CURRENT PROBLEMS OF NUCLEAR POWER: III AND III+ GENERATIONS ADVANCED REACTORS

D.P. Belozorov and L.N. Davydov

Full Text :    (2500 kB, Rus.)

Abstract
Basic tendencies in development of nuclear power industry at the beginning of 21 century are demonstrated with advanced nuclear reactors of the third-generation. After definition of generations of industrial nuclear reactors the principal designs of the second-generation reactors now in operation are briefly considered. The present concepts and designs of the third- generation reactors are considered in details - both of high (above 300MWte) and of low powers. These reactors being an evolutionary development of the proceeding generation satisfy a number of severe requirements and are much more cost-effective. Their most significant distinction from the second-generation reactors is in elements of passive or inherent safety. In the case of plant failure to prevent an accident these mechanisms do not require active intervention of in-plant personnel but rely on physical principles of gravity, natural convection and sufficient heat-resistance of construction elements. Various types of the third-generation reactors are mentioned in the review - they are water-cooled, gas-cooled, liquid metal-cooled and molten salt reactors with water and graphite moderators and different fuel elements: rod-like, spherical and prismatic. The reactor core can be of modular, integral, vessel- or pool- type designs etc. Russia is one of the countries leading in nuclear reactor industry. Nuclear power plants of Russian designs operate on the territory of Ukraine. That is why the third- generation reactors developed and designed in this country are considered in more detail. One of the purposes of the review lies in the attempt to estimate what advances in nuclear reactor industry can be essential in our country and what are the goals of Ukraine in its future nuclear-power program. The review connects short analysis of the current state of Ukrainian nuclear power industry and the objectives of its development in the 21st century taking into consideration "The Power Strategy of Ukraine" and the corresponding scenarios of the development of its nuclear power industry up to 2030.

KEY WORDS: nuclear reactor, nuclear energy, PWR, fast reactor, gas reactor, coolant, reactor capacity, burn-out.

ANALYSIS OF CHARGE FORM FACTORS OF THE ⁶LI NUCLEUS ON THE BASIS OF CLUSTER MODE

Yu.A. Berezhnoy, V.V. Pilipenko

Full Text :    (470 kB, Rus.)

Abstract
Several variants of the phenomenological cluster model of the ⁶Li nucleus - namely, the a+d model of nucleon associations and the cluster model with dispersion for the a+d and a+p+n systems - have been considered to be applied to description of the elastic charge form factor of the ⁶Li nucleus and of the form factor of inelastic scattering with excitation of the first 3⁺ state in the target nucleus. The values of the model parameters have been determined from the analysis of experimentally measured form factors. It has been shown that the cluster models under consideration provide a good description of both elastic and inelastic form factors but the cluster model with dispersion looks to be most preferable.

KEY WORDS: the ⁶Li nucleus, cluster model, charge form factor, inelastic form factor, root-mean-square radius, dispersion parameter.

THE INFLUENCE OF IMPULSE LASER IRRADIATION ON STRUCTURE OF SURFACE LAYS ZIRCONIUM ALLOY

V.G. Kirichenko, A.I. Kirdin, T.A. Kovalenko, A.V. Ostapov

Full Text :    (2600 kB, Rus.)

Abstract
The considerable change of surface structure and phase composition of ferriferous zirconium alloys under irradiation by AYG: Nd³⁺ laser with 50 ns impulse duration and energy up to 5 Joule per impulse were discovered. The surface structure change was detected as step-wave formations and strain relaxation in the areas of intermetallic phase inclusions. The phase composition change was caused by different nature of motion for ferriferous zirconium alloys phase inclusions under laser irradiation. It was in direction from surface to deep for strained alloys and from deep to surface for annealed alloys.

KEY WORDS: zirconium alloys, impulse laser irradiation, surface, mircostructure evolution, phase transformations.

GENERAL RELATIVISTIC SPIN PRECESSION AS MANIFESTATION OF RYTOV-VLADIMIRSKY-BERRY GEOMETRICAL PHASE

Y.Y. Zanimonskiy , Yu.P. Stepanovsky

Full Text :    (250 kB, Rus.)

Abstract
Realization of great opportunities of modern accurate quantum measuring systems needs to perform the complex analysis of corresponding problems of theoretical physics. For quantum metrology it is important to investigate the spin movement of particles, in particular photons, moving in external fields. In the paper the notion of wave function for arbitrary spin massless particle is discussed. These wave functions satisfy some relativistic wave equations under consideration in the paper. The semiclassical motion of arbitrary spin massless particle in general relativity is considered. The evolution of particle polarization state is investigated by using the method of Rytov-Vladimirsky-Berry geometrical phase. A simple derivation is given for calculating of general relativistic spin precession of the particle. It is shown that Born-Fock-Simon condition is of great importance for general relativistic spin precession calculation.

KEY WORDS: massless particle, spin, helicity, precession, geometrical phase.

CALCULATION OF INDUCED ELECTRIC FIELD NEAR CONDUCTIVE STRUCTURES

V.N. Bolotov, R.A. Druzhchenko

Full Text :    (430 kB, Rus.)

Abstract
Distributions of induced electric fields near plane surface of finite size have been calculated, including fractal structures like Sierpinski carpet. Construction of the calculated scheme is based on the fact that connected conductive surface of arbitrary geometry is the equipotential surface. This enabled to compose and solve the system of algebraic equations for induced charges density and then to calculate electric fields at any point of the space. The calculations have been executed for different positions of external charge relatively conductive finite surfaces of different geometrics.

KEY WORDS: electrostatics, induced charge, fractal structures, induced electric fields.

STUDY OF THE SYNCHROTRON DYNAMICS IN COMPTON X-RAY RING

E.V. Bulyak, P.I. Gladkikh, V.V. Skomorokhov

Full Text :    (490 kB, Eng.)

Abstract
Within the bounds of a model of the electron storage ring that consist only of a drift and a radio-frequency cavity, the longitudinal dynamics of electron bunches with large energy spread is considered. Under consideration, the model of the storage ring with small momentum compaction factor is sufficiently nonlinear. The finite-difference equations and differential equations of motion in the canonical form are derived for this model. Based on the differential model, topology of the longitudinal phase space and its modifications due to changes in the ring parameters is considered. The analytical expression for the factor, which determined the topology of the longitudinal phase space, was derived. The response of equilibrium area upon changes of the nonlinear momentum compaction factor is presented. It is show that enlargement of the energy acceptance of the ring by decreasing of the momentum compaction factor is limited with the nonlinearity in the compaction factor. Decreasing of the linear compaction factor below the certain limit causes the reversed effect - decreasing of the acceptance. Comparative analysis of the finite-difference and differential models is made by means of computational simulations. The results of simulation manifest a good agreement with the theoretical predictions on the sizes and the positions of equilibrium areas.

KEY WORDS: electron storage rings, synchrotron nonlinear dynamics, Compton X-ray sources.

PECULIARITIES OF RADIATION FROM NEGATIVE CORONA DISCHARGE UNDER TRICHEL PULSE MODE IN AIR

L.М. Zavada, B.B. Каdоlin, О.V. Bоlоtоv, I.А. Pacshenko, S.G. Pugach, S.N. Man’kovsky

Full Text :    (310 kB, Rus.)

Abstract
Experimental results of space-time characteristics of negative corona discharge radiation in air under Trichel pulsed mode, are presented. It was shown, that negative corona discharge radiation concentrated near cathode and anode areas, and radiation intensity considerably depends on anode shape. Corona discharge radiation under Trichel pulsed mode has pulse character. At the same time the radiation pulse from the needle cathode area appears with current pulse simultaneously, but the radiation pulse from the anode area is formed with time delay to the beginning of the current pulse. The time duration between the beginning of the current pulse and the beginning of the radiation pulse, from the anode area, depends on applied voltage value and the distance between electrodes, however the amplitude relationship of radiation pulses depends on the applied voltage value only.

KEY WORDS: negative corona discharge, Trichel pulse, radiation, drift zone, anode area, perturbation wave, anode shape.

SIMULATION OF VOLTAGE-CURRENT CHARACTERISTIC OF X- AND GAMMA-RAY DETECTORS BASED ON Me-CdZnTe-Me STRUCTURE

D.V. Kutniy, V.E. Kutniy, A.V. Rybka, I.N. Shlyahov, A.A. Zakharchenko, K.V. Kutniy, A.A. Veryovkin

Full Text :    (340 kB, Rus.)

Abstract
The features of barrier contact forming on high-resistance semiconductor compound CdZnTe p-type for making detectors X- and γ-irradiations were reviewed. Efficiencies of gamma-irradiation registration in a wide power range by CdZnTe crystals of different thickness were estimated. The equivalent circuitry of a MSM structure is offered, allowing to simulate various types and variants of electrodes. On the basis of Au-CdZnTe-In structure was created detectors for detecting low-energy γ-irradiation, characterized by small leakage current 1,5 nA at a bias voltage 100 V.

KEY WORDS: CdZnTe, detector, γ-irradiation, voltage-current characteristic, contact, metal-semiconductor-metal structure.

DEPENDENCE OF THE ELECTRON BEAM LIFETIME IN NESTOR STORAGE RING ON RESIDUAL GAS PRESSURE

P.I. Gladkih, V.G. Grevtsev, A.Yu. Zelinsky, I.M. Karnaukhov, N.I. Mocheshnikov, A.O. Mitsikov

Full Text :    (290 kB, Rus.)

