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Purpose. Development and use of a mathematical model of the stages of formation of high-voltage pulse discharges in gas bubbles in the discharge gap «rod-plane» to identify the features of the electric field intensity distribution in the reactor and determine the current density in the load during disinfection and purification of liquid media by high-voltage pulse discharges and find the most rational treatment. Methodology. To achieve this goal, we used computer modeling using the finite element method as a method of numerical analysis. An experimental reactor model was created that takes into account the dynamics of discharges in gas bubbles in water. The equations describing the system include the generalized Ampere equation, the Poisson equation and the electric displacement equation, taking into account the corresponding initial and boundary conditions, as well as the properties of materials. The dependence of the potential of a high-voltage electrode on time has the form of a damped sinusoid, and the specific electrical conductivity in a gas bubble is a function of time. Processes occurring at the front of the voltage pulse from 0 to 20 ns are considered. Results. It is shown that with an increase in conductivity and high-voltage potential to amplitude values in a gas bubble, the electric field strength in the water layer in the reactor reaches 70 kV/cm, and it is in the water layer that there is a strong electric field. The calculations show that already by 19th ns the density of conduction currents in water prevails over that of displacement currents. At the same time, additional inclusions in the water significantly affect the distribution of electric field strength and current density, creating a significant difference in their values at the boundaries of the interface between the bubble, conductive element and water. Originality. A simulation of the dynamics of transient discharge processes in a gas bubble and a layer of water with impurities was carried out, including an analysis of the distribution of the electric field strength and current density in a system with rod-plane electrodes in the phase transition section of a gas bubble-water. This approach allows us to reveal the features of processes in reactors and to investigate the influence of phase transitions on the distribution of electrophysical quantities. Practical value. Computer simulations confirm the prospect of using nanosecond discharges generated in gas bubbles within a volume of water for widespread industrial use and are of great interest for further experimental and theoretical research. References 25, figures 9.

An original thermal-hydraulic method for optimizing the thermal resistance of thermal conductivity of fuel rod matrix upgrades has been developed to achieve the maximum burnup depth of nuclear fuel while ensuring safety conditions in operating and emergency modes of nuclear power plants. Based on the developed method, the boundaries of the optimization area for upgrades of the thermal resistance of the fuel rod matrix thermal conductivity are determined in accordance with the accepted optimization criteria and safety conditions. It is established that when optimizing upgrades to the thermal resistance of nuclear fuel, it is necessary to take into account both normal operating conditions and emergency conditions with impaired heat removal from the reactor core. It is established that the optimal values of thermal resistance of nuclear fuel thermal conductivity depend on the design and technical parameters of reactor installations, composition, and condition of nuclear fuel, accident management systems, and other factors.

Purpose. The increase in energy costs and the need for further energy saving lead to an increase in requirements for reducing losses in the magnetic cores of transformers and reactors. Problem. The improvement of transformer and reactor equipment is traditionally carried out by applying the achievements of electrical materials science and new technologies to traditional designs and structures of electromagnetic systems. The basis of modern transformers is made up of laminated and twisted magnetic cores. The disadvantage of laminated magnetic cores is large additional losses in corner zones due to the texture of anisotropic steel. Disadvantage of twisted three-phase three-contour magnetic cores is large additional losses caused by the lack of magnetic coupling of three separate magnetic flux contours. The disadvantages of combined joint tape-plate magnetic cores are the unsatisfactory use of the active volume and increased losses, which are determined by the uneven distribution of the magnetic field and the negative impact of steel texture in the corner zones of the twisted parts. Aim. To determine the possibility of improving three-phase transformers and reactors. Methodology. The improvement is achieved by geometrical and structural transformations of the outer contours and elements of the varieties of magnetic cores. Results. The possibility of eliminating additional losses of a planar laminated magnetic core by a combination of anisotropic and isotropic steels at the appropriate location in the yoke-rod and corner sections is determined. With an octagonal outer contour of the combined magnetic core, a reduction in mass is achieved without an increase in losses. The mutually orthogonal position of the steel layers or the elements of the joint twisted and combined three-phase planar and spatial magnetic cores achieves magnetic coupling and elimination of additional losses of individual twisted contour sections. The hexagonal configurations of the inner contours of the twisted yoke-corner parts and the cross-sections of the laminated rods of the variants of the axial spatial joint magnetic core improve the magnetic flux density distribution and reduce the main losses of the yokes, as well as reduce the complexity of manufacturing rods from identical rectangular steel layers. Originality. The paper presents constructive and technological proposals and features of varieties of non-traditional planar and spatial, laminated, twisted and combined tape-plate joint magnetic cores, which differ in the combination of anisotropic, isotropic and amorphous steels, as well as the multifaceted geometric shape of contours and the spatial arrangement of elements. Based on the identity of the optimal geometric ratios of the variants of electromagnetic systems of transformers and reactors, with joint planar and spatial twisted and combined and tape-plate magnetic cores, the unification of the structure of transformer and reactor equipment with a capacity of I-III dimensions.

