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1992[X]
81Author    George MaroulisRequires cookie*
 Title    On the Electric Multipole Moments of Carbon Monoxide  
 Abstract    The electric dipole, quadrupole, octopole and hexadecapole moment of carbon monoxide has been obtained from finite-field SCF and Moeller-Plesset perturbation theory calculations. The resulting values for the octopole and hexadecapole moments of CO(X 1 r +) are 3.59 eal and — 9.01 ea.Q, respectively. 
  Reference    Z. Naturforsch. 47a, 480—484 (1992); received October 11 1991 
  Published    1992 
  Keywords    Carbon monoxide, Electric moments, Octopole moment, Hexadecapole moment 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0480.pdf 
 Identifier    ZNA-1992-47a-0480 
 Volume    47 
82Author    Toshiyuki Takamuku, Mikito Ihara, Toshio Yamaguchi, Hisanobu WakitaRequires cookie*
 Title    Raman Spectroscopic and X-ray Diffraction Studies on Concentrated Aqueous Zinc (II) Bromide Solution at High Temperatures  
 Abstract    Raman and X-ray scattering experiments have been performed on an aqueous zinc (II) bromide solution with molar ratio [H20]/[ZnBr2] = 10 at 25 to 140 °C. The intensity of the totally symmetric Zn-Br stretching vibration (v^ for the dibromozinc(II) complex increased with increasing temper-ature while that for the tetrabromo complex decreased. A broad band assigned to the symmetric Zn-O stretching vibration (vj for the aqua zinc (I I) ion decreased in intensity with increasing temperature. The X-ray diffraction data revealed that the average number of the Zn-Br interactions within the zinc (II) bromo complexes does not change with temperature, whereas the number of Br • • • Br nonbonding interactions within the complexes decreases from 1.8 at 25 °C to 1.5 at 100 °C. From both Raman and X-ray data it is concluded that with increasing temperature the dibromo species is favored, whereas the tetrabromo and aqua zinc(II) species are unstable in the solution. The analysis of the X-ray diffraction data has shown that the mean Zn-Br bond length within the zinc (II) bromo complexes shortens gradually with increasing temperature, accompanied with an increase in the interligand Br • • • Br distance. This finding suggests that the Br-Zn-Br bond angle increases with decreasing Zn-Br distance for the lower zinc(II) bromo complexes. The equilibrium shift of the zinc (II) bromo complexes with temperature is discussed on the basis of ion-ion, ion-water, and water-water interactions. 
  Reference    Z. Naturforsch. 47a, 485—492 (1992); received November 27 1991 
  Published    1992 
  Keywords    Raman spectroscopy, X-ray diffraction, Zinc(II)bromide, High temperature, Solution structure 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0485.pdf 
 Identifier    ZNA-1992-47a-0485 
 Volume    47 
83Author    Alexander Apelblat, Josef BarthelRequires cookie*
 Title    Conductance Studies of Aqueous Succinic Acid  
 Abstract    Conductance measurements of aqueous solutions of succinic acid and of di-sodium succinate were performed from 278.15 to 308.15 K and the limiting conductances A 0 (1/2 Succ 2-) are reported. The Waiden product is independent of temperature: A 0 (1/2 Succ 2 ~) • >/(T) = 0.503 ± 0.001. The salt con-ductances closely obey the Onsager limiting law. The evaluation of the equilibrium constants for the primary and secondary steps of dissociation, K l and K 2 , and the limiting conductances of the hydrosuccinate ion, (HSucc -), are discussed using the Quint and Viallard conductance equation. 
