REACTOR MATERIALS-MODERN STATUS

N.A. Azarenkov, I.M. Neklyudov, V.N. Voyevodin

Full Text :   (4800 kB, Eng.) 

Abstract
This paper presents short description of modern status of reactor materials for nuclear. The fast growing energy demand and concerns about climate changes require nuclear energy to play a role among other energy sources to satisfy future energy needs of mankind. Exactly core materials behaviour provides safe and economy exploitation of nuclear power plants. Metals and alloys used in nuclear service serve in very challenging environments involving high temperatures and stresses, as well as exposure to high irradiation doses. Problems of radiation resistance of materials for exploitation reactors and reactors of next generation are described.

KEY WORDS: nuclear energetic, radiation resistant materials, radiation defects, impurities, reactors on thermal neutrons, fast reactors.

ON NEW REPRESENTATIONS OF WELL-KNOWN PHYSICAL PHENOMENA

V.M. Kuklin

Full Text :   (1400 kB, Eng.) 

Abstract
New theoretical description of well-known physical phenomena are announced. 1. The description of wave interaction in plasma in terms of spontaneous and stimulated processes is discussed. Such a description is not only attractive from the methodological point of view, but also offers new possibilities for the understanding of physical processes related to the interaction of radiation with matter. Moreover, there exists an intimate relationship between spontaneous and stimulated processes that can simplify the calculation of nonlinear terms for systems with multi-wave interactions. 2. It is shown by the example of two-level system that generation of coherent radiation is realized in excess of the threshold, determined by the equality of the squared population inversion to the half of the total number of all possible states. 3. The spectrum of waves emitted by oscillator, trapped in an external potential well is analyzed. It is assumed that the eigenfrequency of the oscillator is much greater than the frequency of oscillations in the potential well. The effect of the recoil on the absorption and emission of the oscillator is discussed. Since the energy of the slow oscillations in well is equal to the recoil energy, the intensity of the absorption and emission lines at the eigenfrequency exceeds the intensity of other spectral lines. 4. The formation of gravity surface waves with abnormally high amplitude, that occurs only in initial stage of nonlinear regime of modulation instability in the ocean, is considered. 5. The intensive long-wave Langmuir oscillation in plasma has been generated by a high-current charged-particle beam and a maser radiation is unstable. It being known the field energy density often exceeds the thermal energy density of plasma. In this case the modulation instability of intensive oscillation results one plasma density cavity over a wavelength of the intensive oscillation. It is shown, that kinetic limitation mechanism of cavity deepening is the local capture of ions. It should be noted, the potential of cavity is quite low for capture of great part of electrons with considerable kinetic energy.

KEY WORDS: spontaneous and stimulated processes, multi-wave interactions, threshold of coherent radiation, emission by oscillator, trapped in an potential well, modulation instability.

POLYADIC SYSTEMS, REPRESENTATIONS AND QUANTUM GROUPS

S.A. Duplij

Full Text :   (4100 kB, Eng.) 

Abstract
A review of polyadic systems and their representations is given. The classification of general polyadic systems is done. The multiplace generalization of homomorphisms, preserving associativity, is presented. The multiplace representations and multiactions are defined, concrete examples of matrix representations for some ternary groups are given. The ternary algebras and Hopf algebras are defined, their properties are studied. At the end some ternary generalizations of quantum groups and the Yang-Baxter equation are presented.

KEY WORDS: n-ary group, Post theorem, commutativity, homomorphism, group action, Yang-Baxter equation

ON THEORY OF SPECTRUM OF HYDROGEN-LIKE ATOMS

Yu.M. Poluektov, V.N. Savchenko

Full Text :   (1030 kB, Eng.) 

Abstract
Simple model of hydrogen-like atoms is proposed. Model is based on consideration of electron core, which consists of electrons in complete shells, using Thomas-Fermi model. Outer-shell electron is described by wave function. The model has no fitting parameters. Calculations of Rydberg correction for high-excited states with zero angular momentum are done. Calculations of energy of single ionization of hydrogen-like atoms and comparison with experimental data are done. The developed model can be used for further research of interaction of Bose-Einstein condensate and electromagnetic field.

KEY WORDS: Rydberg correction, alkali metals, atomic spectrum, Thomas-Fermi theory, atomic Bose - Einstein condensate

ON PHYSICAL PARAMETERS OF THE DEMONSTRATION STELLARATOR-REACTOR OPERATING IN THE MODE OF SELF-SUPPORTED THERMONUCLEAR REACTION

V.A. Rudakov

Full Text :   (1400 kB, Eng.) 

