Abstract: The invention is a method of monitoring for the presence of certain constituents of food processing streams by measurement of fluorescence. The constituent monitored can be a fluorescing impurity of a food product, or the food product itself if such naturally fluoresces. Moreover, losses of the constituent to be monitored may be determined by concurrent measurement of fluorescence of a fluorescent material added to the food process stream. The method is applicable to the following food processing streams among others: meat, vegetable oil, sugar beet, sugar cane, grain, poultry, fruit and soybean processing streams. Upon determination of a variation of the fluorescing constituent to be measured, the food process can be adjusted accordingly.

Abstract: A method of improving the recovery of U.sub.3 O.sub.8 from circulating aqueous leach fluids used to extract uranium from its ores in underground uranium fields, which fields are made up of a series of injection and producing wells, which aqueous fluids are contaminated by suspended and dissolved inorganic iron compounds caused by the presence of anerobic and aerobic bacteria, which comprises treating such aqueous leach fluids with at least 0.1 ppm of a mixture of 75% of 5-chloro-2-methyl-4-isothiazolin-3-one and 25% 2-methyl-4-isothiazolin-3-one.