Nikolai Papaleksi
Nikolai Dmitrievich Papaleksi (20 November 1880 – 3 February 1947) was a physicist who pioneered radio technology and radio astronomy in the Soviet Union. He was involved in the discovery of radiowave emission by solar coronae in 1947. Early life Papaleksi was born in Simferopol in a family that produced many military officers. His father was a battalion commander in the 51st Lithuanian Regiment and the family may have had origins in Greece. He was educated locally at then at Poltava before he went to the Universities of Berlin and later Strasbourg where he met L. I. Mandelshtam. Together they studied radiowaves under Carl Ferdinand Braun who headed the Institute of Physics. Papaleksi received his doctorate in 1904. Career In 1906 Mandelshtam and Papaleksi worked on the production of high frequency radio waves. The worked for a while with the Telefunken company. In 1914 Papaleksi moved back to Russia due to World War I. He then worked on the production of gas triodes ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk ( Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Stellar Corona
A corona ( coronas or coronae) is the outermost layer of a star's atmosphere. It consists of plasma. The Sun's corona lies above the chromosphere and extends millions of kilometres into outer space. It is most easily seen during a total solar eclipse, but it is also observable with a coronagraph. Spectroscopic measurements indicate strong ionization in the corona and a plasma temperature in excess of , much hotter than the surface of the Sun, known as the photosphere. The word ''corona'' is , in turn derived . History In 1724, French-Italian astronomer Giacomo F. Maraldi recognized that the aura visible during a solar eclipse belongs to the Sun, not to the Moon. In 1809, Spanish astronomer José Joaquín de Ferrer coined the term 'corona'. Based in his own observations of the 1806 solar eclipse at Kinderhook (New York), de Ferrer also proposed that the corona was part of the Sun and not of the Moon. English astronomer Norman Lockyer identified the first element unknown o ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Simferopol
Simferopol () is the second-largest city in the Crimea, Crimean Peninsula. The city, along with the rest of Crimea, is internationally recognised as part of Ukraine, and is considered the capital of the Autonomous Republic of Crimea. However, it is under the ''de facto'' control of Russia, which Annexation of Crimea by the Russian Federation, annexed Crimea in 2014 and regards Simferopol as the capital of the Republic of Crimea. Simferopol is an important political, economic and transport hub of the peninsula, and serves as the administrative centre of both Simferopol Municipality and the surrounding Simferopol District. After the 1784 Annexation of Crimea by the Russian Empire, annexation of the Crimean Khanate by the Russian Empire, the Russian empress decreed the foundation of the city with the name Simferopol on the location of the Crimean Tatars, Crimean Tatar town of Aqmescit ("White Mosque"). The population was Etymologies The name Simferopol ( uk, Сімферо́ ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Poltava
Poltava (, ; uk, Полтава ) is a city located on the Vorskla River in central Ukraine. It is the capital city of the Poltava Oblast (province) and of the surrounding Poltava Raion (district) of the oblast. Poltava is administratively incorporated as a city of oblast significance and does not belong to the raion. It has a population of History It is still unknown when Poltava was founded, although the town was not attested before 1174. However, for reasons unknown, municipal authorities chose to celebrate the city's 1100th anniversary in 1999. The settlement is indeed an old one, as archeologists unearthed a Paleolithic dwelling as well as Scythian remains within the city limits. Middle Ages The present name of the city is traditionally connected to the settlement Ltava which is mentioned in the Hypatian Chronicle in 1174. [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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University Of Strasbourg
The University of Strasbourg (french: Université de Strasbourg, Unistra) is a public research university located in Strasbourg, Alsace, France, with over 52,000 students and 3,300 researchers. The French university traces its history to the earlier German-language ''Universität Straßburg'', which was founded in 1538, and was divided in the 1970s into three separate institutions: Louis Pasteur University, Marc Bloch University, and Robert Schuman University. On 1 January 2009, the fusion of these three universities reconstituted a united University of Strasbourg. With as many as 19 Nobel laureates, and two Fields Medal winners, the university is ranked among the best in the League of European Research Universities. History The university emerged from a Lutheran humanist German Gymnasium, founded in 1538 by Johannes Sturm in the Free Imperial City of Strassburg. It was transformed to a university in 1621 (german: Universität Straßburg) and elevated to the ranks of a royal u ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Leonid Mandelstam
Leonid Isaakovich Mandelstam or Mandelshtam ( be, Леанід Ісаакавіч Мандэльштам; rus, Леонид Исаакович Мандельштам, p=lʲɪɐˈnʲit ɨsɐˈakəvʲɪtɕ mənʲdʲɪlʲˈʂtam, a=Ru-Leonid_Mandelstam.ogg, links=y; 4 May 1879 – 27 November 1944) was a Soviet physicist of Belarusian-Jewish background. Life Leonid Mandelstam was born in Mogilev, Russian Empire (now Belarus). He studied at the Novorossiya University in Odessa, but was expelled in 1899 due to political activities, and continued his studies at the University of Strasbourg. He remained in Strasbourg until 1914, and returned with the beginning of World War I. He was awarded the Stalin Prize in 1942. Mandelstam died in Moscow, USSR (now Russia). Scientific achievements The main emphasis of his work was broadly considered theory of oscillations, which included optics and quantum mechanics. He was a co-discoverer of inelastic ''combinational scattering of light'' ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Karl Ferdinand Braun