  Reference    Z. Naturforsch. 47a, 493—498 (1992); received November 2 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0493.pdf 
 Identifier    ZNA-1992-47a-0493 
 Volume    47 
84Author    OttoL. StiefvaterRequires cookie*
 Title    High-Resolution Vibrational Spectra of Furazan II. The B, Fundamental v n at ~ 1175 cm" 1 from Fourier-Transform Infrared Spectroscopy  
 Abstract    The high-resolution FT-IR spectrum of the A-type fundamental vn of furazan (C2H2N20) has been recorded and analysed against the background of rotational information from DRM micro-wave spectroscopy to yield the band origin as = 1175.3377 + 0.0001 cm" 1 . The combined use of microwave (MW) and FT-IR data gives this band origin with a statistical uncertainty of<x = 10" 6 cm -1 and leads to a refinement of the rotational constants of the state v j x = 1 over those derivable from either MW or FT-IR data alone. 
  Reference    Z. Naturforsch. 47a, 499—506 (1992); received October 2 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0499.pdf 
 Identifier    ZNA-1992-47a-0499 
 Volume    47 
85Author    N. Heineking, J. Gripp, H. DreizlerRequires cookie*
 Title    Bromine Spin-Rotation Coupling Constants of Cyclopropylbromide-79 Br and -81 Br  
 Abstract    We reinvestigated the microwave spectrum of cyclopropylbromide with the increased resolution of pulsed microwave Fourier transform spectroscopy. Because of the higher frequency precision, it was possible to determine the spin-rotation coupling constants of bromine. Global fits of rotational constants, quartic centrifugal distortion constants, quadrupole coupling constants including the off-diagonal component x ac > spin-rotation coupling constants simultaneously to almost one hundred hyperfine components for each of the two bromine isotopomers resulted in overall standard deviations of well below 5 kHz. 
  Reference    Z. Naturforsch. 47a, 507—510 (1992); received November 11 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0507.pdf 
 Identifier    ZNA-1992-47a-0507 
 Volume    47 
86Author    N. Heineking, H. DreizlerRequires cookie*
 Title    Nuclear Quadrupole Hyperfine Structure in the Rotational a Q 1 -Subbranch of Deuteroisothiocyanic Acid, DNCS  
 Abstract    The two-nuclei quadrupole hyperfine structure of four a Q!-subbranch transitions of deuteroiso-thiocyanic acid, DNCS, has been resolved and analyzed by use of a waveguide microwave Fourier transform spectrometer. The analysis yielded one previously unknown quadrupole coupling con-stant (X-=Xbb-Xcc) for both nitrogen (x N -= +27.6(11) kHz) and deuterium X-= +175.8(11) kHz). Taking into account the results from earlier work on HNCS, DNCS, HNCO, and DNCO, the orientations of the principal axis systems of the two quadrupole coupling tensors could be calculated. It appears that while the deuterium tensor is aligned to the D-N internuclear axis as expected, the nitrogen tensor is tilted away from the bisector of the DNC angle by 13° towards the NCS chain. 
  Reference    Z. Naturforsch. 47a, 511—514 (1992); received January 2 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0511.pdf 
 Identifier    ZNA-1992-47a-0511 
 Volume    47 
87Author    V. Vill, J. Thiem, P. RollinRequires cookie*
 Title    Flüssigkristalline aromatische Cholesterin-Derivate  
 Abstract    Liquid Crystalline Aromatic Cholesterol Derivates A series of aromatic cholesteryl ethers, esters, phenylcarbonates and benzylcarbonates were prepared and their liquid crystalline properties studied. The occurence of ferroelectric phases as well as properties of cholesteric and blue phases alternate with the number of linking atomes between steroid and atomatic system. 
  Reference    Z. Naturforsch. 47a, 515—520 (1992); eingegangen am 8. November 1991 
  Published    1992 
  Keywords    Cholesterol carbonates, Aromatic cholesterol esters, Ferroelectric liquid crystals 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0515.pdf 
 Identifier    ZNA-1992-47a-0515 
 Volume    47 
88Author    Sn Bakalova, P. Nikolov, E. Stanoeva, V. Ognyanov, M. HaimovaRequires cookie*
 Title    Luminescence Properties and Electronic Structure of Some Quinolizinone and Indolizinone Derivatives  
 Abstract    The absorption and luminescence static and dynamic properties of a group of quinolizinone and indolizinone derivatives in solvents of different polarity at 297 K and 77 K are studied. On the basis of the spectral data and the PPP quantum-chemical results the problem of the main chromophore in these structures is discussed. 
