A new powerful technique viz inductively coupled plasma-mass spectrometry (ICP-MS) has been utilized for the measurement of99Tc in the environmental samples. In this regard, when using anion exchange column for the separation of99Tc, significant quantities of Mo are also eluted from the resin along with the technetium. Various reagents (i.e., HCl, NaOH and HNO3) have been applied for the separation of Mo from the column prior to the Tc treatment. The result thus obtained are discussed.
A key aspect of the development of a procedure for the measurement of technetium in environmental samples is that each step should be optimized to achieve maximum recovery.99Tc and95mTc have been the tracers used for the determination of yields in steps involving anion exchange, leaching, ashing, solvent extraction, precipitation and evaporation. The results thus obtained are discussed.
Authors:Ihsanullah, J. Akhter, A. Rauf and M. Atta
A comprehensive radiochemical procedure for the measurement of gamma/beta activity of131I has been standarized by optimizing different steps. The procedure is mainly divided into three stages, i.e., (1) concentration
of iodine using anion exchange column followed by elution; (2) extraction of iodine into CCl4 and back extraction, and (3) precipitation as AgI. The percent chemical recovery and the lower limit of detection (LLD) were
found to be 75.5±5% and 0.014 mBq/ml, respectively.
Date samples were irradiated with different doses using a gamma-irradiator. Levels of moisture, protein, fibre and fats were
determined on monthly basis for 5 months. Generally, the moisture contents of control date samples packed in white polythene
decreased from 14.1±1.1 to 9.7±0.8% over a 5-month period while the irradiated samples were in the range of 10.4-11.2%, however,
no proper pattern of change was observed. After 5-month storage, the protein level of irradiated samples was reduced to 1.00-1.30%,
while the percent fibre levels were found to be in the range of 2.40-2.48. Similarly, the fat level decreases from 1.06±0.12
to 0.68±0.06 for control date sample while after 5-month the decrease in fat content was 0.45±0.04%, 0.44±0.04%, 0.44±0.05%,
0.42±0.05% and 0.40±0.04% for samples irradiated with 20, 50, 100, 200 and 300 krads, respectively.