Physics

The aim of the research work. Comprehensive study modification mechanisms and features forming nano-dimensional structures in the surface layers PdBa, CoSi2 and GaAs at low energy ion bombardment, followed by heat and laser treatment.
Scientific novelty of the research work. A structural model of the surface of Pd-Ba activated in high vacuum and in an oxygen atmosphere was proposed and a technique for uniformly activating the surface of Pd-Ba alloys of a cylindrical shape by laser ablation and implantation of Ba’ ions was developed;
It was shown that the shape and size of the nanocrystallinc phases formed on the surface of Pd and Pd-Ba at irradiation densities D < 1015 cm" depends mainly on the surface microrelief, and does not depend on D > 5 • 1015 cm’2 at high doses; The most likely mechanism for the formation of areas with a crystalline structure under the effect of implantation of large doses of ions is the heating of the target in the region of the thermal peak, leading to melting of the material;
homogeneous regularly located nanoscalc phases and epitaxial nanofilms of Si and CoSiO on the surface of CoSii/Si (111) were obtained by the ion bombardment method (Ar+ and O’) in combination with annealing, and also the dependences of nanocrystallinc phase dimensions on energy and ion dose were determined;
mechanisms for the formation of one-component nanoscalc structures on the surface of materials of various types (metal alloy Pd2Ba, semiconductors CoSi2 and GaAs) and the type of chemical bond (intermetallic, covalent and ionic-covalent) in the bombardment with Ar+ ions;
Optimal conditions for ion bombardment and subsequent annealing of the Si-CoSi2-Si, CoSiO-CoSi2-Si, Ga-GaAs-Gc, GaAlAs-GaAs multilayer structures were determined and their energy band diagrams were constructed.

The aim of research work is creation an injection photodetector with internal amplification based on p-CdTe films with a columnar grain structure and an investigation of electronic processes in such a photodetector.
Scientific novelty of research work:
the technology of obtaining high-resistance strongly compensated CdTe films with optimal output parameters by the method of gas-transport reaction in the flow of hydrogen has been developed;
it is ascertained that ultrasonic irradiation (UI) does not practically affect the regularities of the current flow both in the forward and reverse directions. It is shown that after the UI the forward current increases by about 25-30%, and the reverse current decreases by 6-9%, the rectification factor (K.) increases by 1.4 times;
the wide-band (X = 400-H000 nm) photodetector with internal amplification based on р-CdTe films with a columnar grain structure was created and investigated. Such photodetector without interference not only records light signals in the wavelength region X = 450^-750 nm, but also amplifies them.

Subject of research: carbon acids: one, two and polybasic aminoacids, aprotic acids (Lewis acids), amines, aqua, mixed aqueous-nonaqueous, nonaqueous-nonaqueous and nonaqueous solvents. Samples of objects in production.
Purpose of work: theoritical justification of the choice of the solvents for titrimetrical determination of one, two and polybasic carbon and aprotic acids, study the influence of nonaqueous solvents to the acids that have various chemical properties and differ by their strength and to the substances that express acidity property.
Methods of research: potentiometric methods, conductometric method, polarography, spectrophotometry, methods of the mathematic statistics.
The results obtained and their novelty: acidity constants of carbon, aprotic and aminoacids in aqueous, aqueous-nonaqueous, nonaqueous-nonaqueous and aqueous solutions have been evaluated, choice of the solvents for titrimetrical analysis of the acids was theoritecally justified, elaboration methodics of analysis.
Practical value: methods and methodics of the analysis for these components (individual and in mixtures) were developed. Accuracy, correctness and other metrological characteristics of the developed methodics are high. The developed methodics have been applied for the analysis of environmental objects.
Degree of embed and economic effectivity: The results obtained are introduced in the Samarkand Regional SEC, Samarkand GPGP "Suvoqava, Khorezm region. Committee for Nature Protection, as well as in the educational process in the departments of SamSU, UrSU and Sartepa college of tourism and service industries. The developed methodics would be introduced in practics in enterprises of chemical and food industry, in medical institutions and in agriculture.
Field of application: analytical chemistry, ecoanalytical monitoring, environmental protection, analysis of food products.

Subjects of research: solar heat and energy equipments, exactly, radiation characteristics of solar receivers and their influence to efficiency of equipments
Purpose of work: to develop methods and models intended to define efficiency of using selective surfaces in solar low and high temperature equipments and working out recommendations by their applications.
Methods of the research: There are used fundamentals of photometry, geometrical optics and theoretical bases of heat engineering, universally recognized methods of numerical solution of equation of thermal conductivity and methods of data handling.
The results obtained and their novelty: determination methodology of integrated radiation characteristics by equilibrium temperature which is notable with convection heat losses' new circuit of calculation; numerical model of "hot box" which is notable with convection heat losses from side surfaces and determination ability influence of receiving surfaces' selectivity to efficiency; determination methodology of optimal parameters (concentration, conversion temperature) of solar heat-and-power engineering equipments with selective receiver of radiation; determined: maximal efficiency of solar heat-and-power engineering equipments
Practical value: determination methodology of integrated radiation characteristics and its experimental refining can be used to determine radiation characteristics of different materials; developed thermal models of solar low temperature equipments and their numerical and software implementation can be used in degree validation of solar receiver's selectivity; results of system optimization receiver - thermodynamic reformer can be used to determine optimal parameters of receiver's selectivity, concentration of solar radiation and temperature transformation
Degree of embed and economic effectivity: results of the work allowed to base requirements to selectivity of solar radiation detectors and consequently to bring down costs to manufacturing them.
Field of application: low and high solar temperature equipments

