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A general formula has been developed for the fluctuations in the X-ray absorption coefficients observed on the high-energy side of an absorption edge, on the assumption that the ejected photoelectron undergoes inelastic collisions in the vicinity of the absorbing atom only. For the intermediate energy range 50-250 eV the directional dependence of the scattering event has been taken into account by replacing the atoms at a given distance from the absorbing atom by a continuous distribution on a spherical shell of the same radius. The positions of the absorption maxima and minima have been calculated for copper and compared with experiment. Reasonable agreement has been found between the experimental results and the present calculations.

X-ray LIII absorption edges of lead and bismuth in several of their inorganic compounds have been investigated. It is found that the shift, in general, is towards the high-energy side of the absorption edge in all the compounds except lead bromide. The results show that the shifts increase with the increase in valency. These results, however, do not show any regular variation in the shift with changed ionic character of the bond in the various compounds studied

Fifty-six children with pyrexia were subjected to the NBT spontaneous qualitative test. The test was positive in pyrexia due to systemic bacterial infection with the exception of tuberculosis, and in malaria. The test was negative in pyrexia associated with viral fevers and non-infective fevers. The practical use of the NBT test in the differential diagnosis of febrile disorders in children is confirmed. The technical method of performing the NBT test was modified to suit the less well equipped laboratories at the district level as well as other institutions.

X-ray K-absorption edge of selenium has been studied in zinc selenide and cadmium selenide. It has been found that the edge shifts towards high energy side in both the compounds. This observed shift (2.1 eV in ZnSe and 5.2 eV CdSe) has been used to explain the greatly increased strength of the chemical bonding in these compounds.