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1.
A. F. Blinokhvatov O. V. Markovtseva M. N. Nikolaeva 《Chemistry of Heterocyclic Compounds》1992,28(3):266-268
Substituted 4H-pyrans were obtained in high preparative yields by the reaction of 1,5-diketones with acetic anhydride and boron trifluoride etherate in diethyl ether. It is assumed that the heterocyclization of 1,5-diketones includes a step involving the formation and transformations of an acyloxy carbonium ion.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 320–322, March, 1992. 相似文献
2.
O. A. Nikolaeva V. I. Kodolov L. G. Makarova A. Yu. Volkov E. G. Volkova 《Physics of the Solid State》2002,44(3):525-526
Metal-containing carbon nanostructures are prepared by heating poly(vinyl alcohol) in mineral media with a lamellar structure at a temperature below 300°C. It is demonstrated that three possible types of nanostructures can be formed, namely, multilayer carbon nanotubes, spherical carbon nanoparticles, and finely crystalline carbon structures. According to the data of transmission electron microscopy, the nanotube size falls in the range from 50 to 300 nm and the nanotubes themselves have a stranded structure. 相似文献
3.
本文对广义风险过程中的渐近方差作了非参数估计,得出并证明了两个定理,为广义风险过程中破产概率的区间估计作了理论准备. 相似文献
4.
5.
Khrapkovskii G. M. Nikolaeva E. V. Chachkov D. V. Shamov A. G. 《Russian Journal of General Chemistry》2004,74(6):908-920
Semiempirical, ab initio, and density functional theory calculations were used to study the primary act of gas-phase monomolecular decomposition of certain C-nitro compounds and their radical cations, associated with the nitro-nitrile rearrangement. It was shown that the reaction fails to occur with all neutral molecules of aliphatic nitro compounds (except for fluoronitromethane and fluoronitroethene) and has a much lower barrier with the corresponding radical cations. An important role of the nitro-nitrile rearrangement in gas-phase decomposition of aromatic nitro compounds was demonstrated. 相似文献
6.
7.
8,8"-Biflavonoidsareantw0rtantclass0fbiflavonoids.Asasystematicresearchofthe8,8"-biflav0noids,wehavepreviouslyreportedthestudyonthereactionof2'-hydroxychaloneswithl2-H2SO4-DMSOsystem.'InthispaPer,thesynthesisof5,5",7,7',-tetTameth0xy-8,8"-biflavonela2,4,4",7,7"-tetramethoxy-8,8"-biflavone1b',4',4",,5,5,',7,7"-hexamethoxy-8,8"-biflav0ne1c4and4,4"-dibenZyl0xy-5,5",7,7"-tetramothoxy-8,8"-biflavoneldisreported.ThesyntheticmethodisshownintheSchemebelow.2-Hydroxyacet0phenonescondensedwithsubsti… 相似文献
8.
A. R. Burilov D. V. Cherepachkin I. L. Nikolaeva M. A. Pudovik 《Russian Chemical Bulletin》1995,44(2):345-349
Some newS-phosphorylated,S-silylated, andS-stannylated derivatives of -mercaptoketones were obtained. The reactions of some of these compounds induced by the temperature and by molecular oxygen as well as the phosphorylation of the Si- and Sn-containing derivatives were studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 353–357, February, 1995. 相似文献
9.
S. N. Nikolaeva A. S. Zolotareva S. V. Ponomarev V. S. Petrosyan 《Russian Chemical Bulletin》1994,43(5):857-861
Dialkylamino- and alkoxytrialkylstannanes have been studied as N- and O-nucleophilic reagents in substitution reactions at the B-Br bond. The previously unknown bis(dialkylamino)- and dialkoxyboryl trialkylsilyl ketenes were synthesized. Some peculiarities of the reactivity of these compounds have been studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 911–915, May, 1994.This research was carried out in the framework of the Universities of Russia State Program. 相似文献
10.
高效液相色谱氮杂冠醚键合固定相的合成及性能研究 总被引:2,自引:0,他引:2
我们曾用γ-氯丙基键合硅胶(CPS),在氢化钠(NaH)作用下合成了3-(氮杂-18-冠-6)丙基键合固定相(BCP)[1].该固定相对碱基、核苷酸、硝基苯酚等有较好的分离选择性,但由于NaH对硅胶基质腐蚀作用较大,导致BCP柱效及渗透性较低.本文采... 相似文献