The removal of cesium and cobalt radionuclides from aqueous chloride solutions using hydrous titanium oxide was investigated. The influence of initial ion concentration, pH, and temperature has been reported. The data obtained have been correlated with Langumir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models. The effect of temperature on the equilibrium distribution values has been investigated. The thermodynamic parameters such as free energy (ΔG^o), enthalpy (ΔH^o) and entropy (ΔS^o) have been calculated. Maximum ion exchange capacity and the mean free energy of each studied ion have been determined using D-R isotherm model.

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Instrumental neutron activation analysis (INAA) using high resolution γ-ray spectrometry was used to determine concentrations of 20 elements in seven clay pottery samples collected from excavated Buddhist sites of four districts of Andhra Pradesh, India. For determining accuracy of the INAA method, two certified reference materials (CRMs) namely SL-1 and Soil-7 obtained from IAEA were analyzed. For establishing the provenance (same or different origin) of pottery samples, Al to Sc concentration ratio as well as statistical cluster analysis was used. For the cluster analysis, concentration values of selected nine elements namely Sc, Cr, Mn, Fe, Co, Rb, Cs, Ba, and Hf were used. Soil samples from corresponding sites with known origin were analyzed for the validation of provenance methodology adopted in this study. From these analyses, it was observed that both pottery and soil samples under study belong to four different groups. To the best of our knowledge, the provenance studies of these ancient pottery samples are reported for the first time.

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Ago Bay in Mie Prefecture, central Japan, is world-famous for the site of Mikimoto pearl culture, but recently the production of pearls has considerably declined. Environmental deterioration of the bay is suspected of having caused the decline. The periodic investigation into iron speciation of the bay sediment by ⁵⁷Fe Mössbauer spectroscopy revealed its high pyrite (FeS₂) content from the surface to the 20-cm depth. The pyrite in the surface sediment decreased only in spring, three months after the dissolved oxygen in the bottom water was at maximum. Such oxygen-consuming material as pyrite accumulated through long-term biotic activity is a most-likely explanation for the prolonged environmental deterioration of the bay, which appears in the high chemical oxygen demand (COD) of the sediment.

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Empirical formulas were obtained for estimation of the prompt neutron multiplicity for actinides as a function of the incident neutron energy. Measured data for eleven nuclides (²³²Th, ²³³U, ²³⁵U, ²³⁸U, ²³⁷Np, ²³⁹Pu, ²⁴⁰Pu, ²⁴¹Pu, ²⁴¹Am, ²⁴³Am, and ²⁴⁵Cm) were used as the basis to extract systematic relations of slopes and intercepts of a linear function of the prompt neutron multiplicity. The obtained formulas were compared with available measured data and existing evaluations. It was found that these formulas could be used to estimate the quantity for nuclides for which no or scarce data is available.

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The performance of the gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator GARIS was investigated using ²⁵⁵No produced in the ²³⁸U(²²Ne, 5n)²⁵⁵No reaction. Alpha particles of ²⁵⁵No separated with GARIS and transported by the gas-jet system were measured with a rotating wheel apparatus for α spectrometry under low background condition. The high gas-jet efficiencies of about 75% were independent of the recoil ranges of ²⁵⁵No in the gas-jet chamber. The present results suggest that the GARIS/gas-jet system is a promising tool for the next-generation superheavy element chemistry: (i) the background radioactivities of unwanted reaction products are strongly suppressed, (ii) the intense beam is absent in the gas-jet chamber and hence the high gas-jet efficiency is achieved, and (iii) the beam-free condition also allows for investigations of new chemical systems

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