bluuebunny/crossref_metadata_2025 huggingface dataset:
Untersuchungen am Elektronenstrahlplasma
Authors: Herrmann Winfried
Published: March 2015

The beam plasma exists in at least two states: The “quiescent” state with low pressures and the "turbulent" state with high pressures of the neutral gas (argon in most experiments). The quiescent state is described theoretically. It is shown that the system should transport growing waves with frequencies just below the upper hybrid frequency ωH2=ωp
2+ωc
2. These oscillations are found experimentally for ωp > k1 ωc, where k1 has a value of about 0.35 in the experiments described. Increasing the pressure and the plasma density as well raises the amplitude of the oscillations. Then at the critical pressure the turbulent state with high density is produced very abruptly. The essential feature of this second state is the high energy loss of the beam particles. The dependence of the losses on the parameters of the system is studied in detail. The maximum losses may attain 50% of the original beam energy. Some other properties of the system are described.
Mikrowellenmessungen der Elektronendichte und -stoßfrequenz in elektromagnetisch erzeugten Stoßwellen
Authors: Makios W.
Published: March 2015

Microwave measurements were made of the electron density and the electron collision frequency in the plasma between the shock front and the discharge plasma of electromagnetically produced shock waves. These investigations were carried out in argon and hydrogen at po=2 mm Hg initial pressure and velocities ranging from M=5 to M=20. At higher velocities the discharge plasma advances right into the shock front. A 4-mm-microwave transmission interferometer was used. A system of LECHER wires in the measuring arm of the interferometer provided a spatial resolution of approximately 1 to 2 mm and proved successful in measuring the electron density distribution between the shock front and the following discharge plasma. In the case of hydrogen the rise of the electron density in the shock front is caused by compression of the precursor electrons. In argon, on the other hand, most of the electrons are produced behind the shock front. A typical relaxation of the electron density towards equilibrium was measured. It was also possible to measure the electron collision frequency in argon as a function of time (and hence of the distance from the shock front).
Untersuchung der induzierten Emission von gepulsten Argon- und Xenon-Ionenlasern im sichtbaren und ultravioletten Bereich
Authors: Demtröder W. , Elendt E.
Published: March 2015

Time behaviour, threshold currents and power output of the most intensive induced transitions are investigated in pulsed argon- and xenon-ionlasers in the visible and ultraviolet region. In the 7 mm diameter tube transitions of higher ionized atoms are favoured compared to smaller diameter tubes. Pressure dependence of threshold currents and curent dependence of induced peak power are measured. By observing discharge current, spontaneous sidelight and laser output at the same time, information is obtained about possible excitation mechanisms for various transitions.
Zur analytischen Vorzeichenbestimmung und Bereichsabschätzung von Wechselwirkungskraftkonstanten für Eigenwertprobleme der Ordnung n= 3
Authors: Fadini A.
Published: March 2015

Aus der Grenzwertformel F(λ) =λ·G-1 werden für die Ordnung n=3 die Vorzeichen und Zahlenwerte der Wechselwirkungsgrößen f12(λ), f13(λ) und /23(λ) nach Formeln allgemein berechnet. Dieses Modell wird zur Vorzeichen- und Bereichsabschätzung der Wechselwirkungskraftkonstanten von hinreichend stark frequenzgekoppelten Molekülen des Typs XYZ mit Cs-Symmetrie verwandt. Für diesen Molekültyp XYZ mit Cs-Symmetrie lassen sich für Valenzwinkel α mit 90° ≦ α < 180° vollständig analytische Vorzeichenregeln aufstellen, die keine zusätzlichen numerischen Auswertungen erfordern. Zur Veranschaulichung dieser Vorzeichenregeln und Bereichsabschätzungen dienen die Moleküle HOCl, DOCl und NOF als Zahlenbeispiele.
Koinzidenzmessung von Photoionen und Photoelektronen bei Methan
Authors: Brehm Burkhard , von Puttkamer Ewald
Published: March 2015

A new approach to the experimental investigation of unimolecular decay kinetics is described. It consists of a coincidence measurement of electrons and ions produced by photoionization with monochromatic light. Mass analysis of the ions and energy analysis of the electrons provide unambiguously the needed information. First results on CH4 including CH4
+, CH3
+ and CH2
+ are presented.
Zum Mechanismus der Dotierung von Silicium mit Phosphor bei Anwesenheit einer Oberflächenschicht aus (SiO2)n · P2O5
Authors: Garski Helga
Published: March 2015

The diffusion of phosphorus into silicon out of gaseous P2O5 is rated by a glassy surface layer of (SiO2) n· P205. The dependence of glass composition and sheet resistance of the diffused layer on P2O5-concentration in the reaction zone is examined at constant diffusion time and temperature. There is no simple linear relation. The results can be explained by a discussion of the phase diagram of SiO2—P2O5.

Even at low doping levels far below the solubility limit only part of all phosphorus in the silicon contributes to electrical conduction. The relative part of inactive phosphorus increases with decreasing resistivity.
Die Atomverteilung im glasigen roten Phosphor
Authors: Krebs H. , Gruber H. U.
Published: March 2015

Using a BRAGG—BRENTANO camera followed by a bent quartz monochromator the scattering intensities of amorphous red phosphorous were determined and converted into the atomic distribution curve. Radiation of various wavelengths (CuKa, MοKa, AgKa) were used. Each phosphorous atom is surrounded by three nearest neighbours at a distance of 2.24 Å and six others at a distance of 3.48 A. At a distance of 3.48 Å one also finds on the average almost two more atoms with the VAN DER WAALS distance. The bond angle is about 102°. The close range order must be related to that in the lattices of the polyphosphid MePbP14.

