Доклады Академии наук Республики Таджикистан, том 57, №4, 2014 г.
|Article title and abstract||Pages|
On the distance between consecutive zeros of the first order derivative of the Hardy function
The lower bound of the gap length in the critical line, which includes the odd-order zero of the first derivative of Hardy function, is found by the method of optimization of exponential pairs.
Key words: функция Харди; экспоненциальная пара; дзета-функция Римана; критическая прямая; Hardy function; exponential pair; the Riemann zeta function; critical line.
Optimal cubature formulas for the classes functions determined by the modulus of continuity
We solve the optimization problem of finding the best cubature formulas for certain classes of functions determined by the modulus of continuity, depending on the distance of points in l
(1≤ p <∞)-norm.
Key words: кубатурная формула; погрешность; модуль непрерывности; cubature formula; error; the modulus of continuity.
|Mirzoev S.S., Fayziev M.G.|
Statement of classical problems for the nonclassical equation of the 4th order
In this work the classical boundary value problems for the nonclassical (composite) equation of the 4th order and investigate the nature of their solvability we considered.
Key words: уравнения неклассического (составного) типа; уравнение Эйлера-Пуассона-Дарбу (ЭПД); формула Пуассона; функция Грина; видоизменённая задача Коши; the equations of nonclassical (composite) type; equation of Euler-Poisson-Darboux (EPD); Poisson’s formula; Green’s function; Cauchy’s modified problem.
On optimal boundary control of forced oscillations of the displacements at one end of a string at the free second
In this paper we consider the problem of optimal boundary control processes described by equations of forced oscillations at one end of the string at the second free. For any period of time T >2 l , where l - length of the string found function u (0, t )= μ ( t ) transform the system variations from the initial state to the final and minimizes the integral boundary energy.
Key words: optimal boundary control; forced oscillations; integral boundary energy; оптимальное граничное управление; вынужденные колебания; интеграл граничной энергии.
|Usmanov Z.D., Dovudov G.M.|
On a set of tajik root anagrams
Thanks to special coding of roots, extracted from Tajik text collections, containing about 55million words, the sets of anagrams to Tajik roots are constructed. Statistical data on the number of different anagrams with a given number of elements are obtained. Some anagrams with the highest number of roots are presented for consideration.
Key words: таджикский язык; словоформа; корень; кодирование; анаграмма; статистика; Tajik language; word form; root; coding; anagram; statistics.
|Babadzhanov P.B., Kokhirova G.I., Obrubov Yu.V.|
Cometary nature of the potentially hazardous asteroid 2007CA19
The potentially hazardous asteroid 2007CA19 is empirically classed as the extinct or dormant Jupiter-family comet according to its Tisserand criterion’s value Tj =2.8. The investigation of the orbital evolution shows that the 2007CA19 is a quadruple crosser of the Earth’s orbit. If the 2007CA19 is really a former comet then at past it might form a meteoroid stream. At present this developed meteoroid stream should produce four meteor showers if the dispersion of the perihelion arguments of stream meteoroids covers the range in length of 360 deg. Using the 2007CA19 osculating orbits which intersect the Earth’s ones, theoretic radiants of the predicted showers were calculated. A search for predicted nighttime showers showed that the Northern and Southern η- Virginids are rather identified as these showers. Two daytime showers possibly associated with the 2007CA19 were revealed by us using the MOID IAU database. The relationships of the 2007CA19 with the meteoroid stream producing four active meteor showers confirms the above empirical classification and also points to its cometary origin.
Key words: орбита; эволюция; околоземной астероид; угасшая комета; метеороидный рой; метеорный поток; orbit; evolution; near-Earth asteroid; extinct comet; meteoroid stream; meteor shower.
Time and field dependences of the current in poly(ethylene terephthalate) at constant temperature
Time and field dependences of a current in poly(ethylene terephthalate) are considered at constant temperature. It is shown that features of time and field dependences correlate with the processes of formation of the deep localized states of the injected charge in nearby surface areas of the sample.
Key words: электрет; термоэлектронная эмиссия; инжектированный заряд; молекулярная подвижность; структурная ловушка; electret; thermionic emission; the injected charge; molecular mobility; a structural trap.
|Khamidov F.A., Badalov A., Mirsaidov U.M.|
Thermal decomposition of thorium (IV) and uranyl (VI) nitrates
In this work data on thermal decomposition of thorium (IV) and uranyl (VI) nitrates is presented. By means of tensimetry method it is found that thorium nitrate (IV) thermally decomposed at temperature range 430-470 K in one stage and uranyl (VI) nitrate at 430-750 К in two stages. Thermodynamic properties of thermal decomposition of individual compounds and were defined.
