The experiments were performed at bremsstrahlung end-point energies of 10-23 MeV with the beam from the MT-25 microtron with the use of the γ-activation technique. The experimental values of relative yields were compared with theoretical results obtained on the basis of TALYS with the standard parameters and the combined model of photonucleon reactions. Including isospin splitting in the combined model of photonucleon reactions allows to describe experimental data on reactions with proton escape in energies range from 10 to 23 MeV. Therefore, taking into account isospin splitting is necessary for a correct description of the decay of the GDR.

Relative yields have been measured in the 40-130 MeV bremsstrahlung induced reactions of 59Co. The experiments have been performed with the beam from the electron linear accelerator LINAC-200 using the activation and off-line γ-ray spectrometric technique. The bremsstrahlung photon flux has been calculated with the Geant4 program. The cross sections were calculated by using computer code TALYS-1.96 with different models and are found to be in good agreement with the experimental data.

For photonuclear research with γ-quanta having energies Eγ ≤ 40 MeV at the source under developing with backward Compton scattering of laser radiation on accelerated electrons, activation experiments are proposed as initial ones. These experiments are important both for developing techniques for tuning and monitoring such γ-beams, and for studying the excitation of pygmy and giant resonances in nuclei at Eγ near the threshold of the (γ, n) reaction, as well as the multiplicity of photoneutrons during deexcitation of giant resonances at Eγ above the threshold of (γ, 2n)-reaction.

To study the E1 giant resonance in atomic nuclei, it is important to study the energy and emission angle distributions of fast neutrons from (γ, n)-reactions. The paper considers some features of such studies on beams of γ-quanta produced by inverse Compton scattering with small spreads of their energy, angles, transverse dimensions, duration, and polarization in these beams. It is proposed to use fast neutron spectrometers using both amplitude and time-of-flight data.

Based on the analysis of development of photonuclear reaction studding at 𝐸𝛾 ≲ 40 MeV and the unique parameters of the Compton source of 𝛾–quanta under projecting, a program of priority photonuclear research using this source is proposed. The program includes research on: structures of giant E1 resonances and pygmy resonances; cross sections for partial photonucleon reactions; nuclear resonant fluorescence; photofission; problems of astrophysics and nucleosynthesis.

The flux weighted average cross sections 〈σ〉 and cross sections per equivalent photon σq were first measured for the photonuclear multiparticle reactions natSe(γ, xnyp) at end-point bremsstrahlung gamma energies ranging from 20 to 80 MeV. The experiments were performed with the beam from the electron linear accelerator LINAC-200 with the use of the γ-activation technique. The bremsstrahlung photon flux was calculated with the program Geant4. The theoretical values of the flux weighted average cross sections 〈σ〉 and the cross sections per equivalent photon σq were calculated using the partial cross section σ(E) computed with the TALYS package code and the combined model of photonuclear reactions.

Proceeding from the comparison of parameters for the γ -ray source based on backward Compton scattering, which is under development now, and the known methods of monitoring γ -ray beams themselves to monitor the intensity and energy spectrum of γ quanta in the beams from this γ -ray source during photonicuclear research in the energy range from a few megaelectronvolts to ∼ 40 MeV, a system comprising scintillation plastic and inorganic detectors, as well as a magnetic pair spectrometer, has been proposed.

The production possibility of 161Tb and 155Tb by irradiating of natural dysprosium with gamma rays obtained by decelerating an electron beam with an energy of 55 MeV has been demonstrated experimentally. The yield of 161Tb was 14.4 x 103 Bq x mu A-1 x h-1 x cm2 x gDy2O3- 1. Simultaneously, upon irradiation, 155Dy is formed with the yield of 25 x 103 Bq x mu A-1 x h-1 x cm2 x gDy2O3- 1, which leads to the formation of 1.6 x 103 Bq x mu A-1 x h-1 x cm2 x gDy2O3- 1 of 155Tb. It has been shown that the isolation of terbium radioisotopes from tens of mg of dysprosium target can be achieved by extraction chromatography, and final separation yield was 39%. The impurity of 160Tb is 7.3% of the 161Tb activity at EOB.

Based on a comparison of the parameters of the projected 𝛾–source from backward Compton scattering and the known ways of monitoring the beams of 𝛾–quanta themselves to monitor the intensity and energy spectrum of 𝛾–quanta in their beams at this 𝛾–source in photonuclear studies in the region from several MeV to ∼40 MeV, a system of scintillation plastic and inorganic detectors, as well as a pair magnetic spectrometer, was proposed.

