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[en] Basic patent technological solutions of butted units of nuclear energy technological plant for hydrogen and hydrogen-containing gases production by the method of methane vapour conversion using heat of high temperature helium-cooled reactors (HTGR) are considered. Various constructions of methane converters are suggested: converter with dense pipe packing, converter with cylindrical insertions, converter with direct-flow pipes, pipe converter with a water acket, converter with helium vessel air-cooling, non vessel variant of a pipe converter. The unitized and integral variants of arrangement of power technological plant equipment are discussed. It is shown that the development of the construction of helium cooled methane converter presents a complicated problem. Main difficulty consists in finding an optimal solution satisfying two contradictory requirements. On the one hand, a relatively small temperature gradient between the coolant and technological gas requires intensification of the heat of heat transfer process of helium side. From the other hand assuring of intensive heat exchange is limited by parameters of gas blower on differential pressure. Most prospective construction presents the one of conversion pipe of Feeld type

[en] The process of americium(6) reduction in the 4 mole/l NaOH solution at the 0 deg C temperature under azone influence is studied. The O₃ high concentration creates the O₃^- high content, the decomposition whereof is subjected to the law of the first-order rate. The O₃^- decomposition in accordance with the first-order reaction leads to origination of O₂^-, slightly reacting with Am⁶⁺. The O₃^- decomposition results in H₂O^-which reacts more slowly with O₃, therefore part of H₂O reduces Am⁶⁺. 7 refs

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[en] The possibility for americium (3) to oxidize in solution by water radiolysis products in the presence of hydrated electron (esub(aq)sup(-)) acceptors able to transform esub(aq)sup(-) to OH radicals has been studied. It is found that americium (3) oxidizes to americium (5) and americium (6) under γ-radiation in perchlorate solutions with pH=3-6 containing an excess of nitrous oxide, persulfate ions, or xenon trioxide. To elucidate the mechanism of radiation-chemical oxidation, a pulse radiolysis technique with optical detection of short-lived particles was used. It was found that the electron pulse effect on 9x10^-3 M americium (3) perchlorate solutions the 5x10^-4 - results in a broad band of short-lived absorption with a maximum at 340 nm. The absorption is due to the americium (4) ions. The rate constants are measured for americium (3) oxidation by OH radicals, americium (4) disproportionation, and americium (4) reduction by hydrogen peroxide and hydroperoxide radical. On the basis of the data obtained, a mechanism for americium (3) oxidation in γ-radiolysis is considered