Ammonium uranyl carbonate (AUC) based process of simultaneous partitioning and reconversion for uranium and plutonium in fast breeder reactors (FBRs) fuel reprocessing

Ammonium uranyl carbonate (AUC) based process of simultaneous partitioning and reconversion for uranium and plutonium is developed for the recovery of uranium and plutonium present in spent fuel of fast breeder reactors (FBRs). Effect of pH on the solubility of carbonates of uranium and plutonium in ammonium carbonate medium is studied. Effect of mole ratios of uranium and plutonium as a function of uranium and plutonium concentration at pH 8.0–8.5 for effective separation of uranium and plutonium to each other is studied. Feasibility of reconversion of plutonium in carbonate medium is also studied. The studies indicate that uranium is selectively precipitated as AUC at pH 8.0–8.5 by adding ammonium carbonate solution leaving plutonium in the filtrate. Plutonium in the filtrate after acidified with concentrated nitric acid could also be precipitated as carbonate at pH 6.5–7.0 by adding ammonium carbonate solution. A flow sheet is proposed and evaluated for partitioning and reconversion of uranium and plutonium simultaneously in the FBR fuel reprocessing.     

Sunburn Risk Among Children and Outdoor Workers in South Africa and Reunion Island Coastal Sites

To estimate potential sunburn risk for schoolchildren and outdoor workers, ground‐based ambient solar ultraviolet radiation (UVR) measurements were converted into possible child (5% of ambient solar UVR) and outdoor worker (20% of ambient solar UVR) solar UVR exposures by skin type and season for three coastal sites: Durban, Cape Point (South Africa) and Saint Denis (Reunion Island, France). Cumulative daily ambient solar UVR levels were relatively high at all sites, especially during summer, with maximum values of about 67, 57 and 74 Standard Erythemal Dose (SED) (1 SED = 100 J m^?2) at Durban, Cape Point and Saint Denis respectively. Sunburn risk was evident for both children and outdoor workers, especially those with skin types I and II (extremely to moderately sensitive) during summer, early autumn and/or late spring at all three sites. Although results need to be verified with real‐time, instantaneous and nonintegrated personal solar UVR measurements, this understanding of sunburn risk is useful for initiating the development skin cancer prevention and sun protection awareness campaigns in both countries.     

Cruising in ceramics—discovering new structures for all-solid-state batteries—fundamentals,materials, and performances

Energy storage research has drawn much attention recently due to increasing demand for carbon neutral electrical energy from renewable energy sources such as solar, wind, and hydrothermal. Various electrochemical energy storage and conversion technologies are being considered for their integration into smart grid systems, of which batteries seem to play a vital role due to their wide range of energy densities. In this review, we provide the current status and recent advances in solid-state (ceramic) electrolytes based on inorganic compounds for all-solid-state batteries. This paper is specifically focused on the fundamentals, materials, and performances of solid electrolytes in batteries. A wide spectrum of inorganic solid-state electrolytes is presented in terms of their chemical composition, crystal structure, and ion conduction mechanism. Furthermore, the advantages and main issues associated with different types of inorganic solid electrolytes, including β-alumina, NASICON and LISICON-type, perovskites, and garnet-type for all-solid-state batteries are presented. Among these solid electrolytes, Zr and Ta-based Li-stuffed garnets exhibit high Li-ion conductivity, electrochemical stability window (up to 6  V/Li at room temperature), and chemical stability against reaction with molten elemental Li. However, their stability under humidity and carbon dioxide should be improved to decrease the fabrication and operational costs.