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1983[X]
101Author    M. BurešRequires cookie*
 Title    Alfven Wave Excitation in a Cavity with a Transverse Magnetic Field  
 Abstract    A transversely magnetized cylindrical plasma model with an internal rod conductor is used to approximate the FIVA internal ring device of Spherator type with a purely poloidal magnetic field. It is shown that an excitation asymmetry along the plasma column, i.e. with a wave number k-=t = 0, introduces a coupling between the magnetoacoustic and shear Alfven waves in the frequency range cu<^o> cj . The introduction of an equilibrium mass motion along the plasma cylinder introduces a flow continuum. Simultaneously the Alfven resonance frequency becomes Doppler shifted. The experimental observations indicate that cavity modes do not build up in the FIVA device in the case of nonsymmetric excitation. If on the other hand the exciting structure becomes symmetric, i.e. with k-= 0, the magnetoacoustic resonances become excited. The result-ing Q values are rather low which indicates that the coupling to the shear wave through the Hall electric field cannot be neglected. 
  Reference    Z. Naturforsch. 38a, 616—624 (1983); received January 24 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0616.pdf 
 Identifier    ZNA-1983-38a-0616 
 Volume    38 
102Author    E. A. WitalisRequires cookie*
 Title    Magnetically Induced Plasma Rotation and Nuclear Fusion  
 Abstract    Introductory views are presented on the physically different but remarkably good fusion reaction performance of the dense plasma focus compared to the mainline magnetic fusion research assemblies. Reference is given to our attempt in explaining a reputed fundamental but not understood phenomenon in the focus plasma by an ion acceleration mechanism of basically the betatron type. Paradoxically, this magnetically induced plasma rotation is both contained in and denied by standard plasma equations, briefly derived and discussed with respect to validity. The neglect of the Hall term in the usual "Ideal MHD Equations" is shown to be in error with regard to current magnetic fusion research plasmas. Magnetically induced plasma rotation is derived from the ion fluid motion equation, from basic MHD fluid equations and by an analysis of the electro-magnetic torque distribution. General validity is proved by invoking usually overlooked consequences of the noncentral character of the forces sustaining quasi-neutrality. Arguments are given in favor of new approaches to magnetic fusion. 
  Reference    Z. Naturforsch. 38a, 625—635 (1983); received December 27 1982 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0625.pdf 
 Identifier    ZNA-1983-38a-0625 
 Volume    38 
103Author    FriedrichFranz SeeligRequires cookie*
 Title    Unrestricted Harmonic Balance A General Method to Evaluate Periodic Structures in Time and/or Space of Arbitrary Stability for Non-linear Chemical Reaction and Reaction-Diffusion Systems IV. Extension to Transcendental Functions  
 Abstract    The method of Unrestricted Harmonic Balance (UHB) as exposed and applied to purely time-dependent systems, stiff systems, and chemical waves in the preceding 3 papers is extended to the case of transcendental functions. So, e.g., exponential functions even in mass action kinetics systems occur, if a wider range of temperature is considered as is the case in continuous stirred tank reactors (CSTR). Here the reaction heat is removed by heat exchangers, but since the volume is in most cases considerable, the system cannot be kept strictly isothermal and instabilities are known to arise. Here the oscillatory case is treated with the method of UHB. 
  Reference    Z. Naturforsch. 38a, 636—640 (1983); received February 12 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0636.pdf 
 Identifier    ZNA-1983-38a-0636 
 Volume    38 
104Author    Günter WermuthRequires cookie*
 Title    Einfluß der Reaktionsenthalpie auf die Bildung von "Twisted Intramolecular Charge Transfer" (TICT) — Anregungszustände in unpolaren Lösungsmitteln: p-substituierte N,N-Dimethylaniline  
 Abstract    The In saturated hydrocarbons dual fluorescence appears both in p-N,N-Dimethylaminobenzo-nitrile (DMABN) and p-N,N-Dimethylaminoethylbenzoate (DMABEE). The temperature-dependence of the fluorescence quantum yield suggests that in DMABEE £(B*) ~ £(TICT) and in DMABN £(B*) <E(TICT). 
  Reference    Z. Naturforsch. 38a, 641—647 (1983); received March 7 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0641.pdf 
 Identifier    ZNA-1983-38a-0641 
 Volume    38 
105Author    C. Kahlert, O. E. RösslerRequires cookie*
 Title    Finite Wavetrains in a One-Dimensional Medium  
 Abstract    A modified Rinzel-Keller equation of reaction-diffusion type is investigated analytically. Both on the ring and on the linear fiber, the possible existence of wavetrains containing an arbitrary finite number of impulses is demonstrated. The longest wavetrain shown explicitly consists of ten pulses. Unlike other approaches, the present method varies many parameters simul-taneously. An implicit algebraic equation is formulated which contains all possible wave solutions of the system. This equation is then solved with a standard technique (Powell's algorithm). The results obtained extend the findings of other authors. The method can be applied, after appropriate modification, to other piecewise linear systems, that is, to other prototype reaction-diffusion systems. 
