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1984 (209)
1Author    D. PfirschRequires cookie*
 Title     
 Abstract    n d G u id in g C e n te r T h e o r ie s L o c a l C h a rg e a n d E n e rg y C o n s e r v a tio n L a w s A new variational formulation of Maxwell-Vlasov and related theories is given in terms of a common Lagrangian density for both the "Vlasov particles" and the Maxwell fields. This formulation is used to derive in a consistent way, on the one hand, correct charge and current densities and, on the other, corresponding energy and energy flux densities. All of these densities generally show in addition to particle like contributions electric polarization and magnetization terms. By some limiting procedure collisionless guiding center theories with polarization drifts included are also treated. In this way local energy conservation laws are formulated for such theories, which has not been possible up to now. N ew V a r ia tio n a l F o r m u la tio n o f M a x w e ll-V la s o v 
  Reference    Z. Naturforsch. 39a, 1—8 (1984); received September 24 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0001.pdf 
 Identifier    ZNA-1984-39a-0001 
 Volume    39 
2Author    I. L. Caldas, H. TassoRequires cookie*
 Title     
 Abstract    a ria tio n a l F o r m u la tio n f o r T w o -F lu id P l a s m a s in G e b s c h V a ria b le s A variational principle for two-fluid plasmas is obtained by using Clebsch variables. A Hamiltonian formalism is derived and canonical Poisson brackets are defined. 
  Reference    Z. Naturforsch. 39a, 9—12 (1984); received September 24 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0009.pdf 
 Identifier    ZNA-1984-39a-0009 
 Volume    39 
3Author    SchumacherRequires cookie*
 Title     
 Abstract    We study the kinetics of fast electrons in a weakly ionized collision dominated plasma in front of a planar negative wall. For small Debye lengths the potential variation in the boundary layer can be approximated by a potential jump representing the space charge sheath. We propose an approximation method to calculate the electron distribution function which accounts for general boundary conditions (absorption, reflection and emission). This method is based on a paramet-rization of the angular dependency, the unknown parameters being determined by a suitable adaption of the Method of Weighted Residuals. The error inherent in our approximation procedure is discussed and shown to be small. As result we get a straightforward analytic repre­ sentation of the electron distribution function in the boundary layer. For the special case of a totally absorbing wall our results are in good agreement with exact analytical solutions in the literature. R e la x a tio n o f E le c tr o n s in th e B o u n d a r y L a y e r o f a W e a k ly Io n iz e d P la s m a 
  Reference    Z. Naturforsch. 39a, 13—21 (1984); received July 12 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0013.pdf 
 Identifier    ZNA-1984-39a-0013 
 Volume    39 
4Author    Siegfried HessRequires cookie*
 Title      
 Abstract    In flu e n c e o f a n O r ie n tin g F ie ld o n th e V is c o s ity o f a M o le c u la r L iq u id 
  Reference    Z. Naturforsch. 39a, 22—26 (1984); received October 14 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0022.pdf 
 Identifier    ZNA-1984-39a-0022 
 Volume    39 
5Author    A. Bernard, R. GravinaRequires cookie*
 Title     
 Abstract    u rth e r A n a ly s e s o f I n fr a re d !/7 lI B a n d s o f 89Y 127I : N ew S p e c tr o s c o p ic D a ta o n S t a te s u p to v " = 7 a n d v ' = 4 This paper deals with the extension of a recent study of the infrared ]fl -* 11 emission system of the YI molecule (1). Thanks to the extreme regularity of the structure, rotational analyses can be completed for the previous 3-1, 2-0, 1-0, 0-0 and 0-1 bands and extended to 11 more bands detected step by step from their synthetic spectra (owing to the extremely dense structure). A unique and consistent set of accurate rotational constants is derived for both states, up to the levels v" = 7 and r' = 4, from the reduction of 5772 line wavenumbers in the bands 3-1, 2-0, 1-0, 0-0. 0-1. 0-2, 1-3, 2-4, 2-5, 3-6 and 4-7, the r-connected bands being fitted simultaneously. The 57 estimated constants allow to reproduce the observed spectra with typical weighted rms errors between 4 and 5 mK. When using these constants to generate the bands 2-1, 1-2, 3-3, 1-4 and 3-5, ~1300 lines can be picked out whose experimental positions relatively to the predicted ones correspond to quite equivalent rms errors with nearly normal distributions of the residuals, therefore ensuring the reliability of the analysis. Molecular constants at equilibrium are derived; improvments are significant, particularly for vibration. Franck-Condon factors and r-centroTds appropriate to RKR potential curves are given. The observed bands correspond to those which are predicted to be the strongest ones in each ('-progression. 
