# Доклады Академии наук Беларуси, 1996, Том 40, No.5

/ Издания академии / Научные журналы

Доклады Академии наук Беларуси, 1996, Том 40, No.5

## СОДЕРЖАНИЕ

**МАТЕМАТИКА**

*Gaishun I.V., Astrovsky A.I.*
**Description of the set of uniformly observable linear time-varying systems.** pp. 5--8

*Summary:* The notion of uniform observability in terms of output functions is proposed for linear time-varying systems of ordinary differential equations. The precise description of the set of systems to be uniformly observable is obtained. The necessary and sufficient condition of uniform observability is established. The parametrization of the orbits, on which the set of uniformly observable systems is decomposed under the action of the group of linear time-varying transformations of class *C*^{1}, is given.

*Samarsky A.A., Vabishchevich P.N., Matus P.P.*

**Difference schemes of increased order of approximation on irregular grids for elliptic equations.** pp. 9--14

*Summary:* Monotone conservative schemes of the second order of local approximation are constructed for multidimensional Poisson equation on irregular grid. Stability of the scheme with respect to boundary conditions and the right side was proved on the basis of the principle of maximum and accuracy estimates of the method were obtained in the norm *C*.

*Artyugin V.G., Monastyrny P.I.*

**On alternating triangular method with resolution of the main matrix part of the system.** pp. 15--19

*Summary:* A new approach to building inexplicit two-step iteration processes is suggested. Justification of the suggested alternating triangular (*r*) method is given, its convergence is proved and the analysis of its basic properties is carried out.

*Yerovenko V.A.*

**Essential Weyl's spectrum for analytic functions of bounded operators on Banach space.** pp. 20--24

*Summary:* We give some generalizations of the Weyl's theorem on essential spectrum for analytic functions of isoloid bounded linear operators on a Banach space.

*Lazakovich N.V., Stashulenok S.P.*

**Approximation of stochastic integrals and solutions of differential equations in direct product of algebras of generalized stochastic processes.** pp. 25--30

*Summary:* The differential equations are considered in the direct product of algebras of generalized random processes and their associate solutions which in some cases are solutions of the corresponding stochastic differential equations of Ito and in others -- solutions of the equations of Stratonovich are investigated.

*Volkov I.A.*

**On upper uniform indices of two-dimensional quasi-linear system.** pp. 31--35

*Summary:* It was proved that the cardinality of the set of upper uniform indices of quasi-linear differential system of order *n* with higher order perturbation and the diagonal system of the first approximation is greater than 2^{n} - 1.

*Leonov N.N.*

**Measures on compact ultrametric spaces.** pp. 36--39

*Summary:* Various constructions of measures on compact ultrametric spaces are investigated.

*Lebedev A.V.*

**Quasi-crossed products and the isomorphism theorem for ***C**-algebras associated with quasi-representations of discrete groups. pp. 40-43

*Summary:* The structure which is a natural analogue to the classical cross-product is introduced a studied for a given quasi-representation of a group by automorphisms of a *C**-algebra.

*Shavel N.A.*

**To the 3/2 stability theorem for a scalar delay differential equation.** pp. 44--48

*Summary:* For scalar delay differential equation sufficient conditions of the stability and asymptotic stability are obtained, relaxing the 3/2 stability theorem requirements.

**ФИЗИКА**

*Korshunov F.P., Zhdanovich N.E., Marchenko I.G., Troshchinsky V.T.*
**Formation efficiency of the thermostable recombination centres in irradiated silicon ***p-n*-structures. pp. 49--53

*Summary:* The results of the investigation of the formation efficiency of the thermostable (>400^{°} C) recombination centres of the minority charge carriers in silicon *p-n*-structures on cruisable-grows Si (r = 30 -- 40 Om · cm) depending on electron fluence (*E* = 4 MeV, *F* = 10^{15}--10^{17} m^{-2}), annealing temperature (400 -- 600^{°} C) and annealing time (1 -- 120 min) are submitted in this work. It is established, that the formation efficiency of the recombination centres grows with fluence increase in annealing temperatures range of 400 -- 450^{°} C at *F* > 3 · 10^{15} cm^{-2} and decrease in annealing temperatures range of 500 -- 600^{°} C at *F* > 5 · 10^{15} cm^{-2}. Isothermal annealing of the recombination centres proceeds at all temperatures at least with two activation energies.

