No abstract

The luminescence of Kr-Xe, Ar-Kr, and Ar-Xe mixtures was studied in the spectral range 300–970 nm when excited by 6Li (n, α)3 H nuclear reaction products in the core of a nuclear reactor. Lithium was deposited on walls of experimental cell in the form of a capillary-porous structure, which made it possible to measure up to a temperature of 730 K. The temperature dependence of the radiation intensity of noble gas atoms, alkali metals, and heteronuclear ionic noble gas molecules was studied. Also, as in the case of single-component gases, the appearance of lithium lines and impurities of sodium and potassium is associated with vaporization during the release of nuclear reaction products from the lithium layer. The excitation of lithium atoms occurs mainly as a result of the Penning process of lithium atoms on noble gas atoms in the 1s states and subsequent ion-molecular reactions. Simultaneous radiation at transitions of atoms of noble gases and lithium, heteronuclear ion molecules of noble gases allows us to increase the efficiency of direct conversion of nuclear energy into light.

No abstract

Research results of luminescence spectra of noble gases and Ar–Xe, Ar–Kr, and Kr–Xe mixtures under the excitation by products of nuclear reaction in the core of a stationary nuclear reactor with 0.87 × 1014 n/cm2s thermal neutron flux are described in the article. The emission spectra of noble gases are similar to the obtained spectrum under the excitation by the 40Ar+7 ion beam from the DC-60 accelerator. Bands in spectra of the binary mixtures of noble gases are connected with the radiation on heteronuclear ion molecule transitions. The appearance of the lines of alkali metal atoms at the temperature increase of gas chamber is explained by sputtering of the lithium layer via nuclear reaction products as well as ionized and excited particles of the buffer gas.

The present paper examines the luminescence of ternary Ar-Kr-Xe and Ne-Ar-Kr mixtures of noble gases in the spectral range from 300 to 970 nm, excited by the 6Li(n,α)3H nuclear reaction products in the core of a nuclear reactor. A thin layer of lithium applied on the walls of the experimental device, stabilized in the matrix of the capillary-porous structure, serves as a source of gas excitation. During in-pile tests, conducted at the IVG.1M research reactor, thermal neutrons interact via the 6Li(n,α)3H reaction, and the emergent alpha particles with a kinetic energy of 2.05 MeV and tritium ions with a kinetic energy of 2.73 MeV excite gaseous medium. The study was carried out in a wide temperature range. The temperature dependence of the intensity of the emission of the atoms of noble gases and alkali metals, heteronuclear ionic molecules of noble gases were studied. The obtained values of the activation energy of the emission process 1.58 eV for lithium and 0.72 eV for potassium agree well with the known values of evaporation energy. Excitation of alkali metals atoms occurs consequently of the Penning process of alkali metals atoms on noble gas atoms in the 1s-states and further ion-molecular reactions.

At the present time the direct nuclear energy conversion into optical radiation is realized in gas media in which filling of energy levels takes place in the low-temperature plasma (nuclear-excited plasma) induced by ionizing radiation. The research of optical radiation of the nuclear-excited plasma induced by products of nuclear reactions is interest for development of an alternative outlet method of energy from the nuclear reactor, creation of control and regulating bodies for parameters of nuclear reactors as well as creation of one of diagnostics of high-temperature plasma in fusion reactors. The purpose of this work was to obtain new experimental data about processes of nuclear energy conversion into optical radiation with the optimal gas media having high coefficient of nuclear energy conversion into optical radiation and also with a possibility of outlet method of energy from the nuclear reactor core. In this article, description of the reactor experimental bench (LIANA) and the experiment scheme, the irradiating ampoule device (AD) with surface source of charged particles is provided, and the procedure of reactor experiment is presented. This paper presents the results of the reactor experiments of studying the spectral-luminescent characteristics of unary noble gases (Ne, Ar, Kr, Xe) and binary Kr-Xe gas mixture in a 200–975 nm spectral range with ionization gaseous media by products of 6Li(n,α)T nuclear reaction under irradiation at research water-cooled heterogeneous reactor (the IVG.1M).

No abstract

The behavior of structural materials of nuclear and fusion reactors during operation largely determines their safe and economical work. Structural materials of nuclear and fusion reactors are operating under conditions of interaction with various chemical active elements (gases, vapor-gas mixtures, fission products, etc.) in a wide temperature range; they are subject to high requirements in terms of their thermal and corrosion resistance. This paper presents the new methodology of complex studies on structural materials corrosion resistance of nuclear and fusion reactors with different gases and vapor-gas mixtures by thermal-gravimetric analysis (TGA), differential-scanning calorimetry (DSC) and mass spectrometry (MS) methods simultaneously.