Karl Ferdinand Braun (; 6 June 1850 – 20 April 1918) was a German electrical engineer, inventor, physicist and Nobel laureate in physics. Braun contributed significantly to the development of radio and television technology: he shared the 1909 Nobel Prize in Physics with Guglielmo Marconi "for their contributions to the development of wireless telegraphy", was a founder of Telefunken, one of the pioneering communications and television companies, and has been both called the "father of television" (shared with inventors like Paul Gottlieb Nipkow) and the co-father of the radio telegraphy, together with Marconi. Biography Braun was born in Fulda, Germany, and educated at the University of Marburg and received a PhD from the University of Berlin in 1872. In 1874, he discovered that a point-contact metal–semiconductor junction rectifies alternating current. He became director of the Physical Institute and professor of physics at the University of Strassburg in 1895. In 189 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Telefunken
Telefunken was a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the ''Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ('General electricity company'). The name "Telefunken" appears in: * the product brand name "Telefunken"; * ''Gesellschaft für drahtlose Telegraphie m.b.H., System Telefunken'', founded 1903 in Berlin as a subsidiary of AEG and Siemens & Halske; * ''Telefunken, Gesellschaft für drahtlose Telegraphie m.b.H.'' (from 1923 to 1955 – since 1941 subsidiary of the AEG only); * ''Telefunken GmbH'' in 1955; * ''Telefunken Aktiengesellschaft (AG)'' in 1963; * Merger of AEG and Telefunken to form ''Allgemeine Elektrizitäts-Gesellschaft AEG-Telefunken'' (from 1967 to 1979); * AEG-TELEFUNKEN AG (from 1979 to 1985); * ''TELEFUNKEN Fernseh und Rundfunk GmbH'', Hanover (1972, subsidiary of AEG-TELEFUNKEN); * Telefunken electronic GmbH (a spin-off of AEG-Telefunken and DASA * the company (since 1992 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fighting occurring throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia. An estimated 9 million soldiers were killed in combat, plus another 23 million wounded, while 5 million civilians died as a result of military action, hunger, and disease. Millions more died in genocides within the Ottoman Empire and in the 1918 influenza pandemic, which was exacerbated by the movement of combatants during the war. Prior to 1914, the European great powers were divided between the Triple Entente (comprising France, Russia, and Britain) and the Triple Alliance (containing Germany, Austria-Hungary, and Italy). Tensions in the Balkans came to a head on 28 June 1914, following the assassination of Archduke Franz Ferdin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Triode
A triode is an electronic amplifying vacuum tube (or ''valve'' in British English) consisting of three electrodes inside an evacuated glass envelope: a heated filament or cathode, a grid, and a plate (anode). Developed from Lee De Forest's 1906 Audion, a partial vacuum tube that added a grid electrode to the thermionic diode (Fleming valve), the triode was the first practical electronic amplifier and the ancestor of other types of vacuum tubes such as the tetrode and pentode. Its invention founded the electronics age, making possible amplified radio technology and long-distance telephony. Triodes were widely used in consumer electronics devices such as radios and televisions until the 1970s, when transistors replaced them. Today, their main remaining use is in high-power RF amplifiers in radio transmitters and industrial RF heating devices. In recent years there has been a resurgence in demand for low power triodes due to renewed interest in tube-type audio systems by audiophi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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1880 Births
Year 188 (CLXXXVIII) was a leap year starting on Monday of the Julian calendar. At the time, it was known in the Roman Empire as the Year of the Consulship of Fuscianus and Silanus (or, less frequently, year 941 ''Ab urbe condita''). The denomination 188 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Publius Helvius Pertinax becomes pro-consul of Africa from 188 to 189. Japan * Queen Himiko (or Shingi Waō) begins her reign in Japan (until 248). Births * April 4 – Caracalla (or Antoninus), Roman emperor (d. 217) * Lu Ji (or Gongji), Chinese official and politician (d. 219) * Sun Shao, Chinese general of the Eastern Wu state (d. 241) Deaths * March 17 – Julian, pope and patriarch of Alexandria * Fa Zhen (or Gaoqing), Chinese scholar (b. AD 100) * Lucius Antistius Burrus, Roman politician (executed) * Ma Xiang, Chin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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1947 Deaths
It was the first year of the Cold War, which would last until 1991, ending with the dissolution of the Soviet Union. Events January * January–February – Winter of 1946–47 in the United Kingdom: The worst snowfall in the country in the 20th century causes extensive disruption of travel. Given the low ratio of private vehicle ownership at the time, it is mainly remembered in terms of its effects on the railway network. * January 1 - The Canadian Citizenship Act comes into effect. * January 4 – First issue of weekly magazine ''Der Spiegel'' published in Hanover, Germany, edited by Rudolf Augstein. * January 10 – The United Nations adopts a resolution to take control of the free city of Trieste. * January 15 – Elizabeth Short, an aspiring actress nicknamed the "Black Dahlia", is found brutally murdered in a vacant lot in Los Angeles; the mysterious case is never solved. * January 16 – Vincent Auriol is inaugurated as president of France. * January 19 – Ferry ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |