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Wilhelm Hanle
Wilhelm Hanle (13 January 1901 – 29 April 1993) was a German experimental physicist. He is known for the Hanle effect. During World War II, he made contributions to the German nuclear energy project, also known as the Uranium Club. From 1941 until ''emeritus'' status in 1969, he was an ordinarius professor of experimental physics and held the chair of physics at the University of Giessen. Education Hanle was born in Mannheim. From 1919 to 1924, he studied at the Ruprecht-Karls-Universität Heidelberg and the Georg-August-Universität Göttingen. Philipp Lenard, Director of the Physikalische Institut (Physics Institute) at Heidelberg, had a dictatorial attitude towards his students and colleagues, and Hanle had a conflict with Lenard. Hanle transferred to Göttingen. In 1923, Hanle conducted an experiment which demonstrated the variation of polarization of the resonance fluorescent light from a mercury vapor in a weak magnetic field; this became known as the "Hanle effect".A. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannheim
Mannheim (; Palatine German language, Palatine German: or ), officially the University City of Mannheim (), is the List of cities in Baden-Württemberg by population, second-largest city in Baden-Württemberg after Stuttgart, the States of Germany, state capital, and Germany's List of cities in Germany by population, 21st-largest city, with a population of over 315,000. It is located at the border with Rhineland-Palatinate. The city is the cultural and economic centre of the Rhine-Neckar, Germany's Metropolitan regions in Germany, seventh-largest metropolitan region, with nearly 2.4 million inhabitants. Mannheim is located at the confluence of the Upper Rhine and the Neckar in the Kurpfalz (region), Kurpfalz (Electoral Palatinate) region of northwestern Baden-Württemberg. The city lies in the Upper Rhine Plain, Germany's warmest region, between the Palatine Forest and the Oden Forest. Mannheim forms a continuous urban zone of around 500,000 inhabitants with Ludwigshafen am Rhe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philipp Lenard
Philipp Eduard Anton von Lenard (; ; 7 June 1862 – 20 May 1947) was a Hungarian-German physicist who received the Nobel Prize in Physics in 1905 "for his work on cathode rays" and the discovery of many of their properties. One of his most important contributions was the experimental realization of the photoelectric effect. He discovered that the energy (speed) of the electrons ejected from a cathode depends only on the frequency, and not the intensity, of the incident light. Lenard was a nationalist and antisemite; as an active proponent of the Nazi ideology, he supported Adolf Hitler in the 1920s and was an important role model for the movement during the Nazi period. Notably, he labeled Albert Einstein's contributions to science as "Jewish physics". Early life and work Philipp Lenard was born in Pressburg (''Pozsony'', today's Bratislava), on 7 June 1862 in the Kingdom of Hungary. The Lenard family had originally come from Tyrol in the 17th century, while his mother' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutrons
The neutron is a subatomic particle, symbol or , that has no electric charge, and a mass slightly greater than that of a proton. The neutron was discovered by James Chadwick in 1932, leading to the discovery of nuclear fission in 1938, the first self-sustaining nuclear reactor (Chicago Pile-1, 1942) and the first nuclear weapon (Trinity, 1945). Neutrons are found, together with a similar number of protons in the nuclei of atoms. Atoms of a chemical element that differ only in neutron number are called isotopes. Free neutrons are produced copiously in nuclear fission and fusion. They are a primary contributor to the nucleosynthesis of chemical elements within stars through fission, fusion, and neutron capture processes. Neutron stars, formed from massive collapsing stars, consist of neutrons at the density of atomic nuclei but a total mass more than the Sun. Neutron properties and interactions are described by nuclear physics. Neutrons are not elementary particles; each is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium
Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium radioactive decay, radioactively decays, usually by emitting an alpha particle. The half-life of this decay varies between 159,200 and 4.5 billion years for different isotopes of uranium, isotopes, making them useful for dating the age of the Earth. The most common isotopes in natural uranium are uranium-238 (which has 146 neutrons and accounts for over 99% of uranium on Earth) and uranium-235 (which has 143 neutrons). Uranium has the highest atomic weight of the primordial nuclide, primordially occurring elements. Its density is about 70% higher than that of lead and slightly lower than that of gold or tungsten. It occurs naturally in low concentrations of a few Parts-per notation#Parts-per expressions, parts per million in soil, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barium
Barium is a chemical element; it has symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. The most common minerals of barium are barite ( barium sulfate, BaSO4) and witherite ( barium carbonate, BaCO3). The name ''barium'' originates from the alchemical derivative "baryta", from Greek (), meaning 'heavy'. ''Baric'' is the adjectival form of barium. Barium was identified as a new element in 1772, but not reduced to a metal until 1808 with the advent of electrolysis. Barium has few industrial applications. Historically, it was used as a getter for vacuum tubes and in oxide form as the emissive coating on indirectly heated cathodes. It is a component of YBCO (high-temperature superconductors) and electroceramics, and is added to steel and cast iron to reduce the size of carbon grains within the microstructure. Barium compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Die Naturwissenschaften
