- Garter, The Most Noble Order of the (English knighthood)
The Most Noble Order of the Garter, English order of knighthood founded by King Edward III in 1348, ranked as the highest British civil and military honour obtainable. Because the earliest records of the order were destroyed by fire, it is difficult for historians to be certain of its original
- Garthorne, George (English silversmith)
chocolate pot: …made by the English silversmith George Garthorne. The drinking of chocolate in coffee houses was very fashionable during the last quarter of the 17th and the first quarter of the 18th century, but by the middle of the century it had fallen out of favour.
- Gärtner, Friedrich von (German architect)
Western architecture: Germany and Austria: …architects Leo von Klenze and Friedrich von Gärtner into a major cultural capital. Their twin models were Periclean Athens and Renaissance Florence, the former providing the inspiration for Klenze’s Greek Doric Ruhmeshalle (1843–54) and Propylaeon (1846–60) and the latter for Gärtner’s Bavarian State Library (1832–43). The most poetic product of…
- Gartner, Mike (Canadian hockey player)
Washington Capitals: Right wing Mike Gartner and defensemen Larry Murphy and Rod Langway led the team to five consecutive second-place divisional finishes between 1983–84 and 1987–88. Washington won its first division title in 1988–89 and appeared in the conference finals in 1989–90, but the Capitals failed to advance any…
- Gartok (China)
Gartok, town, western Tibet Autonomous Region, western China. It is located at an elevation of 14,630 feet (4,460 metres) at the foot of the Kailas Range (Gangdisi Shan) on the Gar River, which is one of the headwaters of the Indus River (in Tibet Sindhu, or Yindu, River). Gartok is an important
- Garua (Cameroon)
Garoua, town located in northeastern Cameroon. The town lies along the right bank of the Benue River, north-northeast of Yaoundé, the national capital. It is situated at the junction of the road between Maroua and Ngaoundéré and the Benue waterway and is the chief commercial centre of the region.
- garúa (meteorology)
Lima: Climate: …throughout the winter, and the garúa (dense sea mist) often rolls in to blanket areas of the city. Precipitation, which rarely exceeds 2 inches (50 mm) per annum, usually results from the condensation of the garúa. Lima is perhaps best described as cold and damp in winter and hot and…
- Garuda (Hindu mythology)
Garuda, in Hindu mythology, the bird (a kite or an eagle) and the vahana (mount) of the god Vishnu. In the Rigveda the sun is compared to a bird in its flight across the sky, and an eagle carries the ambrosial soma plant from heaven to earth. The mythological account of Garuda’s birth in the
- garum (sauce)
cooking: Ancient Rome: …today would be considered desserts—included garum, a fermented fish sauce similar to Asian fish sauce and thought to be an early predecessor of Worcestershire sauce. The Romans added that fish sauce to nearly everything, but it does not appear in Italian recipes today. Romans also used lovage (an herb) extensively,…
- Garusi (anthropological and archaeological site, Tanzania)
Laetoli, site of paleoanthropological excavations in northern Tanzania about 40 km (25 miles) from Olduvai Gorge, another major site. Mary Leakey and coworkers discovered fossils of Australopithecus afarensis at Laetoli in 1978, not far from where a group of hominin (of human lineage) fossils had
- Garvey movement (United States)
African Americans: The Garvey movement and the Harlem Renaissance: The Garvey movement was characterized by colorful pageantry and appeals for the rediscovery of African heritage. Its goal was to establish an independent Africa through the return of a revolutionary vanguard of African Americans. Garvey’s great attraction among poor African Americans was not matched, however, among…
- Garvey, Marcus (Jamaican Black nationalist leader)
Marcus Garvey was a charismatic Black leader who organized the first important American Black nationalist movement (1919–26), based in New York City’s Harlem. Largely self-taught, Garvey attended school in Jamaica until he was 14. After traveling in Central America and living in London from 1912 to
- Garvey, Marcus Mosiah (Jamaican Black nationalist leader)
Marcus Garvey was a charismatic Black leader who organized the first important American Black nationalist movement (1919–26), based in New York City’s Harlem. Largely self-taught, Garvey attended school in Jamaica until he was 14. After traveling in Central America and living in London from 1912 to
- Garvey, Steve (American baseball player)
San Diego Padres: …1984 Gwynn and fellow all-stars Steve Garvey and Rich (“Goose”) Gossage led the Padres to their first division title, which they followed with a five-game victory over the Chicago Cubs in the NL Championship Series (NLCS) to earn their first World Series berth. At the World Series the Padres faced…
- Garvin, J. L. (British editor)
Encyclopædia Britannica: Thirteenth edition: …had died and Cox chose J.L. Garvin (1868–1947), editor of The Observer, as London editor.
