HOME



picture info

Fleming Valve
The Fleming valve, also called the Fleming oscillation valve, was a thermionic valve or vacuum tube invented in 1904 by English physicist John Ambrose Fleming as a detector for early radio receivers used in electromagnetic wireless telegraphy. It was the first practical vacuum tube and the first thermionic diode, a vacuum tube whose purpose is to conduct current in one direction and block current flowing in the opposite direction. The thermionic diode was later widely used as a rectifier — a device that converts alternating current (AC) into direct current (DC) — in the power supplies of a wide range of electronic devices, until beginning to be replaced by the selenium rectifier in the early 1930s and almost completely replaced by the semiconductor diode in the 1960s. The Fleming valve was the forerunner of all vacuum tubes, which dominated electronics for 50 years. The IEEE has described it as "one of the most important developments in the history of electroni ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Fleming Valves
Fleming may refer to: Places Australia *Fleming, Northern Territory, a town and a locality Canada * Fleming, Saskatchewan * Fleming Island (Saskatchewan) Egypt * Fleming (neighborhood), a neighborhood in Alexandria Greenland * Fleming Fjord Italy * Fleming (Rome), a neighborhood United States * Fleming, Colorado * Fleming, Georgia * Fleming, Kansas * Fleming, Kentucky, a predecessor of Fleming-Neon, Kentucky, in Letcher County * Fleming County, Kentucky * Fleming, Missouri * Fleming, New York * Fleming, Ohio People * Fleming (surname) * Flemings, demonym for the Flemish people of Flanders, Belgium * Clan Fleming, a Scottish clan * Fleming (noble family), a Finnish noble family Other uses * Fleming (crater), a lunar crater * Fleming Building, a building in Des Moines, Iowa, United States * Fleming College, a college in Peterborough, Ontario, Canada * Fleming Companies, Inc, an American food supply company * , more than one United States Navy ship * '' Fleming: The ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Edison Effect
Thermionic emission is the liberation of charged particles from a hot electrode whose thermal energy gives some particles enough kinetic energy to escape the material's surface. The particles, sometimes called ''thermions'' in early literature, are now known to be ions or electrons. Thermal electron emission specifically refers to emission of electrons and occurs when thermal energy overcomes the material's work function. After emission, an opposite charge of equal magnitude to the emitted charge is initially left behind in the emitting region. But if the emitter is connected to a battery, that remaining charge is neutralized by charge supplied by the battery as particles are emitted, so the emitter will have the same charge it had before emission. This facilitates additional emission to sustain an electric current. Thomas Edison in 1880 while inventing his light bulb noticed this current, so subsequent scientists referred to the current as the Edison effect, though it wasn't un ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Thomas Edison
Thomas Alva Edison (February11, 1847October18, 1931) was an American inventor and businessman. He developed many devices in fields such as electric power generation, mass communication, sound recording, and motion pictures. These inventions, which include the phonograph, the motion picture camera, and early versions of the electric Incandescent light bulb, light bulb, have had a widespread impact on the modern industrial society, industrialized world. He was one of the first inventors to apply the principles of organized science and teamwork to the process of invention, working with many researchers and employees. He established the first industrial research laboratory. Edison was raised in the American Midwest. Early in his career he worked as a telegraph operator, which inspired some of his earliest inventions. In 1876, he established his first laboratory facility in Menlo Park, New Jersey, where many of his early inventions were developed. He later established a botanical ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Incandescent Lamp
An incandescent light bulb, also known as an incandescent lamp or incandescent light globe, is an electric light that produces illumination by Joule heating a filament until it glows. The filament is enclosed in a glass bulb that is either evacuated or filled with inert gas to protect the filament from oxidation. Electric current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections. Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment, have low manufacturing costs, and work equally well on either alternating current or direct current. As a result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, and for decorative and advertising lighting. Incandescent b ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Frederick Guthrie (scientist)
Frederick Guthrie FRS FRSE (15 October 1833 – 21 October 1886) was a British physicist, chemist, and academic author. He was the son of Alexander Guthrie, a London tradesman, and the younger brother of mathematician Francis Guthrie. Along with William Fletcher Barrett he founded the Physical Society of London (now the Institute of Physics) in 1874 and was president of the society from 1884 until 1886. He believed that science should be based on experimentation rather than discussion. Academic career His academic career started at University College, London, where he studied for three years. He studied chemistry under Thomas Graham and Alexander William Williamson and mathematics under Augustus De Morgan. In 1852, he submitted his brother Francis's observations to De Morgan. In 1854 Guthrie went to Heidelberg to study under Robert Bunsen and then in 1855 obtained a PhD at the University of Marburg under Adolph Wilhelm Hermann Kolbe. In 1856 he joined Edward Frankland ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Thermionic Emission