The paper is devoted to the analytical inspection and parameterization of the dynamics of the world’s nuclear energy complex from the first selfsustaining chain reaction to the present day. The rapid development of nuclear power in the 1970s and 1980s slowed down significantly at the beginning of the third millennium. The dynamics of increasing operational capacities is a linear unfolding of the completed turn of the spiral of development. Almost 90 % of electricity in the nuclear power industry in 1970–2021 was generated by PWR and BWR light water reactors. It is expected that their technological resources will be exhausted by 99 % by 2077. If the current pace of development is maintained, the share of electricity generated by NPPs in the world by that time will decrease to 1,5 %. Nuclear power capacities in Europe and America are declining, while is developing in Asia, particularly in China, where almost 70 % of the nuclear power plants under construction are located. The rate of decline in uranium production indicates to by 2040 no more than half of the world’s nuclear fuel demand will be met. Safety and security of the nuclear energy complex are considerably decreasing with the growth of reactor capacity, and the discrepancy between the calculated and observed probabilities of a severe radiation accident reaches two orders of magnitude. As a result of current manifestation of great-power nuclear terrorism, the global nuclear safety and security system needs to be overhauled. Further development of the nuclear energy requires a “technological leap”. At present, there is no technology available for widespread implementation that could increase nuclear reactor capacity by an order of magnitude without compromising nuclear safety, especially considering that fusion reactor technology is unlikely to be widely implemented in the next few decades. A technological bridge between existing and future developments could serve small modular reactors which in the short term could mitigate the energy supply shortage.

In this paper, a new method for measuring the neutron flux using proportional counters SNM-18 filled with 3Ne is studied. When developing equipment for automated measurement of the neutron flux of the research reactor VVR-K, the determining optimization criteria are power consumption, weight and dimensions. For this purpose, devices were used for automated measurement of the equivalent of soil moisture and the equivalent of snow water by the neutron component of cosmic rays. A number of experimental studies have been carried out to determine the optimal levels of supply voltages, the design of the device for operation at the VVR-K reactor has been changed. The main elements of the neutron detector design are a block of a hydrogen-containing moderator; a tube of a proportional thermal neutron counter; an amplifier and a microcontroller for analyzing the signal from the detector; a high-voltage power supply and a transmitter. Special software has also been developed for simultaneous control of detectors. Test measurements of the neutron flux were performed at the research reactor plant VVR-K INP using a Pu-Be neutron source, with an intensity of 1.8 *106 n/s. To reduce the neutron intensity for the safety of personnel and to reduce the load on the detector, the neutron source was placed inside a boron polyethylene collimator. [ABSTRACT FROM AUTHOR]

China’s nuclear energy ambitions, backed by the strong financial potential of the national economy, and the consequent desire to extend its successes in international economic cooperation to the nuclear industry have attracted the researchers’ attention to a closer examination of the current state and nuclear industry prospects of China, taking into account its technological component. The unfulfilled development plan for nuclear power in the 13th Five-Year Plan, as a result of systemic mistakes and failures in the projects selected for implementation, leads to the conclusion that it is necessary to involve foreign leaders in this field, including “Rosatom” corporation, which has in its portfolio virtually verified modern technical solutions.

