George De Hevesy 1 George De Hevesy

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George De Hevesy 1 George De Hevesy George de Hevesy 1 George de Hevesy György Hevesy Born 1 August 1885 Budapest, Hungary Died 5 July 1966 (aged 80) Freiburg, Germany Citizenship Germany Nationality Hungarian Fields Chemistry Institutions Ghent University University of Budapest Niels Bohr Institute ETH Zürich University of Freiburg University of Manchester Stefan Meyer Institute for Subatomic Physics Alma mater University of Freiburg Doctoral advisor Georg Franz Julius Meyer Doctoral students Max Pahl Known for • Hafnium • Radioactive tracer Notable awards Nobel Prize for Chemistry (1943) George Charles de Hevesy, Georg Karl von Hevesy, (1 August 1885 – 5 July 1966) was a Hungarian radiochemist and Nobel laureate, recognized in 1943 for his key role in the development of radioactive tracers to study chemical processes such as in the metabolism of animals. He also co-discovered the element hafnium. Biography Early years Hevesy György was born in Budapest, Hungary to a wealthy and ennobled Hungarian Jewish[1] family, the fifth of eight children to his parents Lajos (Louis) Bischitz and Baroness Eugenia (Jenny) Schossberger (ennobled as "De Tornya"). Grandparents from both sides of the family had provided the presidents of the Jewish community of Pest.[1] George grew up in Budapest and graduated high school in 1903 from Piarista Gimnázium. The family's name in the 1904 was Hevesy-Bischitz, and Hevesy later changed his own. George de Hevesy 2 De Hevesy began his studies in chemistry at the University of Budapest for one year, and at the Technical University of Berlin for several months, but changed to the University of Freiburg. There he came in contact with Ludwig Gattermann. In 1906 he started his Ph.D. thesis with Georg Franz Julius Meyer, acquiring his doctorate in physics in 1908. In 1908 Hevesy got a position at the ETH. Research In 1923 de Hevesy co-discovered hafnium ( Hf) (Latin Hafnia for "Copenhagen", the home town of Niels Bohr), 72 with Dirk Coster. Mendeleev's periodic table in 1869 put the chemical elements into a logical system, however there was missing a chemical element with 72 protons. On the basis of Bohr's atomic model Hevesy came to the conclusion that there must be a chemical element that goes there. The mineralogical museum of Norway and Greenland in Copenhagen furnished the material for the research. Characteristic X-ray spectra recordings made of the sample indicated that a new element was present. This earned him the 1943 Nobel Prize in Chemistry. Hevesy was offered and accepted a job from the University of Freiburg. Supported financially by the Rockefeller Foundation, he had a very productive year. He developed the X-ray fluorescence analytical method, and discovered the Samarium alpha-ray. It was here he began the use of radioactive isotopes in studying the metabolic processes of plants and animals, by tracing chemicals in the body by replacing part of stable isotopes with small quantities of the radioactive isotopes. In 1923, Hevesy published the first study on the use of the naturally radioactive 212Pb as radioactive tracer to follow the absorption and translocation in the roots, stems and leaves of Vicia faba, also known as the broad bean.[2][3] World War II and beyond When Germany invaded Denmark in World War II, de Hevesy dissolved the gold Nobel Prizes of Max von Laue and James Franck with aqua regia; it was illegal at the time to send gold out of the country, and were it discovered that Laue and Franck had done so to prevent them from being stolen, they could have faced prosecution in Germany. He placed the resulting solution on a shelf in his laboratory at the Niels Bohr Institute. After the war, he returned to find the solution undisturbed and precipitated the gold out of the acid. The Nobel Society then recast the Nobel Prizes using the original gold.[4][5] In 1943, Copenhagen was no longer seen as safe for a Jewish scientist, and de Hevesy fled to Sweden, where he worked at the Stockholm University College until 1961. Interestingly enough, in Stockholm, de Hevesy was received at the department of German by the Swedish professor and Nobel Prize winner Hans von Euler-Chelpin, who remained strongly pro-German throughout the war. Despite this, de Hevesy and von Euler-Chelpin collaborated on many scientific papers during and after the war. During his time in Stockholm, de Hevesy received the Nobel Prize in chemistry. He later was inducted as a member of the Royal Society and received the Copley Medal, of which he was particularly proud. De Hevesy stated: "The public thinks the Nobel Prize in chemistry for the highest honor that a scientist can receive, but it is not so. Forty or fifty received Nobel chemistry prizes, but only ten foreign members of the Royal Society and two (Bohr and Hevesy) received a medal-Copley." George de Hevesy was elected a foreign member of the Royal Swedish Academy of Sciences in 1942, and his status was later changed to Swedish member. He received the Atoms for Peace Award in 1958 for his peaceful use of radioactive isotopes. George de Hevesy 3 De Hevesy married Pia Riis in 1924. They had one son and three daughters together. De Hevesy died in 1966 at the age of eighty and was buried in the Kerepesi Cemetery in Budapest, Hungary.