Physics Commons^™

Sufficient Condition For The Possibility Of Completing The Pursuit, Nodirbek Umrzaqov

Scientific Bulletin. Physical and Mathematical Research

In this paper, the problem of chase is represented by a system of linear differential equations of motion dynamics. In this case, there is an integral limit to the control parameter of the evader, and a geometric limit to the control parameter of the pursuer. The pursuer is allowed to use the control that the fugitive has used so far to build his control. There are enough conditions for the game to end even if it starts from any starting point. An algorithm for constructing the control function of the pursuer is defined. It should also be noted that the …

Infinite Peirce Distribution In The Algebra Of Compact Operators And Description Of Its Local Au-Tomorphisms, Farhodjon N. Arzikulov, Rejabboy Qo’Shaqov

Scientific Bulletin. Physical and Mathematical Research

In the present paper the infinite Peirce decomposition of the algebra 𝐾(𝐻) of com-pact operators on an infinite dimensional separable Gilbert space 𝐻 is constructed, using the norm of the algebra 𝐾(𝐻) and a maximal family of mutually or-thogonal minimal projections, i.e., self-adjoint,idempotent elements. The infinite Peirce decompo-sition on the norm of a 𝐶∗-algebra is also con-structed in 2012 by the first author. But, it turns, the condition, applied then, is not sufficient for the infi-nite Peirce decomposition on the norm constructed in 2012 to be an algebra. Therefore, in the present paper, the infinite Peirce decomposition on the norm …

Effect Of Excess Tellurium And Lead On Defor-Mation - Characteristics Of Polycrystalline Pbte Films, Yu.Yu. Vaitkus, Otajonov Salimjon

Scientific Bulletin. Physical and Mathematical Research

In this work, we studied the ef-fect of excess tellurium and lead on the defor-mation characteristics of polycrystalline PbTe films obtained on different substrates. It was found that the resistance of the films first increases and reach-es a maximum, and with a further increase in the level of deformation, it decreases and the sign of the tensile resistance begins to change, which are associated with the presence of internal stresses in the films. It was also shown that with an increase in the amount of lead in the composition of the PbTe film, the electrical conductivity increases in com-parison with …

Structure And Electrophysical Properties Of A Solid Solution (Gaas1-Δbiδ)1-X-Y(Ge2)X(Znse)Y, S.Z. Zainabidinov, I.N. Karimov, Hotamjon Mansurov, Akramjon Boboev, Dilkhayotjon Pulatjon Ugli Abdurakhimov

Scientific Bulletin. Physical and Mathematical Research

This paper shows the possibility of growing a single-crystal solid solution of substitution (GaAs1-δBiδ)1-x-y(Ge2)x(ZnSe)y on GaAs substrates by liquid-phase epitaxy from a bismuthcontaining solution-melt. The grown films had a ptype of conductivity with a current carrier concentration of 1,86·1017 сm-3, a mobility of р = 300 cm2/V·s, and a resistivity of 0,13 Ohms·cm. Structural studies have shown that the epitaxial films have a sphalerite structure of the ZnS type and are monocrystalline with an orientation of (100). The crystal lattice parameter of the film was af = 0,56697 nm. Studies of current-voltage characteris-tics of n-GaAs – p-(GaAs1-δBiδ)1-x-y(Ge2)x(ZnSe)y heterostructures at different …

Simulation Of Self-Heating Effect In Mosfet Based On 2d Mos2, Atabek E. Atamuratov, Xushnudbek Sh. Saparov, A Yusupov, Frank Schwierz

Scientific Bulletin. Physical and Mathematical Research

One of the main trends of today's electronics is the decreasing the sizes of MOSFET up to nanometer scale. In this connection there are two main views to the perspective of scaling. According to one of them limit of scaling is reached at sizes 10 nm order, however according to second view, still there are opportunity to decrease transistor to more lower sizes. In accordance with second approach it is suggested to continue the size scaling by modification the transistor structure or by using the new materials, particularly one or two dimensional materials. One of such suggestions is the designing …

