In the fifty years since the discovery of nuclear fission, the field of the study of the chemical and nuclear properties of the man-made elements has been transformed from a frontier science, with a small number of important experiments being performed under very difficult circumstances, to a mature science with encompasses many subfields, and whose techniques are widely used in science and industry. Today, experiments are being performed, on a routine basis, with technology far beyond that available fifty years ago. Here, we have looked fifty years into the future and tried to foresee the state of the field of the study of the man-made elements in the year 2039, on the 100th anniversary of the discovery of nuclear fission.
Authors:D. Hoffman, R. Henderson, K. Gregorich, D. Bennett, R. Chasteler, C. Gannett, H. Hall, D. Lee, M. Nurmia, S. Cai, R. Agarwal, A. Charlop, Y. Chu, G. Seaborg, and R. Silva
The isotope260Lr, produced in reactions of18O with249Bk, was used to perform chemical experiments on lawrencium to learn more about its chemical properties. These experiments involved extractions with thenoyl trifluoroacetate, elutions from cation exchange resin columns with ammonium alpha-hydroxyisobutyrate, and reverse-phase chromatography using hydrogen di(2-ethylhexyl) orthophosphoric acid to investigate the chemical properties of Lr. The results from the elutions gave information about the ionic radius of Lr(III) which was found to elute very close to Er. An attempt to reduce Lr(III) with hydroxylamine hydrochloride was unsuccessful.
Authors:A. Türler, H. Gäggeler, K. Gregorich, H. Barth, W. Brüchle, K. Czerwinski, M. Gober, N. Hannink, R. Henderson, D. Hoffman, D. Jost, C. Kacher, B. Kadkhodayan, J. Kovacs, J. Kratz, S. Kreek, D. Lee, J. Leyba, M. Nurmia, M. Schädel, U. Scherer, Schimpf, D. Vermeulen, A. Weber, H. Zimmermann, and I. Zvara
On-line isothermal gas phase chromatography was used to study halides of261104 (T1/2=65 s) and262,263105 (T1/2=34 s and 27 s) produced an atom-at-a time via the reactions248Cm(18O, 5n) and249Bk(18O, 5n, 4n), respectively. Using HBr and HCl gas as halogenating agents, we were able to produce volatile bromides and chlorides of the above mentioned elements and study their behavior compared to their lighter homologs in Groups 4 or 5 of the periodic table. Element 104 formed more volatile bromide than its homolog Hf. In contrast, element 105 bromides were found to be less volatile than the bromides of the group 5 elements Nb and Ta. Both 104 and Hf chlorides were observed to be more volatile than their respective bromides.
Authors:B. Wierczinski, K. Gregorich, B. Kadkhodayan, D. Lee, L. Beauvais, M. Hendricks, C. Kacher, M. Lane, D. Keeney-Shaughnessy, N. Stoyer, D. Strellis, E. Sylwester, P. Wilk, D. Hoffman, R. Malmbeck, G. Skarnemark, J. Alstad, J. Omtvedt, K. Eberhardt, M. Mendel, A. Nähler, and N. Trautmann
Subsecond 224 Pa (T1/2 = 0.85 s) was produced via the 209 Bi(18 O,3n)224 Pa reaction at the 88 inch cyclotron at the Lawrence Berkeley National Laboratory. After production it was transported via a gas-jet system to the centrifuge system SISAK 3. Following on-line extraction with trioctylamine/scintillation solutions from 1M lactic acid, 224 Pa was detected applying on-line -liquid scintillation counting. Unambiguous identification was achieved using time-correlated --decay chain analysis. This constitutes the first chemical on-line separation and detection of a subsecond -decaying nuclide, 0.85-s 224 Pa with the fast extraction system SISAK 3.