An improved procedure for normalization and for the elimination of the COMPTON scattering is given and discussed.
On the Upper Bound for the Ratio of the First Two Membrane Eigenvalues
Authors: Vries Hans Ludwig De
Published: March 2015

Let λ1 and λ2 (λ1 < λ2) be the two lowest eigenvalues of a membrane. We show that the inequality λ2/λ1 < 2.6578 is always fulfilled, irrespective of the shape of the membrane. This is an improvement upon results due to BRANDS, PAYNE, PÓLYA and WEINBERGER.
Strukturbestimmung von Molekülen des Typs (CH3)3X — C ≡ C — Y mit Hilfe der Methode der Elektronenbeugung an Gasen
Authors: Haase Joachim , Steingross Wolfgang , Zeil Werner
Published: March 2015

Es wird über die Bestimmung der Struktur des Tertiärbutylchloracetylens mit Hilfe der Methode der Elektronenbeugung an Gasen berichtet. Der aus mikrowellenspektroskopischen Messungen erhaltene Abstand der ≡ C—Ct-Bindung von r=1,47 Å wurde durch die Elektronenbeugungsmessungen bestätigt. Die aus den gemessenen Atomabständen ermittelten Bindungswinkel am tertiären Kohlenstoffatom und am Methylkohlenstoffatom werden im Zusammenhang mit der Abhängigkeit der kovalenten Radien dieser Atome vom Winkel diskutiert.
Richtstrahlwertmessungen mit dem Zwei-Blendenverfahren an Elektronenstrahlern mit Kugelkathoden von 250 bis 1,5µm Durchmesser
Authors: Hanszen Karl-Joseph , Lauer Rolf
Published: March 2015

Zum besseren Verständnis der Eigenschaften von Spitzenkathoden wurden Kugelkathoden mit Krümmungsradien, wie sie am Knick von Haarnadelkathoden auftreten, bis hinab zu den Krümmungsradien von Spitzenkathoden systematisch untersucht. Erniedrigt man vom Sperrpotential ausgehend den Betrag der (negativen) WEHNELT-Spannung, so steigt bei den gebräuchlichen Kathodentemperaturen der Richtstrahlwert nur langsam an und erreicht erst bei sehr kleiner WEHNELT-Spannung, d. h. erst bei sehr großem Gesamtstrom seinen Endwert. Dieser stellt sich mit abnehmendem Kugelradius bei WEHNELT-Spannungen ein, die immer näher am Sperrpunkt liegen, d. h. bei immer niedrigeren Gesamtströmen. Diese Abhängigkeit ist durch unterschiedliche Raumladungseinflüsse vor Kugeln und Spitzen zu erklären. — Bei sehr kleinen Kugeln durchläuft der mit der Zweiblendenmethode gemessene Richtstrahlwert in Abhängigkeit von der WEHNELT-Spannung scheinbar mehrere Maxima. Diese Unstimmigkeiten erklären sich durch ein Versagen der Meßmethode: Die Strahlenbündel werden so schlank, daß die Blendenlöcher nicht mehr der Theorie entsprechend ausgeleuchtet werden. Außer diesen „unechten" Maxima gibt es auch echte Maxima in den Richtstrahlwertcharakteristiken. Sie sind darauf zurückzuführen, daß durch Raumladungseinflüsse auch die Emission außeraxialer Kathodenbereiche zum Richtstrahlwert beiträgt.
Quantitative Ausmessung des Fluor-Affinitätskontinuums
Authors: Popp Hanns-Peter
Published: March 2015

The radiation emitted from a cylindric arc burning in SF6-gas at low currents shows the affinitycontinuum of fluorine with a long wavelength threshold of 3646 A. By means of spectroscopic temperature measurements and using KIRCHHOFF’s law the total absorption coefficient for the continuum in the range from 6800 to 2600 A is obtained. Isolating the F-affinity-continuum from the continuous background, the detachment cross section of the negative fluorine ion is obtained as a function of the photon energy.
Mikrowellen-Thermographie
Authors: Koch B. , Oertel Jr. H.
Published: March 2015

It is shown that microwave optical field patterns such as focal areas, field distributions and diffraction phenomena can readily be visualized using CZERNY'S infrared thermosensitive transducer method (Evaporographie).
Further Study on Y Transitions in 140Ce
Authors: El-Nesr M. S. , El-Aassar M. R.
Published: March 2015

A photoline spectrum from the γ rays of energies greater than 200 keV following the decay of 40-hour 140La has been studied using a high resolution double focusing ß-ray spectrometer. The photoelectrons are produced from an uranium radiator of thickness 2.9 mg/cm2. The resulting momentum resolution was 0.3 → 0.8% depending on energy. In addition to γ rays previously reported, we have observed 17 new γ transitions in the energy region of about one MeV to 2.53 MeV. The relative γ-ray intensities have been determined from the external conversion spectrum applying the corrections for the angular dependence of the photo-electric process. Gamma energies and intensities higher than 2.53 MeV have been investigated by means of a scintillation spectrometer using a RiDL-transistorized 400 channel analyzer. A complete set of energy sums was computed in order to survey the possibilities of cascade crossover combinations. Thirteen direct ground state transitions of energies 204.87, 241.95, 993.12, 1597.48, 1973.38, 2026.37, 2350.23, 2371.11, 2410.33, 2530.03, 2900, 3100 and 3471 keV were observed. A few modifications on the previously reported level scheme of 140Ce are proposed after the addition of the 17 new γ rays. Conversion coefficients were obtained by normalizing the ratios of conversion and photon intensities with respect to the 487 keV-E2 transition in 140Ce. From the known internal conversion coefficient of this transition, the absolute K-internal conversion coefficients of the transitions 200.08, 241.95, 273.69, 337.50, 374.81, 400.53 and 875.30 keV were determined to confirm their multipolarities and support spin and parity assignments of the levels 242, 617, 1260, 1323, 2184, 2515, 2585 and 3390 keV.

