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Facet Publication Year 1980 [X]

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201	Author	K. Scheffler, F. Digel, R. Krieg, H. B. Stegmann	Requires cookie*
	Title	Dynamische ESR-Untersuchungen zur Propellerform der Triphenylmethylgruppe
	Abstract	The ESR spectra of substituted 4-oxyl-3,5-di-tert.butyl-benzyl-triphenylmethyl radicals ex-hibit the expected temperature dependence of the methylene protons, which is explained by internal hindered rotation of the phenoxyl ring. Furthermore, alternating linewidths have been observed. This phenomenon can be assigned to a two jump process between right-and left-handed propeller shapes of the triphenylmethyl substituents. The activation enthalpies depend on the sense of rotation of the phenyl groups and are found to be around 14.3 and 32.6 kj/mol. Obviously the propeller shaped form of the triphenylmethyl group is due to steric reasons.
	Reference	Z. Naturforsch. 35a, 1231 (1980); eingegangen am 9. August 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1231
	Volume	35

202	Author	J. Rathouský, J. Puszynski, V. Hlaváček	Requires cookie*
	Title	Experimental Observation of Chaotic Behavior in CO Oxidation in Lumped and Distributed Catalytic Systems
	Abstract	Measurements of the catalyst temperature and outlet conversion in differential, integral and honeycomb systems give evidence that the catalytic CO oxidation may proceed chaotically in time over a range of inlet CO concentrations and temperatures. Development of aperiodic oscillations from periodic oscillations was experimentally investigated. In distributed systems chaotic be-havior may exist only in a narrow range of inlet temperatures.
	Reference	Z. Naturforsch. 35a, 1238—1244 (1980); received July 26 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1238
	Volume	35

203	Author	P. Rudedci	Requires cookie*
	Title	Cross Sections for Depolarization of 6 2 P 3/2 Cesium Atoms Induced in Collision with Noble Gases from D 2 Optical Pumping
	Abstract	Possibilities of examing the relaxation of alkali atoms in 6 2 P3/2 state by analysing the pumping process with a weak circularly polarized D2 line are presented. Results of an experiment on Cs-He and Cs-Ne systems have also been given. Assuming the J-randomization model for relaxa-tion of alkali atoms in 2 P 3 /2 state and neglecting energy transfer between 6 2 Pj states, we ob-tained the cross sections for relaxation: Cs-He, 02.6 4; 10.0; Cs-Ne, 54.0 + 9.0; in 10~ 16 cm 2 units.
	Reference	Z. Naturforsch. 35a, 1245—1248 (1980); received June 23 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1245
	Volume	35

204	Author	E. Lisicki, A. Bielski, J. Szudy	Requires cookie*
	Title	Collision Broadening and Shift of the 535.0 nm TI Line Accompanying the Photodissociation of Thallium Iodide Perturbed by Noble Gases Part I: Effects due to Kr and Xe
	Abstract	The shape and shift of the 535.0 nm thallium line resulting from the photodissociation of thallium iodide perturbed by krypton and xenon were investigated at low densities. The Doppler and collision broadening components of the line shape have been determined. The linear de-pendence of both the Lorentzian half-width and the shift on the perturbing gas density was found and interpreted in terms of Van der Waals and Lennard-Jones potentials.
	Reference	Z. Naturforsch. 35a, 1249—1255 (1980); received July 16 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1249
	Volume	35

205	Author	M. Fornaris, Y. M. Muggianu, M. Gambino, J. P. Bros	Requires cookie*
	Title	Enthalpy of Formation of Gallium-Germanium-Tin Liquid Alloys: Evaluation of the Liquidus Surface of the Phase Diagram from Excess Functions of Mixing
	Abstract	With a differential high temperature Calvet calorimeter, the enthalpies of formation of Ga-Ge-Sn liquid alloys have been measured at 703, 798, 895, 1000 and 1230 K in the whole concentration area. The experimental results are compared with those obtained by using an interpolation relation on the basis of the excess functions of mixing of the bordering binary systems. The interpolation relation is used to calculate the partial excess functions and to determine the position of the liquidus surface of the Ga-Ge-Sn phase diagram: the experimental and calculated values agree fairly.
	Reference	Z. Naturforsch. 35a, 1256—1264 (1980); received July 28 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1256
	Volume	35

206	Author	A. Gryczyński, Kawski, S. Paszyc, B. Skalski	Requires cookie*
	Title	I
	Abstract	Mean lifetimes in the singlet excited state and emission anisotropics of Ft base and Yf (CH2) 5-adenine were mea-sured as a function of solvent viscosity. Effective volumes of the molecules studied and the cor-responding radii were determined. The fluorescence de-polarization of Yt-base in solutions was found to be due to the rotational motion, for the most part about the main z-axis.
	Reference	Z. Naturforsch. 35a, 1265—1267 (1980); received August 2 1980
	Published	1980
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	Volume	35

