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Otto Hahn
Otto Hahn (; 8 March 1879 – 28 July 1968) was a German chemist who was a pioneer in the fields of radioactivity and radiochemistry. He is referred to as the father of nuclear chemistry and father of nuclear fission. Hahn and Lise Meitner discovered radioactive isotopes of radium, thorium, protactinium and uranium. He also discovered the phenomena of atomic recoil and nuclear isomerism, and pioneered rubidium–strontium dating. In 1938, Hahn, Lise Meitner and Fritz Strassmann discovered nuclear fission, for which Hahn received the 1944 Nobel Prize for Chemistry. Nuclear fission was the basis for nuclear reactors and nuclear weapons. A graduate of the University of Marburg, Hahn studied under Sir William Ramsay at University College London and at McGill University in Montreal under Ernest Rutherford, where he discovered several new radioactive isotopes. He returned to Germany in 1906; Emil Fischer placed a former woodworking shop in the basement of the Chemical Institute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frankfurt
Frankfurt, officially Frankfurt am Main (; Hessian: , "Frank ford on the Main"), is the most populous city in the German state of Hesse. Its 791,000 inhabitants as of 2022 make it the fifth-most populous city in Germany. Located on its namesake Main River, it forms a continuous conurbation with the neighboring city of Offenbach am Main and its urban area has a population of over 2.3 million. The city is the heart of the larger Rhine-Main metropolitan region, which has a population of more than 5.6 million and is Germany's second-largest metropolitan region after the Rhine-Ruhr region. Frankfurt's central business district, the Bankenviertel, lies about northwest of the geographic center of the EU at Gadheim, Lower Franconia. Like France and Franconia, the city is named after the Franks. Frankfurt is the largest city in the Rhine Franconian dialect area. Frankfurt was a city state, the Free City of Frankfurt, for nearly five centuries, and was one of the most import ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Ramsay
Sir William Ramsay (; 2 October 1852 – 23 July 1916) was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" along with his collaborator, John William Strutt, 3rd Baron Rayleigh, who received the Nobel Prize in Physics that same year for their discovery of argon. After the two men identified argon, Ramsay investigated other atmospheric gases. His work in isolating argon, helium, neon, krypton, and xenon led to the development of a new section of the periodic table. Early years Ramsay was born at 2 Clifton StreetGlasgow Post Office Directory 1852 in Glasgow on 2 October 1852, the son of civil engineer and surveyor, William C. Ramsay, and his wife, Catherine Robertson. The family lived at 2 Clifton Street in the city centre, a three-storey and basement Georgian townhouse. The family moved to 1 Oakvale Place in the Hillhead district in his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioactinium
Actinium is a chemical element with the symbol Ac and atomic number 89. It was first isolated by Friedrich Oskar Giesel in 1902, who gave it the name ''emanium''; the element got its name by being wrongly identified with a substance André-Louis Debierne found in 1899 and called actinium. Actinium gave the name to the actinide series, a group of 15 similar elements between actinium and lawrencium in the periodic table. Together with polonium, radium, and radon, actinium was one of the first non-primordial radioactive elements to be isolated. A soft, silvery-white radioactive metal, actinium reacts rapidly with oxygen and moisture in air forming a white coating of actinium oxide that prevents further oxidation. As with most lanthanides and many actinides, actinium assumes oxidation state +3 in nearly all its chemical compounds. Actinium is found only in traces in uranium and thorium ores as the isotope 227Ac, which decays with a half-life of 21.772 years, predominantly e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiothorium
Thorium (90Th) has seven naturally occurring isotopes but none are stable. One isotope, 232Th, is ''relatively'' stable, with a half-life of 1.405×1010 years, considerably longer than the age of the Earth, and even slightly longer than the generally accepted age of the universe. This isotope makes up nearly all natural thorium, so thorium was considered to be mononuclidic. However, in 2013, IUPAC reclassified thorium as binuclidic, due to large amounts of 230Th in deep seawater. Thorium has a characteristic terrestrial isotopic composition and thus a standard atomic weight can be given. Thirty-one radioisotopes have been characterized, with the most stable being 232Th, 230Th with a half-life of 75,380 years, 229Th with a half-life of 7,917 years, and 228Th with a half-life of 1.92 years. All of the remaining radioactive isotopes have half-lives that are less than thirty days and the majority of these have half-lives that are less than ten minutes. One isotope, 229Th, has a nucl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikolaus Riehl
Nikolaus Riehl (24 May 1901 – 2 August 1990) was a German nuclear physicist. He was head of the scientific headquarters of Auergesellschaft. When the Russians entered Berlin near the end of World War II, he was invited to the Soviet Union, where he stayed for 10 years. For his work on the Soviet atomic bomb project, he was awarded a Stalin Prize, Lenin Prize, and Order of the Red Banner of Labor. When he was repatriated to Germany in 1955, he chose to go to West Germany, where he joined Heinz Maier-Leibnitz on his nuclear reactor staff at Technische Hochschule München (THM); Riehl made contributions to the nuclear facility Forschungsreaktor München (FRM). In 1961 he became an ordinarius professor of technical physics at THM and concentrated his research activities on solid state physics, especially the physics of ice and the optical spectroscopy of solids. Education Riehl was born in Saint Petersburg, Russia in 1901. His mother Elena Riehl (née Kagan) was Russian-Jew ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siegfried Flügge
