# Доклады Национальной академии наук Беларуси, 2000, Том 44, No.2

/ Издания академии / Научные журналы

Доклады Национальной академии наук Беларуси, 2000, Том 44, No.2

## СОДЕРЖАНИЕ

**МАТЕМАТИКА**

*Korzyuk V.I., Lemeshevsky S.V., Matus P.P.*
**Conjugation problem of joint-separate flow of viscoelastic and viscous fluids in plane duct.** pp. 5--8

*Summary:* The problem of conjugation concering joint separate flow of viscoelastic and viscous fluids in a plane duct is considered. By method of energy inequalities and averaging operators with variable step existence of a unique strong solution of this problem is proved in the general multidimensional case. For numerical solution of one-dimensional conjugation problem difference scheme is constructed. The consistency conditions on the interface are approximated with the second order of accuracy with respect to spatial variable. Error estimate for the difference scheme is obtained.

*Gabasov R.F., Kirillova F.M., Ruzhitskaya E.A.*

**Stabilization of inverted pendulum.** pp. 9--12

*Summary:* A stabilization method for nonlinear model of inverted pendulum under large perturbation of initial state is described. Results are illustrated by numerical calculations.

*Makarov E.K., Rachkovsky N.N., Son Wen*

**Arcwise connectedness of closed maximal point set for convex compactum.** pp. 13--15

*Summary:* We prove that the efficient point set of a compact convex set in a Hausdorff topological vector space is arcwise connected provided it is closed.

*Starovoitov A.P.*

**The problem of describing sequencies of best trigonometric rational approximations.** pp. 16--18

*Summary:* For any nonincreasing sequence {*a*_{n}}_{n}^{¥}, *a*_{n} ® 0, *a*_{n} ³ 0 of real numbers the continuous 2p-periodic function *f*, with
the properties *R*_{n}^{T} (*f*) = *a*_{n}, *n* = 0, 1, 2,..., has been constructed, where *R*_{n}^{T} (*f*) are the best uniform rational approximations of the 2p-periodic function *f* by trigonometric rational functions of degree not exceeding *n*.

*Kruger A.Ya.*

**Strict (e, d)-semidifferentials and extremality of sets and functions.** pp. 19--22

*Summary:* New definitions of extremality for sets and functions are offered. Necessary and sufficient extremality conditions are stated in Asplund spaces in terms of strict d-semidifferentials and strict d-normals.

*Yablonsky O.L.*

**Classification of approximation methods for stochastic integrals in algebra of generalized stochastic processes.** pp. 23--25

*Summary:* Approximation methods for stochastic integrals in the algebra of generalized stochastic processes and their classification are considered.

*Kukrak G.O.*

**Hyperspace and perfect maps.** pp. 26--27

*Summary:* This paper deals with properties of maps induced by closed maps of topological spaces on their hyperspaces. Some applications of the results to the theory of absolutes are discussed.

*Kovalevskaya E.I.*

*p*-Adic version of Khintchine's theorem for planar curves in convergence case. pp. 28--30

*Summary:* We prove a *p*-adic analogue of the convergence part of Khintehine's theorem for planar curves with non-zero curvature.

*Lepin V.V.*

**Space complexity of accessibility problem for frontwidth-constrained graphs.** pp. 31--33

*Summary:* We show that the graph accessibility problem for graphs of frontwidth *h*(*n*) can be solved in space *O*(*h*(*n*)(log *n*).

**ИНФОРМАТИКА**

*Listopad N.I.*
**Synthesis of optimal networks.** pp. 34--37

*Summary:* Six models of optimum network synthesis for telecommunication are considered. The approach is based on the methods of discrete optimization. Some demands are formulated for emergency situations when the telecommunication network is breakdown. The results are confirmed by the UNIBEL network operating.

**ФИЗИКА**

*Knyazev M.A.*
**Formation of coupled states in scalar theory F**^{4}. pp. 38--41

*Summary:* Conditions favouring of coupled states of soliton-like objects in scalar F^{4} theory are analyzed.

*Gusak N.A.*

**The charge grating relaxation in the photorefractive crystals.** pp. 42--44

*Summary:* The equation for describing of the charge grating relaxation in the refractive crystals is obtained and the solution of this equation is found. It is shown that the beginning of the process of the relaxation is described by the Gauss's function transforming to the ordinary exponential at the final stage,

*Makarenko L.F., Lapchuk N.M., Latushko Ya.I.*

**Detection of bistable thermal donors in silicon by EPR technique.** pp. 45--48

*Summary:* It has been shown that bistability of thermal double donors (TDD) in silicon can be observed by EPR-technique. The spectrum of the bistable TDD species (TDD-2) has been isolated using heat-treatment of Czochralsky-grown *n*-type silicon crystals with initial resistivity 4.5 W•cm, at temperatures 400 °C and subsequent irradiation with electrons (*E* = 3.5 MeV). The principal values of the TDD-2 *g*-tensor are determined: *g*_{1} = 1.9928, *g*_{2} = 2.0009, *g*_{3} = 1.9999. Variation of the TDD *g*-tensor is presumed to be due to the defect growth along the *g*_{1} [100]- direction.