To develop the latest energy-saving technologies, it is necessary to use effective and affordable thermal insulation materials. For a long time, and most importantly with great success, materials made from rock melts – basalts – have been used abroad. Basalt is the most acceptable raw material for producing environmentally friendly and most importantly inexpensive products. In Russia, there is an increasing interest in products based on basalt fiber, due to the rapid development of construction. At the moment, more than 300 deposits of basalt rocks have been discovered on the territory of Russia. And in the strategy of socio-economic development of the North Caucasus Federal district until 2025, the production of building materials from basalt is designated as a priority industry. However, there are also a number of problems that hinder the development of production capacities for processing igneous rocks into continuous basalt fiber, such as maintaining a constant temperature.

The relevance the research is caused by the need to ensure uniform heating of the acid solution at the injection rates created by the units onto the thermoacid samples. A solution to this problem will improve the efficiency of acid and thermal acid treatments of highly drained wells with low reservoir pressure. The main aim of the research is to develop and propose a method of acid and thermoacid impulse, a methodology for its application and to create structures for underground and surface equipment of wells for implementation of the developed method. Objects. The volume of the solution poured into the tubing during thermo-acid treatment by the pulsing method depends on their length and inner diameter. Usually it is taken equal to 1,2–2 m3. If the filter or some its part turned out to be blocked with a sand plug in the well, scheduled for thermal acid treatment by the pulsing method, then they were preliminarily cleaned with a thief without opening the sump. A special perforated tip and a special filling head are used as well. Methods. Thermal acid (as well as acidic) treatment of a well by the pulsing method is carried out without the use of a pump unit, which can significantly reduce costs. Accelerating the movement of the acid solution, heating the entire volume to the desired temperature and creating pressure (due to the weight of the solution column) contribute to an increase in the depth of penetration and the effectiveness of the action of the acid on the formation. Results. The most suitable acid solution for thermoacid impulse is 15 % HCl, inhibited by unicol. Good results were obtained by introduction of the acid impulse method, which involves the use of a special tip, in which the nozzle channel is completely closed with a magnesium rod. As a result of the reaction, the magnesium rod dissolves in the acid solution, after which the latter rushes through the vacated choke channel and the perforated pipe into the filter, creating the so-called acid pulse, i. e. increase in the injection rate is achieved under the action of hydrostatic pressure.

The paper presents the results of reactor tests of fuel assemblies with cladding made of zirconium alloy grade СTZ-110 at the material testing reactor of National Research Center (NRC) "Kurchatov Institute" at Novovoronezh and Leningrad NPP under various nuclear fuel burnups. It was shown that after all test cycles, the parts from zirconium in the fuel assemblies were in good condition, which was confirmed by metal research of the samples cut out from the fuel elements. The mechanical properties of the fuel cladding made of СTZ-110 alloy are stable and satisfactory. Maximum burn-outs were achieved in the VVER-1000 mode of 67.4 MW·day/kg of uranium and the RBMK-1000 mode – 76.0 MW·day/kg of uranium.

Introduction. The article substantiates the need for high-temperature processing of feed ingredients. Principles of operation and design features of the applied methods and equipment for feed production are considered. Phase transitions, along with advantages and energy, technological, and technical drawbacks are highlighted. The aim of the study is to justify a possibility of creating high-efficiency production lines using heat treatment of feeds by application of heat valves ensuring continuous loading of raw materials into a reactor and discharge of the treated feed at high pressures and temperatures. Materials and Methods. It is proposed to transfer the process of barothermal processing to a higher zone of the phase diagram of the system p,t (pressure and temperature). This is a section of the superheated steam zone with temperature 300–374 °C, pressure 12–21 MPa and treatment exposure 30–60 seconds, which replaces costly processes of normalizing, expansion, extrusion and granulation. The change in enthalpy in the pressure range 0–21 MPa and temperature range 0–600 °C is shown. Thermal modes are presented as formulas which is the basic condition for the use of digital technologies. Results. The design of the reactor with a thermal gate for loading and unloading, being the main unit of the production line of the feed heat treatment, was proposed. The results of the study are fundamental for the development of the sample flow low-capacity line. Discussion and Conclusion. The transfer of the process of barothermic processing of feed into the zone of superheated steam allows for the transfer of poorly digestible elements of grain and legumes in easily digestible, pathogen-free feed. Advantages of the reactor and line include the user-friendly design, energy saving and possibility of implementation of advanced digital technologies.

