Pi mesons are an important part of the interactions among strongly-interacting particles, and their reactions with complex nuclei involve reactions with a wide range of interactions and time scales, with the slowest being the familiar fission process. Decades of effort have produced a wide range of fission data with stopped and energetic charged beams, both positive and negative. These results are the result of many uncoordinated studies, but in total can give a very good view of pion-induced fission. This review will compare and combine the measurements, with comparisons to a range of theoretical expectations. It is found that the nature of fission induced by pi mesons is not significantly different from fission induced by other energetic particles, in spite of the special features of the mesonic beam. This specific arena of nuclear science may now be considered complete.

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Emission Mössbauer spectroscopy is about three orders of magnitude more sensitive than the conventional absorption mode, thereby allowing parts per million substitution of ⁵⁷Co at the Cu or Mn active site without perturbing the finely-tuned material. ⁵⁷Co faithfully probes the behavior of Cu-based high temperature superconductors and mixed valence magnetoresistive manganites. The application of emission Mössbauer spectroscopy to biological systems is also highlighted.

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SnO₂ (3 % Sb) films were implanted with 5×10^{16 57}Fe ions/cm² at the substrate temperature of 500°C, and annealed at temperatures between 400°C and 800°C. These films were characterized by depth selective conversion electron Mössbauer spectroscopy (DCEMS) using a back scattered type of a gas proportional counter, and measured by a Kerr effect magnetometer. Kerr effect measurements of the SnO₂ films showed ferromagnetism at room temperature. The Mössbauer spectra of the as-implanted films consisted of paramagnetic doublets of Fe³⁺ and Fe²⁺ species and two broad sextets, which showed site A and site B of fine grain magnetite. The Kerr rotation angles increased step by step with post-annealing up to 700°C. This phenomenon was attributed mainly to ferromagnetic maghemite produced by post-annealing. It was found from DCEMS analysis that the maghemite with relatively large grains exists more in top layer than deep layer.

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The extraction behavior of rutherfordium (Rf) onto trioctylphosphine oxide (TOPO) resin from 2.0 – 7.0 M HCl solutions was studied together with that of the homologues Zr and Hf. The extraction yields of Rf, Zr, and Hf increased with an increase of HCl concentration, and the sequence of their extraction was Zr > Hf ≥ Rf. It is suggested that the stability of the RfCl₄·2(TOPO) complex is lower than that of the corresponding species of the homologues.

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