Showing papers by "Russian Academy of Sciences published in 1972"
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01 Jan 1972TL;DR: In this article, the authors introduce the notion of a stochastic differential equation and prove general theorems concerning the existence and uniqueness of solutions of these equations, which is a generalization of the notions of integral integral integral functions.
Abstract: In the present section we introduce the notion of a stochastic differential equation and prove some general theorems concerning the existence and uniqueness of solutions of these equations. For this purpose it is necessary to generalize the notion of a stochastic integral introduced above. Generally speaking, our approach to stochastic differential equations is based on the following considerations.
1,331 citations
547 citations
TL;DR: In this paper, the Weinberg model is applied to a large system of thermodynamically equilibrium weakly interacting particles and it is shown that at a temperature higher than about 10 3 GeV the symmetry broken at lower temperature is re-established, the masses of the intermediate bosons vanish and weak interaction becomes a long-range one.
542 citations
TL;DR: The hypothesis is advanced that after-hyperpolarization is the mechanism of diminution of inter-spike interval variability, the duration of after- HyperPolarization being correlated with the lower limit of motoneurone working frequency.
431 citations
380 citations
TL;DR: Families of static characteristics of both extensors and flexor were preserved during selective paralysis of gamma efferents by application of novocain to the muscle nerve.
354 citations
TL;DR: In this article, the Nusselt number was used for the analysis of turbulent heat and mass transfer in pipes, channels, and boundary layers, where the dimensionless coefficients of the universal logarithmic equations for the velocity and temperature profiles were derived.
279 citations
224 citations
TL;DR: Experimental results are given for the photoionization of rubidium vapor using a ruby-laser-pumped dye laser and a doubled ruby laser radiation, and photodissociation of HCl using the Raman-shifted output and the fourth harmonic output of a tunable Nd-glass laser.
Abstract: The general considerations for two-step photoionization of atoms and photodissociation of molecules using tunable laser sources are discussed. Experimental results are given for the (1) photoionization of rubidium vapor using a ruby-laser-pumped dye laser and a doubled ruby laser radiation, and (2) photodissociation of HCl using the Raman-shifted output and the fourth harmonic output of a tunable Nd-glass laser. The possibilities for other laser systems are also discussed.
182 citations
TL;DR: In this paper, the authors have measured the dynamic shear modulus and flow rate through capillaries under constant pressure and under constant velocity of the piston, for polybutadienes and polyisoprenes of narrow molecular weight distribution with molecular weights ranging, respectively, from 3.8 × 104 to 5.8× 105 and from 1.06 × 105 to 6.02 × 105.
Abstract: The dynamic shear modulus and the flow rate through capillaries under constant pressure and under constant velocity of the piston, have been measured for polybutadienes and polyisoprenes of narrow molecular weight distribution with molecular weights ranging, respectively, from 3.8 × 104 to 5.8 × 105 and from 1.06 × 105 to 6.02 × 105. The phenomena of the discontinuous increase of volume flow rate and self-oscillatory flow regime at critical rates of deformation have been considered in detail. It is proposed that these phenomena are due to the induced transition of the polymer from the fluid to the high-elastic state at higher deformation rates. As a result, an inference has been made that polybutadienes and polyisoprenes with a narrow molecular weight distribution in the high-elastic state, behave in certain respects as crosslinked polymers incapable of displaying fluidity. The quantitative relationships among the viscoelastic characteristics measured under dynamic regimes, the parameters determining the critical flow regimes, and the molecular weights of polybutadienes and polyisoprenes have been worked out.
173 citations
TL;DR: In this paper, it was found that with the laser excitation, narrow lines (≈1 cm-1) appeared instead of broad bands ( ≥200 cm- 1) in the fluorescence spectrum of both the crystalline and glass-like solid solutions.
01 Jan 1972
TL;DR: In this paper, a generalized thermal equation of adsorption, i.e., ψ(θ, p, T) = 0, applicable to the quantitative description of molecules sharply differing in electronic structure on microporous adsorbents widely different in nature (active carbons, zeolites, etc.) is considered.
Abstract: Adsorption on a nonporous, nonswelling adsorbent and adsorption in micropores represent two limiting cases of physical adsorption which are clearly distinguishable thermodynamically. In the first case, the chemical potential of the adsorbent is independent of the amount of the adsorbed substance; in the second case, it varies with it. The works of Brunauer, which made a whole epoch in the theory of adsorption, belong to the first type of adsorption phenomena; adsorption in micropores, however, is beyond the framework of his investigations. It should be treated in terms of volume filling, and not of layer-by-layer coverage of the surface. In computational methods of the theory in hand, a substantial role is played by the concept of the temperature invariance of free energy of adsorption as a function of the degree of filling. An analysis of this concept is given and the limits of its applicability are assessed. Exact and approximate expressions for the calculation of the basic thermodynamic functions in adsorption in micropores have been obtained. A generalized thermal equation of adsorption, i.e., ψ(θ, p, T) = 0, applicable to the quantitative description of adsorption of molecules sharply differing in electronic structure on microporous adsorbents widely different in nature (active carbons, zeolites, etc.) is considered.
TL;DR: In this article, the specific features of the dislocation structure, occuring in the vicinity of indentations have been studied using Si single crystals under different conditions of deformation (at temperatures of 20 to 700 °C and loadings of 0.5 to 10 p).
Abstract: The specific features of the dislocation structure, occuring in the vicinity of indentations have been studied using Si single crystals under different conditions of deformation (at temperatures of 20 to 700 °C and loadings of 0.5 to 10 p). It is shown, that the deformation of crystals at temperatures of 350 to 650 °C results in twin formation with {111} twinning plane. Flat defects with {115} habit plane are revealed. They are shown to be platelets of a new phase, which is of the hexagonal structure with c = 6.31 A and a = 3.86 A. The possible mechanism of the phase transformation is discussed.
[Russian text ignored].
TL;DR: In this article, a theoretical treatment of the fluctuation mechanism involved in the generation of picosecond laser pulses with saturable absorbers is presented, where the processes responsible for shortening of the pulsewidth and for selection of the most intense pulse are treated.
Abstract: This paper presents a theoretical treatment of the fluctuation mechanism involved in the generation of picosecond laser pulses with saturable absorbers. The processes responsible for the shortening of the pulsewidth and for selection of the most intense pulse are treated. Some experimental results that confirmed the treatment are presented. The influence of inertia of saturable absorber and nonlinear losses (self-focusing and self-modulation) is discussed.
TL;DR: By ESR technique, the formation of adsorbed O2− and O− on TiSiO2, VSiO2 and Vγ-Al2O3 has been studied as mentioned in this paper.
TL;DR: In this article, the reliability of prediction, made on the basis of noted anomalies of some parameters, is estimated, and an example of prediction of place, energy and time of the earthquake as well as the estimation of the error of prediction is given using anomalies of the ratios of longitudinal and shear wave velocities.
TL;DR: In the present study an attempt has been made to obtain compact double-stranded molecules of DNA in solution and to determine some physico-chemical properties of the ensuing structural form of DNA.
TL;DR: In this paper, the authors investigated submicrocracks, free radicals, and endgroups of scissioned molecules formed in polyethylene, polypropylene, and polycaprolactam under uniaxial tension.
Abstract: Submicrocracks, free radicals, and endgroups of scissioned molecules formed in polyethylene, polypropylene, and polycaprolactam under uniaxial tension have been investigated. Measurements were carried out by small-angle x-ray scattering, electron paramagnetic resonance, and infrared spectroscopy. The concentration of submicrocracks is almost the same as that of free radicals but is smaller than the concentration of scissioned macromolecules by approximately three orders of magnitude. The number of scissions per crack proved to be close to the number of macromolecules passing through the cross section of a submicrocrack calculated on the assumption of close packing. It is concluded that submicrocracks in stressed polymers are formed as a result of chain reactions of macromolecular decomposition initiated by the active end primary free radicals.
TL;DR: In this paper, a light-water neutron trap in the reactor active zone as a γ-ray source was used to measure the circular polarization of the reaction n+p → d+ γ.
TL;DR: In this paper, carbon black filled polyisobutylene samples (of low and high molecular weight) have shed light on the relationship between the behavior of disperse and polymeric systems.
Abstract: Rheological properties of carbon black filled polyisobutylene samples (of low and high molecular weight) have shed light on the relationship between the behaviour of disperse and polymeric systems. At sufficiently high filler concentration a structural skeleton seems to appear. This affects the properties.
TL;DR: The age of diatom oozes from the South West Africa shelf is (24(±27)·10 3 years for the South-West African nodules and 55(±35)· 10 3 months for the Chilean nodules as mentioned in this paper.
TL;DR: A strong influence of ns2np6 → ns 2np5 ϵd transition on the outer ns subshell photoionization cross section of noble gas atoms is demonstrated in this paper.
TL;DR: In this paper, a priori assumptions about the degree of smoothness of the probability density to be estimated were made and they were used to construct estimates of a probability density function itself and its derivatives which are distinguished by the high rate of decrease of the error in the estimate as the sample size increases.
Abstract: We investigate statistical estimates of a probability density distribution function and its derivatives. As the starting point of the investigation we take a priori assumptions about the degree of smoothness of the probability density to be estimated. By using these assumptions we can construct estimates of the probability density function itself and its derivatives which are distinguished by the high rate of decrease of the error in the estimate as the sample size increases.
TL;DR: In this paper, a theory has been developed for outer-sphere non-adiabatic electron transfer reactions at electrodes, to or from which an electron is transferred via ionic or molecular bridge species adsorbed on the electrode surface.
TL;DR: Thirty-seven species of marine invertebrates from different systematic and ecological position were quantitatively tested for cellulase and chininase activity in their digestive systems, and Ascidia Halocyntia aurantium and Metridium senile fimbriatum were found to possess the highest chitin enzyme activity.
Abstract: 1. 1. Thirty-seven species of marine invertebrates from different systematic and ecological position were quantitatively tested for cellulase and chininase activity in their digestive systems. 2. 2. Enzymes were tested by several methods. Carboxymethlcellulase (CMC-ase) and carboxymethylchitinase (CMCh-ase) activities were estimated by the decrease in viscosity of these solutions and by the increase of the reducing sugars. Chitinase activity by precipitated chitin (PCh) was tested by the simultaneous measurement of the reducing sugar (RS) and N-acetylglucosamine (NAGA) in an incubation mixture and by chitin (Ch), using the last method only. 3. 3. Ascidia Halocyntia aurantium and Metridium senile fimbriatum were found to possess the highest chitinase activity; mollusca Littorina mandschurica and L. brevicula had the highest cellulase activity.
TL;DR: DNA-like RNA (dRNA) is found in the nucleus as a complex with globular protein particles called informofers, and can form complexes in vitro and in vivo with different kinds of dRNA, including virus-specific RNA synthesized in adenovirus-infected cells.
Abstract: DNA-like RNA (dRNA) is found in the nucleus as a complex with globular protein particles called informofers. Intact informofers may be detached from the dRNA and can form complexes in vitro and in vivo with different kinds of dRNA, including virus-specific RNA synthesized in adenovirus-infected cells.
TL;DR: It is suggested that the thermodynamic incompatibility of gelatin with D D-glucans in isoionic conditions is determined by self-association of gelatin macro-ions due to interaction of charge fluctuations.
TL;DR: The end-analysis of nuclear dRNA fractions, combined with competitive hybridization, was developed to check the predictions following from the model of the structure of the transcriptional unit in Eukaryotes and shows that the ends of operons encode a true mRNA, transferred into polysomes.
01 Jan 1972