bluuebunny/crossref_metadata_2025 huggingface dataset:
The Imposition of Empirical Acceptability Conditions on Sequences of Single Measurements
Authors: Benioff Paul A.
Published: February 2015

Here, some difficulties resulting from the application of any empirical acceptability conditions on sequences of single measurements are investigated. In particular, the often used acceptability requirement that each single measurement be made under the "same conditions" is discussed. In quantum mechanics, this means that each single measurement is made of the same physical quantity on a system in a ensemble of identically prepared systems.

One of the resultant difficulties is that such an application leads to an infinite regression of sequences of single measurements. That is, it does not account for the fact that an observer must start the process of measurement or knowledge acquisition. Furthermore, it is seen that there are some basic sequences of single measurements for which an observer can not possibly know at the outset that the "same condition" requirements are satisfied. These include those measurements by which the homogeneity of space-time is tested.

The possible relevance of these difficulties to physics is shown by first considering two possi­bilities of avoiding these difficulties. One is that the "same condition" requirements can be given the weaker interpretation that there be no physical principle forbidding an observer from knowing in terms of limit empirical means, that they are satisfied at the outset of any sequence. This gets rid of the infinite regression problem as it does not mean that an observer must know in fact that these requirements are satisfied.

The other possibility is that if physics does not forbid one in principle from measuring an expectation value in an arbitrarily small time interval then both the basic sequence as well as those by which one knows the "same" requirements are satisfied can be relegated to arbitrarily small time intervals. As far as physics is concerned, then the epistemological difficulties while existing in these small intervals, do not exist for other times, or almost all time.

It is then shown that quantum mechanics, as distinct from classical mechanics, and the special relativity require that an infinite time interval is necessary to measure, as a limit mean, any expectation value. Thus physics denies both the above possibilities as it forbids an observer from knowing even in principle, by any finite time that the "same" requirements are satisfied. Also, physics forbids the relegation of the epistemological problems to arbitrarily small time intervals.
Charakteristische Kaustikverläufe in austretenden Strahlenbündeln von Elektronenkanonen *' *
Authors: Hanszen Karl-Joseph , Lauer Rolf
Published: February 2015

Die Systematik der recht komplizierten Kaustikverläufe im austretenden Strahlenbündel einer Elektronenkanone kann in einfacher Weise auf Abweichungen des kathodennahen Feldes von der Zentralsymmetrie und auf Bildfehler des übrigen, als Immersionslinse wirkenden Beschleunigungsfeldes zurückgeführt werden. Die Ergebnisse stehen mit dem Experiment in Einklang.
On the Quantum Theory of the Anharmonic Oscillator in Functional Space
Authors: Stumpf H.
Published: February 2015

Dynamics of quantum field theory can be formulated by functional equations. For strong inter­action nonperturbative solutions of these functional equations are required. For the investigation of solution procedures the model of an anharmonic oscillator is used, because of its structural equi­valence with dressed one- and two-particel states of field theory. To perform a variational solution procedure a scalar product for the state functionals is introduced and its existence is proven. The scalar product definition admits a mapping of the physical Hilbert space on the functional space. Therefore a “functional” quantum theory seems to be possible. The whole procedure can be transferred to relativistic invariant field theories, provided these theories are regularized to give finite results at all.
Phase Effects in the Nonlinear Interaction of “Negative”-Energy Waves
Authors: Engelmann F. , Wilhelmsson H.
Published: February 2015

Nonlinear interaction of “negative”-energy waves is studied assuming well-defined phases and perfect matching conditions. The results are compared with those of the random-phase approach, and significant differences in the dynamics due to phase effects are pointed out.
Die Energieverteilung im Strahlenbündel einer Elektronenkanone mit einkristalliner Kugelkathode. A. Einflüsse im Beschleunigungsraum
Authors: Hanszen K.-J. , Lauer R.
Published: February 2015

Durch Anwendung einer dicht hinter der Anode liegenden Blende mit kleiner Bohrung können die bereits innerhalb der Elektronenkanone auftretenden Einwirkungen auf die Energieverteilung in den durchgelassenen Teilstrahlbündeln ermittelt werden. Es kann zwischen Einflüssen der Austrittsarbeit, der Raumladungswolke und der Strahlüberschneidungen unterschieden werden; diese Erscheinungen bewirken leicht überschaubare Veränderungen der mittleren Energie, der Halbwertsbreite und der Verteilungsform. Besonders schmale Energie verteilungen treten nahe beim Sperrpunkt und im sogenannten „zweiten Hohlstrahlgebiet“ auf.
Relative Contributions of Odd Vibrations to the Intensity of the First Band of Co(NH3)63+
Authors: Yeranos W.A. , Joncich M. J. , Hasman D. A.
Published: February 2015

Without actually evaluating the integrals involved, an experimental technique and a mode of analysis have been developed to quantitatively verify van Vleck’s theory of vibronic interactions. The success of the analysis suggests that errors introduced by the computational approximations far outweight those introduced by the partial breakdown of the assumptions upon which the theory is constructed. Specifically, the vibronic transition at 21 200 cm-1 of Co(NH3)63+ has been used to discuss the techniques developed. Furthermore, it has been established that at all temperatures from 293 °K down to 83 °K the ν̃6 vibrational mode of the MX6 entity is primarily responsible (60%) for the admixture of odd parity in the ground and the first excited states of Co (NH3) 6
3+.
Die anisotrope Hyperfeinaufspaltung der Elektronenspinresonanz durch eine rotierende H 3-Gruppe
Authors: Reitböck H.
Published: February 2015