*Matyunina O.V., Pogrebnyakov A.V.*

**Heat effects in YBa**_{2}Cu_{3}O_{7-x} microbridges. pp. 54--57

*Summary:* Hysteresis of current-voltage characteristics of YBa_{2}Cu_{3}O_{7-x} thin film microbridges (length up to 5 µm) which were formed in the strips having the width of 20 µm and the length of 250 µm is shown to be attributed to the self-heating effects. The value of heat transfer coefficient a was deduced from the experimental data: a = 5500 W/(cm^{2} · K).

*Grushevskaya G.V., Gursky L.I., Komarov L.I., Krylov G.G.*

**Atomic ellipsoids as a form of deformed shells of solids.** pp. 58--64

*Summary:* The method for calculation of temperature Green functions corrections of Fermi system which are caused by the non-sphericity of the potential of the crystal electron subsystem has been proposed. The possibility of using the scattering waves method for calculation of energetic parameters of solid state clusters where the atoms are approximated by the scattering ellipsoids has been demonstrated.

**ХИМИЯ**

*Soldatov V, S., Gogolinsky V.I., Zelenkovsky V.M., Pushkarchuk A.L.*
**The influence of the cross-links structure of sulphopolystyrene cation exchangers on spatial distribution of sulphonic groups.** pp. 65--69

*Summary:* Distribution of probabilities for existing different local concentrations of the functional groups in sulphonated polystyrene has been studied. The following two types of fragments have been selected to represent the polymer structure: *H*-shaped and *T*-shaped fragments.

*Konoplya N.A., Kuzmitsky B.B., Lakhvich F.A., Nasek V.M.*

**Some design aspects of immunomodulating drugs based on heterocyclic steroid analogues.** pp. 70--73

*Summary:* At present a store of a low molecular weight compounds used as immunomodulating drugs in clinical practice is scanty. That is why a purposeful search for the immunoactive substances is expedient. The substances in question are represented by natural carbocyclic steroid analogues containing a nitrogen atom (substituted for the carbon one) in the 8th position of steroid frame. When estimated in terms of immunopharmacological capacities, 8-azasteroids appear to be rather promising. The carried out research provided the opportunity to estimate the structural and functional relations that determined the direction and extent of 8-azasteroid immunotropic action.

*Levchik G.F., Levchik S.V., Lesnikovich A.I.*

**Mechanism of action of complex flame retardants in polyamide 6: ammonium polyphosphate -- inorganic filler.** pp. 74--77

*Summary:* Inorganic fillers improve the fire retardant action of ammonium polyphosphate in polyamide 6. Without interfering the interaction between ammonium polyphosphate and polyamide the fillers react with formed polyphosphoric acids increasing the yield of solid residue. If the optimum ratio between ammonium polyphosphate and filler is found, the glass-like intumescent layer is formed on the surface of burning polymer which proofs the polymer against heat flux of the flame and hinders diffusion of combustible gases to the flame and oxygen to the polymer surface.

**БИОЛОГИЯ**

*Goncharenko G, G., Padutov A.E., Khotyleva L.V.*
**Construction of genetic maps for four pine species forming forests in Eastern Europe.** pp. 78--83

*Summary:* In the analysis of 21 allozyme genes in four Eastern European pine species 41 loci in 12 linkage groups were mapped, 13 genes being localized in 4 linkage groups in *P.sylvestris*, 13 genes in 4 groups in *P.mugo*, 11 genes in 3 groups in *P.nigra* and 4 genes in one group in *P.brutia*. The orders and the locations of genes in the linkage groups in different species were similar. The data show that the genetic arrangement is highly conservative at least in two-needle Eastern European pines.

*Lobanok E.S., Rebeko V.Ya., Kadushina I.B., Vorobei A.V.*

**Change in the endogenous porphyrin content in thyroid gland at different pathology.** pp. 84--86

*Summary:* Variations in fluorescence intensity and the content of endogenous porphyrins in cells and tissue of thyroid gland are revealed on a postoperational material. An increase in the total porphyrins fluorescence and the protoporphyrin content is observed are pathologically changed sites for malignant tumours or adenomas and reduction in the coproporphyrin content -- for goiter.

*Polonetskaya L.M., Maneshina T.V., Sakovich V.I.*

**Study on the influence of ***Fusarium oxysporum* cultural filtrate on callusogenesis in fibre flax. pp. 87--90

*Summary:* The paper present information about the influence of *Fusarium* oxysporum cultural filtrate on callusogenesis and regeneration in fibre flax. A certain agreement of estimates of resistance to *Fusarium* wilt disease in a given collection of varieties under in vivo and in vitro conditions was revealed.

*Mazets Zh.E., Deeva V.P.*

**Kvartazin influence on protein synthesis and qualitative composition in common wheat plants with different genotypes.** pp. 91--95

*Summary:* The influence of spraying by a new plant growth regulator kvartazin (KV) on synthesis and qualitative composition of soluble proteins of euploid and DT-lines of wheat variety Chinese Spring was investigated. Different character of KV action on investigated processes in regard to chromosome state and the post-treatment time was established. It was supposed that KV influenced the gene regulation level of protein synthesis.

**НАУКИ О ЗЕМЛЕ**

*Azhgirevich L.F., Anoshko Ya.I., Rylova T.B., Khursevich G.K., Shimanovich S.L., Yakubovskaya T.V.*
**Stratigraphy of neogenic deposits in Belarus.** pp. 96--100

*Summary:* Three regional horizons (the Brinev, Antopol and Kolochin ones) and eight subhorizons, the age of which is grounded by the complex of paleobotanical methods, are revealed in the proposed stratigraphic scheme.

*Aksamentova N.V.*

**Relationships and formation conditions of AI**_{2}SiO_{5} polymorphic modifications in secondary quartzites of the Zhitkovichi horst. pp. 101--105

*Summary:* The formation conditions of the mineral association of andalusite + kyanite + sillimanite unusual for low-depth metasomatic secondary quartzites are described. It has been concluded that the medium chemical composition was the leading factor of mineral formation which took place at a temperature of 360--400° C (possibly up to 550° C) under isobaric conditions (*P* = 0.5 -- 1.0 kbar).

*Sanko A.F., Moiseev E.I.*

**The first determination of paleomagnetic boundary between Brunhes--Matuyama epochs in the Pleistocene deposits in Belarus.** pp. 106--109

*Summary:* The paleomagnetic boundary between Brunhes--Matuyama epochs was established in the upper part of the Varyazhian horizon deposits in Belarus Eopleistocene.

*Bulkin Yu.S.*

**Characteristic properties of biotite composition of the Early Precambrion paragneisses and metasomatic gneisses of granitization in Belarus.** pp. 110--114

*Summary:* On the basis of characteristic properties of biotite chemical composition it is proved that the most frequently found in the region metasomatic gneisses of granitization emerged due to the rocks of the basic composition.

**ТЕХНИЧЕСКИЕ НАУКИ**

*Tochitsky E.I., Chekan N.M., Grozhik V.A., Yeliseev S.Yu.*
**Properties of lead-borate glassy thin films obtained by the laser deposition method.** pp. 115--119

*Summary:* The results of the investigation of the surfaces morphology and chemical composition of the ternary lead-borate glassy thin films, obtained by the method of laser deposition in vacuum, are presented.

*Kheifets M.L.*

**Cyclicity of surface layer conditions and properties under combined methods of metal treatment.** pp. 120--123

*Summary:* Evolution of the surface layer formation processes was examined in terms of the strained state characteristics presented by stickiness coefficients of the technological and operation surroundings.

/ 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

Копирайт © 1997-2008 Национальная академия наук Беларуси

Копирайт © 1996 Издательство "Беларуская навука"