Radioactive Ruthenium Research Articles

Radioactive Ruthenium and Manganese Isotopes in the Atmosphere

The movement of air masses between the stratosphere and the troposphere can be traced by studying the concentration and ratios of radioactive ruthenium and manganese injected into the atmosphere by nuclear bursts on the ground and in the air

Decontamination of Radioactive Ruthenium by Cellulose Derivative-Bentonite Flocculation (I)

Decontamination of Radioactive Ruthenium by Cellulose Derivative-Bentonite Flocculation (I)

The Electrodeposition of Ruthenium from a Ruthenium(III) and Ruthenium(IV) Solution and a Fission Products Solution

Abstract The electrodeposition of ruthenium from ruthenium chloride and ruthenium nitrosyl chloride solution has been studied and has been applied to the separation of the radioactive ruthenium contained in fission products. When the amount of the ruthenium deposited in a given time was plotted against the cathode potential, the curves for 1×10−7m solutions of chloride and nitrosyl chloride showed a maximum. The decrease in the electrodeposition at lower cathode potentials may be due to the anodic oxidation of ruthenium as well as to the evolution of hydrogen gas at the cathode. The rate of electrodeposition was found to depend on the material used as the cathode, and to be increased by an increase in the temperature and by the addition of the carrier platinum or ruthenium. A complete separation of radio-ruthenium from fission products resulted when electrolysis was carried out with a 0.1 m hydrochloric acid solution of fission products containing carrier ruthenium under the appopriate conditions mentioned in the text. The ruthenium electrodeposited on the platinum electrode was completely recovered into the solution by anodic oxidation.

THE UPTAKE OF RADIOACTIVE RUTHENIUM BY RAT LIVER NUCLEI.

Abstract The transfer of ruthenium between cytoplasm and nucleus in liver cells has been studied following the administration of 106 RU to rats, using the Lissapol nuclear isolation procedure. During the experimental period the isotope is lost from the cytoplasm approximately exponentially with a half-time of a00 h, but is taken up by the nuclei at a rate corresponding to a half-time of about 45 h; after 100–200 h there is a constant partition of the isotope between nucleus and cytoplasm. Mechanisms are considered which may account for the experimental results and it is tentatively concluded that the nuclear membrane has a restricted permeability to Ru in the chemical form in which it occurs in the cytoplasm, perhaps as a high molecular weight complex. The results accord with a permeability coefficient of the nuclear membrane to Ru of about 10 −9 cm sec −1 , which is similar for both inward and outward movement, suggesting that the permeation is passive and non-specific.

The Separation and Determination of Ruthenium in Fission Products by Liquid-Liquid Extraction with Pyridine

Abstract The present paper has described a method of separating, by liquid-liquid extraction with pyridine, radioactive ruthenium from fission products and technetium in an aqueous solution containing sodium hydroxide and hypochlorite. In the process, ruthenium in various ionic forms and various oxidation states is oxidized to perruthenate with the hypochlorite, and the perruthenate is transferred into pyridine from the aqueous solution. The partition coefficient of perruthenate was estimated for the carrierfree and the carrier-containing cases, as well as for the case where other fission products were present. Good separation of radioactive ruthenium from other fission products was achieved by this method, with a large decontamination factor. The results were examined by a γ-ray spectrum measured at each step of the extraction process.

The determination of traces of ruthenium in samples of platinum by neutron-activation analysis

A neutron-activation method has been developed for determining small amounts of ruthenium impurity in samples of platinum. The Harwell nuclear reactor BEPO has been used as the source of neutrons. The procedure depends on the chemical separation of radioactive ruthenium, with added ruthenium carrier, from irradiated samples and standards. Results are quoted for the ruthenium contents of a number of samples of platinum.

Analysis of Fission Product Mixtures

A procedure has been developed for the rapid, sequential separation of radioactive ruthenium, strontium, rare earths, zirconium--niobium, and cesium with recoveries greater than 97%, and individual decontamination factors greater than 1000. High decontamination factors are also obtained with radioactive iodine, cobalt, iron, chromium, and zinc. The precision of each analysis is within sintering time 4% at the 91% confidence limit. Designed for the examination of air-filters soil, sediment, vegetation, and aqueous samples, the analyses are made on 3N hydrochloric acid--0.1N hydrofluoric acid solution. With this solution, fission products are quantitatively leached from samples which cannot be easily dissolved. A complete analysis can be made in 16 hours, and a trained technician can analyze 40 samples per 40-hour week. By providing nearly quantitative recoveries and high precision, these procedures eliminate the necessity for gravimetric yield determinations without sacrificing specificity. Considerable application to other areas of radiochemistry is anticipated. (auth)