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1.
The interaction of comenic acid with cetylpyridinium chloride in aqueous solutions was studied by spectrophotometry. Compositions of ionic associates formed depending on cetylpyridinum chloride concentration were found, and logarithms of equilibrium constants of corresponding association reactions were determined. 相似文献
2.
T. V. Esipova A. A. Borisenko P. B. Terent’ev G. V. Grishina R. Herzshuh 《Russian Journal of Organic Chemistry》2006,42(5):742-747
A new class of endocyclic enamines, 1,6-disubstituted 1,2,3,4,5,6,7,8-octahydro-1,6-naphthiridines, was synthesized from 4-piperidone imines by successive subjecting the latter to lithiation with lithium diethylamide, to alkylation with 1-bromo-3-chloropropane, and to intramolecular cyclization. All stages were carried out as a unique process without isolation of the intermediate compounds. A thorough optimization of the process conditions, workup, and product storage was carried out. The conformational study of 1,6-disubstituted 1,2,3,4,5,6,7,8-octahydro-1,6-naphthiridines was performed. 相似文献
3.
E. L. Gaidarova K. Rosher A. É. Aliev G. V. Grishina 《Chemistry of Heterocyclic Compounds》1992,28(10):1175-1178
Enantiomericalfy pure (–)-(10S)-6,10-dimethyl-6-am-1,9-octahydroquinoline, which has been obtained from optically pure (3S)-1,3-dimethyl-3-(2-cyanoethyl)piperid-4-one, is a chiral intermediate for the preparation of novel biologically active compounds and an analog of piperidine and decahydroquinoline alkaloids. The chiroptical properties of the synthesized 6-azaoctahydroquinoline are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1379–1383, October, 1992. 相似文献
4.
G. V. Kotelnikov Sophia P. Moiseyeva E. V. Mezhburd E. I. Maevsky Elena V. Grishina 《Journal of Thermal Analysis and Calorimetry》2005,81(2):255-259
Summary Measurements of energy transformation in mitochondria are done on a capillary differential titration calorimeter CTD2156. It is important to mention that a sediment is quickly formed by the mitochondria suspension without mixing by means of a vibrating needle. During the measurements, the vibrating needle is located inside the working volume of the chamber. The design of the calorimeter is substantiated theoretically. It provides a new mode of a reagent input in the measuring volume of the calorimetric chambers. It expands the spectrum of tasks that can be solved using this instrument. In the capillary calorimeter the calorimetric chambers unit is simple and small in size. These advantages of capillary chambers provide an opportunity to unite 20 capillary calorimetric chambers in one calorimetric block. It allows designing a multi-channel titration calorimeter. There are obvious advantages of such a calorimeter over other instruments in screening researches and in researches of objects maintaining stability only for a short time. 相似文献
5.
P. A. Slepukhin E. S. Salmina V. A. Potemkin M. A. Grishina 《Journal of Structural Chemistry》2013,54(6):1091-1100
X-ray crystallography is used to investigate heteromolecular crystals of 3,6-bis(3,5-dimethylpyrazole-1-yl)-1,2,4,5-tetrazine with NH-donating azole derivatives. The effect is studied of the structure of azole on molecular packing in the crystal and the characteristics of covalent bonds in the molecule of 3,6-disubstituted tetrazine. The distribution of electron density critical points inside crystal cells is analyzed to identify and quantitatively describe the intermolecular interactions underlying the formation of lateral and stacking motifs. 相似文献
6.
G. V. Grishina 《Mathematical Notes》1997,62(5):586-595
We study equations of the form $$\begin{gathered} u_{tt} + Lu + b(x,t)u_t = a(x,t)\left| u \right|^{\sigma - 1} u, \hfill \\ - u_t + Lu = a(x,t)\left| u \right|^{\sigma - 1} u \hfill \\ \end{gathered}$$ , whereL is a uniformly elliptic operator and 0<σ<1. In the half-cylinder II0,∞={(x, t):x= (x 1,...,x n )∈ ω,t>0}, where ? ? ? n is a bounded domain, we consider solutions satisfying the homogeneous Neumann condition forx∈?ω andt>0. We find conditions under which these solutions have compact support and prove statements of the following type: ifu(x, t)=o(t γ) ast→∞, then there exists aT such thatu(x, t)≡0 fort>T. In this case γ depends on the coefficients of the equation and on the exponent σ. 相似文献
7.
