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Fission fragment (FF) angular distributions for 6,7 Li+235,238 U reactions and mass distributions for 6,7 Li+238 U reactions have been measured at energies near and above the Coulomb barrier. The angle integrated fission cross sections for 6 Li induced reactions at sub-barrier energies are found to be higher than 7 Li induced reactions possibly due to larger contribution of breakup induced fission in case of the former compared to the latter. The FF anisotropy for 6,7 Li+235 U was found to be smaller than 6,7 Li+238 U, manifesting the effect of target ground state spin. The statistical saddle point (SSP) model predictions were found to be consistent with the measured FF anisotropy for 6,7 Li+235 U, however they were under-estimated for 6,7 Li+238 U particularly at lower energies. Observation of larger FWHM of FF folding angle distribution and sharp increase in peak to valley ratio for FF mass distribution with the decrease in bombarding energy in 6,7 Li+238 U reactions confirms the presence of breakup induced fission.

A composite polymer membrane containing liquid anion exchanger and scintillator molecules was developed for preconcentration and quantitative determination of anionic radionuclides like pertechnetate and iodide ions. The radiation emitted by the radionuclides sorbed in the membrane lead to scintillation signals. This scintillating adsorptive membrane was prepared by immobilizing trioctylmethyl ammonium chloride (liquid anion-exchanger) along with 2,5-diphenyl oxazole (primary scintillator), and 4-bis(methylstyryl)benzene (wavelength shifter) in the plasticized polystyrene matrix. The anion selectivity of the membrane follows Hofmeister series i.e. hydrophobic anions are preferentially sorbed in the membrane matrix. It was observed that TcO4− ions were transferred quantitatively to the membrane matrix from equilibrating aqueous solutions having pH 2–8 and multicomponent feed solution like seawater. The amount of TcO4− ions preconcentrated in the membrane was directly quantified by counting the scintillations produced by β-particles in the membrane matrix. The scintillating membrane developed in the present work was optimized in terms of its scintillation efficiency, β-scintillation pulse height, anion-exchange capacity and reusability.

Angular distributions of projectile-like fragments (PLFs) have been measured in 19F+89Y reaction at Elab = 70, 85 and 100 MeV. From the center of mass angular distributions of PLFs, their cross sections have been deduced at these beam energies. Beam energy dependence of the cross sections of PLFs formed in quasi-elastic transfer reactions has been found to be significantly different from those formed in incomplete fusion (massive transfer) reactions. Experimental angular distributions were converted into the plots of the transfer probability versus distance of closest approach to deduce the slope parameter for different transfer channels. Comparison of the slope parameters suggested that the overlap of the projectile and the target nuclei increases with increasing beam energy for a given transfer channel and also with increasing mass transfer at a given beam energy.

Multiplicity of $\ensuremath{\gamma}$ rays emitted in complete and incomplete fusion of $84\phantom{\rule{0.3em}{0ex}}\text{MeV}$ $^{12}\mathrm{C}$ with $^{169}\mathrm{Tm}$ has been measured in coincidence with charged particles emitted at backward and forward angles. The angular momenta were deduced from the $\ensuremath{\gamma}$-ray multiplicity data after taking into account the angular momentum carried away by emitted particles. The results show that the mean angular momentum associated with incomplete fusion is slightly lower than ${l}_{\text{CR}}$ for complete fusion indicating deeper interpenetration of the target and projectile in incomplete fusion than usual peripheral collisions.