Thermionic emission is the liberation of charged particles from a hot electrode whose thermal energy gives some particles enough kinetic energy to escape the material's surface. The particles, sometimes called ''thermions'' in early literature, are now known to be ions or electrons. Thermal electron emission specifically refers to emission of electrons and occurs when thermal energy overcomes the material's work function. After emission, an opposite charge of equal magnitude to the emitted charge is initially left behind in the emitting region. But if the emitter is connected to a battery, that remaining charge is neutralized by charge supplied by the battery as particles are emitted, so the emitter will have the same charge it had before emission. This facilitates additional emission to sustain an electric current. Thomas Edison in 1880 while inventing his light bulb noticed this current, so subsequent scientists referred to the current as the Edison effect, though it wasn't un ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Electron
The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary charge, elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up quark, up and down quark, down quarks. Electrons are extremely lightweight particles that orbit the positively charged atomic nucleus, nucleus of atoms. Their negative charge is balanced by the positive charge of protons in the nucleus, giving atoms their overall electric charge#Charge neutrality, neutral charge. Ordinary matter is composed of atoms, each consisting of a positively charged nucleus surrounded by a number of orbiting electrons equal to the number of protons. The configuration and energy levels of these orbiting electrons determine the chemical properties of an atom. Electrons are bound to the nucleus to different degrees. The outermost or valence electron, valence electrons are the least tightly bound and are responsible for th ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Plate Electrode
Plate may refer to: Cooking * Plate (dishware), broad, mainly flat vessel commonly used to serve food * Plates, tableware, dishes or dishware used for setting a table, serving food and dining * Plate, the content of such a plate (for example: rice plate) * Plate, to present food, on a plate * Plate, forequarter cut of beef Places * Plate, Germany, municipality in Parchim, Mecklenburg-Vorpommern, Germany * Plate, borough of Lüchow, Lower Saxony, Germany * River Plate (other) * Tourelle de la Plate, lighthouse in France Science and technology Biology and medicine * Plate (anatomy), several meanings * Dental plate, also known as dentures * Dynamic compression plate, metallic plate used in orthopedics to fix bone * Microtiter plate (or microplate or microwell plate), flat plate with multiple "wells" used as small test tubes * Orthopedic plate, internal fixation used in orthopaedic surgery * Petri dish or Petri plate, shallow dish on which biological ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Anode
An anode usually is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, which is usually an electrode of the device through which conventional current leaves the device. A common mnemonic is ACID, for "anode current into device". The direction of conventional current (the flow of positive charges) in a circuit is opposite to the direction of electron flow, so (negatively charged) electrons flow from the anode of a galvanic cell, into an outside or external circuit connected to the cell. For example, the end of a household battery marked with a "+" is the cathode (while discharging). In both a galvanic cell and an electrolytic cell, the anode is the electrode at which the oxidation reaction occurs. In a galvanic cell the anode is the wire or plate having excess negative charge as a result of the oxidation reaction. In an electrolytic cell, the anode is the wire or plate upon which excess positive charge ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Electrical Filament
An incandescent light bulb, also known as an incandescent lamp or incandescent light globe, is an electric light that produces illumination by Joule heating a filament until it glows. The filament is enclosed in a glass bulb that is either evacuated or filled with inert gas to protect the filament from oxidation. Electric current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections. Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment, have low manufacturing costs, and work equally well on either alternating current or direct current. As a result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, and for decorative and advertising lighting. Incandescent bu ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cathode
A cathode is the electrode from which a conventional current leaves a polarized electrical device such as a lead-acid battery. This definition can be recalled by using the mnemonic ''CCD'' for ''Cathode Current Departs''. Conventional current describes the direction in which positive charges move. Electrons, which are the carriers of current in most electrical systems, have a negative electrical charge, so the movement of electrons is ''opposite'' to that of the conventional current flow: this means that electrons flow ''into'' the device's cathode from the external circuit. For example, the end of a household battery marked with a + (plus) is the cathode. The electrode through which conventional current flows the other way, into the device, is termed an anode. Charge flow Conventional current flows from cathode to anode outside the cell or device (with electrons moving in the opposite direction), regardless of the cell or device type and operating mode. Cathode polarity ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]