Subjects of the inquiry: 103 patients with rheumatoid arthritis, 20 healthy individuals.
Aim of the inquiry: To study therapeutic effect of low frequency physical factors on the cytokines and the processes of lipid peroxidation and to confirm scientifically the efficacy of their use based on the their effect on the clinical laboratory findings.
Methods of investigation: Clinical and laboratory investigations, immunological analyses of the blood scrum cytokine levels and synovial fluid, biochemical examinations of the lipid peroxidation and antioxidant system indicators, phospholipase-A2 activity, nonspecific phosphatases and free oxyprolinc in the blood serum of patients.
The results achieved and their novelty: There was studied clinical efficacy of ultraphonophoresis with benzketozon during treatment and rehabilitation of the patients with rheumatoid arthritis. It was proved that disbalance between inflammatory and anti-inflammatory cytokines as well as lipid peroxidation activation activity in the erythrocyte membranes and blood scrum destabilized cellular membrane structures, increase in phospholipase-A2 activity and, consequently, stimulating prostaglandines, inflammation mediators, synthesis. There was shown that complex therapy with inclusion of low frequency physical factors, particularly ultraphonophoresis with benzketozon, gave marked positive effect normalizing interrelation ship between inflammatory and anti-inflammatory cytokines reducing activity of phospholipase-A2, lipid peroxidation products and rising the levels of antioxidant system indicators.
Practical value: There has been shown rationality of inclusion of the physical-pharmacological method ultraphonophoresis with benzketozon into clinical practice. The differential indicators developed for application of low-frequency physical methods of therapy for rehabilitation of the patients with rheumatoid arthritis allow prolongation of the remission, improvement of the patients life quality.
Degree of embed and economic effectivity: The practical recommendation and guidelines have been applied in the clinical practice of the out-patient special course of arthrological treatment in the Republican Rhcumatological Center, Clinical Hospital N 1, Central Hospital of Zangiota district of Tashkent province. Sphere of usage: Rheumatology, physiotherapy.

Topicality and relevance of the subject of dissertation. According to the current development of the physics of phase transitions and cooperative processes in liquids, as well as the optics of strongly fluctuating media in the world there is an actual problem of investigation of physical processes occurring in the region of critical and special points of single-component liquids and solutions, where large-scale correlations and processes of structural formation and decay on nano-size spatial and temporal scales arc manifested. Such researches arc related to the establishment of peculiarities of interaction of collective freedom degrees (order parameter) with internal freedom degrees of the medium at phase transitions. The solution of this problem is of great importance for practical realization of perspective nano-technological areas in the field of modem biophysics, biochemistry and biotechnology.
Valuable information on finding out the correlative properties of liquids on nano-dimensional scales can be obtained by investigating the integral intensity, spectral width and frequency shift of fine structure components in the spectrum of Rayleigh scattering in the vicinity of critical and special points of the liquid state. The investigation of the molecular light scattering (MLS) spectra allows to obtain unique information about the structure and kinetic properties of substances, since the spectral composition of the scattered light is defined by the dynamics of fluctuations of various thermodynamic parameters of the substance under study. However, practical realization of such investigation is a complex experimental problem. Near the critical point the registration of the spectrum’s fine structure is problematic due to the high level of fluctuations, which leads to a strong rise of the intensity of scattering on the frequency of the exciting light. According to this reason, investigations of the fine structure of light scattering spectrum near critical points of liquids arc very rare.
The relevance of the theme of the dissertation is conditioned by the necessity of establishing the regularities of the dynamics of fluctuation and structure-forming phenomena on the scales of average molecular ordering in the vicinity of critical and special points of the liquid state, as well as of developing of a spectroscopic method for invasive (contactless) identification of thermodynamically stable and unstable states of liquids. Solution of this problem is of important meaning for development such scientific and applied directions as creating a strict theory of the molecular scattering of light in strongly fluctuating media, theory of the liquid state, and formation of materials with controlled properties.
This dissertation is devoted to solving in a certain degree the problems noted in the Decree of the President of the Republic of Uzbekistan DP-1442 “On the priorities of industrial development of Uzbekistan in 2011 - 2015” of 15 December, 2010, as well as in other legislation documents in this arc.
The purpose of the research is finding out the physical mechanisms of manifestation of the dynamics of order parameter fluctuations in the spectral distribution of light scattered in the vicinity of the critical point and special point of thermodynamically unstable state of a liquid.
The scientific novelty of the dissertational research consists in the following results:
The contribution of the spatial mechanism to the dispersion of high-frequency sound velocity has been experimentally proved in the vicinity of the special point of solutions, as well as micro-heterogeneous structure of the solution below the special point temperature has been established, and the correlation radius of structural non-homogeneity ~10 nm has been determined.
The manifestation of a process of non-cohcrent scattering of hypersound due to the order parameter fluctuations in the fine structure of light scattering spectra has been experimentally determined. It has been shown that the dynamics of order parameter fluctuations can be described in terms of Landau theory for 2nd-order phase transitions. The mechanism of an excess of spectral width of fine structure components in the vicinity of the solution’s special point temperature has been grounded.
The “liquid-liquid” phase transition of structural type has been established in the solution below the special point temperature. It has been shown the applicability of Landau theory to describe the dynamics of order parameter fluctuations at the structural phase transition.
The physical mechanisms of narrowing of the spectra of anisotropic scattering near the temperature of “isotropic liquid - liquid crystal” phase transition have been revealed. The existence of a temperature interval has been experimentally proved, where the dynamics of change in spectral width and relaxation time of order parameter fluctuations can be described in terms of the mean-field approximation of Landau - de Gennes theory.
It has been shown that the correlation radius of order parameter fluctuations determines the limits of applicability of Landaua - de Gennes theory to describe the dynamics of critical phenomena in the isotropic phase of liquid crystals. The crossover character (from the mean-field to fluctuation one) of the behaviour of dynamical properties of the isotropic phase near the temperature of phase transition has been experimentally revealed.
The universality of the dynamics of order parameter fluctuations has been experimentally revealed in the vicinity of the special point of solutions, in structural “liquid-liquid” and “isotropic liquid - liquid crystal” phase transitions.
CONCLUSION
1. In order to solve the stated tasks, we used experimental setups and methods of study of the spectra of isotropic and anisotropic light scattering developed by us for researches in the vicinity of the special point of solutions and near the critical point of the phase transition in the liquid crystal. Reliable information on frequency distribution of the intensity in the scattered light spectrum was provided by using the frequency stabilized Hc-Ne laser, the high-contrast double-pass plane Fabry-Perot interferometer, and the spherical interferometer.
2. For the first time we carried out a complex experimental investigation of the fine structure of light scattering spectrum in aqueous solutions with the special point in a wide range of temperatures t and concentrations x. A correlation was revealed between the character of changing the spectrum’s fine structure and structural reconstructions in solutions with changing temperature and concentration.
3. The existence of a continuous network of H-bonds was experimentally proved in solutions of low concentration. The parameter (criterion) of its three-dimensional integrity was determined, and the limits of its destruction with changing temperature and concentration of non-elcctrolyte in the solution were defined. A change of the sign of the adiabatic compressibility derivative by temperature dps/d/ and concentration dPs/dx is the criterion, which allows to identify transitions between structurally stable states of solutions.
4. A new physical phenomenon - the negative dispersion of the hypersonic velocity - was experimentally proved in the solution with the special point. The possibility of the negative dispersion in liquids has been theoretically predicted by Vladimirskiy and Ginzburg. By the experimental magnitude of the dispersion and conclusion of Ginzburg theory (accounting the spatial contribution to the dispersion) we estimated the correlation radius of the solution’s structure, which was found to be ~10 nm;
5. It was shown that an excess of spectral width of the fine structure components of the spectrum near the special point temperature is conditioned by the additional mechanism of hypersonic attenuation due to its non-cohcrcnt scattering on order parameter fluctuations.
6. It was established that the dynamics of order parameter fluctuations in the vicinity of the special point temperature of the studied solutions can be described by Landau theory of 2nd-order phase transitions with the critical index of the generalized susceptibility y=l. Near the special point temperature the correlation radius of fluctuations q is determined by the degree of proximity to the double critical point, and it is ~2-3 nm in ЗМР-watcr solution, and ~7-10 nm in acctone-watcr solution.
7. The “liquid-liquid” phase transition of structural type was experimentally proved in 4MP-water solution below the special point temperature, as well as manifestation of this transition in temperature dependence of the frequency shift of the fine structure components of light scattering spectra in the vicinity of the point of transition. It was established that the dynamics of order parameter fluctuations in “liquid-liquid” phase transition is described by Landau theory. Near the temperature of the structural phase transition the correlation radius of fluctuations is ~5 nm.
8. It was established that while approaching the temperature of “isotropic liquid - liquid crystal” phase transitions, the dynamics of the narrowing of the spectrum of anisotropic light scattering and the rise of the relaxation time of order parameter fluctuations can be described by Landau - de Gennes theory with the critical index of the generalized susceptibility y=l. It was shown that the correlation radius of order parameter fluctuations determines the limits of the theory applicability to describe the dynamical properties of the isotropic phase.
9. It was experimentally shown that Landau - de Gennes theory describes the dynamics of order parameter fluctuations in the temperature interval, where the correlation radius of fluctuations q is 3£o<£<l Oco (^0.6 nm is about the length of the molecule). In the very vicinity of the phase transition temperature, where £>lO£o, the narrowing of the anisotropic light scattering spectrum and the excessive rise of the relaxation time is conditioned by the crossover (from meanfield to fluctuation) character of the behaviour of dynamical properties of the isotropic phase.
10. It was shown that the regularities of changing the spectral composition of the scattered light near the critical and special points - 1) narrowing of the spectrum of the anisotropic light scattering near the temperature of the phase transition in liquid crystals, 2) excessive spectral broadening of the fine structure components in the vicinity of the solution’s special point, 3) singularity of the temperature dependence of the frequency shift of fine structure components in the vicinity of “liquid-liquid” phase transition - arc conditioned by the dynamics of the correlation radius of order parameter fluctuations, which is of the universal character.

