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31.
V. V. Ivanov Yu. A. Kotov V. P. Gorelov V. N. Borisov A. M. Murzakaev O. M. Samatov A. I. Medvedev V. R. Khrustov S. Yu. Ivin S. V. Zayats V. B. Balakireva N. V. Sharova A. V. Kuz’min E. G. Vaganov N. I. Moskalenko 《Russian Journal of Electrochemistry》2005,41(6):612-619
The effect of the composition and density of ceramics on the electroconductivity of solid electrolytes Ce1 − x
GdxO2 − δ(x = 0.09–0.31) with a submicron (0.1–0.3 µm) grain size, which are prepared from nanosized powders, is investigated. The powders are synthesized by two methods, specifically, by evaporation of a target with the aid of the radiation of a pulsed carbon dioxide laser and by a chemical method of burning. The samples of ceramics are prepared by magnetopulsed or quasi-isostatic (200–500 MPa) pressing and subsequent caking in air at a temperature of 1100–1300°C. It is established that the electroconductivity of the obtained solid electrolytes is higher and the effective activation energy for conduction is considerably lower as compared with analogous electrolytes with a micron grain size.__________Translated from Elektrokhimiya, Vol. 41, No. 6, 2005, pp. 694–701.Original Russian Text Copyright © 2005 by Ivanov, Kotov, Gorelov, Borisov, Murzakaev, Samatov, Medvedev, Khrustov, Ivin, Zayats, Balakireva, Sharova, Kuz’min, Vaganov, Moskalenko.Published on the basis of a contribution delivered at the VII Meeting on Fundamental Problems in Solid-State Ionics (Chernogolovka-2004). 相似文献
32.
The reaction of 4-chloro-2-ethylthio-6-methylpyrimidine with 30% H2O2 in ethanol with heating forms 5-chloro-6-methyluracil instead of the expected 4-chloro-2-hydroxy-6-methylpyrimidine. Under similar conditions but in the presence of HC1, 6-methyluracil and 2-ethylthio-4-hydroxy-6-methylpyrimidine are also converted into 5-chloro-6-methyluracil.For part IV, see [10]. 相似文献
33.
Copolymers of ethyl acrylate (M1) and n-butyl methacrylate (M2) were prepared by benzoyl peroxide initiation in solution at 60° and copolymer compositions estimated by [13C]-NMR spectroscopy. The kinetic behaviour is approximately ideal with r1 = 1/r2 = 0.47. Relaxation times T1 were determined for six of the carbons in M2 units and one in the M1 units; they range from 0.07 to 1.65 sec. 相似文献
34.
G. A. Mironova E. N. Kirillova V. N. Kuklin N. A. Smorygo B. A. Ivin 《Chemistry of Heterocyclic Compounds》1984,20(10):1088-1094
The reaction of 2-aryl-4-hydroxy-6-oxo-1,3-thiazines with Vilsmeier's reagent results in the formation of a mixture of 2-aryl-6-oxo-4-chloro-1,3-thiazines and their 5-formyl analogs. Reactions involving the nucleophilic replacement of the halogen and nucleophilic addition to an aldehydic group have been studied. The intramolecular cyclization of the oxime and phenylhydrazone of 6-oxo-2-phenyl-5-formyl-4-chloro-1,3-thiazine gives new heteroaromatic systems, viz., isoxazolo-[4,5-d]-1,3-thiazine and pyrazolo]4,5-d]-1,3-thiazine, respectively.For report 54 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1328–1334, October, 1984. 相似文献
35.
V. S. Mirzoryan R. G. Melik-Ogandzhanyan T. N. Rusavskaya G. V. Rutkovskii B. A. Ivin 《Chemistry of Heterocyclic Compounds》1988,24(5):508-514
The mass spectra of 5-m- and p-substituted benzylidenehydantoins, their thio analogs and 5-carbethoxymethylenehydantoins with a substituent at the -carbon atom of the side chain were studied. The fragmentation of the molecular ions of 5-arylidenehydantoins proceeds in one direction, splitting of the X=C-NR-C=O fragment, irrespective of the substituent in the benzene ring. The peak intensity of the fragmentary ions formed from the molecular ions is linearly dependent on the -constants of the substituent. The direction of the fragmentation of 5-ethoxycarbonylmethylenehydantoins markedly depends on the substituent at the -carbon atom in the side chain that determines the stability of the hydantoin ring and the carboethoxyl group. The fragmentation of these compounds under electron impact proceeds by five paths, related to splitting of fragments O=C(2)NCH(4)=O, C2H4, C2H5O, C2H5OH, and COOC2H5.See [1] for Communication 64.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 625–631, May, 1988. 相似文献
36.
