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1994[X]
101Author    Noriaki Okubo, Yoshihito AbeRequires cookie*
 Title    35C1 Nuclear Quadrupole Relaxation in Antimony Trichloride  
 Abstract    The 35C1 NQR frequency and spin-lattice relaxation time in SbCl3 have been measured between 10 K and the melting point. The relaxation at low temperatures is attributed to the Raman process. A Debye temperature of 141 K and covalencies 0.390 and 0.356 are obtained. The latter values correspond well to those obtained from the NQR frequencies. For the relaxation above 200 K two more mechanisms are considered. 
  Reference    Z. Naturforsch. 49a, 680—686 (1994); received March 14 1994 
  Published    1994 
  Keywords    Antimony trichloride, Nuclear quadrupole relaxation, Raman process, Debye temper­ ature, Covalency 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0680.pdf 
 Identifier    ZNA-1994-49a-0680 
 Volume    49 
102Author    A. M. Raevsky, A. G. Gukalova, G. K. SeminRequires cookie*
 Title    Nuclear Quadrupole Resonance of Antimony in L^SbgO j 2 Crystals  
 Abstract    Complete 121,123Sb NQR spectra of crystalline rate earth antimonites Ln3Sb50 12 (Ln = La, Nd, Er, Lu) were recorded at 77 K. The quadrupole coupling constants and asymmetry parameters of the electric field gradient were measured. A "lanthanide compression" effect on the antimony NQR was observed. Using relations found for the antimonites under study, the Sb spectral parameters of other lanthanide compounds can be predicted. 
  Reference    Z. Naturforsch. 49a, 687—689 (1994); received February 16 1994 
  Published    1994 
  Keywords    NQR, Rare earth antimonites, 121, 123Sb, " Lanthanide compression" 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0687.pdf 
 Identifier    ZNA-1994-49a-0687 
 Volume    49 
103Author    HaruakiM. Atsuura, Isao OkadaRequires cookie*
 Title    Internal Cation Mobilities in Molten (Ca,Ba)Cl2  
 Abstract    Internal cation mobility ratios in molten (Ca, Ba)Cl2 have been measured by the Klemm method for xBa (mole fraction of barium chloride) = 0.25 -0.51 at 973 K and xBa = 0 -0.61 at 1073 K. From these and available data on the densities and conductivities the internal cation mobilities b have been calculated, assuming additivity of the molar volume. Although bCa in pure CaCl2 is greater than bBa in pure BaCl2, bCa is smaller than bBa in all the investigated mixtures at the respective temperatures* With increasing molar volume at constant temperature both bCa and bBa decrease. Since the profile of the isotherms is similar to that for the binary monovalent chloride systems so far studied, monoatomic ionic species are assumed to carry the current also in the alkaline earth chloride melts. 
  Reference    Z. Naturforsch. 49a, 690—694 (1994); received April 5 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0690.pdf 
 Identifier    ZNA-1994-49a-0690 
 Volume    49 
104Author    B.Thimme Gowda, Alarich WeissRequires cookie*
 Title    The Bond N -C l. A Spectroscopic (35C1-NQR, IR) Investigation  
 Abstract    Chlorine bound to nitrogen is an interesting oxidizing agent in aqueous, partial aqueous and non-aqueous media. One can assume that the oxidizing action of the chlorine depends on the polarization of the Cl atom in the bond N -C l which will depend on the electron distribution in the ligands R and R" of the configuration R -N C 1 -C O -R ". 17 compounds were synthesized with R = substituted phenyl radical C6H 5-yXy, X = C1, N 0 2, R " = C H 2C1. The 35C1 NQR frequencies are observed in the range 52 to 54 MHz (T = 77 K) for the C1(N\ 34 to 37 MHz for the phenyl chlorines and the CH2C1 group. Their temperature dependence was followed up to 300 K. Therefrom the assignment of the resonance to certain Cl-atoms in the molecules is possible. Generally, the sub­ stitution of a negative substituent X (Cl, N 0 2) in the phenyl ring raises the resonance frequencies; the influence of the C H 2C1 group on the N -C l bond is weak. Strong is the influence of the carbonyl group on the N -C l bond. The IR group frequencies v(C = 0) are found in the range 1680 < v (C = 0)/c m -1 < 1717, shifted up by < 20 cm -1 compared to the corresponding acetamide R —NH —CO —R". Influence of the phenyl ring substitution on v (C = 0) does not follow a simple law of inductive effect. Also a correlation between the vibration frequencies of the N -C l group and the phenyl group substitution is not found. 