 Increased interest in the problems of mechanics of coupled fields, primarily to electromagnetoelasticity, caused by the needs of today's technological advances in various industries and the development of innovation technologies. The issues of motion of a continuum with electromagnetic effects fill a highly important place in the mechanics of coupled fields.
One of the main directions of development of modern solid mechanics is a development of the theory of conjugate fields and, in particular, the theory of the electromagnetic interaction with deformable medium.
The mechanism of interaction of an elastic medium with the electromagnetic field is diverse and depends on the geometrical characteristics and physical properties of the body under consideration.
In particular, this mechanism gets some specifics when considering the problems of thin plates and shells having anisotropic conductivity.
In creating optimal structures in modern engineering, widespread use is made of thin-walled shells and plates as structural elements in which effects of nonlinear electromagnetic interaction with magnetic fields are significant.
Effects of the coupling of mechanical displacements of conductive bodies with the electromagnetic field are conditioned by the Lorentz ponderomotive forces. The Lorentz forces depend on the speed of the conductive elements of a continuous medium and the external magnetic field, the magnitude and orientation of the conduction current in reference to external magnetic field. Significant effects of ponderomotive interactions occur for high-frequency oscillations at large amplitudes of displacements, pulsed magnetic fields and current-carrying elements. It is for these conditions are first necessary to develop mathematical foundations of magnetoelasticity and applied methods for solving certain classes of problems. Among these classes of problems, first of all, we note the problem for currentcarrying thin anisotropic plates and shells placed in a strong external magnetic field, as well as the problem of nonlinear magnetoelastic vibrations of thin-walled elements in a magnetic field.
On the basis that specific magnetoelastic effects found in the study of nonlinear coupled problems, it seems urgent development of numerical approaches to solving problems related to the magneto-anisotropic flexible current-carrying plates and shells having anisotropic conductivity under the influence of non-stationary electromagnetic and mechanical stresses. In studies of nonlinear magnetoelasticity problems of special interest is determination of the stress-strain state of current-carrying plates and shells on exposure to variable electromagnetic and mechanical fields with regard to anisotropic electroconductivity, magnetic and dielectric permittivity.
Demand of these problems and interest in ones is conditioned by wide application in modern engineering as constructive elements of thin shells and plates, which are exposed to strong magnetic fields. These problems occur in modern technology, where such structures are used as protecting or bearing elements for shielding external fields of strong magnetic equipment. This interest is conditioned by the need to solve problems of electromagnetic compatibility with the development of modern measuring systems, computer devices, measurements of weak pulsed fields on the background of large fields, the development of the protection of personnel from electromagnetic effects, etc.
Topicality and demand of the subject of dissertation in the formulation and solution of problems in accordanse with the Law of the Republic of Uzbekistan “On providing an electromagnetic compatibility” (1999, № 1, art. 16, 2003, № 5, art. 67, 2013, № 18, art. 233).
The electromagnetoelasticity coupled problems of anisotropic plates and shells having anisotropic conductivity are of scientific interest in terms of both theory and applications. The matter is that in the case of thin anisotropic bodies having anisotropic conductivity it is possible to solve optimal problems of magnetoelasticity by the variation of all physical-mechanical material parameters ofbody.
In particular, when mechanical and geometric parameters of the problem are constant, using variation of anisotropic electrodynamic parameters it is possible to obtain constructive elements with qualitatively new mechanical behavior. It should be noted, that recently the materials with new electromagnetic properties were created. These materials can be use in different areas of new appliances at creation of new technologies.
Purpose of research is the development of the theory of nonlinear magnetoelasticity current-carrying anisotropic bodies having anisotropic electroconductivity, mathematical modeling and the decisions of the new class of magnetoelasticity, which will explore the stress-strain state and analyze the electromagnetic effects in orthotropic shells of revolution with the ultimate orthotropic conductivity, magnetic and dielectric permittivities.
Scientific novelty of disscrtational research consists in the following: there was first formulated the geometric nonlinear statement of the conjugate dynamic problem of magnetoelasticity to the current-carrying shells taking into account the anisotropic electrical conductivity, magnetic and dielectric permittivity;
the nonlinear two-dimensional magnetoelastic model for the current-carrying orthotropic shells with finite orthotropic conductivity, magnetic and dielectric permittivity was first obtained;
resolving system of equations which describes nonsymmetrical deformation of flexible conductive shells of rotation, which have orthotropic electroconductivity variable in two coordinate directions of hardness impacted by the nonstationary electromagnetic as well as mechanical forces was obtained;
coupled resolving nonlinear differential equations system of magnetoelasticity of flexible current-carrying orthotropic shells of rotation of arbitrary meridian due to orthotropic electroconductivity, magnetic and dielectric permeability, under the nonstationar impact was obtained;
the methods and algorithms for solution of coupled dynamic problems for magnetoelsticity of orthotropic shells of rotation subject to finite orthotropic conductivity, magnetic permeability and dielectric permittivity in nonlinear statement are for the first time developed;
new effects caused by connection of mechanical deformation fields with electromagnetic fields due to final orthotropic electroconductivity, magnetic and electrical permeability were discovered;
the stress-strain state of a current-carrying orthotropic shell with orthotropic conductivity was optimized for the selected direction and magnitude of a foreign current density.
Conclusion
1. The mathematical formulation of the problem of the nonlinear coupled dynamic magnetoelasticity of current-carrying shells taking into account the anisotropic electrical conductivity, magnetic and dielectric permittivity was made.
2. A nonlinear two-dimensional model of current-carrying magnetoelasticity orthotropic shells with respect to orthotropic conductivity and magnetic permittivity in the geometrically nonlinear formulation was made. It was assumed that the main directions of orthotropic material properties of the shell coincide with the directions of the corresponding coordinate axes, as well as orthotropic body is linear relatively to the magnetic and electrical properties.