  Reference    Z. Naturforsch. 47a, 521—526 (1992); received October 29 1991 
  Published    1992 
  Keywords    Absorption, Luminescence, Quinolizinones, Indolizinones 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0521.pdf 
 Identifier    ZNA-1992-47a-0521 
 Volume    47 
89Author    Frank Oldag, DieterH. SutterRequires cookie*
 Title    The Rotational Zeeman Effect in Acetone, its 0-Tensor, its Magnetic Susceptibility Anisotropics and its Molecular Electric Quadrupole Moment Tensor; A High Resolution Microwave Fourier Transform Study  
 Abstract    Acetone is a molecule with an intermediate barrier for methyl-top internal rotation, and only molecules in the A^-state of the tunneling motion exhibit a rigid rotor spectrum. For this state we report the results of a rotational Zeeman effect study of acetone in exterior fields up to 20 kGauss (2 Tesla). From an analysis of the observed Zeeman splittings within the asymmetric top approxima-tion the nonzero elements of the g-tensor and the magnetic susceptibility anisotropies were obtained as follows: 
  Reference    Z. Naturforsch. 47a, 527—532 (1992); received December 19 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0527.pdf 
 Identifier    ZNA-1992-47a-0527 
 Volume    47 
90Author    WieslawM. Wiczk, Tadeusz LatowskiRequires cookie*
 Title    The Effect of Temperature on the Fluorescence Quenching of Perylene by Tetrachloromethane in Mixtures with Cyclohexane and Benzene  
 Abstract    The effect of temperature on the fluorescence quenching of perylene has been studied in a variety of two-component mixtures of CC14 with cyclohexane and benzene. Results of these studies are explained in terms of specific interactions between the components of the mixtures. 
  Reference    Z. Naturforsch. 47a, 533—535 (1992); received June 4 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0533.pdf 
 Identifier    ZNA-1992-47a-0533 
 Volume    47 
91Author    RolandR. Netz, Siegfried HessRequires cookie*
 Title    Static and Dynamic Properties of Ferroelectric Liquid Crystals in the Vicinity of a First-Order SmA-SmC* Phase Transition  
 Abstract    A unified theoretical description of static and dynamic properties of ferroelectric liquid crystals in terms of a Landau free energy is presented. The shear deformation tensor is used as principal order parameter. Results for the stationary case for tilt angle variation and dielectric properties are compared with experiments on a compound with a pronounced first-order SmA-SmC* phase transition for various strengths of the applied electric field. 
  Reference    Z. Naturforsch. 47a, 536—542 (1992); received December 24 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0536.pdf 
 Identifier    ZNA-1992-47a-0536 
 Volume    47 
92Author    Tooru Hasebe, Rie Sato, Kazuko Tanaka, Reita TamamushiRequires cookie*
 Title    Stability of the Liquid State of Concentrated Aqueous Solutions of Lithium Salts at Low Temperatures  
 Abstract    The stability of the liquid state of aqueous lithium salt solutions was studied with a modified DTA technique. Aqueous solutions of LiCl and LiSCN in the concentration range 8-14 mol kg -1 , LiBr in the range 8-lOmolkg" 1 maintain their liquid state for at least 50 hours at tempera-tures slightly above their glass transition points. 
