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The recent paper is devoted to design, manufacturing and testing the permanent magnet system to be used for Positron Emission Tomography (PET) cyclotron. The using permanent magnet material instead of copper coils allows essential electric power savings during PET cyclotron operation, though it comes to some increasing construction cost. The main problem why until now permanent magnets were not used for PET cyclotron magnet system is huge magnetic force, making cyclotron assembling/disassembling and isochronous magnetic field adjustment very difficult. For presented magnet system that problem is solved by applying rotating system providing the magnetic field switch-off (reduction to practically zero level inside working aperture). It makes assembling and adjustment easy at force free conditions. The main parameters of permanent magnet system are as follows: the average field is 1.4 T, pole radius is 375 mm and weight is 900 kg. As it shown in paper the magnetic properties of constructed permanent magnet system does satisfy to specification for magnet system of typical 10 MeV cyclotron for PET radioisotope production.

An ultra compact cyclotron was constructed for Particle Induced X-ray Emission (PIXE) and Rutherford Back Scattering (RBS) experiments. The cyclotron accelerates proton and alpha-particle beams to a constant energy of 3 MeV. The size of the magnet is 85 cm ×85 cm ×60 cm . Characteristics of the cyclotron are presented.

A moderately thermophilic iron-oxidizing bacterium strain TI-1 produced 74 μmol H2S extracellularly when grown at 45°C for 15 days in 20 mL of ferrous sulfate-5AAG medium (pH 4.0) containing 1.0 % elemental sulfur and 0.31 % L-glutamic acid. Precipitation of copper from a leaching solution by the H2S produced by strain TI-1 was investigated. A leaching solution containg Cu2+ was prepared by the cultivation of Thiobacillus ferrooxidans AP19-3 on a copper concentrate (5.0 %)-medium (pH 2.5) for 15 days. When strain TI-1 was grown for 8 days in a ferrous sulfate-5AAG medium (pH 4.0) containing 1.0 % elemental sulfur, 0.31 % L-glutamic acid and 5 mM Cu2+ from a leaching solution, the Cu2+ in the medium was completely precipitated by the H2S produced by strain TI-1. Growth of strain TI-1 in ferrous sulfate-5AAG medium was not inhibited by 10 mM Cu2+. A moderately thermophilic sulfate-reducing bacterium Desulfotomaculum nigrificans IFO 136987 produced 45 μmol H2S extracellularly when grown at 45°C for 15 days in 20 ml of lactate (0.35 %)-medium. The maximum productivity of H2S by D. nigrificans was observed in the medium with an initial pH of 7.2. The bacterium did not produce H2S in the lactatemedium with a pH less than 6.0. Growth of D. nigrificans in the lactate-medium was completely inhibited by 0.56 mM Cu2+. These results suggest that strain TI-1 is superior to D. nigrificans in the ability to precipitate copper from the acidic leaching solution containing Cu2+.