The accumulation of thorium and uranium by various microorganisms from a solution containing both metals at pH 3.5 was examined. Among the tested species, a high accumulation ability for thorium was exhibited by strains of gram-positive bacteria, such as Arthrobacter nicotianae, Bacillus megaterium, B. subtilis, Micrococcus luteus, Rhodococcus erythropolis, and Streptomyces levoris. Though uranium was accumulated in small amounts by most of microorganisms, A. nicotianae, S. flavoviridis, and S. levoris had relatively high uranium accumulation abilities. In these high performance thorium- and uranium-accumulating microorganisms, S. levoris, which accumulated the largest amount of uranium from the solution containing only uranium at pH 3.5, accumulated about 300 μmol thorium and 133 μmol uranium per gram dry weight of microbial cells from a solution containing both thorium and uranium at pH 3.5. The amount and time course of the thorium accumulation were almost unaffected by the co-existing uranium, while those of uranium were strongly affected by the co-existing thorium. The effects of pH, the thorium and uranium concentrations, and time course on both metal accumulations were also evaluated by numerical formulas.

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A multi-dimensional Langevin equation is applied for the study of the multi-modal nuclear fission in actinide region. Two kinds of dissipation tensors, the wall-and-window formula and the wall formula, are used to investigate the dynamical effects of nuclear dissipation. The mass distribution and the total kinetic energy distribution of the fission fragments are calculated for ²⁶⁴Fm with these dissipation tensors. It is found that the dissipation tensor plays important roles in determining the fission paths. We obtain drastically different mass distributions by applying different models for nuclear friction.

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Temperature-dependent ⁵⁷Fe Mössbauer effect spectroscopy has been used to characterize the hyperfine and dynamical properties of the metal atom in two crystallographic forms of ferrocenium hexafluoroarsenate. The temperature dependence of the recoil-free fraction and the spin-lattice relaxation rates have been determined over the interval 89<T<300 K and shows a small difference between the two crystallographic forms. The sign of the quadrupole splitting parameter in the Fc⁺ cation has been elucidated in a transverse magnetic field experiment at room temperature.

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The neutron induced reaction cross-sections for target nuclei from ²⁷Al to ²⁰⁹Bi and incident neutron energies above 0.1 MeV have been calculated with the TALYS code and the modified ALICE code using different models for the description of the nuclear level density. Several thousand experimental points from EXFOR have been used for the comparison with these calculations. The obtained results give the possibility to find the best approaches for the cross-section calculation for nuclei in different mass ranges.

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Damped collisions of tranactinide nuclei (²³⁸U+²³⁸U, ²³²Th+²⁵⁰Cf, and ²³⁸U+²⁴⁸Cm) have been studied within the realistic model based on solution of multidimensional transport equations. Large charge and mass transfer was found in these reactions due to the inverse (anti-symmetrizing) quasi-fission process leading to formation of survived superheavy long-lived neutron-rich nuclei, suitable for subsequent chemical analysis. In many events lifetime of the composite system consisting of two touching nuclei (giant quasi-atoms) turns out to be rather long; sufficient for spontaneous positron formation from super-strong electric field, a fundamental QED process.

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The experimental results of the proton halo nuclei ²⁷P, as well as probably ²⁹S, and the neutron halo in excited states of the nuclei ¹²B and ¹³C are presented. The probability of the valence nucleon (s) being out of the binding potential have been extracted systematically from the relevant experimental data, and a new condition for nuclear halo occurrence is proposed. Based on our systematical study, we put forward our scaling laws of nuclear halo in terms of the analytical expressions of the expectation value for the operator r² in a finite square-well potential. In order to investigate the breakup effects of the weakly bound projectiles on fusion reactions and barrier distributions, the complete fusion cross sections of ⁶Li + ²⁰⁸Pb and the elastic and quasi-elastic excitation functions of ^{6, 7}Li, ⁹Be + ²⁰⁸Pb were measured and compared with the predictions of the coupled-channels model. The dynamical effects on fusion of neutron-rich nuclei at the energies around the Coulomb barrier are discussed in terms of the comparison of the measured fusion data of ⁴⁸Ca + ^{90, 96}Zr with the calculations of the improved quantum molecular dynamics model and coupled-channels theory.

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Mössbauer effect spectroscopy is one of the most important techniques for observing the dynamic phenomena of electronic states in solid. The Mössbauer spectra of mixed valence compounds show relaxation spectra if the electronic states are changed dynamically between Fe²⁺ and Fe³⁺. The dynamic electronic states of mixed valence compounds are discussed in connection with Mössbauer spectra of [Fe₂ (bpmp) (ppa) ₂]X₂ as examples. The absorption spectra and cyclic voltammograms of the compounds were measured. The electronic states of the mixed compounds are dependent on the species of their anions in the solid state.

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Radiochemical methods are of considerable significance in studies of low and intermediate energy nuclear reactions induced by light particles, particularly when low-yield and soft-radiation emitting products are involved. A brief description of the pertinent experimental techniques and nuclear model calculational codes is given. The data related to nucleon emission, complex particle emission and formation of isomeric states are reviewed. The nuclear model calculations can reproduce the nucleon emission cross sections fairly well. In the case of isomeric cross sections the calculations demand a careful choice of the input parameters, especially regarding the level structure of the product nucleus. The emission of complex particles is as yet not described well by the theory; the radiochemically determined data serve to develop systematic trends which qualitatively enhance our knowledge on those processes.

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An overview of present experimental investigation of superheavy elements is given. The data are compared with theoretical descriptions. Results are reported from an experiment to confirm production of element 112 isotopes in irradiation of ²³⁸UF₄ with ⁴⁸Ca. One spontaneous fission event was measured, which agrees with three events of previously measured data which had been assigned to the decay of ²⁸³112. However, more experimental work is needed in order to obtain an independent and unambiguous confirmation of previous results.

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The particle size distributions of radioactive nuclides formed in accelerator beam line tunnels were measured by using a diffusion battery and were found to be log-normal with a geometric mean radius of about 28 nm. The radioactive aerosol formation was well explained by a simple physical adsorption of radioactive nuclides to the ambient non-radioactive aerosols. The fractions of aerosol and gaseous components were measured for individual nuclides formed in the air of a high-energy accelerator tunnel. The formation of these ¹¹C and ¹³N species was explained by their hot-atom reactions and subsequent chemical reactions.

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The recent several decades have seen the spectacular advances in a new area at the junction of elementary particle physics and chemistry, the so called chemistry of new atoms in which either electron is replaced by another negative particle or a proton by another positive particle. The area of research does not confine itself to chemical studies alone. External influences on the properties of new atoms provide useful, sometimes unique information about the structure of solids. In this review, we survey briefly properties of the new atoms and illustrate the last statement on example of positronium, the simplest hydrogen-like atom, where pick-off annihilation process gives valuable information on the free volume nanostructure of solids.

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