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To assess contamination levels of the heavy metals, concentrations of Sc, Cr, Fe, Co and Zn in surface soils at various locations of southern part of Bangladesh were determined by Instrumental Neutron Activation Analysis (INAA) technique. In this study, concentrations of the Sc, Cr, Fe, Co and Zn elements in surface soil were found in the range of 2.56-16.7 µg/g, 12.9-112 µg/g, 6911-48642 µg/g, 2.59-22.7 µg/g and 37.7-322 µg/g, respectively. The measured concentrations were compared with average concentration of worldwide soil and observed that most of the samples contain much higher concentration of heavy metals except Cr and Fe. Analysis based on soil utilization type showed that the samples collected from roadside and residential area experienced much higher metal contamination than open area. A significant correlation was observed between Cr-Fe, Cr-Co, Cr-Sc, Fe-Co, Fe-Sc and Co-Sc. [ABSTRACT FROM AUTHOR]

The basic parameters related to radiochemical separation of iodine from tellurium and antimony by anion-exchange chromatography using the resin Amberlyst A26 were studied. The separation yield of 124I amounted to 96% and the decontamination factor from 121Te and 122Sb was > 104. The method was applied to the production of 124I via the 123Sb( α, 3 n) reaction. In an irradiation of 110 mg of natSb2O3 (thickness ∼ 0.08 g/cm2) with 38 MeV α-particles at 1.2 μA beam current for 4 h, corresponding to the beam energy range of E α = 37 → 27 MeV, the batch yield of 124I obtained was 12.42 MBq and the 125I and 126I impurities amounted to 3.8% and 0.7%, respectively. The experimental batch yield of 124I amounted to 80% of the theoretically calculated value but the level of the radionuclidic impurities were in agreement with the theoretical values. About 96% of the radioiodine was in the form of iodide and the inactive impurities (Te, Sb, Sn) were below the permissible level. Due to the relatively high level of radionuclidic impurity the 124I produced would possibly be useful only for restricted local consumption or for animal experiments. [ABSTRACT FROM AUTHOR]

The cross sections of the reaction 98Mo( n, γ)99Mo at neutron energies of 0.0334 eV and 0.0536 eV were measured for the first time using the activation technique, and the resulting values of 116 ± 7 mb and 91 ± 5 mb, respectively, are in good agreement with the JENDL-4 and ENDF/B-VII data files. Those measured values were extrapolated to the energy 0.0253 eV assuming 1/v dependence in the thermal region and the results were compared with the integrally measured values reported in the literature. The new data are thus useful to check the evaluated excitation function. [ABSTRACT FROM AUTHOR]

The neutron capture cross section for the 152Sm( n, γ)153Sm reaction at an energy of 0.0334 eV was measured for the first time using monochromatic neutrons of a powder diffractometer at the TRIGA Mark II nuclear reactor at Dhaka, Bangladesh. The 197Au( n, γ)198Au reaction was used to monitor the neutron beam intensity. The radioactivity of the products was determined via high resolution γ-ray spectrometry. The obtained cross section value is 184 ± 22 b, which is consistent with both the ENDF/B-VII and TENDL-2012 data libraries. The measured value at 0.0334 eV and the previous data at 0.0536 eV confirm the reliability of the data in the above libraries. [ABSTRACT FROM AUTHOR]

Integral cross sections of the 64Zn( n, p)64Cu and 67Zn( n, p)67Cu reactions were measured for the fast neutron spectrum of TRIGA Mark-II reactor at Savar, Dhaka, Bangladesh. A clean radiochemical separation was performed to isolate the copper radionuclides from the target element zinc. The radioactivities produced in the irradiation were measured by HPGe γ-ray spectroscopy. The neutron flux over the energy range 0.5-20 MeV was determined using the 58Ni( n, p)58Co monitor reaction. The measured results amount to 28.9 ± 2.0 mb and 0.84 ± 0.07 mb for the formation of 64Cu and 67Cu, respectively. These values are slightly lower than the respective values for a pure fission spectrum. The present results were compared with data calculated using the neutron spectral distribution and the recently critically analysed excitation function of each reaction given in the literature. The good agreement validates the reliability of those excitation functions. The feasibility of simultaneous production of 64Cu and 67Cu with fast neutrons is discussed. [ABSTRACT FROM AUTHOR]