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Summary Plasticized anion-exchange polymer inclusion membranes (PIM) were prepared by physical immobilization of a liquid anion-exchanger trioctylmethylammonium chloride (Aliquat-336) into the polymer matrix of cellulose triacetate (CTA) plasticized with 2-nitrophenyl octyl ether (NPOE). The self-diffusion coefficients (D m) of I− ion in these PIMs were obtained by analysing the experimental 131I radiotracer exchange rates with an analytical solution of Fick's second law. The D m was found to increase exponentially as a function of volume fraction of liquid (plasticizer) in the membrane, which can be attributed to reduction of physical obstruction in diffusion path of the ions in CTA polymer matrix. The selectivity of PIMs towards different anions, with respect to I− ion, was obtained from a determination of mole fraction of I− ion (ratio of moles of I− ion to total ion-exchange sites) in the membrane as a function of mole fraction of I− ion in the equilibrating aqueous solution containing a competing X− ion (X− = F−/Cl−/Br−/NO3 −/ClO4 −). This study indicated that the PIM has preference for I− ion in the presence of Cl−, Br− and NO3 − ions in equilibrating solution, while ClO4 − ion are preferred over I− ion. The selectivity trend (ClO4 −>I−>NO3 −>Br−>Cl−>F−) in PIM was found to correspond with Hofmeister series.

Summary Absolute γ ray intensities in the decay of 194Tlg have been measured following the radiochemical separation of 194Pb produced in the reaction of 19F+181Ta. The (EC+β +) branching ratios in the decay of 194Tlg to various levels of 194Hg were deduced. Three new levels are introduced in the decay scheme. A precise value of half life of 194Pb (10.0±0.4 min) is reported.

SummaryFormation cross sections of about forty fission products have been determined using recoil catcher technique followed by off line gamma-ray spectrometry in7Li induced fission of232Th atElab= 41.9, 36.6 and 31.4 MeV. The measured data have been used to deduce charge and mass distributions. Mass distribution is found to be asymmetric at all the three energies. Cross sections of evaporation residues formed in both transfer reactions (232,233,234Pa) as well as in complete fusion (234Np), have also been measured. The measured evaporation residue cross sections and the decay probabilities of target like nuclei (233,234,235Pa) formed in the various transfer reactions, as calculated by PACE2, have been used to estimate the transfer induced fission cross sections. The data indicated that the magnitude of transfer induced fission is very small.