Key words: термическое разложение; нитраты тория (IV) и уранила (VI); тензиметрия; термодинамические характеристики; температурный интервал; thermal decomposition; thorium (IV) and uranyl (VI) nitrates; tensimetry; thermodynamic properties; temperature interval.
|Abdullaev Kh.M., Shaimov E.D., Tabarov F.S., Yuldashev I.|
Features of flow curves of lc-copolyesters and structural-mechanical parameters of extrudates received in different phase states of the melt
Соpolyesters on the basis of poly(ethylene terephthalate) and acetoxybenzoic acids above melt temperature are found out by two phase regions: low-temperature region, where in nematic to a phase are present high-melting crystallites, and high-temperature region, where it is formed homogeneous nematic melt. For heterophase melt anomaly of flow curves and the time instability of shear viscosity caused by development of processes of crystallisation and a disorientation of structural elements is characteristic. Viscosity of homogeneous melts does not depend on time and flowability diagrams liquid-crystal melts have a usual appearance for thermoplastics with an insignificant deviation from Newtonian flow regime. Extrudates received from homogeneous melt, have essentially higher values of molecular orientation and strength in comparison with extrudates formed of heterophase melt.
Key words: сополиэфир; вязкость; нематическая фаза; ЖК-расплав; экструдат; copolyester; viscosity; nematic phase; LC melt; extrudate.
|Degtev M.I., Yuminova A.A., Aminjanov A.A., Maksimov A.S.|
Organic-solvent-free extraction systems with phase separation based on antipyrine, sulfosalicylic acid, sodium sulphate and water for extraction of methal ions macroamounts
It is determined that the aqueous system delamination occurred in the case of pouring of 2 mol/L solutions of antipyrin (AP) and sulfosalicylic acid (SSA) in the molar ratio of 2 : 1. Volume of lower organic phase (OP) equal to 3.25 ml depends on the concentration of original components, appending salting-out agent and the medium acidity. The ratio of components AP : SSA : H
O into organic phase was determined. The optimal conditions for the macroamounts extraction of Fe (III), Ga (III), In (III), and Tl (III) were established. The extraction mechanism and the composition of extracted complexes were suggested.
Key words: антипирин; сульфосалициловая кислота; высаливатель; расслаивание; ионы железа (III); ионы галлия (III); ионы индия (III); ионы таллия (III); механизм экстракции; antipyrin; sulfosalicylic acid; salting-out agent; phase separation; iron ions (III); gallium ions (III); indium ions (III); thallium ions (III); extraction mechanism.
|Beknazarova Kh.A., Navruzshoev D.|
Biological-morphological features of
B. Fedtsch. in Pamir botanical garden
The number of species of the genus Ferula in the world and in the Republic of Tajikistan is reported. Native habitats and biological-morphological features of Ferula gigantea in introduction in Pamir Botanical Garden are characterized. According to our research, the species is monocarpic. The life cycle of plants is studied in cultivation.
Key words: биология; морфология; ферула; интродукция; рост; развитие; ареал; biology; morphology; Ferula; introduction; growth; development; distribution area.
|Safaralikhonov A.B., Aknazarov O.A.|
Diurnal and seasonal dynamics of transpiration intensity of horse bean leaves under influence of the UV-irradiation of seeds
In this article we brought up the experimental materials for diurnal and seasonal dynamics of transpiration intensity of horse bean leaves under influence of the replant UV- irradiation of seeds. It shows that the replant UV-irradiation of seeds relatively changes the diurnal and seasonal dynamics of transpiration intensity of horse bean leaves.
Key words: УФ-радиация; конские бобы; транспирация; UV-radiation; horse bean; transpiration.
|Rakhimova U.H., Nosirova M.P., Edgorova M.D., Mamadjanova G.S., Umarova Z.K.|
The symptoms and treatment of children with constitutional anomaly, who suffered perinatal encephalopathy
The results showed that children born in asphyxia manifestations minor cerebral dysfunction was noted perinatal encephalopathy, which was an important predisposing factor in the formation of the diathesis-abnormalities of the constitution, that is genetically determined the peculiarity of metabolism. Along with clinical manifestations diathesis, noted increased nervous anxiety, migraine, emotional lability, dysuric disorders, tik disorders. A comparative analysis of complex treatment with the appointment of two sedatives (children tenoten and Valerian root extract), noted that the drug tenoten child was more effective. Tenoten possesses anxiolytic effect, a calming effect, regulates the processes of excitation and inhibition, normalizes the function of the central nervous system, eliminates psycho-emotional stress.
Key words: аномалия конституции; перинатальная энцефалопатия; тенотен; constitutional anomaly; perinatal encephalopathy; tenotene.
|Sultonov Sh.R., Abdulloev M.F., Rakhmonov Sh.D., Aslamov B.N., Akhmedov R.Sh.|
The laparoscopic extraction methods of cecal appendage by acute appendicitis of children
On the basis of laparoscopic treatments of acute appendicitis and its complications of 85 children improved by method of extraction of cecal appendage in which 42 cases of extraction of cecal appendage is carried out on advanced method received the positive result in all these cases. The postoperative complications are not noted. The methods of improvement extraction of gross specimen after its laparoscopic removals is technically simple, rather effective and favourable.
Key words: лапароскопия; аппендицит; осложнения; дети; экстракция; laparoscopy; an appendicitis; complications; children; extraction.