207	Author	SiliciumsubstratenR. Braungart, H. Sigmund	Requires cookie*
	Title	Zur Bildung von Mg2Si-und CaSi2-Schichten auf
	Abstract	Thin layers of Mg2Si or CaSi2 (10—20 [zm) on silicon substrates can be prepared by the reaction of the corre-sponding metal vapor with silicon wafers. The resulting poly crystal line silicides have a purity of more than 99.95%; their surface roughness is about 2 [xm. The layer thickness and the dimensions of the crystallites may be controlled by the conditions of the preparation. An oriented growth on the <lll>-silicon surface is observed in the case of CaSi2-The method described seems generally well suited for growing silicide layers of metals with high vapor pres-sure. The Mg2Si-and the CaSi2-layers were used as starting material in a special "sandwich"-epitaxy in order to prepare Mg-and Ca-doped Si-layers. Die Bildung von Mg2Si-und CaSi2-Sehichten auf Siliciumsubstraten wurde in Hinblick auf die Be-stimmung des Segregationskoeffizienten von Magne-sium und Calcium in einkristallinem Silicium unter-sucht, wofür sättigungsdotierte Siliciumschichten benötigt werden, die in einem speziellen Epitaxie-prozeß ("Sandwichverfahren") mittels der Silicid-schichten hergestellt werden [1], Mg2Si-und CaSi2-Schichten von 10—20 [jt,m Dicke entstehen durch die Reaktion von einkri-stallinen Siliciumscheiben [2"-Siliciumscheiben, Dicke 380 p.m, Orientierung <111), spez. Wider-stand 10 Q cm (Fa. Wacker-Chemitronic, Burg-hausen)] mit dem entsprechenden Metalldampf. Man verwendet einen Graphittiegel [Reinstgraphit EK 506, Aschegehalt < 10 pprn (Fa. Ringsdorf, Bad Godesberg)], in dem sich das Metall [Magnesium 99,99% (Fa. Ventron, Karlsruhe); Calcium 99,5% (Fa. Fluka, Neu Ulm)] befindet, und eine einseitig polierte Siliciumscheibe als Tiegelabdeckung (Ab-bildung 1). Durch Verschieben der Heizmanschette läßt sich erreichen, daß die Temperatur der Dampf-quelle um einen gewünschten Betrag A T niedriger liegt als die der Siliciumscheibe. Das
	Reference	Z. Naturforsch. 35a, 1268—1270 (1980); eingegangen am 6. Oktober 1980
	Published	1980
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	Volume	35

208	Author	W. Henke, H. L. Selzle, T. R. Hays, E. W. Schlag	Requires cookie*
	Title	Magnetic Field Dependence of Molecular Quantum Beat: Biacetyl
	Abstract	The effect of an external magnetic field on the decay of an excited single rotational state of the X AU electronic state of biacetyl is observed in a hypersonic jet experiment after narrow bandwidth laser excitation. The lifetime of the ex-cited state decreases already at low magnetic fields and the molecular quantum beat vanishes.
	Reference	Z. Naturforsch. 35a, 1271—1272 (1980); received October 17 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1271_n
	Volume	35

209	Author	A. Salmassi, J. Eichler, C. P. Herz, W. Schnabel	Requires cookie*
	Title	Evidence for Triplet Exciplex Formation in the Reaction of Amines with 1 -Pheny l-2-acetoxy-2-methy 1-propanone-1
	Abstract	l-Phenyl-2-acetoxy-2-methylpropanone-l has been irradiated with 25ns flashes of 347 nm light in benzene or cyclohexane solution. Absorption measurements yielded the following: at the end of the flash the triplet-triplet spectrum was observed (triplet decay rate constant: &t = (3.0 ±0.2) 105 s i). In the presence of aliphatic amines (e.g. triethanol amine) radicals were formed much more slowly than triplets disappeared, as clearly indicated by spectral changes at wave lengths between 330 and 380 nm. The radical precursor thus evidenced is presumed to be an exciplex. Rate constants: + amine: (1.2 + 0.2) 10 9 1/mol s; /."exciplex: (9± 1) 10 6 s -1 .
	Reference	Z. Naturforsch. 35a, 1273—1275 (1980); received October 10 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1273
	Volume	35

