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1997[X]
41Author    Y. NambuRequires cookie*
 Title    Old Wine in New Bottles - Mass Spectra, Bootstrap and Hierarchy  
 Abstract    A brief review is given of the problem of masses and mass spectra, and of an attempt to seek their dynamical origins. 
  Reference    Z. Naturforsch. 52a, 163—166 (1997) 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0163.pdf 
 Identifier    ZNA-1997-52a-0163 
 Volume    52 
42Author    P. RamondRequires cookie*
 Title    Neutrinos: Harbingers of New Theories  
 Abstract    We catalog models with massive neutrinos, emphasizing their uses as probes of physics beyond the standard model. We discuss their experimental implications, in terms of neutrino oscillations and the MSW effect. 
  Reference    Z. Naturforsch. 52a, 167—178 (1997) 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0167.pdf 
 Identifier    ZNA-1997-52a-0167 
 Volume    52 
43Author    Dan-Di WuRequires cookie*
 Title    A Brief Introduction to the Strong CP Problem  
 Abstract    The present status of the strong CP problem is briefly reviewed in a heuristic way. A crisis in EDMN calculation is explained. The equation of vacuum alignment obtained by the author and collaborators last year put a constraint on strong CP parameters. Thus the strong CP will be forced to vanish in one of the three scenarios characterized respectively by axion, zero quark mass and vanishing quark condensate. 
  Reference    Z. Naturforsch. 52a, 179—181 (1997) 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0179.pdf 
 Identifier    ZNA-1997-52a-0179 
 Volume    52 
44Author    F. WinterbergRequires cookie*
 Title    Planck Scale Physics and Newton's Ultimate Object Conjecture  
 Abstract    According to Newton, the ultimate building blocks of matter are hard frictionless spheres. This conjecture is here analyzed under different assumptions, which are: 1. The ultimate objects of matter are frictionless positive and negative Planck mass particles obeying nonrelativistic Newtonian mechanics. 2. The Planck mass particles interact with the Planck force c 4 /G (c velocity of light, G Newton's constant) locally within a Planck length r p , with the positive Planck mass particles exerting a repulsive and the negative Planck mass particles an attractive force. 3. Space if filled with an equal number of positive and negative Planck mass particles, whereby in the average each Planck length volume occupies one Planck mass particle. Making these three assumptions we derive: 1. Nonrelativistic quantum mechanics as an approximation with departures from this approxima-tion suppressed by the Planck length. 2. Lorentz invariance as a dynamic symmetry for energies small compared to the Plank energy. 3. The operator field equation for the previously proposed Planck aether model of a unified theory of elementary particles. In contrast to theories in which the ultimate objects are strings at the Planck scale, the alternative theory proposed here does not need a higher dimensional space, but rather can be formulated in 3 + 1 dimensions. 
  Reference    Z. Naturforsch. 52a, 183—209 (1997); received 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0183.pdf 
 Identifier    ZNA-1997-52a-0183 
 Volume    52 
45Author    W. Schröder, H.-J Treder, HechelstrRequires cookie*
 Title    On Hide's Magnetic Analogue of Ertel's Vorticity Theorem  
 Abstract    The relativistic formulation of Hide's "magnetic analogue" of Ertel's potential vorticity theorem is Dirac's "new classical theory of electrons". 
  Reference    Z. Naturforsch. 52a, 210—211 (1997); received January 8 1997 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0210_n.pdf 
 Identifier    ZNA-1997-52a-0210_n 
 Volume    52 
46Author    Siegfried HessRequires cookie*
 Title    On the Shock Front Thickness in Water and other Molecular Liquids  
 Abstract    Theoretical explanations are presented for the deviation of the shock front thickness from linear hydrodynamics, as observed by W. Eisenmenger (1964) in water and several molecular liquids for large driving pressure differences. Two mechanisms are proposed, which are based on generalizations of the Maxwell relaxation equation for the friction pressure tensor. One is due to the spatial inhomogeneity and linked with piezo-electric or piezo-tetradic effects. The other is caused by nonlinearities which account for shear thickening. 