Abstract
With the use of a one-dimensional spatial-temporal numerical code under conditions of ambipolarity of neoclassical transport fluxes the regimes of the self-supported DT-fusion reaction in a reactor-stellarator are calculated. Cases of heating both ion and electron plasma components are considered. It is shown that powers of heating of plasma of scale 25 MW can be sufficient for excitation in reactor of the steady-state self-supported burning. Technical and physical parameters of such reactor correspond to characteristics of a demonstration reactor.

KEY WORDS: reactor-stellarator, ambipolar electric field, neoclassics, transport fluxes, plasma heating, power balance.

DETERMINATION OF SENSITIVITY OF SEMICONDUCTOR DETECTORS OF GAMMA-RADIATION

A.A. Zakharchenko

Full Text :   (1700 kB, Eng.) 

Abstract
Properties of response functions of room temperature gamma-radiation detectors based on wide band-gap semiconductors are researched using Monte-Carlo method. It is shown that approximate formulas which connect detector sensitivity with absorbed energy of monochromatic radiation in the energy range between 0.06 and 3 MeV can be obtained for some kinds of semiconductors. We determined gamma-quantum energy regions and detector thicknesses where obtained approximate formulas are correct. Regions of maximum error of approximate formulas are also determined.

KEY WORDS: semiconductor detector, gamma-radiation, Monte-Carlo method, response function, sensitivity

DIRECT-ACTION ACCELERATOR BASED ON THE MAGNETRON GUN WITH A SECONDARY-EMISSION CATHODE AND ITS APPLICATIONS IN RADIO-TECHNOLOGIES

A.N. Dovbnya, V.V. Zakutin, N.G. Reshetnyak

Full Text :   (2200 kB, Eng.) 

Abstract
Studies have been made into the parameters of the electron beam produced by the accelerator with the secondary-emission cathode magnetron gun as the basis. The experiments were performed in the energy range between 80 and 150 keV with a specific beam power on the target from 5 to 20 J/cm², this permitting the use of the beam for irradiating material surfaces. Plane metal samples were subjected to irradiation, and the radiated structure of material surface was examined by metallography methods. Experiments were made to measure the accelerator beam size in both decreasing and increasing magnetic fields; the possibility of irradiating inner and outer of cylindrical surfaces was demonstrated.

KEY WORDS: accelerator, magnetron gun, secondary-emission cathode, electron beam, irradiation, cylindrical surface.

INTEGRATION OF COMPUTATIONAL METHODS IN SPECTROMETRY OF ELECTRON BEAMS

V.T. Lazurik, V.M. Lazurik, G.F. Popov, Yu.V. Rogov, G.E. Sarukhanian

Full Text :   (1030 kB, Eng.) 

Abstract
Investigations related with developments of computer simulation and computational methods for spectrometry of sources irradiation are actual for decision of wide class of scientific tasks into industrial radiation processing. Investigations of influence of electron beam spectrum characteristics on the spatial absorbed dose distributions formation into materials with various atomic numbers were performed. Simulation of spatial distributions of electrons absorbed dose in an irradiated targets was accomplished with the Monte Carlo method by the program ModeRTL. Analysis of numerical experiments results are discussed.

KEY WORDS: computational spectrometry, spectrum electrons, dose distribution, Monte Carlo method, software ModeRTL

STRATIFICATION OF THE POSITIVE COLUMN OF A DC DISCHARGE IN NITROGEN

V.A. Lisovskiy, V.A. Derevyanko, Е.P. Artushenko, V.D. Yegorenkov

Full Text :   (3500 kB, Eng.) 

Abstract
This paper studies the stratification conditions of the positive column of the dc glow discharge in nitrogen in tubes of various radii. In each discharge tube the striations are observed in closed regions with respect to current and applied voltage values within the limited range of gas pressure values. We revealed that the first striation (counted from the cathode end of the positive column) was clearer expressed and it possessed the maximum thickness. Striation length is weakly dependent on discharge current but it decreases with gas pressure growing. Again the striations with a large order number (counted from the cathode edge of the positive column) possess lesser thickness. We find out that positive column stratification obeys similarity laws well. The extinction curves and striation existence regions registered in different discharge tubes and plotted against the product of gas pressure and inter-electrode distance pL coincide. Reduced striation thickness d/R (striation thickness d divided by tube radius R) in different tubes also is in good agreement with each other when plotted against pR. We observe that the reduced striation thickness obeys the Goldstein-Wehner law d/R = C/(pR)m, the constants for nitrogen being C = 1.05 and m = 0.32.