  Reference    Z. Naturforsch. 47a, 543—544 (1992); received November 27 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0543_n.pdf 
 Identifier    ZNA-1992-47a-0543_n 
 Volume    47 
93Author    F. WinterbergRequires cookie*
 Title    On the Problem of a Finitistic Quantum Field Theory  
 Abstract    A finitistic quantum field theory, as a model for a unified theory of elementary particles is proposed, making the assumption that all spatial and temporal distances can only assume integer values of a fundamental length and time, for which we have chosen the Planck length and Planck time. To satisfy the condition of causality in its quantized version, the theory must be exactly nonrelativistic, because only then can the concept that points in space are separated by multiples of a fundamental length be formulated in an invariant way. The theory is formulated as a partial finite difference equation, invariant under translations and rotations in space, and translations in time, and can be expressed as a partial differential equation of infinite order. The theory is free of all divergen-cies, has a positive definite metric in Hilbert space and therefore no ghost states. Possessing a fundamental length, chosen to be equal the Planck length, the theory has an inbuilt cut-off at the Planck energy. For energies sufficiently below the Planck energy, the theory can be approximated by the previously described Planck aether model, which can be viewed as a superfluid consisting of Planck masses, leading to special relativity as a dynamic symmetry in the asymptotic limit of low energies. 
  Reference    Z. Naturforsch. 47a, 545—553 (1992); received June 151991 revised version received January 101992 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0545.pdf 
 Identifier    ZNA-1992-47a-0545 
 Volume    47 
94Author    B. S. Dandapat, B. P. KumarRequires cookie*
 Title    Onset of Thermosolutal Convection in a Liquid Layer Having Deformable Free Surface -I. Stationary Convection  
 Abstract    The effect of surface deformation on the onset of thermosolutal convection in a horizontal thin layer heated from below and salted from above is examined, using linear stability theory. It is found that two critical Crispation numbers C^ and Cr 2 exist. For Cr 5S C^ the instability mechanism remains unefTected by the deformation of the free surface, whereas for Cr 1 <Cr<Cr 2 the critical Marangoni number (M c) decreases, showing instability due to deformation. If Cr = Cr 2 , M c is obtained for two values of the wave number. When Cr>Cr 2 , M c decreases as the wave number tends to zero. Further, the effect of the Marangoni number, Biot number, Bond number etc. on the stability characteristics of the problem is discussed. 
  Reference    Z. Naturforsch. 47a, 554—560 (1992); received September 4 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0554.pdf 
 Identifier    ZNA-1992-47a-0554 
 Volume    47 
95Author    B. S. Dandapat, B. P. KumarRequires cookie*
 Title    Onset of Thermosolutal Convection in a Liquid Layer Having Deformable Free Surface -II. Overstability  
 Abstract    The onset of thermosolutal convection driven by a temperature and concentration dependent surface tension is investigated for a thin layer of fluid having a deformable free surface. It is shown that there exist two Crispation numbers (Cr) for oscillatory modes of instability. It is further shown that Cr and the frequency of the oscillatory mode are strongly coupled for large values of Cr. It is found that Cr destabilizes the system for both cases, salted from below and salted from above. 
  Reference    Z. Naturforsch. 47a, 561—564 (1992); received January 10 1992 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0561.pdf 
 Identifier    ZNA-1992-47a-0561 
 Volume    47 
96Author    A. Chrzanowska, K. SokalskiRequires cookie*
 Title    Static and Hydrodynamic Properties of Nematic Liquid Crystals  
 Abstract    The static properties of nematic liquid crystals are summarized. The mean field potential emerging from the static distribution function has been used to the hydrodynamic theory. Rotational viscosity coefficients have been investigated. The Parodi relation has been shown to be completely satisfied. Static and hydrodynamic properties have been predicted on the basis of one intermolecular poten-tial. 
  Reference    Z. Naturforsch. 47a, 565—572 (1992); received January 8 1992 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0565.pdf 
 Identifier    ZNA-1992-47a-0565 
 Volume    47 
97Author    H. Krause, D. H. SutterRequires cookie*
 Title    E H-N = CH-C = N +0 Z H-N = CH-C = N  
 Abstract    The 14 N hyperfine multiplets of low-7 rotational transitions of the E and Z isomers of HN = CH — C = N, produced by flash pyrolysis from (CH 3) 2 N —C = N as precursor, were observed and analysed. The quadrupole coupling constants determined are (c-axis perpendicular to the molecular plane): , X aa /MHz XJUWz XJUHz E H — N = CH — C = N -4. The observed hfs multiplets were predicted with reasonable accuracy from RHF/6-311G** field gradients, once the latter had been scaled appropriately to compensate partly for the typical errors in the RHF-wave functions. The hitherto unmeasured 14 N hyperfine multiplets of the related pyruvonitriles, H —N = C(CH 3) —C = N, are predicted. 