  Reference    Z. Naturforsch. 52a, 213—219 (1997); received October 29 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0213.pdf 
 Identifier    ZNA-1997-52a-0213 
 Volume    52 
47Author    H. Stumpf, W. PfisterRequires cookie*
 Title    Algebraic Schrödinger Representation of Quantum Chromodynamics in Temporal Gauge and Resolution of Constraints  
 Abstract    The algebraic formalism of QCD is expounded in order to demonstrate the resolution of Gauß constraints on the quantum level. In the algebraic approach energy eigenstates of QCD in temporal gauge are represented in an algebraic GNS-basis. The corresponding Hilbert space is mapped into a functional space of generating functional states. The image of the QCD-Heisenberg dynamics becomes a functional energy equation for these states. In the same manner the Gauß constraints are mapped into functional space. In functional space the Gauß constraints can be exactly resolved. The resolutions are defined by nonperturbative recurrence relations. The longitudinal color electric energy can be expressed by means of these resolvents, which leads to "dressed" color Coulomb forces in temporal gauge. Although present in the system, the longitudinal vector potentials do not affect its energy eigenvalues. This leads to a selfconsistent subsystem within the functional energy equation in temporal gauge which has to be identified with a functional energy equation in Coulomb gauge. In addition this procedure implies a clear conception for the incorporation of various algebraic representations into the formal Heisenberg dynamics and establishes the algebraic "Schrödinger" equation for QCD in functional space. PACS 11.10: Quantum field theory; PACS 12.35C: Quantum chromodynamics. 
  Reference    Z. Naturforsch. 52a, 220—240 (1997); received September 19 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0220.pdf 
 Identifier    ZNA-1997-52a-0220 
 Volume    52 
48Author    Ranjit Pati, T. P. Das, N. Sahoo, S. N. RayRequires cookie*
 Title    Nitrogen Nuclear Quadrupole Interactions in RDX, ß-HMX and Cocaine Systems  
 Abstract    , 1996 Using the Hartree-Fock-Roothaan procedure, the nuclear quadrupole interactions (NQI) of the 14 N (/ = 1) nucleus in the energetically important molecules RDX, ß-HMX and the physiologically important molecule Cocaine, are studied. The coupling constants (e 2 q Q) and asymmetry parameters (r\) for the three ring nitrogens in RDX are found to be -5.671, -5.808 and -5.838 MHz and 0.542, 0.556 and 0.562, respectively, in good quantitative agreement with the experimental results of 5.735, 5.799 and 5.604 MHz for the magnitudes of e 2 qQ and 0.6215, 0.6146 and 0.6024 for rj obtained in the single crystal. For ß-HMX, where two sets of e 2 q Q and rj are expected from symmetry consid-erations, our calculated values are -5.936 and -6.069 MHz for e 2 q Q and 0.432 and 0.490 for r\, compared to experimentally measured magnitudes of 5.791 and 6.025 MHz and ^-values of 0.4977 and 0.5180, respectively, obtained in the single crystal. For Cocaine free base which contains only one 14 N nucleus, our calculated values of <r qQ and r] are -5.038 MHz and 0.067, in very good agreement with the experimental results of 5.0229 MHz for the magnitude of e 2 q Q and 0.0395 for rj. Possible reasons for the small remaining differences between theory and experiment in e 2 q Q and t] for all three systems and the significant differences in trends over the three nitrogens in RDX between theory and experiment are discussed. Also, the calculated quadrupole interaction parameters for the 14 N nuclei in the N0 2 groups outside the ring for both RDX and ß-HMX are presented with the hope that they will be measured in the future to provide a more complete understanding of the electron distributions in these systems. 