The anisotropic splitting of the electron spin resonance, due to the interaction between an un­paired p-electron and a rotation H3-group is calculated. The results are compared with experimen­tal data from the H3N+‒ĊH‒COO‒.Radical in irradiated glycine.
Die Beeinflussung des Ionisationsgrades durch Diffusions­ und Massenströme im Plasma
Authors: Bergstedt K.
Published: February 2015

A stationary, magnetically stabilized helium arc plasma is taken as an example to show that ionization degrees in such plasmas with large electron temperature and electron density gradients may not be calculated from static ionization relations valid for homogeneous plasmas (e. g. the Saha equation). Instead, ionization degrees in inhomogeneous plasmas must be determined from continuity equations of the form div (nΖυΖ)nΖ = JΖ-1 nΖ-1 -RΖnΖ nz where JΖ-1 and nΖ-1 are the ionization rate and the density of the Z -1 times charged ions, and RΖ , nΖ and υΖ are the recombination rate, the density and the centre-of-mass velocity of the Z times charged ions. Static ionization formulae may not be applied to inhomogeneous plasmas because the finite relaxation times for the attainment of static ionization equilibria result in these ionization equilibria being displaced by the motion of the ions parallel to the direction of electron temperature and density gradients.

This is proved by means of two independent operations: firstly, the velocities of the helium ions, these being governed primarily by ambipolar diffusion, are calculated with the spectroscopically measured state variables from the momentum equations of the plasma; secondly, the velocities of the doubly charged ions are determined by integrating the continuity equation for these ions, use again being made of the measured state variables and of the ionization and recombination rates J1 and R2 of the helium ions that were calculated for this special plasma. The agreement between the independently obtained velocity values proves that the degree of ionization of the helium ions in this inhomogeneous plasma is described not by a static ionization formula, but by the continuity equations for these ions.

Furthermore, it is shown that the ionization "equilibria" between singly charged and neutral helium particles and between three times (CIV) and four times (CY) charged carbon particles are not determined by means of static ionization formulae either.

The influence of this hitherto disregarded effect on the spectroscopic determination of the electron temperature in the plasma discussed is illustrated in a diagram.
Solution of the Dirac Equation for the Rectilinear Periodic Motion of an Electron
Authors: Jannussis A. D.
Published: February 2015

In this paper the Dirac equation for a rectilinear onedimensional periodic potential is treated. It is shown that the energy eigenvalues are periodic functions of the wave number Kϰ and the continuous spectrum is split into energy bands. The end points of the energy bands are the points where the Bragg reflection takes place.

These results are obtained by perturbation theory, as well as by the method of determinants, since the resulting eigenvalue equation has the form of a determinant which is similar to the Hill determinant.
Zufallswege und Reaktionen atomarer Gitterfehler in Modellkristallen
Authors: Mehrer Helmut
Published: February 2015

Random walks and reactions of point defects in face-centered cubic lattices have been simulated by means of a Monte-Carlo method described in the preceding paper (I) . In this paper the method is applied to the recombination of vacancies and interstitials. Equal or different numbers as well as random or correlated initial distribution of vacancies and interstitials are considered. The inter­ action between the defects is taken into account by a model for the pair volume surrounding a vacancy.
Zum dielektrischen Verhalten von Triglyzinsulfat im Bereich von 0,5 bis 4,5 GHz
Authors: Luther G. , Müser H. E.
Published: February 2015

The complex permittivity of Triglycine Sulphate is measured from 0.5 to 4.5 kMc/s as a function of temperature. A dispersion is observed which is of a simple Debye relaxation rather than a resonance type. Thus the form of the relaxation differs from the Gaussian distribution of relaxation times found by HILL and ICHIKI. The relaxation frequency increases linearly with temperature above the Curie point. Above 0.5 kMc/s the real part of the permittivity undergoes a more and more pronounced minimum at the Curie point.
Statistical Foundations of Thermodynamics II. Equivalence Problem. Stability Conditions
Authors: Still E. , Haubold K. , Münster A.
Published: February 2015

On the basis of the results obtained in a previous paper it is shown that in the thermodynamic limit the analogues of the Massieu-Plandc functions are linked with each other by means of the Legendre transformation. The existence of the limiting function φk
(∞) implies the existence of the limiting function φl
(∞) (l<k) under the same assumptions. Passage to the limit and derivation with respect to all independent variables commute. A statistical derivation of the thermodynamic stability condition in its most general form is given which leads naturally to a statistical interpretation of the concept of thermodynamic stability.
Untersuchungen an Thermoketten
Authors: Haase R . , Richter J.
Published: February 2015

Es werden Thermoketten betrachtet, die zwei Elektrolyte mit insgesamt drei Ionenarten in ge­schmolzenem Zustand enthalten. Mit Hilfe der Methoden der Thermodynamik der irreversiblen Pro­zesse lassen sich die allgemeinen Ausdrücke für den Anfangswert und den Endwert der Thermokraft einer solchen Thermokette gewinnen. Die aus den Messungen bestimmbaren charakteristischen Größen sind die beiden Überführungsentropien der den Elektrolyten nicht gemeinsamen Ionenarten, gemessen relativ zur gemeinsamen Ionensorte. Die entsprechenden Formeln für Thermoketten mit reinen flüssigen Elektrolyten lassen sich als Grenzfälle ableiten. Messungen von Sundheim und Kellner an Thermoketten, kombiniert mit anderen Literaturdaten, ergeben die Überführungsentropien der Natrium-und Silberionen für die binäre Schmelze NaNO3+ AgNO3 in Abhängigkeit von der Zusammensetzung bei 310 °C. Anhangweise werden die Konsequenzen eines einfachen Ansatzes für die Uberführungszahlen, wie er für NaNO3 + AgNO3 zu gelten scheint, besprochen. Dabei wer­ den auch Konzentrationsketten behandelt.
Begründung der Lorentz-Gruppe allein mit Symmetrie-und Relativitäts-Annahmen
Authors: Süssmann G.
Published: February 2015

Aus dem Relativitätsprinzip folgt ohne Verwendung des empirischen Prinzips von der Konstanz der Lichtgeschwindigkeit, daß die Lorentz-Transformation die einzig denkbare Alternative zur (raumzeitlich asymmetrischen) Galilei-Transformation ist.
Arc Phenomena and Gasdynamic Effects due to Interaction of Shock Waves with Magnetic Fields II
Authors: Klingenberg H.
Published: February 2015

In these experiments continuing the work on interaction published in 1, the magnetic field, i.e. the retarding force, has been increased. This produces reflected shocks that leave the inter­action region, but the steady state could not be achieved.
Zur Struktur der Graphit-Eisen(III)-chlorid-Einlagerungsverbindungen
Authors: Knappwost A. , Grigutsch F. D.
Published: February 2015

Die allgemein übliche Charakterisierung gewaschener Graphit-Eisen(III)-chlorid-Einlagerungsverbindungen nach ihrem Eisenchloridgehalt allein ist unzureichend, weil die aus gesättigten Verbindungen eluierte Eisenchloridmenge eine Funktion der Teilchengröße der Graphitkristalle ist. Diese Ergebnisse stützen die zuerst von Rüdorff und Landel beschriebenen Anschauungen, daß nach Eluieren des Eisenchlorids in den Randzonen die Graphitstruktur zurückgebildet wird. Dadurch wird das Kristallinnere vor einem weiteren Lösungsmittelangriff bewahrt, und die Struktur der ersten Verbindungsstufe bleibt dort erhalten..

Der bisweilen beschriebene Unterschied zwischen Natur- und Synthesegraphit im Eisenchlorid-Maximalgehalt gewaschener Einlagerungsverbindungen läßt sich ebenfalls durch die Teilchengrößenfunktion erklären und braucht nicht auf die unterschiedliche Herkunft der Graphite zurückgeführt zu werden.

In dem vom Lösungsmittel nicht angegriffenen Verbindungskern sind ca. 40% der verfügbaren Schichtfläche nicht mit Eisenchlorid besetzt. Dichtemessungen und Röntgen-Untersuchungen ergeben, daß die Kohlenstoffschichten in diesen Bereichen nicht aufgeweitet sind, sondern den gleichen Schichtabstand wie der reine Graphit aufweisen. Aus der Linienschärfe der Röntgenreflexe folgt, daß die Ausdehnung der kohärenten Bereiche mit Graphitstruktur in c-Richtung im Mittel über 800 Å beträgt. Der für Graphit typische anomale Diamagnetismus tritt bei den Einlagerungsverbindungen trotz dieses Graphitanteils nicht auf.
Bestimmung der Halbwertszeit von 210Pb
Authors: Höhndorf A.
Published: February 2015

The half-life of 210Pb has been calculated from measurements of the specific activity and the 210Pb-concentration of a 210Pb-solution. The specific 210Pb-activity was determined by measuring the daughter product 210Po using an α-spectrometric isotope dilution method with 208Po as tracer. The 210Pb-concentration was measured by mass-spectrometric isotope dilution analysis. A half-life of 22.26 ± 0.22 ( = 2 σ) years has been obtained.
Negative magnetische Widerstandsänderung von ZnSb
Authors: Peters F. , Schneider G.
Published: February 2015

ZnSb zeigt wie einige andere Halbleiter bei tiefen Temperaturen die eigenartige Erscheinung einer negativen magnetischen Widerstandsänderung, d.h. eine Abnahme des elektrischen Widerstandes im Magnetfeld. Die Größe dieses Effektes wurde in Abhängigkeit vom Magnetfeld H und von der Ladungsträgerkonzentration p untersucht. Für das Auftreten der Erscheinung können Grenzen in bezug auf p und H angegeben werden. Die Messungen an einkristallinem und polykristallinem Material zeigen unterschiedliche Resultate. Die Ergebnisse werden vor allem in bezug auf verschiedene Komponentenzerlegung in positive und negative Anteile der Widerstandsänderung

diskutiert.
Calculation of the Centrifugal Distortion Constants Using Dependent Internal Coordinates, Numerical Example Cyclopentene
Authors: Petzuch M.
Published: February 2015

A formula is derived for the calculation of the centrifugal distortion constants ταβγδ in the case where the vibration problem is solved by using dependent internal symmetry coordinates. We have calculated the τ’s and the D's with this new formula for a model of cyclopentene with a planar carbon ring (Point group C2v).

The τ-values calculated are (in units 1085 sec2 (gem2)-3):

τxxxx = - 5.27, Txxyy = 1.48, τxxzz = - 0.96,

τyyyy = - 5.52, Tyyzz = - 1.22, Tzzzz = - 0.63,

τxyxy = - 2.85, Tyzyz - 0.07, Tzxzx = - 0.07.

The D's calculated are (in units 10-8 cm-1):

DJ = 7.9, DK = 5.1, DJK = - 12.1.

The values for DJ and for DJK are within the accuracy of the published experimental values.

Thus, cyclopentene is the first ring molecule, the centrifugal distortion constants of which could be calculated.
Notizen:Eine Gasmischung aus Argon und Stickstoff als Füllung für α-Proportionalzählrohre
Authors: Heye Dietrich
Published: February 2015

A counting gas has been tested which can be used for α-proportional counting at high temperatures (700 °C). A mixture of 13 parts Ar and 1 part N2, is stable at a pressure of 700 mm Hg. The counter has a plateau of more than 100 Volts with low slope. The stability which has been tested for a period of 55 hours and 108 counted pulses proved to be satisfactory.
Notizen:Estimation of Electric Polarizabilities of Organic π-Electron Systems from Kerr Effect Measurements
Authors: Schweig A.
Published: February 2015

A method to estimate the principal polarizabilities of π-electron clouds embedded in a continuous uniform medium of dielectric constant ε0 = 2 is described and applied to deter­mine these polarizabilities in the case of aromatic hydro­carbons.
Extremaleigenschaften von Kraftkonstanten
Authors: Über Iii , Strey G.
Published: February 2015

Els wird der Bcwcis geführt, daß das Modcll dor progressiven Starrheit von Toifungton mit sukzessive eingeführten Minimalforderungen an die diagonalen Elemente der Matrix der Kraftkonstanten verknüpft ist.
Das Mikrowellenrotationsspektrum des PbTe
Authors: Tiemann E. , Hoeft J. , Schenk B.
Published: February 2015

Im Frequenzbereich 11 - 15 GHz wurden bei Temperaturen um 680 °C die Rotationsübergänge J = 5 → 6 und J = 7 → 8 von 16 isotopen Molekeln des PbTe gemessen. Es werden Rotationskon­stanten, Kernabstände und Koeffizienten der Potentialfunktion nach Morse sowie Massenverhält­nisse von Blei- und Tellurisotopen mitgeteilt.
Abklingzeitmessungen an Pseudoisocyanindiäthylchlorid mit einem Phasenfluorometer mit 200 MHz-Lichtmodulation
Authors: Michelbacher E.
Published: February 2015

The decay time of pseudo-isocyanine (2,2 nsec at room temperature) has been measured by a phase fluorometer of 200 Me modulation frequency and its temperature dependence with respect to self absorption has been investigated. This allows to calculate the molecular decay time (1,7 nsec) and the number of molecules, which form the fluorescent polymer of the dye. Moreover the decay times of some p-oligophenylenes and the quenching effekt of nitrobencene on POPOP (1,82 nsec) have been measured.
Zur anodischen Bildung von Silberoxiden
Authors: Gossner K. , Eftychiadis Th. , Körner D.
Published: February 2015

Die anodische Oxydation von Silber wurde in alkalischem Milieu (0,01-n. NaOH) galvanostatisch und potentiostatisch verfolgt, und parallel dazu wurde die Bildung der Oxidphasen durch Elektronen­beugung untersucht und den Ladekurven zugeordnet. Die Ladekurven zeigen bei galvanostatischer Versuchsführung unabhängig von der vorgegebenen Stromdichte einen gleichartigen Verlauf; bei potentiostatischer Versuchsführung verlaufen sie je nach Polarisationsbereich verschieden. Sowohl bei galvanostatischer als auch bei potentiostatischer Oxydation wird stets die Bildungsreihenfolge Ag → Ag2O → AgOx → AgO gefunden. Im Bereich der beginnenden Sauerstoffentwicklung tritt manchmal Ag2O3 auf.
Zur anodischen Bildung von Silberoxiden
Authors: Gossner K. , Eftychiadis Th. , Körner D.
Published: February 2015

Bei der Untersuchung anodisch oxydierter Silberelektroden durch Elektronenbeugung werden die folgenden Oxide gefunden: das kubische Ag2O, das "AgOx" mit kubisch-flächenzentriertem Ag-Teil-gitter und das monokline AgO. Auf einigen Beugungsaufnahmen wurde das kubische Ag2O3 identi­ fiziert. Die jeweilige Oxidschicht auf den Silberelektroden erweist sich bei Abtragung durch Ionen­ ätzung als einheitlich. Die Zuordnung der einzelnen Oxidphasen zu den entsprechenden Bereichen der galvanostatischen Ladekurve ermöglicht eine Deutung des zeitlichen Potentialverlaufs während der Oxydation. Der je nach angelegter Polarisation unterschiedliche Verlauf der potentiostatischen Ladekurven läßt Rückschlüsse auf den jeweils vorherrschenden Oxydationsmedianismus zu.
The Phase Diagram of the System Li2SO4 — K2SO4 from Differential Thermal Analysis
Authors: Schroederand Kjell , Kvist Arnold
Published: February 2015

The phase diagram of Li2SO4-K2SO4 has been determined by differential thermal analysis. By making use of ail improved method, the sensitivity of the measurements has been increased and we have found a number of new transitions, especially in the lithium sulphate rich region. We have also detected a new transition in LiKSO4 at 672 °C. The new transitions have lead to an unusually complicated phase diagram compared with other sulphates. Some of the results have been checked bv measuring the electrical conductivities of the phases.

XFA (9014)
The Die Zustandsgleichung isotoper Äthylene
Authors: Dorfmüller Th. , Göpel W.
Published: February 2015

The second virial coefficients of C2H4 and C.D4 have been measured at 236.04 K. The experimental isotope etlect of 1.07% can he separated into one contribution from a trans­lational quantum effect and one contribution which is due to the different molar volumes of the isotopes. In this tempera­ture region the isotope effect is shown to be mainly a volume effect. This explanation is confirmed by results from molar volume measurements of the liquid isotopes.
Das Fluoreszenzspektrum von Anthracen-Kristallen
Authors: Glöckner E. , Wolf H. C.
Published: February 2015

The fluorescence spectrum of extremely purified and good anthracene crystals has been re­measured. It is compared with the exciton band structure as calculated by Davydov and Sheka. The origin of the intrinsic fluorescence is at 25 097 cm-1. This is the lower edge of the exciton band with k ≠ 0. Therefore this 0.0-transition is forbidden. The allowed 0.0.transition of the lower Davydov component of the exciton band is observed at 25 298 cm-1 with very low intensity. This is the position of the very short living state k = Q (Q=photon wave vector) in the exciton band. Further observations concerning the structure and temperature dependent width of emission lines, the nature of exciton-phonon and exciton-vibron coupling and the large band width in absorption are also in good agreement with the calculated band structure.

