to vault themselves cylindrically or pillow-shapedly be-tween these dislocation barricades, finally overcoming them at the coercive force by Barkhausen jumps. In an earlier paper 1 first experimental results had been reported concerning the large decrease of num-ber and size of Barkhausen jumps observed on samples of plastically deformed nickel and on magnetite dur-ing simultaneously superposed intensive ultrasonic ir-radiation. To explain this unexpected effect in terms of domain wall motion, an attempt had been made to mo-dify the usual potential theory of the magnetization curve by introducting a new hypothetical magnetization process which should enable the domain walls also to move to some extent irreversibly and continuously but without Barkhausen jumps. In the meantime, the mentioned problems were sub-ject of a recently published extensive dissertation 2 which contains, in addition to a more detailed descrip-tion of the experiments and of the apparatus used, also the analysis of the main consequences of these experi-mental facts with respect to the usual potential theories of the magnetization curve of deformed nickel, showing the strong inconsistency between these theories on the one hand and the experimental results, reported in 1 and 2 , and certain other important empirical facts on the other. Last not least this dissertation contains a new consistent quantitative theory of the magnetization curve of plastically deformed nickel single crystals of single slip orientation. The aim of this note is to summarize in a qualitative manner the main statements of that new theory. Its basic assumptions which could be proved by quoting numerous experimental facts as well as by detailed quantitative estimations are the following ones:
Notizen: Microwave Spectrum of BaO
Authors: Hoeft J. , Lovas F.J. , Tiemann E. , Törring T. 
Published: February 2015

Abstract
Observation of the J=1 → 2 rotational transition of BaO in a microwave absorption spectrometer at 1700 °C is described. For 135BaO and 137BaO the nuclear electric quadrupole constants, e q0 Q, in the ground vibrational state are reported.
Notizen: The Ternary System K(CNS, HCOO, NO3)
Authors: Berchiesi Gianfrancesco , Cingolani Augusto , Leonesi Dante 
Published: February 2015

Abstract
As a part of our current researches, we report in the present paper on solid-liquid equilibria in the K (CNS, HCOO, N03) ternary system. Experimental
Notizen: Abschätzung der Frequenzen des IR-Spektrums des Schwefeldifluorids/Estimation of the IR-Frequencies of Sulphurdifluoride
Authors: Bliefert C. , Wanczek K.-P. 
Published: February 2015

Abstract
The theoretical IR-frequencies of sulphurdifluoride are computed from force constants, which are evaluated by means of molecules with S-F-bonds:
ν1 = 795 ± 10cm-1, ν2 = 430± 5cm-1, ν3= 830 ± 10cm-1.
Strain Effects on the Tunneling Levels of KCl: Li
Authors: Dischler B. 
Published: February 2015

Abstract
The effects of internal strains on the tunneling levels of KCl : Li are investigated quantitatively. The method, as developed in a preceding paper by TIMME, DISCHLER, and ESTLE1 , is further improved here. A reinterpretation is presented for two experimental results reported in the literature: the resonances in the phonon spectrometer curve and the specific heat (Schottky) anomaly. The agreement with these experiments and also with paraelectric resonance is good, if isotropic strains are assumed with an average energy of 20 GHz, corresponding to a stress of 30 ± 10 kp/cm2 . For the cube edge tunneling interaction a value of 10 GHz is derived.
The Vibrational Spectra of Strontium Chromate (SrCrO4) and Lead Chromate (PbCrO4)
Authors: Scheuermann W. , Ritter G.J. 
Published: February 2015

Abstract
The Raman spectra of the monoclinic compounds strontium Chromate, lead Chromate and of the mineral crocoite (PbCrO4) have been recorded at 300 °K and 77 °K. The spectrum of the orthorhombic modification of lead Chromate has also been recorded. The spectra of the monoclinic and of the orthorhombic PbCrO4 were found to be indistinguishable, whereas the spectra of the isomorphous monoclinic salts SrCrO4 and PbCrO4 are remarkably different. Inversion doubling was observed in SrCrO4 but less distinctly in monocrystalline crocoite.
Gestörte Diffusion von Argon in neutronenbestrahltem Kaliumchlorid
Authors: Müller M. , Felix F.W. 
Published: February 2015

