Multi-modal nuclear fission of fermium isotopes at low excitation energy is dynamically investigated. The multidimensional Langevin equation is used for the dynamical calculation. We use the potential energy taking account of the microscopic energy which depends on the excitation energy. We calculate the mass and the total kinetic energy (TKE) distributions of the fission fragments for ²⁶⁴Fm. The deformation of the fission fragments at the scission plays an important role in classifying the nuclear fission modes. We show that there exist following three types for the scission configuration classified by the shape of the fission fragments: mass-symmetric compact configuration, mass-asymmetric configuration, and mass-symmetric elongated configuration. We calculate the average mass number and the average TKE for each configuration. We also study the isotope dependence of the mass distribution of the fission fragments from three fermium isotopes.

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Ion exchange of cerium on uranium antimonate (USb) from nitric acid medium was studied. The distribution coefficient of ∼19, 000 mL/g was obtained for ion exchange of cerium in 0.1 M nitric acid and it decreased with increase in the concentration of nitric acid. Rapid ion exchange of cerium in the initial stages of equilibration followed by the establishment of equilibrium occurs after one hour. Ion exchange data were fitted into both Langmuir and Freundlich adsorption models using non-linear regression. The enthalpy change accompanied by ion exchange of cerium was determined by the temperature variation method. The performance of the ion exchanger under dynamic condition was assessed by following a breakthrough (BT) curve and the BT curve was fitted using Thomas equation.

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Investigations on the removal of iron from phosphoric acid by precipitation method were carried out using pure and commercial sodium sulphides. The effect of iron on the extraction of uranium from phosphoric acid using a mixture of di-2-ethylhexyl phosphoric acid (HDEHP) and a commercial trioctyl phosphine oxide (CYANEX 921) in kerosene has been investigated. The influence of HDEHP, CYANEX 921, Fe (III), sulphide concentrations as well as temperature on the extraction of U (VI) from phosphoric acid were separately investigated. The results are compared and optimum conditions for monitoring the effect of iron and sulphide on the extraction of uranium from phosphoric acid are proposed.

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An iron (III) compound [Fe (thpu) (Hthpu) ] has exhibited spin transition behavior (T_1/2↓=225 K and T_1/2↓=239 K) with a thermal hysteresis loop (ΔT = 14 K). When the sample has been illuminated at 5 K, an increase in the dc susceptibility was observed. This suggests that the transition from the low-spin state to the high-spin state can be induced by illumination.

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The study of transition metal based materials displaying colossal magnetoresistance (CMR) is one of today's most exciting fields of research mainly due to the scientific challenge of finding the possibly common root (if that exists) of the CMR effect in the various materials. In this review we present novel results obtained by ⁵⁷Fe Mössbauer studies done on three different types of CMR materials, namely the cobalt based perovskites La_0.8Sr_0.2Fe_xCo_1-x, O_3-d, the Sr₂FeMoO₆ double perovskite, and copper containing chalcogenide spinels (Fe_1-xCu_xCr₂S₄).

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This review focuses on recent fruitful findings of dependence of sputtering phenomena on solid-state property and secondary particle species in the field of interaction of MeV-energy heavy ions with matter. Emission mechanism of singly charged ions from non-insulating targets is explained by the Sigmund-Thompson linear cascade model combined with increase of ionization probability by transient electronic excitation. However, emission mechanism of multiply charged ions differs from that of singly charged ions, and can be explained by a combined mechanism of simultaneous recoiling and ionization by the projectile and the Coulomb repulsion by a short-lived ionized track region. Large cluster ions are produced from non-metallic targets. Mostly clusters are emitted directly from solid surface. However, in the case of Al₂O₃, they are produced by coagulation of small molecules in a selvage region near the surface.

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