  Reference    Z. Naturforsch. 39a, 27—31 (1984); received November 2 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0027.pdf 
 Identifier    ZNA-1984-39a-0027 
 Volume    39 
6Author    Z. NaturforschRequires cookie*
 Title      
 Abstract    The low temperature behavior of solutions of zinc bromide in ethyl acetate has been studied by viscosity measurements and differential thermal analysis. It is shown that the solutions go through a glass transition at temperatures between 100 K and 220 K. With decreasing tempera­ ture, rj{T) behaves first Arrhenius-like and then obeys the Fulcher relation. A reduction of the viscosity with respect to that of the pure solvent {rj%) gives a family of curves converging to one point at high temperature; if moreover In (rj/t]s) is plotted vs. the inverse of the reduced tempera­ ture 777g, Tg being the glass transition temperature, the plots coincide within 5% for all solu­ tions. A simple relation between the reduced viscosity and the lone entropy is found, since one obtains din (rj/rj^/d (Tg/T) = i (Tg/T — T%). Comparison is made with the Adam-Gibbs model. The properties of these^glass-forming electrolytes are assumed to be due to a "granular" structure which becomes quasi-polymeric at high concentration. A V is c o s ity -T e m p e ra tu re S tu d y f o r a G la s s -F o r m in g -N o n A q u e o u s E le c tro ly te : Z in c B ro m id e in E th y l A c e ta te 
  Reference    Z. Naturforsch. 39a, 32—40 (1984); received June 21 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0032.pdf 
 Identifier    ZNA-1984-39a-0032 
 Volume    39 
7Author    W. Rettig, M. ZanderRequires cookie*
 Title    Ü  
 Abstract    b e r die L ö s c h u n g v o n " T w is te d I n tr a m o le c u la r C h a rg e T r a n s f e r " (T I C T) -F lu o r e s z e n z e n d u r c h ä u ß e r e S c h w e r a to m -S tö r e r On the Quenching of Twisted Intramolecular Charge Transfer (TICT) Fluorescence by External Heavy-Atom Perturbers The quenching by methyl iodide and ethyl bromide of the TICT fluorescence of N-(p-cyano-phenyl)-carbazole (II) and N-(l-naphthyl)-carbazole (III) has been studied in solvents of different polarity. It is found that the heavy atom induced bimolecular fluorescence quenching increases with increasing energy of the TICT fluorescence transition, contrary to the energy-gap-rule, and that TICT states are much less readily quenched than locally excited (LE) states. These results are explained by assuming a very small S-T energy gap for TICT states and a solvent polarity dependent distribution function for the intramolecular twist angle. 
  Reference    Z. Naturforsch. 39a, 41—48 (1984); eingegangen am 29. Oktober 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0041.pdf 
 Identifier    ZNA-1984-39a-0041 
 Volume    39 
8Author    H. O. Villar, E. A. Castro, R. A. RossiRequires cookie*
 Title     
 Abstract    r a g m e n ta tio n R a te s o f A r o m a tic R a d ic a l A n io n s a n d th e te* — <r* O r b ita l C r o s s in g P o i n t The reaction coordinate of the fragmentation of aromatic radical anions with nucleofugal groups was studied by the INDO and MNDO techniques. The reaction coordinate turned out as the stretching between the nucleofugal group bonded to the carbon atom of the aryl moiety. It was found that to fragment a n* radical anion, the odd electron has to be transferred to the a* molecular orbital of the aryl-nucleofugal bond by an orbital crossing, which is reached by the lengthening of this bond. There is a qualitative agreement between the length of the bond to reach the orbital crossing point and the experimental fragmentation rates of the aromatic radical anions. Finally, some considerations about the a—n coupling are made, since it is defining the possibility of a transfer from the n* to the a* molecular orbital. 
