Separation of Short-Lived Isotopes

MacFarlane and Griffioen [130] introduced another transport technique which was later used in many other investigations, e.g., [3, 6, 18, 38, 53, 60, 79, 95, 100, 108]. The reaction products, which either recoil out or evaporate/desorb from the (hot) target, are slowed down in a gas, which is then used to transport the radionuclides to the counting equipment. The separation of the activity from the gas stream is accomplished by directing the gas jet evolving from a nozzle against a catcher. The distance between nozzle and catcher 

The transport of the produced activity with a carrier gas can be used for a chemical separation by adding a reactive gas to the carrier gas. This method of inorganic gas chromatography with a thermal gradient in the column was first applied by Zvara et al. [83] to separate superheavy nuclides. Matschoss and Bachmann [35] used this procedure, for instance, to separate Ru from fission products. It is also possible (see Fig. 1-28) to combine a He-jet system with a gas chromatographic separation [29, 33, 38]. 

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Reproduced from Nuclear instruments and methods in physics research A, 551(2-3), Dullmann ChE, Folden CM, Gregory KE, et al., Heavy ion induced production and physical pre-separation of short lived isotopes for chemistry experiments, 528-539, 2005 with permission from Elsevier. 

In the first part (Chapter 1.2.1, p. 6) a general survey about masses and decay data is given. Their systematic behavior, i.e., their dependence on the proton number Z and nucleon number (mass number) A, is discussed. In Chapter 1.2.2 (p. 22) a quick overview on the decay data of the nuclides of the Pt group is given more detailed descriptions of nuclear and decay properties are compiled in Chapter 1.2.3, p. 29. The methods used for production and separation of short-lived isotopes from irradiated materials are summarized in Chapter 1.3, p. 126. 

Separation of short-lived carrier-free lead Isotopes from bismuth parents. 

A procedure for the rapid separation of berkelium from other actinides, lanthanides, and fission products was developed in order to measure the decay properties of short-lived isotopes [54]. Bk and Ce were separated from other elements using solvent extraction with HDEHP followed by cation-exchange high-pressure liquid chromatography (HPLC) using a-hydroxyisobutyrate as the eluant. The elution curve, showing a clean separation of Bk from Ce, is shown in... 

Fedoseyev, V. N., Fedorov, D. V., Horn, R., Huber, G., Koster, U., Lassen, J., Mishin, V. L, Seliverstov, M. D., Weisman, L., Wendt, K., and the ISOLDE Collaboration (2003). Atomic spectroscopy studies of short-lived isotopes and nuclear isomer separation with ISOLDE RILIS. Nuclear Instruments and Methods in Physical Research B, 204, 353—358. 

The recoil effect is useful for separating radionuclides. A fully mechanized apparatus has been desoibed for the continuous separation of short-lived radionuclides. The use of ch cal reactions of recoil atoms has been utilized for on-line separations of the required isotope in studies of nuclear reactions, using electromagnetic isotope separators. The systems studied were ... 

A He jet system [6], mass separators [19, 21, 22, 50], and a velocity filter [7] were also used for the separation of short-lived Pt isotopes. 

A number of the procedures developed for the rapid separation (lower limit 1-2 sec) of radioiodine from fission products for the study of short-lived Isotopes are derivative of the standard separation procedure described In section III and only one of those procedures (215) Is given here. Iodide In the fission product solution was oxidized to lodate by means of permanganate In acidic solution. This step was followed by reduction of lodate to molecular Iodine with hydroxylamine hydrochloride and extraction of the free element Into carbon tetrachloride. Iodine was back-extracted as Iodide Into an ammonlacal solution of sodium pyrosulfite and Iodide was precipitated as the silver salt. The time required for the procedure was about 150 sec and the separation yield was approximately 95%. 

Nuclear properties (spins, moments, charge radii) revealed by the analysis of hyperfine structure and isotope shift of atomic levels have been obtained in decades of experiments. Since 1975 with the introduction of tunable dye laser, the rebirth of the methods, some already known since 1930, had led to many on line experiments on short lived isotopes not investigated before. I report here a sample of the experiments done by the Orsay, Mainz groups at CERN. Although experiments have been carried out by the Orsay group using the proton beam of the CERN Proton Synchrotron, most of the experiments have been done at Isolde, the on - line mass separator at CERN, whose radioactive beams are essential to the success of these experiments [RAV 84]. 

The SISAK (Short-lived Isotopes Studied by the AKUFVE-technique, where AKUFVE is s Swedish acronym for an arrangement of continuous investigations of distribution ratios in liquid extraction) system performs continuous liquid-liquid extractions using small-volume separator centrifuges [66]. Activities are delivered to the apparatus with an aerosol... 

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