Abstract
The influence of the neutron dose, the neutron spectrum and the sample preparation on Argon diffusion in neutron-irradiated KCl crystals was investigated. No effect of the concentration of the rare gas atoms nore of any other aliovalent atoms produced by nuclear reactions was observed. However radiation damage introduced by the fission neutrons seemed to influence the diffusion behavior. This radiation-damage could be annealed in the presence of thermal or slow epithermal neutrons. Lattice defects which are developed by cleaving of the crystals influenced the gas diffusion too.
Phase Diagram and Transport Properties of Cubic Lithium Sulphate with Small Quantities of Thulium Sulphate and Aluminium Sulphate
Authors: Bengtzelius Ante , Josefson Ann-Mari , Kvist Arnold , Schroeder Kjell 
Published: February 2015

Abstract
The phase diagram and electrical conductivity of cubic lithium sulphate with small quantities of thulium sulphate and aluminium sulphate have been measured. We have also measured the tracer diffusion coefficients of Tm3+ and Al3+ in pure cubic lithium sulphate. The diffusion coefficients of the trivalent ions are much lower than those of the univalent and divalent cations. The results indicate that the trivalent ions are trapped in the lattice.
The Problematic Charge-Transfer Triplet State of Electron-Donor-Acceptor-Complexes
Authors: Briegleb G. , Wolf D. 
Published: February 2015

Abstract
Iwata, Tanaka and Nagakura, and Hayashi, Iwata and Nagakura have observed in ethylether-isopentane solutions (1 : 1) at 77 °K, in the case of the complexes of tetracyanobenzene (TCNB) as the electron acceptor with the electron donors mesitylene (Me), durene (Du) and hexamethyl-benzene (HMB), an unstructured long-lived, long-wave emission band by exciting the complexes in the charge transfer (CT) band. They interpreted the 11, lw band as a CT-phosphorescence of a t t charge transfer triplet excited state | D + A" | . This would be of considerable theoretical interest and significance also for an interpretation of photochemical processes. In the present communication, we report results which lead us to a different interpretation of the 11, lw emission band under discussion. The emission spectra of the complexes of tetracyanobenzene (TCNB) with the electron donors toluene (To), p-xylene (Xy), mesitylene (Me), durene (Du) and hexamethylbenzene (HMB) were studied in glassy solutions in propylether at 100 °K. In the case of TCNB-To, -Xy, -Me and -Du, when the complexes were irradiated in the CT-band so that the complex components were not excited, we observed either the structured phosporescence band of TCNB which originates from a locally excited triplet state of complexed TCNB or, at large donor concentrations, the unstructured long-lived, long-wave emission band within the green spectral range. In the case of TCNB-HMB, only the 11, lw emission may be observed. The 11, lw unstructured emission superimposed on the structured TCNB phosphorescence may also be observed when TCNB, singly soluted in glassy solvents or crystallized, is irradiated in the 31,600 cm -1 (St S0) peak. Obviously, the 11, lw emission band may not be characteristic of the complexes of TCNB. Simultaneously with the 11, lw emission, a new molecular species X can be identified by a new absorption spectrum after irradiating either TCNB itself within the S0 —St 31,600 cm -1 peak or the TCNB-complexes within the CT-absorption band. X is formed by a reaction of the triplet ex-cited TCNB. The excitation in the long-wave absorption peak of X at about 21,000 — 22,000 cm -1 gives rise to an emission with a maximum in the same spectral range as the 11, lw emission band. Accordingly, we interpret the 11, lw emission as a delayed emission of X due to an energy transfer from the triplet excited TCNB.
The Use of the Modified Extended Hiickel Method in Molecular Dynamics
Authors: Yeranos Walter 
Published: February 2015