  Reference    Z. Naturforsch. 49a, 695—702 (1994); received March 14 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0695.pdf 
 Identifier    ZNA-1994-49a-0695 
 Volume    49 
105Author    M. Krüger, H. Dreizler, D. Lentz, D. PreugschatRequires cookie*
 Title    Synthesis and Microwave Spectroscopic Study of Fluorinated Methyl Isocyanides  
 Abstract    Difluoromethyl isocyanide has been generated by flash vacuum pyrolysis of pentacarbonyl (di-fluoromethyl isocyanide) chromium at 240 °C. Spectroscopic studies revealed the presence of several major and minor impurities like HCN, H C C -C N and H C C -N C . The pyrolysis of pentacar­ bonyl (fluoromethyl isocyanide)chromium did not lead to the observation of free fluoromethyl isocyanide. The rotational spectrum of difluoromethyl isocyanide has been recorded with a conven­ tional continuous wave Stark spectrometer and a molecular beam Fourier transform microwave spectrometer resulting in A = 10.110841 (42), B = 4.550914 (19), C = 3.343550 (19) GHz, Dj = 0.41(13), D'jk = 26.72(36), D'K= — 21.3 (18) kHz. The dipole moment components //" = 1.46(1), Hc= 1.83 (1) and /xtotai 2-34 (1) D were obtained from the second order Stark effect. The 14N nuclear quadrupole hyperfine structure in the rotational spectrum of CHF2-N C has been resolved and the 14N nuclear quadrupole coupling constants xaa— 599.0 (10), Xbb~ —406.5 (14), ^cc= —192.6 (14) kHz have been obtained. 
  Reference    Z. Naturforsch. 49a, 703—708 (1994); received April 7 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0703.pdf 
 Identifier    ZNA-1994-49a-0703 
 Volume    49 
106Author    J. Zaleski, R. JakubasRequires cookie*
 Title    The Dielectric and Dilatometric Single Crystal Studies of Phase Transitions in a New Member of Family of Halogenoantimonates(III) [C(NH2)3l2SbCl5* [C(NH2)3]C1  
 Abstract    The results of dielectric, dilatometric and DSC studies on a new member of the family of alkylammonium halogenoantimonates ([(C(NH2)3]2SbCl5 • [(C(NH2)3]C1) are presented. This com­ pound undergoes three phase transitions at 146 K, 162 K, and 366 K. The two low temperature transitions are suggested to be of the displacive type and the high temperature one of the order-dis-order type. The character of temperature changes of the electric permittivity at the lowest temper­ ature transition suggest a polar phase below the transition temperature. 
  Reference    Z. Naturforsch. 49a, 709—713 (1994); received March 23 1994 
  Published    1994 
  Keywords    Phase transitions, Dielectric, Dilatometric, Halogenoantimonate, Guanidinium 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0709.pdf 
 Identifier    ZNA-1994-49a-0709 
 Volume    49 
107Author    Josef Esser, Jörg Fleischhauer, Herbert Frauenrath1, Christoph Jansen, Bernd Kramer, Jan RunsinkRequires cookie*
 Title    Semiempirische Rechnungen zur Bestimmung der Konformation des 4,5-Dihydro-l,3-dioxepins und seines 2-Methyl-Derivats  
 Abstract    Semiempirical Calculations for the Determination o f the Conformation o f 4,5-dihydro-1,3-dioxepine and its 2-methyl derivative The possible conformations of the title compounds have been studied with the semiempirical methods MNDO and AMI. In the local minima, the vibration frequencies have been calculated to get the free enthalpy of each conformer and its equilibrium concentration. The energy minimized structures and the calculated thermodynamical values are compared with experimental results. From our investigations we conclude that the chair conformation is preferred. In the case of the methyl derivative, the substituent favours the equatorial position. 
