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61.
A. P. Avdeenko S. A. Zhukova S. A. Konovalova 《Russian Journal of Organic Chemistry》2001,37(3):382-387
The chlorination and bromination of 2,3-dimethyl-, 3-methyl-6-isopropyl-, and 2,6-diisopropyl-4-aroyl(or arylsulfonyl)oxyimino-2,5-cyclohexadienones follow the proposed rules of halogenation of 4-aroyl(or arylsulfonyl)oxyimino-2,5-cyclohexadienones: the reaction occurs preferentially at the cis-CÍC bond of the quinoid ring; simultaneous halogenation at both double bonds is not observed; halogen adds mainly across unsubstituted CÍC bond; no halogenation occurs at the double bond already substituted by a halogen; bromination of the CÍC bond with an alkyl substituent is more difficult than chlorination; the second halogen molecule adds only after regioselective dehydrohalogenation. 相似文献
62.
E. P. Baberkina V. N. Buyanov M. E. Zhukova A. E. Shchekotikhin V. E. Zhigachev N. N. Suvorov 《Chemistry of Heterocyclic Compounds》2001,37(10):1234-1237
The corresponding Mannich bases have been synthesized by the aminomethylation of 6-methyl-1H-pyrrolo[2,3-a]- and 4-methyl-3H-pyrrolo[3,2-c]phenanthridinium iodides. The interaction of 6-chloro-phenanthridine with indoline and with 5-amino-N-acetylindoline gave the corresponding derivatives of phenanthridine. 6-(1-Indolyl)phenanthridine has been obtained by the dehydrogenation of 6-(1-indolinyl)phenanthridine with manganese dioxide. 相似文献
63.
International Applied Mechanics - A procedure for analytical solution of the problem of the stability and post-buckling behavior of composite cylindrical shells with local deflection under axial... 相似文献
64.
The automorphism group of a G-structure of finite type and order k on a smooth n-dimensional orbifold is proved to be a Lie group of dimension n+dim(g+g
1+...+g
k-1), where g
i
is the ith prolongation of the Lie algebra g of a given group G. This generalizes the corresponding result by Ehresmann for finite type G-structures on manifolds. The presence of orbifold points is shown to sharply decrease the dimension of the automorphism group of proper orbifolds. Estimates are established for the dimension of the isometry group and the dimension of the group of conformal transformations of Riemannian orbifolds, depending on the types of orbifold points. 相似文献
65.
Yu. I. Tarasevich S. V. Bondarenko V. V. Brutko A. I. Zhukova G. N. Malysh I. G. Polyakova 《Russian Journal of Applied Chemistry》2003,76(10):1577-1582
Structural and sorption characteristics of natural carbonaceous sorbents and thermally expanded graphite were examined. Acid-base sites on the sorbent surface were characterized qualitatively and quantitatively. The performance of the materials in wastewater treatment to remove anionic surfactants was studied. 相似文献
66.
Institute of Mechanics, Ukrainian Academy of Sciences, Kiev. Translated from Prikladnaya Mekhanika, Vol. 28, No. 10, pp. 41–46, October, 1992. 相似文献
67.
Conclusions If the defining equation corresponding to the number k0<0 has a multiple root
0(t)
, then Theorem I is inapplicable. In this case to find particular solutions of (I) one should, with the help of the substitution (t)=k
00(t)+(t) pass to an equation for (t) and investigate it by the method of Newton's diagram.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 37, No. 6, pp. 695–702, November–December, 1985. 相似文献
68.
A. V. Bludenko T. P. Zhestkova T. N. Zhukova A. V. Ponomarev 《High Energy Chemistry》2006,40(6):370-374
The transformations of kinetically stable aqueous humic acid solutions saturated with Ar, N2O, or air by the action of fast electrons at absorbed doses to 20 kGy were studied. In radiolytic and postradiation processes, humic acid was converted into insoluble compounds, whose precipitation accelerated with dose. The formation of insoluble compounds was enhanced in neutral and acidified solutions saturated with air and/or N2O. As low-molecular-mass carboxylic acids that resulted from the radiolytic fragmentation of humic acid were accumulated in solution, the phase transformation weakened. The irradiated solutions were easy to purify by chemical coagulation. 相似文献
69.
S. A. Yamaskhin G. A. Romanova E. A. Oreshkina N. V. Zhukova 《Chemistry of Heterocyclic Compounds》2006,42(1):77-85
It has been shown that the condensation reaction of 5-amino-2,3-dimethyl-and 1,2,3-trimethylindoles with 4,4,4-trifluoroacetoacetic
ester occurs either via the trifluoromethylcarbonyl or the ester group depending upon the conditions under which it is carried
out. Under thermal conditions (refluxing in diphenyl) the enaminocrotonates formed are readily converted to pyrrolo[3,2-f]quinolines
and the amides cyclize in trifluoroacetic acid at 78°C to give pyrrolo[2,3-g]quinolines.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 86–96, January, 2006. 相似文献
70.
Piryatinskii Yu. P. Nazarenko V. G. Vasyuta R. M. Kachkovskii A. D. Maiboroda E. I. Zhukova O. A. Slominskii Yu. L. Tolmachev A. I. 《Theoretical and Experimental Chemistry》2003,39(4):230-234
Measurements were carried out for time-resolved fluorescence spectra of dye solutions containing thiacarbocyanine and its derivatives with ethylene and vinylene bridges in the polymethine chain. At low temperature, an additional band appears in the spectrum related to an intramolecular electronic transition. Analysis of the transition lifetimes and a quantum-chemical model indicated that this transition should be attributed to a short-lived asymmetrical component formed along with the symmetrical component upon relaxation of the excited state but not appearing at room temperature due to conformational transformations. 相似文献