Abstract
Our previously proposed modification of Hoffmann's extended Hückel method is discussed, and its use in the determination of the dissociation energies of H3M-H type molecules where the H3M moiety is taken as a unit examined. The proposed technique is also used to study the angular dependence of the total potential energy of the previously studied molecules, as a consequence of which it is suggested that the proportionality constants (in this case the Fe 's) are atom-atom parameters, transferable from molecule to molecule. The latter concept is used in the theoretical determination of the geometries and energetics of CH3, SiH3, NH3, PH3,_as well as some of their ionic forms. Finally, as a result of our calculations, we suggest that CH3 is planar with a much flatter potential minimum than CH3.
Zum Vorkommen von Promethium in der Natur
Authors: Meier H. , Zimmerhackl E. , Albrecht W. , Bösche D. , Hecker W. , Menge P. , Unger E. , Zeitler G. 
Published: February 2015

Abstract
After a discussion of former publications on the problem of the existence of promethium in nature, studies o f our own on this problem are reported. In these researches, 200 kg of gadolinite were separated with regard to Pm by using one- and two-stage cation-exchange separations and nitrilotri-aceticacid for elution and Cu2+ as barrier-ion.
The experiments yielded a beta-activity in the mixture-fractions between Sm and Nd. Because of its chemical behaviour and its half-thickness of 4.4 mg/cm2 that corresponds with a β-maximum energy of 230 keV (147Pm: 223 keV), this beta activity could be identified as 147Pm. For the lanthanide oxides of gadolinite a 147Pm content of 7.3 · 10 - 17% could be deduced, which agrees well with the value of 4.5 · 10 - 17% found by Erämetsä in 20 t lanthanide oxides of 6000 t apatite. The possible origin o f the 147Pm-isotope we found in gadolinite is discussed (fallout, actinium anomaly, spontaneous fission of 238U, and others), and the reaction 11,Id 2,6a 14 6Nd (n, y)

is supposed to be the cause of the relatively short-lived isotope. The difference between the neutron flux (36 n/cm2 · min) that was deduced from the saturation activity of 147Pm, and the values of the neutron flux at the earth's surface or crust (0.001-0.24 n/cm2 · min) that up to now have been looked upon as probable by other authors, is also mentioned. Moreover, the question of the possible existence of a long-lived isomer of one of the known Pm-isotopes is rised.
Knight-Shift in kleinen Lithiumtröpfchen
Authors: Engelhardt A. , Sotier S. , Kalus J. 
Published: February 2015

Abstract
In der vorliegenden Arbeit wird untersucht, wie sich die Knight-Shift von kleinen Lithiumtröpfchen in LiF-Kristallen mit der Größe der Tröpfchen verändert; die Tröpfdien wur-den durch Neutronenbestrahlung erzeugt, ihre Größe konnte durch Tempern verändert werden.
On the Field Emission from Ni, Gd, and EuS Evaporated on to Tungsten
Authors: Eckstein W. , Georg K.F. , Heiland W. , Kirschner J. , Müller N. 
Published: February 2015

Abstract
Tungsten tips coated with Ni, Gd and EuS are studied in a field electron microscope. Reproducible patterns are observed. The Gd-patterns show epitaxy with the W-substrate. With tempered tips the work functions are: Ni 5.1 ± 0.3 eV, Gd 3.2 ± 0.3 e V and EuS 3.1 ± 0.3eV.
For the production of polarized electrons by field emission from materials with spin polarized bandstructure 1 - 4 the field emission from Gd, Ni and EuS is of interest.
Exakte Dämpfungskennwerte bei linearen Schwingungen
Authors: Troost A. , Betten J. 
Published: February 2015

Abstract
In der vorliegenden Untersuchung werden Dämpfungskennwerte allgemein formuliert. Als Beispiele sind Kennwerte freier und erzwungener gedämpfter Schwingungen aufgeführt. Die erörterten Abweichungen der meistens benutzten Umrechnungsbeziehungen von den strengen Gleichungen erklären zwanglos einander widersprechende Angaben im Schrifttum.
Stoichiometric FeO as Metastable Intermediate of the Decomposition of Wustite at 225 °C
Authors: Hentschel Bernhard 
Published: February 2015

Abstract
If a wustite sample prepared above 1000 °C is annealed at 225 °C stoichiometric FeO occurs as a metastable decomposition intermediate, as has been demonstrated röntgenographically and by means of the Mössbauer-effect.
Anwendung der Methode der Korrelationsfunktion auf die Berechnung der Richtungsabhängigkeit von Hc2 im kubischen Einkristall
Authors: Harms Klaus-Dieter 
Published: February 2015

Abstract
The upper critical magnetic field for a monocrystalline superconductor with cubic symmetry is calculated using the Method of the Correlation Function. The symmetry of the system leads to an eigenvalue equation which is solved with perturbation-theoretic methods. The upper critical field is calculated for dirty superconductors in the lowest order for which anisotropy is present. For clean superconductors, a higher order is calculated. Some results are critically compared with those in a paper by HOHENBERG and WERTHAMER.
Oberflächenspannung und Thermodynamik des perfekten Gases
Authors: Hilf Eberhard 
Published: February 2015

Abstract
A thermodynamic system of N Fermions or Bosons, bound by an external potential but with almost no additional contribution of the interaction energy between the particles to the binding of the system is called a bound perfect quantum gas. Its single particle energy level density ρ (ε) depends on the properties of the external potential. This is chosen to be zero inside and infinite outside a given arbitrary simple connected closed shape. Within the leptodermous assumption A N1/3 ≫ 1 then ρ (ε) can be written explicitly as a sum of three terms which are proportional to the volume, surface, curvature tension. Its thermodynamics is developed: 1) one thermodynamic variable can be eliminated, reducing the phase space dimensions; 2) the Gibbs - Duhem relation is disfigured only by surface - and curvature terms, stating that the system is still makroscopically homogenious except in the surface area, where e.g. the particle density falls down to zero smoothly; 3) the Landsberg-definition p · V = ⅔ U still holds, confirming that our microscopically defined system is macroscopically a perfect gas in the sense of Landsberg, despite the surface phenomena. In the appendix the advantages of an operatorlike shortwriting of the partial derivative notation are demonstrated.
Ein einfaches statistisches Modell für Transportvorgänge mit beschränkter Ausbreitungsgeschwindigkeit. I
Authors: Keller J.U. 
Published: February 2015

Abstract
A simple statistical model for transport-processes in material systems like heat conduction, diffusion and Rrownian motion is given. The model consists of a one-dimensional unrestricted random walk process. The jump-probabilities of the random-walk-particle generally depend on the history of the particle. The transport equations following from this model describe, contrary to the equations given by Fick, Fourier, Smoluchowski and Fokker-Planck always transport-processes with bounded velocity of propagation.
Ein einfaches statistisches Modell für Transportvorgänge mit beschränkter Ausbreitungsgeschwindigkeit. II
Authors: Keller J.U. 
Published: February 2015

Abstract
In a paper 1 published recently a one-dimensional random walk-model for transport-processes with bounded velocity of propagation like heat conduction, diffusion and Brownian-motion has been given. Now this model is generalized to processes in 3 dimensions. We consider the transport process as a random-walk process in a primitive cubic lattice without boundaries and without external forces. The jump-probabilities of the random-walk-particle generally depend on the history of the particle. The resulting transport-equation contains terms which are due to the structure of the lattice not invariant under rotation. Further on this equation always describes transport-processes with bounded velocity of propagation.
Schwingungsspektren und Kraftkonstanten einiger Tertiärbutylacetylene
Authors: Hüttner W. , Zeil W. 
Published: February 2015