3. On the basis of the quadratic version of geometrically nonlinear theory of shells and plates, coupled allowing system of nonlinear differential equations of magnetoelasticity was built. This system describes the stress-strain state of flexible current-carrying orthotropic shells of rotation of arbitrary meridian under the influence of time-dependent mechanical and electromagnetic stresses due to orthotropic electrical conductivity, magnetic and dielectric permittivity.
4. The development of the technique and algorithm for numerical solution of new class of coupled dynamic problems of magnetoelasticity which allows us to investigate the stress-strain state of the current-carrying orthotropic shells of rotation with regard to orthotropic electrical conductivity and magnetic permittivity in geometrically nonlinear formulation. On the basis of the developed method the stress-strain state of isotropic current-carrying circle plate and a conical shell under the influence of mechanical force, an external electric current and an external magnetic field was performed. As follows from the results of comparisons with the increase of duration of forces action and a decrease of the time step the difference between the values of deflections and stresses in various steps increases slightly. The numerical data obtained for the fourth and fifth approximations practically coincide indicating a satisfactory convergence of the iterative process. Results of the comparisons in the isotropic setting with the data of other authors show the possibility of using the proposed approach for the study of stress-strain state of flexible current-carrying orthotropic shells of rotation having orthotropic conductivity.
5. The influence of taper on the nonlinear behavior of orthotropic shell was considered. It was revealed that the interaction of magnetic induction and shear force causes extreme values of deflection and stresses, electric field and magnetic induction intensity. Note that the magnetic induction and the shear force are given on the left contour of the shell (boundary conditions) and at the same time shear force and the normal component of the magnetic induction are in opposite directions. It was found that a decrease in the cone angle leads to absolute values of deflection and stresses, electric field and magnetic flux density increase. This fact illustrates the interconnection of electromagnetic and mechanical fields. It was revealed that the cone angle equal to six degrees proved to be critical for the considered geometrically nonlinear shell at the selected loadings. Further reduction of the angle leads to buckling of the shell.
6. The stress-strain state of flexible shells in nonlinear formulation based on comparison of the solutions obtained for the current-carrying orthotropic cone of beryllium and current-carrying isotropic cone of aluminum, as well as for the isotropic cone of aluminum in the absence of a magnetic field and the external current was investigated. In all three cases the distribution of the non-linear deflection and its maximum values occur in the left contour of the shell. At the same time in the case of beryllium orthotropic cone and the isotropic cone of aluminum, considering the magnetic field maximum values of deflection differ by about two times. It was revealed that in the case of the isotropic cone without influence of the magnetic and electric fields, the deflection increases significantly. This is because in the absence of an electric field acting on the shell, the tensile strength of the tangential component of the magnetic induction, and the tangential component of the Lorentz force equals to zero. The results of decisions received in linear and nonlinear statements are compared. It was found that the difference between the results of solutions of linear and nonlinear formulations increase with decreasing of angle of the cone. Analyzing the results obtained it is possible to consider the influence of the geometric nonlinearity on the stress- strain state of orthotropic shells in comparison with the linear theory.
7. Numerical results for orthotropic beryllium cone of variable thickness for different values of “a”, parameter characterizing variability of thickness in the meridional direction were obtained. It was found that increasing the value of “a” increases the deflection, peripheral stresses of the shell, Maxwell stresses, etc. As can be seen from the results variability of thickness has a significant effect on the stress-strain state of the shell, which should be taken into account in practical calculations. The stress-strain state of a current-carrying flexible orthotropic beryllium cone of variable thickness for different types of the contours fixing of the shell was investigated. From these results it is clear that the boundary conditions of the shell contours fixing significantly affect the value and distribution of deflections, shear forces and bending moments, Lorentz forces, the magnetic induction and electric field intensity.
It was revealed that the maximum deflections and bending moments, Lorentz forces, the magnetic induction and electric field intensity arise at "hingesliding" boundary conditions. It was found that in the presence of magnetic induction on the left contour of the shell the values of deflections, bending moments , Lorentz forces, the magnetic induction and the electric field intensity is much higher compared to the presence of an electric field. Due to these results we can consider the influence of boundary conditions on the interconnectedness of mechanical and electromagnetic fields.
8. It was found that with increasing of magnetic induction the deflection and stress of the shell also increases. It was established that an increase in external magnetic field induction also increases induction of the internal magnetic field. This corresponds to a real physical processes occurring in the shell and in turn confirms the accuracy of the results.
It was shown that by choosing the value of the density and orientation of the external current due to orthotropic conductivity it is possible to optimize the stress state of the shell which is under the influence of non-stationary electromagnetic and mechanical fields. It was revealed that the increase in the value of an external electric current leads to an increase in the values of deflections and stresses of the shell, tangential and normal components of the Lorentz forces. Thus choosing the direction and magnitude of the electric current density one can achieve minimum deflection and stresses in the shell.
9. In the considered problems the dependences of values for characteristic functions of the stress-strain state of the electromagnetic parameters, in particular from the orthotropic electrical conductivity and of orthotropic of material properties which allows one to evaluate the impact of the interconnection of fields were made. Using the resulting system of coupled equations of magnetoelasticity of orthotropic shells of rotation, developed techniques for solving problems in the theory of non-stationary current-carrying shells considering orthotropic electrical conductivity in geometrically nonlinear formulation allows one to solve a new class of problems. At the same time the influence of orthotropic electrical conductivity, magnetic and dielectric permittivity of the material and the actual working conditions of structural elements are taken into account more fully that allows one to make a choice of rational geometrical, mechanical and electromagnetic parameters to improve the reliability of the construction.

