Les Prix Nobel

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Imprimerie Royale., 1909
Volume for 1901 has a sketch of Alfred Nobel and his works, by P.T. Cleve.
 

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Página 4 - The results obtained so far point to the conclusion that the beginning of the succession of chemical changes taking place in radioactive bodies is due to the emission of the a-rays, ie the projection of a heavy charged mass from the atom. The portion left behind is unstable, undergoing further chemical changes which are again accompanied by the emission of a-rays, and in some cases also of £-rays.
Página 2 - These experiments show that the uranium radiation is complex, and that there are present at least two distinct types of radiation — one that is very readily absorbed, which will be termed for convenience the a radiation, and the other of a more penetrative character, which will be termed the /3 radiation.
Página 11 - ... can lose two electrons in this way, the double positive charge is explained. We have seen that there is every reason to believe that the a-particles, so freely expelled from the great majority of radioactive substances, are identical in mass and constitution and must consist of atoms of helium. We are consequently driven to the conclusion that the atoms of the primary radioactive elements like uranium and thorium must be built up in part at least of atoms of helium. These atoms are released at...
Página 11 - ... carry a double charge. It must not however be forgotten that the a-particle is released at a high speed as a result of an intense atomic explosion, and plunges through the molecules of matter in its path. Such conditions are exceptionably favourable to the release of loosely attached electrons from the atomic system. If the a-particle can lose two electrons in this way, the double positive charge is explained. We have seen that there is every reason to believe that the a-particles, so freely...
Página 6 - ... radioactive properties of the matter in question, although in the present instances radioactivity has furnished a convenient means of accurately studying the problem. The helium is given off from the mineral fergusonite, for example, in part when it is heated, and completely by dissolving the mineral. It is therefore to be expected that if any of the unknown ultimate products of the changes of a radioactive element are gaseous, they would be found occluded, possibly in considerable quantities,...
Página 4 - ... ie the projection of a heavy charged mass from the atom. The portion left behind is unstable, undergoing further chemical changes which are again accompanied by the emission of a rays, and in some cases also of /? rays. The power possessed by the radioactive bodies of apparently spontaneously projecting large masses with enormous velocities supports the view that the atoms of these substances are made up, in part at least, of rapidly rotating or oscillating systems of heavy charged bodies large...
Página 34 - Die Lebensanschauungen der grossen Denker : eine Entwickelungsgeschichte des Lebensproblems der Menschheit von Plato bis zur Gegenwart.
Página 9 - Apart from the importance of these results for radio-active data, the experiments are of themselves noteworthy, for it is the first time that it has been found possible to detect a single atom of matter.
Página 11 - Considering the evidence together, we conclude that the a-particle is a projected atom of helium, which has, or in some way during its flight acquires, two unit charges of positive electricity. It is somewhat unexpected that the atom of a monatomic gas like helium should carry a double charge. It must not however be forgotten that the a-particle is released at a high speed as a result of an intense atomic explosion, and plunges through the molecules of matter in its path. Such conditions are exceptionably...
Página 22 - ... progenitor the Nobel Prize designed for original work in the domain of chemistry — thus affording a new proof to be added to the numerous existing ones, of the intimate interplay one upon another of the various branches of natural science in modem times.

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