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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.

Currently there is no clear guidance on the management of patients with concomitant chronic diseases of the veins (CVD), such as varicose and postthrombotic disease of the lower limbs, with endoprosthetics of the knee or hip joint. To reduce the risk of thromboembolic complications in patients of this group, the authors developed individual algorithms of reference.

The authors adapt recently developed a large eddy simulation / extended partially stirred reactor (LES/EPaSR) model by Sabelnikov and Fureby for simulation of turbulent combustion to Reynolds-averaged Navier–Stokes (RANS) equations. The proposed RANS/EPaSR model is validated against experimental database created at ONERA for an air–methane premixed flame stabilized by a backward-facing step combustor. The RANS/EPaSR model is compared also with the following RANSbased combustion models: (i) quasi-laminar model with reduced chemical mechanism (QL RCM); (ii) premixed flamelet tabulated chemistry (PFTC) without taking into account the turbulence–chemistry interaction (TCI); and (iii) a PFTC with a presumed β probability density function (PDF) for a progress combustion variable.

The search for new decay chains of oganesson isotopes is presented. The experiment utilized the Dubna Gas Filled Recoil Separator and a highly segmented recoil-decay detection system. The signals from all detectors were analyzed in parallel by digital and analog data acquisition systems. For the first time, a target of mixed californium (51% Cf249, 13% Cf250, and 36% Cf251) recovered from decayed Cf252 sources was produced and irradiated with an intense Ca48 beam. The observation of a new decay chain of Og294 is reported. The prospects for reaching new isotopes Og295,296 are discussed.

Gas-phase chromatography studies of nihonium (Nh, $Z=113$ ) were carried out at the one-atom-at-a-time level. For the production of nihonium, the heavy-ion-induced nuclear fusion reaction of 48Ca with 243Am was used. This leads to isotopes 284,285Nh, as the direct descendants of the $\alpha$ -decaying precursors 288,289Mc. Combining the Dubna Gas-Filled Recoil Separator with gas-phase chromatographic separation, the experiment was sensitive to elemental nihonium and its adsorption behavior on Teflon, theoretically predicted by modern relativistic density functional theory. The non-observation of any decays of Nh after the chemical separation indicates a larger than expected retention of elemental Nh on a Teflon surface.

First experimental results of a chemical investigation of element 113 independently confirm the synthesis of the new elements 115 and 113 in the nuclear fusion reaction of Ca 48 + Am 243 and indicate a chemical behaviour resembling a species with a high volatility a weak interaction with inert surfaces and an enhanced reactivity towards gold surfaces.

Previously reported preparation method for Pd-based intermetallic targets (Usoltsev, et al., 2012) [1] has been successfully applied for producing two stationary 243Am/Pd targets. Both targets have been irradiated at the U-400 cyclotron at Flerov Laboratory of Nuclear Reactions Dubna (Russian Federation) using high intensity beams (up to 0.83 μApart) of 48Ca18+. Alpha-particle spectroscopy and light microscopy allowed for a comprehensive characterization of the intermetallic targets before and after irradiation. A natNd/Pd intermetallic target and a solely electroplated 243Am/Ti target were similarly investigated for comparison.

The adsorption behavior of 197Hg and 183–185Hg on red amorphous selenium (red a-Se) and trigonal selenium (t-Se) was investigated experimentally by off-line and on-line gas chromatographic methods, in preparation of a sensitive chemical separation and characterization of the transactinides copernicium (Cn, Z = 112) and flerovium (Fl, Z = 114). Monte-Carlo simulations of a diffusion controlled deposition were in good agreement with the experimental results, assuming as interaction limits −ΔH ads red a-Se (Hg) > 85 kJ/mol, and −ΔH ads t-Se (Hg)

