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Saul Dushman
Saul Dushman (July 12, 1883 – July 7, 1954) was a Russian-American physical chemist. Dushman was born on July 12, 1883 in Rostov, Russia; he immigrated to the United States in 1891. He received a doctorate from the University of Toronto in 1912. That year, he joined the Research Laboratory of General Electric Company (GE). He would work at GE for the rest of his career except for a 1922-1925 stint as the Research Division director at Edison Lamp Works. His main research interests were quantum mechanics, electromotive force, atomic structure, electron emission, unimolecular force, and high vacuum, and he authored several standard science textbooks. His textbook "Scientific Foundations of Vacuum Technique" (1922 and 1949) is a classic covering vacuum design principles. This book and the later editions are still in use today. It was completely revised in 1961 by his colleague James Lafferty. His research on thermionic emission is remembered in the form of the Richardson ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Brunswick Marconi Station
New Brunswick Marconi Station was located at JFK Boulevard and Easton Avenue just one mile from the New Brunswick border in Somerset, New Jersey. History Ground was broken for the site on April 9, 1913, by the Marconi Wireless Telegraph Company of America. Although the station was completed in 1914 Marconi's planned commercial use for communication with his receiver station in Towyn, Wales never took place because of the onset of World War I but was finally initiated by RCA on March 1, 1920. The station served as a backup to RCA's primary transmitting station on Long Island until the antenna masts and transmitter building were demolished in 1952. The facility was confiscated by the United States government on April 7, 1917, the day after the United States declared war on Germany. The New Brunswick Naval Radio Station was the principal wartime radio communication link between the United States and Europe, using the callsign NFF. President Woodrow Wilson's Fourteen Points speech was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electromotive Force
In electromagnetism and electronics, electromotive force (also electromotance, abbreviated emf, denoted \mathcal or ) is an energy transfer to an electric circuit per unit of electric charge, measured in volts. Devices called electrical '' transducers'' provide an emf by converting other forms of energy into electrical energy. Other electrical equipment also produce an emf, such as batteries, which convert chemical energy, and generators, which convert mechanical energy. This energy conversion is achieved by physical forces applying physical work on electric charges. However, electromotive force itself is not a physical force, and for the current ISO/IEC standards consider the term deprecated, favoring the names source voltage or source tension instead (denoted U_s). An electronic–hydraulic analogy may view emf as the mechanical work done to water by a pump, which results in a pressure difference (analogous to voltage). In electromagnetic induction, emf can be defi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1954 Deaths
Events January * January 1 – The Soviet Union ceases to demand war reparations from West Germany. * January 3 – The Italian broadcaster RAI officially begins transmitting. * January 7 – Georgetown-IBM experiment: The first public demonstration of a machine translation system is held in New York, at the head office of IBM. * January 10 – BOAC Flight 781, a de Havilland Comet jet plane, disintegrates in mid-air due to metal fatigue, and crashes in the Mediterranean near Elba; all 35 people on board are killed. * January 12 – Avalanches in Austria kill more than 200. * January 15 – Mau Mau leader Waruhiu Itote is captured in Kenya. * January 17 – In Yugoslavia, Milovan Đilas, one of the leading members of the League of Communists of Yugoslavia, is relieved of his duties. * January 20 – The US-based National Negro Network is established, with 46 member radio stations. * January 21 – The first nuclear- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1883 Births
Events January–March * January 4 – ''Life'' magazine is founded in Los Angeles, California, United States. * January 10 – A fire at the Newhall Hotel in Milwaukee, Wisconsin, United States, kills 73 people. * January 16 – The Pendleton Civil Service Reform Act, establishing the United States civil service, is passed. * January 19 – The first electric lighting system employing overhead wires begins service in Roselle, New Jersey, United States, installed by Thomas Edison. * February – '' The Adventures of Pinocchio'' by Carlo Collodi is first published complete in book form, in Italy. * February 15 – Tokyo Electrical Lightning Grid, predecessor of Tokyo Electrical Power (TEPCO), one of the largest electrical grids in Asia and the world, is founded in Japan. * February 16 – The '' Ladies' Home Journal'' is published for the first time, in the United States. * February 23 – Alabama becomes the first U.S. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Physical Chemists
American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, people who self-identify their ancestry as "American" ** American English, the set of varieties of the English language native to the United States ** Native Americans in the United States, indigenous peoples of the United States * American, something of, from, or related to the Americas, also known as "America" ** Indigenous peoples of the Americas * American (word), for analysis and history of the meanings in various contexts Organizations * American Airlines, U.S.-based airline headquartered in Fort Worth, Texas * American Athletic Conference, an American college athletic conference * American Recordings (record label), a record label previously known as Def American * American University, in Washington, D.C. Sports teams Soccer * Ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Russian Physical Chemists