Abstract
The main mechanisms of accumulated particles losses, such as elastic and inelastic scattering by electrons and nuclei of residual gas atoms; intrabeam scattering (Toushcek effect), quantum life time in the electron storage ring NESTOR (N-100M) what construct in the NSC KIPT for generation of intensive X-Ray beam on the base of Compton scattering are considered. It is shown that the main losses of the accumulated beam in the area of low energies of the beam happen due to elastic particles scattering on nuclei, while in the field of high energies inelastic scattering effects prevail. Dependence of partial and total lifetimes on the energy of an electron beam is built. Vacuum chamber aperture and value of dynamic pressure are defined.

KEY WORDS: lifetime, electron beam, electron storage ring, vacuum chamber, residual gas.

THE USING OF PIXE AND PYROLYTIC GRAPHITE FILTER TO DETERMINE OF Fe IN ZrF₄

V.V. Levenets, O.P. Omelnyk, A.O. Shchur, A.E. Chernov

Full Text :    (310 kB, Rus.)

Abstract
In this paper the features of filter on base of pyrolytic graphite were explored to modify the proton induced X-rays spectrum. The parameters of X-rays emission passing function were founded for optimization of conditions of determination iron in zirconium tetrafluoride. Whereas 33 % of X-rays emission of Fe К_a passes through filter the coefficient of suppression of Zr К_a emission was estimated as n´10³. The limit of detection of iron in zirconium of n´10^-5 was reached. This circumstance makes it possible to use developed technique for the fluorine-zirconate glasses content exploration.

KEY WORDS: X-ray radiation, pyrolitic graphite, iron, zirconium, glasses, beam of proton, pixe.

INFLUENCE OF SEVERE PLASTIC DEFORMATION ON ELECTIC RESISTIVITY AND THERMAL E. M. F. OF ZIRCONIUM

V.M. Azhazha, A.N. Velikodny, M.A. Tikhonovsky, I.D. Tolmachev, V.G. Yarovoy

Full Text :    (450 kB, Rus.)

Abstract
The behavior of electrical resistivity and thermal e. m. f. of zirconium under cold drawing with high strains was studied. It was shown that thermal e. m. f. S and relative electrical resistivity r₂₉₃/r₇₇ decrease under deformation in a similar manner. Resistivity at 77 K increases under deformation in a monotonous way, whereas resistivity curve at 169 K and 293 K possess a plateau in the range of true strain values e » 2 ¸ 5,5 and even slight decreasing at e » 3. Possible reasons causing this behavior of resistivity are discussed.

KEY WORDS: severe plastic deformation, electrical resistivity, temperature coefficient of resistance, thermal e. m. f.

FORMATION OF MULTILAYERED COVERINGS TiN/Mo BY THE VACUUM - ARC METHOD WITH USE THE HFDISCHARGE

V.M. Beresnev, A.D. Pogrebnjak, O.M. Shvets, E.V. Fursova, N.N. Chernyshov, L.V. Malikov

Full Text :    (670 kB, Rus.)

Abstract
It is shown an opportunity of formation nanolayer, TiN/Mo coverings by the method of vacuum-arc sedimentation with use HF of the category for suppression of microparticles of a plasma stream. Coverings besieged from two sources. Laws of changes of structural - phase characteristics, microhardness Н_m coverings TiN/Мо received are established at various values of the accelerating potential of a substrate. Change of dependence Н_m, from potential of displacement with a maximum of values 32GPа were observed in the 200V is established. Tribotechnics characteristics of nanolayer coverings in comparison with covering TiN are investigated.

KEY WORDS: the HF discharge, nanolayer coverings, structure, microhardness, tribotechnics characteristics.

A FORMULA FOR K-SHELL IONIZATION CROSS SECTION OF Si ATOMS BY RELATIVISTIC ELECTRONS IN A THIN SILICON LAYER

A.V. Shchagin, V.V. Sotnikov

Full Text :    (250 kB, Rus.)

Abstract
The data on the cross section for K-shell relativistic-electron ionization of Si atoms in a thin silicon layer are analyzed in the paper. The available measured data and the calculations of cross sections by different formulas taken from the literature are presented. The influence of the density effect on the cross-section behavior at high energies of incident electrons is discussed. A simple formula is derived to approximate the available experimental data on silicon. The formula for calculating the cross section for K-shell ionization of Si may be used in the analysis of the experimental data on the yield of characteristic X-ray radiation from a thin silicon layer at incident electron energies from unities to hundreds of MeV. Application of characteristic X-ray radiation in experiments with high energy particles are discussed.

KEY WORDS: K-shell ionization cross section of atoms by electron impact, characteristic X-ray radiation, density effect.