Firing oxidizing

Hammond SE, Lagerquist CR, Mann JR. 1968. Americium and plutonium urine excretion following acute inhalation exposure to high-fired oxides. Am Ind Hyg Assoc J 29(2) 169-172. 

Fusion with anhydrous potassium fluoride in a platinum dish is undoubtedly the simplest, most effective and reliable method available for the complete dissolution of a wide variety of siliceous materials. The potassium fluoride cake can then be transposed in the same container to a pyrosulfate fusion with rapid and complete volatilisation of both hydrogen fluoride and silicon tetrafluoride [54]. Except for a small quantity of barium sulfate, the pyrosulfate cake will dissolve completely in dilute hydrochloric acid. The resulting pyrosulfate fusion is one of the simplest and most effective methods available for rapid, complete and dependable dissolution of nonsiliceous materials, particularly high-fired oxides. This fusion has the distinct advantage that the flux can be obtained by simply adding easily purified alkali metal sulfates to sulfuric acid, and the fusion can be carried out in either borosilicate flasks or platinum vessels with very little contamination from either reagents or containers. 

Hazard statement May cause or intensify fire oxidizer... 

Hazard statement May cause fire or explosion strong oxidizer May intensify fire oxidizer May intensify fire oxidizer... 

FUR BLACK 41867 (106-50-3) Combustible solid (flash jxrint 312°F /156 C). A strong reducing agent. Violent reaction with strong oxidizers. Incompatible with acids, organic anhydrides, isocyanates, aldehydes. Contact with red fuming nitric acid may cause fire. Oxidizes in air and light crystals become dark. 

The majority of the plutonium from weapons testing was injected initially into the stratosphere. The plutonium originally in the weapon which survived the explosion would have been formed into high-fired oxide which would be expected to remain insoluble as it returned to earth. Such insoluble particles would have sunk in a rather short time into the bottom sediments of lakes, rivers, and oceans or would become incorporated in soils below the surface layer. However, in most nuclear weapon explosions a considerable amount of plutonium is generated in the explosion via (n,7) reactions and subsequent a-decay of the product etc. In total, about two thirds of the plutonium released... 

Sanders C, Cannon W, Powers G. 1978. Lung carcinogenesis induced by inhaled high-fired oxides of beryllium and plutonium. Health Phys 35 193-199. 

Hazard statement May inicnsity fire oxidizer May iniensify lire oxidizer... 

A metal-firee oxidative spirocyclization of hydroxy methylacrylamide with 1,3-dicarbonyl compounds provides a range of spirooxindole 3,4-dihydro-2H-pyrans, in moderate to good yields. This strategy involves the formation of two C-C bonds and one C-O bond in one step (Scheme 7) (130L5254). 

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