Siegfried Flügge (16 March 1912, in Dresden – 15 December 1997, in Hinterzarten) was a German theoretical physicist who made contributions to nuclear physics and the theoretical basis for nuclear weapons. He worked on the German nuclear energy project. From 1941 onward he was a lecturer at several German universities, and from 1956 to 1984, editor of the 54-volume, prestigious ''Handbuch der Physik''. Education From 1929 to 1933, Flügge studied physics at the ''Technische Hochschule Dresden'' (after 1961, the Dresden University of Technology) and the Georg-August University of Göttingen. He received his doctorate at the latter, under Max Born, in 1933. Career From 1933 to 1935, he was a teaching assistant at the Johann Wolfgang Goethe University Frankfurt am Main. From 1936 to 1937, he was a teaching assistant to Werner Heisenberg at the University of Leipzig. From 1937 to 1942, as successor to Max Delbrück, Flügge was an assistant to Otto Hahn at the ''Kaiser-Wilhe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans-Joachim Born
Hans-Joachim Born (8 May 1909 – 15 April 1987) was a German radiochemist trained and educated at the ''Kaiser-Wilhelm-Institut für Chemie''. Up to the end of World War II, he worked in Nikolaj Timofeev-Resovskij, Nikolaj Vladimirovich Timofeev-Resovskij's ''Abteilung für Experimentelle Genetik'', at the ''Kaiser-Wilhelm-Institut für Hirnforschung''. He was taken prisoner by the Russians at the close of World War II. After rescue from the Krasnoyarsk PoW camp, he initially worked in Nikolaus Riehl's group at Plant No. 12 in Elektrostal’, Russia, but at the end of 1947 was sent to work in Sungul' at a sharashka known under the cover name Ob’ekt 0211. At the Sungul' facility, he again worked in a biological research department under the direction of Timofeev-Resovskij. Upon arrival in East Germany in the mid-1950s, Born became the director of the ''Institut für Angewandte Isotopenforschung'' in Buch, Berlin. He also completed his ''Habilitation'' at the ''Technische Hochs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salomon Rosenblum
Salomon Aminyu Zalman Rosenblum (2 June 1896 – 22 November 1959) was a Poland-born nuclear physicist. He became a French citizen. He worked in the laboratory of Marie Curie in the commune of Arcueil, and led two CNRS laboratories at the ''Centre national de la recherche scientifique'' (CNRS). Early life Rosenblum was born in Ciechanowiec, in Russian-controlled Poland to Ita Miriam Rosenblum (née Horovitz) and Jehoshua Mordechai Rosenblum, a reasonably wealthy Jewish family. His studies were interrupted by World War I. He emigrated to Denmark and Sweden, studying philosophy at the University of Copenhagen and Hebrew, Armenian and Arabic at the University of Lund. A chance encounter and discussion with Niels Bohr's assistant in a café in Copenhagen led him to abandon his thesis on ancient languages and to commence studies in nuclear physics. After studying in Copenhagen and Berlin, he joined Curie's ''Institut du Radium'' in Paris in 1923, following Bohr's recommendation. His ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritz Strassmann
Friedrich Wilhelm Strassmann (; 22 February 1902 – 22 April 1980) was a German chemist who, with Otto Hahn in December 1938, identified the element barium as a product of the bombardment of uranium with neutrons. Their observation was the key piece of evidence necessary to identify the previously unknown phenomenon of nuclear fission, as was subsequently recognized and published by Lise Meitner and Otto Frisch. Personal life and education Strassman was born in Boppard, Germany, to Richard Strassman and Julie Strassmann (née Bernsmann). He was the youngest of nine children. Growing up in Düsseldorf, he developed an interest in chemistry at a young age and conducted chemistry experiments in his parents' home. His family was of modest means, and his father died at a young age, worsening the family's financial situation. Financial considerations limited Strassmann's initial choices of where to pursue his higher education and what subjects they should be. Strassmann began his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aristid Von Grosse
Aristid von Grosse (January 1905 – July 21, 1985) was a German nuclear chemist. During his work with Otto Hahn, he got access to waste material from radium production, and with this starting material he was able in 1927 to isolate protactinium(V) oxide and was later able to produce metallic protactinium by decomposition of protactinium(V) iodide. From 1948 to 1969, he was president of the Research Institute of Temple University and was later affiliated with the laboratories of the Franklin Institute in Philadelphia until his retirement in 1979. In 1971, he received a United States Atomic Energy Commission award in recognition of his "outstanding contributions to the development of nuclear energy." Aristid was born in Riga in January 1905 and moved to the United States in 1930. He retired in 1979 and died of pneumonia in Laguna Hills, California Laguna Hills (; ''Laguna'', Spanish for "Lagoon") is a city in south Orange County, California, United States. Its name refers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heidenhain
Dr. Johannes Heidenhain GmbH is a privately owned enterprise located in Traunreut, Germany that manufactures numerical controls for machine tools, as well as mechatronic measuring devices for length and angle. Their linear and angle encoders are built for use in automated machines and systems, particularly in machine tools. History The company began as a metal etching factory founded in Berlin by Wilhelm Heidenhain in 1889 that manufactured templates, company plaques, product labels, and scales. In 1928 Heidenhain invented the Metallur process. This lead-sulfide copying process made it possible for the first time to make exact copies of an original grating on a metal surface for industrial use. By 1943, Heidenhain was producing linear scales with accuracy of ± 15 µm and circular scale disks with accuracy of ± 3 angular seconds. After World War II, in 1948, Dr. Johannes Heidenhain, a pupil of Otto Hahn, founded the present company in Traunreut. Its invention of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
