Доклады Академии наук Республики Таджикистан, том 62, №09-10, 2019 г.
|Article title and abstract||Pages|
On the distribution of the fractional parts of a quadratic polynomial whose argument runs through primes
from a short interval
The problem of the distribution of the fractional parts of a quadratic polynomial whose argument runs over primes from an interval of small length is reduced to estimates of the sums of square exponential sums over primes in short intervals.
Key words: uniform distribution; exponential sums over primes in short intervals; deviation of sequence members.
On approximation of periodic differentiated functions
in space L
In this paper the sharp constants in Jackson-Stechkin type inequalities for the given characteristic of smoothness defined by averaged values of norms with finite difference of m-th order of function f in space L was found.
Key words: the best polynomial approximation; finite difference of m-th order; partial sum of Fourier sum; Jackson-Stechkin type inequality.
|Muhamadiev E.M., Sharifzoda Z.I., Nurov I.J.|
The qualitative analysis of nonlinear equation of the photosynthes
In this article the existence solutions of the nonlinear system of the problem photosynthesis is considered. The conditions of the existence solutions and shown the behavior of the nonlinear system with respect to stationary solutions were found.
Key words: nonlinear differential equation; stationary solution; phase portrait; linearization; stability.
Оn separability and coercive solvability of second-order nonlinear differential equations in the Hilbert space
The work focuses on obtaining coercive estimates and separability theorems of second-order nonlinear differential operators. Based on the obtained coercive estimates, the coercive solvability of the second-order nonlinear differential equations in the space is investigated.
Key words: differential operator; coercive estimates; nonlinearity; separability; solvability; Hilbert space.
|Pirov R., Rakhimzoda F.Sh.|
The research of issues of jointness and the manifolds
of solutions of a class of nonlinear overdetermined systems of five differential equations with three unknown functions in space
A class of nonlinear systems with three unknown functions is considered. Explicit compatibility conditions are obtained that provide unambiguous solvability of problems with initial data.
Key words: overdetermined systems; compatibility condition; manifold solut.
|Rajabova L.N., Khushvakhtov M.B.|
About some cases of non-model two-dimensional integral equations of a volterra type with a special and weakly special line on a strip
In this article, we investigate a non-model two-dimensional Volterra integral equation with a singular and weakly singular line on the strip. In the case where the functions present in the nuclei are unrelated, the solution of a non-model two-dimensional Volterra-type integral equation with a singular and weakly singular line is reduced to the solution of a two-dimensional integral equation with a weak singularity on the band. The solution of the integral equation is expressed in terms of the resolvent of the integral equation with a weak singularity.
Key words: non-model integral equation; weak-singular line; singular line; resolvent.
|Kokhirova G.I., Husarik M., Kartashova A., Ivanova O., Bakanas E., Sokolov I., Khamroev U.Kh., Buriev A.M.|
Results of quasisynchronous observations of asteroid Phaethon
Complex joint observations of asteroid (3200) Phaethon were performed by using small and middle telescopes during period of its approach to the Earth in 2017. The main aim of photometric observations of the asteroid was searching for its low-level cometary activity (possible coma and/or dust tail) in pre-perihelion passage. We performed observational runs with telescopes ranging from 0.61-m to 2-m and BVR color imaging. Three longer photometric series we used for modeling of 3D shape of Phaethon. The color indices and size of the asteroid were estimated. As a result of astrometric reduction of observational data the coordinates and trajectory of asteroid were determined. However the cometary activity of Phaethon was not detected.
Key words: observations; asteroid; photometry; astrometry; size; color index; shape; position.
|Solikhov D.K., Khobilov D.U., Odilov O.Sh.|
On the numerical calculation of the reflection coefficient in the theory of forced scattering of Mandelstam-Brilluin in a homogeneous plasma
The problem of stimulated Mandelstam-Brilluin scattering (SMBS) in a homogeneous plasma is considered in the approximation of strong dissipation of sound waves, taking into account the nonlinearity of the second harmonic and depletion of the pump wave. It is shown that the simultaneous consideration of two nonlinearity in a homogeneous plasma will lead to a decrease in the reflection coefficient.
Key words: stimulated Raman scattering: WRC; SMBS; SBS; SRS; ion sound; strong dissipation approximation.
|Salikhov T.Kh., Ismatov T.N.|
Temperature field of metals in the field of the gaussian pulse of the ion beam by the "radical" interaction model
Within the framework of the assumption of a "radical" model of the interaction of an ion beam with metals, the features of the formation of a non-stationary temperature field in metals Cu, Au and Ag in the field of a Gaussian pulse of an ion beam are theoretically studied. The necessary expression which describing the space-time distribution of temperature field for the considered case is obtained.
Key words: metal; ion; ion beam; thermal spike model.
|Abdusalyamova M.N., Barotov S.S., Makhmudov F.A., Shaimardanov E.N.|
Obtaining and properties of nanostructured tulia oxide
Nanostructured thulium oxide (TmO) using the method of thermal decomposition of rare-earth metal compounds was synthesized. Thulium chloride, acetate and thromium carbamide were chosen as precursors. The obtained powders were characterized by the methods of elemental analysis, X-ray phase analysis (XRF), infrared (IR) spectroscopy, thermal analysis (TA) and Raman spectroscopy (RS).
