Georgi Nadjakov
Georgi Nadjakov (also spelled Georgi Nadzhakov) ( bg, Георги Наджаков) (26 December 1896 – 24 February 1981) was a Bulgarian physicist. He became a corresponding member of the Göttingen Academy of Sciences (1940) in Germany, member of the Bulgarian Academy of Sciences (1945) and member of the Russian Academy of Sciences (1958). Sofia University sent him to specialize in the laboratories of Paul Langevin and Marie Curie in Paris, where he investigated photoelectricity for one year. Georgi Nadjakov experimentally investigated photoconducting properties of sulphur. He prepared the permanent photoelectret state of matter for the first time and published his paper in 1937 and 1938. He called the electret discovered by Mototaro Eguchi in 1919, thermoelectret and the electret discovered by him in 1937, photoelectret. Photoelectrets were the most notable achievement of Georgi Nadjakov. Its practical application led to the invention of the photocopier by Chester Carlso ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Dupnitsa
Dupnitsa, or Dupnica ( bg, Дупница (previously ), ), is a town in Western Bulgaria. It is at the foot of the highest mountains in the Balkan Peninsula – the Rila Mountains, and about south of the capital Sofia. Dupnitsa is the second largest town in Kyustendil Province. History The town has existed since ancient times. The German traveller Arnold von Harff visited Dupnitsa in 1499 and described it as a "beautiful town". The names ''Tobinitsa'', ''Doupla'' and ''Dubnitsa'' are mentioned throughout history, the last one used until the Liberation of Bulgaria, when the official name was changed to ''Dupnitsa''. In 1948 the town was renamed ''Stanke Dimitrov''; for a short period in 1949 it was called ''Marek''; the name was changed to ''Stanke Dimitrov'' in 1950. After the democratic changes, the old name ''Dupnitsa'' was restored. On 15 October 1902, around 600 women and children fled to the vicinity of Dupnitsa from Macedonia from the attacking Turkish troops. On a h ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Electret
An electret (formed as a portmanteau of ''electr-'' from "electricity" and ''-et'' from "magnet") is a dielectric material that has a quasi-permanent electric charge or dipole polarisation. An electret generates internal and external electric fields, and is the electrostatic equivalent of a permanent magnet. Although Oliver Heaviside coined this term in 1885, materials with electret properties were already known to science and had been studied since the early 1700s. One particular example is the electrophorus, a device consisting of a slab with electret properties and a separate metal plate. The electrophorus was originally invented by Johan Carl Wilcke in Sweden and again by Alessandro Volta in Italy. The name derives from "electron" and "magnet"; drawing analogy to the formation of a magnet by alignment of magnetic domains in a piece of iron. Historically, electrets were made by first melting a suitable dielectric material such as a polymer or wax that contains polar molecules, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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People From Dupnitsa
A person ( : people) is a being that has certain capacities or attributes such as reason, morality, consciousness or self-consciousness, and being a part of a culturally established form of social relations such as kinship, ownership of property, or legal responsibility. The defining features of personhood and, consequently, what makes a person count as a person, differ widely among cultures and contexts. In addition to the question of personhood, of what makes a being count as a person to begin with, there are further questions about personal identity and self: both about what makes any particular person that particular person instead of another, and about what makes a person at one time the same person as they were or will be at another time despite any intervening changes. The plural form "people" is often used to refer to an entire nation or ethnic group (as in "a people"), and this was the original meaning of the word; it subsequently acquired its use as a plural form of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bulgarian Physicists
Bulgarian may refer to: * Something of, from, or related to the country of Bulgaria * Bulgarians, a South Slavic ethnic group * Bulgarian language, a Slavic language * Bulgarian alphabet * A citizen of Bulgaria, see Demographics of Bulgaria * Bulgarian culture * Bulgarian cuisine, a representative of the cuisine of Southeastern Europe See also * * List of Bulgarians, include * Bulgarian name, names of Bulgarians * Bulgarian umbrella, an umbrella with a hidden pneumatic mechanism * Bulgar (other) * Bulgarian-Serbian War (other) The term Bulgarian-Serbian War or Serbian-Bulgarian War may refer to: * Bulgarian-Serbian War (839-842) * Bulgarian-Serbian War (853) * Bulgarian-Serbian wars (917-924) * Bulgarian-Serbian War (1330) * Bulgarian-Serbian War (1885) * Bulgarian-Serbi ... {{disambiguation Language and nationality disambiguation pages ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Members Of The Bulgarian Academy Of Sciences
Member may refer to: * Military jury, referred to as "Members" in military jargon * Element (mathematics), an object that belongs to a mathematical set * In object-oriented programming, a member of a class ** Field (computer science), entries in a database ** Member variable, a variable that is associated with a specific object * Limb (anatomy), an appendage of the human or animal body ** Euphemism for penis * Structural component of a truss, connected by nodes * User (computing), a person making use of a computing service, especially on the Internet * Member (geology), a component of a geological formation * Member of parliament * The Members, a British punk rock band * Meronymy, a semantic relationship in linguistics * Church membership, belonging to a local Christian congregation, a Christian denomination and the universal Church * Member, a participant in a club or learned society A learned society (; also learned academy, scholarly society, or academic association) is a ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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1981 Deaths