The polarization ratio of the strongest vibronic transitions is 7.5 ± 1 good agreement with the oriented gas model. The spectral region near the forbidden 0.0-transition is completely 6-polarized. Effects of defects in the spectrum (series of lines due to impurities and X-traps, continuous back­ground) were widely eliminated. They are discussed here only as far as necessary for a better understanding of the unperturbed crystal spectrum.

In an appendix a list of 154 fluorescence lines is given.
Optische Spin-Polarisation im Triplett-Zustand von Naphthalin
Authors: Schwöhrer M. , Slxl H.
Published: February 2015

Naphthalene, which is excited into the lowest triplet state by unpolarized UV-Iight shows a strong deviation from the Boltzman distribution within the three magnetic sublevels, which is ob­served by ESR. We call this deviation optical spin polarization. In the mixed crystal C10D8
: 0.2% C10H8 , where the undeuterated Naphthalene acts as trap at 4.2 °K, the optical spin polarization exceeds the thermal spin polarization such that a steady state inversion between two of the mag­netic sublevels appears. This results in an emissive ESR-transition (stimulated emission of micro- waves). The time dependence of the spin polarization after switching on or off the UV-light is described by a superposition of two exponential functions with different rate constants. - The optical spin polarization is due to spin selection rules for the intersystem crossing process (ISC). These involve primarily the molecular symmetry. - The experimental results of the present paper are these selection rules for the pumping processes: The metastable triplet state is populated via the spin component τx.The depopulation rate constants of the three spin components τx, τv and τz are kx = 0.65 sec-1, ky=0.4 sec-1 and kz=O.15 sec-1 .The spin lattice relaxation probabilities are of the order of 1 sec-1. The latter are dependent on the direction of the magnetic field and on the concentration of the populated triplet states. - These results are compared with a theory of ISC.
Functional Quantum Theory of Scattering Processes I
Authors: Stumpf H.
Published: February 2015

Dynamics of quantum field theory can be formulated by functional equations. To develop a com­plete functional quantum theory one has to describe the physical information by functional opera­tions. One of the most important physical information of elementary particle physics is the S-matrix. To derive a functional expression for this quantity the potential scattering model is studied. A func­tional S-matrix is defined and its equivalence with the ordinary S-matrix definition in physical Hilbert space is proven. Also a calculational method for scattering functionals is proposed. In the appendices technical details are discussed.
Messungen des Anlagerungskoeffizienten von Elektronen in Sauerstoff
Authors: Grünberg R.
Published: February 2015

The attachment coefficient η for the formation of negative ions in low energy electron swarms was measured over an E/p-range of 0.1 ... 30 V/Torr cm by a new and accurate method. Thus earlier measurements up to 54 Torr of other authors could be extended to 880 Torr.

The shape of the minimum in the η/p-curves between the three-body process (e+2O2 → O2
- + O2) and the dissociative process (e + O2 → O- + O) and its shift to higher E/p with increasing pressure was measured. Behind the minimum a maximum at E/p = 14 was found. Between the minimum and this maximum the dissociative process is predominant but the three-body process is still of influence. For E/p > 14 the η/p-values are slowly decreasing with increasing E/p.

For the higher pressures above 44 Torr deviations from the relation η proportional to p2 were found for the three-body process. These deviations are discussed.
Absorptionsspektroskopie an resonanzverbreiterten Atomlinien zur Dichtemessung in Düsenstrahlen
Authors: Brunner W.
Published: February 2015

Die Absorptionsspektroskopie an resonanzverbreiterten Atomlinien wird als einfaches und genaues Meßverfahren beschrieben, das vor allem für Untersuchungen an Zweiphasengemischen geeignet ist, bei denen ein Anteil aus Metalldampf besteht. Die zum Verständnis notwendige Theorie wird kurz skizziert und ein Anwendungsbeispiel beschrieben. Dabei handelt es sich um eine Zweiphasenexpansion ins Vakuum, die mit einer Metallverdampfung verbunden ist.
Kernrelaxation und Quanteneffekte bei der Methylgruppenrotation von festem Toluol und Toluolderivaten
Authors: Haupt J. , Müller-Warmuth W.
Published: February 2015

The hindered rotations of methyl groups have been studied in solid toluene, 2-F-toluene and 3-F-toluene. NMR pulse investigations have been carried out between the melting point and liquid helium temperatures at 14.5 MHz and 40.7 MHz. As in the case of earlier studies on the three xylenes, which have been continued in this work, the motional narrowing of the proton resonance lines was found to persist down to very low temperatures. In comparison with their exponential increase at high temperatures, the spin-lattice relaxation rates 1/T1 decay as a function of reciprocal temperature much less rapidly in the low temperature range. In the transition region, 1/T1 exhibits maxima which are more or less broadened or distorted. In effect, the relaxation at low temperatures is much stronger than that predicted by semiclassical theories.

An explanation of the observed behaviour takes into acount the quantization of the rotational and torsional motion and the coupling between the spin and rotational degrees of freedom on one hand, and the phonons of the lattice on the other hand. At low temperatures, the motion causing nuclear spin-lattice relaxation is reduced to certain torsional transitions between the lowest states, which are connected with tunneling. At high temperatures, the summation of a great number of rotational transitions in the presence of strong coupling to the lattice leads o the "classical" behaviour.

The potential barriers hindering the methyl group reorientations were found to be rather small in all the materials studied: toluene 0.1-0.2 kcal/mole, 2-fluorotoluene 0.50 kcal/mole, 3-fluoro-toluene 0.30 kcal/mole. They are, however, still large in comparison with free molecule data.
Proton Magnetic Resonance Study of Mercury Dimethyl in a Nematic Liquid Crystal
Authors: Englert Gerhard
Published: February 2015

The P.M.R.-spectrum of mercury dimethyl partially oriented in a nematic liquid crystal has been studied. From the ratio of the direct magnetic dipole-dipole interactions of the protons the ratio ξ0/ρ is calculated. ξ0 being the distance of the two parallel planes containing the methyl protons, and ρ being the distance of the methyl protons from the molecular symmetry axis. From this ratio the splitting due to the direct coupling of the protons with 199Hg of spin 1/2, present in about 17% natural abundance, is calculated and compared with the experimentally observed one. Exact agreement is obtained under the assumption that the methyl groups are rapidly rotating and that the direct and indirect 199Hg-H-couplings have like signs. Since the preferred orientation of the long axis of mercury dimethyl is probably parallel to the direction of the magnetic field, the absolute sign of J199Hg, H is found to be negative. Correspondingly it is shown that the sign of JCH3, CH3 is positive. No evidence is found for a possible contribution of the anisotropic part of the indirect couplings.
Nullfeld-Elektronenspinresonanz im Frequenzbereich von 10 MHz bis 200 MHz
Authors: Birkle M. , Geiger A. , Schoffa G.
Published: February 2015

Im Frequenzbereich von 10 MHz bis 200 MHz werden mit der Methode der Hfs-Nullfeldresonanz Hyperfeinstrukturaufspaltungen untersucht. Es handelt sich dabei um Elektronenspinresonanz im Feld eines oder mehrerer Kernspins ohne äußeres Magnetfeld. Die Aufspaltung der Elektronen-niveaus auf Grund von Elektronenspin-Kernspin-Wechselwirkung führt für Radikale, die durch Bestrahlung organischer Substanzen entstehen, meist zu Spektren mit Übergangsfrequenzen bis zu ca. 200 MHz. Es wird kurz der Aufbau und die Wirkungsweise des Nullfeldspektrometers beschrie-ben. Die Anwendungsmöglichkeiten der Hfs-Nullfeldresonanz werden an Hand der Bestimmung der Hyperfeinstruktur-Kopplungkonstanten an bestrahlten organischen Radikalen erläutert, wobei ge-zeigt wird, daß die Hfs-Nullfeldresonanzspektren zur Klärung der Veränderungen der Substanzen durch Bestrahlung wesentlich beitragen.
ESR-Untersuchung der behinderten Rotation der CH2-Gruppe im photolytisch erzeugten H2C — CO — CH3-Radikal
Authors: Golde G , Möbius K , Kaminski W
Published: February 2015

The radical H2C -CO -CH3 was produced in an acetone/H2O/H2O2 solution by photolysis using techniques similar to those developed by LIVINGSTON and ZELDES. The temperature dependence of the ESR spectrum indicates restricted rotation of the CH2-group relative to the rest of the molecule. A complete line-shape analysis of the spectrum at various temperatures leads to Arrhenius-para-meters Ea= (9.4 ± 0.5) kcal/mol and 10log k0 = 12.9 ± 0.3 which can be interpreted in the frame of the simple HMO theory.
Mössbauer-Effekt von 57Fe und 119Sn in Palladiumlegierungen verschiedenen Wasserstoff-Gehaltes
Authors: Mahnig M , Wicke E
Published: February 2015

The isomer shifts of 57Fe and 119Sn in Pd/Fe and Pd/Sn alloys of different compositions have been studied as functions of hydrogen content. In both systems the isomer shifts start to increase steeply at hydrogen contents which bring up the electron concentration in the alloy to 0.55 additional electrons per metal atom (compared to pure Pd). In accordance with results from other experimental methods each Fe atom has been found to donate 3 and each Sn atom 3.5 electrons to the bands of the alloy. The increase of the isomer shift is shown to follow the rise of the Fermi level when the bands are filled up gradually. It can be correlated to Friedel's model of virtual bound states.

The results obtained confirm the connections developed earlier between the absorption of hydro-gen and the electronic structure of Pd and its alloys. They agree with conclusions drawn from magnetic behaviour and from electronic specific heats at low temperatures. They do not verify, how-ever, a direct relation to the lattice constants in these systems. It is not yet obvious how to correlate our results with the value of 0.36 d-holes in pure Pd obtained recently from measurements of the de Haas-van Alphen effect; possible deviations from the rigid-band model are discussed.
Emission from Excited Terminal States of Bound Exciton Complexes
Authors: Reynolds D.C. , Collins T.C.
Published: February 2015

Emission from the excited terminal states of bound exciton-donor complexes has been observed in several II-VI compounds. Studying these optical transitions allows one to determine the donor ionization energies, the electron effective masses as well as the electron g-values in these materials. A good theoretical fit to the experimental data was obtained, using the effective mass approximation. Emission from the excited terminal states of bound exciton-acceptor complexes has not yet been observed in these materials. There is no basic reason why such transitions should not occur. Studying transitions of this type would allow one to obtain fundamental information concerning the acceptor impurities in these materials.
Untersuchungen an Chrom-Leuchtzentren in Magnesiumtitanat
Authors: Dittmann R. , Hahn D. , Stade J.
Published: February 2015

Chromium activated powdery Mg2TiO4 was prepared using the oxides MgO and TiO2 with LiCl as a flux. The preparation was realized by two annealing processes one after another at 850 °C and 1400 °C for activated specimens and for samples without activator.

The excitation spectra were measured at room temperature and 77 K. The difference in remission was investigated at 293 K for activated samples and specimens without chromium and also the difference in absorption for the same samples.

The excitation-, remission- and absorption spectra show three peaks with a different behaviour if the activator concentration increases. Therefore the chromium luminescence centres in the Mg2TiO4 prove to be Cr3+-ions surrounded by six oxygen ions and chromium clusters respectively. The assumption of two different luminescence centres is supported by the results of the emission spectra.

An energy transfer exists between these two types of centres and depends on the activator concentration.
Direct Photodisintegration of 13C below 17 MeV. Reaction 13C(γ,n) 12C
Authors: Aurdal Terje
Published: February 2015

A nuclear model where the single-particle states of the valence neutron are vector coupled to the ground (0+) and first excited (2+) 12C-core states, is considered. The model is applied to calculate total photodisintegration cross sections of the reaction 13C(γ, n)12C for energies below the Giant dipole resonance. The radial wavefunctions in initial- as well as final states are of the Saxon-Woods type.
Investigation of Low Density Supersonic Jets by Means of a Molecular Beam Sampling Technique
Authors: Eckelt W. , Hose H. , Schügerl K.
Published: February 2015

The performace of a supersonic molecular beam equipment is described. Velocity distributions of the particles in low density supersonic jets consisting of Helium, Argon, Methane and/or Ethane were measured by means of a molecular beam sampling technique and a multi-disc velocity analyser. The jets were produced by expanding the gas from an oven with stagnation pressures of 5 to 5000 torr and temperatures of 293 to 950 °K across different converging nozzles into a vacuum chamber.

The Mach numbers as functions of the source Knudsen numbers were calculated using the source flow theory of Sherman and the hypersonic approximation for the translational nonequilibrium of Hamel-Willis and Edwards-Cheng. These calculations were carried out for different intermolecular potentials. The values obtained using this theory are compared with the experimental results.
Wechselwirkung eines kondensierten Stickstoffmolekularstrahls mit einem koaxialen Elektronenstrahl
Authors: Becker E.W. , Hoffmann V.H. , Kessler R.W.
Published: February 2015

Einem von einer Unterbrecherscheibe kurzzeitig freigegebenen kondensierten Stickstoffmole-kularstrahl wird ein Elektronenstrahl koaxial entgegengeschickt. Es zeigt sich, daß der divergent aus der Kanone austretende Elektronenstrahl nach Erreichen des kondensierten Molekularstrahls zur Strahlachse hin umgelenkt und im Molekularstrahl gesammelt wird. Die von dem Elektronen-strahl im kondensierten Molekularstrahl hervorgerufene Ionisierung reicht aus, um eine elektrische Entladung im kondensierten Molekularstrahl zu zünden.
Die Dispersion des Kerr-Effektes. V.
Authors: Kuball H.G. , Galler W. , Göb R. , Singer D.
Published: February 2015

The definition of a complex Kerr constant follows from the description of the interaction of light with molecules in an electrostatic field. The treatment is based on the time-dependent perturbation theory, assuming a quasi continuum of librational states of the molecules concerned.

The Kramers-Kronig relation for the Kerr effect and the electrochromism is deduced from the complex Kerr constant. The results are compared with the measurement of the Kerr effect of one azamerocyanine. For a number of molecules the amplitude of the optical polarizability and of the hyperpolarizability B is calculated for the long wavelength absorption band.
Elektrisches Dipolmoment und Mikrowellen- rotationsspektrum von SiS
Authors: Hoeft J. , Lovas F.J. , Törring T.
Published: February 2015

Stark effect measurements on pure rotational transitions of SiS are described. Measurements on the ground vibra-tional state of the most abundant molecule resulted in the following electric dipole moment:
Bestimmung der elektrischen Leitfähigkeit von Helium aus integralen Lichtbogenmessungen
Authors: Fischer E. , Hackmann J. , Uhlenbusch J.
Published: February 2015

In Ohmic heated plasmas the temperature of the electrons is always higher than the gas temperature. In this case the electrical conductivity can be assumed as a function of the gas temperature and the electric field strength. With this assumption comparing the characteristics of two arcs with different radii the electrical conductivity of an helium arc plasma (1 atm) is determined and reduced to the value for a field free plasma.
Das Temperatur-und Strömungsfeld in einem wandstabilisierten, magnetisch abgelenkten Bogen
Authors: Sauter Karl
Published: February 2015

The influence of the Lorentz forces -caused by a stationary transverse uniform magnetic field -and the thereby induced flow field on a wall-stabilized electric arc in argon is experimentally investigated. The unsymmetrical temperature fields in the arc discharge cross-section for different values of arc current and magnetic field are determined by measuring the continuum radiation absolutely. The material functions of argon are taken from recently published literature; the specific radiation u(T) is evaluated from our measurements.

The convective term of the energy equation provides the component of the flow velocity parallel to grad T; herefrom, together with the continuity equation, the flow field is calculated. The evaluation of the momentum equation shows that within the main part of the arc-cross-section the Lorentz force is essentially compensated by a pressure gradient and not by inertial or viscous forces. The consistency of the results verifies the measurements, the applied material functions and the evaluation procedures.
Light Emission in the VUV by Dissociative Excitation of CH4 with Low-Energy Electrons
Authors: Sroka W.
Published: February 2015

By bombardment of methane with low-energy electrons (0 - 400 eV) the molecule is dissociated in a single collision into excited C and H atoms or into excited H atoms and a free radical. The excited atoms emit a radiation in the vuv (900 Å -1700 Å). The appearance potentials and excitation functions are measured. Approximate values of the cross sections are given. The excitation cross section for the CII-Lines are extremely small (σ ≦ 10-21 cm2), whereas those for the H and CI-lines are of the order of 10-19-10-18 cm2 at 150 eV.
Energies of Excited States of Doubly Ionized Molecules by Means of Auger Electron Spectroscopy Part I. Electronic States of N2
2+
Authors: Stalherm D. , Cleff B. , Hillig H. , Mehlhorn W.
Published: February 2015