The absolute K-internal conversion coefficients of the 542.43, 641.41, 752.62, 927.41, 980.19, 1016.20, 1040.31 and 1054.65 keV transitions were measured for the first time. The multipolarity assignments of these transitions were studied on the basis of the conversion coefficients. These measurements together with the previously known assigned levels establish the spins and parities 3-, 0+, 2+, 4+, 2+, and 2+ for the levels 205, 1889, 1973, 2084, 2350 and 2530 keV, respectively. Spin and parity assignments of 1+ and 4- are proposed for the 2900 and 3100 keV excited levels in 140Ce respectively.
Theory of Low-Energy Electron Diffraction
Authors: Kambe Kyozaburo
Published: March 2015

A method for calculating the intensities of diffracted waves in low energy electron diffraction by crystals is proposed. The elastic multiple scattering is fully taken into account. The cellular method of KOHN and ROSTOKER in the band theory of metals is applied to the integral equation of the scattering by two dimensional lattices, particularly by monatomic layers. The solution is expanded in spherical harmonics on the surface of spheres, within which the atomic potential is assumed to be confined.
Mass Spectrometry: The Shapes of “Meta-Stable Peaks”
Authors: Beynon J. H. , Fontaine A. E.
Published: March 2015

The effect on the shape of “metastable peaks” arising from decompositions throughout the whole flight path in a mass spectrometer is considered. The effects of discriminations against product ions are calculated; the effects of finite beam dimensions, angular spreading and kinetic energy of separation of fragments during the decomposition are discussed theoretically and illustrated by practical examples.
Nachlieferung von Elektronen beim Entladungsaufbau in Wasserstoff und Sauerstoff für E/p von 60 bis 3000 Volt/cm Torr
Authors: Schlumbohm H.
Published: March 2015

By analysing the temporal current shapes of electron avalanches the different secondary ionisation processes occuring in H2- and O2-discharges have been separated and data taken. In hydrogen at E/p < 250 volts/cm Torr secondary electrons are released at the cathode by photons emitted mainly from excited states of the WERNER-bands of the H2-molecule. In oxygen secondary electrons are released both within the gas and at the cathode at E/p < 500 volts/cm Torr by photons from electronic states above the first ionisation level of the O2-molecule, which are excited by single electron collisions.

With increasing E/p additional secondary electrons in hydrogen are produced by positive ions at the cathode, but for E/p > 170 volts/cm Torr the avalanche currents cannot be interpreted by the photon and ion processes thus indicating the action of a third mechanism. The same result was obtained for oxygen at E/p > several 100 volts/cm Torr. This additional process is discussed on the basis of different ion species and a possible action of fast neutral molecules resulting from charge exchange collisions.
Berechnung der Oberflächenspannung organischer Flüssigkeiten und kooperative Effekte
Authors: Ulbrich R.
Published: March 2015

It is shown that in a formula derived earlier for the calculation of the surface tension of normal organic liquids one should add an H-bridge-term to the term of the dispersion forces, if the formula is to hold for alcohols and carboxylic acids also. The H-bridge-term is a linear function of the surface concentration of OH-groups resp. COOH-groups. The energy of Η-bridges in liquid alcohols is near 4.1 kcal/mole, and in carboxylic acids 3.6 kcal/mole. It seems reasonable to assume that the (C-H) group in the HCOOH-molecule is an active electron-acceptor.
Interferometrische Untersuchungen an elektromagnetisch beschleunigten Stoßwellen II
Authors: Brinkschulte H.
Published: March 2015

The shock waves produced in T-tubes were investigated with a MACH-ZEHNDER interferometer. The experiments were conducted in hydrogen at an initial pressure of 5 torr. A power crowbar arrangement was used to produce single current pulses. These caused single shock waves to occur with every discharge. Reproducible, non-steady shock waves separated from the discharge plasma were observed at MACH numbers M < 15. By measuring the time dependence of the velocity of the shock front over the entire length of the tube (60 cm) it was found that the shock front behaves in accordance with the homology theory of v. WEIZSÄCKER. From the interferograms it is also possible to determine (but only qualitatively) the drop in density immediately behind the front. As the density jump increases, this drop becomes steeper and steeper—again in agreement with the theory. Moreover, it was shown by side-on photographs taken at various distances from the electrodes that the shock front becomes plane once the shock wave has covered a path ten times longer than the tube diameter.
Eine Methode zur Messung geringster Ölbedeckungen in Vakuumsystemen
Authors: Dobrozemsky R. , Huber W. K. , Viehböck F.
Published: March 2015

To get information on extremely small organic deposits in ultra high vacuum systems the sensitivity of most of the conventional methods for thickness measurements is not high enough. On the other hand the radioactive tracer method has shown its high sensitivity and wide versatility in many fields. Tritium with a half life of 12.3 γ and a mean β-energy of 5.4 keV was choosen as tracer isotope. A method is described for Tritium-labelling diffusion pump oils with specific activities up to 100 mC/g. Using the liquid scintillation counting technique one can detect deposits down to below 1010 molecules/cm2. First results with this Tritium labelled pump fluid are given under different operating conditions in an all metal ultra high vacuum system.
Kernrelaxation und Spindiffusion in organischen Festkörpern mit paramagnetischen Radikalzentren
Authors: Haupt J. , Müller-Warmuth W.
Published: March 2015

This paper discusses the relaxation of proton spins in organic solids due to their interaction with paramagnetic free radicals. It has been shown both theoretically and experimentally that after complete saturation the nuclear magnetization increases initially as a linear function of time. A transient region follows in which the relaxation function is proportional to t1/2. Finally there is the well known exponential region as a consequence of spin diffusion. This characteristic behaviour of “diffusion-limited” relaxation has been found in several organic systems between 77°K and 4,2°K. From the experimental observation of the relaxation function the constants C of direct relaxation, the coefficients D of nuclear spin diffusion and other parameters of relaxation and spin diffusion have been determined. The values of D are of the order of 10-14 to 10-16 cm2/s depending on the particular system and on the vitreous or polycrystalline state of the solid. The results are remarkable with regard to the high barrier radii and the signal losses. These can be explained by only a small averaging of the local fields produced by the electron spins at surrounding nuclei.
Bestimmung der mittleren Agglomeratgröße und des Restgasanteils kondensierter Molekularstrahlen durch Streuung eines K-Atomstrahls
Authors: Burghoff H. , Gspann J.
Published: March 2015