  Reference    Z. Naturforsch. 49a, 714—718 (1994); received May 2 1994 
  Published    1994 
  Keywords    MNDO, AMI, Free enthalpy, Equilibrium concentration 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0714.pdf 
 Identifier    ZNA-1994-49a-0714 
 Volume    49 
108Author    Tetsuo MorikawaRequires cookie*
 Title    Structural Features for Non-Existence of Conjugated Patterns for Carbocyclic and Heterocyclic Compounds  
 Abstract    At least one polygonal arc (a' a a'), where (a') and (a) denote unconjugated and conjugated vertices (connected with two vertices), respectively, is involved implicitly and/or explicitly in a skeleton of carbocyclic and heterocyclic compounds with no side-chains, if the number of conjugated vertices is even, and if there is no conjugated structure. This case is discussed in detail. 
  Reference    Z. Naturforsch. 49a, 719—722 (1994); received March 15 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0719.pdf 
 Identifier    ZNA-1994-49a-0719 
 Volume    49 
109Author    Hiroyuki Ishida, Yoshihiro Kubozono, Setsuo Kashino, Ryuichi IkedaRequires cookie*
 Title    Crystal Structure of Trimethylammonium Perchlorate in Three Solid Phases Including the Ionic Plastic Phase Obtainable above 480 K  
 Abstract    The crystal structures of (CH3)3NHC104 in three solid phases were studied by X-ray diffraction techniques. X-ray powder patterns taken at ca. 500 and 445 K revealed that the plastic phase (Phase I) attainable above 480 K crystallizes in a CsCl-type cubic structure with a = 5.845 (1) A, Z = 1, V = 199.7 (2) Ä3, and Dx = 1.327 gem -3, while Phase II, stable between 480 and 396 K, forms a tetragonal structure with a = 9.912 (4), c = 7.01 (2) Ä, Z = 4, V = 689 (3) A3, and Dx = 1.54 gem -3. The room temperature phase (Phase III) was studied by single crystal X-ray diffraction and found to form a monoclinic lattice with space group P2X , a = 5.749(1), b = 8.670(1), c = 7.5585 (9) A, ß = 102.66 (1)°, Z = 2, V = 367.6 (2) A , and Dx= 1.441 g em -3. Thermal measurements, differential thermal analysis and differential scanning calorimetry, were carried out on these solid phases, and the obtained results were compared with those observed for (CH3)3NHBF4. 
  Reference    Z. Naturforsch. 49a, 723—726 (1994); received March 12 1994 
  Published    1994 
  Keywords    Crystal structure, X-ray diffraction, Thermal measurements, Ionic plastic phase 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0723.pdf 
 Identifier    ZNA-1994-49a-0723 
 Volume    49 
110Author    Yoshihiro Kubozono, Akiko Hirano, Hironobu Maeda, Setsuo Kashino, Shuichi Emura, Hiroyuki IshidaRequires cookie*
 Title    An EX AFS Investigation of Local Structure around Rb + in Aqueous Solution  
 Abstract    EXAFS spectra have been measured in order to elucidate the local structure around Rb+ in aqueous solution. It has been found that the Rb+ is surrounded by ca. six O atoms of H 20 molecules. The R b -O distance was determined to be 2.90 (3) Ä. The coordination number and R b -O distance compare well with those of the other alkaline metal ions estimated by X-ray diffraction. 
  Reference    Z. Naturforsch. 49a, 727—729 (1994); received March 28 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0727.pdf 
 Identifier    ZNA-1994-49a-0727 
 Volume    49 
111Author    W. Hack, M. WagnerRequires cookie*
 Title    A Molecular Source of CF2(X) at Room Temperature  
 Abstract    In the molecular system of F2 and C 30 2 a fast formation of CF2 (X) was detected directly via LIF. The CF2 (X) produc­ tion mechanism could be a single step process but also how­ ever a chain reaction via F atoms. 
