101. British Mass Spectrometry Society - Awards takes the name of one of Britain s founders of mass spectrometry francisWilliam aston. Find out more about francis aston . Selection committee http://www.bmss.org.uk/medals.htm

awards - medals The Aston Medal was established by the British Mass Spectrometry Society in 1987. As the Society's prestigious scientific award, it is to be given to individuals deserving special recognition by reason of their outstanding contributions to knowledge in the biological, chemical, engineering, mathematical, medical, or physical sciences relating directly to mass spectrometry. Award of Life membership of the BMSS Life membership of the British Mass Spectrometry Society is a prestigious award given to members of the Society who have made a significant contribution to the practice of mass spectrometry in the U.K. or, perhaps more importantly in this case, to the Society itself. retirement age on an automatic basis and indeed most members of the Society will probably not satisfy the criteria. awarded in any year. attendance at meetings.

102. ChemTeam: Aston - Isotopes And Atomic Weights By Dr FW aston Nature 105, p. 617. from the two following quotations fromSir william Ramsay s address to the British Association at Toronto in 1897 http://dbhs.wvusd.k12.ca.us/webdocs/Chem-History/Aston-MassSpec.html

ISOTOPES AND ATOMIC WEIGHTS By Dr F. W. Aston Nature : 105, p. 617. In the atomic theory put forward by John Dalton in 1801 the second postulate was: "Atoms of the same element are similar to one another and equal in weight." For more than a century this was regarded by chemists and physicists alike as an article of scientific faith. The only item among the immense quantities of knowledge acquired during that productive period which offered the faintest suggestion against its validity was the inexplicable mixture of order and disorder among the elementary atomic weights. The general state of opinion at the end of last century may be gathered from the two following quotations from Sir William Ramsay's address to the British Association at Toronto in 1897: This idea was placed on an altogether different footing some ten years later by the work of Sir Ernest Rutherford and his colleagues on radio-active transformations. The results of these led inevitably to the conclusion that there must exist elements which have chemical properties identical for all practical purposes, but the atoms of which have different weights. This conclusion has been recently confirmed in a most convincing manner by the production in quantity of specimens of lead from radio-active and other sources, which, though perfectly pure and chemically indistinguishable, give atomic weights differing by amounts quite outside the possible experimental error. Elements differing in mass but chemically identical and therefore occupying the same position in the periodic table have been called "isotopes" by Prof. Soddy.

103. Aston Nationalité britannique; Physicien; aston a découvert l existence des isotopes*. http://hebergement.ac-poitiers.fr/l-jv-larochelle/site_eleves_2/Pages/francais/s

Aston, Francis William Né en 1877 à Harbone et décédé à Cambridge en 1945 Nationalité britannique Physicien Aston a découvert l'existence des isotopes*. Il a reçu le prix Nobel en 1922. * : éléments chimiques dont seul le nombre de neutrons dans le noyau diffère (deux isotopes ont les mêmes propriétés chimiques) sur internet... Les grands chimistes : http://www.chm.ulaval.ca/gchimistes/gchimistes.html Sur le site des Prix Nobel : http://www.nobel.se/ Un autre site consacré aux prix Nobel : http://www.almaz.com/nobel/ cliquez sur un des boutons ci-dessus pour visiter l'un de nos menus de recherche

104. Science Museum London - Treasures Whilst working at the Cavendish Laboratory in Cambridge under J J Thomson, FrancisWilliam aston (18771945) undertook a series of experiments that led to http://www.sciencemuseum.org.uk/on-line/treasure/objects/1927-1085.asp

Aston's Mass Spectograph Whilst working at the Cavendish Laboratory in Cambridge under J J Thomson, Francis William Aston (1877-1945) undertook a series of experiments that led to the discoveries by which he is now best remembered. Aston was assigned to improving Thomson's apparatus in which a beam of positively-charged particles (positive rays) was deflected by a combination of electric and magnetic fields into sharp visible curves, each representing an individual particle's charge-to-mass ratio. The key advance Aston made to Thomson's apparatus was his arrangement of the electric and magnetic deflecting fields so as to bring rays of uniform charge-to-mass ratio to sharp focus on a photographic plate. Aston devised several methods for calibrating his instrument and, in the case of neon, obtained mass lines on his photographic plate at 20 and 22 with the intensities of the lines showing that the two particles occurred in the ratio of 10:1, consistent with an average mass of 20.20, the known atomic weight of neon. He had earlier shown that both masses were substances with the same properties as neon and thus neon was the first non-radioactive element proven to be isotopic (atoms with the same chemical properties, but different atomic mass).

105. Prix Nobel De 1920 à 1924 http://membres.lycos.fr/xjarnot/Chimistes/Nobel_1920.html

P rix Nobel de 1920 à 1924 Hermann Walther Nernst Frederick Soddy Francis William Aston Fritz Pregl Le prix Nobel de chimie n'a pas été attribué 1920. Hermann Walther Nernst En reconnaissance de ses travaux en thermochimie. Hermann Walther Nemst est né le 25 juin 1864 à Briessen, en Prusse Orientale (aujourd'hui Wabrzezno en Pologne); c'est lui qui a consolidé les bases de la chimie physique du XXe siècle. Il commence à travailler dans cette discipline auprès de Kohlrausch, à Würzbourg, où il fait la connaissance d'Arrhenius, qui l'amène ensuite à Graz, chez von Ettinghausen. Là, il entreprend des travaux sur les fnrces électromotrices dues au magnétisme des plaques métalliques que traverse un flux de chaleur. Sur la recommandation d'Arrhenius, il devient l'assistant d'Ostwald, qui était alors professeur de chimie physique à Leigzig, et commence de nouvelles recherches en électrochimie. En 1888, il publie la théorie dite aujourd'hui "théorie de Nernst" sur la force électromotrice, suivie en 1889 d'un mémoire intitulé "L'activité élcctromotrice des ions". Cette théorie très féconde constituc la base de l'électrochimie théorique; elle est à l'origine des progrès techniqucs en électrochimie et du développement de l'électrobiologie. Selon Nemst, un métal en solution se comportc comme un donneur d'élcctrons vis-à-vis de la solution; il existe une tension de dissolution électrolytique propre à chaque métal, forte pour les métaux comme le zinc, faible au contraire pour les métaux nobles comme le platine. Ce phénomène se traduit par une augmentation de la pression osmotique des ions en solution, qui aura tendance à s'opposer à la tension de dissolution. Il est alors possible de calculer le travail mis en jeu lorsqu'une mole d'ions passe de la pression de dissolution électrolytique à la pression osmotique de la solution. On peut aussi transposer ce raisonnement aux surfaces de séparation en solutions de concentrations différentes. On sait aujourd'hui que les rclations dtablies par Nemst ne sont valables que pour les solutions dilu

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