  Reference    Z. Naturforsch. 38a, 648—667 (1983); received March 12 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0648.pdf 
 Identifier    ZNA-1983-38a-0648 
 Volume    38 
106Author    E. Fliege, H. Dreizler, V. TypkeRequires cookie*
 Title    Centrifugal Distortion and Ground State Internal Rotation Analysis of the Microwave Spectrum of Dimethylsulfoxide  
 Abstract    The torsional Fine structure of dimethylsulfoxide has been reinvestigated with MWFT-spec-troscopy. The higher resolution results in a more accurate determination of the internal rotation barrier F 3 . The centrifugal distortion analysis is extended to sixth order. The prediction of lines is excellent, but some centrifugal distortion constants are poorly determined. 
  Reference    Z. Naturforsch. 38a, 668—675 (1983); received March 12 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0668.pdf 
 Identifier    ZNA-1983-38a-0668 
 Volume    38 
107Author    H. Brodowsky, J. FleischhauerRequires cookie*
 Title    Superconductivity and Critical Field Strengths of Palladium-Boron-Hydrogen Alloys  
 Abstract    Transition temperatures and critical field strengths have been observed on superconducting palladium-boron-hydrogen alloys with different boron to hydrogen ratios. Homogeneous sam-ples. prepared by equilibrium methods, exhibit superconductivity above 3.5 K for boron contents less than .v = 0.07 (.Y = mole boron/mole palladium). Palladium-boron alloys need less hydrogen for reaching a Fixed transition temperature than boron free alloys. Critical field strengths for 7* c = 0 K increase linearly with increasing boron content and reach 3.3 • 10 5 A/m at .Y = 0.044. 
  Reference    Z. Naturforsch. 38a, 676—679 (1983); received June 4 1982 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0676.pdf 
 Identifier    ZNA-1983-38a-0676 
 Volume    38 
108Author    Walter FabianRequires cookie*
 Title    Theoretische Untersuchungen zum Absorptionsverhalten von Benzopyrrol-und Benzodipyrrolderivaten  
 Abstract    In order to explain the unusual absorption characteristics of derivatives of benzopyrrole and benzodipyrrole, PPP-calculations were carried out. By means of configuration analysis the results of these calculations were interpreted in terms of molecular subunits. On the basis of this method the long wavelength absorption of this class of compounds can mainly be ascribed to the large contribution of charge transfer configurations as well as to excitonic interactions. The effect of twisting the N-phenyl bond is discussed. 
  Reference    Z. Naturforsch. 38a, 680—686 (1983); eingegangen 7. Januar 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0680.pdf 
 Identifier    ZNA-1983-38a-0680 
 Volume    38 
109Author    M. Tabata, A. LundRequires cookie*
 Title    ESR of Cation Radicals of Vinyl Monomers in a CF3CCI3 Matrix  
 Abstract    Molecular cations of the vinyl monomers acrolein, methylacrylate and methylmetacrylate have been prepared by irradiation at 77 K of the monomers contained in a CF3CCI3 matrix. The ions have been studied by ESR. The effect of photobleaching has been investigated. 
  Reference    Z. Naturforsch. 38a, 687—692 (1983); received March 8 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0687.pdf 
 Identifier    ZNA-1983-38a-0687 
 Volume    38 
110Author    MagedA. OsmanRequires cookie*
 Title    Molecular Structure and Mesomorphic Properties of Thermotropic Liquid Crystals — I  
 Abstract    The influence of molecular structure on the mesomorphic properties of thermotropic liquid crystals is discussed. The role of intermolecular attractive and repulsive (steric) forces in determining the packing and consequently the mesomorphic behaviour of the molecules is described. A correlation between the geometry of the rigid core of the molecules and the mesomorphic properties is found. The intermolecular separation strongly influences the thermo-dynamic stability of the mesophase. Alkyl chains do not only fill in spaces but also take part in the molecular interactions and affect the packing. 