Method Of Characteristics For Solving The Problem Of Gas Outflow From An Elementary Sec-Tion Of A Gas Pipeline, Madaminjon K. Mahkamov, S.S. Akhmadjonov, I.K. Khujaev

Scientific Bulletin. Physical and Mathematical Research

Numerous problems based on equations of hyperbolic type are solved by the method of characteristics when boundary conditions of the first, second and third kinds are set on the boundary. These include, in particular, the problems of pipeline transportation of various media. The quasi-one-dimensional equations of conservation of mass and momentum are linearized and separate equations are drawn up for a specific indicator (flow rate, gas pressure) of the process. This approach is associated with the tradition of forming boundary conditions and solving problems only with respect to a specific indicator, in particu-lar, with respect to pressure, velocity, and flow …

Electrophysical Properties Of Supercapacitor On The Basis Of New Gel Polymer Electrolyte, J.A. Shodmanov, Azamat Boymirzaev

Scientific Bulletin. Physical and Mathematical Research

The results showed a slight increase in internal resistance under the influence of bending and confirmed that the equivalent circuit model of electrons did not change under bending conditions as indicated in graphically illustrated the results by cyclic voltamperometry (TsV) at a scanning speed of 10 mV / s under the above bending angles of the SK prepared on the basis of PG 10 GPE. From ex-periments we found that the shapes are almost rec-tangular, with no redox peaks observed. We can see that the area of the TsV curves changes slightly as the bending angle increases, but this does …

Influence Of A Strong Magnetic Field On Fermi Energy Oscillations In Two-Dimensional Semiconductor Materials, Gafur Gulyamov, Ulugbek Inayatillyevich Erkaboev, Rustam Gulomzhonovich Rakhimov, Nozimjon Sayidov Sayidov, Jasurbek Mirzaev

Scientific Bulletin. Physical and Mathematical Research

This article discusses the effect of a quantizing magnetic field and temperature on Fermi energy oscillations in nanoscale semiconductor materials. A generalized mathematical expression is obtained for calculating the dependence of the Fermi energy oscillations on the magnetic field, temperature, and thickness of the quantum well. It is shown that the Fermi energy in nanoscale semiconductor materials under a quantizing magnetic field is quantized. The proposed theory explains the experimental results in two-dimensional semiconductor structures with a parabolic dispersion law.

Determination Of The Specific Thermo Emf Of Granulated Silicon Doped With Alkaline Metals., B.M. Abdurakhmanov, Zarnigor Sohibova, M.M. Adilov

Scientific Bulletin. Physical and Mathematical Research

The value of the specific thermo EMF is one of the most important thermoelectric parameters of a material and in practice is estimat-ed mainly by two well-known methods - integral and differential. To measure the thermo EMF of granular silicon, we used a differential method. In this work, the thermoelectric properties of granular silicon containing alkali metal atoms have been studied, the presence of which, for example, in single-crystal structures makes it possible to improve the characteristics of a number of devices, and in polycrystalline ones, the effect of grain boundaries on the electrical properties, in particular, to reduce the …

The State Of Solar Energy In Uzbekistan In The Framework Of The Devel-Opment Of Renewable Energy Sources, E.Z. Imamov, Ramizulla Abdullaevich Muminov, Temur Asfandiyarovich Djalalov, I.Sh. Abdullaeva

Scientific Bulletin. Physical and Mathematical Research

The paper analyzes the possibilities of renewable energy sources to become the main sources of ener-gy that can in the future replace traditional technologies for the production of thermal and electrical energy based on the use of fossil fuels and nuclear energy.

Technological approaches are considered that make it possible to significantly increase the efficiency of solar energy, and it is also shown that such a possibility can be realized by using weakly crystalline and cheap modifications of silicon, which have previously passed the corresponding nanotechnological effect.

