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To measure the total neutron cross sections, the authors developed a convenient technique using silicon semiconductor detectors with the simple and compact detecting system. The created technique was used to measure A + n total cross sections at the energy En = 14.1 MeV for several nuclei in different mass region. The neutron generator NG-150 in D + T regime of neutrons generation is used as fast neutrons source. The results of measurements and their comparison with the appropriate literature values are also presented.

The Geant4 code is used for Monte Carlo modeling of the angular distribution of the neutron yield from an 3H(d, n)4He reaction in a tritium target, and the effect the collimator unit has on the neutron flux. The number of all nuclear reaction channels in a 232Th + natU (50/50%) target per 14.1-MeV neutron is also found, along with the optimum size of the target for the maximum yield of secondary neutrons.

Using the methods of X-ray photoelectron spectroscopy (XPES), X-ray phase analysis, gamma-resonance (Mossbauer) spectroscopy, thermogravimetry of solid samples and atomic absorption, and atomic emission spectroscopy for solutions, the forms of occurrence of nonferrous metals in oxyhydroxide sediments (nitration hydroxides, NH) from nitration of refining of rhodium, iridium, and ruthenium are investigated. According to the XPES data, nitration hydroxides involve oxidized and unoxidized (selenium) transition metals, namely, Fe(III), Sn(II), Te(IV), Cu(I), Cu(II), Ni(II), Pb(II), As(III), Se(0), and Se(IV), as well as nonmetals O, Cl, and C. All nitration hydroxides are formed mainly by an X-ray amorphous phase (>90%). During heating of nitration hydroxides up to t = 900°C in an inert atmosphere, dehydration of hydroxides and crystallization of certain phases take place, but the X-ray amorphous phase amounts to more than 50%. Purely oxide phases or mixed oxide phases Fe3O4, SnO2, CuIFeIIIO2, and Pb2O3 (NH-1); Ni0.4Fe2.6O4, CuIFeIIIO2, and CuNiSnO4 (NH-2); and Fe3O4, Fe2O3, and SnO2 (NH-3) are formed in this case.