Доклады Академии наук Республики Таджикистан, том 60, №5-6, 2017 г.
|Article title and abstract||Pages|
On the application of the asymptotic method to differential equations with deviating argument
The article deals with considering a method of separating a family of asymptotic solutions of differential equation with deviating argument, when solutions themselves are not built and describe their differential equation without deviating argument.
Key words: метод сведения; условия Липшица; метод последовательных приближений; интегральное уравнение; равномерная сходимость; information method; Lipschits conditions; method of successive approximations; the integral equation; uniform convergence.
On boundary control by elastic forces at both endpoints of the process of forced string vibrations for the minimum time period
The necessary and sufficient conditions for existence of unique boundary controls by elastic forces that ensure the transition of the oscillatory process described by the forced string oscillation equation from an arbitrary initial state to any predefined final state, are obtained. Explicit analytical formulas for calculating these boundary controls are also given.
Key words: граничное управление; уравнение вынужденных колебаний струны; упругая сила; критический момент времени; телеграфное уравнение; смешанная задача; boundary control; equation of forced oscillations of a string; elastic force; critical moment of time; telegraph equation; mixed problem.
|Rajabova L.N., Shukurova G.N.|
Cauchy-type problem for symmetric integral equations of type Volterra with singularity and a logarithmic singularity
In the article the solutions containing arbitrary constants of symmetric integral equation of Volterra type with a singular and logarithmic singularity, when the roots of the characteristic equation are equal or complex-valued are obtained. To determine the arbitrary constants the Cauchy problem is resolved.
Key words: симметричные уравнения; интегральные уравнения; сингулярная особенность; логарифмическая особенность; symmetric equations; integral equations; a singular feature; a logarithmic singularity.
|Shakirov I.A., Khasanov Yu.Kh.|
About of the allegations used to evaluate the Lebesgue constant of classical Fourier operator
The paper presents definitions of some classes of functions, that are used in the study of the fundamental properties of the Lagrange operators and obtaining of uniform lower and upper estimates of the Lebesgue constants of the classical Fourier operator.
Key words: оператор Лагранжа; норма оператора Фурье; константа Лебега; малая монотонная вариация; оценка константы Лебега; Lagrange operator; norm of Fourier operator; Lebesgue constant; small monotonous variation; estimation of Lebesgue constant.
Evaluation of bigramm use efficiency for a text identification
Efficiency of N.V.Smirnov's uniformity criterion and his modifier for identification of the author of a text by means of letter bigram frequencies are investigated.
Key words: таджикский язык; биграмма; частотность; статистика; эффективность; Tajik language; bigram; frequency; statistics; efficiency.
|Yusupov I.Kh., Umarov N.N., Marupov R.|
Molecular-dynamical and physical-mechanical characteristics of burdock medicine
The influence of ground the area grown on physical mechanical characteristics medicin plant of burdock have been investigated. It is shown that the medicinal strengh of the leaves of the plant depending on the presence of “defective” porous parts inside of which on intensive molecular motion takes place. Increasing of background radiation level leads to the reduction of mechanical toughness of the leaves activation energy and entropy. Comparison of the EPR-spectrum parametres reflecting marked labels mobility with the mechanical parametres of medicin plants afforded to establish their correlation.
Key words: прочность; энергия активации; спиновая метка; молекулярная динамика; репейник (Arctium tomentosum Mill.); strength; activation energy; spin label; molecular dynamics; burdock (Arctium tomentosum Mill.).
|Abdullaev S.F., Maslov V.A., Nazarov B.I., Karieva R.A., Djuraev A.M.|
Variants of greenhouse gas content in the atmosphere by AERONET data
The article presents the results of analysis of statistical regularities (mean monthly, average seasonal and diurnal variations) of the changes in the total ozone, nitrogen oxide and water vapor in the atmosphere, which were obtained during measurements at the AERONET station. It is shown that the dynamics of the investigated greenhouse gases strongly depends on the conditions of their generation and runoff, including from meteorological and anthropogenic factors.
Key words: АЭРОНЕТ; водяной пар; окись азота; озон; пылевая мгла; AERONET; water vapor; nitric oxide; ozone; dust haze.
|Nazarov F.A., Kurbonov A.S., Juraev J.D., Davlatov D.O., Nazarov Sh.B., Mirsaidov U.M.|
Sintering method of processing of boron-containing ore concentrate of Tajikistan in the presence of caustic sodium
The results of studies of the decomposition of the borosilicate ore concentrate of the Tajikistan Ak-Arkhar deposition by the sintering method are presented. The optimal decomposition conditions for the borosilicate ore concentrate by joint sintering with sodium hydroxide were determined.
