Vol 17, No 5 (2011)
- Year: 2011
- Articles: 21
- URL: https://journals.ssau.ru/est/issue/view/234
Articles
UNIQUENESS OF POSITIVE RADIAL-SYMMETRICAL SOLUTION OF DIRICHLET PROBLEM IN ANNULAR DOMAINS FOR ONE CLASS OF NONLINEAR DIFFERENTIAL EQUATIONS OF THE SECOND ORDER
Abstract
The existence and uniqueness of positive radially symmetric solution of Dirichlet problem in annular domain for one class of nonlinear differential equations of the second order is proved.
ON A CERTAIN PROBLEM FOR A WAVE EQUATION
Abstract
In this paper a hyperbolic equation with non-classical boundary conditions
for a hyperbolic equation is studied. This problem can be viewed as the gener
alization of the problem about the oscillation of the string if it ends experience
the resistance of medium. The unique solvability of the problem is proved. The
prove of solvability is based on the received a priory estimates in Sobolev space.
THE MACKAY’S FUNCTIONS AND ELEMENTARY ABELIAN 2-GROUPS
Abstract
In the article we consider the problem of finding finite groups such that all their elements can be associated with multiplicative ´-functions. We solve this problem for elementary Abelian 2-groups.
ON CERTAIN NONLOCAL PROBLEM FOR HYPERBOLIC EQUATION WITH INTEGRAL CONDITIONS OF THE FIRST KIND
Abstract
In this article, we consider a nonlocal problem for hyperbolic equation with integral conditions of the first kind. The main goal of this article is to show the method which allows to reduce posed problem to the problem with integral condition of the second kind. Existence and uniqueness of generalized solution is proved.
ABOUT THE METHOD OF TRACES OF RESOLVENTS CALCULATED PRECISELY
Abstract
In the article it is ascertained that there are some methods of calculation of eigenvalues of ordinary boundary problems for the equations of mathematical
physics. If the positive degree of a resolvent is the kernel operator this can take
advantage at calculation of a spectrum of a boundary problem. It is mentioned
that similar results are reached by A.A. Dorodnitsyn
ON ONE APPROXIMATION ESTIMATE
Abstract
Linear operators satisfying some conditions are considered. The given operators are a particular kind of class operators (by P.P. Korovkin). For the estimate derivation the interpolation method is used, described in the works by Yu.G. Abakumov and O.N. Shestakova
REPRESENTATION OF PARSEVAL FRAMES IN HILBERT SPACES
Abstract
In this paper we introduce two new classes of Parseval frames in arbitrary
Hilbert spaces of finite or infinite dimension: simple and composite Parseval
frames. Theorems of representation of composite Parseval frames by summation
of simple ones are proved. Few classes of simple frames are described: orthonor
mal basis, equiangular Parseval frames and some other examples.
ON SEVERAL VARIETIES OF LEIBNIZ ALGEBRAS
Abstract
The paper is devoted to two new results concerning varieties of Leibniz alge
bras. In case of prime characteristic p we construct an example of a non-nilpo
tent variety of Leibniz algebras with Engel condition. In case of field of character
istic zero we obtain a new result concerning the space of multilinear components
of the variety of left-nilpotent Leibniz algebra of class three.
INTEGRAL MANIFOLDS AND THE REDUCTION PRINCIPLE
Abstract
The paper is devoted to the application of geometric decomposition method
to the order reduction of problems of stability under persistent disturbances
and input-to-state stability.
SIMULATION OF TRANSPORT PHENOMENA OF FULLERENES IN THE FLUID BY METHOD OF MOLECULAR DYNAMICS
Abstract
In the frameworks of classical molecular dynamics method the coefficients of
diffusion and viscosity of fullerenes in fluid (benzol) depending on the tempera
ture of nanosuspension have been calculated.The effective potential of fullerene
molecule interaction used in calculations is obtained under the assumption of
additivity of fullerene and fluid molecules interaction, where fullerene is consid
ered as a solid particle.
ASYMPTOTIC TECHNIQUE FOR THE SOLUTION OF FRACTIONAL EQUATION FOR GROUND-WATER CONTAMINATION MIGRATION
Abstract
A new technique for defining ground-water asymptotic movement using spe
cific properties of fractional derivatives is introduced in this article. Advantage
of the given technique in comparison with traditional techniques used for the
analysis of such processes is based on the fact that preliminary definition of
contamination concentration at every moment and at each point of stabilization
area is not necessary.
ENTANGLEMENT IN NONDEGENERATE TWO-PHOTON TAVIS - CUMMINGS MODEL
Abstract
The influence of dipole-dipole interaction on the entanglement between two
atoms with different initial W-like states in Tavis Cummings model with
degenerate two-photon transitions has been investigated. The results show that
the dipole-dipole interaction leads to the stabilization of atomic entanglement.
PHOTOSENSITIVE MATRIX BASED ON POROUS MICROCRYSTALLINE SILICON
Abstract
The article presents the results of experimental researches of optoelectric properties of porous silicon. Layers of porous silicon were formed using electrochemical etching process in water-alcohol solutions of hydrofluoric acid on plates with a pre-established microrelief surface. Evaluation of possibility of using of created structure as the artificial retina component was performed based on the results of the research.
SYNTHESIS OF 1,2;3,4-DI-O-ISOPROPYLIDENE-6- O-[4-(1H-AZOL-1-YLMETHYL) PHENYL]- ¯-D-GALACTOPYRANOSE AND 1,2,3,4-TETRA-O-ACETYL-6- O-[4-(1H-AZOL-1- YLMETHYL)PHENYL]-¯-D-GLUCOPYRANOSE
Abstract
Derivatives of D-galactose and D-glucose substituted for the primary hydrox
yl group, which contain an aglycone azolylmethylphenyl fragments (for imida
zole, 1,2,4-triazole, benzimidazole and benzotriazole) has been synthesized. To
protect the secondary hydroxyl groups of monosaccharides acetyl and isopropy
lidene groups were used.
DETERMINATION OF THE CONTENT OF HEAVY METALS IN LIQUID PHASE OF SNOW BY X-RAY FLORESCENSE METHOD
Abstract
The possibility of determining the total content of heavy metals in the liquid phase of snow was researched by X-ray fluorescence analysis with preconcentra tion of elements determined by sorption DETATA filters. Optimal conditions for the analysis, providing a minimum error of determination have been chosen and justified. The contribution was made by the stage of concentration in the overall error of the method. A pollution monitoring of snow cover in the five districts of Samara was carried out.
1,4-BENZOQUINONE DERIVATIVES AS INHIBITORS OF CORROSION AND HYDROGEN ABSORPTION OF STEEL AT PRESENCE OF SRB
Abstract
The results of study of the derivatives of 1,4-hydroquinone as inhibitors of
microbiological corrosion and hydrogen absorption of mild steel in a water-salt
media supporting the development of sulphate reducing bacteria (SRB) and
close by its composition to the sea water containing biogenic hydrogen sulphide.
Content of H2S, bacterial titre in the corrosive meas well as its pH, Eh and
potential of steel '; were determined together with the quantity of hydrogen
absorbed by surface layers of steel. Protective efficiency of the best studied
species from corrosion reaches 65...84 %, as for their action against hydrogen
absorption by steel specimen 60...72 %. The decrease of the number of SRB
cells due to the action of the derivatives of 1,4-hydroquinone was found to be
48...84 %, while the suppression degree 29...57 % (at the concentration of
5 mMol/L).
Key words:
SOME CHEMICAL CHARACTERISTICS OF BARK AS A SUBSTRATE FOR LICHEN’S DEVELOPING (KRASNOSAMARSKY FOREST AS AN EXAMPLE)
Abstract
On the one hand, there are some nitrate, nitrite and ammonium substances
in the bark which are very important for lichen’s developing. On the other hand,
genetic proton components limit the growth of lichens. Phenol substances which
are present in the bark of trees are indifferent for lichen’s developing.
THE ESTIMATE OF PERSPECTIVENESS OF INTRODUCTION OF SOME NORTH-AMERICAN SPECIES OF FAMILY ROSACEAE JUSS IN THE ARBORETUM OF MOUNTAIN-TAIGA STATION OF FAR-EASTERN BRANCH OF THE RUSSIAN ACADEMY OF SCIENCES
Abstract
The estimate of perspectiveness of 20 species of North-American trees and
bushes of the family of Rosaceae which are cultivated in the arboretum of
Mountain-Taiga station of FEB RAS. Higher indicators (96–97 points) have
Amelanchier spicata, A. alnifolia, Aronia melanocarpa, Physocarpus opulifolia,
P. monogynus, P. capitatus, Prunus americana, Rubus odoratus, Rubus occiden
talis. Quite perspective (82–90 points) are Cerasus besseyi, Crataegus flabellate,
C. macracantha, C. rotundifolia, C. submollis, Padus pensylvanica, P. serotina,
P virginiana, Rosa nutcana, Sorbus americana. Less perspective (67 points) and
demanding further study is Rosa Palnstris.
DATA ABOUT MORPHOLOGY AND BIOLOGY OF BENTOPHILUS STELLATUS (SAUVAGE, 1874) OF KUIBYSHEV RESERVOIR
Abstract
According to the data received in 2003–2004 years results of morphology and
reproduction characteristics of Bentophilus Stellatus from Ulyanovsk stretch of
Kuibyshev Reservoir are given, size-age structure, qualitative and quantitative
food composition are considered.