Irradiations of $^{239}\mathrm{Pu}$ and $^{240}\mathrm{Pu}$ targets with $^{48}\mathrm{Ca}$ beams aimed at the synthesis of $Z=114$ flerovium isotopes were performed at the Dubna Gas Filled Recoil Separator. A new spontaneously fissioning (SF) isotope $^{284}\mathrm{Fl}$ was produced for the first time in the $^{240}\mathrm{Pu}+^{48}\mathrm{Ca}$ (250 MeV) and $^{239}\mathrm{Pu}+^{48}\mathrm{Ca}$ (245 MeV) reactions. The cross section of the $^{239}\mathrm{Pu}(^{48}\mathrm{Ca},3n)^{284}\mathrm{Fl}$ reaction channel was about 20 times lower than predicted by theoretical models and about 50 times lower than the maximum fusion-evaporation cross section for the $3n$ and $4n$ channels measured in the $^{244}\mathrm{Pu}+^{48}\mathrm{Ca}$ reaction. In the $^{240}\mathrm{Pu}+^{48}\mathrm{Ca}$ experiment, performed at 245 MeV in order to maximize the $3n$-evaporation channel, three decay chains of $^{285}\mathrm{Fl}$ were detected. The $\ensuremath{\alpha}$-decay energy of $^{285}\mathrm{Fl}$ was measured for the first time and decay properties of its descendants $^{281}\mathrm{Cn}, ^{277}\mathrm{Ds}, ^{273}\mathrm{Hs}, ^{269}\mathrm{Sg}$, and $^{265}\mathrm{Rf}$ were determined with higher accuracy. The assignment of SF events observed during the irradiation of the $^{240}\mathrm{Pu}$ target with a 250 MeV $^{48}\mathrm{Ca}$ beam to $^{284}\mathrm{Fl}$ decay is presented and discussed. The cross sections at both $^{48}\mathrm{Ca}$ energies are similar and exceed that observed in the reaction with the lighter isotope $^{239}\mathrm{Pu}$ by a factor of 10. The decay properties of the synthesized nuclei and their production cross sections indicate a rapid decrease of stability of superheavy nuclei as the neutron number decreases from the predicted magic neutron number $N=184$.

Molybdenum-99 was prepared by 100Mo(γ,n) photonuclear reaction on an electron accelerator, MT-25 microtron (FLNR). Natural Mo foil (9.6% 100Mo) and 100MoO3 (100% 100Mo) were used as the targets. The radiation yield of 99Mo was 3.2 kBq/(μA h mg 100Mo). Technetium-99m was isolated from the target material and concomitant radioactive impurities by an ion-exchange procedure. The possibility of preparing 99mTc generator from molybdenum carbonyl was studied. The content of radioactive impurities in the final 99mTc preparations was no higher than 10−5 Bq Bq−1.

In the framework of the Project DRIBs (Dubna Radioactive Ion Beams) the photofission reaction 238U(γ, f) has been studied at the FLNR (JINR) in view of producing beams of neutron-rich radioactive nuclei 132Sn and 142Xe using the MT-25 microtron [1].

225Ac was prepared by the 226Ra(γ, n) reaction on an electron accelerator (MT-25 microtron) at FLNR. The radiation yield of 225Ac was 550 Bq/(μA h mg 226Ra). 225Ac was isolated from the target material and radioactive impurities by the ion-exchange procedure. The 225Ac:227Ac:226Ra activity ratio in the preparation was 1:∼2 × 10−9:≤6 × 10−5.

The work on isotopically pure 26 Al, 97 Ru, 178 W/ 178 Ta, 235 Np, 236 Pu and 237 Pu production was initiated because of intensive research on their applications in the biomedical field and environmental chemistry. The conditions for isotopically pure production have been investigated. This paper describes the data for the nuclear reactions of the radionuclide production, the different target designs and target chemistry procedures.

The ultimate objective of this work was to enhance the performance of air-breathing engines in transient modes. The paper presents the results of laboratory-scale experiments on ignition of nonpremixed fuel air composition in high-speed §ow by a near-surface electrical discharge. The experiments were ful¦lled under conditions of model supersonic combustor on the plane wall without any mechanical §ameholder. The ignition and §ameholding of hydrogen air and ethylene air compositions were demonstrated for direct fuel injection into the §ow at low (T0 = 300 750 K) gas temperature. The deposited power was Wpl/Htot 0.9, with both hydrogen and ethylene fuels under optimal conditions.

A short review of the current data concerning nuclear reactions, target chemistry and following applications of some radioisotopes as tracers is given in this report.