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1913680931913. Physik. Zschr. 14/18. - Leipzig Verlag von S. Hirzel 15. September 1913 8° pp.857-912 4 Tafeln Rückenbroschur; St.a.Tit. First Edition! "In attempting to find uranium X2 Fajans and Göhring applied the generalization that after a beta transformation the daughter element is electrochemically more noble than the mother element. A solution of uranium X was placed in a lead dish with the expectation that "ekatantalum" is more thorium less noble than lead. In fact radioactive material was formed on the surface of the lead dish and its ß- activity decayed with the previously not known half life 1.1 min. Its chemical nature was further confirmed by its coprecipitation from solution with hydrous tantalumV oxide. Because uranium X2 occupied a previously vacant space in the periodic system it constituted a new element the nuclide received6 the distinctive name brevium Bv suggested by its short life." Fajans K. Physik. Z. 14136 1913. Fajans K. and Göhring O. Naturwissenschaft 1 399 1913. Fajans K. and Göhring O. Physik. Z. 14 877 1913. "In 1913 Kazimierz Kasimir Fajans 1887-1975 and Oswald Göhring 1889-c.1915 discovered the element number 91as its short-lived isotope 234mPa. They named it brevium Bv. The discovery was the result of the displacement law discovered by Alexander Smith Russell Frederick Soddy and Fajans. According to this law and the periodic system of Dimitri Mendeleev the daughter of uranium UX must contain an unknown radioelement chemical similar to tantalum. In 1918 during the search of the mother of actinium Otto Hahn and Lise Meitner found the long-lived Isotope of Brevium 231Pa which they designated as protactinium. Later often is written that Hahn and Meitner have non-only given the name but also discovered the element number 91" Siegfried Niese: Die Entdeckung des Elementes 91 durch Kasimir Fajans und Oswald Göhring im Jahr 1913 und die Namensgebung durch Otto Hahn und Lise Meitner 1918 unknown