KEY WORDS: direct current glow discharge, positive column, striations, nitrogen, low pressure.

EFFECT OF HIGH-PRESSURE-INDUCED STRUCTURAL RELAXATION ON EVOLUTION OF THE TEMPERATURE DEPENDENCE PSEUDOGAP HoBa₂Cu₃O_7-δSINGLE CRYSTALS

Z.F. Nazyrov, N.N. Zavgorodnya, R.V. Vovk, K.A. Kotvitskaya

Full Text :   (1100 kB, Eng.) 

Abstract
In present work the influence of high pressure on the conductivity in the basal plane of the oxygen underdoped HoBa₂Cu₃O_7-δsingle crystals is investigated. It is found that excess conductivity Δσ(Т) in the HoBa₂Cu₃O_7-δsingle crystals over a wide temperature range (Tс < Т < T*, where Tc is the critical temperature and T* represents the mean field temperature of the superconducting transition) obeys an exponential temperature dependence. The description of the excess conductivity with Δσ~(1-Т/Т*)exp(Δ*ab/T) can be interpreted in terms of mean field theory. The temperature dependence pseudogap is satisfactorily described within the framework of the BCS-BEC crossover.

KEY WORDS: excess conductivity, hydrostatic pressure, HoВaCuO single crystals, high-temperature superconductivity, crossover, pseudogap state.

THE BASIC SUMMARIES OF WORKING OUT OF RECIRCULATOR SALO MAGNETOOPTICAL SYSTEM

I.S. Guk, S.G. Kononenko, F.A. Peev, A.S. Tarasenko

Full Text :   (5200 kB, Eng.) 

Abstract
Effects of modelling moving an electron beam in the optimised magnetooptical structure recirculator SALO are in-process resulted. Modelling is spent with the account of agency of nonlinear components of a magnetic field of dipole magnets and quadrupole lenses with use of programs TRANSPORT and MAD-X. The gained effects testify to a possibility of a beam production of the given sizes in points of a leading-out and beam acceleration without essential losses along accelerator.

KEY WORDS: electron, recirculator, dipole magnet, quadrupole lens, SALO

SOLID AND LIQUID WASTE PROCESSING AND REDUCING OF PERSONNEL DOSES

N.A. Azarenkov, V.G. Rudychev, S.A. Pismenetskiy, Y.V. Rudychev, P.S. Badzym, S.I. Shapar, O.V. Vystavna

Full Text :   (1600 kB, Eng.) 

Abstract
In order to minimize the radioactive waste volume at the Ukrainian NPP (nuclear power plants) solid waste is burned and compressed and liquid one evaporated. This dramatically increases their activity as well as their radiation doses during of operation process. In accordance with the ALARA principle the technological solutions that reduce doses to personnel were proposed. First part of the complex built on Zaporozhye NPP consists of processing waste incinerators and pressing facilities. The characteristics of the radiation fields for varying geometries of this facility and isotopic composition of obtained waste was simulated using PENELOPE and GEANT codes. Part of the results was performed using the software packages developed by the authors using point sources method. During operations with burned waste pressed ash the wall thickness of buildings, where equipment is placed is needed, up to 40 cm of concrete. Thickness of the steel technological doors for these premises is required to be of about 12 cm. The alternate design of technological doors (≈ 2cm of steel) by adding special gateway system is to be proposed.

KEY WORDS: radioactive waste, burned radioactive waste, pressed radioactive waste, liquid radioactive waste, radiation doses.

NUCLEAR GAMMA-RESONANCE OBSERVATION IN CONDITIONS OF COMBINED LINEAR AND TRANSVERSE DOPPLER SHIFTS AND FEATURES OF RELATIVISTIC THEORY

V.G. Kirichenko, О.V. Коvalenko, Т.А. Кovalenko, Yu.I. Gofman

Full Text :   (1200 kB, Eng.) 

Abstract
We consider briefly the problem of nuclear gamma-resonance observation and the effects of displacement energy gamma rays in conditions of combined linear and quadratic Doppler effect. The main result of this experiment was concluded in the possibility of realization of second order Doppler shift observation in the range of the combined shits with help of commutation electronic schemes for coherent transverse and linear shifts. This gives simplifications in experimental procedure. We reached the values of minimum measurable linear velocity of about 10^-5 mm/s·pulse using the isotope Sn¹¹⁹. It confirms the real possibilities of measurement method Doppler shift using the Mossbauer effect to determine the maximum acceleration and the prospects for development of such researchers.

