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Experimental works performed on the Dubna gas-filled magnetic recoil separator (GFS) to study the reactions of formation of 294Ts and 294Og nuclides and the properties of their radioactive decay are described. Future possibilities of synthesizing new elements with Z = 119 and Z = 120 and performing experiments to study the properties of heavier isotopes of known superheavy nuclei Lv (Z = 116), Ts (Z = 117), and Og (Z = 118) are discussed.

A new series of experiments aimed at the synthesis and study of decay properties of the most neutron-deficient isotopes of element Fl (Z = 114) and of the heaviest isotopes of 118 element is planned at the DGFRS (FLNR JINR). An appropriate registering system is to be implemented to transfer spectrometric data from double-sided silicon strip detector (DSSD). New analog modules were designed that allow to simplify existing multi-channel measurement system and to improve the real-time method of “active correlations” in search for the rare events of SHE formation and decay. The main features of the new modules the 16-channel charge-sensitive preamplifier, the 16-channel analog multiplexer and the 1.25 MSPS 12-bit Parallel ADC are presented.

The possibilities of competitive development of a liquid-salt reactor with a cavity-type core for developing thorium-uranium breeder reactor and for burning transuranium elements from the spent fuel of power reactors are described. Such a reactor is characterized by fuel-cycle flexibility, since it is capable of operating with a wide spectrum of fuel and raw-materials loads without being stopped or structurally altered. Compared with thermal liquid-salt reactors with a graphite moderator, these reactors have deeply negative temperature coefficients of reactivity (–7·10–5°C–1), and the fuel salt is completely processed in 3–4 years. Such a reactor facility can be incorporated into any strategy for the development of nuclear power.

There is presented the information on the projects developed by the JSC “Turboatom” for the new steam turbines intended for the thermal power stations. There are considered the ways of the operating characteristics enhancement of the turbo-units manufactured earlier.

Experimental measurements of the basic physical properties of the melt NaF-LiF-BeF2 are presented as validation of the concept of a molten-salt reactor for burning actinides from spent fuel from light-water reactors. Compositions which are characterized by the minimal molar fraction LiF 15–17% and BeF2 25–27% and meet the special requirements for a fuel salt for the concept under study are found. The melts of the fluorides of three metals have an acceptable melting temperature (

The results of tests of the compatibility of nickel-based alloys and metal-fluoride melts are generalized for molten-salt reactors.

We have studied the dependence of the production cross-sections of the isotopes 282,283112 and 286–288114 on the excitation energy of the compound nuclei 286112 and 290114. The maximum cross-sections of the xn-evaporation channels for the reaction 238U(48Ca,xn)286-x 112 were measured to be: σ 3n = 2.5 -1.1 +1.8 pb and σ 4n = 0.6 -0.5 +1.6 pb; for the reaction 242Pu(48Ca,xn)290-x 114: σ 2n ∼ 0.5 pb, σ 3n = 3.6 -1.7 +3.4 pb and σ 4n = 4.5 -1.9 +3.6 pb. In the reaction 233U(48Ca, 2-4n)277–279 112 we measured an upper cross-section limit of σ xn ≤ 0.6 pb. An increase of σ ER in the reactions of actinide targets with 48Ca can be due to the expected increase of the survivability of the excited compound nucleus upon closer approach to the closed neutron shell N = 184. The observed nuclear decay properties of the nuclides with Z = 104–118 are compared with theoretical nuclear mass calculations and the systematic trends of α-decay properties. As a whole, they give a consistent pattern of decay of the 18 even-Z neutron-rich nuclides with Z = 104–118 and N = 163–177.

PC-based detection system for heavy element research at the Dubna Gas-filled Recoil Separator is presented. It allows to operate with the experimental data obtained from the detection system of GFRS which consists of 12-strip silicon position sensitive detector and two multiwire low-pressure proportional gaseous chambers to generate time-of-flight signal of incoming charge particles. Special attention is payed to the detection of genetically linked recoil-alpha sequences in a real-time mode. The results of the experiment aimed at the synthesis of new Z=113–115 elements with the mentioned technique are presented in brief.

Formulation and solution of the problem of the U‐400 cyclotron arc ion source mode control optimization are considered. The optimization criterion is formulated as follows: to get the preset or maximum beam current in a limited range of the discharge and sputtering parameters. The ion source mode control is fulfilled by six input parameters variation. The algorithms of control are realized on the basis of CAMAC crate microprocessor controller and microcomputer compatible with IBM PC/XT/AT.