  Reference    Z. Naturforsch. 47a, 573—582 (1992); received December 17 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0573.pdf 
 Identifier    ZNA-1992-47a-0573 
 Volume    47 
98Author    Vytautas Balevicius, Norbert Weiden, Alarich WeissRequires cookie*
 Title    *H and 2 H NMR Studies of Mixtures 2,6-Lutidine/Water Near the Lower Critical Solution Point  
 Abstract    Deuteron spin-lattice relaxation time (TJ measurements of binary mixtures 2,6-lutidine/D 2 0 have been done near the lower critical solution point (T c L), e = (T — T g L)/T c 10~ 5 . Singularities are observed at T c L . The changes in the slope of Ti (2 H) =/(T) can be interpreted as due to the effect of concentration changes on T y and simultaneously strong overlaping of 2 H NMR signals from coexisting phases. In the two-phase region, ca. 2°C above T c L two D 2 0 signals with very strong temperature evolution have been detected. Similar doubling of 2,6-lutidine 'H NMR signals has been observed already at T — T c L ^ 1 °C. It is shown that the two signals arise from the nuclei in two coexisting phases; they are not due to pecularities of hydrogen bond. The difference between chemical shifts of both D 2 0 signals ö' — ö" possess the property of an order parameter, i.e. ö' — (5"~ e ß with 0 = 0.336 ±0.030. 
  Reference    Z. Naturforsch. 47a, 583—587 (1992); received December 28 1991 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0583.pdf 
 Identifier    ZNA-1992-47a-0583 
 Volume    47 
99Author    H. Harder, A. G. Lesarri, J. L. Alonso, H. Dreizler, J. C. LópezRequires cookie*
 Title    Determination of the Ring-Inversion Barrier in y-Thiobutyrolactone by Microwave Fourier Transform Spectroscopy  
 Abstract    The microwave spectrum of y-thiobutyrolactone has been reinvestigated using microwave Fourier transform spectroscopy. The /i c rotation inversion transitions have been found to be splitted for the first excited state of the vibration at ~ 250 cm -1 . An inversion splitting of 0.014 MHz has been measured directly from these transitions. These splittings indicate that the vibration is related to a double minimum potential function describing two ring-twisted conformations connected by inver-sion. A one-dimensional reduced potential function has been derived for this vibration and gives a barrier to ring inversion of 1380± 350 cm" \ 
  Reference    Z. Naturforsch. 47a, 588—590 (1992); received January 20 1992 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0588.pdf 
 Identifier    ZNA-1992-47a-0588 
 Volume    47 
100Author    G. Peters, J. Skowronek, W. PreetzRequires cookie*
 Title    Preparation of Octabromoditechnetate(III,II), ITc 2 Br 8 ] 3 and the Vibronic Structure of the ö Ö* Transition  
 Abstract    The dinstinct vibronic structure of the S -* ö* transition of Cs 3 [Tc 2 Br 8 ] with its mixed valence is well resolved at 6 K. The electronic origin at about 5970 cm" 1 is split into four components, each giving rise to progressions entirely assignable in terms of n and n v x + v 2 up to n = 9, utilizing the totally symmetric stretching modes VJ(TcTc) and v 2 (TcBr) exclusively. 
  Reference    Z. Naturforsch. 47a, 591—594 (1992); received January 31 1992 
  Published    1992 
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 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0591.pdf 
 Identifier    ZNA-1992-47a-0591 
 Volume    47 
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