Go toArchive
Browse byFacets
Bookbag ( 0 )
'35 C1' in keywords Facet   section ZfN Section A  [X]
Results  4 Items
Sorted by   
Publication Year
2000 (1)
1998 (1)
1992 (1)
1990 (1)
1Author    David Stephenson, JohnA S Smith, St Augustine, Tobago TrinidadRequires cookie*
 Title    Double Resonance Detection Using Zero Field Level Crossing  
 Abstract    Double resonance level crossing detection cannot normally be used to record transitions between the quadrupole Zeeman levels. Neither can it be used if the quadrupole resonance frequency is larger than the proton NMR frequency in high field. A simple variation of the level crossing experiment is demonstrated which allows energy to be efficiently transferred from quadrupole to proton system and hence lead to detection in these two cases. In the case of the quadrupole Zeeman levels it allows transitions between the ±\ levels to be detected in a small magnetic field, allowing measurement of the asymmetry parameter (r\) for spin 3/2 systems. This is demonstrated for the 1X B nucleus in triethanolamine borate. Detection of high frequency quadrupole transitions is demonstrated from which relaxation information is obtained. 
  Reference    Z. Naturforsch. 53a, 301—304 (1998); received October 31 1997 
  Published    1998 
  Keywords    NQR, Asymmetry Parameter, Relaxation, n B, 35 C1 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0301.pdf 
 Identifier    ZNA-1998-53a-0301 
 Volume    53 
2Author    VirendraK. Sharma, Werner Richarz, Surendra Sharma, Alarich WeissRequires cookie*
 Title    A NQR Study of y-alumina Containing Chemisorbed Cl 2  
 Abstract    Cl 2 was adsorbed at 370 and 870 K on commercially available y-alumina, with BET surface area of 180m 2 /g, after dehydration at 850 K. NQR measurements were carried out between 55 and 6 MHz. The sample containing Cl ? chemisorbed at 870 K showed the presence of a set of quite strong NQR signals with frequencies lower than 10.6 MHz, and another set of very weak NQR signals between 18.5 and 13.0 MHz. The stronger signals have been inferred as due to Al and have been assigned to Al in three distinct environments. The values of e 2 Qq/h and ^ determined for the signals are (1) 35.9 MHz, 0.53; (2) 35.7 MHz, 0.74; and (3) 35.3 MHz, 0.0 respectively. These values of e 2 Qq/h are found to be very high as compared to those estimated for 27 A1 at distorted octahedral and tetrahedral sites of the alumina, viz. 3.5 and 4.0 MHz respectively, from MAS-NMR. Therefore, chemisorption causes 27 A1 to exist in the surface region at sites with greater distortion than in the interior of the particles but much smaller than in the case of completely dehydrated samples for which no NQR signals could be observed. The weak signals have been tentatively attributed to 35 C1. The present results demonstrate that the NQR technique can be used in studies of chemically bound species on heterogenous catalysts. 
  Reference    Z. Naturforsch. 45a, 545—549 (1990); received August 22 1989 
  Published    1990 
  Keywords    Nuclear Quadrupole Resonance, Chemisorption, 35 C1, 27 A1, y-Alumina 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/45/ZNA-1990-45a-0545.pdf 
 Identifier    ZNA-1990-45a-0545 
 Volume    45 
3Author    L. A. Zemnukhova, S. I. Kuznetsov, G. A. Fedorishcheva, R. L. DavidovichRequires cookie*
 Title    The Temperature Dependence of 12U23 Sb, 35 C1, 79,81 Br and 127 I NQR Spectra in Complexes Cs 3 Sb 2 X 9 (X = CI, Br, I)  
 Abstract    The 12U23 Sb, 35 C1, 79 81 Br and 127 I NQR Spectra of the complexes Cs 3 Sb 2 X 9 (X = C1, Br, I), prepared from CsX and SbX 3 aqueous solutions, were studied at 77-400 K. Analysis of the^ temperature coeffi-cients of the quadrupole transition frequency (v), quadrupole coupling constant (e 2 Qq zz) and asymme-try parameter of the electric field gradient (q) was carried out. 
  Reference    Z. Naturforsch. 55a, 134—138 (2000); received October 13 1999 
  Published    2000 
  Keywords    Antimony (III), Haloid Complex Compounds, 121J23 Sb, 35 C1, 79 -81 Br, 127 I, NQR Spectra 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/55/ZNA-2000-55a-0134.pdf 
 Identifier    ZNA-2000-55a-0134 
 Volume    55 
4Author    M. Gourdji, L. Guibé, A. Péneau, J. Gallier, B. Toudic, H. CailleauRequires cookie*
 Title    NQR Investigation of the Temperature-Induced Neutral-to-Ionic Phase Transition in the Mixed-Stack Charge-Transfer Complex TTF-CA  
 Abstract    The chlorine-35 NQR has been investigated in the mixed-stack charge-transfer complex tetrathia-fluvalene-chloranil. The neutral-to-ionic (N-I) phase transition is clearly seen on the NQR spectrum. Among several features of the spectra recorded and their counterpart in the sample behaviour, the evidence for the change in the crystal symmetry and the quite likely existence of neutral domains in the ionic phase below the N-I transition temperature are the most striking ones. 
  Reference    Z. Naturforsch. 47a, 257—260 (1992); received August 3 1991 
  Published    1992 
  Keywords    TTF-CA, TINIT, Neutral-to-ionic phase transition, Mixed-stack charge transfer com-plex, NQR, 35 C1 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-0257.pdf 
 Identifier    ZNA-1992-47a-0257 
 Volume    47