Abstract: The presence of .beta.-lactam antibiotics in test material such as food, infusions, vaccines, blood for transfusion, body fluids, etc. may be determined by:seeding a nutrient medium with a .beta.-lactamase generating bacterium or spores thereof;applying a sample of said test material to a site on the so-called nutrient medium;then incubating the medium under conditions inducive to the generation of .beta.-lactamase by said bacteria; andassaying the .beta.-lactamase thus produced.

Abstract: The invention provides a process for the separation of a strong mineral acid from other species present in an aqueous solution and the recovery thereof. The process comprises the steps of: (a) bringing an aqueous solution containing the mineral acid to be separated into contact with a substantially immiscible extractant phase, whereupon the mineral acid to be separated selectively and reversibly transfers to the extractant phase; (b) separating the two phases; and (c) backwashing the extractant phase with an aqueous system to recover substantially all the mineral acid contained in the extractant phase. The special extractant phase used comprises a strong organic acid which acid is oil soluble and substantially water immiscible both in free and in salt form, an oil soluble amine which amine is substantially water insoluble both in free and in salt form and a carrier solvent for the organic acid and amine, the molar ratio of the organic acid to amine in the extractant phase being between about 0.5:2 and 2:0.5.

Abstract: The present invention relates to the production of chlorine and magnesium oxide. According to the process substantially anhydrous magnesium chloride, containing at least 95% MgCl.sub.2, is admixed with particulate magnesium oxide and contacted with gas comprising oxygen at a temperature from about 700.degree. C. to about 1100.degree. C. One of the advantages of the process according to the present invention is to utilize the exothermicity of the oxidation of the molten magnesium chloride, the reaction being self-sustained. According to a preferred embodiment, the particulate magnesium oxide is preheated at a temperature of above 720.degree. C. before it is admixed with the molten magnesium chloride and serves as the heat transfer agent for the subsequent oxidation of the magnesium chloride.The process may be carried out in a stack reactor or in a fluidized bed reactor. The oxidation is effected with substantially dry, pure oxygen or air.