Properties And Applications Of Metal-Oxide Thin Films In Converters Of En-Ergy (Review), Shakhriyor Kh. Yulchiev, Akramjon Boboev, Xushruybek Mahmudov

Scientific Bulletin. Physical and Mathematical Research

Metal-oxide semiconductors (SnO2, ZnO, TiO2, etc.) have a wide band gap (~3 eV) and are trans-parent in the visible range of the optical spectrum. Therefore, transparent semiconductor devices (diodes, transistors, integrated circuits, etc.) can be made based on them. There are two peaks in the emission spectrum of the LED. One of the peaks (3.3 eV), apparently, is as-sociated with exciton recombination, and the other peak is associated with recombination through a deep impuri-ty level. The emission spectrum of the LED was ob-served at a direct current of 40 mA. The electrolumines-cence spectrum obtained on the heterostructure at room temperature …

Development And Implementation Of A Photovoltaic Power Plant With A Capacity Of 3-6 Kw With “Smart Greed” Elements In The Conditions Of The Fergana Valley, Райимжон Алиев, Жамшидбек Каххоров, Авазбек Мирзаалимов, Наврузбек Мирзаалимов, Бобур Рашидов

Scientific Bulletin. Physical and Mathematical Research

Today, solar cells are manufactured at the industrial level mainly from polycrystalline and monocrystalline silicon. Solar elements made of silicon make up more than 90% of the solar elements that are produced worldwide. Depending on the seasons of the year in the Ferghana Valley, the movement of the Sun, geographical location, air humidity, temperature changes, the intensity of light falling on the surface of solar panels and other parameters, the characteristic (I-V) of solar panels was studied. The installation of solar panels installed at Andijan State University consists of the installation, commissioning and analysis of the results obtained on sunny, …

A Cauchy-Goursat Problem For A Second Kind Degenerated Equation Of Hyperbolic Type, Doniyor Usmonov

Scientific Bulletin. Physical and Mathematical Research

In the work a Cauchy-Goursta problem has been formulated and investigated for a second kind degenerated equation of hyperbolic type. During the investigation, it was used properties of Gauss’s hyper geometric function and symbol of Pochhammer, the considered problem equivalently reduced to an integral equation with respect to trace of unknown function. Properties of Riemann-Liuvill integral-differential and generalized integral-differential operators have found solution of the taken integral equation. To find solution of the problem it was used general solution of the equation. A class of generalized solutions was introduced for the correctness of the problem. It was found necessary conditions …

Evolution Of Quantum Systems Consisting Of Mul-Tiple Various Particles Interacting With General-Ized Yukasha Potential, N.N. Bogolyubov, Rasulova Mukhayo, U.O. Avazov

Scientific Bulletin. Physical and Mathematical Research

In this paper, multi-variety densely packed par-ticle dynamic systems with the ability to interact with the shielded Yukawa potential were studied. Also, in order to study more widely the dynamics of systems containing particles interacting via shielded potential, the theoretical foundations of the dynam-ics of systems consisting of an arbitrary number of bounded - sorted multi-particles are analyzed. The dynamics of an arbitrary number of interacting par-ticle systems on a screening potential was studied using the Bogolyubov-Born-Green-Kirkwood-Yvon (BBGKY) chain of quantum kinetic equations. The BBGKY chain of quantum kinetic equations has solutions for the case that characterizes the evo-lution of …

Measurement Of Geometric Fractals On The Basis Of Hausdorf-Bezikovich And Minkovsky-Buligan Measurements, Anorova Amanbaevna Shaxzoda, Jabborov Sindorovich Jamoliddin, Meliyev Fattoevich Farxod

Scientific Bulletin. Physical and Mathematical Research

This article is devoted to the study of the future position of fractal measurements. Different methods of computer modeling of a wide range of classes of fractal geometric objects are described in detail, as well as the main methods of mathematical analysis of fractal size of virtual and real fractals are described. The article explains the differences between the concept of fractals, their properties, B. Mandelbrot's tariff, Hausdorf-Bezikovich scale, Minkowski-Buligan scale, topological measurement, the concept of fractal measurement and measurement in Euclidean geometry. This article provides basic information about fractals. A detailed description of the various methods of computer modeling …