Topicality and demand of the subject of dissertation. According to the Resolution of the President of the Republic of Uzbekistan PQ-1442 «On the priorities of development of industry of Uzbekistan in 2011-2015» from December 15, 2010 rising of industrial manufacturing efficiency is overriding problem. Thereby, the consistent decrease of manufacturing costs and the cost value of semiconductor high-power devices (voltage suppressors, high-frequency rectifier diodes) which are manufactured by JSC «FOTON», provides for studies, aimed at improvement of their parameters and reliability as well as technological optimization, are the most important pre-requisites facilitating increase in competitiveness of manufactured devices and ensuring existing markets and new markets.
In the field of the protection of electronic equipment and prevention of failure of electrical equipments by pulse overvoltages among scientists of leading foreign countries USA, Canada, Holland and Japan tasks of research and development of high-voltage suppressors, as well as stabilizing devices based on power diodes are demanded.
These power diodes are widely used in power conversion devices, power supply systems and industrial process control systems. For their manufacturing diffusion technology of doping of silicon with boron and phosphorus is used, which is widely used for the manufacture of high-voltage diodes. However regarding the low-voltage voltage suppressors does not allow to get low differential resistance which can be obtained using the impurity providing a dramatic difference of the carriers concentration at the boundary of the p-n junction. Solving this problem requires new physical approaches that enable to obtain the high-concentration source - diffusant, which can be manufactured by use of arsenic. Moreover the efficiency of the power diodes is determined by the sharpness of the characteristics at breakdown voltages and nominal coefficient of suppression. In operating mode, power diodes under the influence of powerful pulses generate heat and their optimization is possible based on the physical analysis of heat transfer throughout the length of the structure, including the contact areas.
The demand of dissertation is derived from the need to implement advanced technologies, devices for grading and protection of electronic equipment, improve withstand impulse power that is associated with tasks requiring a focused approach to problems of reduction the technological failures and increase reliability, extend the scope of applications of power diodes, and reduce dynamic power losses.
This dissertation aimed at development of the manufacturing technology of low-voltage voltage suppressors with small scatter of the breakdown voltages and low differential resistance in both forward and reverse directions, development of radiation technology providing optimization of the breakdown voltage, increasing performance and improvement of quality of high-frequency diode.
At the same time, in a number of cases, these devices themselves need in protection from unexpected increase of current in circuit, which requires development of current limiters with characteristics reversible after influence of pulse of current. Based on the abovementioned, it is timely and actual to study in a comprehensive way both parameters of selected samples under research, and physical aspects of the production technology (for example, diffusion and radiation methods), aimed at design and technology optimization at manufacturing of the selected objects under research and, hence, obtaining optimal combi-nation of their parameters, including those related to radiation hardness requirements.
Purpose of research is development of optimized diffusion technology aimed at obtaining silicon diode structure with reduced differential resistance and enhancement of quality and reliability of high-frequency rectifier diodes and voltage suppressors under radiation.
Scientific novelty of disscrtational research consists in the following:
for the first time, technology is developed for manufacturing of low-voltage suppressor (less than 7 V) based on silicon p -n - structures doped with arsenic to apply for protection of power supply units;
for the first time, the method was developed for obtaining high-power silicon rectifier-suppressor diodes (10A) based on silicon p -p-n-n -structures with effective heat-removing contacts, which can be applied as rectifier, suppressor and blocker diodes;
the method is developed for obtaining stable to temperature ohmic contact to high-power diode with p -p-n-n -junction composed of three layers, one of which is tungsten and two others are silver layers, annealed at 450 “C, and copper disk galvanically covered with silver is selected as a heat-removing compensator;
universal double-generator method is developed to measure voltage suppressor characteristics with three times lower errors compared to those for singlegenerator method;
for the first time, current limiter with controlled operation current is designed based on gallium arsenide and contains first type conductivity semiconductor base, second type conductivity thin layer with two ohmic contacts located at some certain distance from each other and supplied with output electrodes;
the method is developed to determine voltage limitation efficiency via diode’s resistance dependence on reversed current density in the region of breakdown in a wide range of voltage values;
heat models are developed based on heat transfer and heating ofp-n-]unction when it is connected and pulse voltage is applied, assuming that the junction is heat potential and heat flow generator;
technological method is developed aimed at determination of appropriate irradiation mode, allowing optimal combination of voltage suppressor and high-frequency diodes parameters;
for the first time, protection device for electronic equipment is designed with option to indicate instant of voltage suppressor failure.
CONCLUSION
1. Low-voltage suppressors manufacturing technology is developed based on lube diffusion from high-concentrated arsenic source ensuring low deviation in breakdown voltage and low differential resistance.
2. The method is developed to obtain high-adhesive and heat dissipating oh mic contact to silicon high-power diodes. This methods includes spraying of tungsten and silver thin (0.1-Ю.З pm) layers on both surfaces ofp-n-yunction plate, and their consequent alloying with silver-plated copper heat compensator. This contact is used in developed blocking diode, which prevents failure of occasionally blocked unit of power station.
3. The method is developed for early stage rejection of voltage suppressors before installing them in casing by means of newly introduced parameter «efficiency coefficient», which is based on voltage suppressor resistance dependence on current in the breakdown mode.
4. The voltage suppressor heat model is developed to calculate and implement optimal sizes of crystal heat-removing compensators, to determine location of its active region relatively to the ohmic contacts, and, based on its characteristics, to describe it as temperature voltage generator and heat flow generator.
5. The improved double-generator method is developed to measure voltage limitation in high-power (pulse currents exceed dozens of Amperes) voltage suppressors, which can be used in measurements of reverse voltage and pulse component formed by current generator. Total measurement error occurs to be -2%, w hich is three times less than that of known single-generator method.
6. The unit for electronic equipment protection is developed based on voltage suppressor, providing automatic connection-disconnection of consumers in case of circuit overload.
7. The radiation technology is developed to optimize life-time of minority charge carriers and reverse resistance recovery time, breakdown voltage in high-frequency rectifier diodes and voltage suppressors.
8. Technological methods for calculation of reverse current and direct voltage drop, as well as volume charge layer thickness are developed to allow determination of optimal junction characteristics of high-frequency diodes related to gamma and electron irradiation dose.
9. Gallium arsenide based current suppressor is designed for low-voltage suppressor protection with reversible breakdown up to 14 V.
10. Results obtained in this dissertation related to voltage suppressor manufacturing technology and pulse parameters study methods are implemented in production at JS “FOTON”.

