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31.
Conclusions We have studied the temperature dependence of the NQR parameters of123Sb and81Br in the range 77–360 K for the complexes of MSbBrF3 (M=Na, Cs, NH4) and Cs3Sb2Br9. We have established the temperature regions for which piezoelectric properties appear in the crystal hydrate NaSbBrF3.H2O, and in the compounds MSbBrF3 (M=Na, NH4) and Cs3Sb2Br9 anomalous changes appear in the dependences of the quadrupole coupling constant, the asymmetry parameter of the electric field gradient for the antimony atoms and the resonance frequency of the bromine atoms.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1501–1504, July, 1987.  相似文献   
32.
The fragmentation of different alkyl(aryl) substituted piperideines [tetrahydro-pyridines] was studied by analyzing high-resolution mass spectra and DADI [Direct Analysis of Daughter Ions] spectra. It was shown that the retrodiene decomposition of the ring is suppressed by competing processes of elimination of ring substitutents. The nature of the substituents and their mutual disposition on the ring have a substantial influence on the extent of their cleavage from the ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 795–800, June, 1988.  相似文献   
33.
Combining ideas of convolution due to Rankin with spectral considerations of Selberg, the author proposes a new approach to obtaining mean values for certain number-theoretic functions f(n). This approach is illustrated for the examples of functions f(n)=(Mn2+N),(n)(Mn+N), where (n) is the number of divisors of n.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 76, pp. 159–166, 1978.  相似文献   
34.
    
By the XPS method it has been shown that in the catalysts obtained by interacting W(-C4H7)4 with SiO2 several oxidation states of the supported tungsten are realized together with a higher coverage of the silica surface with tungsten compounds, as compared with the catalysts prepared by impregnation of SiO2 with an aqueous solution of (NH4)2 WO4.
, , W(-C4H7)4 SiO2, , , SiO2 (NH4)2 WO4.
  相似文献   
35.
    
The influence of preparation and treatment conditions on the catalytic activity in propylene disproportionation has been studied on catalysts prepared by interaction of W(-C4H7)4 with SiO2. The influence of the prehydration temperature of silica gel and the temperature of the treatment of the catalyst with hydrogen has been found to be appreciable. Comparison between the activity of the catalysts and the average oxidation state of tungsten ions suggests that the oxidation state of tungsten ions in the active catalyst component is +4.
, W(-C4H7)4 SiO2 . . , , 4.
  相似文献   
36.
A new method of production of one of the most widely used isotopes in nuclear medicine, 177Lu, with high chemical purity was developed; this method includes irradiation of the HfO2 target with bremsstrahlung photons. The irradiated target was dissolved in HF and then diluted and placed onto a column filled with LN resin. Quantitative sorption of 177Lu could be observed during this process. The column later was rinsed with the mixture of 0.1 M HF and 1 M HNO3 and then 2 M HNO3 to remove impurities. Quantitative desorption of 177Lu was achieved by using 6 M HNO3. The developed method of 177Lu production ensures high purification of this isotope from macroquantities of hafnium and zirconium and radioactive impurities of carrier-free yttrium. The content of 177mLu in 177Lu in photonuclear production was determined. Due to high chemical and radionuclide purity, 177Lu obtained by the developed method can be used in nuclear medicine.  相似文献   
37.
Radiation-induced accumulation and annealing processes of radiation defects with level Ec–0,22 eV in silicon of various perfection are analysed and it is concluded that they consist of oxygen and two vacancies (oxygen-divacancy complex).  相似文献   
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