STUDY OF DISPERSANT AGENTS FOR THORIUM OXIDE

S>A preliminary study of dispersing agents for thorium oxide was completed and several of the dispersants have possible uses. Also many of the industrial dispersing agents tested are not usable with thorium oxide due to induced behavior causing balling and caking. The effects of nitric acid concentration were observed to also effect each dispersing agent. (auth

DETERMINATION OF Lisup6sup 6 IN AQUEOUS SOLUTION BY NEUTRON ACTIVATION ANALYSIS

A method for determining the concentration of Li/sup 6/ in aqueous solution was tested using the nuclear reactions Li/sup 6/(n, alpha )H and O/sup 16/(H/sup 3/,n)F/sup 18/. Annihilation gamma radiation of induced 1.87-hr F/ sup 18/ radioactivity was counted with a welltype scintillation counter, and the radioactivity per millimole of lithium was found to be independent of lithium concentration below about 0.2 moles/liter. The sensitivity limit for detecting lithium is less than 0.1 micromole (0.0075 micromole Li/sup 6/). (auth

The Radiochemistry of Selenium

A review of the nuclear and chemical features of selenium, a discussion of problems of sample dissolution and counting techniques, and a collection of radiochemical procedures for the element as found in the literature are presented. (94 references) (M.C.G.

The Radiochemistry of Iridium

The general and analytical chemistry of Ir are reviewed and applications to the radiochemistry of Ir are discussed. Topics covered include dissolution of samples containing Ir, counting techniques for radioactive Ir isotopes, radiochemical procedures for Ir radionuclides, and safety practices. A list is included of the radioactive nuclides of Ir. 106 references. (C.H.

The Radiochemistry of Cobalt

The radiochemistry of cobalt is discussed. Included are a review of the nuclear and chemical features of cobalt, a discussion of problems of dissolution of a sample and counting techniques, and a collection of radiochemical procedures for the element as found in the literature. (M.C.G.

DETERMINATION OF OXYGEN IN OXIDE FILMS BY NEUTRON ACTIVATION ANALYSIS

Preliminary experiments were conducted to evaluate the use of the nuclear reactions Li/sup 6/ (n, alpha )H/sup 3/ and O/sup 16/(H/sup 3/,n) F/sup 18/ to determine the thickness of oxide films on metals. Sheets of thin paper and of aluminum, imbedded in powdered LiF, were irradiated with pile neutrons at a flux of 6 x 10/sup 11/ n/cm/sup 2//sec and counted with an end-window proportional counter. A saturation activity of 1.87 hr F/sup 18/ of 150 dis/min per microgram of oxygen was observed in the paper, but radioactivity due to impurities masked F/sup 18/ in the aluminum. It is concluded that a 1 A (0.01 mu gm/cm/sup 2/) oxide film thickness may be measured by a neutron irradiation at a flux of 10/sup 14/ n/cm/sup 2//sec but chemical separation of induced radioactivity from the bulk metal is essential. (auth