Automated Rapid Chemistry Apparatus

The Lawrence Berkeley Laboratory and other groups were unable to confirm the spontaneous-fission reaction of Ku-260, so the Dubna groups discovery was disputed. The Berkeley equipment was unable to accelerate neon ions to the speeds required to produce Ku-260, and thus they tried a different reaction in a new automated rapid chemistry apparatus that identified and confirmed new isotopes of heavy metals. The procedure involved bombarding the element californium-239 with a mixture of the isotopes carbon-12 and carbon-13 ions, as follows ... 

Extensive studies of chemical properties of transactinide elements, Rf, Db, and Sg have been performed with the Automated Rapid Chemistry Apparatus (ARCA), see summaries in Ref. [15, 44, 45]. To improve the speed and reduce cross contamination, the ARCA n was built, featuring two magazines of 20 miniaturized ion exchange columns [46]. With the large number of columns, cross contamination between samples can be prevented by using each column only once. By miniaturizing the columns, the elution... 

Figure 16.6. (a) B. Kadkhodayan with HEVI (1992) (b) J. Kovacs and H. W. Gaggeler with OLGA (1988) (c) D. C. Hoffman and D. M. Lee with MG rotating wheel system (d) J. V. Kratz and M. Schadel with Automated Rapid Chemistry Apparatus (1988) (e) Schematic diagram of a typical SISAK liquid-liquid extraction configuration with Berkeley Gas-filled Separator as a preseparator. 

There is another problem with man-made chemical elements, namely that their isotopes are short lived too. This, together with the need for their identification, calls for fast separation methods. The Automated Rapid Chemistry Apparatus (ARCA) II S) tem and the Short-lived Isotopes Studied by the AKUFVE-technique (SISAK) equipment (both described in Sect. 59.2.2 of Chap. 59, Vol. 6, on Solvent Extraction and Ion Exchange in Radiochemistry ) are able to handle radionuclides with half-lives of -10 s and 1 s, respectively. 

E reaction. The first method involved a series of solvent extractions performed continuously with the centrifuge system SISAK (Short-lived Isotopes Studied by the AKUFVE Technique) (Skarnemark et al. 1980) and the second one involved the ion-exchange separation apparatus ARCA (Automated Rapid Chemistry Apparatus) (Schadel et al. 1989). In the case of... 

The Automated Rapid Chemistry Apparatus, ARCA II (Schadel et al. 1989), that has been so successfiil in studying chemical properties of element 105 (Kratz 1994 Paulus et al. 1999a, b)... 

Schadel, M., Briichle, W., Haefner, B. Fast ladiochemical separations with an automated rapid chemistry apparatus. Nucl. Instmm. Methods Phys. Res. A264, 308-318 (1988)... 

In 1995, the first study of the chemical properties of Sg in aqueous solution was performed. A short account of these experiments and their results was published by Schadel et al. [105]. Here, we give a more detailed report on the experiments including the results of a follow-up experiment performed in 1996. These involved the Automated Rapid Chemistry Apparatus, ARCAII [1], that has been successful in studying chemical properties of Db [75, 79] and of Rf [36, 40] in aqueous solutions. 

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