The method of induced activity was used to study photonuclear reactions on natural mixture of selenium isotopes. This study measured the yields of the radionuclides ^73g Se, ^73m Se, ^73g+m Se, ^79m Se, ^81g Se, ^81m Se, ^81g+m As, ^72 As, ^73 As, ^74 As, ^76 As, ^77 As, ^78 As, and ^79 As produced in ^nat Se( γ,xnyp ) multiparticle reactions with bremsstrahlung end-point energy of 55 MeV. The bremsstrahlung radiation was generated using the RM-55 electron accelerator at the Skobeltsyn Institute of Nuclear Physics, Moscow State University, and the reaction yields were derived from the induced activities measured using off-line γ -ray spectrometry. The measurement of the production yields for the radionuclides produced in the photoproton reactions on natural selenium is the first of its kind. The experimentally obtained yields of photonuclear reactions are compared with the yields calculated using theoretical cross-sections of photonuclear reactions within the combined model of photonuclear reactions and the TALYS program code.

Formation of Yb and Tm radioisotopes upon irradiation of ytterbium of natural isotopic composition by bremsstrahlung photons with energies up to 55 MeV was studied. The yield of the medical radionuclide Tm-167 was (7.8 +/- 1.1) x 10(3) Bq x mu A(-1) x h(-1) x cm(2) x g(-1). Thulium radioisotopes were separated from irradiated ytterbium target by extraction chromatography on the LN Resin sorbent in nitric media. Efficient separation of tracer amounts of thulium from tens of milligrams of ytterbium could be achieved. The method can be of practical importance for the production of Tm-167 when using a Yb-168 enriched target.

Carboxamides and carbamoyl oximes containing both adamantyl and 3,6-diazahomoadamantyl fragments were synthesized. The reactions proceed in mild conditions and in high yields. The synthesized compounds are promising as soluble epoxide hydrolase inhibitors.

Синтезированы карбоксамиды и карбамоилоксимы содержащие одновременно адамантильный и 3,6-диазагомоадамантильный фрагменты. Реакции протекают с высокими выходами целевых продуктов в мягких условиях. Полученные соединения перспективны в качестве ингибиторов растворимой эпоксигидролазы.

The condensation product of adamantan-1-amine with formaldehyde, 1,3,5-tri(1-adamantyl)-1,3,5-triazacyclohexane, was treated with three different types of ketones: symmetric (RCH 2 ) 2 CO, nonsymmetric RCH 2 COCH 3 , and acetone to obtain 1,5-R- N , N ′-di(1-adamantyl) bispidin-9-ones, N , N ′-di(1-adamantyl)-1-[(1-adamantylamino)methyl]-5-methylbispidin-9-one, and N , N ′-di(1-adamantyl)-1,5-bis[(1-adamantylamino)methyl]bispidin-9-one. 1,5-R- N , N ′-Di(1-adamantyl)bispidin-9-ones were reduced with sodium borohydride to 1,5-R- N , N ′-di(1-adamantyl)bispidin-9-ols.

The yields of photonuclear reactions on mixtures of natural isotopes of strontium and molybdenum that result in the formation and decay of bypassed nuclei 84Sr and 92Mo are measured and compared to theoretical results obtained using the TALYS code and calculations in the combined model of photonucleon reaction (CMPR). The need is demonstrated to consider isospin splitting in cases of photoproton reactions. The yields of the 92Mo(γ,p)91mNb, 84Sr(γ,p)83Rb reactions that make the main contribution to the formation and decay of 84Sr and 92Mo in the p-process of nucleosynthesis differ from the TALYS and CMPR results by several hundred percent.

The role of (γ, 2n), (γ, pn), and (γ, 2p) multiparticle photonuclear reactions in processes that lead to the nucleosynthesis of p-nuclides is considered. The library of rates of multiparticle photonuclear reactions that was developed for the temperature range between 1 and 10 GK and which is intended for use in stellar-evolution models and in calculations of nucleosynthesis is described. A simulation of the p-process in the course of an SN-IIa core-collapse event reveals that, within the scenario being considered, a dominant effect of multiparticle photonuclear reactions consists in enhancing the rate of photodisintegration of p-nuclides at temperatures above 6 to 7 GK.