The effect of the rotation number of the propeller mixer on the concentration of sulfoxide sulfur in the oil fraction of Arlan oil during the oxidation of this fraction sulfides with hydrogen peroxide along with an acid catalyst, a mixture of formic and sulfuric acids in a mixing reactor, was studied. The dependences of the concentration of sulfoxide sulfur in the oil fraction and the reaction rate of the oxidation of the fraction sulfides to sulfoxides are obtained experimentally depending on the intensity of heterogeneous blend mixing in the blending reactor.

In the article the questions of optimization of technological parameters of mutual functioning of the system of apparatuses of the reactor block of semi-coking of slate with a solid heating agent (UTT) are considered.

The article presents results of research (thermal-hydraulic analysis) of initiating events (regulatory regimes), associated with the uncontrolled movement and ejection of control rods that had previously not been considered quantitatively in the evaluation of thermal shock and cyclic strength of the reactor vessel and internals. The purpose of the research is preliminary evaluation of the influence selected regimes to the reactor components, preparation of boundary conditions for further strength analysis, based on which will make the final conclusion about the impact of these regimes. Research has a scientific and practical significance, because neglect of these conditions can lead to a distortion of the calculations results on the basis of which a decision on the possibility of extending the service life of VVER-1000 was made. The research was conducted by performing a computational analysis using code RELAP5/Mod3.2. In accordance to IAEA recommendations in this case conservative approach is applied to the selection of initial and boundary conditions. Calculation analysis showed that the considered initial events are representative and should be considered in VVER-1000 life extension, but strength analysis is required for confirmation

The results of experimental studies of local hydrodynamics and mass exchange of coolant flow behind spacer and mixing grids of different structural versions that were developed for fuel assemblies of domestic and foreign nuclear reactors are presented in the article. In order to carry out the study the models of the following fuel assemblies have been fabricated: FA for VVER and VBER, FA-KVADRAT for PWR-reactor and FA for KLT-40C reactor. All the models have been fabricated with a full geometrical similarity with full-scale fuel assemblies. The study was carried out by simulating the flow of coolant in a core by air on an aerodynamic test rig. In order to measure local hydrodynamic characteristics of coolant flow five-channel Pitot probes were used that enable to measure the velocity vector in a point by its three components. The tracerpropane method was used for studying mass transfer processes. Flow hydrodynamics was studied by measuring cross-section velocities of coolant flow and coolant rates according to the model cells. The investigation of mass exchange processes consisted of a study of concentration distribution for tracer in experimental model, in determination of attenuation lengths of mass transfer processes behind mixing grids, in calculating of inter-cellar mass exchange coefficient. The database on coolant flow in fuel assemblies for different types of reactors had been accumulated that formed the basis of the engineering substantiation of reactor cores designs. The recommendations on choice of optimal versions of mixing grids have been taken into consideration by implementers of the JSC “OKBM Afrikantov” when creating commissioned fuel assemblies. The results of the study are used for verification of CFD-codes and CFD programs of detailed cell-by-cell calculation of reactor cores in order to decrease conservatism for substantiation of thermal-mechanical reliability.

