No abstract available

[en] A description is given of an apparatus for growing single crystals of metallic cobalt by the czochralski method. The procedure adopted to obtain hexagonal single crystals of linear size larger than 1 cm is illustrated

No abstract available

[en] A ⁵⁹Co target was irradiated with 47 MeV ⁷Li, which produced NCA ⁶²Zn in the target matrix. NCA ⁶²Zn was separated from the target matrix by adsorption on calcium alginate beads kept in HNO₃ solutions of different pH values (1-6). The optimum separation condition was achieved at pH 5, where ∼83% NCA ⁶²Zn was adsorbed on the alginate beads along with some contamination from the bulk Co. The complete separation of ⁶²Zn from the bulk was achieved on desorbing Co from the beads with 0.1 M NaNO₂. The remaining ⁶²Zn was separated on re-adsorption under the same condition. (author)

[en] The activation method is used to measure differential cross-sections for the ⁵⁹Co(n,α)⁵⁶Mn reaction in the threshold region from 5.07 to 9.98 MeV. The results from this investigation, along with other recent experimental data from the literature, are employed to adjust the ENDF/B-V evaluation for this reaction by means of the generalized least-squares method, thereby producing a new evaluation which better reflects contemporary knowledge of the cross-section over the energy range which has been explicitly addressed by differential experiments (5.5-18 MeV). Nuclear-model calculations are also performed in order to develop a physically reasonable differential cross-section shape for extrapolation toward threshold so that this evaluation spans the entire energy range required for ENDF/B (threshold-20 MeV). Attention is given in this work to covariances, in both the measurement and evaluation processes. Finally, the resulting differential evaluation is employed in calculations of fission-spectrum averaged cross-sections which are then compared with corresponding measured values from the literature. (author)

[en] Short communication

[en] The ANISN code, which is more exact than 'blacken-theory', is used to calculate the thickness of cobalt targets of 'sandwich' type structure in HFETR core. Result shows: there is a wide radioactivity peak when the cobalt thickness is between 2.5 mm and 3.0 mm, the optimal thickness of maximum's radioactivity is about 2.9 mm

[en] Inclusive measurements of the charged light particles emitted from the reaction ¹⁹F+⁵⁹Co at 65 MeV incident beam energy have been done. The experimental data, obtained at the IPNE Bucharest Van de Graaff FN-Tandem accelerator, have revealed the presence at forward angles, of non-compound reaction modes beside the compound nucleus mechanism. The gamma-ray energy spectra, measured in the same experiments, have allowed the identification of the reaction channels. (authors)

[en] The quantum-mechanical theory of pre-equilibrium reactions due to Feshbach, Kerman and Koonin is reviewed and applied to the analysis of reactions of neutrons on /sup 59/Co. The semi-classical and quantum-mechanical theories of pre-equilibrium reactions are compared, and their future development discussed

[en] Published in summary form only