  Reference    Z. Naturforsch. 39a, 49—54 (1984); received June 20 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0049.pdf 
 Identifier    ZNA-1984-39a-0049 
 Volume    39 
9Author    Dirk Hübner, DieterH. SutterRequires cookie*
 Title     
 Abstract    o le c u la r V a lu e s, M a g n e tic S u s c e p tib ility A n is o tr o p ic s , M o le c u la r Q u a d r u p o le M o m e n ts a n d th e A n is o tr o p ic s in th e E le c tro n ic C h a r g e D i s tr i b u ti o n in H N 0 2-C is, D N C h -C is , H N 0 2-T r a n s , a n d D N 0 2-T r a n s The rotational Zeeman effect of the trans and eis forms of nitrous acid has been studied to yield the diagonal elements of the molecular g-tensor and the anisotropics in the diagonal elements of the magnetic susceptibility tensor. The results are used to calculate the diagonal elements of the molecular electric quadrupole moment tensor and the anisotropics in the second moments of the electronic charge distribution for all four molecular species. These data are compared to the corresponding CNDO/2 values, and the CNDO/2 value for the out of plane second moment of the electronic charge distribution is used together with the experimental anisotropics in the second moments of the electronic charge distribution to derive a semi-experimental value for the molecular bulk susceptibility which is otherwise difficult to obtain. The out-of-plane minus average in-plane magnetic susceptibility anisotropy is discussed with reference to the model of localised atomic susceptibilities and it is shown that the model should be extended to include bond and bond-bond interaction contributions. 
  Reference    Z. Naturforsch. 39a, 55—62 (1984); received October 12 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0055.pdf 
 Identifier    ZNA-1984-39a-0055 
 Volume    39 
10Author    D. Hübner, D. H. SutterRequires cookie*
 Title     
 Abstract    ib r a tio n a l D e p e n d e n c e in th e M o le c u l a r G -a n d S u s c e p tib ility -T e n s o r s o f S u lfu r D io x id e The high field rotational Zeeman effect of S02 molecules in the first excited state of the bending vibration has been studied under high resolution. Within the experimental uncertainties no r-dependence is observed for the magnetic susceptibility anisotropies, and the observed r-dependence in the g-tensor elements appears to be essentially caused by the t-dependence of the rotational constants. If this finding may be generalized to all small amplitude vibrations, prospects for sign of the electric dipole moment determinations from rotational Zeeman effect studies of different isotopic species are brighter than expected hitherto. 
  Reference    Z. Naturforsch. 39a, 63—65 (1984); received November 26 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0063.pdf 
 Identifier    ZNA-1984-39a-0063 
 Volume    39 
11Author    W. K. Müller-Warmuth, -H Duprée, M. PragerRequires cookie*
 Title     
 Abstract    e th y l T u n n e llin g a n d R e o r ie n t a t i o n in th e S o lid T e tr a m e th y l C o m p o u n d s o f S ilic o n , G e r m a n iu m T in a n d L e a d , a n d in M e th y l L ith iu m Quantum-mechanical tunnelling and thermally activated reorientation of methyl groups have been studied in the series compounds X(CH3)4 with X = Si, Ge, Sn, Pb and LiCH3 using NMR and. if possible, neutron scattering (INS and QNS) techniques. The temperature and frequency dependence of the relaxation rates \/T\ and \/T\g mirror the transition from small to large tunnel splittings as the barrier to rotation decreases in the succession X = Si. LiCH3, X = Ge, Sn, Pb. The various relaxation maxima, correlation times and apparent activation energies have been discussed in terms of current theories. Using the NMR, INS, QNS results and available literature data, relationships between tunnelling and temperature, activation, molecular structure and potential functions have been derived. Potential barriers decrease from about 7 to 0.2 kJ/mol and the symmetry is not far from threefold. 
  Reference    Z. Naturforsch. 39a, 66—79 (1984); received October 17 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0066.pdf 
 Identifier    ZNA-1984-39a-0066 
 Volume    39 
12Author    Takashi TsuchiyaRequires cookie*
 Title     
 Abstract    n E x a c tly S o lv a b le D iffe re n c e E q u a t io n t h a t G iv e s P u r e C h a o s fo r a C o n tin u o u s R a n g e o f a P a r a m e t e r A one-dimensional first-order nonlinear difference equation which is an extended version of currently well-studied systems is presented and solved analytically. From the exact solution it is shown that for a continuous range of a parameter of the system (i.e., 1) nonperiodic solutions behave in a purely chaotic fashion, whereas for k2 = 1 the exact solution converges to a unique attractor. 
