[en] It is shown by some examples how chemistry allowed the production of materials required by nuclear industry (graphite, zirconium, uranium, sodium, isotopes, TBP, glass for radioactive wastes, corrosion resistant alloys). Conversely these materials have now applications in various fields: microelectronics, medicine..

[en] Some applications of radionuclides, by-products of research reactors, are recalled. Then the importance of chemistry in the exploitation of fluid circuits of different types of nuclear reactors are examined. These examples and chemical problems to solve for fusion reactor studies are used to justify the need for chemistry training to take nuclear industry into account

[en] New extractants for lanthanides, actinides, alcohols, iron, ash, etc. were studied in the Separations Science program. Topics studied in the Fuel Cycle Chemistry program included Np and Pu photochemistry, Raman studies of actinides, solvent extraction of Ru, Tc, and Re by TBP, and Mo- and Zr-containing precipitates in high-level waste and fuel reprocessing solutions. Chemical Engineering research included development of a continuous annular chromatograh, granular electrofiltration for removing small particles, high-temperature slagging for extracting copper, CH₄ purification, and sedimentation. Recovery of alumina from fly ash by dissolution was studied. Thermodynamics and compatibility of Th and U carbides with clad alloys were studied. It was found that yttrium sorbents can remove tritium from lithium

[en] The purpose of this paper is first briefly to review the basic chemistry underlying the processes used on an industrial scale for the manufacture of fuel elements for thermal nuclear power reactors and then to consider in more detail the chemistry involved in the reprocessing of this fuel after irradiation, paying particular attention to developments which have been made to allow the newer enriched oxide fuels to be processed. Section headings are: nuclear fuel manufacture (U metal fuel; UO₂ ceramic fuel); nuclear fuel reprocessing; irradiated fuel dissolution; solvent extraction chemistry (chemistry and kinetics of Pu reduction; the behaviour of Np and Tc); treatment of highly active raffinates (evaporation and storage of highly active liquors; highly active waste vitrification; thermal decomposition of wastes). (U.K.)

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[en] The development of radiochemical techniques for rapidly separating fission products for yield measurements will be discussed. Some results of the measurements will be presented and compared with results from other types of yield measurements and with systematic trends in the yields deduced from empirical models

[en] Radioactive atoms formed in nuclear reactions provide excellent tracer species for investigations of chemical reaction mechanisms, including both hot and moderated thermal reactions. The addition of thermal ³⁸Cl to haloolefins (e.g. CH₂=CHBr) is only weakly anti-Markownikoff (Reaction at the less-substituted carbon to form CH₂³⁸ClCHBr), but isomerization of the initial radicals is frequently observed. Thermal ¹⁸F atom addition to the C2 carbon of substituted propenes (RCH₂CH=CH₂) creates excited radicals which decompose to form CH₂=CH¹⁸F + RCH₂. The rate constant for radical decomposition decreases with increasing R for olefins from propene to heptene, but not when R contains a heavy atom such as (CH₂=CHCH₂)₃Sn or (CH₂=CHCH₂)₃Ge which is believed to block intramolecular energy transfer. Decomposition has been observed with the addition of thermal T atoms to metal-allyls, in apparent disagreement with comparable experiments with thermal H atoms. Energetic substitution reactions have been observed for ³H, ¹⁸F and ³⁸Cl with many gaseous organic compounds; some of these substitution reactions can also take place with thermal atoms

[en] New states in the positive parity yrast bands of ⁷⁴Se and ⁷⁷Kr have been observed with the reactions ⁵²Cr(²⁸Si,α2p)⁷⁴Se and ⁵²Cr (²⁸Si,2pn)⁷⁷Kr at 98 MeV. The target consisted of approximately 1 mg/cm² natural chromium (84% ⁵²Cr abundance) evaporated on a thick lead backing. The new states extend the known level scheme of ⁷⁴Se up to I^π = (22⁺) and most of the transitions in the other previously reported bands have been seen. For the states I^π ≥ 6⁺ the spectrum shows a relatively constant moment of inertia parameter (h²/2Θ) = 27.8 ± 0.5 keV. Excited positive parity states up to spin (41/2) have been observed in ⁷⁷Kr. ΔI = 1 transitions have been identified throughout the positive parity band. The energies, mixing ratios and B(M1) transition rates for these transitions alternate in size as the spin increases. A cranked shell model analysis was performed along with Strutinsky-Bogolyubov cranking calculations. The observed decrease in the signature splitting of the νg_9/2 band has been attributed to a band crossing due to an aligning pair of g_9/2 protons. Prolate quadrupole deformations of β₂ = 0.34 for the ground band and β₂ = 0.26 for the first excited band are predicted. This band crossing is associated with a shape change caused by the polarization effect of aligned quasiparticles