Abstract
A normal co-ordinate analysis of the vibrational spectra of the (CH3)3C-C = C-H, - D, -Cl, -Br and -J compounds has been carried out, and force constants of three slightly different simplified valence force fields have been obtained. Both the iteration procedure described in the preceding paper, and a well-known least-squares technique were used in the computations. The first method proved successful for all species and all force fields. The least-squares method yielded converging results in the case of tertiary butyl acetylene, when the two isotopic frequency sets were refined simultaneously and when a sufficient amount of constraint was introduced into the force field. The force constants belonging to the same force field as obtained by the two independent methods are in good agreement. The valence constants of the acetylenic chain seem to reveal some expected distinctions in the bond properties of the pure acetylene and the halogenated compounds.
Messungen der radialen Verteilung der elektrischen Feldstärke im Wasserstofflichtbogen mit axialem Magnetfeld
Authors: Schwenn R. 
Published: February 2015

Abstract
In a stationary hydrogen arc with axial magnetic field the radial distribution of the axial electric field Ez was measured by shooting a double potential probe across the arc. It was found that Ez strongly decreases outside the magnetic flux tube defined by the cathode radius and tends to zero. The measured distribution of Ez agrees qualitatively with computations allowing for the observed rotation profile. In a very fast rotating arc with a hollow anode Ez was found to vanish not only outwards, but also towards the axis, as predicted by the theory.
Radiales Druckprofil in einem magnetoplasmadynamischen Wasserstoff-Lichtbogen
Authors: Bohn W. L. , Mccann T. E. 
Published: February 2015

Abstract
Within the framework of the five-moments approximation the radial pressure profile of an MPD-arc is calculated as a function of the ambient pressure and the superimposed magnetic field. In addition to the well known pressure increase due to ambipolar diffusion, the typical axi-symmetric MPD geometry provides further pressure increase or decrease by the interaction of current density (Hall-effect) or mass flow with the magnetic field. Characteristic pressure profiles for assumed current and flow fields and for various superimposed magnetic field strengths are shown in numerous diagrams and are discussed by use of the generalized Ohm's law. A significant pressure decrease due [to mass entrainment becomes evident. Deviations from LTE are considered in the frozen flow approximation. The theoretically predicted pressure decrease in the axial region of the plasma flow of an MPD-arc subjected to mass entrainment agrees qualitatively with experimental results.
Bestimmung der Ionendichte aus der Stark- Verbreiterung der Hβ-Linie bei elektrischen Entladungen in H2-cluster-Strahlen
Authors: Klingelhöfer R. , Moser H. , Röhl H. 
Published: February 2015

Abstract
A transient plasma column is produced by discharging a 0.1 μF-capacitor at 20 kV along a beam of hydrogen clusters. The time dependance of the ion density is obtained from Stark broadening measurements of Hβ (4861 Å). A maximum density of 6.6 × 1016 ions/cm3 is achieved, the initial density of the neutrals in the beam being 8.5 × 1017 H2 molecules/cm3. The background number density in the surrounding vacuum amounts to about 7 × 1010 molecules/cm3.
Atom Transport Under Varying Pressure * *
Authors: lazarus D , Yoon D. N. , Jeffery R. N. 
Published: February 2015

Abstract
Study of the effect of hydrostatic pressure on the rate of diffusion-limited processes gives in­ formation regarding the intrinsic volume changes associated with formation and motion of defects. While there are basic problems associated with interpretation of the motional volume, such effects may be measured directly in some cases and subtracted to give unambiguous results for the defect formation volume. Experimentally, precise measurement of specimen temperature within a high-pressure environment poses the most severe practical constraint. Results are given for measurements to pressures of 7 kilobars of ionic conductivity in a series of pure and doped alkali halides: NaCl, KCl, NaBr, and KBr, all of which are predominantly cationic vacancy conductors. The activation volumes are found to be pressure dependent in the intrinsic regions. In all cases the Schottky pair vacancy formation volume is found to be larger than the molar volume, the ratio being largest for NaCl and smallest for KBr. Results are also given for the total activation volume for diffusion of Ti44 in beta-Ti, a case of "anomalous" bulk diffusion. The tracer penetration plots do not follow a perfect gaussian profile. However, if the penetration plots are fit to a single gaussian, the activation volume derived is consistent with that expected for a vacancy mechansm in bcc metals