  Reference    Z. Naturforsch. 38a, 693—697 (1983); received February 23 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0693.pdf 
 Identifier    ZNA-1983-38a-0693 
 Volume    38 
111Author    H. A. Dreeskamp, M. Läufer, ZanderRequires cookie*
 Title    Löschung der Perylen-Fluoreszenz durch Ag + -Ionen  
 Abstract    Quenching of the Perylene Fluorescence by Ag + -Ions The fluorescence of perylene in fluid solution (/. 00 = 440 nm) is quenched by silver ions in a dynamic process according to a Stern-Volmer kinetics (A (/ = 2 • 10 9 [1 • mol" 1 • sec" 1 ], in ethanol at 295 K). Simultaneously an unstruc-tured long-wavelength emission (/. max ~ 470 nm) appears which we assign to a perylene/Ag" exciplex. A similar emission is observed when other polvcyclic aromatic com-pounds (PAC) are used, whose fluorescence as in the case of perylene is not easily quenched in an external heavy atom effect by iodopropane (k q g 10 6). In these cases the excited PAC/Ag T complex is long-lived enough to emit fluorescence since the intersystem crossing to the triplet system is slow due to the absence of an energetically favorable accepting triplet state. 
  Reference    Z. Naturforsch. 38a, 698—700 (1983); eingegangen am 26. März 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0698_n.pdf 
 Identifier    ZNA-1983-38a-0698_n 
 Volume    38 
112Author    J. C. Fayet, F. VarretRequires cookie*
 Title      
 Abstract    By means of Optical Absorption, EPR and Mössbauer techniques it is demonstrated that the addition of small amounts of water to solutions of FeCl 3 in isopropanol enhances the concentration of [FeCl 4 ]" complexes, this ad-dition leading also to the formation of ferric dimers in-volving two Fe 3+ —OH" bridges. An explanation of this fact based on the disproportionation of FeCl 3 and water hydrolysis is reported. 
  Reference    Z. Naturforsch. 38a, 701—702 (1983); received December 29 1982 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0701_n.pdf 
 Identifier    ZNA-1983-38a-0701_n 
 Volume    38 
113Author    Requires cookie*
 Title      
  Reference    Z. Naturforsch. 38a, 703 (1983) 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0703_e.pdf 
 Identifier    ZNA-1983-38a-0703_e 
 Volume    38 
114Author    K. H. Bleuler, S. Hofestädt, H. R. Merk, PetryRequires cookie*
 Title    Nuclear Shell Structure in the Light of Quark Theory  
 Abstract    Realizing that the internal structure of nucleons undergoes appreciable changes through embedding into nuclear matter the finite nucleus is considered from the outset as a correlated system of quarks. As an appropriate approximation scheme we introduce an extended bag model, i.e. a bag with nuclear radius containing all 3n quarks of the n-nucleon system. As the direct interaction we choose a SU(3)-invariant generalized pairing force which is supposed to contain the major effects of the more general term. As a result of the calculations containing a.o. a rigorous diagonalization of the total Hamiltonian, the characteristic properties of the conven-tional (nuclear) shell structure are reproduced: The spin orbit splitting appears now as a property of the relativistic single quark states, and the independent nucleon states are represented by cor-related 3-quark-clusters. In addition, the nuclear radius law follows directly from a normal value of the vacuum pressure. 
  Reference    Z. Naturforsch. 38a, 705—711 (1983); received March 8 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0705.pdf 
 Identifier    ZNA-1983-38a-0705 
 Volume    38 
115Author    R.-DG. Penzhorn, H. Walter, BeerRequires cookie*
 Title    Die chemische Fixierung von Kryptonisotopen in Zeolith 5 A — Voraussetzung für die Messung von 25 keV Neutroneneinfang- querschnitten mit der Aktivierungstechnik  
 Abstract    The Chemical Fixation of Kr Isotopes in Zeolite 5 A. -Prerequisite for the Determination of 25 keV Neutron Capture Cross Sections with the Activation Method By chemical fixation of Kr in zeolite 5A adequate samples can be obtained to determine the capture cross section of reactions such as 84 Kr (n, y) 85 Kr m and 86 Kr (n, y) 87 Kr. The employed zeolite loading was of the order 52-66 [cm 3 STP Kr/g zeolite]. The capture cross section of the reaction 84 Kr (n, y) 85 Kr m was determined at thermal and 25 keV neutron energy. The value obtained at 25 keV is of relevance to the stellar nucleosynthesis of heavy elements. 
  Reference    Z. Naturforsch. 38a, 712—718 (1983); received March 4 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0712.pdf 
 Identifier    ZNA-1983-38a-0712 
 Volume    38 
116Author    D.A S Necsulescu, K. Krausz, KrauszRequires cookie*
 Title    Reliability Theory of Stochastic Fracture Processes in Sustained Loading: Part II, Stochastic Loading  
 Abstract    A Markovian model of crack growth was presented in the first part of the paper. The present Part II presents a model for the case of random load, in order to obtain the probability distribution of the resulting crack size. A general model and the particular cases of a uniformly distributed stress intensity factor and mechanical work, are presented. This model separates the factors producing the crack growth in a homogeneous material from those considered in the Weibull model for nonhomogeneous materials. 
