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“Off-the-shelf” clinical linear electron accelerators (LINAC) have been suggested as alternative to research accelerators once they are no longer suitable for the medical applications. We investigated feasibility of utilising a modified LINAC for instrumental photon activation analysis (IPAA) as a tool in environmental geochemistry studies. The IPAA results were compared with those obtained using a MT-25 research accelerator at Joint Institute for Nuclear Research in Dubna, Russia. To investigate soil pollution in Antalya, Turkey, 90 surface soil samples were analysed and significant enrichments of Ni, Cr and As were found.

This work presents the experimental study of the isomeric ratio of 137mCe–137gCe produced in 138Ce(γ, n) 137m,gCe photonuclear reaction, in neutron capture reaction 136Ce(n, γ) 137m,gCe and in the two simultaneous reactions 138Ce(γ, n) 137m,gCe and 136Ce(n, γ) 137m,gCe in the mixed photon—neutron field by the activation method. The investigated samples were irradiated at the bremsstrahlung photon flux, in the epithermal and thermal-epithermal neutron beam and in the mixed photon-neutron field constructed at the electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The results were analyzed, discussed and compared with those of other authors to examine the role of the channel effect in nuclear reaction and provide the nuclear data for theoretical model interpretation of nuclear reactions.

The isomeric ratios in 138Ce(γ, n)137m,gCe photonuclear reaction have been measured for energy ranges from 14 to 17, 21 to 23 and at 19 MeV end-point bremsstrahlung energies by the activation method. In order to improve the accuracy of the experimental results, necessary corrections and data analysis were made in the γ-ray activity measurements. The results were analyzed, discussed and compared with the similar data from literature to examine the role of excitation energy and the influence of channel effects. The above obtained data are the first time measurements.

We measured for the first time the isomeric ratios in 107Ag(γ, n)106m,gAg reaction by using the activation method and γ-ray spectroscopic method for the whole giant dipole resonance region. The high-purity natural Ag foils in disc shape were irradiated with bremsstrahlungs generated from an electron accelerator Microtron. The induced gamma spectra in the irradiated foils were measured by the high resolution γ-ray spectroscopic system which consists of a high-purity germanium detector and a multichannel analyzer. In order to improve the accuracy of the experimental results, necessary corrections were made in the γ-ray activity measurements and data analysis. The results were analyzed, discussed and compared with those of other authors. For the above mentioned reaction, the isomeric ratios in the energy range from 14 to 24 MeV bremsstrahlungs in this work (except the values at 14, 18 and 20) are new measurements.

We have determined the isomeric ratios in 113In(γ, n)112m,gIn and 113In(γ, 2n)111m,gIn photonuclear reactions of natural indium induced by bremsstrahlungs with end-point energies in the giant dipole resonance (GDR) region. The investigated samples were irradiated at the electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, Dubna. The gamma spectra of the samples irradiated were measured with a spectroscopic system consisting of an 8192-channel analyzer and a high-energy resolution (180 keV at gamma ray 1332 keV of 60Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors. For both the mentioned reactions, the isomeric ratios in the bremsstrahlung energy range from 19 to 24 MeV in this work are new measurements.

We have determined the isomeric ratios in 120Te(γ, n)119m,gTe, 122Te(γ, n)121m,gTe, 128Te(γ, n)127m,gTe and 130Te(γ, n)129m,gTe photonuclear reactions of natural tellurium induced by bremsstrahlungs with end-point energies in the giant dipole resonance (GDR) region. The investigated samples were irradiated at electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The gamma spectra of the samples irradiated were measured with spectroscopic system consisting of 8192 channel analyzer and high-energy resolution (180 keV at gamma ray 1,332 keV of 60Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors.

Twenty six elements was studied preliminary i n the superficial sediments of Havana Bay using gamma activation analysis by the electron accelerator microtron MT -25 at the Flerov Laboratory of Nuclear Reactions, JINR. Samples from five zones of Havana Bay including the three coves were analyzed. The ob tained results show a close relation between the concentration levels of the studied elements and the pollution sources. Some elements (As, Ba, Ni, Pb, Cu, Zn, Fe, Cr, Mn) have high concentration levels compared to the values for other environmental marine sediments reported in the literature.

The electrophoresis of zirconium and hafnium ions in aqueous solutions was investigated. No-carrier-added 88Zr and 175Hf have been used in microconcentrations (10-11M). The complexation of zirconium and hafnium with DTPA has been investigated in a large pH interval. The stability constants of the Zr-DTPA and Hf-DTPA complexes were determined for the first time by the method of horizontal zone electrophoresis in free electrolyte. The electrophoretic behavior of Zr(IV) and Hf(IV) ions in nitric acid solutions has also been studied.

The electrophoretic method was recently developed for the determination of diffusion coefficients of ions in aqueous solution. By solving the Fick's second law in the presence of unlimited media and constant quantity of diffusing species we obtain a relationship between the diffusion coefficient and the standard deviation of the distribution profile. The diffusion coefficients of Cd(II), In(III), Zr(IV), Hf(IV), Pu(VI) and [InDTPA]2− in nitric acid solution were determined as well as the effective charge of In-DTPA complex at pH 4.50.

We have determined the isomeric ratios of isomeric pairs 194m,gIr and 197m,gPt produced in 195Pt(γ, p)194Ir and 198Pt(γ, n)197Pt photonuclear reactions in the giant dipole resonance (GDR) region by the activation method. The results were analyzed, discussed and compared with the similar data from literature to examine the role of excitation energy and difference in the isomeric and ground state spins. The isomeric ratios of 194m,gIr and 197m,gPt from the present work, namely from 19 to 23 MeV for 194m,gIr and from 18 to 24 MeV for 197m,gPt are the first time measurements.

A new highly sensitive track method for the determination of thorium (232Th) and neptunium (237Np) has been developed. The technique includes the radiochemical separation procedure of the isotopes followed by the irradiation of the resultant samples on the MT-25 microtron. The detection limit is equivalent up to 3·10−13 g of232Th and 7·10−14 of237Np. The method was used to determine232Th and237Np isotopes in water samples.