The mean size of the clusters in a condensed nitrogen molecular beam is evaluated from the attenuation of a potassium atomic beam crossing the nitrogen beam at right angles. The method is based on the fact that molecules in a cluster will shield each other and therefore contribute the less in the scattering processes the larger the cluster is. The percentage of unclustered molecules in the condensed beam is determined by measuring the decrease of the potassium beam attenuation resulting from filtering the condensed nitrogen beam with a scattering chamber. Assuming a spherical drop as a model for the clusters the average number of molecules per cluster can be estimated from the measured effective cross sections. It increases from 160 to 6500 when the nitrogen source pressure is increased from 100 to 700 mm Hg. At the same time the percentage of single molecules in the original condensed beams decreases from 30% to 0.15% of the total beam intensity.
Anregung und Dissoziation von Molekülen beim Elektronenbeschuß
Authors: Niehaus Arend
Published: March 2015

Die beim Elektronenbeschuß von N2, Butan, cis-2-Buten, 1,3-Butadien und Hexan entstehenden neutralen Fragmente wurden ionisiert und massenspektrometrisch nachgewiesen, wobei zwischen Bildung und Nachweis weder Wandstöße noch Stöße mit anderen Molekülen stattfanden. Die Bildungswahrscheinlichkeit der Fragmente als Funktion der Energie, von der Schwellenenergie (DP) bis 100 eV, wird angegeben.

DP für N aus N2 ist (9,6 ± 0,5) eV, d. h. für die Dissoziation an der Schwelle ist der Prozeß N2→N2*→2 N (4S) verantwortlich. Die DP-Werte für Fragmente aus Butan und Hexan genügen der Beziehung: DP=E1+D*, wobei E1 die Energie des 1. Elektronenniveaus und D* die jeweilige Bindungsenergie in diesem Zustand (E1 ≈ 8 eV) ist. Die DP-Werte von cis-2-Buten und 1,3-Butadien liegen tiefer und genügen der gleichen Beziehung mit E1=2 -4 e V.

Das Verhältnis (γ) von neutralen Zerfällen zur Ionenbildung liegt bei allen untersuchten Substanzen in der Nähe von 1. Der größte Teil der neutralen Zerfälle erfolgt durch Anregung von „superexcited states“.

Der Nachweis von innerer Anregung durch Messung eines erniedrigten Ionisierungspotentials gelang nur bei dem Bruchstück H2.
Mikrowellenspektrum, Hinderungspotential der internen Rotation und teilweise r0-Struktur des para-Chlortoluols
Authors: Herberich G. E.
Published: March 2015

The rotational microwave spectra of the two chlorine isotopic species of para-chlorotoluene have been measured in the region from 8.4—11.3 GHz. Values for the rotational constants and for the nuclear quadrupole constants have been determined. The barrier to internal rotation of the methyl group is V6 = 13.93 ± 0.04 cal/mole. Two structural parameters have been estimated, namely 1.394 Å for the average ring C — C distance and 1.74 ± 0.01 A for the C — Cl distance.
Einlagerung, Diffusion und Dichteverteilung von Deuteronen in Selbsttargets aus Gold, Nickel und Kupfer
Authors: Heintze V. , Kamke D.
Published: March 2015

The trapping and distribution of deuterons in self-targets consisting of gold, nickel, and copper has been investigated. The analysis of the proton-spectra of the d-d-reaction shows that in gold (5 ... 50 mg/cm2) an inner and a surface part of the D (d,p) T-reaction exists, whereas in a massive gold target all reactions take place within the target; in gold foils having a thickness below 5 mg/cm2 only surface reactions are observed. Likewise, massive nickel and copper targets show only a surface part of the d-d-reaction. An interpretation of these diverse spectra is given. Finally, a simple model of deuterium diffusion in a self-target is developed.
Derivation of the Quantum Vlasov Equation and Dispersion Relation of a Relativistic Electron Gas
Authors: BlSkamp D.
Published: March 2015

The selfconsistent field equation (VLASOV equation) is derived for the one-particle WIGNER function of a relativistic electron-positron gas. From the linearized form we obtain the dispersion relation for any quasi-equilibrium state, which for the special case of thermal equilibrium has already been derived by TSYTOVICH 1.
The Electric Conductivity of Molten (Na—Tl)NO3 Mixtures
Authors: Wagner Vittoriano , Forcheri Sandro
Published: March 2015

Electrical conductivities and densities of molten (Na—Tl)NO3 mixtures have been measured in the temperature range between 192°C and 400°C.

At all compositions the specific conductivities appear to be linear functions of the temperature. While the equivalent conductivities of the mixtures deviate negatively from additivity, the apparent activation energies ΔΕ (from the relation Λ =Λ0 · exp(—ΔE/R T) exhibit positive deviations from additivity.