На прикладі реактора без сталі типу РОМ-510/26 з електромагнітними екранами порівнянням результатів розрахунків проведена верифікація аналітичних і чисельних скінчено-елементних методів. Для уточненого аналітичного розрахунку горизонтальні і вертикальний екрани реактора для врахування їх кінцевих розмірів представлені системою короткозамкнених елементів. Виконується розрахунок їх індуктивностей, розподілу струмів і втрат в екранах, магнітного поля і втрат в обмотці, розрахунок нагріву обмотки емпіричним методом «перегрівів». Показано, що аналітичні розрахунки з достатньою точністю відповідають дослідженням чисельними методами електромагнітного і теплового CFD-аналізу. Апробовані і перевірені результатами вимірів методи рекомендовані для практичного застосування при промисловому проектуванні устаткування

The relevance of the research is caused by the need to increase energy efficiency when using hydrocarbons for combined production of chemical products and energy carriers applying gasification technologies. This will allow reducing production costs and expanding the possibilities of gas chemistry. The main aim of the research is to determine the thermodynamic efficiency of partial fuel oxidation reactors, being the part of energychemical plants, by the combined production of energy carriers and synthesis gas. The main attention is paid to the influence of the regime parameters on numerical value of the exergy efficiency. Object of the research is a partial oxidation reactor with a set of auxiliary equipment for providing synthesis gas production. This takes into account the system factor, i. e. parameters of the power system within the framework of which it is planned to build a similar type of power plant. Method: numerical experiment involving traditional approaches to compiling exergy balance of heat and power plants. The authors have used as well the mathematical models developed earlier by them for calculating the parameters of synthesis gas formed at processing hydrocarbon raw materials in flow-through autothermal non-catalytic reactors. Results. The obtained results enable us to choose the most expedient operating parameters of the partial oxidation reactor, which is a part of the energy-chemical plants with the gasification of unstable gas condensate. So the maximum values of exergy efficiency are achieved by using atmospheric air without enrichment with oxygen, both for the case of water vapor supply ( ŋ ex =78-83 %), and for the case without steam supply ( ŋ ex =82-88 %). At the same time, some variants of thermal schemes of energy-chemical plants with fuel gasification in thermodynamic terms can be considered equally effective, and the decision on the amount of water vapor supplied to the reaction zone must meet the requirements for synthesis gas. The choice of working pressure level in the reactor requires additional studies since the evidence of the use of the atmospheric-type reactor is not revealed at this stage of the study.

Project of a segmented antineutrino detector is developed with the use of plastic scintillator rectangular bars 10 x 10 x 100 cm, wrapped in Gd foils and assembled into an array of 1 m3 active volume. The scintillation array is sandwiched at both sides by the continuous light guides of 100 x 100 x 10 cm size, from which the scintillation light is spreading simultaneously through continuous light guides between all photomultipliers, forming the specific Light Response Function (LRF), which is character to a certain nuclear event in detector. Analysis of LRF allows one to effectively reject background events, providing high efficiency detection of antineutrino capture in the detector. Monte Carlo simulations with the help of MCNP and ZEMAX software show that with the use of selection criteria the neutrino events are well separated from the background.

The relevance of the discussed issue is caused by the need to optimize the geometry of the plasma-chemical reactor to increase the isotope effects. The main aim of the study is the search for the optimal geometry of plasma-chemical reactor, which provides high-localization of the plasma flow in the axial region for increasing isotope effects by reducing the back diffusion effect, leading to equalization of isotope concentration. The methods used in the study: calculation and optimization of the gas flow within the plasma-chemical reactor by the unsteady Navier? Stokes equations and Fourier by the method of finite-difference components using ANSYS Fluent. The results. The authors explained the mechanism of isotopic concentration change in the products of plasma-chemical reactions due to the spin separation of carbon isotopes in a nonequilibrium low-temperature plasma in a magnetic field. An analysis of the processes occurring inside the plasma-chemical reactor of constant width was carried out. It is expected that the reduction of isotope effects is associated with the oxidation of the dispersed phase, which is located on the reactor walls. A method and apparatus for limiting the contact area of the high-temperature plasma flow with the walls of the chamber was proposed. Calculation of gas flows inside the plasma-chemical reactor of the selected geometry was carried out. It is shown that for the contraction of high temperature gas flow in the central region and isolating it from the walls of the plasma reactor can be used thin diaphragm of temperature-resistant material. It was also shown that the wall temperature of the plasma-chemical reactor in the region between the diaphragms does not exceed the evaporation temperature of the dispersed phase in some plasma gas flow. The highest possible isotope effect which occurs in the processes of plasma in a magnetic field is largely retained.