[6] He had published a total of 397 scientific publications, one of which was the Becquerel-Curie Memorial Lecture, in which he had reminisced about the careers of pioneers of radiochemistry.[7] At his family's request, his ashes were interred at his birthplace in Budapest on April 19, 2001. 10 May 2005 [8] the Hevesy Laboratory [9] was founded at Risø National Laboratory for Sustainable Energy, now DTU (Technical University of Denmark) Risø Campus [10]. It was named after George de Hevesy as the father of the isotope tracer principle by the initiative of the lab's first head Prof. Mikael Jensen [11]. References George de Hevesy's grave in Budapest. Cemetery [1] Levi, Hilde (1985), George de Hevesy : life and work : a biography, Bristol: A. Kerepesi: 27 Hungarian Academy of Sciences. Hilger, p. 14, ISBN 9780852745557 [2] Myers, W.G. (June 1979), "Georg Charles de Hevesy: the father of nuclear medicine" (http:/ / jnm. snmjournals. org/ content/ 20/ 6/ 590. full. pdf), Journal of nuclear medicine 20 (6): 590–4, PMID 395289, , retrieved 2 May 2012. [3] Hevesy, G. (1923). "The Absorption and Translocation of Lead by Plants: A Contribution to the Application of the Method of Radioactive Indicators in the Investigation of the Change of Substance in Plants." (http:/ / www. ncbi. nlm. nih. gov/ pmc/ articles/ PMC1263906/ pdf/ biochemj01165-0003. pdf). The Biochemical journal 17 (4-5): 439–45. PMC 1263906. PMID 16743235. Retrieved 6 May 2012. [4] Hevesy, George (1962), Adventures in radioisotope research (http:/ / www. archive. org/ stream/ adventuresinradi01heve#page/ 27/ mode/ 1up/ search/ medals), 1, New York: Pergamon press, p. 27, [5] Birgitta Lemmel (2006). "The Nobel Prize Medals and the Medal for the Prize in Economics" (http:/ / nobelprize. org/ nobel_prizes/ about/ medals/ ). The Nobel Foundation. [6] George Charles De Hevesy (http:/ / www. findagrave. com/ cgi-bin/ fg. cgi?page=gr& GRid=13864548). findagrave.com [7] De Hevesy, George C. (1961), "Marie Curie and her contemporaries" (http:/ / jnm. snmjournals. org/ content/ 25/ 1/ 116. full. pdf), Journal of nuclear medicine 2: 169–82, PMID 13714019, [8] http:/ / www. risoe. dtu. dk/ rispubl/ BIG/ hevesey_2005. pdf [9] http:/ / www. nutech. dtu. dk/ NUK/ ISO. aspx?sc_lang=en [10] http:/ / www. risoe. dtu. dk/ ?sc_lang=en [11] http:/ / orbit. dtu. dk/ en/ persons/ mikael-jensen(7a6b32c7-c6b6-4fbf-af7f-f0e64f27de43). html Further reading • Levi, H. (1976), "George von Hevesy memorial lecture. George Hevesy and his concept of radioactive indicators—in retrospect", European Journal of Nuclear Medicine 1 (1): 3–10, PMID 797570 • Ostrowski, W. (1968), "George Hevesy inventor of isotope methods in biochemical studies", Postepy Biochem. 14 (1): 149–53, PMID 4870858 • Dal Santo, G. (1966), "Professor George C. De Hevesy. In reverent memory", Acta Isotopica 6 (1): 5–8, 1966 Sep 30, PMID 4865432 • "George De Hevesy", Triangle; the Sandoz Journal of Medical Science 91: 239–40, 1964, 1964 Jul, PMID 14184278 • Cockcroft, John D. (1967), "George de Hevesy. 1885–1966", Biographical Memoirs of Fellows of the Royal Society 13 (42): 125–166, doi:10.1098/rsbm.1967.0007, JSTOR 769376. • Weintraub, B. (April 2005), "George de Hevesy: Hafnium and Radioactive Traces; Chemistry" (http:/ / www. chemistry. org. il/ booklet/ 18/ pdf/ weintraub. pdf), Bull. Isr. Chem. Soc. (18): 41–43. George de Hevesy 4 External links • George de Hevesy – Biography (http:/ / nobelprize. org/ chemistry/ laureates/ 1943/ hevesy-bio. html) • Annotated bibliography for George de Hevesy from the Alsos Digital Library for Nuclear Issues (http:/ / alsos. wlu. edu/ qsearch. aspx?browse=people/ Hevesy,+ George+ de) Article Sources and Contributors 5 Article Sources and Contributors George de Hevesy Source: http://en.wikipedia.org/w/index.php?oldid=535196645 Contributors: 1966batfan, Adam78, Afernand74, Aleichem, AmosClecure, Angela, Aquillion, Astrochemist, Avaya1, BD2412, Baxter9, Bender235, Brian the Editor, Burubuz, Cassandro, Chicheley, Chris the speller, D6, DESiegel, David Berardan, Davshul, Dirac1933, Dori, Double sharp, E.Kupsova, Eastfrisian, Emerson7, EternalFlare, Eustress, Fnielsen, Galloping Ghost U of I, GcSwRhIc, Gcm, Giftlite, Hede2000, HennessyC, Jacek Kendysz, Japanese Searobin, Joey80, John, John of Reading, Joy, Karl gregory jones, Kbdank71, Lateg, Materialscientist,
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