This behavior is similar to that of other univalent binary systems with a common anion and seems to indicate that the polarization of the nitrate ion due to different cation sizes is the main cause of the additional hindrance to the electrical transport in mixtures.
Interpretation of Electron Transfer Spectra of Iridium (IV) and Osmium(IV) Mixed Chloro-Bromo Complexes
Authors: Jørgensen Chr. Klixbüll , Preetz W.
Published: March 2015

The previous M.O. treatment of unsubstituted hexahalides has been modified, taking the results on Faraday effect obtained at the University of Virginia into account. The absorption spectra previously measured of the complexes (M=Os, Ir) trans-MCl4Br2
— and trans-MCl2 Br4
— are interpreted by a M.O. treatment for the symmetry D4h as electron transfer transitions, including a first-order relativistic (spin-orbit coupling) correction. The concept of holohedrized symmetry is sufficiently valid to allow a description of MCl5Br— and MClBr5
— as if they were tetragonal with centre of inversion and ƒac-(or cis-)MCl3Br3
— as if they were cubic. It is shown that the ligand-ligand antibonding effects have the same order of magnitude as the moderate difference in optical electronegativity between Cl- and Br-.
Diffusion von Tritium in Quarz und Quarzglas
Authors: Matzke Hj.
Published: March 2015

The release of tritium from single crystalline quartz and from fused silica has been measured following 40 keV ion bombardment to a dose of 4 × 1011 ions/cm2. The release can be explained by normal volume diffusion with D0=101±1 cm2 sec-1 for both materials and activation enthalpies of (42 ± 5) kcal/mole for quartz and (52 ± 5) kcal/mole for fused silica. Release from quartz is faster than release from fused silica. This latter diffusion process, however, is essentially slower than diffusion of hydrogen during permeation. Possible reasons for this discrepancy are the existence of radiation damage due to the ion bombardment or the chemical state of hydrogen which cause a different elementary process for mass transport: Hydrogen diffuses in molecular form during permeation whereas probably tritium atoms or ions will diffuse following ion bombardment.
Messung der relativen Häufigkeiten der Xenon-Isotope mit dem elektrischen Massenfilter
Authors: Bruchhausen K. , Gebauer S. , Zahn U. Von
Published: March 2015

The relative abundances of the isotopes of terrestrial xenon were re-determined using a large quadrupole spectrometer. All 11 measured isotopic ratios are in good agreement with the 1950 results of Nier. However, within the error limits a small, but systematic enrichment of the lighter isotopes is noticed in our data compared to Nier's.
Ladungsträgerverluste in einem schwachionisierten stationären Gleichstromplasma im toroidalen Magnetfeld
Authors: Karger F.
Published: March 2015

For the particle losses of a weakly ionized plasma which result from the torus drift in a curved magnetic field, an expression is derived which is valid for certain parameters of the positive column of a gas discharge. To check this theory the “AMBIPOL” device was built. With this device it was possible to determine simultaneously the losses both in the toroidal and in the linear magnetic field by measuring the longitudinal electric field strength. As theory predicts, with growing magnetic field strength a weaker decrease of the longitudinal electric field was observed in the toroidal part of the discharge as compared to the linear part. The measured values of the relative electric field strength, however, exceed the theoretical limit, although the measurements of the electric field in the straight part and the measurements of the particle density and of the electron temperature in the curved part are consistent with theory. Moreover, contrary to the expectations, the onset of the KADOMTSEV instability occurs at lower critical magnetic fields in the toroidal part than in the straight part. Several possible explanations are discussed. In a later paper it will be attempted to make a choice among the three most probable ones.
Photodissoziationen zu elektronisch angeregten Bruchstücken von H2, H2O und NH3 im extremen Vakuum-UV. II
Authors: Beyer K. D. , Welge K. H.
Published: March 2015

Im fernen Vakuum-UV wurden unterhalb von 1000 A Photodissoziationen von H2, H2O und NH3 untersucht, bei denen elektronisch angeregte Bruchstücke auftreten. Der Nachweis der Fluoreszenz erfolgte hauptsächlich im Schumann-UV, zum geringeren Teil auch oberhalb von 2000 A. Durch geeignete Detektor- und Filterkombinationen ließen sich in einigen Fällen die Anregungszustände der Bruchstücke und damit die Dissoziationsprozesse identifizieren und deren Einsatzenergien bestimmen. Die Fluoreszenzintensitäten wurden in Abhängigkeit von der eingestrahlten Wellenlänge untersucht. Für gewisse Zerfallsprozesse konnten absolute Querschnitte gemessen werden.

Beim H2-Molekül tritt im Anregungsbereich unterhalb von 849 A die Dissoziation

(a) H2→ H(n=2)+H(n=1)

auf. Zerfälle mit höher angeregten H-Atomen:

(b) H2→H(n>2)+H(n=1)

kommen unterhalb von 750 A ebenfalls vor.

Beim H2O-Molekül wurden folgende Dissoziationen nachgewiesen:

(c) H2O → H (n=2) +OH (Χ2Π),

(d) H2O → H2(B1∑u+)+O (3P),

(e) Η2Ο → H(n=1) +ΟΗ(Α2Σ+).

Zerfälle mit angeregten O-Atomen im Triplettsystem kommen nicht vor. Die Dissoziationen (c), (d) und (e) setzen unmittelbar bei den jeweiligen Dissoziationsenergien (810 A, 767 A, 1360 A) ein. Angeregte H-Atome und H2-Moleküle entstehen bis 600 A und angeregte OH-Radikale bis etwa 850 A.

Beim NH3 treten zwischen 840 A und 450 A Dissoziationen mit angeregten H-Atomen auf. Bis 750 A kommt von diesen Zerfällen nur der energetisch niedrigste,

(f) NH3 → H(n=2) +NH2

vor. Dissoziationen mit angeregten H2-Molekülen finden nicht statt.

Die absoluten Querschnitte der Zerfälle mit angeregten H-Atomen im (n=2)-Zustand wurden mittels einer Eichung der Lα-Intensitäten durch den H2-Absorptionskoeffizienten bestimmt. Sie sind wellenlängenabhängig und betragen beim H2O bis zu 60 (cm-1) und beim NH3 bis zu 10 (cm-1).
Electrical Mobilities and Tracer-diffusion Coefficients of the Na and Tl Ions in the Molten (Na — Tl)NO3 System
Authors: Forcheri Sandro , Wagner Vittoriano
Published: March 2015

The ionic mobilities and the diffusion coefficients of Na and Tl in the (Na-Tl) NO3 system have been determined by means of a zone electrophoresis and diffusion technique. The most significant feature of the Na mobility isotherm is its rapid variation with composition in the NaNO3 rich region.

