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The elemental composition and phase analysis of fly ash collected from a thermal power plant in West Bengal, India was evaluated using X-ray diffraction (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM–EDX), energy dispersive X-ray fluorescence (ED-XRF) spectrometry, neutron activation analysis (NAA). Further, the particle size and surface morphology of the particles were also examined. Zeolite-A was prepared by fusion followed by hydrothermal synthesis method and its formation was confirmed by XRD. Based on the composition analysis, the Si/Al ratio was found to be 1.51, which is a good proportion to synthesise low silica zeolites. [ABSTRACT FROM AUTHOR]

Characterization studies were carried out for the freshly installed dry tubes (DT-1 and DT-2) in KAMINI reactor. The maximum gold equivalent neutron flux at 20 kW for DT-1 and DT-2 were found to be (1.02 ± 0.02)E+10 cm−2 s−1 at 368 and (4.90 ± 0.30)E+7 cm−2 s−1 at 300 mm respectively. The sub-cadmium to epithermal neutron flux ratio (f) and epithermal neutron flux shape factor (α) were found to be 144 ± 7 and − 0.289 ± 0.010 respectively at this position for DT-1 alone. These parameters were validated by analyzing the IAEA standard (SL-1) and applied to analyze jarosite samples using k0-based internal monostandard neutron activation analysis. [ABSTRACT FROM AUTHOR]

Coal fly ash (CFA) is an important secondary source for the recovery of gallium (Ga) which has a high potential for its wide applications in many strategic fields such as cellular communications and direct broadcast satellite. Various coal fly and bottom ash samples obtained from thermal power plants located in different parts of India were investigated for their gallium content using NAA and EDXRF techniques. The concentration of gallium in NIST SRM 1633b CFA is not available in NIST certificate and hence was established using k 0 based IM-NAA method along with the other certified elements like As, Ce, Co, Eu, Fe, K etc. In addition, the gallium concentration in the NIST SRM was also obtained by relative NAA using Ga 2 O 3 as a standard towards the validation of IM-NAA. Using the NIST SRM, the gallium content in the ash samples of Bituminous coal collected from South Central and Eastern India was found to be from 17.2 to 47.9 mg/kg whereas the same was 6.3-33.3 mg/kg for the ash samples of Lignite coal collected from the South-Central India and Western India. The gallium concentrations obtained by NAA in coal ash samples were compared with another non-destructive assay technique, i.e. EDXRF and the results are found to be in good agreement. These samples were proved to be a potential secondary source of gallium, available in India., (Copyright © 2022. Published by Elsevier Ltd.)