210	Author	Herbert-Rainer Petry	Requires cookie*
	Title	Scattering on Magnetic Monopoles
	Abstract	The time-dependent scattering theory of charged particles on magnetic monopoles is investi-gated within a mathematical frame-work, which duely pays attention to the fact that the wave-functions of the scattered particles are sections in a non-trivial complex line-bundle. It is found that Möller operators have to be defined in a way which takes into account the peculiar long-range behaviour of the monopole field. Formulas for the scattering matrix and the differential cross-section are derived, and, as a by-product, a momentum space picture for particles, which are described by sections in the underlying complex line-bundle, is presented.
	Reference	Z. Naturforsch. 35a, 1276—1284 (1980); received June 26 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1276
	Volume	35

211	Author	Jörg Fleischhauer, Eckard Gerlach	Requires cookie*
	Title	Zur approximativen Lösung der Einelektronen-Schrödinger-Gleichung mit Hilfe eines Differenzen-Hamilton-Operators demonstriert am Beispiel des H-Atoms in einer sphärischen Box
	Abstract	For an H-atom in a spherical box with variable radii R it is shown that the energy and the ESR-splitting constant for the groundstate calculated with a difference-hamiltonian are in good agreement with the results obtained by other methods. The dependence of the energy on the number n of discrete points and their distance for a given radius R is considered.
	Reference	Z. Naturforsch. 35a, 1285—1288 (1980); eingegangen am 18. Juli 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1285
	Volume	35

212	Author	H. Stumpf	Requires cookie*
	Title	Functional Quantum Theory of the Nonlinear Spinorfield as a Lepton-Hadron Model with Quark-Confinement. II
	Abstract	The nonlinear spinorfield with Heisenberg's dipole regularization is interpreted as a lepton-quark system. In Section 1, a nonlinear spinorfield equation for two lepton-quark generations is derived by physical arguments and the Heisenberg dipole regularization is formulated for this model. In Section 2, corresponding dynamical equations for local fermion and local boson states are deduced by means of functional quantum theory and their properties are discussed. In Section 3, with this formulation the lowest order »S'-matrix of elastic lepton-lepton scattering is calculated and is shown to be identical with the results of the corresponding process in quantum electrodynamics resp. weak interactions. The coupling of the local bosons to local fermions is universal, i.e. independent of special lepton or quark representations. Numerical calculations of local boson masses and coupling constants will be given in subsequent papers.
	Reference	Z. Naturforsch. 35a, 1289—1295 (1980); received October 24 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1289
	Volume	35

213	Author	H. Rager	Requires cookie*
	Title	Electron-Nuclear Hyperfine Interactions of 53 Cr 3+ in Mg2Si04 (Forsterite)
	Abstract	The magnetic hyperfine interaction between the electron and nuclear spin system of 33 Cr 3+ was studied at the Mg sites, Ml and M2, in Mg2>Si04. The study was undertaken at room tem-perature and 9.52 GHz. The hyperfine structure data exhibit a covalent Cr-0 bonding of ap-proximately 10% indicating a mainly but not purely ionic bonding. Including the corresponding results obtained for 57 Fe 3+ [1] and 55 Mn 2+ [2] in Mg2Si04, this is interpreted such that the bonding of transition metal ions is mainly dominated by the oxygen sublattice in Mg2Si04 and less by the properties of the transition metal ions themselves. The small variation of the hyperfine splitting parameters found for 53 Cr 3 f at Ml and M2, and also for 57 Fe 3+ at these positions in-dicates that the hyperfine interaction varies also with varying average metal oxygen distances as well as with changes in the oxygen coordination size.
	Reference	Z. Naturforsch. 35a, 1296—1303 (1980); received October 25 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1296
	Volume	35

214	Author	ViraalKuraar Jain	Requires cookie*
	Title	EPR Study of Mn 2+ in Hg(Cl04)2 * 6 H20 Single Crystals
	Abstract	The electron paramagnetic resonance of Mn 2+ in Hg(C104)2 • 6H20 has been studied at X-band at 298 K and 77 K. Mn 2f is found to substitute Hg 2+ . The spectra have been analysed using the spin-Hamiltonian appropriate for trigonal symmetry. From the unequal separations between the Am = ± 1 doublets in M — + 1/2 — 1/2 transitions, the value of the axial part of the quadrupole coupling constant is determined. The observed doublet separations of forbidden hyperfine transitions in M — + 1/2 -> — 1/2 are in good agreement with those cal-culated.
	Reference	Z. Naturforsch. 35a, 1304—1307 (1980); received July 9 1979
	Published	1980
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	Identifier	ZNA-1980-35a-1304
	Volume	35

