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31.
T. V. Mezhenkova V. M. Karpov V. E. Platonov 《Russian Journal of Organic Chemistry》2011,47(7):1026-1034
Reactions of perfluorinated 1-phenyl-, 1-(2-ethylphenyl)-, 1-(4-ethylphenyl)-, 1-methyl-2-phenyl-, and 1-ethyl-2-phenyl-1,2-dihydrocyclobutabenzenes
with iodine in antimony pentafluoride at 130°C, followed by hydroysis of the reaction mixture, resulted in the formation of
perfluorinated 2-methyl-, 2-ethyl-2′-methyl-, 4-ethyl-2′-methyl-, 2-ethyl-, and 2-propylbenzophenones via opening of the four-membered
ring in the initial cyclobutabenzene at the C1–C2 bond. The presence of hydrogen fluoride facilitates the process and promotes profound transformations leading to anthracene
derivatives. 相似文献
32.
Perfluoro-1-ethylindane on heating with SbF5 is isomerized to perfluoro-1,1-dimethylindane, perfluoro-,-o-trimethylstyrene, and perfluoro-1,2-dimethylindane. In the presence of SbF5, the latter two products are converted one into the other. In addition, in SbF5 perfluoro-1,2-dimethylindane is defluorinated to perfluoro-2,3-dimethylindene and fluorinated to perfluoro-2,3-dimethyl-4,5,6,7-tetrahydroindene which is further fluorinated to perfluoro-1,2-dimethyl-4,5,6,7-tetrahydroindane and is converted at 200C to perfluoro-1,7-dimethylindane. The latter is also formed on heating perfluoro-,-o-trimethylstyrene with SbF5 at 200C.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 645–652, March, 1990. 相似文献
33.
For the five-coordinated complexes of ferroprotoporphynynn with imidazole, a quantum-chemical analysis of the electronic structure and Mossbauer spectral parameters has been canied out. Peripheral substituents (CH3, Cf13, C2H4COOH) were introduced into the porphynin macrocycle to model the real chemical structure of protopo'phynynn in the heme group of desoxyhemoglobin. The calculations have shown that near the occupation border in the complaes there are MO which are due to the -systems of the CH= CM2 and CH2CH2COOH substituents. The orientalion of the vinyl fragments has a considerable effect on the populations of the Fe d-orbitals and the quadrupole splitting EQ for the5B1 and5B2 terns.Institute of Biophysics, Ministry of Health, Russian Federation. Translated fromZhurnal Strukturmoi Khimii, Vol. 34, No. 5, pp. 90–93, September–October, 1993.Translated by L. Smolina 相似文献
34.
I. V. Karpov I. I. Shagimuratov G. A. Yakimova O. P. Suslova 《Russian Journal of Physical Chemistry B, Focus on Physics》2011,5(3):387-392
The characteristics of total electron content (TEC) variations obtained using the data of middle-latitude stations for receiving GPS satellite signals were studied. An analysis showed that perturbations of diurnal TEC variations during a geomagnetic storm were determined by strengthening of harmonics with periods of 4–5 and 6–8 h. Perturbations in diurnal TEC variations were retained for several days after a geomagnetic storm. An analysis of the frequency and amplitude characteristics of perturbed variations showed that differences between variations at different latitudes could be explained by the propagation of Poincaré planetary waves in an atmospheric wave channel. The atmospheric channel was formed because of increased heating of pole regions during geomagnetic storms. A comparative analysis of observations made at different stations was used to estimate the width of the atmospheric channel and Poincaré wave frequencies and wave vector components. 相似文献
35.
G. V. Golubkov M. I. Manzhelii I. V. Karpov 《Russian Journal of Physical Chemistry B, Focus on Physics》2011,5(3):406-411
Modern concepts of the structure of the ionosphere and dynamics of its perturbations related to geomagnetic and solar activity
perturbations are considered. It is shown that communication and navigation satellite systems depend substantially on the
state of the ionosphere. The role played by Rydberg atoms and molecules of neutral ionospheric plasma components excited in
collisions with electrons in the formation of microwave radiation of the upper atmosphere is discussed. A new physical mechanism
of the delay of satellite signals cased by a cascade of reemissions from Rydberg states over the decimeter range is suggested. 相似文献
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We investigate the applicability of Hegerfeldts arguments on Quantum nonlocality in Quantum Electrodynamics following the work of Prigogine, Pronko, Petrosky, Ordonez and Karpov. We demonstrate the appearance of nonlocal effects at the level of quantum states. We show, however that the expectation values of some observables spread causally. Therefore the measurement of the nonlocality is questionable. We investigate an approach to classical measurement and conclude that the classical measurement cannot detect the acausal effects of the non-locality. 相似文献