  Reference    Z. Naturforsch. 38a, 719—722 (1983); received August 28 1982 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0719.pdf 
 Identifier    ZNA-1983-38a-0719 
 Volume    38 
117Author    GiacomoM Francesca Martini, OttavianiRequires cookie*
 Title    ESR Study of the Impregnation Process of Silica Gels with CU(N0 3 ) 2 6H 2 0  
 Abstract    The use of electron spin resonance in the study of the different steps in the impregnation process of hydrated Cu(N0 3) 2 onto silica gels with pore size of 20, 50 and 100 nm is described. The desolvation step with concomitant beginning of the salt decomposition step occurred at -100 °C in silica with pores of 50 and 100 nm while a temperature higher than 200 °C were necessary for 20 nm pores. In the range 300 to 500 °C the decomposition step was completed and the adsorption of Cu(II) on =SiO" surface sites started. Well-defined localization was completed after heating at 650 °C. The bond features of the surface adsorbed Cu(II) species are also described. 
  Reference    Z. Naturforsch. 38a, 723—728 (1983); received January 8 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0723.pdf 
 Identifier    ZNA-1983-38a-0723 
 Volume    38 
118Author    FriedrichFranz SeeligRequires cookie*
 Title    Unrestricted Harmonic Balance A General Method to Evaluate Periodic Structures in Time and/or Space of Arbitrary Stability in Non-linear Differential Equation Systems V. Investigation of the Truncation Errors in the Case of an Exactly Solvable Non-linear System  
 Abstract    The method of Unrestricted Harmonie Balance (UHB) is a generally applicable procedure to determine the Fourier coefficients and constants of motion (frequency, velocity) of non-linear periodic phenomena in time and space and was outlined and applied to various problems in chemistry in preceding papers. Here the truncation error is investigated by comparing the UHB results for various truncation harmonics N with the rigorous analytical solution for the Kepler problem which is one of the rare examples of an exactly solvable non-linear problem. 
  Reference    Z. Naturforsch. 38a, 729—735 (1983); received March 28 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0729.pdf 
 Identifier    ZNA-1983-38a-0729 
 Volume    38 
119Author    Thomas Schönherr, Eyring Gerd, Rolf LinderRequires cookie*
 Title    Hochaufgelöste vibronische Spektren von Al(acac) 3 : Cr 3  
 Abstract    Highly Resolved Vibronic Spectra of Alfacac)^: Cr~ Highly resolved emission spectra of Cr 3+ doped Trisacetylacetonatoaluminum(III) have been measured at various temperatures. By comparison with absorption spectra of dilute crystals the three most intense peaks have been assigned to the same molecular zero phonon transition according to three inequivalent Cr }+ sites in the low temperature phase of the host crystal. The usually unobserved ground state splitting has been resolved (1.0 cm -1) in emission spectra at T = 1.9 K. Band assignments are confirmed by ligand Field calculations using complete trigonal perturbation matrices including spin-orbit coupling. From the obtained parameters K = 725 cm -1 and K' = — 600 cm" 1 the trigonal distortion of the chromium complex in the Al-crystal is determined. This indicates that the phase transition of the host crystal leads to rotations of rigid molecules while the molecular geometry remains. 
  Reference    Z. Naturforsch. 38a, 736—739 (1983); received February 26 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0736.pdf 
 Identifier    ZNA-1983-38a-0736 
 Volume    38 
120Author    H. Bürger, R. Eujen, A. Rahner, P. Schulz, J. E. Drake, S. CradockRequires cookie*
 Title    Vibrational Spectra and Force Constants of Symmetric Tops, XXXIII. Rovibrational Analysis of v 6 ,2 v° 6 and 2 vjr 2 of H 3 74 GeI  
 Abstract    The infrared spectrum of monoisotopic H 3 74 GeI has been investigated with a resolution of 0.04 cm -1 in the region of v 6 and 2v 6 . Rotational analyses (o(J, K) ~ 7 • 10 -3 cm -1) of v 6 , 546.117(3), 2v^ 2 , 1094.731(4), and 2vg, 1091.530(4) cm" 1 , have been performed, and vibrational and rotational parameters of the apparently unperturbed v 6 = 1 and 2 states have been obtained. Q branches of hot bands with v 3 and v 6 as lower states have been detected, and the anharmonicity constants .v 36 , .Y 66 and g 66 have been determined. The simultaneous analysis of vg 1 ', 2vJ 2 and 2 v^ 2 -vjf 1 provides an improved A 0 value. 
  Reference    Z. Naturforsch. 38a, 740—748 (1983); received March 10 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_A/38/ZNA-1983-38a-0740.pdf 
 Identifier    ZNA-1983-38a-0740 
 Volume    38 
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