*Khalyavin D.D., Lobanovsky L.S., Yarunichev V.P., Troyanchuk I.O.*

**Magnetic resistance effect in monocrystals La**_{0.74}Ba_{0.26}(Mn_{1-x}Co_{x})O_{3} (0.12 £ x £ 0.22). pp. 49--52

*Summary:* Single crystals of La_{0.74}Ba_{0.26}(Mn_{1-x}Co_{x})O_{3} (0.12 £ x £ 0.22) perovskites have been obtained. All the crystals exhibit a jump of resistivity and peak of magnetoresistance around *T*_{c}. The low temperature phase transforms from metallic to semiconducting state with increasing cobalt content, while magnetoresistance tends to rise in spite of metal-semiconductor transition. Anomalous behavior of magnetization was found to be determined by structural modifications.

*Vaskov D.G., Makovetsky G.I., Yanushkevich K.I.*

**Solid solutions of Co**_{x}Ni_{1-x}Te (0 £ x £ 1) and their structural characteristics. pp. 53--55

*Summary:* Solid-solutions Co_{x}Ni_{1-x}Te were synthesized. The continuous solid-solution series with NiAs-type structure was shown to be formed in the Co_{x}Ni_{1-x}Te system using *X*-ray diffraction analysis and density measurements.

**ХИМИЯ**

*Avlasevich Yu.S., Knyukshto V.N., Solovyov K.N.*
**Copolymer of N-isopropylacrylamide and 5-(4-acryloyloxyphenyl)-10,15,20-triphenylporphyrin.** pp. 56--59

*Summary:* Water-soluble copolymer of N-isopropylacrylamide and 5-(4-acryloyloxyphenyl)-10,15,20-triphenylporphyrin and its Zn-containing analog have been synthesized. Absorbance curves of polymer aqueous solutions as a function of temperature have been studied. Absorption spectra of water and methanol solutions of polymers are presented.

*Martsinkevich A.A., Prokopchuk N.R., Krutko E.T., Shiroky V.L., Paplevko I.G.*

**New polyimide modifier.** pp. 60--61

*Summary:* The possibility of considerable improvement of stress-strain and thermal properties of polyimide films by regulating cross-linked structure of polyimide with modistier hexafluorophosphatecobaltitsinium is shown.

*Ivashkevich O.A., Gaponik P.N., Matulis Vadim E., Matulis Vitaly E.*

**Quantum chemical investigation of electron and spatial stucture of 2-(1-methylvinyl)tetrazoles.** pp. 62--65

*Summary:* Quantum chemical and spectroscopic studies of the electron structure and rotational isomerisation of novel tetrazole-containing monomers including 2-(1-methylvinyl)tetrazole, 2-(1-methylvinyl)-5-methyltetrazole, 2-(1-methylvinyl)-5-phenyltetrazole have been carried out. Quantum chemical calculations at the 6-31G**//AMI and 6-31G**//STO-3G levels and spectroscopic data indicate that electron-density distribution in isopropenyl group does not substantially depend on the nature of substituent in the tetrazole ring. Energies of internal rotation and equilibrium content of S-cis- and S-transconformers have been calculated. The data of calculations along with coupling constant values in ^{13}C NMR spectra indicate that laekof spatial interaction between isopropenyl group and substituent in the position "5" of the tetrazole ring is lack. The obtained data allow to suppose that the considered 2-(1-methylvinyl)tetrazoles should be characterized by similar reactivity in the radical polymerization processes.

**БИОЛОГИЯ**

*Ipatyev V.A., Bulko N.I.*
**Antagonism and dilution effects reducing radionuclide uptake by Pinus sylvestris.** pp. 66--68

*Summary:* The paper reports results of an experiment specially designed to decrease ^{137}Cs and ^{90}Sr accumulation levels in Pinus silvestris through enriching radionuclide-contaminated soil with nutrients. It is determined that the effect of "antagonism" plays a crucial role in blocking root supply of ^{137}Cs into trees, while the dilution effect is of prime importance for preventing root uptake of ^{90}Sr. The paper demonstrates it is incorrect to transfer mechanically results of the studies on growing clean agricultural products to forests.

*Kraskovski G.V., Migolenya T.I., Pashatskaya T.V., Lipskaya M.V.*

**Specific reaction of complex of free tumour antigens of the tumour carriers serum with serum antibodies of spleen lymphoid cells recipients of mice-homologic tumour carriers.** pp. 69--72

*Summary:* It is established that serum intact recipient of mice-tumourcarriers spleen lymphoid cells maintains set of isoantibodies, which specific reacts to complex of free serum tumoural antigens of the same tumour carriers. Antibodies, which are produced by lymphoid cells (removed from tumourcarrier organism) on abolition of oncotolerance, can be used for tumour type diagnostics and determination.

*Yakushev B.I., Budkevich T.A., Zabolotny A.I., Mironov V.P., Kudryashov V.P., Yaroshevich O.I., Zhuk I.V.*

**Americium-241 in vegetation of natural biocenoses and agrocenoses at Belarus territories contaminated with Chernobyl fall-out.** pp. 73--76

*Summary:* As a result of b-decay of ^{241}Pu, the content of ^{241}Am increases progressively in soils, contaminated with Chernobyl TUE. Sofar ^{241}Am displayed higher (0.5-1.5-fold) biological mobility than isotopes of ^{239,240}Pu. Activity of ^{241}Am in surface phytomass of wild and cultural plants varies from 0.04 to 5.9 Bq • kg^{-1} of dry weight. ^{241}Am contribution to the total TUE contamination of plants made up 60-80% in 1996-1998. Ficed trials in the areas adjacent to the 30-km zone showed that mobility of ^{241}Am and plutonium was 5-15 times as high as in the zone.

*Sidorovich E.A., Sergeychik S.A., Sergeychik A.A.*

**Effect of sulphur dioxide on physiological-biochemical characteristics of assimilation in Pinus sylvestris.** pp. 77--79

*Summary:* Sulphur build-up in pine needles of Pinus sylvestris from 0.11 to 0.17% negatively affects basic physiological processes, photosynthetic reactions, pigment and protein levels, N:S:P ratios. These changes are factors destabilizing forest ecosystems in Belarus.

*Soltanov V.V., Borisov O.L.*

**Effect of ischemia-reperfusion of small intestine on efferent activity of skin neurons N.Saphenus.** pp. 80--82

*Summary:* Experiments in rats showed that small intestine ischemia and reperfusion led to enhancement of sympathetic efferent activity in n. saphenus skin branches. In conditions of small intestine denervation, sympathetic efferent discharge remained unchanged during ischaemia, but it increased with reperfusion. The latter fact suggests occurrence of humoral influences from the jejunum on the activity of skin supplying sympathetic neurons.

*Bazhanov D.P., Bazhanova A.A., Urbanovich O.Yu.*

**Mutants of nitrogen-fixing bacterium Pseudomonas sp.418 defective in root colonization: isolation and phenotype characterization.** pp. 83--86

*Summary:* Mutants of nitrogen-fixing rhizosphere bacterium Pseudomonas sp.418, losing the ability to colonize competitively barley roots, were isolated by random Tn5 mutagenesis. A Southern blot analysis indicated single insertions of Tn5 in eight mutants. In two mutants Tn5 inserted twice into different DNA regions. The mutants were characterized and defects of adaptive characters were observed: reduced attachment to root surface, impaired chemotaxis, defects in motility, caused by non-production of flagella or non-separation of cells after division, alterations in exopolysaccharide production. As a rule, effect of Tn5 insertions was pleiotropic.

*Yeliashevich N.V.*

**Weather-induced variability of **^{137}Cs content in overground part of automorphic soil plants. pp. 87--90

*Summary:* Daily variability of specific ^{137}Cs content in plants (12 species) in summer time under the influence of climatic factors is shown. The rise of residual solar radiation (exceeding 2 MJ/m^{2}, day) and average diurnal temperature over 10-15 °C (for different species) induced decrease; precipitatioris -- induce increase in activity of overground phytomass. A threshold and thresholdless type of ^{137}Cs build up was recorded at higher daily fall-out. Critical sum of diurnal precipatation for the latter case in 5 species (Agropyron repens (L.) P. B., Bromus inermis Leyss., Origanum vulgare L., Festuca arundinacea Shreb., Acer platanoides L.) is in the range of 20-25 mm.

*Sokolik A.I.*

**Lateral segregation of ion transport mechanisms on plasmalemma and regulation of ionic flow between plant cell and environment.** pp. 91--94

*Summary:* The model of interaction and regulation of plasmalemma ion-transport mechanisms, based on assumption of spatial heterogeneity of the electric field on membrane, was proposed. Heterogeneity is the result of basic ion transport mechanisms - ionic channels of different types, H-ATPase pump, fixed surface charge assumed to be located separately on plasmalemma because of discrete nature of the forming molecular structures and homogeneously distributed plasmalemma non-selective ionic leakage. The coefficients of steady state distribution of Na^{+}, Cs^{+} and S^{2+} in cell and environment as a function of plasmalemma potential difference were calculated. Theoretical and experimental values agree well in reasonable range.

**НАУКИ О ЗЕМЛЕ**

*Anoshko Ya.I., Bordon V.E., Matveyev A.V., Olkhovik E.T.*
**Possibility of heavy mineral prospecting in Anthropogene deposits of Belarus.** pp. 95--98

*Summary:* Results of mineralogical studies of Anthropogene deposits presented in the paper suggest that heavy mineral concentrations may be high enough, which undeniably is of prospecting interest. Background contents for the sum of heavy minerals have been determined and where their anomalous concentration areas have been outlined. The Molodechno and Gorodok areas may be primarily regarded as promising for heavy minerals, and the arrangement of specialized prospection seems expedient.

*Garetsky R.G., Konishchev V.S., Kovchuto A.M.*

**Distribution of salt uplifts in Pripyat--Dnieper--Donetz avlacogen.** pp. 99--102

*Summary:* It is shown that most salt uplifts of the Pripyat--Dnieper--Donetz avlacogen adjacent to faults are of the first generation. Only some are superimposed and therefore may be classified as salt uplifts of the second generation.

*Naidenkov I.V., Arkhipova A.A.*

**New data on stratigraphic scheme of crystalline basement in Belarus.** pp. 103--106

*Summary:* The new version of stratigraphic scheme of Early Precambrian rocks, of crystalline basement structure in Belarus and 20 year geochronometric data is presented. The suggested version is distinguished from the scheme approved in 1982, mainly, by presence of subdivisions including stratified series of amphibolite facies, and by more detailed differentiation of magmatic and ultrametamorphic complexes.

*Volchek N.L., Zhuchkevich V.V., Krasinskaya N.G., Krasovsky A.N., Lyudchik A.M., Turyshev L.N.*

**Atmospheric ozone climatic norm for Belarus and ozone behaviour in 1998-1999.** pp. 107--110

*Summary:* Total atmospheric ozone climatic norm for Belarus has been revised using data obtained in 1994--1997 with the PION spectrometer-ozonometer. Anomalous behavior of total ozone in 1998-1999 is discussed.

*Taran L.N., Varaksa V.V.*

**Black schist complex in south-eastern part of Belarusian crystalline massif.** pp. 111--113

*Summary:* Horizons of graphite-bearing gneisses and schists distinguished in the southeastern part of the Belarusian crystalline massif are included into Okolovo metavolcanic-sedimentary series. Prospecting of graphite-bearing gneisses and schists for platinum-group elements and gold is defined by 1) sedimentary origin of graphitic rocks, 2) their space compatibility with deep fault and granite intrusions which promoted forming of the graphite- and sulphide-rich metasomatites, 3) abundance of sulphides and specific association of elements (Cu, Zn, Pb, Mo, As, Ag).

**ТЕХНИЧЕСКИЕ НАУКИ**

*Andrizhievsky A.A., Loukashevich A.G., Mikhalevich A.A., Trifonov A.G.*
**Simulation of interaction between vapour-droplet wastes and aerosol discharges of power units.** pp. 114--117

*Summary:* Sources of possible technogenic contamination of atmosphere near power units have been considered. The technique of estimating potential interaction of wet cooler plumes with power unit discharges and other atmospheric pollututants is presented. The method based on software complex RELEASE comprises models describing dynamics of close-tosurface migration of technogenic impurities in aerosphere. Results of simulation experiments as applied to analysis of cooler emission effect on aerosol wastes of nuclear power unit ventilation system have been provided.

*Yashcheritzin P.I., Akulovich L.M., Rakomsin A.P., Kozhuro L.M., Mrochek Zh.A.*

**Thermodynamic impact control in the course of electromagnetic surfacing.** pp. 118--121

*Summary:* It is shown that adaptive controlof electromagnetic surfacing ensures stability of technological system.

/ Издания академии / Научные журналы / К началу страницы

Разработана и поддерживается Николаем Н. Костюковичем. Последнее обновление: *6 сентября 2008 г.*

Создана при участии Игнатия И. Корсака

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