The aim of the research is working out methods and facilities for providing indicators of electricity quality at steady-state asymmetric modes in low-voltage electrical power grids
Scientific novelty of the research is as following:
development of a method for estimating additional losses in the case of longitudinal and cross asymmetry in low-voltage electrical networks;
there has been worked out the construction of electromagnetic converter of three-phase asymmetrical current into voltage;
there has been worked out the method for providing quality of electricity with the use of electromagnetic converter of three-phase asymmetrical current into voltage;
there has been designed a device “Malika-01” assigned for measuring indicators of electricity quality in low voltage electrical power grids has been designed.

The aim of the research thesis is revealing peculiarities of the technology of manufacturing semiconductor coordinate-sensitive detectors of ionizing radiation based on single-crystalline silicon wafers of large diameter as well as investigating their functional characteristics.
Scientific novelty of the research thesis: The scientific novelty of the study is as follows:
A technique of mechanical and chemical processing of the original wafer of large diameters has been developed in order to ensure high flatness;
A two-side diffusion technique has been developed, which decreases the time of diffusion two times in large-diameter silicon structures;
A technological map for manufacturing of large-size coordinate-sensitive detectors based on Si (Li) p-i-n structures with 8, 16 and 32 bands has been developed;
8-band semiconductor coordinate-sensitive detector has been developed on the basis of Al-aGe-pSi-Au heterojunction structures with 20% advanced sensitiveness compare to analogues;
A semiconductor coordinate-sensitive 8-band semiconductor detector based on the Al-aGe-pSi-Au heterojunction with a front-ohmic contact and a rear contact with a Peltier cooling element, which reduces the leakage current by half, is created.

The aim of the research is design of sophisticated algorithms for choosing Ground Wires on multi-wire Overhead Power Transmission Lincs, which allow to take into account parameters along the whole length of the line
Scientific novelty of the research is consisted of the following:
dependence of calculated values of currents in wires at asymmetrical short circuit modes on parameters of multi-wire Overhead Power Transmission Lines (tower geometry, span length, types of phase and ground wires) on the basis of the use of sparse matrices was determined;
equivalent resistances of Ground Wires on Overhead Power Transmission Lines with taking into account tower total grounding resistances were improved;
algorithm for thermal stability calculations of Ground Wires to asymmetrical short circuit currents on the base of presenting Overhead Power Transmission Lines as multi-wire system was improved;
possibility of reducing current levels in Ground Wires with embedded Optical Cables at asymmetrical faults on the base of tower grounding resistance insulations made on substations was developed.

Subjects of research: the basic object of research is silk fibroin and wool keratin. For comparative experiences is chosen copolymer of acrilonytrilc. As the solvents the systems 2,5 M LiCl-DMFA, 2,5 M NaOH-water and 7,7 M NaCNS-watcr arc used.
Purpose of work: consists in revealing laws of dcformational and orientational structure formation of fibroin and keratin at the non-newton stream of solutions and ions electrodialysis also definition of clcctroconductivity characteristics of received gels and besieged samples, containing residual ions.
Method of research: rheooptimetry, birefringence, dispersion optical rotation, polarization ultramicroscope, viscosimetry, potentiometry, electrodialysis, ampermetry.
The results obtained and their novelty': the features of education of solutions of fibroin and keratin in the ion containing the solvents are revealed and the critical parameters for a choice of a biopolymeric solution allowing to realize non-newton stream and ions electrodialysis arc established; representing structural organizations and interactions of electrodialysis for the first time arc found out the hysteresis effects at non-newton stream of solutions generated in the shift and longitudinal fields; opportunities of dcformational and orientational structure formation of fibroin and keratin for the first time are revealed at the non-newton stream of solutions with intensive removal of ions by means of electrodialysis; the conditions of reception gels and besieged samples of fibrillar proteins with high degrees of the factor of orientation of circuits and small quantity of residual ions determined; Arc determined of electroconductivity characteristics of received gels and besieged of fibrillar proteins depending on a degree of ordering macromolecules and contents of ions in samples; the installations rheooptimetry, complemented with electrodialysis for the investigations of structure formation arc assembled at the non-newton stream in conditions of intensive removal of ions.
Practical value: revealed of dcformational and orientational of behaviour of of fibroin and keratin and also them hysteresis effects in the non-newton stream have the important meaning in development of fundamental representations about dynamics ordered structure formation of fibrillar proteins from solutions; the revealed laws of education of solutions, gels and besieged samples of fibroin and keratin at the presence of ions of salts and alkalis, and also them electroconductivity characteristics can be useful to development of scientific principles of processing fibrous wastes of silk and wool with reception of biomaterials with specific physical properties; the specially assembled experimental by generation non-newton stream and ions electrodialysis represent the large interest for research ordered structure formation of biopolymers with regulation of the contents of ions, and also for reception gels and besieged samples with electroconductivity properties on their basis.
Field of application: dynamics high ordered structure formation of fibrillar proteins in a flow; clcctrophysics polymeric gels and compositions; ions electrodialysis; processing of natural polymers; polarization optics and rheology.