Russian(s) refers to anything related to Russia, including: *Russians (, ''russkiye''), an ethnic group of the East Slavic peoples, primarily living in Russia and neighboring countries *Rossiyane (), Russian language term for all citizens and people of Russia, regardless of ethnicity *Russophone, Russian-speaking person (, ''russkogovoryashchy'', ''russkoyazychny'') * Russian language, the most widely spoken of the Slavic languages * Russian alphabet * Russian cuisine *Russian culture *Russian studies Russian may also refer to: *Russian dressing *''The Russians'', a book by Hedrick Smith *Russian (comics), fictional Marvel Comics supervillain from ''The Punisher'' series *Russian (solitaire), a card game * "Russians" (song), from the album ''The Dream of the Blue Turtles'' by Sting *"Russian", from the album ''Tubular Bells 2003'' by Mike Oldfield *"Russian", from the album '' '' by Caravan Palace * Nik Russian, the perpetrator of a con committed in 2002 *The South African name f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richardson-Dushman Equation
Thermionic emission is the liberation of electrons from an electrode by virtue of its temperature (releasing of energy supplied by heat). This occurs because the thermal energy given to the charge carrier overcomes the work function of the material. The charge carriers can be electrons or ions, and in older literature are sometimes referred to as thermions. After emission, a charge that is equal in magnitude and opposite in sign to the total charge emitted is initially left behind in the emitting region. But if the emitter is connected to a battery, the charge left behind is neutralized by charge supplied by the battery as the emitted charge carriers move away from the emitter, and finally the emitter will be in the same state as it was before emission. The classical example of thermionic emission is that of electrons from a hot cathode into a vacuum (also known as thermal electron emission or the Edison effect) in a vacuum tube. The hot cathode can be a metal filament, a coated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermionic Emission
Thermionic emission is the liberation of electrons from an electrode by virtue of its temperature (releasing of energy supplied by heat). This occurs because the thermal energy given to the charge carrier overcomes the work function of the material. The charge carriers can be electrons or ions, and in older literature are sometimes referred to as thermions. After emission, a charge that is equal in magnitude and opposite in sign to the total charge emitted is initially left behind in the emitting region. But if the emitter is connected to a battery, the charge left behind is neutralized by charge supplied by the battery as the emitted charge carriers move away from the emitter, and finally the emitter will be in the same state as it was before emission. The classical example of thermionic emission is that of electrons from a hot cathode into a vacuum (also known as thermal electron emission or the Edison effect) in a vacuum tube. The hot cathode can be a metal filament, a coated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum
A vacuum is a space devoid of matter. The word is derived from the Latin adjective ''vacuus'' for "vacant" or " void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a ''perfect'' vacuum, which they sometimes simply call "vacuum" or free space, and use the term partial vacuum to refer to an actual imperfect vacuum as one might have in a laboratory or in space. In engineering and applied physics on the other hand, vacuum refers to any space in which the pressure is considerably lower than atmospheric pressure. The Latin term ''in vacuo'' is used to describe an object that is surrounded by a vacuum. The ''quality'' of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by around 20%. But h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Emission
In physics, electron emission is the ejection of an electron from the surface of matter, or, in beta decay (β− decay), where a beta particle (a fast energetic electron or positron) is emitted from an atomic nucleus transforming the original nuclide to an isobar. Radioactive decay * In Beta decay (β− decay), radioactive decay results in a beta particle (fast energetic electron or positron in β+ decay) being emitted from the nucleus Surface emission * Thermionic emission, the liberation of electrons from an electrode by virtue of its temperature ** Schottky emission, due to the: *** Schottky effect or field enhanced thermionic emission * Field electron emission, emission of electrons induced by an electrostatic field Devices * An electron gun or electron emitter, is an electrical component in some vacuum tubes that uses surface emission Others * Exoelectron emission, a weak electron emission, appearing only from pretreated objects * Photoelectric effect, the emis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Structure
Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics, as if they were tennis balls for example, is not possible due to quantum effects. More than 99.94% of an atom's mass is in the nucleus. The protons have a positive electric charge, the electrons have a negative electric charge, and the neutrons have no electric charge. If the number of protons and electrons are equal, then the atom is electrically neutral. If an atom has more or fewer electrons than protons, then it has an overall negative or positive charge, respectively – such atoms are called ions. The electrons of an atom are a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Mechanics
Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science. Classical physics, the collection of theories that existed before the advent of quantum mechanics, describes many aspects of nature at an ordinary (macroscopic) scale, but is not sufficient for describing them at small (atomic and subatomic) scales. Most theories in classical physics can be derived from quantum mechanics as an approximation valid at large (macroscopic) scale. Quantum mechanics differs from classical physics in that energy, momentum, angular momentum, and other quantities of a bound system are restricted to discrete values ( quantization); objects have characteristics of both particles and waves ( wave–particle duality); and there ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