The diffusion coefficients of both cations have been found to depend rather weakly on composition. The electrical and diffusional mobilities of both cations show trends opposite to that of the fluidity.

These results are discussed in terms of the anion polarization model.
Mechanical Properties, Electrical Conductivity and Differential Thermal Analysis of Lithium Sulphate with Small Quantities of Potassium Sulphate
Authors: Augustsson Bengt , Kvist Arnold
Published: March 2015

Previously obtained conductivity and viscosity results for the system (Li,K)2SO4 with less than 3 mole% K2SO4 show bad agreement with the phase diagram given in the literature. From conductivity, viscosity and differential thermal analysis we have constructed a new phase diagram for these concentrations.
Verteilungsgleichgewichte und Eigenschaften der organischen Phase im System Salzsäure — Wasser — Diisobutylcarbinol
Authors: Scherff Hans-Ludwig , Herrmann Günter
Published: March 2015

The distribution of hydrochloric acid, water and diisobutylcarbinol (DIBC) between the aqueous and organic phase has been studied at 20°C as a function of acid concentration ranging from 0 to 12 N in the aqueous phase. The density, viscosity, electric conductivity, and dielectric constant of the organic phase have also been measured at 20°C as a function of acid concentration. The acid is extracted as an undissociated ion pair HCl(H2O)2 (DIBC)2 whose composition is derived from the distribution data. The molecular volume of the extracted species obtained from both densities and viscosities, as well as the center-to-center distance of the ion pair derived from conductivities and dielectric constants are in agreement with this formula. With increasing acid concentration, the organic phase behaves more and more like a strongly polar solvent. Hence, the dissociation constant of the acid in that phase increases by more than 20 orders of magnitude. Beyond 8 N aqueous acid, a second species of lower DIBC-content is extracted in addition to the former one.
Unimodular Matrices Homomorphic to Lorentz Transformations in n ≧ 2 Spacelike Dimensions
Authors: Sáenz A. W. , Wigner E. P.
Published: March 2015

We generalize the usual homomorphism between 2 × 2 unimodular matrices B (Λ) and restricted 4 × 4 LORENTZ matrices Λ to the case of one timelike and n ≧ 2 spacelike dimensions. For every such n which is even (odd), this generalization associates homomorphically to each restricted (orthochronous) (n+1)-dimensional LORENTZ matrix a set of Ν × N-dimensional unimodular matrices, where N=2n/2 or 2(n-1)/2, depending on whether n is even or odd. In the case n ≧ 2, we prove the theorem that, if B (Λ) and Β (ΛT) are any two such unimodular matrices associated with Λ and its adjoint ΛT, respectively, then B (ΛT) =ω Β (Λ) t, where ω is an Nth root of unity and † means hermitean adjoint. We also prove that for n>3 one can select these two unimodular matrices so that this equation holds with ω=1, but that no such selection is possible for n=2, 3.
Zur Bewegung ausgedehnter Objekte in der Einsteinschen Gravitationstheorie
Authors: Beiglböck W.
Published: March 2015

Für einen ausgedehnten, mit Hilfe der relativistischen Hydrodynamik beschriebenen materiellen Körper werden hinreichende Bedingungen dafür angegeben, daß seine Trägheitsbewegung im vollen Schwerefeld einer (im Sinne EINSTEINS) gravisch nicht-trivialen Welt streng geodätisch ist. Vorliegende Untersuchung beschränkt sich dabei auf recht spezielle Gravitationsfelder, die durch obengenannte Bedingungen indirekt festgelegt sind.
Erzeugung elektromagnetischer Wellen in Plasmen durch Streuung longitudinaler Plasmawellen an longitudinalen Plasmawellen
Authors: Wagner R.
Published: March 2015

Special interactions of plasma waves are examined in a plasma consisting of protons and electrons in thermodynamic equilibrium. Collisions of particles are neglected. We compute the following two cases: a) interaction of two plane plasma electron waves with each other; b) interaction of one plane plasma electron wave with the thermal fluctuations of the plasma which are represented by thermal plasma electron and ion waves. The electric field originating from the interactions is described by an equation obtained from the system of the MAxwELL–VLAsov-equations for protons and electrons. This equation is solved for the transverse electric field at large distances assuming that the potential energy gained by an electron in the plasma waves is small compared with its thermal energy. For case a) electromagnetic radiation is emitted near 2 cope where ωpe is the electron plasma frequency. For case b) the thermal plasma ion waves yield radio emission close to ωpe, whereas the thermal plasma electron waves yield emission close to 2 cope. The intensities and scattering cross sections for case b) are compared with the results of other authors.
Untersuchung der Emission eines 50 Hz-Rubin-Pulslasers
Authors: Röss D. , Zeidler G.
Published: March 2015

Die quasikontinuierliche Emission eines 1-Zoll-Rubinlasers mit 50 Hz Impulsfolgefrequenz wurde näher untersucht. Die mittlere Leistung von 1 W wird in Einzelimpulsen von 1,3 ms Dauer abgegeben, deren Zeitverlauf besser als 2% reproduzierbar ist, abgesehen von Kurzzeitinstabilitäten mit einer Zeitkonstante kleiner als 100 µs (Spikes).

Das Fernfeld besteht aus Moden bis zur 16. transversalen Ordnung, die sich jedoch glatt summieren, so daß eine zeitlich stationäre Emission ohne erkennbare räumliche Minima entsteht. Die Winkelverteilung wird näherungsweise durch eine Gauss-Funktion gegeben.

Der im kalten Zustand planparallele Resonator verhält sich auf Grund von thermischen Effekten wie ein allgemein konfokaler Resonator mit 100 cm Krümmungsradius der Stirnflächen. Dies führt zu einer Strahlöffnung von etwa 1°, während die echte Divergenz bei 20‘ liegt.