A new method, Auger electron spectroscopy, is applied to the study of excited states of doubly ionized molecules. The energies of Auger electrons determine directly the vertical energies of doubly ionized states, because the single Auger process leaves the molecule in a state of double ionization. We have investigated the states of N2
2+ via the K Auger spectrum of N2. The ionization in the K shell was caused by electron impact. The K Auger electrons, analyzed by means of an electrostatic cylindrical mirror analyzer, gave direct evidence for the following states: x1Σg
+, A″ 3Σu
+ ,A3 Πg, c1Πg, d1Σu
+ and e1Σg
+ .Their energies have been measured and are listed below. Also the energy required to ionize N2 twofold in the (σg 2s) orbital has been determined to be (96.5 ± 1.0) eV.
Zum paramagnetischen Verhalten von Palladium-Eisen- und Palladium-Eisen-Wasserstoff-Legierungen / On the Paramagnetic Behavior of Palladium-Iron and Palladium-lron-Hydrogen Alloys
Authors: Frieske H. , Mahnig M.
Published: February 2015

An evaluation for the paramagnetic susceptibilities of Pd/Fe and Pd/Fe/H alloys is proposed which accounts for the filling of the bands by electrons from the iron atoms. The susceptibilities are split into a "band" and an "iron" contribution, the latter of which exhibits Curie-Weiss behavior. Reevaluation of Gerstenberg's data yields a magnetic moment of 5.9 μB per iron atom.

For hydrogenated Pd/Fe alloys the coupling constant characteristic of the "iron" contribution to the susceptibility could be split into two contributions as well, of which the "d-band" contribution depends only on the electron concentration; the limiting values for high electron concentrations are proportional to the iron content of the alloy.

Both separations indicate again that every Fe atom donates 3 electrons into the delocalized states of the alloy.

The magnetic moment found here, however, is not in agreement with results derived from neutron diffraction experiments.
Lichtabsorption von Farbstoff-Molekülpaaren in Sandwichsystemen aus monomolekularen Schichten
Authors: Czikkely V. , Dreizler G. , Försterling H. , Kuhn H. , Sondermann J. , Tillmann P. , Wiegand J.
Published: February 2015

The absorption spectra of cyanine-like dye molecules in monolayer assemblies are investigated. Pairs between two different dye molecules were obtained by superposing monolayers containing the first and second dye respectively. The spectra of these aggregates are compared with the spectra of the corresponding monomers. The spectral shifts are calculated theoretically using a perturbation approach based on the timedependent Schrödinger equation. The electronic interaction integrals are calculated from wave functions given by the onedimensional electron gas theory making allowance for the polarization of the π-electrons and the solvent. A quantitative agreement between predicted and observed shifts and intensity changes is found. It is concluded from our experiments that during the coating process of the second dye layer the dye molecules in this layer are able to diffuse within the layer to form pairs with the dye molecules fixed in the first layer.
Notizen: Kinetic Theory for the Broadening of the Depolarized Rayleigh Line
Authors: Hess Siegfried
Published: February 2015

Collisional and diffusional broadening of the depolarized Rayleigh light scattered by a gas of linear molecules are studied by a kinetic theory approach based on the Waldmann-Snider equation.
Zur Deutung des Energiespektrums von W183
Authors: Näpfel H
Published: February 2015

The energy levels of W183 are calculated in a nuclear model consisting of three point masses. Two of them with equal masses within a fixed distance ρ0 represent the core of the nucleus. The third one, representing the extra nucleon, is assumed to move in a potential of the usual Nilsson type. For the description of the nuclear deformation a term P4 is added. In contrast to former calculations it can be shown that a consistent set of parameters exists which fits the experimental data including the level 7/2 - at 453.1 keV.
γ Transitions in the Decay of 99Mo
Authors: Bashandy E
Published: February 2015

The internal conversion spectrum of γ transitions in the decay of 99Mo has been re-studied using a high resolution double focusing β-ray spectrometer. In addition to γ-rays previously reported, seven more γ-rays could be observed. Internal conversion coefficients and multipolarities of γ transitions are given. Energies, spins and parities of high excited levels in 99Tc are confirmed.
Optical Excitation Functions of Neon in the Vacuum Ultraviolet
Authors: Hertz H
Published: February 2015

Optical excitation functions of Ne I, Ne II, and Ne III spectral lines in the wavelength range of 400 - 800 Å have been measured with electron energies from 0 to 500 eV. The excited ions are formed by electron impact in a single collision process. The (2p)4 3s levels of Ne II become populated via autoionizing states of the neon atom. The excitation functions of the neon resonance lines at 736 and 744 Å are strongly pressure dependent due to radiation imprisonment.
Extremal Compliance Constants for Molecular Vibrations
Authors: Freeman D.E.
Published: February 2015

The occurrence of a stationary or extremal diagonal compliance constant in the general secular equation for molecular vibrations leads to pecularities in the normal coordinates, in the distribution of potential energy among the compliance constants, and in the secular determinant which then possesses a linear factor.
The Proton Magnetic Resonance Spectrum of 15N-Pyrrole
Authors: Rahkamaa Erkki
Published: February 2015

A sub-spectral analysis of the high resolution proton magnetic resonance spectrum of 15N-pyrrole has been performed as an AA'BB'CX spin system. Absolute values of the proton-proton and nitrogen-proton couplings have been determined. It has also been concluded that all three nitrogen-proton couplings are negative. The parameters found in the analysis of the PMR spectra of normal and deuterated pyrroles, have also been briefly reported.