The aim of the study is controlling magnetic properties of silicon with magnetic nanoclustcrs depending on their concentration and electrical parameters in a wide range of temperatures under different external effects.
Scientific novelty of research consists of the following:
optimal low-tcmpcraturc step-by-stcp technique of diffusion doping was developed that allows the formation of nanoclusters of manganese atoms with magnetic properties in the entire bulk of silicon sample with a controlled distribution and parameters.
the technique of boosting thermal stability of the parameters of silicon doped with atoms of manganese at high temperatures was proposed which is due to the formation of nanoclusters of manganese atoms;
a high negative magnetoresistance in silicon at room temperature was revealed due to the increase in the concentration of magnetic nanoclusters of manganese atoms up to 10I5cm'3;
a linear increase of the negative magnetoresistance in silicon with magnetic nanoclusters of manganese atoms was determined by the increase in the value of the magnetic field;
the effect of quenching of the negative magnetoresistance under the influence of the integral and infrared light due to reduction of the negative magnetoresistance down to 100 times that have strong magnetic moment and the charge state;
a transition to the ferromagnetic state of silicon at low temperatures 30 K, due to the streamlining of the orientation of the magnetic spins of the cluster (Mn)4, having a magnetic moment was detected;
the calculation of the magnetic moment of nanoclusters of manganese atoms by using the expression using the values of magnetization of silicon () determined from experimental results at low temperatures 10 К was carried out;
a linear decrease in the magnetization of silicon with increasing temperature due to the disordering of the spins of nanoclusters with an increase in (kT) of energy was detected.
a possibility or controlling the magnitude ot the negative magnctoresistancc of 6-fold at 240 К in a wide range of electrical (0,1-600 V/cm) and magnetic (0,2-2 T) fields.

The article provides a comparative analysis of turbulence models by numerically simulating a swirling flow inside a rotatable pipe. To
solve this problem, the Reynolds averaged non-stationary Navier-Stokes equations in a cylindrical coordinate system were used. To find the Reynolds voltage, the turbulence model was used the most popular semi-empirical turbulence model. Comparison is made between models of different approaches to turbulence SSG / LRR-RSM-w2012 and νt-92. The numerical results obtained on the basis of turbulence models are compared with the well-known experimental results of Reich and Beer (1989)

The actuality and necessity of the thesis theme. At present in the world on the semiconductor physics intensive developing branch the polycrystalline silicon semiconductors lead the important role. Because of the raw materials arc relatively cheaper and stronger than other ones to the irradiation rays flow in the world semiconductor instruments based on polycrystalline silicon, solar elements and also integral micro schemes design is being developed intensively. As the physical properties revealed in concrete conditions of the polycrystalline silicon depends on its between grain boundaries regions volume, the profound of the physical processes occurring in this region is being one of the important tasks.
In our country in the years of independence an attention to study the developing semiconductor physics branch, namely, solar elements and semiconductor instruments creation, which have a quality index and meet to international standards requirements, have been drawn. In this field the essential results on studying methods of the controlling physical processes of the polycrystallinc silicon in the two contacting grain boundaries region and also based on applying them to the solar elements arc being reached.
Creation or the semiconductor instruments and solar elements, which arc relatively cheaper and stronger to outside affects including the stable to the temperature and irradiation rays beam by improving the electrical and optical characteristics of polycrystallinc silicon semiconductors, is a important task. In this field to realize the objective scientific investigations, including in the following directions arc one of the important problems: definition the microstructure of the two contacting between grain boundaries region and impurity states; designation of modem methods for definition of their electrical and optical characteristics with taking into account the physical and chemical properties of volume defects and between grain boundaries regions of polycrystallinc silicon; definition the related laws which the electron-hole pairs formation and transition in impurity states on between grain boundaries region when light rays or temperature changing process and their affect to electrical and photoclcctrical properties of polycrystalline silicon p-n structures; definition of affect to between grain boundaries region impurity atoms microstructure and electronic properties; creation and production of new type energy transformations via controlling physical processes in between grain boundaries regions. The investigations mentioned above explain actuality of the present thesis topic.
The present thesis investigations arc the works to realize in Decision "PQ-1442" of President of Uzbekistan Republic "On the priory directions of development of Republic of Uzbekistan industry in 2011-2015", and other legal and regulatory documents connected with this decision.
The purpose of the investigations is laws establishing of dependence of the electrical physical properties of polycrystallinc Si and photoelectrical characteristics of p-n structures based on impurity states localized in grain boundaries region and volume defects.
The scientific novelty of investigations is following:
it has been found that rough surface formation of boundaries abundant overhangs and micro cavities in grain boundaries region is caused with uneven distribution of impurity in volume of the grain, namely with concentrate increase of each of their impurities from center up grain boundary;
it has been revealed that width of united layers of two contacting grains, where the ionization fact of localized traps in temperature changing process with taking account of ionized traps energy that leads to change potential barrier height in range of -0,3-0,9 eV and to decrease charge carrier density, is about nanometer;
the multilayered interface model of two contacting grains and equivalent electric scheme which allows to define the electrical properties of grain boundaries has been constructed;
the adsorption and desorption phenomena in grain boundaries region have been founded;
the impurity thermal-voltaic and thermal-photovoltaic effects occurring regularity in homogeneous polycrystalline Si and p-n structures, on its base and also in mono crystalline Si with p-n transition conducted with formation of electron-hole pairs when deep impure states participate, has been installed;
the model of formation of p-n transition in grain boundaries region.
CONCLUSION
Based on the carried out physical processes investigations in polycrystallinc Si between grain boundaries and thermal-voltaic and thermal-photovoltaic effects phenomena we can make the following conclusion:
1. The many layers junction of two contacting grains model whereby each of grains consists from mono crystalline com surrounded with defects region, dislocations and other structure violations and also uniformly distributed on island surface of metallic components and micro region in the form of protrusions and hollows has been designed.
2. The non monotonic character of specific resistivity, p, mobility, p, concentration, n, temperature change of charge carriers conditioned by combined affecting grains and ionized localized traps connected with impurity states or defects in between grain boundaries, has been found.
3. It has been confirmed experimentally that localized traps density increasing leads to change of potential barrier height, <p, from 0,3 up to 0,9 eV and to growth of the quantity, p, and also to decreasing of the basic carriers concentration.
4. The equivalent electrical scheme allowing to define the between grain boundaries electrical properties in totally and each of theirs micro regions components based many layers junction of two contacting grains model have been proposed.
5. The adsorption and desorption manifestation conditions of the several alkaline metals and their affect to micro structure and between grain boundaries electronic properties have been installed. Namely, the between grain boundaries alkaline metals desorption in curing process leads to change of sign <p and conductivity type as thin layer on polycrystalline Si surface, and the alkaline metals diffuse by polycrystallinc Si substrate surface leads to their adsorption on surfaces of two contacting grains.
6. It has been shown that in range of temperature ~30(R800 °K the dark current and voltage arc changing on comparison of mono crystalline samples complex manner because of charge carriers capture in traps and their drift by traps in localized traps ionization process in between grain boundaries region.
7. The p-n transition model in between grain boundaries which explains charge carriers transition mechanisms in them and dark current and photocurrent formation conditioned with charge carriers capture and emission in traps has been proposed.
8. It has been shown that impurity thermal-voltaic and thermal-photovoltaic effects manifestation in p-n structures on base polycrystallinc and mono crystalline Si on heating and lighting arc conditioned by electron-hole pairs generation processes with participation deep impurity states.
9. The investigation methods of impurity states in between grain boundaries region have been modified. It has been shown that by electronic properties estimation of between grain boundaries applying the heat emission model it must be taken into account the traps total conductivity and current Jss, which arises in the charge carriers capturing and emission processes.
10. It has been shown that the designed new leggier method with using swift defunding elements allows us to obtain p-n structure at the same time as with p and n types samples, and as with simplification of the method to increase reproducibility of technological process.
11. It has been created the method for semiautomatic definition the temperature dependences of p-n structures electric physical characteristics with scanning possibility with light ray with given wave length and diameter from ~10 up to 400 mkm on sample surface.
12. The diffusion setting allowing simultaneously to make the different regions designed for construction heat and solar energies converters in the different parts of mono and polycrystallinc Si plates has been designed.