  Reference    Z. Naturforsch. 49a, 730 (1994); received April 25 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0730_n.pdf 
 Identifier    ZNA-1994-49a-0730_n 
 Volume    49 
112Author    Stefan Querbach, Martin KretzschmarRequires cookie*
 Title    Non-Strange Baryon Resonances in the Isgur-Karl Model Including the 7V=3 Oscillator Shell  
 Abstract    The nonrelativistic constituent quark model for excited baryon states in the version proposed by Isgur and Karl is extended toward higher energies by including all states containing up to three oscillator excitation quanta. At high energies baryon resonances with spins up to 9/2 become accessible. At all energies and in particular for lower spins strong configuration mixing is obtained. Model predictions are compared to the empirical resonance energies derived in the Karlsruhe-Helsinki pion nucleon phase shift analysis. A search is made for parameter sets that apply simulta­ neously to the positive parity and the negative parity states. Numerical results are presented and discussed in relation to experimental data and to other theoretical works. 
  Reference    Z. Naturforsch. 49a, 733—745 (1994); received December 8 1993 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0733.pdf 
 Identifier    ZNA-1994-49a-0733 
 Volume    49 
113Author    H. PreußRequires cookie*
 Title    Die Lösung der Schrödinger-Gleichung als eindimensionales Problem. I. Der Formalismus  
 Abstract    Solving the Schrödinger-equation as a One-dimensional Problem. I. The Formalism In this article a new method for solving the multi-dimensional Schrödinger-equation for electrons and nuclei will be discussed. It is shown by application of integral transformations and by use of space-filling curves how the multi-dimensional Schrödinger-equation can be replaced by an one­ dimensional integral equation. Furthermore the problems of accuracy arising due to the use of this approximative treatment are pointed out. The presented method can be stated without the Born-Oppenheimer approximation and the application of determinants for fitting the wave function is discussed in a new one-dimensional point of view. 
  Reference    Z. Naturforsch. 49a, 746—750 (1994); received May 2 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0746.pdf 
 Identifier    ZNA-1994-49a-0746 
 Volume    49 
114Author    W.-H SteebRequires cookie*
 Title    Extended Lorenz Models and Time Dependent First Integrals  
 Abstract    We show how computer algebra can be used to find time dependent first integrals of dissipative dynam ical systems. Extended Lorenz models are studied as examples. The Lorenz model [1] and extended versions thereof are autonomous systems of first-order differ­ ential equations du dt = V (u), (1) where u = (uu u2, ...,un)T. The functions Vj are poly­ 
  Reference    Z. Naturforsch. 49a, 751—753 (1994) 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0751.pdf 
 Identifier    ZNA-1994-49a-0751 
 Volume    49 
115Author    M. Yriam, S. De Giam, M. Ario, Giam Biagi, Jorge HerreraRequires cookie*
 Title    The Three-Center, / -E l e c t r o n Chemical Bond  
 Abstract    A definition is proposed for the number o f electrons x involved in a three-center bond, based upon the corresponding two-center bond indices. The number o f electrons is fractionary, ranging from about 1 to somewhat more than 4 in the systems considered here. I t is seen that the sign o f the three-center index does not depend on % ■ 
  Reference    Z. Naturforsch. 49a, 754—758 (1994) 
  Published    1994 
  Keywords    Three-center bond, M ulticenter bond indices, Active charge 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0754.pdf 
 Identifier    ZNA-1994-49a-0754 
 Volume    49 
116Author    C. T. Yap, Younan HuaRequires cookie*
 Title    Provenance Study of Famous Chinese Greenware Bodies Using Principal Component Analysis  
 Abstract    This work is based on published analytical data of 69 pieces of Chinese greenware bodies from seven famous wares: Yue, Longquan, Southern Song Guan, Ru, Jun, Yaozhou, and Ge. It is possible to do provenance studies of these wares by the application of principal component analysis using major and minor chemical constituents (Si02, A120 3, Fe20 3, CaO, MgO, K 20 , Na20 , and TiOz). The results show that not only are northern and southern greenwares completely distinct in the raw materials used, but in addition the southern greenwares are reasonably well segreated into groups belonging to Yue ware, Longquan ware (white body), Longquan ware (black body) and Southern Song Guan ware. Our analysis also confirms the production of Ge ware in the Longquan area. 
  Reference    Z. Naturforsch. 49a, 759—766 (1994); received May 16 1994 
  Published    1994 
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 Identifier    ZNA-1994-49a-0759 
 Volume    49 
117Author    M. Manthey, W. PreetzRequires cookie*
 Title    Luminescence Spectra of the Mixed Chloro-Bromo-Osmates(IV), |OsCl"Br6_"l2_, n = 1-5  
 Abstract    The Ti^Ajg) -► r ^ T jg) luminescence spectra of mixed Cs2[OsCl"Br6_ J, n = 1-5, have been measured between 15 800 and 17 000 cm 1 at 10 K. As a host lattice Cs2[TeCl6] has been doped with purely isolated chloro-bromo-osmates(IV), including the geometrical isomers with n = 2, 3, 4. The assignments of the electronic transitions and their extensive vibronic structure are discussed. 
  Reference    Z. Naturforsch. 49a, 767—770 (1994); received May 14 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0767.pdf 
 Identifier    ZNA-1994-49a-0767 
 Volume    49 
118Author    Jürgen Ankele, Joachim Mayer, Peter Lamparter, Siegfried SteebRequires cookie*
 Title      
 Abstract    The structure factor of amorphous germanium was determined using 120 kV electrons, an ß-filter for the elimination of inelastically scattered electrons and a correction procedure for multiple scattering. The structure factor thus obtained is in good accordance to that obtained with X-rays and neutrons, respectively. 
  Reference    Z. Naturforsch. 49a, 771—775 (1994); received June 7 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0771.pdf 
 Identifier    ZNA-1994-49a-0771 
 Volume    49 
119Author    Michael Dey, Jürgen Grotemeyer1, EdwardW. SchlagRequires cookie*
 Title    Pair Formation of Free Nucleobases and Mononucleosides in the Gas Phase  
 Abstract    The formation of neutral bimolecular clusters of unsubstituted nucleobases and mononucleosides in the gas phase has been studied by IR laser desorption of the neutral molecules into a supersonic beam expansion. The complementary nucleobase pairs adenine-thymine and cytosine-guanine of D N A have been found to be formed in preference to non complementary base pairs. Association constants for the formation of the dimers of free nucleobases and nucleosides in the gas phase are calculated from the experimental results. A strong influence due to side groups affecting the dimer formation of the nucleobases is shown. 
  Reference    Z. Naturforsch. 49a, 776—784 (1994); received May 20 1994 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0776.pdf 
 Identifier    ZNA-1994-49a-0776 
 Volume    49 
120Author    K. Fukushima, M. Murofushi, M. Oki, K. Igarashi, J. Mochinaga, Y. IwadateRequires cookie*
 Title    Intraionic Structure of H S 0 4 and Alkali Cation Configuration in Molten N a H S 0 4 and K H S 0 4  
 Abstract    The short range structure of molten N a H S 0 4 (I) and K H S 0 4 (II) was estimated by X-ray diffrac­ tion. The polyatomic anion, H S 0 4 , in both molten salts was found to have a distorted tetrahedral structure in which the bond lengths of S-O and S-OH were 1.45 Ä and 1.53 Ä in (I) and 1.46 Ä and 1.56 Ä in (II), respectively. The coordination number of the N a + or K + around the H S 0 4 was evaluated to be about unity. The semi-empirical molecular orbital calculations by the MNDO-MOPAC method were applied to the determination of the intraionic structure of the H S 0 4 and the bond lengths of S-O and S -O H were computed to be 1.528 Ä and 1.666 Ä, respectively, supporting qualitatively that the H S 0 7 forms a rather distorted tetrahedron. 
  Reference    Z. Naturforsch. 49a, 785—789 (1994); received September 13 1993 
  Published    1994 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0785.pdf 
 Identifier    ZNA-1994-49a-0785 
 Volume    49 
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