Artemov A. N. Sazonova E. V. Aksenova N. A. Fukin G. K. Cherkasov A. V. Faerman V. I. Grishina N. Yu. 《Russian Chemical Bulletin》2019,68(8):1548-1554
Russian Chemical Bulletin - New heterocyclic compounds with phenyl chromium tricarbonyl substituents were synthesized by the reaction of triammine(tricarbonyl)chromium with phenyl-substituted... 相似文献
8.
A triangular lattice model for pattern formation by core-shell particles at fluid interfaces is introduced and studied for the particle to core diameter ratio equal to 3. Repulsion for overlapping shells and attraction at larger distances due to capillary forces are assumed. Ground states and thermodynamic properties are determined analytically and by Monte Carlo simulations for soft outer- and stiffer inner shells, with different decay rates of the interparticle repulsion. We find that thermodynamic properties are qualitatively the same for slow and for fast decay of the repulsive potential, but the ordered phases are stable for temperature ranges, depending strongly on the shape of the repulsive potential. More importantly, there are two types of patterns formed for fixed chemical potential—one for a slow and another one for a fast decay of the repulsion at small distances. In the first case, two different patterns—for example clusters or stripes—occur with the same probability for some range of the chemical potential. For a fixed concentration, an interface is formed between two ordered phases with the closest concentration, and the surface tension takes the same value for all stable interfaces. In the case of degeneracy, a stable interface cannot be formed for one out of four combinations of the coexisting phases, because of a larger surface tension. Our results show that by tuning the architecture of a thick polymeric shell, many different patterns can be obtained for a sufficiently low temperature. 相似文献
9.
G. V. Grishina E. L. Gaidarova E. R. Luk'yanenko A. A. Borisenko 《Chemistry of Heterocyclic Compounds》1996,32(2):194-196
The stereochemistry of the asymmetric reduction of the imine obtained from 1,3-dimethylpiperidin-4-one and (S)--phenylethylamine has been studied. It is shown that hydride reduction of imine 1 by sodium borohydride in methanol is asymmetric and gives the cis and trans diastereomeric pair 1,3-dimethyl-4-(-phenyl-ethylamino) piperidine in the ratio 3:1. Using sodium in isopropanol gives only one trans diastereomeric pair.1H NMR has been used to identify the stereochemical structure and diastereomer excess of the cis and trans isomers of 1,3-dimethyl-4-(-phenylethylamino)piperidine which had been separated by column chromatography.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 219–221, February, 1996. 相似文献
10.
A. V. Vannikov A. D. Grishina Yu. G. Gorbunova T. V. Krivenko A. S. Laryushkin L. A. Lapkina V. V. Savelyev A. Yu. Tsivadze 《Polymer Science Series A》2011,53(11):1069-1075
Poly(N-vinylcarbazole) layers containing tetra-5-crown-5-gallium phthalocyaninate (R4Pc)Ga(OH) are shown to possess photoelectric and photorefractive sensitivity at a wavelength of 1064 nm. This effect is associated with the formation of supramolecular ensembles of (R4Pc)Ga(OH) molecules with electronic optical absorption in the near-IR range and nonlinear optical properties. For the composite containing 5 wt % (R4Pc)Ga(OH) supramolecular ensembles, the dependence of the quantum efficiency of mobile-charge photogeneration on electric field E 0 is well fit by the Onsager equation expanded to E 0 3 at a quantum yield of electron-hole pairs of φ0 = 0.9 s with an initial separation radius of r 0 = 9.8 Å susceptibility χ(3) equal to 1.85 × 10?10 esu is measured via the well-known method of electric-field-induced second-harmonic generation. Two-beam-coupling gain coefficient Γ is found to be 80 cm?1 at E 0 = 120 V/μm. 相似文献