Synthesis of 2,5‐Disubstituted Derivatives of Pyrano[2,3‐d][1,3]thiazines via the Interaction of 2‐Substituted 4‐Hydroxy‐6H‐1,3‐thiazine‐6‐ones with Aldehydes 下载免费PDF全文
Roman V. Shutov Marina V. Sopova Alexander V. Krylov Andry N. Kaluzhskikh Boris А. Ivin 《Journal of heterocyclic chemistry》2015,52(6):1618-1624
A new and efficient route for the synthesis of derivatives of the poorly investigated pyrano[2,3‐d][1,3]thiazine heterocyclic system is disclosed. These compounds were prepared via annulation of 2‐aryl‐4‐hydroxy‐6H‐1,3‐thiazine‐6‐ones with aliphatic and aromatic aldehydes in the presence of pyridine. The method is general and versatile, and the interaction is independent on the nature of the aldehyde, the only exceptions being formaldehyde and salicylaldehydes. 相似文献
37.
K. J. Ivin M. Navrtil N. A. Walker 《Journal of polymer science. Part A, Polymer chemistry》1972,10(3):701-708
100-MHz NMR spectra are reported for solutions of the 1:1 copolymers of sulfur dioxide with hex-1-ene, cis- and trans-but-2-enes, cyclohexene, cyclopentene, and norbornene, including the deuterated polymers made from hex-1-ene-2-d1, cis- and trans-but-2-ene-2,3-d2, and cyclohexene-3,3,6,6-d4. The resolution of the spectrum of poly-(hex-1-ene sulfone) was very poor in CCl4 as solvent but good in polar solvents. The main-chain CH2 protons are nonequivalent, and their chemical shifts show sensitivity to dyad structure; the α-CH2 protons are also non-equivalent. The spectra of most of the other polymers are discussed in terms of possible preferential modes of addition as well as tacticity effects. 相似文献
38.
E. V. Fedorova V. V. Kvasha E. P. Studentsov A. V. Moskvin B. A. Ivin 《Russian Journal of General Chemistry》2007,77(4):589-595
Glycosylation of 5-phenylpyrano[2,3-d:6,5-d′]dipyrimidine-4,6-diones through the corresponding di-O-trimethylsilyl derivative with excess 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose gives a mixture of 3-mono-and 3,7-bis(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-5-phenylpyrano[2,3-d:6,5-d′]dipyrimidines; in the reaction with equimolar amounts of the reactants, only the monoriboside is formed. Isomeric N,N′-disubstituted
pyranodipyrimidines, as well as mixtures of their mono-and disubstituted derivatives can be separated by fractional crystallization.
The alkylation of pyrano[2,3-d:6,5-d′]dipyrimidine-4,6-dione and its 5-phenyl-substituted derivative with 2-oxabutane-1,4-diyl diacetate provides an efficient
procedure for the synthesis of acyclic analogs of glycosides based on pyrano[2,3-d:6,5-d′]dipyrimidines.
Original Russian Text ? E.V. Fedorova, V.V. Kvasha, E.P. Studentsov, A.V. Moskvin, B.A. Ivin, 2007, published in Zhurnal Obshchei
Khimii, 2007, Vol. 77, No. 4, pp. 630–636.
For communication CXXVI, see [1]. 相似文献
39.
In the reaction of malonyl dichloride with substituted -enzamides, cyclic and linear products and their mixtures form, depending on the solvent and the ratio and concentrations of reagents. When the reaction is carried out in dilute dichloroethane solution, pure 2-aryl-1,3-oxazin-4,6-diones without a substituent at C(5) are obtained in good yield. These materials are extremely unstable, and in the presence of traces of water are converted to the respective N-aroylmalonamic acids.For Communication 60, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 382–385, March, 1987. 相似文献
40.