Аn Optical Study Of Strain Relaxation And Interdiffusion In Znse/Zncdse Quantum Wells Modified By Γ-Irradiation, Muratbay B. Sharibaev, Kanatbay A. Ismailov, Ibrohim N. Karimov, Murodjon Z. Nosirov

Scientific Bulletin. Physical and Mathematical Research

If we turn to the literature data, it is known that the degradation of CdZnTe / ZnTe and CdZnSe /ZnSe quantum wells and usually includes two types of processes: (i) fast (as called dynamic, by analogy with the degradation of heterostructures based on A3B5 materials) - germination and propagation of extended defects from a GaAs substrate. This process in CdZnSe / ZnSe is slowed down by various technological methods (treatment of a substrate in sulfur; reduction of a damaged layer in a GaAs substrate; deposition of a GaAs epitaxial buffer layer; use of the concept of compensation of bipolar stresses; …

Obtaining, Structure And Electrophysical Properties Of The Solid Solution (Gaas1-Δbiδ)1-X-Y(Ge2)X(Znse)Y, Hotamjon Mansurov, Akramjon Boboev, Johongir Usmonov, Xushruybek Mahmudov, Dilkhayotjon Pulatjon Ugli Abdurakhimov

Scientific Bulletin. Physical and Mathematical Research

This work shows the possibility of growing a single-crystal substitutional solid solution (GaAs_1-δBi_δ)₀.₄₆(Ge₂)_0.31(ZnSe)_0.23on GaP substrates by liquid phase epitaxy from a bismuth-containing melt solution. was shown that tetrahedral bonds in the (GaAs_1-δBi_δ)₀.₄₆(Ge₂)_0.31(ZnSe)_0.23 layers are enriched with arsenide gallium molecules, and some GaAs_1-δBi_δ molecules are replaced by Ge₂ paired atoms and ZnSe molecule compounds. Experimental results showed that in the epitaxial film, the molar content of GaAs …

Hyperfine Interactions In Copper Lattice Sites Of Antiferromagnetic Compounds, Sirojiddin Z. Zainabidinov, Alla V. Marchenko, Pavel P. Seregin, Kudrat U. Bobokhuzhaev

Scientific Bulletin. Physical and Mathematical Research

Emission ⁶¹Cu(⁶¹Ni) Mössbauer spectra of dielectric metal-oxide compounds of divalent copper with molecular formulas correspond to the quadrupole and Zeeman interactions of the ⁶¹Ni nuclei with local fields at the copper lattice sites, whereas the spectra of superconducting metal-oxide complexes correspond to the interaction of the quadrupole moment of the ⁶¹Ni nuclei with the tensor of the electric field gradient.

Optimization Of The Automatic Operation Of The Plastic Crushing Machine, Yokubjon E. Kurbonov, Madaminjon K. Mahkamov, Nodirbek Sh. Kimsanboyev

Scientific Bulletin. Physical and Mathematical Research

The main costs in the production of plastic products that affect the cost of the product is the cost of materials. It accounts from 70% to 77% of all expenses. For this reason, the processing of plastic products and their use as secondary raw materials reduces the cost of production and leads to increased economic efficiency.

In order to obtain high-quality secondary raw materials by crushing plastic products, it is necessary to divide them into types before crushing. For classification and identification of plastic products, a fluorescent material is used to determine the composition and concentration of plastic. The result …

Study Of Diffusion, Solubility And Electrophysical Properties Of Scandium, Praseodymium And Europium In Silicon, Sirojiddin Z. Zainabidinov, Dilshad E. Nazyrov, Valentina P. Usacheva

Scientific Bulletin. Physical and Mathematical Research

The purpose of the present work was a comprehensive study of the diffusion, solubility and electrophysical properties of scandium (Sc), praseodymium (Pr) and europium (Eu) impurities in silicon. On the surface of the KEP-15 a layer of radioactive isotopes was sprayed: ⁴⁶Sc, ¹⁴³Pr₂O₃, or ¹⁵²Eu₂O₃. The duration of diffusion annealing varied depending on the diffusion temperature of 5 to 72 hours. Autoradiography, measurements of conductivity and Hall's effect, an isothermal relaxation of capacity and current, a research of diffusion, solubility and electrophysical properties of Sc, Pr and Eu in …