Key words: концентрат; боросиликатная руда; переработка; спекание; разложение; извлечение; borosilicate ore concentrate; processing; sintering; decomposition; extraction.
|Khojiev S.K., Pulatov M.S., Muminov S.V., Bakhronov S.M., Ahmedov M.Z., Mirsaidov I.U.|
Physico-chemical basis of uranium ore processing by sulfuric acid decomposition
In the article the physico-chemical basis of uranium ores processing of the “Central Tajikistan” deposit are presents. A principal technological scheme for uranium concentrate production is proposed.
Key words: переработка; урановая руда; концентрат; десорбат; processing; uranium ore; concentrate; desorbate.
|Khalikov D.Kh., Bobodjonova G.N., Gorshkova R.M., Makhkamov H.K.|
An influence of acidity the solution and background electrolyte for yield and uranides from decomposition products the protopectin sunflower basket in solution flow
Interconnection of dividing the yields and monosaccharide composition the protopectin (PP) of sunflower basket (SB)- microgel (MG)pectin compounds (PC) and oligosaccharides(OS) regarding speed of stream the hydrolyzing solution from 3 to 6 mL/min in direct-flow extraction column at the condition of dynamic mode (DM) was studied. There is illustrated that by increasing of speed of stream occurs well-proportionated growth the contents of all components the reaction of decomposition reaction PP-MG, SB and OS. The contents of main components MG and PC are very close interse, but total content these products depending on flow rater un sup to 20-30 percent’s, which it is considerably more than that yields of pectin polysaccharides obtaining by the other conditions of reaction, by statistic conditions(SC). The management of flow rate promotes direct decomposition reaction of PP to predominantly direction of obtaining the MG or PC with high containing remainders the galacturonic acid.
Key words: протопектин; микрогель; пектиновые вещества; корзинка подсолнечника; рН; динамический режим; галактуроновая кислота; поток раствора; protopectin; microgel; pectin compounds; sunflower baskets; flow rate; рН; dynamic mode; galacturonic acid.
|Sharifov A., Ulukhanov Al.A., AAkramov A., Subhonov D.K., Shodiev G.G.|
Plant material to produce an effective organic modifier binders
In this article the results of the extraction of raw materials from the plant cane, cotton stalks, plane trees, poplar and mulberry with water and weak solutions of acids and alkalis, and proved the effectiveness of the extracts as an organic modifier properties plaster are present.
Key words: сырьё; экстрактивные вещества; растворитель органический; модификатор; вяжущие вещества; строительный гипс; время схватывания; прочность; raw materials; extractives; organic solvent; modifier; binders; gypsum; setting time; strength.
|Bohirova M.K., Abdullaev Kh.A., Giyasidinov B.B., Ergashev A.|
About post-defoliation effects on cotton plants
In this article the results of the post-defoliation effects on the cotton plants are present. During of the budding and flowering phases in the cotton plants of the leaves completely were removed. After 95-105 days growing the developing of new leaves is observed. The quantitative parameters of cotton plants leaves were equal to control plants. This process is a bright expression of reparative regeneration in higher plants.
Key words: тонковолокнистый хлопчатник; дефолиация; последействие; регенерация; long stable cotton; defoliation; regeneration after operation.
|Okhunjonov A.Kh., Yngiboev D., Felaliev A.S.|
Drought resistance of clonal rootstocks of apricot in condition of Northen Tajikistan
The clonal rootstocks of apricot in the branch of the Institute of horticulture and vegetable growing in B. Gafurov district of Sogd region allowed to assess the dryness of this rootstocks are study. In has been established that clonal rootstocks Mirobolan 29 C and Marianna 2624 possess a more adequate degree of relative drought resistance. This makes it possible to use this rootstocks to create intensive gardens of apricot in the northern zone of Tajikistan.
Key words: абрикос; клоновый подвой; засухоустойчивость; оводнённость; дефицит воды; водоудерживающая способность; apricot; clonal rootstock; drought tolerance; water content of leaves; water deficit; water holding ability.