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Method for production of alpha emitter 149Tb by irradiation of 151Eu with 70 MeV 3He nuclei is proposed. For the first time, the cross sections for the formation of isotopes 149,150,151,152Tb were measured experimentally using a stack foil technique in the 3He particles energy range 70 → 12 MeV. The thick target yield of 149Tb is 39 MBq/μAh, or 230 MBq/μA 149Tb at saturation. The optimal energy range from the point of view of radioisotopic purity is 70 → 40 MeV. At these conditions about 150 MBq/μA 149Tb can be produced in 8 hours irradiation, which is sufficient for therapeutic applications. The main impurities are 150Tb (~100% in activity) and 151Tb (~30% in activity). The proposed method surpasses its counterparts by the high content of the target isotope in the natural mixture and the simplicity of the radiochemical separation of 149Tb from the bulk target material.

The irradiations of Ag to Sn targets by bremsstrahlung generated with 23-MeV electron beams are performed at the MT-25 microtron. Gamma spectra of the induced activities have been measured and the yields of all detected radionuclides and isomers are carefully measured and analyzed. A regular dependence of yields versus changed reaction threshold is confirmed. Many isomers are detected and the suppression of the production probability is observed with growing product spin. Special peculiarities for the isomer-to-ground state ratios were deduced for the 106mAg, 108mAg, 113mIn, 115mIn, and 123mSn isomers. The production of such nuclides as 108mAg, 115mIn, 117gIn, and 113mCd is of interest for applications, especially when economic methods are available.

A procedure was developed for selective separation of Group IV elements from Sr and Lu, followed by rapid separation of Zr and Hf by cation-exchange chromatography in dilute HCl/HF solutions. The possibility of using this procedure for chemical identification and determination of decay parameters of the new isotope 267Rf was demonstrated.

The process of uranium photofission with electron beams of 20–50 MeV is considered in terms of the production of fission fragments. It is shown that in the interaction between an electron beam (25 MeV in energy and 20 μA in intensity), produced by a compact accelerator of the microtron type, and a uranium target of about 40 g/cm 2 in thickness, an average of 1.5×10 11 fission events per second is generated. According to the calculations and test experiments, this corresponds to the yield of 132 Sn and 142 Xe isotopes of approximately 2×10 9 /s. The results of experiments on the optimal design of the U-target are presented. Problems are discussed connected with the separation of isotopes and isobars for their further acceleration up to energies of 5–18 MeV A . The photofission reactions of a heavy nucleus are compared with other methods of RIB production of medium mass nuclei.

A 111In → 111m Cd radionuclide generator with the chemical yield higher than 95% and content of parent isotope (1 1 1In) in the 1 1 1m Cd preparation less then 0.6% (relative to the activity of the target nuclide) was developed. Parent and daughter radionuclides were separated by extraction chromatography using di-2-ethylhexyl hydrogen phosphate. The probability of electron capture to the 396-keV isomeric state (1 1 1 m Cd) in 1 1 1In decay is (6.01±0.14r a n d o m±0.18s y s)×10- 5.

A rapid method for the preparation of 87Y/87mSr radionuclide generator from a rubidium chloride target irradiated with 35 MeV α-particles is described. A simple two-step procedure is used to obtain a carrier-free 87mSr isotope with a high enough radiochemical yield and high purity in the final aqueous fraction.

The present study has been performed within the framework of experiments aimed at the investigation of chemical properties of long‐lived Db isotopes in aqueous solutions. The isocratic anion exchange separations of group V elements in the solutions containing HF have been considered. Parameters of separation of dubnium homologues (Pa, Nb and Ta) in HF/HNO3 mixed solutions have been optimized. The procedure of separation of group V elements from multicomponent system has been suggested.

26Al is a positron emitting radioisotope of aluminium and has a half-life of 7.16×105y. In addition to annihilation γ-rays of 511 keV, there are three high energy γ-rays 1129 (2.4%), 1809 (99.73%) and 2938 (0.27%) keV.26Al is the only radioisotope of aluminium available for radiochemical applications, the half-lives of the other aluminium isotopes are seconds and minutes. The usage of26Al is very important in the investigations of the metabolism of Al in human body (for example in Alzheimer disease studies) or as a tracer in radiochemical studies. But26Al is such a long-lived isotope that the task of producing it in tangible amounts is a very difficult one.