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991.
992.
Prokof'ev A. I. Solodovnikov S. P. Rasuleva D. Kh. Volod'kin A. A. Ershov V. V. 《Russian Chemical Bulletin》1970,19(7):1566-1568
Conclusions The polarographic reduction of certain methylenequinones was studied, and the mechanism of the reduction was investigated by the method of EPR spectroscopy.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1656–1658, July, 1970. 相似文献
993.
994.
995.
Russian Chemical Bulletin - 相似文献
996.
Trofimov B. A. Malysheva S. F. Gusarova N. K. Tatarinova A. A. Henkelmann J. 《Russian Journal of Organic Chemistry》2003,39(9):1356-1357
Russian Journal of Organic Chemistry - 相似文献
997.
S. V. Bushin A. K. Khripunov M. A. Bezrukova E. P. Astapenko 《Polymer Science Series A》2007,49(1):71-76
Cellulose myristate samples with a degree of substitution of 230–250 have been studied by the methods of molecular hydrodynamics (viscometry, analytical ultracentrifugation (flotation), and isothermal translational diffusion) in chloroform in the range M = (56–652) × 103. The experimental evidence has been interpreted within the framework of the generalized wormlike Yamakawa-Fuji model with the following parameters: the persistence length a = 115 × 10?8 cm, the chain diameter d = 45 × 10?8 cm, and the molecular mass per unit chain length M L = 270 × 108 cm?1. It has been inferred that the polymer dissolves in chloroform in the form of dimers. 相似文献
998.
The main feature of fluorite structure type is four families of crystallographic planes with dense trigon cation nets which
are mutually oriented as the faces of a regular octahedron. A complicated cation composition may cause lowering of general
symmetry to tetragonal (only one four-fold axis remains in the octahedral complex), rhombohedral (one three-fold axis), orthorhombic,
and monoclinic. The geometric parameters of the cation sublattice remain constant. They are close to the parameters of the
ideal face-centered cubic cation sublattice of fluorite (the measure of similarity is 1.00–0.81). This is true for all analyzed
fluoride structures and some U4+, Th4+, Zr, and Ln oxyfluorides. Thus, the concept is confirmed that the crystalline state is determined by systems of parallel
planes filled by dense heavy-atom nets.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Institute of Crystallography, Russian Academy
of Sciences. Translated fromZhurnal Struktumoi Khimii, Vol. 35, No. 1, pp. 71–80, January–February, 1994.
Translated by T. Yudanova 相似文献
999.
V. I. Kosyakov V. A. Shestakov S. F. Solodovnikov 《Journal of Structural Chemistry》1994,34(5):810-813
Using the Zimmennan-Pimentel potential, we have calculated the basic atomic coordinates of the unit cell of the gas hydrate HS-lframework. A minimum change in the strain energy of hydrogen bonh UH fakes place in formation of this framework from ice Ih. The dependence of UH on the lattice parameters is derived.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 5, pp. 175–178, September–October, 1993.Translated by T. Yudanova 相似文献
1000.