215	Author	VimalKumar Jain	Requires cookie*
	Title	Host Spin-Lattice Relaxation Narrowing in Pr2Co3(N03)12 * 24 H20: Mn 2 \ Gd 3+ Single Crystals
	Abstract	Electron paramagnetic resonance of Mn 2+ and Gd 3+ in single crystals of Pr2Co3(N03)i2 • 24 H2O has been studied at X-band at 305 and 77 K. Mn 2+ substitutes at two types of Co 2 f sites whereas Gd 3 substitutes at the single type of Pr 3+ site in the lattice. The spin-Hamiltonian parameters have been evaluated. Observation of resolved Mn 2+ and Gd 3+ spectra at 305 K and their broadening on lowering the temperature are discussed in terms of host spin-lattice relaxation narrowing.
	Reference	Z. Naturforsch. 35a, 1308—1312 (1980); received January 7 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1308
	Volume	35

216	Author	A. Bernard, A. M. Sibaï	Requires cookie*
	Title	The Spectrum of Lanthanum Oxide: A Reanalysis of the Rotational Data
	Abstract	A consistent set of improved rotational constants is derived for the X 2 27 f , A" 2 ,4r, A 2 77r, B 2 2, v , and C 2 77r electronic states of lanthanum oxide from the reanalysis of all available data. These constants are obtained from a global fit of the respective bands by a "Direct Approach" tech-nique using complete Hamiltonian matrices for the description of 77 and A states. In order to fit the lines accurately it is shown necessary to include centrifugal distortion effects in the spin-orbit interactions (AJ, AJ and AJJ respectively in A', and A and C states) as well as in A-doubling (PJ» pjjy <IJ in C state) and spin-rotation interactions (yj in B state). More reliable values for the internal partition function and dissociation equilibrium constant of LaO are computed for temperatures between 1000 and 8000 K, by taking account of all the known electronic states and using present or recent values for the molecular parameters and dissociation energy.
	Reference	Z. Naturforsch. 35a, 1313—1316 (1980); received October 6 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1313
	Volume	35

217	Author	Marek Łukaszewicz	Requires cookie*
	Title	Temperature Dependence of the 7 2 P States Mixing and Quenching in Caesium-Deuterium Collisions
	Abstract	Temperature dependent mixing and effective quenching cross-sections for the 7 2 P doublet in caesium, induced in collisons with molecular deuterium, were determined experimentally using the sensitized fluorescence method. The character of the temperature dependence exhibits an isotope effect compared to the data for caesium-hydrogen collisions obtained earlier.
	Reference	Z. Naturforsch. 35a, 1317—1318 (1980); received October 17 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1317
	Volume	35

218	Author	R. K. Bauer, A. Baiter, A. Kowalczyk, Ch Jung	Requires cookie*
	Title	Some Luminescence Properties of the Laser Dye Stilbene 3
	Abstract	Absorption and emission spectra o f stilbene 3 (Na-bis-ortho-stilbene-sulphonate) were mea-sured and discussed on the basis of quantum-chemical calculations. The decay of the polarized fluorescence was investigated, yielding information about the rotational behaviour of stilbene 3 in solutions.
	Reference	Z. Naturforsch. 35a, 1319—1324 (1980); received October 6 1980
	Published	1980
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	Identifier	ZNA-1980-35a-1319
	Volume	35

219	Author	H. P. Mital, U. Narain	Requires cookie*
	Title	On Dielectronic Recombination in Some Coronal Ions
	Abstract	Dielectronic recombination rate coefficients for some ions found in the solar corona have been investigated in the temperature range 20—1000 eV using two different expressions. A comparison has also been made with the corresponding radiative recombination rate coefficients.
	Reference	Z. Naturforsch. 35a, 1325—1329 (1980); received August 21 1979
	Published	1980
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	Identifier	ZNA-1980-35a-1325
	Volume	35

220	Author	Fumio Higashino, Stoßwellenlabor, Tateyuki Suzuki	Requires cookie*
	Title	The Effect of Particles on Blast Waves in a Dusty Gas
	Abstract	The effect of suspended particles on cylindrical blast waves is investigated by making use of a series expansion method with respect to i/M 2 take off [2], where M is the shock Mach number. Velocity and temperature equilibrium between the gas and the particles is assumed. As a result, one finds that the particles are assembled near the shock front and that behind it the slopes of the pressure and velocity profiles increase, as the volume fraction of particles increases. The difference between the zeroth and first order solutions becomes the smaller, the larger the volume fraction of the particles. The decay rate of a blast wave in a dusty gas is greater than in a dust-free gas.
	Reference	Z. Naturforsch. 35a, 1330—1336 (1980); received October 10 1980***
	Published	1980
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	Identifier	ZNA-1980-35a-1330
	Volume	35

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