KEY WORDS: Nuclear gamma resonance, linear and quadratic Doppler effect, the scheme of registration, the shift of the spectrum

FORMATION OF ASSOCIATES FROM NANOSIZED COMPLEXES OF URANIUM IN THE WATER - SUPERCRITICAL CARBON DIOXIDE SYSTEM

B.V. Borts, S.F. Skoromnaya, V.I. Tkachenko

Full Text :   (1800 kB, Eng.) 

Abstract
The paper describes the results from studies into the role of water in the formation of associates from nanosized complexes of uranium in a supercritical carbon dioxide (SC CO₂) medium. It has been demonstrated experimentally that water in the SC CO₂ exists in the form of microdrops. It is found that at a pressure of 10 MPa and a temperature of 40°C the UO₂(NO₃)₂⋅2 (C₄H₉O)₃PO complex may take on hydrophilic properties. The conclusion is made that in that event the mentioned complex would concentrate in water microdrops. The concentration of the complex in water microdrops gives rise to the formation of associates, the size of which is determined by microdrop dimensions.

KEY WORDS: supercritical carbon dioxide, supercritical fluid extraction, uranium, water, tributyl phosphate

ONCE AGAIN ABOUT ADVANTAGES OF THE NEW METHOD OF ELECTROMAGNETIC ISOTOPES SEPARATION

Yu.A. Kirochkin, A.Yu. Kirochkin

Full Text :   (650 kB, Eng.) 

Abstract
The advantage of the new method of electromagnetic isotopes separation in the crossed electric and magnetic fields in comparison with an ordinary method with the presence of only magnetic field is shown in the paper. It is also shown that the theory of ordinary method of isotopes separation in the magnetic field of linear current, written in article of Bardakov V.M. etc. in ZTF, 2010, Vol. 80, No. 10, pp. 115-119, is built wrong.

KEY WORDS: electromagnetic field, isotope, separation, current, trajectory

HIGH-SPEED COMMUNICATION NETWORKS CHAOTIC BEHAVIOR ANALYSIS OF DATA SYSTEMS

A.V. Karpukhin, I.N. Kudryavtsev, A.V. Borisov, D.I. Gritsiv

Full Text :   (1600 kB, Eng.) 

Abstract
Chaos and self-similarity are the state-of-the-art problems in various areas of modern science and technology, thus network systems are not exception from this rule. Increasing number of various network protocols, applications and services leads to the fact that network traffic becomes more complex and unpredictable. It has been shown that phenomenon of self-similarity is caused by the properties of network traffic whose origin is the behavior of ТСР protocol. And all this properties became more significant with appearing of the high-speed data transmission technologies. Finally this behavior leads to congestion in network and packet losses as the result of it. But even modern congestion control mechanisms handle such kind of situations quite unfair. For example, as shown by W. Feng et al., TCP Reno loss rate exceeds 5% in a heavily congested network. So it's easy to calculate that over a Gigabit Ethernet link such loss rate translates into a loss of over 50 Mb/s. Obviously this level of loss rate is unacceptable. However models that describe behavior of information systems sufficiently and give a possibility for scientists to apply all set of classical methods of chaos theory and analyze particular nonlinear dynamical system have not been offered so far. Phase portraits of the studied system were built and Lyapunov exponents for different values of the basic system parameters were calculated. In the present paper a new approach in analysis of the packet switching networks behavior with ТСР protocol is proposed. These networks are analyzed as nonlinear dynamical systems that show chaotic properties at a certain value of parameters.

KEY WORDS: self-similarity, network traffic, chaos, packet loss, quality of service, TCP/IP

ON EFFICIENCY OF COLLISIONAL ENERGY EXCHANGE OF ELECTRONS AND IONS IN RELATIVISTIC PLASMAS

I. Marushchenko, N.A. Azarenkov

Full Text :   (1400 kB, Eng.) 

Abstract
The collisional coupling of the relativistic electrons and non-relativistic ions in hot plasmas has been analyzed. It was shown that the relativistic effects produce a quite new feature in the collisional transfer of energy from the electrons to ions with different temperatures. While in the non-relativistic limit the condition for absence of the collisional decoupling is T_e/T_i < 3, the relativistic effects shift the maximum of the energy-exchange with increasing the temperature to a higher values of T_e/T_i until it finally disappears that makes an appearance of the collisional decoupling impossible.

KEY WORDS: relativistic plasma, kinetics, collisional energy exchange, collisional decoupling