  Reference    Z. Naturforsch. 52a, 241—248 (1997); received May 14 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0241.pdf 
 Identifier    ZNA-1997-52a-0241 
 Volume    52 
49Author    A. R. Ofial, S.-Q Dou, V. G. Krishnan, H. Paulus, H. Fuess, Al WeissRequires cookie*
 Title    X-Ray and 35 C1 NQR Studies on the Trichloroacetyl Group in Covalent and Ionic Compounds of L-Valine and DL-Valine  
 Abstract    The crystal structures and 35 C1 NQR of trichloroacetyl-DL-valine (1), trichloroacetyl-L-valine (2), as well as the salts of trichloroacetic acid with DL-valine (3) and L-valine (4) have been investigated. Crystal data are for (1): Monoclinic, C2/c, a= 15.835(4) Ä, b= 10.481 (3) Ä, c = 14.046(4) A, /? = 103.28(1), Z = 8; (2): Orthorhombic, P2 1 2 1 2 1 , a = 12.117(3) Ä, 6=10.896(3) Ä, c= 8.718(2) Ä, Z = 4; (3): Triclinic, PI, a= 17.269(3) Ä, 6 = 8.504(3) Ä, c = 10.427(4) A, a = 105.38(2), £ = 96.98(2), y = 96.24(2), Z = 2; (4): Monoclinic, P2 1? a = 10.378(4) A, 6 = 20.349(8) A, c= 11.890(5) A, B = 95.28(2), Z = 8. The onset of rotational motion within the trichloroacetyl groups bleaches out 35 C1 NQR lines between 115 K and 185 K for (l)-(4). While TCA-L-valine (1), TCA-DL-valine (2), and TCA*) • DL-valine (+) (3) do not show any phase transition in the temperature range 77 K to 295 K, TCA <_) • L-valine (+) (4) shows more than one phase transition above 77 K before the three NQR signals bleach out at 164 K. 
  Reference    Z. Naturforsch. 52a, 249—258 (1997); received August 30 1996 
  Published    1997 
  Keywords    35 C1 NQR study, trichloroacetyl, valine, crystal and molecular structure 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0249.pdf 
 Identifier    ZNA-1997-52a-0249 
 Volume    52 
50Author    Uwe Hoppe, Günter Walter, Dörte Stachel, Andrea Barz, AlexC. HannonRequires cookie*
 Title    Neutron and X-ray Diffraction Study on the Structure of Ultraphosphate Glasses  
 Abstract    The high real-space resolution of neutron diffraction experiments which is provided by use of the epithermal neutrons from spallation sources was exploited in order to differentiate the unlike P-O bonds existing in the P0 4 units of phosphate glass networks. The 2 P-O distance peaks, separated by about 12 pm, which were found in the zinc and the calcium ultraphosphate glasses studied are assigned to oxygen sites on bridging (O b) and terminal (O X) positions. The mean P-O distances are nearly invariable versus the growing metal oxide content which results from an elongation of the P-O b and P-O t bonds. The bond lengths which are known from the related crystal structures and from ab initio calculations show almost the same behaviour. The discussion of further details of the crystal structures leads to the conclusion that P-O b rather than P-O t distances should show more details in case of diffraction measurements of even higher real-space resolution. The change of the Zn-O coordination number from 6 to 4 versus increasing ZnO content, which was obtained in previous X-ray diffraction experiments, is confirmed by the recent combination of neutron and X-ray diffraction data. On the other hand, the Ca-O coordination number of about 6 is almost invariable. 
  Reference    Z. Naturforsch. 52a, 259—269 (1997); received July 6 1996 
  Published    1997 
  Keywords    Neutron diffraction, X-ray diffraction, Phosphate glasses, Short-range order 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0259.pdf 
 Identifier    ZNA-1997-52a-0259 
 Volume    52 
51Author    K. Knopf, W. Waschkowski, A. Aleksejevs, S. Barkanova, J. TambergsRequires cookie*
 Title    Interaction of Slow Neutrons with Cobalt and Tin  
 Abstract    , 1996 Coherent neutron scattering lengths and total cross sections have been measured on samples of Co, Sn and on isotopically enriched Sn-oxides. The following data were obtained: • the coherent scattering lengths (in fm) of the bound atoms 59 Co (2.49 ± 0. New bound levels were evaluated for the investigated nuclei. In combination with the resonance parameters the measured scattering lengths allowed the determination of potential scattering radii R' which are of particular interest for the check of the optical model. 
  Reference    Z. Naturforsch. 52a, 270—278 (1997); received September 19 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0270.pdf 
 Identifier    ZNA-1997-52a-0270 
 Volume    52 
52Author    Nivedita Nag, Anjana Sinha, Rajkumar RoychoudhuryRequires cookie*
 Title    Quantum Deformation of the Non-Polynomial Interaction V(r) = r2 + Ar2 / (1 + 9r2)  
 Abstract    A general scheme for studying g-deformed quasi-exactly solvable problems has been developed using the partial algebraization method. Exact solutions of the deformed non-polynomial interaction generated by the potential V (r) = r 2 + Ar 2 /(1 + gr 2) are obtained. 