Key words: properties nanostructured thulium oxide; RFS; IR-spectroscopy.
|Juraev T.D., Nurov K.B., Nimonov R.A., Mirzoeva B.M., Kurbonov Sh.B., Sodikova S.S.|
Thermodynamic estimation of the interaction of carbon with gold, silver, cadmium and zinc
The interaction in the binary systems of gold, silver, cadmium and zinc with carbon is investigated. By the method of thermodynamic analysis for the first time, complete calculation diagrams of the state of these systems were constructed. They found the absence of interaction between the components in both the liquid and solid states.
Key words: gold; silver; cadmium; zinc; carbon; state diagram; thermodynamic assessment; interaction; delamination.
|Salimov А.М., Sharopov F.S., Sangov Z.G., Мirzoev S.О., Salimov Т.М., Haidarov К.H.|
The antimicrobial activity of the essential oil
of Аrtemisia annua growing in Tajikistan
Antimicrobial activity of essential oil of Artemisia annua L.. grown in Tajikistan are investigated. The antimicrobial activity of the essential oil was studied in comparison with the essential oil of common oregano. For study the antimicrobial activity. daily cultures of microorganisms of the museum strains Staphylococcus aureus ATCC 6538-P. Pseudomonas aeruginosa HISC 453. Salmonella abony IHE 103/39 and isolated strains of Pasterella and Escherichia coli were used. The microbial load was 0.5 million cells / ml. It is shown that the essential oil of Artemisia annua has a high antimicrobial activity against strains Staphylococcus aureus. P. aeruginosa. Pasterella. Salmonella abony. and Escherichia coli.
Key words: Artemisia annua L.; essential oil; antimicrobial activity.
|Babazhanova M.A., Sayfudinov A.K.|
Kinetic study of the phosphoribulokinase activity of the multienzyme complex of the calvin cycle in extracts from cotton leaves
The results of kinetic studies of the phosphorybulokinase activity of the multienzyme complex of the Calvin cycle in extracts from cotton leaves of variety 108-F are presented. Revealed complex peculiar forms of the curves depending on the reaction rate on the duration of the reaction, the amount of protein, the concentration of ribose-5-phosphate, ribulose-5-phosphate and ATP. The results obtained indicate the manifestation of coordinated regulatory effects in the multi-enzyme complex. Due to these effects, ribose-5-phosphate increases the agent to the substrate and the activity of phosphorybulokinase, which acts second after the ribose phosphate isomerase in this metabolic chain, i.e. in the cycle of Calvin.
Key words: cotton; phosphorybulokinase; reaction; speed; kinetics; multienzyme complex; Calvin cycle.
|Fayziev F.A., Yatimov S.B., Usmonov N.K., Saidov A.I., Nazarov Kh.Y., Fayziev A.R.|
Silver-containing minerals of the deposits of the Takeli ore field (South-Western Karamazar)
The article provides information about silver sources in the deposits of the Takeli ore field. First of all, these are silver minerals represented by native silver, argentite, proustite, pyrargyrite and polybasite. The latter was discovered by us for the first time. In addition, silver is contained in sulfides and sulfosalts.
Key words: silver mineralization; native silver; argentite; galena; proustite; polybasite; pyrargyrite; tetrahedrite; chalcopyrite; sphalerite; pyrite; arsenopyrite.
|Petrov G.N., Kholmukhammadzoda S., Akhmedov Kh.М.|
Analysis of the modern practice of regulating a water flow by the large reservoirs of the Aral sea basin
In this article it is shown that often raised concerns are groundless that the initial filling of reservoirs may have a negative impact on the water availability of downstream countries.
Key words: reservoir; river flow; useful volume; dead volume; energetics; irrigation; transboundary rivers; flow regulation.
|Rashidov N.D., Gulov S.M.|
Grape leaves productivity dependent from heigh of the bush
In this paper the data on study of the productivity of the assimilation apparatus of Taphi pink grapes are ptesents. According to obtained results of studies, it was found that with an increase in the area of nutrition, the number of shoots per bush increases, but the number of leaves on the shoots in not changed. High-stem bushes with a height of 140 cm prevail in comparison with other of the experimental variants.
Key words: grapes; bush; stamb; formation; photosynthesis; productivity; leaf; area; number of leaves.
|Hasanzoda S.M., Sharipov K.O., Saidov Yo.U., Abdulatif A.|
Peculiarities of transmitral diastolic flow disorder in patients with rheumatoid arthritis in combination with ischemic heart disease
In this article analyses and are presents the results of studying of the formation features, the possible etiopathogenetic factors and the prognostic role of diastolic dysfunction of left ventricle and other determinants of structural and functional re-modeling of the left heart in patients with rheumatoid arthritis in combination with ischemic heart disease. The multifactorial genesis of diastolic dysfunction and structural and functional rearrangements of the left heart as a whole, which become active initiators of destabilization and progression of ischemic heart disease in patients with rheumatoid arthritis.
Key words: rheumatoid arthritis; ischemic heart disease; diastolic dysfunction; the left heart.