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- Author or Editor: R. Stella x
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Abstract
Radioanalytical techniques are used in this work to investigate the extraction behaviour with TBP of rhodium (III) chloride solutions to which a large excess of iodide is added. Extraction yields and distribution coefficients are determined as a function of HClO4 or H2SO4 content in the aqueous phase. Rhodium-stripping from the organic phase with ammonia solutions is also tested.
Abstract
A description is given of the preparation and chemical properties of copper(II) hexacyanoferrate (II) and (III). The first is well known and already used for rapid determination of137Cs in a wide variety of matrices, but the survey reveals that copper(II) hexacyanoferrate(III) is preferable as long as adsorption capacity is concerned. Thermal stability, reactions in acid media and competitive adsorption of K+ and NH 4 + ions are discussed for both adsorbers.
Abstract
A new inorganic exchanger consisting of the normal copper chromate (CUCR) was prepared and studied: its application to radiochemical separations was explored after batchwise measuring the distribution coefficients of several elements. Radiostrontium isolation from fission products was performed by combined use of CUCR and PRTD, a new form of tin dioxide previously investigated.
Abstract
A novel type of tin oxide and its cation exchange properties are described. The preparation of the oxide is rather unusual and consists in the precipitation of SnO·xH2O in the presence of sodium nitroprusside and its digestion in the presence of sodium nitrite. The final product is a partially reduced tin dioxide (PRTD) with one out of eight atoms of metal in the lower oxidation state of +2 and a great part of the bound water hydrogen replaced by sodium. Usual applications of commercially available tin dioxide exchangers can be extended to PRTD with remarkable advantages.
Abstract
A procedure for90Sr determination in calcium rich samples is presented. It is based on the precipitation of calcium oxalate in homogeneous solution and under controlled conditions to minimize the coprecipitation of strontium. The latter is subsequently separated as carbonate and radiochemical purification is completed by ion exchange chromatography on two inorganic exchangers: PRTD (partially reduced tin dioxide) and CUCR (copper chromate). The procedure was applied to environmental samples such as ashed sediment, fish and vegetable and results are reported.
Abstract
Multielemental analysis of atmospheric particulates collected on filter paper has been investigated using different radioisotopic exciting sources. Quantitative determinations for zinc and lead during a one year period are reported.
Abstract
The following elements: Cr, Zn, Co, Cd, Mn, V are determined in a sample of NBS (spinach) which has to be certified as a new standard. Both neutron activation analysis and atomic absorption spectrometry are used; a good agreement is foudn among the different techniques. Different procedures of samples chemical dissolution are compared.
Abstract
A description is given of the preparation of copper hexacyanoferrate(II) supported on silica granules. The material in this form is suitable for use as adsorber in batch for concentrating trace cesium from cea water. A modified procedure for collecting cesium from large volumes of river water consists in the use of a column filled with the absorber that is oxidized to copper hexacyanoferrate(III) prior to use.