  Reference    Z. Naturforsch. 52a, 279—283 (1997) 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0279.pdf 
 Identifier    ZNA-1997-52a-0279 
 Volume    52 
53Author    B. Sedelmeyer, S. SteebRequires cookie*
 Title    Structure of Ni-P Melts by X-Ray Diffraction  
 Abstract    X-ray diffraction was done with molten Ni 81 P 19 (930°C) and with molten Ni 68 8 P 31 2 (1160°C). The second peak of the structure factor and the pair correlation function of the Ni 81 P 19 -melt shows a shoulder, as was observed for amorphous Ni 80 P 20 . The first two peaks in the pair correlation function can be modelled using crystalline Ni 3 P besides molten Ni. In the case of Ni 68 8 P 31 2 , the first peak in the pair correlation function was modelled using the distance and coordination number as in crystalline Ni 2 P. 
  Reference    Z. Naturforsch. 52a, 284—288 (1997); received November 6 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0284.pdf 
 Identifier    ZNA-1997-52a-0284 
 Volume    52 
54Author    A. Kawski, G. PiszczekRequires cookie*
 Title    Temperature Effect on the Absorption and Fluorescence Spectra of p-Cyano-N,N-dimethylaniline in Dichloroethane and Ethyl Acetate  
 Abstract    The effect of temperature (293 -H41 3 K) upon absorption and fluorescence spectra of p-cyano-N,N-dimethylaniline (CDMA) was investigated in 1,2-dichloroethane and ethyl acetate. Two fluo-rescence bands, a and b, were already observed at 293 K, with the intensity of band b increasing strongly with temperature in both solvents. The absorption and fluorescence b bands of CDMA were found to be independent of the orientation interaction with the solvent. On the other hand, the longwave band of fluorescence a undergoes a strong hypsochromic shift resulting from the decrease in the permittivity with increasing temperature. Based on these observations, the electric dipole moment /x e in the *£.,, state (shortwave band of fluorescence b) was found to be equal to the dipole moment, in the ground state. The electric dipole moment n t in the 'L a state (the longwave band of fluorescence a), which is strongly stabilized by the polar solvent, is about 2.5 times as high as n g , amounting to 54 x 10~ 3 ° Cm (16.2 D) for n g = 22.5 x lO -30 Cm (= 6.75 D). 
  Reference    Z. Naturforsch. 52a, 289—292 (1997); received November 13 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0289.pdf 
 Identifier    ZNA-1997-52a-0289 
 Volume    52 
55Author    V. Storm, D. Consalvo, H. DreizlerRequires cookie*
 Title    The Microwave Spectrum of the Benzonitrile-Water Complex  
 Abstract    We report on the measurement and assignment of the benzonitrile-water complex rotational spectrum in the vi-bronic ground state. This study was facilitated by a newly constructed low frequency molecular beam Fourier trans-form microwave spectrometer. 
  Reference    Z. Naturforsch. 52a, 293—294 (1997); received December 2 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0293_n.pdf 
 Identifier    ZNA-1997-52a-0293_n 
 Volume    52 
56Author    Yi-Tian Gao, Bo TianRequires cookie*
 Title    A Symbolic Computation-Based Method and Two Nonlinear Evolution Equations for Water Waves  
 Abstract    A symbolic-computation-based method, which has been newly proposed, is considered for a (2+ l)-dimensional gen-eralization of shallow water wave equations and a coupled set of the (2 + l)-dimensional integrable dispersive long wave equations. New sets of soliton-like solutions are constructed, along with solitary waves. 