Development Of A Mobile Device For Drying Paddy, Botirali R. Bekkulov

Scientific Bulletin. Physical and Mathematical Research

The author of the article describes the results of scientific research aimed at creating a patented new design of a mobile drum device and ensuring an increase in the amount of paddy due to high-quality drying by substantiating its parameters. Firstly, an analysis of scientific research and patent information materials of existing devices for drying sludge working in a convective way, the existing advantages and the main disadvantages of existing devices are determined. Based on the analysis, the requirements of the newly developed device for drying the paddy are formed, theoretical research is carried out, the purpose of which was …

Growth And Investigation Of The (Gaas)1–X–У(Gе2)X(Znse)Y Semiconductor Alloy, Amin S. Saidov, Sirojiddin Z. Zainabidinov, Shakhriyor Kh. Yulchiev, Akramjon Y. Boboev

Scientific Bulletin. Physical and Mathematical Research

In this article, the experimental and theoretical studies on technology for producing the single-crystal semiconductor alloy (GaAs)_1–x–у(Gе₂)_x(ZnSe)y on GaAs substrates with the crystallographic orientation (100) by the liquid-phase epitaxy method is presented. The optimal process conditions of structurally perfect epitaxial layers were determined (cooling rate is 1 oC/min, temperature is 730–640°С, and growth rate ϑ = 0.15 μm/min). The grown epitaxial films possessed thickness values of 10 μm and р-type conductivity with resistivities of 0.1 Ω cm and the concentration of carriers of 5.1·10¹⁷ cm^-3.

Synergetic Simulation Of Nanostructure Growth Processes In The Volume Of Mesophase Of Silicon And Germanium, Sirojiddin Z. Zainabidinov, Bakhodirjon Askarov, Shukhratjon K. Akbarov

Scientific Bulletin. Physical and Mathematical Research

A new approach is proposed for studying the processes of nanoparticle growth under nonequilibrium conditions associated with vibronic effects. The adiabatic potential for studying atomic rearrangements of a local group of atoms is constructed. The nanoparticle growth process was studied by the method of synergetic modeling, taking into account the anharmonic terms in the adiabatic potential. Based on the methods of catastrophe theory, the conditions for the instability in a local group of atoms are found. It is shown that the number of bound atoms in a local group affects the stability of the local group of atoms. An analytical …

Features Of The Physical Properties Of The Modified Surface Of The P-Cdte – Znse Film Heterostructure With Deep Impurity Levels, Yuozas Y. Vaytkus, Nodir E. Alimov, Salim M. Otajonov

Scientific Bulletin. Physical and Mathematical Research

This article analyzes the spectrum of the photocurrent in a layered film heterostructure CdTe-ZnSe with deep primesnymi levels. The experimental results demonstrated that the heterostructure CdTe-ZnSe observed a new effect in the measurement of the photoconductivity spectra, depending on the direction of the applied electric field, and the applied field stimulates the emergence of photo-emf. The spectrum of the photocurrent in a layered CdTe- ZnSe heterostructure film with deep impurity levels are considered in the article. It follows from the experimental results that a new effect is observed in the CdTe-ZnSe heterostructure when measuring the photoconductivity spectra depending on the …

Definition Of Extended Structural Defects In Epitaxial Films Of Znteg‘Gaas Grown By Mbe, Muratbay B. Sharibaev, Kanatbay A. Ismailov, Ibrohim N. Karimov, Murodjon Z. Nosirov

Scientific Bulletin. Physical and Mathematical Research

The last three decades of the development of solid state physics are characterized by the fact that the main objects of research are increasingly not massive crystals, but thin films, multilayer thin-film systems, conducting filaments and crystallites of small size. Epitaxial films are grown on a substrate of a single crystal of the same or another material. In the first case, the epitaxial layer with the correct technology becomes a natural extension of the substrate. Epitaxial film can be doped with various impurities. To introduce an alloying admixture into the epitaxial film, three methods are used. According to the first …