Der zeitliche Einsatz der Laseremission ist wegen der räumlichen und zeitlichen Variation der Pumplichtverteilung eine Ortsfunktion im Strahlquerschnitt. Dies ist im Nah- und Fernfeld gleichermaßen zu beobachten.

Das elektromagnetische Emissionsspektrum wurde mit einer schnellen Photodiode und mit Meßempfängern in einem Frequenzbereich von 10 kHz bis 1 GHz analysiert. Das Spektrum der „spikes“ liegt zwischen 10 kHz und 1 MHz, während die Wechselwirkung der transversalen Moden zu Linien bei einigen 100 MHz führt.
Dynamics of Water in Crystal Hydrates
Authors: Berthold Ingo , Weiss Alarich
Published: March 2015

The crystal structure of Na2S2O6·2 H2O has been refined by means of single crystal X-ray intensity data. The structure of the isotypic Li2S2O6·2 H20 was also determined by single crystal studies. Two dimensional differential FOURIER synthesis revealed the approximate positions of the hydrogen atoms. From 1H-NMR investigations, the crystal structure, and information gained by IR spectroscopy the complete atomic arrangement in these two substances was obtained. The influence of the dynamical behaviour of the water molecules is taken into account in determining the hydrogen positions.
Dynamics of Water in Crystal Hydrates
Authors: Ketudat S. , Berthold I. , Weiss Alarich
Published: March 2015

Deuteron magnetic resonance in Na2S2O6 · 2 D2O single crystals was investigated in the temperature range —68°C to +80°C. The activation energy for the flipping motion of the heavy water molecule was found to be (9.2 ± 1.5) kcal/mole. The quadrupole coupling constant and the asymmetry parameter in the low temperature case was found to be e2 q Q/h= (244 ± 3) kHz, η = 0.103 ± 0.003 for gne deuteron and e q Q/h = (236 ± 3) kHz, η=0.116 ± 0.003 for the other deuteron of the same water molecule. For the fast flipping case at room temperature e2 q Q/h= (131 ± 2) kHz and η=0.77 ± 0.02. Good agreements in structural parameters of the water molecule of Na2S2O6 · 2 D2O and of Na2S2O6 · 2 H2O were found.
Indirekte Kernspinkopplung in den Tetramethylverbindungen der IV. Gruppe
Authors: Dreeskamp Herbert , Stegmeier Gerhard
Published: March 2015

The indirect nuclear spin-spin coupling between protons, C13 and the spin ½ isotopes of the group IV elements (Si29, Sn119 and Pb207) were investigated in the tetramethylcompounds X(CH3)4. Substances enriched in C13 were used. The absorption of the most sensitive nucleus H1 was observed directly while the resonances of the other nuclei were located by a double resonance technique. The normalized coupling constants between directly bonded nuclei were found to be positive in all cases while their magnitudes are in good agreement with a semi-empirical estimate using the contact mechanism. All normalized two-bond X—C—H coupling constants are negative while the three-bond C—X—C—H coupling constants are positive as well as the four-bond H—C—Si—C—H coupling constant. Using these results it is shown that the sign of the normalized X—H coupling constants in the analogous hydrides XH4 are positive confirming a theoretical prediction made in previous work.
Renormalization of the Moment of Inertia for the Classical Electromagnetic One-body Problem
Authors: Madore J.
Published: March 2015

A general process of renormalization of the energy-momentum vector and the angular-momentum tensor is given. It is shown that in the simple limiting case of a charged line segment rotating about a fixed point of symmetry, this process reduces to a renormalization of the moment of inertia analogous to the mass renormalization given by DIRAC for the limiting case of a point particle.
Tritium Loss from Iron Meteorites by Solar Wind Hydrogen
Authors: Wagener K.
Published: March 2015

An estimate of the diffusion loss of tritium from iron meteorites in space cannot be based, in a direct manner, on the results of diffusion measurements in the laboratory, because the hydrogen content of the samples in the laboratory is always higher by many orders of magnitude than is the tritium content of iron meteorites in space, which results from bombardement by cosmic rays. This is true because the kinetics of gas loss from a metal change with concentration and temperature, especially the kinetics of hydrogen loss from meteoritic iron, where the amounts of cosmic rayproduced tritium are sufficiently small to be trapped completely by chemisorption of nickel. Estimates based on diffusion data for hydrogen in the laboratory lead to much higher rates of hydrogen loss than can be expected for cosmic ray-produced tritium in meteorites.

In this connection, however, the fact has to be considered that meteoritic iron in space may not only contain hydrogen isotopes derived from cosmic ray-induced spallation processes, but also derived from solar wind bombardement. The steady-state hydrogen content of an iron meteorite, resulting from such bombardement in outer space, depends, of course, on the size and the structure of the meteoritic body. In general, the body will have to be assumed to possess a grain structure and this complicates the situation considerably. In any case, it can be shown that the steady-state hydrogen content is much higher than the tritium content and this makes it possible to use laboratory diffusion data in a calculation of the diffusion losses of tritium. By using the laboratory data of Festag, Fechtig and Schultes, it can be shown that cosmogenic tritium will be lost almost completely whenever the temperature is close to 0°C, or higher. Only meteorites consisting of grains of a size exceeding several millimeters retain tritium at such temperatures.
Magneto-Photoleitung an Germanium
Authors: Rudolf Kessler Franz , Schmidt Helmut
Published: March 2015

Magneto-photoconductivity measurements were made on intrinsic germanium at temperatures between 300°K and 200°K and magnetic fields up to 22.3 kG. If sufficiently thin samples are used, the interband magneto-photoconductivity spectrum of germanium shows oscillatory character. An analysis of energy field dependence and of the quantitative magneto-photoconductivity spectrum decides - also with respect to the well known magnetoabsorption spectrum - the question of wether it is a case of direct LANDAU transitions or wether exciton levels are involved, in favor of the former.
Elektroden mit Isoporen für Brennstoffzellen
Authors: Thiele H. , Wieschen A.
Published: March 2015

