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The radionuclides (88)Zr and (89)Zr have been produced by cyclotron irradiation of (nat)SrO with 35 MeV α-particles at a beam current of 15 μA. The thick source production yield of (89)Zr is ~3.1 MBq μA(-1) h(-1). A two-step radiochemical purification utilising anion-exchange chromatography in hydrochloric and hydrofluoric acids has been developed to separate (88,89)Zr from the target material, natural strontium, the target substrate, aluminium, and long-lived (88)Y.

A method to produce (117m)Sn radionuclide using accelerator production route is described. A new method is proposed to separate the (117m)Sn. Specific activities and thick target yield for (116)Cd(α,3n)(117m)Sn reaction at E(α)=35MeV bombarding energy were determined. The estimated production yield of (117m)Sn was 37.5kBq/μAh for 13.16 mg/cm(2) natural cadmium-oxide target and 410 kBq/μAh for 11.07 mg/cm(2) highly enriched (95%) (116)CdO target. The method developed for separation of (117m)Sn from Cd using anion-exchange resin (Dowex -1×8, fluorine form, 400 mesh) can achieve 98% radiochemical yield of (117m)Sn with more than 99% radionuclidic purity. The estimated specific activity is 2.4 GBq/mg that can be reached with the used irradiation conditions.

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.

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.

237 Pu (half-life 45.3 d) is a valid metabolic tracer for the long-lived isotopes of plutonium, but its use in human subjects has previously been restricted by difficulties in producing it with acceptable isotopic purity. These difficulties have been overcome by applying mass-separation techniques to the impure product of irradiating 235 U with 25-MeV 4 He + ions.

Isotopically pure 236Pu (>99.999% by activity) has been produced by irradiating U (95% 235U) with 4He ions and refining the product by electromagnetic mass separation. Further developments in the production of 237Pu are also reported, giving material containing, by activity, only 3 × 10−6% 236Pu and probably only ∼ 10−5% 238Pu.