Causes of deformation of buildings on permafrost in railroad district of vorkuta

Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 15–17, May–June, 1989.     

Hydrolysis of Np(IV)

Hydrolysis of Np(IV) at p[H⁺] from 0 to 2.7 and ionic strength I = 0.1-1.0 was studied spectrophotometrically. In the p[H⁺] range from 0 to 2.2 and Np(IV) concentrations of 4.5 ×10^{- 5}-1.75 ×10^{- 4} M, polymerization and formation of colloids are negligible and do not noticeably affect the hydrolysis constant measurements. The hydrolysis is completely reversible. With increasing p[H⁺] to 2, only the NpOH^{3 +} complex is formed; the spectrum of this hydroxy complex was calculated. The typical narrow band of Np(IV) aqua ion occurs at 732.2 nm; in hydroxy complex, it is shifted to 729.5 nm and its intensity decreases by a factor of about 2.7. The average constant of Np(IV) hydrolysis equilibrium [Np^{4 +} + H₂O NpOH^{3 +} + H⁺] recalculated to the ionic strength I = 0 was determined as logK ₁ ⁰ = -1.23±0.06, which corresponds to the stability constant of the complex NpOH^{3 +} log₁ ⁰ = 12.77±0.06. The stability constant of the complex Np(OH)₂ ^{2 +} was calculated to be log₂ ⁰ = 24.3.     

Physico-chemical synthesis of diamond in metastable range

The present paper discusses the synthesis of diamond in its metastable region from carbonaceous gases, in particular methane. The diamond synthesis on seed crystals is made possible owing to the orientation effect of surface forces on the formation of a new phase. Discussed is also the joint crystallization of diamond and graphite. The basic experiments were made on highly dispersed diamond powders. The growth of diamond in kinetic and diffusion regions has been studied. Presented are results of studying the fractionation of stable carbon isotopes when growing a diamond.     

Application of the hydrodynamic analogy to the flow in a supersonic nozzle

We examine the flow of a supersonic stream in an annular duct. In approximation of the hydrodynamic analogy we have given consideration to both friction and heat transfer. A general equation is presented, as are the solutions for several special cases.