Chemisorbed oxygen can be determined quantitatively by the measurement of gaseous N2/N2O liberated by treatment with hydrazine sulphate/hydroxylamine hydrochloride. The amount of chemisorbed oxygen depends on the degree of dispersion during irradiation and also the -dose. The chemisorption is enhanced in the presence of moisture. The partial reduction of the transition metal ion favours the formation of chemisorbed oxygen.
The exchange between chloramine-B and radioactive chlorine has been carried out in various media. The exchange is slow in strong acid and very weak acid media. Its maximum is at pH 3.3. There is no exchange in alkaline media. Optimum conditions for the preparation of radiochloramine-B with high specific activity are reported.
A new method for the continuous determination of H2O2 is described based on the catalytic decomposition of H2O2 by LaCoO3. Oxygen liberated is measured by a gas meauuring burette. -irradiated catalyst enhances the catalytic activity and decreases the time required for complete decomposition. The procedure is suitable for microdetermination of H2O2 in various food products.
Exchange studies with36Cl and Chloramine-B in strong acid medium revealed that the extent of exchange is less than that occurs at pH 3.3 indicating the formation of a new species of Chloramine-B which is not participating in the exchange reaction and this has been confirmed by conductometric titration of Chloramine-B with dilute solutions of H2SO4, HCl, HClO4 and CH3COOH.
Studies on the individual potentiometric determination of uranium and plutonium in a single aliquot have been initiated recently
in our laboratory. It was required to adapt the reported procedures (for the precise determination of uranium and plutonium
individually when present together in a sample) at various stages to make them suitable for the successive application of
the procedures to the same aliquot. Two alternative schemes are proposed in the present work. In the first, plutonium is determined
by HClO4 oxidation followed by the determination of total uranium and plutonium by Zn(Hg) reduction. In the second, plutonium is determined
by AgO oxidation following the determination of total uranium and plutonium by Zn(Hg) reduction. Amount of uranium is computed
in both cases from the difference of two determinations. Precision for the assay of plutonium and uranium was found to be
±0.25% and ±0.35%, respectively, at milligram levels.
Oxidation of cyclohexanol free from peroxide by carbon tetrachloride under the influence of gamma radiation was carried out both for air saturated and deareated systems. Large values for the formation of HCl are obtained. A kinetic expression consistent with experimental observations has been derived.
Volume reduction studies were carried out on low level radioactive plastic wastes containing polyethylene, PVC and neoprene
by melt densification. The optimized temperature for melting of plastics was between 170 and 180 °C. Based on laboratory scale
studies. Plant scale studies were planned and conducted. The volume reduction factors obtained were around 30, which was 6-10
times higher than that of the conventional compaction process. Thermogravimetry and infrared spectroscopy were used to investigate
the thermal and structural properties of the given materials. The effect of the presence of salts like potassium permanganate
and hydrazine sulphate on the thermal properties of the materials was also evaluated. Leaching studies were also performed
on melt-densified specimens in the laboratory. The average leach index was observed to be around 9, which was higher than
the minimum stipulated value.