''The Science of Nature'', formerly ''Naturwissenschaften'', is a monthly peer-reviewed scientific journal published by Springer Science+Business Media covering all aspects of the natural sciences relating to questions of biological significance. It was founded in 1913 and intended as a German-language equivalent of the English-language journal ''Nature'', at a time when German was still a dominant language of the natural sciences. The journal is now published in English. History ''Die Naturwissenschaften'' was founded in 1913 by Arnold Berliner and published by Julius Springer Verlag. Berliner intended to create a German equivalent to the English-language journal ''Nature''. The original subtitle ''Wochenschrift für die Fortschritte der Naturwissenschaften, der Medizin und der Technik'' (''Weekly Publication of the Advances in the Natural Sciences, Medicine and Technology'') was later changed to its current ''The Science of Nature''. The journal is published monthly and the art ... [...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 Robert Frisch. In their second publication on nuclear fission in February 1939, Strassmann and Hahn predicted the existence and liberation of additional neutrons during the fission process, opening up the possibility of a nuclear chain reaction. Early life Friedrich Wilhelm (Fritz) Strassmann was born in Boppard, Germany, to Richard Strassmann 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 modes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Hahn
Otto Hahn (; 8 March 1879 – 28 July 1968) was a German chemist who was a pioneer in the field of radiochemistry. He is referred to as the father of nuclear chemistry and discoverer of nuclear fission, the science behind nuclear reactors and nuclear weapons. Hahn and Lise Meitner discovered isotopes of the radioactive elements isotopes of radium, radium, Isotopes of thorium, thorium, isotopes of protactinium, protactinium and isotopes of uranium, uranium. He also discovered the phenomena of atomic recoil and nuclear isomerism, and pioneered rubidium–strontium dating. In 1938, Hahn, Meitner and Fritz Strassmann Discovery of nuclear fission, discovered nuclear fission, for which Hahn alone was awarded the 1944 Nobel Prize in Chemistry. A graduate of the University of Marburg, which awarded him a doctorate in 1901, Hahn studied under Sir William Ramsay at University College London and at McGill University in Montreal under Ernest Rutherford, where he discovered several new radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
German Nuclear Energy Project
Nazi Germany undertook several research programs relating to nuclear technology, including nuclear weapons and nuclear reactors, before and during World War II. These were variously called () or (). The first effort started in April 1939, just months after the discovery of nuclear fission in Berlin in December 1938, but ended shortly ahead of the September 1939 German invasion of Poland, for which many German physicists were drafted into the . A second effort under the administrative purview of the 's began on September 1, 1939, the day of the invasion of Poland. The program eventually expanded into three main efforts: (nuclear reactor) development, uranium and heavy water production, and uranium isotope separation. Eventually, the German military determined that nuclear fission would not contribute significantly to the war, and in January 1942 the turned the program over to the Reich Research Council () while continuing to fund the activity. The program was split up among ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Law For The Restoration Of The Professional Civil Service
The Law for the Restoration of the Professional Civil Service (, shortened to ''Berufsbeamtengesetz''), also known as Civil Service Law, Civil Service Restoration Act, and Law to Re-establish the Civil Service, was enacted by the Nazi Party, Nazi regime in Nazi Germany, Germany on 7 April 1933. This law, which followed Adolf Hitler's rise to power by two months and the promulgation of the Enabling Act of 1933, Enabling Act by two weeks, constituted one of the earliest instances of anti-Semitic and racist legislation in Germany. The primary objective of the law was to establish a "national" and "professional" civil service by dismissing certain groups of tenured civil servants. Individuals of non-Aryan race, Aryan origin, particularly those of Jews, Jewish descent, were compelled to retire, while members of the Communist party, Communist Party or affiliated organizations were to be terminated from their positions. Additionally, the law forbade Jews, non-Aryans, and political oppo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Joos
Georg Jakob Christof Joos (25 May 1894 in Bad Urach, German Empire – 20 May 1959 in Munich, West Germany) was a German experimental physicist. He wrote ''Lehrbuch der theoretischen Physik'', first published in 1932 and one of the most influential theoretical physics textbooks of the 20th Century. Education Joos began his higher education in 1912 at the Technische Hochschule Stuttgart. He then went to study at the University of Tübingen, where he received his doctorate in 1920 under C. Füchtbauer.Hentschel, 1996, Appendix F; see the entry for Joos. Career After receipt of his doctorate, Joos became a teaching assistant to Jonathan Zenneck at the Technical University of Munich. In 1922, he became a Privatdozent there.Author Catalog: Joos – American Philosophical Society In 1924, he was appointed extr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ausserordentlicher Professor
Academic ranks in Germany are the titles, relative importance and power of professors, researchers, and administrative personnel held in academia. Overview Appointment grades * (Pay grade: ''W3'' or ''W2'') * (''W3'') * (''W2'') * (''W2'', only in ''Baden-Württemberg'') – although paid like a professor appointed at level W2, lecturers in this position do not have a professor title; the term was formerly used in all states for senior lecturer positions with research and teaching responsibilities (''C2'', being phased out since 2002) * (not tenured, but increasingly with tenure track) (''W1'') * (not tenured) (''W1'', only in ''Baden-Württemberg'') * or (''A13'', ''A14'', ''A15'') * (''TVöD 13/14/15'', ''TvL 13/14/15'') * (''TVöD'', ''TvL'' ''A13 a. Z.'') * (''TVöD'', only in ''Baden-Württemberg'') * (''TdL'') * (''TdL'') Non-appointment grades * * – conferred, in some German states, to a ''Privatdozent'' who has been in scientific service for several year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