  Reference    Z. Naturforsch. 52a, 295—296 (1997); received June 27 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0295_n.pdf 
 Identifier    ZNA-1997-52a-0295_n 
 Volume    52 
57Author    Barbara Kirchner, Hanspeter Huber, Gerold Steinebrunner, Helmut Dreizler, Jens-Uwe Grabow, Ilona MerkeRequires cookie*
 Title    ab initio Calculation of 33 S Quadrupole Coupling Constants. Reanalysis of the 33 S Hyperfine Structure in the Rotational Spectrum of Thiirane  
 Abstract    We present quantum chemical calculations on the MP4(SDQ) level with basis sets of high local quality to determine the nuclear quadrupole coupling tensor of S in a series of molecules, which were investigated up to now by microwave spectroscopy. The analysis of the nuclear quadrupole coupling in the rotational spectra provided experimental information on the tensors. As an example for such an analysis, improved values for thiirane, C 2 H 4 33 S, are given: i aa = — 32.9425(78) MHz, Xbb = -16.402(14) MHz, * cc = 49.345(14) MHz. 
  Reference    Z. Naturforsch. 52a, 297—305 (1997); received January 12 1997 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0297.pdf 
 Identifier    ZNA-1997-52a-0297 
 Volume    52 
58Author    A. Kuhnen, W. Müller-', M. Warmuth, Prager, O. Mündt, M. Reti, G. BeckerRequires cookie*
 Title    Rotational Tunnelling in Methyl Metal Compounds X 2 (CH 3 ) 4 with X = As, Sb, Bi  
 Abstract    Rotational excitations of methyl groups attached to metal atoms of the fifth main group have been investigated in X 2 (CH 3) 4 crystals with X = As, Sb, Bi by nuclear magnetic resonance (NMR) relaxation measurements and inelastic neutron scattering (INS). CH 3 rotation has been found to be rather weakly hindered (activation energies between 1.7 kJ/mol and 5.8 kJ/mol) so that quantum effects are important to describe the results. Tunnel splittings between 0.1 peV and 23 peV have been observed. Non-equivalent methyl groups in tetramethyldistibane and tetramethyldibismuthane have been identified by both INS and NMR. A consistent description of the T t data is possible by Haupt's equation. The rotational potentials could be derived and relations to the crystal structure have been discussed. 
  Reference    Z. Naturforsch. 52a, 306—316 (1997); received January 21 1997 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0306.pdf 
 Identifier    ZNA-1997-52a-0306 
 Volume    52 
59Author    Ralf Schmidt, Christian Gebauer, Olaf Klein, Wolfhart SeidelRequires cookie*
 Title    Anisotropie Interaction Potentials for He-Pyrrole, He-Furane and He-Thiophene from total Differential Cross Section Measurements  
 Abstract    Differential cross section measurements are reported for scattering of an improved He-atomic beam by crossed beams of Pyrrole, Furane and Thiophene. The damping of the DCS diffraction oscillations is used to extract reliable anisotropic intermolecular potentials, applying the infinite order sudden approximation (IOSA). 
  Reference    Z. Naturforsch. 52a, 317—322 (1997); received September 19 1996 
  Published    1997 
  Keywords    Molecular Beams, Helium, Interaction Potentials, Aromaticity, Heterocyclic Compounds 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0317.pdf 
 Identifier    ZNA-1997-52a-0317 
 Volume    52 
60Author    M. Bode, B. D. Mosel, W. Müller-WarmuthRequires cookie*
 Title    EPR of Gd 3+ in Sulfate Host Crystals of Low Symmetry  
 Abstract    Electron paramagnetic resonance (EPR) spectra of trivalent gadolinium have been investigated in orthorhombic sulfate host crystals MeS0 4 with Me = Sr, Ba, Cd, Hg, Pb and K 2 S0 4 . Because of the low symmetry of the host crystals and the spin quantum number 7/2, complex spectra for several orientations of the magnetic field containing a large number of individual lines had to be analyzed. The spin Hamiltonian parameters have been rigorously determined from the rotational diagrams. Gd 3+ has been found to substitute, first of all, for the monoclinic sites of the host metal ion with charge compensation at larger distances. To a small extent, charge compensation in the vicinity has also been observed, arising from additional centres and spectra with lower intensities. Correlations between EPR spectra and crystal structure are reflected in the values of the zero field splitting parameters. 
  Reference    Z. Naturforsch. 52a, 323—330 (1997); received December 16 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0323.pdf 
 Identifier    ZNA-1997-52a-0323 
 Volume    52 
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