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[en] First investigations of chemical properties of bohrium (Z = 107) and hassium (Z = 108) showed an expected behaviour as ordinary members of groups 7 and 8 of the periodic table. Two attempts to study element 112 yielded some indication for a behaviour like a very volatile noble metal. However, a very recent experiment to confirm this preliminary observation failed. Two examples are described how chemical studies may help to support element discovery claims from purely physics experiments. The two examples are the discovery claims of the elements 112 and 115, respectively, where the progenies hassium and dubnium were chemically identified. (orig.)
[en] Although somewhat in the shadow of the discoveries of new elements, experimental chemical investigations of the heaviest elements have made tremendous progress in the last decades. Indeed, it was possible to experimentally determine thermochemical properties of heavy transactinide elements such as copernicium or flerovium. But will it be possible to chemically study all currently known elements of the periodic table up to element 118? While it is experimentally feasible to work with single atoms, the short half-lives of even the longest currently known isotopes of elements 115 through 118 call for new experimental approaches.
[en] An international commission set up by IUPAP and IUPAC (International Union of Pure and Applied Physics/ Chemistry) in 1987 and chaired by Sir Denys Wilkinson has published its findings on the status of the transfermium elements (beyond atomic number 100) and the credit for the various discoveries
[en] In the presentation, we will overview results of atomic calculations till Z=122 that are important for placing these elements in the Periodic Table. They are also used for predictions of adsorption of atoms of these elements on neutral surfaces to guarantee their transportation from an accelerator to the chemistry set up. For the gas-phase chemistry experiments, predictions of volatility of group-4 through 8 compounds are presented and compared. General trends and a common character of the chemical behaviour are outlined. Predictions of volatility of elements in the atomic state, like of element 112, Cn, element 113, and element 114, Fl, as adsorption on neutral and metal surfaces are also described and compared. Interesting cases of volatility of even heavier elements, like 115, or 119 and 120 are considered. Influence of relativistic effects on properties and experimental behaviour of the heaviest elements is elucidated. Future perspectives for the chemical studies on the heaviest elements from the theoretical point of view are outlined
[en] Fast chemical separation methods having recently been developed for transactinide elements, it has been possible to study neutron-rich nuclides of longer half-life, and in particular the chemical behaviour of element 106, seaborgium. The report explains the online methods applied, as for instance extraction in a scintillator and measurements with pulse shape discrimination and parent-daughter correlation. (DG)
[de]Durch die Entwicklung schneller chemischer Trennmethoden fuer Transaktinidenelemente werden neutronenreiche Nuklide mit laengeren Halbwertzeiten und insbesondere das chemische Verhalten des Elements 106, Seaborgium, untersucht. Die hierzu vorgesehenen on-line Verfahren, wie z.B. die Extraktion in einen Szintillator und Messung mit Pulsformdiskriminierung und Mutter-Tochter-Korrelation, werden beschrieben. (DG)
[en] CdGa_2S_4 single crystals were grown by chemical transport reactions. Roentgen dosimetric properties of CdGa_2S_4 single crystals were studied. It was shown that roentgen sensitivity coefficient (K) of studied single crystal varies at effective hardness of X-rays Va = 25-50 keV and dose rate E 0.75-78.05 R/min. It is established that K for CdGa_2S_4 single crystals increases with an increase in the dose rate E, but with an increase in the accelerating voltage (Va) coefficient K decreases. From roentgen ampere characteristics of Cadges it follows that the dependence of the stationary X-ray current on X-ray dose has a power character. At high dose rate of hard X-rays, α tends to 1.0 for CdGa_2S_4 single crystal
[en] The author presents in detail the elements of the seventh subgroup (manganese group). He shows that the elements of this group, with the exception of manganese, are chemically usually relatively inert and show regular gradations of their properties. Thus, from manganese to rhenium density, melting and boiling points increase, but the reactivity decreases. Manganese is found as a constituent of very hard steels, technetium is used as a radiotherapeutic agent, manganese dioxide is needed in electric batteries, potassium permanganate as a disinfectant and rhenium as a component of fatigue-free alloys for turbine blades. Technetium was the first element that could only be synthesized for the first time. Rhenium is one of the rarest elements in the Earth's shell and only manganese is still relatively abundant at 850 ppm. Bohrium, the heaviest element in the group, is also only accessible through artificial processes (nuclear fusion).
[de]Der Autor stellt ausfuehrlich die Elemente der siebten Nebengruppe (Mangangruppe) vor. Er zeigt, dass die Elemente dieser Gruppe, mit Ausnahme des Mangans, chemisch meist relativ reaktionstraege sind und regelmaessige Abstufungen ihrer Eigenschaften zeigen. So nehmen vom Mangan zum Rhenium Dichte, Schmelz- und Siedepunkte zu, die Reaktivitaet jedoch ab. Mangan findet sich als Bestandteil sehr harter Staehle, Technetium wird als Radiotherapeutikum eingesetzt, Braunstein wird in Batterien benoetigt, Kaliumpermanganat als Desinfektionsmittel und Rhenium als Bestandteil ermuedungsfreier Legierungen fuer Turbinenschaufeln eingesetzt. Technetium war das erste Element, das nur auf kuenstlichem Wege erstmals dargestellt werden konnte, Rhenium ist eines der seltensten Elemente in der Erdhuelle und nur Mangan kommt mit einem Anteil von 850 ppm noch relativ verbreitet vor. Bohrium wiederum, das schwerste Element der Gruppe, ist ebenfalls nur durch kuenstliche Prozesse (Kernfusion) zugaenglich.
[en] Emergence of superheavy nuclei and hypernuclei, two fields of intense research in nuclear physics, has made a big impact on the nuclear chart; while the discovery of the superheavy oganesson has completed the seven full rows of the periodic table, discovery of several exotic hypernuclei have added a third dimension, called strangeness, to the existing nuclear chart. Highlights of some recent developments in these two fields are presented. (author)
[en] The discovery of the elements 113, 115, 117 and 118 was announced on december 30. 2015 by the UICPA (International Union of Pure and Applied Chemistry). This announcement was based on the conclusions of an expert group the Joint Working Party (JWP) and became soon polemical as some scientists began questioning the quality of the assessment and the fact that the UIPPA (International Union of Pure and Applied Physics) had not been informed before the announcement. In order to avoid some future misunderstandings, the UICPA and the UIPPA have agreed on a procedure to implement officially any new element. In the new procedure, published in may 2018, the chairmen of UICPA and UIPPA have the possibility of examining the conclusions of the JWP before any announcement, they can also lead their own peer assessment and draw their own conclusions. (A.C.)