The paper describes the semantic content of sound names in modern English. The list of sound names includes oneword lexemes and phrasemes. The respective terms suggested by the author are phononyms and phonophrasemes. The whole word-stock representing the sound universe makes up the world sound image (WSI). Nouns, adjectives, verbs and adverbs participate in the process of WSI formation. According to our way of thinking, phononyms are to be studied within the special subject of‘phononymy’ that must be part and parcel of lexicology.Besides, the paper investigates the linguistic particulars of sound genesis because it (sound production) actually offers a special mode of sound naming. The other mode of sound naming is offered by the notions of sound perception. To meet the needs of description, the author has introduced a number of new terms such as ‘phononym’, ‘phononymy’, ‘acoustive’, ‘actor’, ‘reactor’, etc.

Factory testing of a created high-voltage complex (plant) has been conducted. The complex consists of two pulse generators with the repetition rate of up to 50,000 pulses per second and load reactors with pulsed discharges - corona and barrier ones. Transistor (IGBT) keys are used as energy switches. The efficient mode of coke gas methane conversion (steam reforming) to syngas has been obtained with application of the complex created. A unidirectional action of the pulsed discharges, the gas mixture temperature, and a nickel catalyst has reduced the specific energy consumption for synthesis gas regeneration during the conversion. A feasible mechanism of this conversion is described.

During the prolongation of the terms of the nuclear power plants operation the main issue is the substantiation of the possibility of the terms of the reactor vessel operation, which determines the economic necessity to con-tinue operating the unit as a whole. Significant effect on the residual life of the reactor pressure vessel is to com-mit thermal loads, including thermal shock in case of the accident with leaky reactor circuit. The dimensionless method is developed concerning the rating conditions of the thermal shock to reactor vessels. Moreover, the at-tention is focused not on the known correlation approaches, but on the additional criteria, related to the com-pleteness of the heat transfer and terms strength of metal under thermal loading. Proposed methods can be the basic for the rapid diagnosis of the conditions of thermal shock to reactor in the accidents with leaky reactor cir-cuit.

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Copyright of Technical Electrodynamics / Tekhnichna Elektrodynamika is the property of National Academy of Sciences of Ukraine, Institute of Electrodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The analysis on accumulation of the spent nuclear fuel in Russia is carried out, variants of the management with the spent fuel of various types of reactors are presented, such prospect on long storage of the spent nuclear fuel, as dry storage is considered.

Neutrons interaction with matter under high density interactions (DI) was considered. It was shown that un-der neutron cross section measurement with high DI and production as result of interaction neutrons with matter of the second states with great value of such parameters as neutrons cross section, yield and life time probabil-ity of the interaction neutron with matter depends on DI and considered parameters. The expressions, related neutrons transmission, cross section and change of the neutrons transmission through the samples pair from different matters, which simultaneously placed on neutron beam, under the change of neutrons transmission sequence through them (transmission asymmetry) with DI and considered parameters of the second states were obtained. Method for revelation for the cross section change under DI change and improved experimental in-stallation were described.

Проведено аналіз існуючих пристроїв обмеження однофазних струмів короткого замикання. Розглянуто розроблений пристрій обмеження однофазного струму короткого замикання в нейтралі високовольтної обмотки автотрансформатора.

Possibility of determination of carbon resonance parameter from the set of experimental averaged cross sections, obtained using modified filters, is analyzed, results of computed simulation of such filters on basis of up-to-date evaluated nuclear data file libraries are presented, comparison of calculated and experimental filter parameters is realized, as well as estimation of the necessary experimental accuracy for measurements of the averaged cross sections for resonance parameters determination is fulfilled.

