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21Author    Takahiro Ueda, Nobuo NakamuraRequires cookie*
 Title    Nature of Hydration Water in (±)-Tris(ethylenediamine)cobalt(III) Chloride Hydrate, (±)-[Co(en) 3 ]Cl 3 -/iH 2 0, as Studied by *H, 2 H, and 17 O Solid State NMR  
 Abstract    The static and dynamics properties of hydration water molecules in (±)-[Co(en) 3 ]Cl 3 were studied by means of 'H, 2 H, and ,7 0 solid state NMR. By 'H pulsed field gradient (PFG) NMR the apparent diffusion coefficient of mobile water through a micropore along the crystalline unique c-axis was found to be 1.0 x 10~ 9 m 2 s -1 . The 2 H NMR spectrum at 141 K consists of two components, one being a Pake doublet corresponding to a quadrupole coupling constant (QCC) of (226 ± 2) kHz and an asymmetry parameter of the electric field gradient 77 of 0.08 ± 0.01, and another being a Gaussian line with a linewidth of 3.5 kHz. The 17 0 NMR spectrum at 300 K also consists of a narrow Gaussian peak and a broad powder pattern with a second order quadrupole effect corresponding to QCC = (6.3 ± 0.5) MHz and 77 = 0.55±0.02. The broad and narrow components are assigned to water molecules accommodated at general 12g positions and special 2a and 2b positions in the trigonal lattice with space group Plcl. From the ratio of the populations at these positions their potential energy difference was estimated to be between (2.7 ±0.1) and (3.5 ± 0.1) kJmol -1 . The 2 H NMR spectrum at room temperature indicates a finite quadrupole interaction which is attributable to the rapid rotation of water molecule about the molecular C 2 -axis. When the water content exceeds 2.7, the QCC is reduced sharply to (5.0 ±0.1) kHz at 285 K, suggesting that there occurs rapid rotation of water and rapid exchange of 2 H between nonequivalent positions. 
  Reference    Z. Naturforsch. 55a, 362—368 (2000); received August 23 1999 
  Published    2000 
  Keywords    (±)-[Co(en) 3 ]Cl 3, Absorbed Water, Molecular Motion, Hydrogen Bond, Quadrupole Interaction 
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 TEI-XML for    default:Reihe_A/55/ZNA-2000-55a-0362.pdf 
 Identifier    ZNA-2000-55a-0362 
 Volume    55 
22Author    Hiroyuki IshidaRequires cookie*
 Title    H NMR Study of Ionic Motions in High Temperature Solid Phases of (CH 3 NH 3 ) 2 ZnCl 4  
 Abstract    The reorientation of the tetrahedral complex anion ZnCl 4 2-and the self-diffusion of the cation in (CH 3 NH3) 2 ZnCl4 were studied by 'H NMR spin-lattice relaxation time ('H T X) experiments. In the second highest-temperature phase, the temperature dependence of *H T X observed at 8.5 MHz could be explained by a magnetic dipolar-electric quadrupolar cross relaxation between 'H and chlorine nuclei, and the activation energy of the anion motion was determined to be 105 kJ mol -1 . In the highest-temperature phase, the activation energy of the self-diffusion of the cation was determined to be 58 kJ mol -1 from the temperature and frequency dependence of 'H T X . 
  Reference    Z. Naturforsch. 55a, 412—114 (2000); received January 8 2000 
  Published    2000 
  Keywords    Nuclear Magnetic Resonance, Molecular Motion, Cross Relaxation, (C^N^^ZnCfj 
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 TEI-XML for    default:Reihe_A/55/ZNA-2000-55a-0412.pdf 
 Identifier    ZNA-2000-55a-0412 
 Volume    55 
23Author    Takashi Fujim, Isao KaetsuRequires cookie*
 Title    Nature of Yeast Cells Immobilized by Radiation Polymerization Activity Dependence on the Molecular Motion of Polymer Carriers  
 Abstract    Higher activity of ethanol production due to higher density of yeast cells, was observed in yeast cells immobilized with artificial polymer carriers of higher molecular motion. These polymer carriers were prepared by radiation-induced polymerization below 0 °C. Yeast cells were im­ mobilized with these carriers by adsorption method during multiplication. Molecular motion of polymer carriers in swollen state was evaluated by the line width of nuclear magnetic resonance spectrum. A possible reason for higher activity was discussed. This study of relation between molecular motion of polymer carriers and activity of yeast cells immobilized with these carriers, is very useful to design the chemical and physical structure of polymer carriers for immobilization of microorganisms. 
  Reference    Z. Naturforsch. 40c, 576 (1985); received December 31 1984/April 30 1985 
  Published    1985 
  Keywords    Yeast Cells, Activity, Molecular Motion, Immobilization by Radiation Polymerization, Polymer Carriers 
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 TEI-XML for    default:Reihe_C/40/ZNC-1985-40c-0576.pdf 
 Identifier    ZNC-1985-40c-0576 
 Volume    40 
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