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91.
Ol'shanskaya L. N. Popova S. S. Pominova T. V. Astaf'eva E. N. 《Russian Journal of Electrochemistry》2002,38(4):356-361
Kinetics of processes occurring during anodic dissolution of Li
x
C6 electrodes formed in structures of carbonized fiber and cloth (CC) in solutions of lithium perchlorate in a mixture of propylene carbonate and dimethoxyethane is studied. It is shown that the Li
x
C6 (CC) electrodes have an approximately three times greater intercalation capacity, which is caused by specific features of the structure of CC. Values of the initial concentration of lithium defects in the structure of a surface layer of the CC matrix and the diffusion coefficients for lithium in the temperature range 293–323 K are calculated. 相似文献
92.
Yu. V. Goryushkina A. S. Monaenkova A. A. Popova L. A. Tiflova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(5):697-701
The enthalpy of reaction between praseodymium metal and 1.07 n HCl and the enthalpy of solution of praseodymium trichloride in 1.07 n HCl and water were measured in a swinging isoperibol calorimeter at 298.15 K. The results were used to calculate the enthalpy of formation of the praseodymium ion in the state of an infinitely dilute aqueous solution, Δf H°298.15 Pr3+(sln, ∞H2O) = ?687.8 ± 1.7 kJ/mol. 相似文献
93.
E. N. Popova V. E. Yudin N. V. Kukarkina T. A. Kostereva I. V. Gofman V. V. Kudryavtsev 《Russian Journal of Applied Chemistry》2006,79(3):439-444
A series of foamed organoplastics based on a combination of foamed fully aromatic polyimide binders and Arimid T polyimide felt were prepared. New composite foamed organoplastics reinforced with montmorillonite nanoparticles were prepared using commercially available aromatic monomers. 相似文献
94.
95.
N. B. Mel’nikova E. N. Kochetkov S. E. Solov’eva E. V. Popova I. S. Antipin A. E. Bol’shakova O. E. Zhil’tsova A. I. Konovalov 《Russian Chemical Bulletin》2011,60(9):1948-1955
The possibility of designing a model of sensor to antioxidants based on thiacalix[4]arene monolayers with immobilized cytochrome c was shown. The molecular surface area S 0 of thiacalix[4]arene in the monolayers and the surface pressure coefficient ?dπ/dS (elasticity) reflect changes in the redox state of cytochrome c in the presence of dihydroquercetin and ascorbic acid in the aqueous subphase. The absorption spectra in the visible and UV ranges of solutions of the subphase and transferred thiacalix[4]arene monolayers with immobilized cytochrome c confirm the oxidation of the antioxidants to quinones and formation of the reduced form of cytochrome c. 相似文献
96.
V. E. Smirnova E. N. Popova V. M. Svetlichnyi L. A. Myagkova A. N. Orekhov V. E. Yudin A. M. Muzafarov E. A. Tatarinova 《Russian Journal of Applied Chemistry》2011,84(10):1800-1804
The effect exerted by thermal aging in air at 350°C on the thermal and mechanical properties of composite films prepared on the basis of heat-resistant polyimide PM and non-film-forming polymethylphenylsiloxane (PMPS) was examined. The phase segregation of polymeric composites of various compositions and the thermal aging rate were evaluated. 相似文献
97.
A. M. Bochek N. M. Zabivalova I. I. Gavrilova I. V. Gofman I. V. Abalov E. N. Popova V. E. Yudin V. K. Lavrent’ev E. F. Panarin 《Polymer Science Series A》2014,56(2):158-168
The rheological properties of dilute and moderately concentrated solutions of methyl cellulose blends with poly(N-methyl-N-vinylacetamide) in water and dimethylacetamide are studied, and the stressstrain characteristics of the composite films based on these blends are estimated. DSC, X-ray diffraction, and thermomechanical analysis are used to investigate the structural organization of composite films, to estimate the temperatures of relaxation transitions, and to determine the composition ranges in which the polymers are compatible and form mixed structures. 相似文献
98.
D. A. Kazakov V. V. Vol’khin I. S. Borovkova N. P. Popova 《Russian Journal of Applied Chemistry》2014,87(1):88-94
Effect of the ion composition of aqueous solutions on the oxygen absorption kinetics in a system constituted by a gas (air) and a liquid (aqueous solution) in the presence of microencapsulated quartz particles activating the mass transfer in the liquid phase was studied. It was found that ions with positive hydration cause a substantial decrease in the O2 mass-transfer enhancement factor, whereas ions with negative hydration lead to its increase under the same conditions. It is shown that the effect of ions on the rate of oxygen absorption by aqueous electrolyte solutions can be prognosticated on the basis of data on the influence of these ions on the structure and viscosity of water. The results of the study can serve as a basis for varying the rate of heterogeneous reactions in gas-liquid systems, whose rate is limited by the mass transfer of oxygen into aqueous media, by purposeful control over their ion composition. 相似文献
99.
100.
John D. Spence Miranda L. Lackie Nicola A. Clayton Sergio A. Toscano Michelle A. Farmer Esfir Popova Marilyn M. Olmstead 《Tetrahedron letters》2014
Sonogashira coupling of buta-1,3-diynylbenzene with ((2-iodophenyl)ethynyl)trimethylsilane and 1,2-diiodobenzene led to the novel enetriyne, 1-ethynyl-2-(phenylbuta-1,3-diynyl)benzene, and enetetrayne, 1,2-bis(phenylbuta-1,3-diynyl)benzene, respectively. Solid state structural and thermal analyses are also described. In solution, 1-ethynyl-2-(phenylbuta-1,3-diynyl)benzene was found to undergo thermal Bergman cyclization to afford 2-(phenylethynyl)naphthalene. 相似文献