Events January * January 1 ** Greece enters the European Economic Community, predecessor of the European Union. ** Palau becomes a self-governing territory. * January 10 – Salvadoran Civil War: The Farabundo Martí National Liberation Front, FMLN launches its first major offensive, gaining control of most of Morazán Department, Morazán and Chalatenango Department, Chalatenango departments. * January 15 – Pope John Paul II receives a delegation led by Polish Solidarity (Polish trade union), Solidarity leader Lech Wałęsa at the Vatican City, Vatican. * January 20 – Iran releases the 52 Americans held for 444 days, minutes after Ronald Reagan is First inauguration of Ronald Reagan, sworn in as the 40th President of the United States, ending the Iran hostage crisis. * January 21 – The first DMC DeLorean, DeLorean automobile, a stainless steel sports car with gull-wing doors, rolls off the production line in Dunmurry, Northern Ireland. * January 24 – An 1981 Dawu ea ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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1896 Births
Events January–March * January 2 – The Jameson Raid comes to an end, as Jameson surrenders to the Boers. * January 4 – Utah is admitted as the 45th U.S. state. * January 5 – An Austrian newspaper reports that Wilhelm Röntgen has discovered a type of radiation (later known as X-rays). * January 6 – Cecil Rhodes is forced to resign as Prime Minister of the Cape of Good Hope, for his involvement in the Jameson Raid. * January 7 – American culinary expert Fannie Farmer publishes her first cookbook. * January 12 – H. L. Smith takes the first X-ray photograph. * January 17 – Fourth Anglo-Ashanti War: British redcoats enter the Ashanti capital, Kumasi, and Asantehene Agyeman Prempeh I is deposed. * January 18 – The X-ray machine is exhibited for the first time. * January 28 – Walter Arnold, of East Peckham, Kent, England, is fined 1 shilling for speeding at (exceeding the contemporary speed limit of , the first spee ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Institute Of Solid State Physics (Bulgaria)
Institute of Solid State Physics is one of the physical institutes at the Bulgarian Academy of Sciences, currently known as the Georgi Nadjakov Institute of Solid State Physics. It provides scientific background of solid state electronics and optics in Bulgaria. Some reports and discussions are referred to below. History Decree No 362 of 16 October 1972 by the Ministry Council of Bulgaria established the Institute of Solid State Physics as a successor of the Institute of Physics with Atomic Scientific Experimental Base at the Bulgarian Academy of Sciences, founded by Georgi Nadjakov in 1946. Since 16 February 1982 the Institute of Solid State Physics accepted the name "Georgi Nadjakov Institute of Solid State Physics". Milko Borissov professor, member of BAS is the first Director and creator of the Institute of Solid State Physics (1973–1991). Nikolay Kirov, professor, D.Sc. is the second Institute Director (1991–1999). Alexander G. Petrov, Professor, D. Sc., member of B ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Georgi Nadjakov Institute Of Solid State Physics
Institute of Solid State Physics is one of the physical institutes at the Bulgarian Academy of Sciences, currently known as the Georgi Nadjakov Institute of Solid State Physics. It provides scientific background of solid state electronics and optics in Bulgaria. Some reports and discussions are referred to below. History Decree No 362 of 16 October 1972 by the Ministry Council of Bulgaria established the Institute of Solid State Physics as a successor of the Institute of Physics with Atomic Scientific Experimental Base at the Bulgarian Academy of Sciences, founded by Georgi Nadjakov in 1946. Since 16 February 1982 the Institute of Solid State Physics accepted the name "Georgi Nadjakov Institute of Solid State Physics". Milko Borissov professor, member of BAS is the first Director and creator of the Institute of Solid State Physics (1973–1991). Nikolay Kirov, professor, D.Sc. is the second Institute Director (1991–1999). Alexander G. Petrov, Professor, D. Sc., member of B ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where vegetation o ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Graham Land
Graham Land is the portion of the Antarctic Peninsula that lies north of a line joining Cape Jeremy and Cape Agassiz. This description of Graham Land is consistent with the 1964 agreement between the British Antarctic Place-names Committee and the US Advisory Committee on Antarctic Names, in which the name "Antarctic Peninsula" was approved for the major peninsula of Antarctica, and the names Graham Land and Palmer Land for the northern and southern portions, respectively. The line dividing them is roughly 69 degrees south. Graham Land is named after Sir James R. G. Graham, First Lord of the Admiralty at the time of John Biscoe's exploration of the west side of Graham Land in 1832. It is claimed by Argentina (as part of Argentine Antarctica), Britain (as part of the British Antarctic Territory) and Chile (as part of the Chilean Antarctic Territory). Graham Land is the closest part of Antarctica to South America. Thus it is the usual destination for small ships taking paying ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Nadjakov Glacier
Nadjakov Glacier ( bg, Наджаков ледник, Nadzhakov lednik, ) is the 5.5 km long and 2 km wide glacier on Arctowski Peninsula on Danco Coast in Graham Land on the Antarctic Peninsula. Situated east of Wheatstone Glacier. Draining north-northeastwards to enter the head of Beaupré Cove east of Stolze Peak. The glacier is named after the Bulgarian physicist Georgi Nadjakov (1897–1981) who discovered the photoelectret state essential to modern photocopying. Location Nadjakov Glacier is located at . British mapping in 1980. Maps * British Antarctic Territory. Scale 1:200000 topographic map No. 3217. DOS 610 - W 64 62. Tolworth, UK, 1980. Antarctic Digital Database (ADD).Scale 1:250000 topographic map of Antarctica. Scientific Committee on Antarctic Research (SCAR). Since 1993, regularly upgraded and updated. References Bulgarian Antarctic Gazetteer.Antarctic Place-names Commission. (details in Bulgarianbasic datain English) Nadjakov Glacier.SCAR Composit ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |