Source: http://nasb.gov.by/eng/publications/dan/dan54_1.php
Timestamp: 2019-04-19 22:11:18+00:00

Document:
Lemeshevsky S. V., Makarov E. K., Matus P. P.
Summary: The difference analogue of the Bihari lemma allowing one to obtain a priori estimates of the stability with respect to the initial data and the right-hand for solutions of difference schemes for non-linear equations of mathematical physics is proved. The proven lemma assists to determine the point of time after which the singularity of the solution can arise.
Summary: A priori estimates of the stability in the sense of the initial data of the difference scheme approximating polytropic gas equations in the Riemann invariants are obtained. The results of computational experiment confirming the theoretical conclusions are given.
Monastyrnyi P. I., Stelmakh S. N.
Summary: The algorithm of the multiple bilateral shooting for systems of nonlinear ordinary differential equations of second order is prposed, its convergence for the boundary-value problems with the Weiss-isolated solution is proved, direct, multiple and bilateral multiple shootings are compared.
Summary: An autonomous system of two second-order nonlinear differential equations is considered. It is shown that this system is a Painleve-type system. In particular, it is demonstrated that its solution is expressed in terms of solutions of the equation for the simplest polynomial Hamiltonian associated with the second Painleve equation. Other properties of the solutions of this system are considered.
Summary: Quantities for characterization of the locality of imperfectly nested loops are introduced and studied. Conditions for localization of input and intermediate data in virtual processors are obtained.
Summary: This article deals with two state estimation problems that arise in connection with optimal output feedback synthesis problems for linear time-varying deterministic systems subject to bounded disturbances on incomplete measurements. Algorithms for solving problems under consideration are presented.
Summary: A sufficient condition for the stability of Lyapunov's indices of the linear differential system, whose Cauchy matrix at the neighboring points of some arithmetic progression is an upper triangle matrix, is obtained.
Lyakhov D. A., Lomovtsev F. E.
Summary: New theorems of existence, uniqueness and continuous dependence of weak solutions of the Cauchy problem for the second-order hyperbolic differential-operator equation with a variable domain of a smooth unbounded operator coefficient are proved. A new method to prove the uniqueness of weak solutions of hyperbolic differential-operator equations is suggested. Correct solvability in the weak sense of the mixed problem for the wave equation with the time-dependent boundary condition is established.
Rychkov Yu. M., Akimov A. L, Vasilevich A. E., Zaerko D. V., Zaikova S. A.
Summary: In the present work the experimental research of regularities of propagation and localization of electromagnetic waves of microwave frequency in the two-dimensional periodic structure with adjustable parameters is made. The experimental results can be directed to meet the challenges of creating new microwave electronic-controlled devices.
Vlasov R. A., Lemeza A. M.
Summary: Soliton-like solutions are obtained for the two-wave system of Maxwell-Bloch equations that govern the coherent nonlinear interactions of light pulses with a one-dimensional periodic passive resonant medium where the refraction index is spatially modulated and thin layers of resonant particles influenced by the local field are localized at the maxima of the refraction index. It is shown that the phase of the stationary pulse is nonlinearly dependent on the pulse amplitude, which is a consequence of dipole-dipole interactions between closely spaced atoms. It is established that the velocity of the soliton is an ambiguous function of its duration (bistability of second kind).
Kudryashov V. V., Baran A. V.
Summary: The exact wave functions and energy levels are obtained for an electron in a two-dimensional quantum ring with a confining potential of finite depth in the presence of an external magnetic field and the Rashba spin-orbit interaction.
Vorobiov P. D., Cherednichenko D. V., Vorobieva E. V., Krutko N. P., Regino A. V.
Summary: Colloidal properties, adsorption and flocculation ability of cationic polyelectrolytes (acrylamide co-polymers) with different charged groups content were studied in the presence of surfactants. Results showed that the flocculation effectiveness increases when using low-charged cationic flocculants compared to highly-charged ones, the flocculation effectiveness of such polymers does not depend on the presence of surfactants and low molecular salts. These questions are important for practical applications of polymers, e. g., waste water treatment.
Potkin V. L, Malshakova M. V., Belykh D. V., Petkevich S. K, Kutchin A. V.
Summary: The series of chlorine E6 derivatives and polychloro(bromo)carboxylic acid were synthesized. The compounds obtained are of interest for the study of the antitumor activity.
Gerlovsky D. O., Litvinko N. M., Skorostetskaya L. A., Kuchuro S. V., Kalinichenko E. N., Farina A. V.
Summary: A new type of competitive inhibitors of pancreatic phospholipase A2 -- di- and three-phosphoesters of Acyclovir -– has been found. It is shown that a necessary condition for the inhibiting action of this compound is the presence of the aromatic fragment in the effector molecule. 2-(4-(Nitrophenyl)ethyl-phosphate Acyclovir is perspective for a further study as an antipancreatitis remedy of nucleic nature with a softened mode of action.
Halauko Yu. S., Serebryanskaya T. V., Matulis V. E., Gaponik P. N., Ivashkevich O. A.
Summary: Quantum chemical calculations within the framework of DFT were carried out for a set of platinum (II) complexes with nitrogen-containing heterocycles. A physically interpretable QSAR model was developed and a correlation between the biological activity and structural properties was obtained by means of the multiple linear regression method. The range of new tetrazole-containing platinum (II) complexes was synthesized, and their cytotoxic activity was experimentally determined and compared with the values predicted by the QSAR model. Crucial properties of compounds and their relationship with the mode of action were discussed.
Golubev A. P., Bodilovskaya O. A., Slesareva L. E.
Summary: The parameters of growth and reproduction in families of pond snail Lymnaea stagnalis from self-fertilization (SF) and cross-fertilization (CF) in the second and seventh successive generations at grouping and individual rearing have been estimated in laboratory experiments. At the same time a prolonged reproduction by CF led to shortening of the beginning of reproduction by 15-55 days, a decrease of the body mass and total fecundity per lifespan were seen. The average values of the intrinsic population growth of L. stagnalis at both modes of reproduction differed insignificantly and retained at the high level. A minimal period of a two-fold increase of L. stagnalis population abundance at SF and CF amounts to 12-15 and 11-56 days, respectively. Therefore the measures of control of natural nidi of helminth diseases based on the decrease of abundance of L. stagnalis populations seem to be ineffective. A few residuary mollusks reproduced by SF are able to restore the initial abundance of population for a short period of time.
Gorbunova N. В., Ulashchik V. S., Batai L. E., Vodchits A. I., Orlovich V. A.
Summary: The changes in the content and activity of protease inhibitors (a2-macroglobulin and a1-antitripsin) in the blood serum and the liver tissue of new-born rat males after the local thermal influence of high-intensive laser radiation at a wavelength of ~ 2 mm (power density of 45 and 70 W/cm2) were demonstrated.
Beletzky A. V., Nikolaev V. I., Ermakov S. F.
Summary: Proceeding from the experimental studies with a cartilage-on-cartilage friction pair using pendulum tribometry a difference has been established in the influence of medicinal preparations based on hyaluronates and chondroitin sulfate upon blood serum lubricity. It is proved that during the cartilage-on-cartilage friction interaction the best tribiological characteristics in the complex of blood serum, which practically coincide with those of natural synovial fluid, provide medicinal preparations based on chondroitin sulfate.
Summary: A new concept of scientific assessment and analysis of the competitiveness of the international economy on the basis of self-organization is offered. The approach is practically tested for the Republic of Belarus and 94 countries of the world community. Conclusions are made.
Summary: This article proposes a method of estimation of the effectiveness of procurement activities and an integrated indicator, developed on the basis of fundamental principles of international public procurement. The author developed a method of ranking the organizations according to the results of the effectiveness of procurement process. There are calculations of the integrated indicator of the effectiveness of procurement and the rate of agencies according to the results of the effectiveness of procurement process in 2008.
Summary: In the article, the system of principles is determined for the first time. The upholding of these principles in complex allows attaining stable food safety and balanced food supply of the country.
Tsyganov A. R., Vildflush I. R., Batyrshaev E. M.
Summary: In the article the information about the influence of separate and complex usage of mineral fertilizers and plant protection means on the intensity of productive processes, yield and quality of grain by cultivation of winter wheat is presented.

References: V. 
 V.

 V.

 V. 
 V.

 V.

 V. 
 V. 
 V. 
 V.