Project of a segmented antineutrino detector is developed with the use of plastic scintillator rectangular bars 10 x 10 x 100 cm, wrapped in Gd foils and assembled to an array of 1 m3 active volume. The scintillation array is sandwiched at both sides by the continuous light guides of 100 x 100 x 10 cm size, from which the scintillation light is spreading simultaneously through continuous light guides between all photomultipliers, forming the specific Light Response Function (LRF), which is character to a certain nuclear event in detector. Analysis of LRF allows one effectively reject background events, providing high efficiency detection of antineutrino capture in the detector. Monte Carlo simulations with the help of MCNP and ZEMAX software show that with the use of selection criteria the neutrino events are well separated from the background. [ABSTRACT FROM AUTHOR]

The technology for continuous production of silicon granules from monosilane through the liquid phase in an apparatus is based on a great variety of interrelated physical processes. A complex mathematical and full-scale modeling of equipment and processes of production and condensation of silicon vapors on a hot wall from various materials with the skull formation, liquid silicon flow, obtaining silicon droplets, their cooling, was made. As a result of the conducted studies, it was shown that any scientific technical constraints on the practical implementation of the technology of continuous granular silicon production in a plasma pyrolysis apparatus are absent. The adequate mathematical description of the process and equipment with different degrees of accuracy that allows implementing the engineering development of the pilot plant productivity of 100 kg/h was obtained. The discovered phenomenon of rapid collapse of the liquid silicon film into droplets allows creating a granulator on this basis. Thus, the conditions actually in one process operation of combining two processes - condensation of silicon vapor to liquid and production of granules are provided. [ABSTRACT FROM AUTHOR]

During the prolongation of the terms of the nuclear power plants operation the main issue is the substantiation of the possibility of the terms of the reactor vessel operation, which determines the economic necessity to continue operating the unit as a whole. Significant effect on the residual life of the reactor pressure vessel is to commit thermal loads, including thermal shock in case of the accident with leaky reactor circuit. The dimensionless method is developed concerning the rating conditions of the thermal shock to reactor vessels. Moreover, the attention is focused not on the known correlation approaches, but on the additional criteria, related to the completeness of the heat transfer and terms strength of metal under thermal loading. Proposed methods can be the basic for the rapid diagnosis of the conditions of thermal shock to reactor in the accidents with leaky reactor circuit. [ABSTRACT FROM AUTHOR]

The corrosion-electrochemical behavior of welded joints of steels and alloys, used as instrumental for organic synthesis processes in the presence of ozone was investigated. It was determined that welded joints in ozonated media are characterized by the increase in anodic current densities in the whole range of potentials and the shift of Ecor more negatively compared with the base metal that is associated with the decrease in active centers, on which ozone can be reduced. In ozone synthesis conditions, the alloy 06XH28HπT can be recommended as a structural material for reactors manufacture. In the ozone oxidation processes, it is necessary to pay attention to welded joints, especially for stainless steels such as "18-10" as wide "cathodic loop" formation on polarization curves indicates their tendency to intergranular corrosion (IGC). Corrosion can also proceed in dangerous areas of pitting formation and repassivation of steels under the ozone action. Welded joints of ferritic stainless steels 08X17T show the tendency to IGC in periodical ozone syntheses that precludes the possibility of using welding sets or requires protection of joint. [ABSTRACT FROM AUTHOR]

Neutrons interaction with matter under high density interactions (DI) was considered. It was shown that under neutron cross section measurement with high DI and production as result of interaction neutrons with matter of the second states with great value of such parameters as neutrons cross section, yield and life time probability of the interaction neutron with matter depends on DI and considered parameters. The expressions, related neutrons transmission, cross section and change of the neutrons transmission through the samples pair from different matters, which simultaneously placed on neutron beam, under the change of neutrons transmission sequence through them (transmission asymmetry) with DI and considered parameters of the second states were obtained. Method for revelation for the cross section change under DI change and improved experimental installation were described. [ABSTRACT FROM AUTHOR]