Electronic spectra are reported for 1-indanyl, 1-tetralyl, and 1-indenyl radicals generated photolytically or radiolytically in rigid matrices; the former two radicals show spectral features similar to those of benzyl radical, whereas the latter radical has a different spectrum because of its non-alternant π electron system.

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LiNO, addition to the cement solidified miscellaneous wastes has been proposed for preventing hydrogen ges generation caused by the corrosion of aluminum materials contained in the wastes. To determine an additive among alkaline metal ions, galvanic current was measured in 0.1 M alkaline metal hydroxide solution between aluminum and platinum electrodes. The volume of hydrogen gas generated from an aluminum specimen was measured in a KOH solution with LiN03, LiCI, LiBr, Li2C03 or Li2S04 to decide the best additive. Applicability of the chosen additive to cement was confirmed by hydrogen gas generation measurement from an aluminum specimen in cement paste. The prevention mechanism was analyzed by X-ray diffraction, SEM and SIMS. The current measured in LiOH solution decreased with time, then reached 0 pA/mmz, while the current was detected in other alkaline metal hydroxide solutions. The least volume of hydrogen gas generation was measured in a KOH solution with LiN03. The volume of generated hydrogen gas in cement paste with LiN03 was less than 10% of that without LiNO,. The results of analyses showed that a n insoluble film of LiH(A10z)z5Hz0 was formed on the aluminum surface. 'These results suggested that LiNOs addition to cement is effective to prevent hydrogn gas generation by formation of the insoluble film on aluminum.

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To clarify various kinds of precipitates formation behavior in high level liquid waste (HLLW) from the nuclear fuel reprocessing process, undissolved materials generated in concentration step under vacuum evaporation and aging step at various temperatures and nitric acid concentrations using simulated HLLW solution were closely investigated.Three kinds of material, mixed crystalline salt of barium and strontium (Bao.&Sro.&(NO,h), phosphomolybdic acid (P 2 0 5 ·24Mo0 3 ·7H20), and zirconium molybdate (Zr(0Hh·Mo20,· (H20 h) were obtained as the precipitates in the simulated solution. Mixed crystalline salt and phosphomolybdic acid were formed during concentration process. Yield of the former depended on solubility of barium nitrate in nitric acid, so the precipitate was redissolved at concentration below 6 M HN0 3 because of a large solubility at low concentration of HNO,. The yield of the latter depended on concentration factor of HLLW, but the precipitate was not redissolved at concentration of 2-10M HN0 3 in HLLW.On the other hand, the formation yield of zirconium molybdate which was formed during aging step was effected by both temperature and HN0 3 concentration and increased at high temperature and low concentration of HNO,.