Spectral Characteristics Of The Absorption Coefficient And Energy Position Of Defects, Sirojiddin Z. Zaynobidinov, Rustamjon G. Ikramov, Mashhurahon A. Nuriddinova, Khurshid A. Muminov

Scientific Bulletin. Physical and Mathematical Research

In this paper, a theoretical method to study the spectral characteristics of the absorption coefficient, namely the area of ​​defective absorption of amorphous hydrogenated silicon according to the Davis-Mott approximation from the Kubo-Greenwood formula. It is shown that using the experimental spectral characteristic of the defect absorption coefficient, one can determine the energy position of defects in the mobility gap. Optical transitions of electrons, in which electronic states participate in defects, indicate that there are three types of optical transitions of electrons: between defects, between defects and tails of allowed zones, and also between defects and allowed zones. It was …

Sub-Barrier And Above-Barrier Electron Transport Through Multilayer Semiconductors, Vohob R. Rasulov, Rustam Y. Rasulov, Ikbol M. Eshboltaev, Ravshan R. Sultonov

Scientific Bulletin. Physical and Mathematical Research

In the article the transparency coefficients of the semiconductor structure, consisting of alternating asymmetric potential barriers and wells, where the Bastard condition is taken into account, are calculated. It is shown that in the structure there should be an oscillation of the transmission coefficient of electrons depending on their energy, which is due to the interference of the de Broglie waves reaching the barrier and reflected from the potential barrier. The electronic states of a multilayer semiconductor structure consisting of alternating potential wells and barriers are analyzed. It has been shown that both in the above-barrier and in the barrier …

Scientific Foundation Of The Rate Of Falling Of Raw Materials On Walnut Breakage Device, Otabek A. Mirzaev, Xolhuzha A. Sobirov, Nusratillo R. Barakaev

Scientific Bulletin. Physical and Mathematical Research

Today, there are many types of fruits that are separated the kernel from the shell: walnuts, almonds, filberts, chestnuts, pistachios and cashews. Nuts have a high calorific value and a rich nutrient composition. The most critical and delicate operation is shell cracking to extract the fragile whole kernel from the shell. Studies on nut rupturing are particularly focused on the following three aspects: the physical characteristics of nuts, the mechanical properties of nut rupturing, and nut rupturing equipment. Determining the velocity of the nut entered into the apparatus will allow the machine to operate normally, but will also increase its …

Studies Of Tribotechnical Properties Of Composite Polymeric Materials Of Machine Designation, Tojiboy O. Almataev, Nozimbek T. Almataev

Scientific Bulletin. Physical and Mathematical Research

In the given work are experimentally investigated tribotechnical properties as intensity of wear process and factor of a friction composite epoxy the polymeric materials processed by ultrasound. Results of influence of a kind and the maintenance loading on tribotechnical properties composite epoxy polymeric materials depending on modes of ultrasonic processing are received. Correlation dependence of intensity of wear process and factor of a friction composite epoxy coverings from modes of ultrasonic processing is established. It is shown in the work that with an increase in the duration of ultrasonic exposure, the wear rate and the friction coefficient of the coatings …

Structure And Electro Physical Properties Of Solid Solution (Si2)1-X(Cds)X (0 £ X £ 0.01), Xurshidjon M. Madaminov

Scientific Bulletin. Physical and Mathematical Research

This paper shows the possibility of obtaining a single-crystal solid solution for the substitution of p-Si-n-(Si2)1-x (CdS)x (0 £ x £ 0.01) on silicon substrates with a diameter of 20 mm and thickness » 400, with a crystallographic orientation (111) n-types of conductivity with a specific resistance of 1 Ω cm, by the method of liquid phase epitaxy from Sn – Si – CdS solution – melt in a hydrogen atmosphere purified by palladium. Perfect epitaxial layers with mirror surfaces and with the best parameters are grown under the following technological conditions: temperatures start crystallization –1150 ОС, speed of forced …