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Ammonium thiocyanate method can be used for the estimation of uranium in low grade ores after the preliminary isolation of uranium by ether extraction of the nitrate. A rapid method for the estimation of uranium in monazite concentrates is also described.

The kinetics of the hydrolysis of dichlorotriazinyl reactive dyes have been studied over a range of temperatures and pH values. The results have been examined in accordance with the generally accepted reaction scheme, and methods of calculating the separate rate constants are described. The activation energy of hydrolysis varies with temperature and this variation is thought to be due to changes in the activity coefficient or probability factor with temperature. The equilibrium between two forms of the dye does not have the characteristics of a simple acid-base equilibrium with respect to temperature, indicating that it may not arise from the ionisation of the imino bridging group, as has been generally supposed.

Crystal violet, a commercial dye, has been shown to be suitable in titrations with ceric sulphate. Its range of usefulness is great compared with tither indicators. Comparative studies on other indica­tors, viz., Xylene cyanol FF, N-phenylanthranilic acid and Rhodamine 6G are reported, extending their use to titration other than those originally recommended.

Separation of thorium from uranium by the classical oxalic acid method is not satisfactory in that the ignited oxide is slightly coloured. m-Nitrobenaoic acid and o-chlorobenzoic acid are shown to give highly satisfactory results in the presence of 50 to 60 times of uranium in a second precipitation.

Quadrivalent cerium gives a bright yellow colour with benzidine in hydrochloric acid solution. 0.03\(\gamma\) of the element can be detected on a spot-plate. Trivalent rare earths, Th, Cu, Be, Mg, alkaline earths, Zn. Al, Bi, \(UO_2^{++}\), Mn, Ni,\(NO_3^{'}\), \(PO_4^{''}\), CI', F’, MoO4", As3O4", in moderate amounts do not interfere ; but, vanadate and chromate cause interference even in small quantities. The reagent may also be adopted for the colorimetric estimation of cerium.

DURING the course of a systematic screening for antibiotics with antiviral activity, Streptomyces alanosinicus nov. sp. (ATCC 15710) was isolated from a Brazilian soil sample. This culture produced, under submerged conditions, a new antibiotic with antiviral and antitumour activity to which the name “alanosine” was given.

Thorium is adsorbed on a strongly basic akionexchange resin, Amberlite IRA-400 (sulfate form), from a sulfate solution of pH about 2.0. Under these conditions, tervalent cerium and other rare earths are adsorbed to only a slight extent. An ion-exchange method has been developed for the separation of thorium from these elements. The method has also been applied to the determination of thorium and rare earths in monazite concentrates. (auth)

Introduction Since the isolation and classification of Coxsackie viruses of Group B by Dalldorf 1 numerous investigations concerning the etiologic role of these agents as the cause of aseptic meningitis have been carried out both in the United States and abroad. In addition, during recent years evidence from different laboratories has also indicated that some specific types of ECHO viruses have been responsible for several outbreaks of aseptic meningitis. 2-10 During the years 1956 and 1957, 245 patient with a central nervous system (CNS) disease of presumed viral etiology were seen at the James Whitcomb Riley Hospital for Children. These patients came from areas throughout Indiana, and we were unaware of an outbreak of epidemic proportions occurring in any region during the course of the two-year study. The present study was undertaken in an attempt to recover viral agents from patients with a CNS involvement. Particular reference is made to

A volumetric method is described for the determination of uranium in presence of iron, phosphate, and nitrate. It is based on the oxidation of reduced uranium/sup IV/ with ferric sulfate and titration of the excess of ferric iron iodimetrm-cally. Osmium tetroxide has been found to be a suitable catalyst for the reaction. (auth)