An isoporous diffusion electrode with the characteristics of the well known cylindrical pore model is described. This ideal diffusion electrode is manufactured by metalizing highly crosslinked ionotropic alginate capillary membranes. Silver in dispersed form, reduced by formaldehyde, was found to be a suitable electrochemical catalyst for the oxygen cathode. Current-voltage curves show the performance of the electrodes. In 7 n. KOH at 50°C at a potential of - 500 mV versus the reversible oxygen potential, current densities up to 150 mA/cm2 have been obtained in continuous operation. During a run of about 5000 hours no decrease in performance was observed. The operation pressure of this diffusion electrode, about 50 Torr, is remarkably low.
Elektronenmikroskopische Untersuchungen am kondensierten Wasserstoff, Stickstoff und Sauerstoff
Authors: Bostanjoglo O. , Lischke B.
Published: March 2015

Thin layers of solid hydrogen, nitrogen and oxygen were investigated by means of electron microscopy and electron diffraction down to 3°K. Crystal formation during deposition of the layers, growth of whiskers, phase transformation of hydrogen (fcc, hcp) and oxygen (α, β, amorphous), lattice defects (stacking faults, dislocations) in nitrogen and oxygen and chemical reactions in the solid phase were directly observed.
Landau Damping and Entropy
Authors: Winterberg F.
Published: March 2015

It is shown that the well-known LANDAU-damping entropy paradox can be resolved by considering a macroscopic entropy as defined by CLAUSIUS instead of the microscopic entropy defined by BOLTZMΛNN. Although both entropy definitions are identical for equilibrium configurations, the same in general is not true for non-equilibrium configurations. To extend the entropy definition of CLAUSIUS to non-equilibrium configurations requires a generalization of the concept of temperature to nonequilibrium configurations. A natural generalization of the concept of temperature to non-equilibrium configurations is to put the temperature proportional to the mean square velocity fluctuation. In this way a macroscopic entropy can be defined which is then proportional to the logarithm of the mean square velocity fluctuation. In the case of LANDAU damping it can be shown that two states having the same statistical permutability and thus the same microscopic entropy may have different mean square velocity fluctuations. One should therefore consider, besides the microscopic disorder defined by BOLTZMANN, which is proportional to the logarithm of the permutability, a macroscopic disorder which is proportional to the logarithm of the mean square velocity fluctuation.

In the case of LANDAU damping the microscopic entropy does not change with time; the macroscopic entropy, however, increases steadily with time.
Notizen: Nachweis von Antimon-125 in Hüttenblei
Authors: Kolb W.
Published: March 2015

From scintillation spectrometer measurements it results that certain kinds of recently produced lead may be contaminated with 125Sb probably from atmospheric fallout. The activity concentration of 125Sb in a crude lead sample made from ore concentrate of very low radioactivity was found to be 4 fCi/g. This low value is sufficient to produce additional photopcaks in the background spectrum of a low level scintillation counter, if the material is used as the detector shielding. The 125Sb concentration in lead containing a few percent of antimony will be even higher. For refined lead, however, the probability of contamination is rather low because 125Sb is separated during antimony raffination in the lead smelter.
Calculation of Boson Masses in Higher New Tamm–Dancoff-Approximation in the Nonlinear Spinor Theory
Authors: Saller H. , Dürr H.P.
Published: March 2015

Eigenvalue equations of bosons in the second step of the New Tamm-Dancoff-approximation (NTD) are investigated in the Hermitean formulation of the nonlinear spinor theory.

It is shown that three of the four derived equations lead to the same result, whereas one approximation is completely different and is supposed to give a useless result, because the suppressed 6-point function contains essential parts of the considered 2-point function. It is possible by a factorization of the equations of the second iteration to calculate a local graph. By taking this graph into consideration the eigenvalues of spin-0-particles obtained in lowest NTD are slightly corrected. For comparison the same questions are discussed in case of the anharmonical oscillator.
Zur vollständigen Geometrisierung der physikalischen Welt
Authors: Börner M.
Published: March 2015

Es werden die Strukturmöglichkeiten des RIEMANNschen Raumes untersucht, dem zunächst keinerlei physikalische Eigenschaften zugewiesen werden. Hierzu wird eine lokale Darstellung der Metrik in Normalkoordinaten benutzt. Die auftretenden Normaltensoren sind Tensoren im gesamten affinen Raume, auf dem die Metrik erklärt ist. Die Forderung nach Positiv-Definitheit schränkt durch invariante Tensorgleichungen die Strukturmannigfaltigkeiten entscheident ein und bevorzugt den 3-dimensionalen Raum. Dieser wird durch (natürliche) Randbedingungen, die das Verschwinden der Metrik im Unendlichen ausdrücken, ohne einen weiteren Freiheitsgrad eindeutig festgelegt; Räume geringerer Dimensionszahl sind unter diesen Randbedingungen überbestimmt, Räume höherer Dimensionszahl unterbestimmt. Verschiedene Strukturierungen des so metrisierten 3-dimensionalen Raumes sind nur möglich bei Änderung des Grades der lokalen Entwicklung des metrischen Feldes. Es erscheint denknotwendig, wenn man überhaupt eine Beziehung zwischen Physik und metrischem Raume vermutet, den Grad der lokalen Entwicklung und damit die höchste Stufe der zur Darstellung verwendeten Normaltensoren mit einem nicht-kontinuier-lichen, absoluten Zeitparameter T — 2 zu identifizieren. Es ist dann die Aufgabe gestellt, die so in Raum und absoluter Zeit verfügbaren Strukturen mit den uns geläufigen physikalischen Prozessen anhand ihrer äquivalenten mathematischen Darstellungen zu identifizieren und sie dadurch nicht mehr als Vorgänge im Raume, sondern selbst als strukturierten Raum zu verstehen. Die Konsequenzen werden erörtert.