  Reference    Z. Naturforsch. 39a, 80—82 (1984); received September 13 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0080.pdf 
 Identifier    ZNA-1984-39a-0080 
 Volume    39 
13Author    L.K L Guinand, E. Hobt, E. Mittermaier, A. Rößler, Schwenk, H. SchneiderRequires cookie*
 Title    09A g N M  
 Abstract    R -S tu d y o f th e S e le c tiv e S o lv a tio n o f th e A g + I o n in S o lv e n t M ix tu r e s o f W a te r a n d th e O r g a n ic S o lv e n ts : P y rid in e , A c e to n itrile , a n d D im e th y l S u lf o x id e In mixtures of water (W) and one of the organic solvents pyridine, acetonitrile, and dimethyl sulfoxide (O), the silver ion forms the following solvate complexes: AgW2, AgWO, and Ag02. The chemical shift of 109Ag is strongly affected by the ligating solvent molecules, and replacing the ligand W by one of the three organic ligands yields a higher Larmor frequency. In solvent mixtures, only a single resonance line has been observed because of rapid chemical exchange. The measured chemical shifts in the range up to 400 ppm are mean values of the chemical shifts of the different solvate species in a given mixture, weighted with their relative concentrations. The 109Ag chemical shifts were determined for 0.05 to 0.15 molal solutions of AgN03, as functions of the mole fractions of the solvent components. Using a Gaussian least squares fitting routine, the individual chemical shifts of the Ag+ solvate complexes and the corresponding equilibrium constants were determined. This fit was successful for the whole mole fraction range of DMSO, while in the solvent systems with acetonitrile and with pyridine at higher concen­ trations of the organic component the chemical shift is influenced by more than two solvent molecules. In these cases equilibrium constants were calculated from chemical shift data for solutions of low mole fraction of acetonitrile and pyridine. 
  Reference    Z. Naturforsch. 39a, 83—94 (1984); received October 81983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0083.pdf 
 Identifier    ZNA-1984-39a-0083 
 Volume    39 
14Author    AdelN. Asaad, FayezY. KhalilRequires cookie*
 Title      
 Abstract    A kinetic study of the acid-hydrolysis of diethylmalonate in water and dioxane-water mixtures covering the range 0-95% (w/w) of dioxane is reported. The reaction rate is inversely propor­ tional to the organic content of the medium up to about 80% (w/w) then, after passing through a minimum, it becomes directly proportional as the dioxane cosolvent is further added. The kinetic ratio ky/k2 is independent of the solvent composition. The observed activation energies, thermo­ dynamic parameters and radii of the activated complexes along the whole range of solvent composition, for the two consecutive steps of the reaction, are computed. Electrostatic theories favour an interaction in which an ion and a molecular dipole are involved. Application of the reactivity-selectivity principle (RSP) to the present reaction in comparison with that for diethyl-succinate. under different conditions of temperature and solvent composition, is presented. K in e tic a n d T h e rm o d y n a m ic S tu d y o f th e A c id -C a ta ly s e d H y d r o ly s is o f D ie th y lm a lo n a te in D io x a n e -W a te r M ix t u r e s 
  Reference    Z. Naturforsch. 39a, 95—101 (1984); received August 8 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0095.pdf 
 Identifier    ZNA-1984-39a-0095 
 Volume    39 
15Author    MichaelH. PalmerRequires cookie*
 Title     
 Abstract    h e G ro u n d a n d Io n is e d S ta te s o f S 2N 2; A b in itio C o n f ig u r a tio n I n te r a c t io n S tu d ie s o f th e U V -P h o to e le c tr o n S p e c tr u m Ab initio CI calculations using a large spd-basis with polarisation functions have been ob­ tained for the ground state of S2N2 and for many doublet state radical cations of each symmetry. All valence shell electrons were considered in the CI, leading to markedly lower energies than previous work. All doublet states down to about 20 eV have probably been found -this leads to a more general description of the UV-photoelectron spectrum, but the principal IP's are still assigned according to our previous work. Some deficiencies in the Green's Function/Tam Dancoff Method have been noted. The principal groups of shake-up states seem to agree with weak structure in the observed spectrum. 
  Reference    Z. Naturforsch. 39a, 102—108 (1984); received October 15 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0102.pdf 
 Identifier    ZNA-1984-39a-0102 
 Volume    39 
16Author    Hans BergerRequires cookie*
 Title    Comments on "A Geometrical Correction for Precise Lattice Constant Determ ination" by Bradaczek, Leps, and Uebach  
 Abstract    The expression for diffracted X-ray intensity as a func­ tion of absorption and asymmetry derived by Bradaczek et al. [1] is already contained in the general integrated-in-tensity formula. It is interpreted incorrectly by these authors with regard to the correction of precision lattice constants. In a recent paper Bradaczek, Leps, and Uebach [ 1 ] have derived the expression 
  Reference    Z. Naturforsch. 39a, 109—110 (1984); received October 12. 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0109_n.pdf 
 Identifier    ZNA-1984-39a-0109_n 
 Volume    39 
17Author    H. RagerRequires cookie*
 Title    Proton and Fluorine Spin-Lattice Relaxation in Polycrystalline CoSiF6 * 6 H20  
 Abstract    The spin-lattice relaxation times F, ('H) and 7, (l9F) in CoSiF6 • 6H-.0 have been measured at 30 MHz in the tem­ perature range 150K^F^400 K Both F,('H) and r, (l9F) decrease sharply at the phase transition tempera­ ture of 246 K (cooling cycle). The main relaxation mecha­ nism is assumed to be an Orbach process. From the 7", data an average splitting of the Co2+ ground state of about 400 cm"1 in both phases is obtained. The splitting is mainly caused by spin orbital coupling. 
