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101.
Alexander V. Stepakov Ekatherine A. Popova Liubov V. Stepakova Vitaly M. Boitsov Galina L. Starova Elena V. Grinenko 《Tetrahedron》2010,66(27-28):5262-5269
Imides of arylmaleic acids in the presence of 3,5-dimethyl-1H-pyrazole underwent (4+2) dimerization under heating in chlorobenzene within 24 h to afford 1,2,3,3a,3b,4,5,6,6a,10b-decahydrobenzo[e]pyrrolo[3,4-g]isoindole-1,3,4,6-tetraones in good yields. It was established that during the heating of imides of arylmaleic acid in 2,6-lutidine at 100 °C the (4+2) dimerization products containing a lutidine fragment are obtained. 相似文献
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In the work we studied the substructure of 30KhGSA steel after rolling. A relation has been established between the macrofracture of the specimen and its dislocation substructure. The formation and completion of a fragmented substructure with precipitation of carbides at the junctions of fragments during rolling indicate that the lifetime is close to exhaustion. Annealing that partially or completely destroys the fragmented substructure causes microcracks to collapse and heal, eliminates the microcrack nucleation sites, eliminates trajectories of facilitated microcrack growth, which follow subboundaries, and restores the plasticity of the steel.Tomsk State Architectural and Civil Engineering Academy. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 73–82, August, 1994. 相似文献
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L. G. Sveshnikova V. I. Yakovlev A. N. Turundaevskii V. I. Galkin S. I. Nazarov D. M. Podorozhnyi N. S. Popova T. M. Roganova 《Physics of Atomic Nuclei》2006,69(2):263-271
For the first time, experimental data on 2-to 40-TeV hadronic cascades recorded by a lead ionization calorimeter at the Tien-Shan mountain station of the Lebedev Institute of Physics (Moscow) are compared with the results of a present-day simulation based on the GEANT 3.21 code and performed with allowance for the detection procedure. The conclusion that along-flying component appears in high-energy hadronic cascades was drawn previously on the basis of these data. Some special features of the procedure for recording TeV-range hadrons in the calorimeter are considered. It is shown that the averaged hadronic cascades and various features of single cascades having energies below 10 TeV are simulated adequately by using the QGSJET + FLUKA generators of nuclear interactions, but that they are not described by using the GHEISHA generator at lower energies. Some features of the experimentally observed cascades could not be described for cascade energies above 10 TeV. 相似文献
110.
Mario Waser Yulita Popova Christian W. Klampfl Heinz Falk 《Monatshefte für Chemie / Chemical Monthly》2005,52(2):1791-1797
Investigating the properties of similar but regioselectively differently substituted hypericin derivatives, 9,12-dibenzothiazolylhypericin
was synthesized and compared with the recently prepared 10,11-analogue. A significant difference in the ability to generate
singlet oxygen and/or reactive oxygen species and different absorption spectra of these two derivatives were observed. 相似文献