Object of research: is instrumental structures with Schottky barrier on basis of GaAs (GaP, InP), as subject of research arc selected transition process of the characteristic of metal металл-А3В5, generated by fine metals and amorphous films TiBx under the influence of 60Co gamma-radiation, microwave radiation and rapid thermal treatment.
Purpose of work: clarifying the mechanism of reproducibility increasing and stabilization of instrumental structures on basis of GaAs, GaP and InP with Schottky barrier generated by amorphous films TiBx.
Methods of research: auger-electron spectroscopy in aggregate with ion etching (Ar*, En=l kiloelectronvolt), X-ray structural analysis, atomic-force microscopy. 60Co gamma-quantum irradiation conducted on installation MPX-/-25M, and microwave treatment with magnetron radiation on a frequency/=2,45 GHz with 1,5 Vt/sm2 output power density. Voltage-current characteristic investigated on standardized automated curve tracers.
The results obtained and their novelty: conducted the analysis of the mechanism of mechanical stress on films and contact structures against the A3B5, which allows clarify the regularity of processing factors' impact on mechanical stress of contact structures. Developed the physic-technological basis of contacts generating against A3B5 including rapid thermal treatment, which allows to control contact characteristic by the impact on phase formation process and interface characteristic. Developed the new technological approach to preparation of autoepitaxial films of InP n type, growing by the method of liquid-phase epitaxy on n*-InP porous bottom layer and ohmic and barrier contacts to them using the amorphous interstitial phase of TiBx.
Practical value: findings on external action tolerance of the semiconductor instrumental structures with Schottky barrier on basis of A3B5 can be used in creating the semiconductor instrumental structures with Schottky barrier on basis of A3B5.
Degree of embed and economic effectivity: findings of research arc used in research scientific works and engineering developments in “ORION” research institution at developing and preparing microwave diode with Schottky barrier.
Field of application: solid-state microwave electronics, semiconductor instrument making, the technology of microwave semiconductor instruments.

Ushbu maqolada aylanish sirtlarining yuzini hisoblash usullari keltirilgan va unga doir misollar ham berilgan.

Subject of research: homogeneous processes with independent increments and the generalised renewal processes.
Aim of the research: obtaine the complete asymptotic expansions for the distribution of the number of a rectilinear strip by trajectories of homogeneous process with independent increments and the generalised renewal process.
Methods of research: in the dissertation a used the analytical factorization method.
The results achivved and their novelty: all main outcomes of the thesis are new and consist of the following:
- complete asymptotic expansions in t —> oo for the distribution of the number of crossings of a rectilinear strip till the moment t by a trajectory of homogeneous process with independent increments have been obtained. Thus it is supposed that strip borders grow together with t and are imposed on condition process, basically, Kramer’s type;
- the first members of asymptotic decomposition are written out in an explicit form and the algorithm of calculation of the subsequent members is specified;
- the results specified above are transferred in case of the generalised process of restoration.
Practical value: the thesis has theoretical character.
Field of application: the received results can be used at the decision of various problems of mathematical statistics, the theory of mass service, the theory of storage of stocks and others.

Uzbekistan is a country endowed with a variety of medicinal plants with strong potential
for therapeutic application, Ferula assefoetida l. is called ferula is one of the most
popular medicinal herbs. It is important active ingredient responsible for the biological
activity of ferula, through the major activity is anti-inflammatory. This analysis was
aimed to determine analysis compound of ferulic acids analysis using high performanceliquid chromatography (HPLC), LC-20 Prominence, Shimadzu, column C-18 250 х 4,6
mm, 5 mcm; acetonitrile: acetic acid: aqua bides as mobile phase, flow rate 1 ml/min
and detection at 320 nm. Thus the analytical method using HPLC for ferulic acid were
feasible for quantitative analysis. As a result of the research, the content of dry extract
was 0,01% of the content of ferulic acid.

The urgency and relevance of the dissertation topic. Studying properties of integro-differential operators and their applications to solve nonclassic problems for partial differential equations has different and important applications. Therefore, development of researches on integro-differential operators of fractional order and their application is one of the important problems.
The aim of the research work is to solve direct and inverse problems for partial differential equations with integro-differential operators, to study properties of integro-differential operators and their applications to solve nonclassic problems for elliptic equations.
Scientific novelty of the research work is as follows:
the unique solvability of nonlocal problems for partial differential equations of fourth order with integro-differential operators is proved;
for the first time basis properties of root functions of spectral problems, corresponding to the Samarskii-Ionkin type problems is studied;
the necessary conditions of the existence of inverse problems of the identification of source-function for the partial differential equations with fractional order operators are justified;
regular solvability of problems for mixed type equations of fractional order with the integral matching condition is proved;
properties of integro-differential operators of fractional order of the Hadamard and Hadamard-Marchaud type are studied and applied to solve boundary value problems for elliptic equations; 
the method of the solving boundary value problems, and also the Bitsadze-Samarskii type problems in the class of harmonic and smooth functions for equations of elliptic type with generalized boundary value operators of fractional order is worked out.