  Reference    Z. Naturforsch. 39a, 111—112 (1984); received October 19. 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0111_n.pdf 
 Identifier    ZNA-1984-39a-0111_n 
 Volume    39 
18Author    Fritz Bopp, Z. NaturforschRequires cookie*
 Title      
 Abstract    To he or not to be as basic question in quantum physics The question is often asked how to interprete quantum physics. That question does not arise in classical physics, since Newton's axioms are immediately connected with basic ideas and experi­ ences. The same is possible in quantum physics, if we remember how elementary particle physicists describe their experiments. As Helmholtz has pointed out. the basic assumption of classical physics is that of gene-identity. That means: Bodies remain the same during their motion. Obviously, that is no longer true in quantum physics. Particles can be created and annihilated. Therefore creation and anni­ hilation must be considered as basic processes. Motion only occurs, if a particle is annihilated in a certain point, if an equal one is created in an infinitesimally neighbouring point, and if this process is continuously going on during a certain time. Motions of that kind are compatible with the existence of some manifest creation and annihilation processes. If we accept this idea, quantum physics can be derived from first principles. As in classical physics, we know therefore what happens from the very beginning. Thus questions of interpreta­ tion become dispensable. A particular mathematical method is used to exhaust continua. The theory is formulated in a finite lattice, whose point density and extension equally go to infinity. All calculations are there­ fore performed in a finite dimensional Hilbert space. The results are however related to an infinite dimensional one. Earlier calculations may, therefore, be essentially correct, though they must be rejected in theories which are based on manifestly infinite dimensional Hilbert spaces. Here limiting processes do not occur in the state space. They are only admissible for numerical results. 
  Reference    Z. Naturforsch. 39a, 113—131 (1984); eingegangen am 15. Juli 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0113.pdf 
 Identifier    ZNA-1984-39a-0113 
 Volume    39 
19Author    Utaro FurukaneRequires cookie*
 Title     
 Abstract    h e B e h a v io u r o f P o p u l a ti o n in a P l a s m a I n te r a c tin g w ith a n A to m ic G a s The processes leading to the population inversion are investigated in a recombining hydrogen plasma which is interacting with a cool and dense neutral hydrogen gas by using the rate equations on the basis of a collisional-radiative (CR) model and the energy equations for electrons, ions and neutral particles. The quasi-steady state (QSS) approximation is used only for the levels i lying above a certain level /* which is not the first excited level. The calculations have shown that the quasi-steady state cannot be realized while intense energy-flows due to the collisional processes exist between different kinds of the particles such as the electrons and the ions in the plasma, and that the population inversion is realized only in the quasi-steady state following the transient phase. The effects of the initial conditions of the hydrogen plasma and of the introduced neutral hydrogen gas on the overpopulation density are also discussed. 
  Reference    Z. Naturforsch. 39a, 132—141 (1984); received October 11 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0132.pdf 
 Identifier    ZNA-1984-39a-0132 
 Volume    39 
20Author    R.K Roy Choudhury, Barnana GhoshRequires cookie*
 Title     
 Abstract    o rel S u m m a tio n M e th o d a n d F i r s t O r d e r P e r t u r b a t i o n F o r m u la fo r th e P o te n tia l V (r) = F / r 2 + G / r + H / { r + z 1) The Borel Summation Method is applied to obtain a first order formula for the bound states for the potential V(/ •) = F /r + G/r + H/(r + r2). For small H our formula reproduces the numerical results given by Znojil. 
  Reference    Z. Naturforsch. 39a, 142—144 (1984); received October 31 1983 
  Published    1984 
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 TEI-XML for    default:Reihe_A/39/ZNA-1984-39a-0142.pdf 
 Identifier    ZNA-1984-39a-0142 
 Volume    39 
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