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991.
Absorption spectra arising from the interaction between various aromatic hydrocarbons and aliphatic amines have been newly observed in the ultraviolet region by the technique of adsorption, and interpreted as being due to transitions to the charge-transfer Franck-Condon states which may correspond electronically to the fluorescent charge-transfer states observed recently in solutions. No charge-transfer fluorescence was observed in the present system. The formation of the fluorescent charge-transfer states seems to be prevented because of the rigid spatial configurations between adsorbed molecules.  相似文献   
992.
NaHC2O4 · H2O crystallizes in space group P 1 with a0 = 6,51, b0 = 6,66, c0 = 5,70 Å, α0 = 95,0°, β0 = 109,8°, γ0 = 74,9° and Z = 2. The structure was solved by direct methods. The refinement was carried out with 679 reflections to R1 = 7,7%. The angle between the O? C? O planes is 12,6°.  相似文献   
993.
Conclusions The authors obtained perfluoroisobutenyl isothiocyanate by reacting perfluoroisobutylene with potassium thiocyanate, and studied some of its properties.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1176–1178, May, 1969.  相似文献   
994.
Modern activation analysis requires the application of efficient data processing for the evaluation of theγ-spectra of samples containing several radionuclides, especially if preceding radiochemical separations are to be largely or completely eliminated. The essential aspects of two programs for quantitative determinations and qualitative identifications are described. These programs are based on the least squares analysis of the total spectrum and the search, arrangement and processing of the photopeaks. With respect to their details the programs are adapted for application on the computer IBM-360/75.  相似文献   
995.
The neutron irradiated potassium hexacyanoferrate(III) solutions were analyzed for Fe(CN)64?, Fe(CN)63?, and Prussian blue. The retention values (1.1%) were constant throughout the pH and concentration ranges studied, and did not change with the length of irradiation. The complex behavior of the radiochemical yield of the Fe(CN)64? and Prussian blue was attributed to the competition of the various reactions involved in the irradiation.  相似文献   
996.
The mass spectra of five diazaphenanthrenes formed by photochemical cyclodehydrogenation of styryl diazines are investigated. It is shown that fragmentation of these compounds starts almost exclusively at the heterocyclic part of the molecule and proceeds by competitive α-cleavage. From the intensity ratios of the ions [M ? H˙]+, [M ? HCN]+˙, [M ? N2]+˙ and [M ? 2 HCN]+˙ generated in this way, each isomer can unequivocally be identified.  相似文献   
997.
998.
Li2SnO3 crystallises monoclinic, C, with a = 5.295, b = 9.184, c = 10.032 Å and β = 100.13°; Z = 8. The positions of Sn were obtained from PATTERSON maps and the positions of O and Li by FOURIER difference method. Parameters were refined by least squares-method [1462 reflexes (h 01)–(h 71); R = 10.5%]. The average distances of Li? O are 2.07 Å, and 2.20 Å for Sn? O. The Li2SnO3 structure can be derived from the NaCl type: in a cubic closest packing of oxygen 2/3 of the octahedral holes are occupied by lithium and 1/3 by tin.  相似文献   
999.
1000.
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