- Garwyn of Powys, Cynan (Welsh hero)
Celtic literature: The Middle Ages: …a poem in praise of Cynan Garwyn of Powys, whose son Selyf was slain in battle. This poem struck a note that remained constant in all Welsh eulogies and elegies down to the fall of the Welsh bardic system: Cynan is the bravest in the field, the most generous in…
- Gary (Indiana, United States)
Gary, city, Lake county, extreme northwest Indiana, U.S. It lies at the southern end of Lake Michigan, east of Chicago. In 1906 the town—named for Elbert H. Gary, chief organizer of the United States Steel Corporation—was laid out as an adjunct of the company’s vast new manufacturing complex. The
- Gary Plan (education)
Gary Plan, an educational system instituted in 1907 in Gary, Indiana. It was part of the larger scientific management movement in the early part of the 20th century that tried to increase efficiency in manufacturing through increased separation of worker roles and duties as well as through
- Gary, Elbert Henry (American jurist)
Elbert Henry Gary was a U.S. jurist and the chief organizer of the United States Steel Corporation. In 1871 Gary entered law practice in Chicago. He served as judge of Du Page County, Ill., from 1882 to 1890 and was president of the Chicago Bar Association from 1893 to 1894. A leader and an
- Gary, Romain (French author)
Romain Gary was a Lithuanian-born French novelist whose first work, L’Éducation européenne (1945; Forest of Anger), won him immediate acclaim. Humanistic and optimistic despite its graphic depictions of the horrors of World War II, the novel was later revised and reissued in English as Nothing
- Gary: A Sequel to Titus Andronicus (play by Mac)
Nathan Lane: Stage productions: …in the Broadway production of Gary: A Sequel to Titus Andronicus, a dark comedy set in the aftermath of William Shakespeare’s first tragedy.
- Garyān (Libya)
Gharyān, town, in the Tripolitania region of northwestern Libya. It lies at the foot of the plateau Jabal Nafūsah, 50 miles (80 km) south of Tripoli, and was a major centre of Italian colonization in the early 1910s. After the Turko-Italian war (1911–12) and the defeat of Turkey, the Gebel, Berber,
- Garyarsa (China)
Gartok, town, western Tibet Autonomous Region, western China. It is located at an elevation of 14,630 feet (4,460 metres) at the foot of the Kailas Range (Gangdisi Shan) on the Gar River, which is one of the headwaters of the Indus River (in Tibet Sindhu, or Yindu, River). Gartok is an important
- Garza, Matt (American baseball player)
Tampa Bay Rays: …of young stars Scott Kazmir, Matt Garza, Evan Longoria, and Carl Crawford, the Rays posted a 95–67 record—a 29-game improvement from their 2007 mark of 66–96—and qualified for the first playoff appearance in the franchise’s history as AL East Division champions. In the American League Championship Series, the Rays bested…
- Garzón Real, Baltasar (Spanish judge)
Baltasar Garzón is a Spanish judge famous for his high-profile investigations into crimes against humanity. Garzón, the second of five children in a middle-class family, grew up in Andalusia in southern Spain. Raised a Roman Catholic, he attended a seminary for several years before abandoning
- Garzón, Baltasar (Spanish judge)
Baltasar Garzón is a Spanish judge famous for his high-profile investigations into crimes against humanity. Garzón, the second of five children in a middle-class family, grew up in Andalusia in southern Spain. Raised a Roman Catholic, he attended a seminary for several years before abandoning
- gas (state of matter)
gas, one of the three fundamental states of matter, with distinctly different properties from the liquid and solid states. The remarkable feature of gases is that they appear to have no structure at all. They have neither a definite size nor shape, whereas ordinary solids have both a definite size
- gas (industrial and domestic)
occupational disease: Gases: Gases may act as local irritants to inflame mucous surfaces. Common examples include sulfur dioxide, chlorine, and fluorine, which have pungent odours and can severely irritate the eyes and the respiratory tract. Some gases, such as nitrogen oxides and phosgene, are much more insidious.…
- gas (fuel)
gasoline, mixture of volatile, flammable liquid hydrocarbons derived from petroleum and used as fuel for internal-combustion engines. It is also used as a solvent for oils and fats. Originally a by-product of the petroleum industry (kerosene being the principal product), gasoline became the
- GAS (psychology)
motivation: Sleep processes and stress reactions: …a stressor is called the general adaptation syndrome and appears to have evolved primarily to deal with systemic stressors. As noted earlier, however, this same set of processes is also triggered by psychological stressors and is often inappropriate to the situation. For example, the stress of an important upcoming test…
- gas balloon (aircraft)
balloon flight: Gas balloons can stay aloft for several days and travel a thousand kilometres or more. Indeed, combination hot-air and gas balloons have crossed continents and oceans and even circled the globe. For scientific research, special gas balloons can float in stable conditions for days or…
- gas bladder (anatomy)
gar: … called a gas bladder or air-breathing organ, which is vascularized to allow for gas exchange with the body. Their jaws and face form a sharp-toothed beak, and their bodies are encased in an armour of diamond-shaped, thick, enameled (ganoid) scales.
- gas buoy (flotation device)
lighthouse: Structure and operation: In earlier times acetylene gas was the only practicable illuminant, which restricted the power of the light. Modern electric buoy lights range in power from a few hundred candelas up to the region of 1,000 candelas, giving ranges of 8 nautical miles (15 km) or so. The lighting equipment…
- gas burner
gas burner, heating device in which natural gas is used for fuel. Gas may be supplied to the burner prior to combustion at a pressure sufficient to induce a supply of air to mix with it; the mixture passes through several long narrow openings or a nozzle to mix with additional air in the combustion
- gas centrifuging (chemistry)
nuclear reactor: Enrichment: In gas centrifuging, the UF6 gas is fed into a high-speed centrifuge. The centrifuge is balanced very well at the top bottom and spins at an extremely high rate. Because of the relative centripetal forces that each atom experiences, the lighter species of this mixture of…
- gas chamber (execution device)
gas chamber, method of executing condemned prisoners by lethal gas. What do you think? Explore the ProCon debate The gas chamber was first adopted in the U.S. state of Nevada in 1921 in an effort to provide a more humane form of capital punishment. On February 8, 1924, Gee Jon became the first
- gas chromatography (chemistry)
gas chromatography, in analytical chemistry, technique for separating chemical substances in which the sample is carried by a moving gas stream through a tube packed with a finely divided solid that may be coated with a film of a liquid. Because of its simplicity, sensitivity, and effectiveness in
- gas cloud (volcanism)
volcano: Gas clouds: Even beyond the limit of explosive destruction, the hot, ash-laden gas clouds associated with an explosive eruption can scorch vegetation and kill animals and people by suffocation. Gas clouds emitted from fumaroles (volcanic gas vents) or from the sudden overturn of a crater…
- gas condensate (chemical compound)
liquefied petroleum gas (LPG), any of several liquid mixtures of the volatile hydrocarbons propene, propane, butene, and butane. It was used as early as 1860 for a portable fuel source, and its production and consumption for both domestic and industrial use have expanded ever since. A typical
- gas constant (chemistry and physics)
universal gas constant, (symbol R), fundamental physical constant arising in the formulation of the ideal gas law. For an ideal gas (approximated by most real gases that are not highly compressed or not near the point of liquefaction), the pressure P times the volume V of the gas divided by its
- gas cycling
petroleum production: Gas cycling: Natural gas reservoirs often contain appreciable quantities of heavier hydrocarbons held in the gaseous state. If reservoir pressure is allowed to decline during gas production, these hydrocarbons will condense in the reservoir to liquefied petroleum gas (LPG) and become unrecoverable. To
- Gas Dynamics Laboratory (Soviet organization)
space exploration: Soviet Union: …was expanded and renamed the Gas Dynamics Laboratory. There in the early 1930s, Valentin Glushko carried out pioneering work on rocket engines. Meanwhile, other rocket enthusiasts in the Soviet Union organized into societies that by 1931 had consolidated into an organization known as GIRD (the abbreviation in Russian for “Group…
- gas electron tube
electron tube, device usually consisting of a sealed glass or metal-ceramic enclosure that is used in electronic circuitry to control a flow of electrons. Among the common applications of vacuum tubes are amplification of a weak current, rectification of an alternating current (AC) to direct
- gas embolism (medical disorder)
air embolism, blockage of an artery or vein by an air bubble. Air can be introduced into the blood vessels during surgery or traumatic accidents. One type of traumatic embolization occurs when lung tissue is ruptured; bubbles of air pass from the alveoli (air sacs) of the lungs into nearby
- gas engine
gasoline engine: Comparison with other engines: The gas engine has much in common with the gasoline engine; in fact, in some instances their differences are very slight at best. Structurally, the difference lies primarily in the substitution of a gas-mixing valve for a carburetor. The cylinder and piston configurations are the same.…
- gas exchange (physiology)
human respiratory system: Gas exchange: Respiratory gases—oxygen and carbon dioxide—move between the air and the blood across the respiratory exchange surfaces in the lungs. The structure of the human lung provides an immense internal surface that facilitates gas exchange between the alveoli and the blood in the pulmonary…
- gas excitation (physics)
colour: Gas excitation: Gas excitation involves the emission of light by a chemical element present as a gas or vapour. When a gas such as neon or a vaporized element such as sodium or mercury is excited electrically, the electrical energy raises the atoms into high…
- gas field
Arctic: Environmental concerns: Oil and gas fields have been particularly bad offenders in this respect. When work on them started—in the 1950s in Siberia and in the 1970s in North America—the reaction of frozen ground to heavy vehicle traffic was not yet widely known, so that many areas of swamp…
- gas gangrene (pathology)
gangrene: …different and more virulent form, gas gangrene, is caused by infection with bacteria of the genus Clostridium, which grow only in the absence of oxygen. It typically develops in deep crushing or penetrating wounds, as in war wounds, that are improperly cleansed; it may also be a sequel to an…
- gas giant (astronomy)
planet: Planets of the solar system: …Jupiter to Neptune are called giant planets or Jovian planets. Between these two main groups is a belt of numerous small bodies called asteroids. After Ceres and other larger asteroids were discovered in the early 19th century, the bodies in this class were also referred to as minor planets or…
- gas grenade (military technology)
grenade: …major class is chemical and gas grenades, which usually burn rather than explode. This class comprises smoke, incendiary (fire-setting), illuminating, chemical-warfare, and tear-gas grenades. The latter are used by police for riot and crowd control. Several uses may be combined, as in a white phosphorous grenade that has smoke, incendiary,…
- gas gun (weapon)
air gun: …shots before replacement is necessary; gas guns are comparable in power and accuracy to air guns.
- Gas Hills (district, Wyoming, United States)
Gas Hills, district rich in uranium deposits, east-southeast of Riverton, central Wyoming, U.S. Uranium was first discovered there by Neil and Maxine McNeice in 1953 on a knoll, now called Discovery Hill, and since then the area has been the object of intense mineral exploration. The uranium-rich
- gas hydrate
natural gas: Dehydration: …in the formation of icelike gas hydrates, which can cause difficulty in plant operation and must be prevented from forming in order to avoid problems in subsequent transportation. Hydrate prevention is accomplished by injecting a glycol solution into the process stream to absorb any dissolved water. The dehydrated gas continues…
- gas hydrate dissociation hypothesis (oceanography and climatology)
methane burp hypothesis, in oceanography and climatology, an explanation of the sudden onset of the Paleocene-Eocene Thermal Maximum (PETM), an interval of geologic time roughly 55 million years ago characterized by the highest global temperatures of the Cenozoic Era (65 million years ago to the
- gas laser (physics)
laser: History: …Bell Labs built the first gas laser, which generated a continuous infrared beam from a mixture of helium and neon. In 1962 Robert N. Hall and coworkers at the General Electric Research and Development Center in Schenectady, New York, made the first semiconductor laser.
- gas law, second (physics)
Charles’s law, a statement that the volume occupied by a fixed amount of gas is directly proportional to its absolute temperature, if the pressure remains constant. This empirical relation was first suggested by the French physicist J.-A.-C. Charles about 1787 and was later placed on a sound
- gas laws (physics)
gas laws, laws that relate the pressure, volume, and temperature of a gas. Boyle’s law—named for Robert Boyle—states that, at constant temperature, the pressure P of a gas varies inversely with its volume V, or PV = k, where k is a constant. Charles’s law—named for J.-A.-C. Charles
- gas lift
petroleum production: Primary recovery: natural drive and artificial lift: Another method, called gas lift, uses gas bubbles to lower the density of the oil, allowing the reservoir pressure to push it to the surface. Usually, the gas is injected down the annulus between the casing and the production tubing and through a special valve at the bottom…
- gas lift pump
pump: Electromagnetic pumps.: Gas lifts are used to raise liquids from the bottoms of wells. Compressed gas is introduced into the liquid near the bottom of the well as in Figure 6. The resulting mixture of gas and liquid is lighter and more buoyant than the liquid alone…
- Gas Light (play by Hamilton)
gaslighting: …a 1938 British stage play, Gas Light, which was subsequently produced as a film, Gaslight, in the United Kingdom (1940) and the United States (1944). Those dramas vividly, if somewhat simplistically, depicted some of the basic elements of the technique. These may include: attempting to convince the victims of the…
- gas light (technology)
stagecraft: Early history: …centuries was the introduction of gas lighting. Near the end of the 18th century, the Scottish engineer William Murdock developed a practical method to distill gas from coal for illumination. The first successful adaptation of gas lighting for the stage was demonstrated in the Lyceum Theatre, London, in 1803 by…
- Gas Light and Coke Company (British company)
construction: Improvements in building services: The Gas Light and Coke Company was founded in London in 1812 as the first real public utility, producing coal gas as a part of the coking process in large central plants and distributing it through underground pipes to individual users; soon many major cities had…
- gas mantle
incandescent lamp: Nonelectric incandescent lamps: Nonelectric incandescent lamps include the gas-mantle lamp. The mantle is a mesh bag of fabric impregnated with a solution of nitrates of cerium and one or more of the following metals: thorium, beryllium, aluminum, or magnesium. The mantle is fixed over an orifice carrying a flammable gas such as natural…
- gas maser (device)
maser: Gas masers: Generation of radio waves by stimulated emission of radiation has been achieved in several gases in addition to ammonia. Hydrogen cyanide molecules have been used to produce a wavelength of 3.34 mm. Like the ammonia maser, this maser uses electric fields to select…
- gas mask (protective device)
gas mask, breathing device designed to protect the wearer against harmful substances in the air. The typical gas mask consists of a tight-fitting facepiece that contains filters, an exhalation valve, and transparent eyepieces. It is held to the face by straps and can be worn in association with a
- gas meter (measurement device)
gas meter, device for measuring the quantity or rate of flow of a gas. Types of gas meters (by operating principles) include displacement, velocity, head, thermal, acoustic, and tracer. An example of the displacement principle is the bellows-and-diaphragm gas meter (shown in the diagram). This type
- gas multiplication (physics)
ionization chamber: This effect, called gas multiplication, makes the output electric pulse proportional to the ionization produced by the radiation entering the counter and thus permits differentiation among particles of various kinds and energies.
- gas operation (weapon)
machine gun: …of these two methods is gas operation. In this method, the energy required to operate the gun is obtained from the pressure of gas tapped off from the barrel after each cartridge explodes. In a typical gas-operated machine gun, an opening or port is provided in the side of the…
- gas plant (plant species)
gas plant, (Dictamnus albus), gland-covered herb of the rue family (Rutaceae). Gas plant is native to Eurasia and is grown as an ornamental in many places. The flowers (white or pink) and the leaves give off a strong aromatic vapour that can be ignited—hence the names gas plant and burning bush.
- gas reservoir (geology)
gas reservoir, in geology and natural gas production, a naturally occurring storage area, characteristically a folded rock formation such as an anticline, that traps and holds natural gas. The reservoir rock must be permeable and porous to contain the gas, and it has to be capped by impervious rock
- gas sensor (instrument)
conductive ceramics: Gas sensors: In addition to the heating electrode applications noted above, tin oxide also is used in carbon monoxide gas sensors for home and industry. Adsorption of carbon monoxide at contacts between particles of SnO2 produces local charge states that alter the…
- gas shell (military technology)
artillery: Projectile, powder, and fuze: …illuminated the battlefield at night; gas shells, filled with various chemicals such as chlorine or mustard gas, were used against troops; incendiary shells were developed for setting fire to hydrogen-filled zeppelins. High explosives were improved, with TNT (trinitrotoluene) and amatol (a mixture of TNT and ammonium nitrate) becoming standard shell…
- gas sphere (physics)
Robert Emden: …of expansion and compression of gas spheres and applied it to stellar structure.
- gas station (business)
operations research: Model construction: …the cars stopping at urban automotive service stations located at intersections of two streets revealed that almost all came from four of the 16 possible routes through the intersection (four ways of entering times four ways of leaving). Examination of the percentage of cars in each route that stopped for…
- gas thermometer (measurement instrument)
thermometer: Gas thermometers work best at very low temperatures. Liquid thermometers were once the most common type in use. They were simple, inexpensive, long-lasting, and able to measure a wide temperature span. The liquid was almost always mercury or coloured alcohol, sealed in a glass tube…
- gas transport (physiology)
human respiratory system: Gas exchange: Respiratory gases move between the environment and the respiring tissues by two principal mechanisms, convection and diffusion. Convection, or mass flow, is responsible for movement of air from the environment into the lungs and for movement of blood between the lungs and the
- gas vacuole (biology)
bacteria: Cytoplasmic structures: Many aquatic bacteria produce gas vacuoles, which are protein-bound structures that contain air and allow the bacteria to adjust their buoyancy. Bacteria can also have internal membranous structures that form as outgrowths of the cytoplasmic membrane.
- gas warfare
World War I: The Western Front, 1915: …April 22, 1915, they used chlorine gas for the first time on the Western Front, but they made the mistake of discharging it from cylinders (which were dependent on a favourable wind) rather than lobbing it onto the enemy trenches in artillery shells. The gas did throw the agonized defenders…
- gas welding (industry)
welding: Thermochemical processes: One such process is gas welding. It once ranked as equal in importance to the metal-arc welding processes but is now confined to a specialized area of sheet fabrication and is probably used as much by artists as in industry. Gas welding is a fusion process with heat supplied…
- gas, intestinal (biology)
intestinal gas, material contained within the digestive tract that consists principally of swallowed air and partly of by-products of digestion. In humans the digestive tract contains normally between 150 and 500 cubic cm (10 and 30 cubic inches) of gas. During eating, air is swallowed into the
- gas, natural
natural gas, colourless highly flammable gaseous hydrocarbon consisting primarily of methane and ethane. It is a type of petroleum that commonly occurs in association with crude oil. A natural resource and fossil fuel, natural gas is used for electricity generation, heating, and cooking and as a
- gas-cooled fast-breeder reactor (physics)
nuclear reactor: Coolant system: In most light-water, heavy-water, and gas-cooled power reactors, the coolant is maintained at high pressure. Sodium and organic coolants operate at atmospheric pressure.
- gas-diffusion electrode
fuel cell: Development of fuel cells: …resulted in the invention of gas-diffusion electrodes in which the fuel gas on one side is effectively kept in controlled contact with an aqueous electrolyte on the other side. By mid-century O.K. Davtyan of the Soviet Union had published the results of experimental work on solid electrolytes for high-temperature fuel…
- gas-discharge lamp (instrument)
electric discharge lamp, lighting device consisting of a transparent container within which a gas is energized by an applied voltage and thereby made to glow. The French astronomer Jean Picard observed (1675) a faint glow in the tube of a mercury barometer when it was agitated, but the cause of the
- gas-driven transducer (instrument)
ultrasonics: Transducers: Mechanical devices include gas-driven, or pneumatic, transducers such as whistles as well as liquid-driven transducers such as hydrodynamic oscillators and vibrating blades. These devices, limited to low ultrasonic frequencies, have a number of industrial applications, including drying, ultrasonic cleaning, and injection of fuel oil into burners. Electromechanical transducers…
- gas-filled converter (device)
thermionic power converter: Gas-filled or plasma converters: These devices are designed so that positively charged ions are continuously generated and mixed with negatively charged electrons in the space between the emitter and the collector to provide a plasma with a relatively neutral space charge. Because of this, a…
- gas-filled detector (radiation detection)
radiation measurement: Gas-filled detectors: The passage of a charged particle through a gas results in the transfer of energy from the particle to electrons that are part of the normal atomic structure of the gas. If the charged particle passes close enough to a given atom, the…
- gas-filled tube
electron tube, device usually consisting of a sealed glass or metal-ceramic enclosure that is used in electronic circuitry to control a flow of electrons. Among the common applications of vacuum tubes are amplification of a weak current, rectification of an alternating current (AC) to direct
- gas-liquid chromatography (chemistry)
chromatography: Gas chromatography: …subdivided into gas-solid chromatography and gas-liquid chromatography. The carrier gases used, such as helium, hydrogen, and nitrogen, have very weak intermolecular interactions with solutes. Molecular sieves are used in gas size-exclusion chromatography applied to gases of low molecular weight. Adsorption on solids tends to give nonlinear systems. Gas-liquid chromatography employs…
- gas-mantle lamp
incandescent lamp: Nonelectric incandescent lamps: Nonelectric incandescent lamps include the gas-mantle lamp. The mantle is a mesh bag of fabric impregnated with a solution of nitrates of cerium and one or more of the following metals: thorium, beryllium, aluminum, or magnesium. The mantle is fixed over an orifice carrying a flammable gas such as natural…
- gas-phase polymerization (chemistry)
chemistry of industrial polymers: Gas-phase polymerization: This method is used with gaseous monomers such as ethylene, tetrafluoroethylene, and vinyl chloride. The monomer is introduced under pressure into a reaction vessel containing a polymerization initiator. Once polymerization begins, monomer molecules diffuse to the growing polymer chains. The resulting polymer is…
- gas-sensing electrode
fuel cell: Development of fuel cells: …resulted in the invention of gas-diffusion electrodes in which the fuel gas on one side is effectively kept in controlled contact with an aqueous electrolyte on the other side. By mid-century O.K. Davtyan of the Soviet Union had published the results of experimental work on solid electrolytes for high-temperature fuel…
- gas-solid chromatography (chemistry)
separation and purification: Chromatography: In addition to chromatography, gas-solid distribution is also widely employed for purification, using special adsorbents called molecular sieves. These materials contain pores of approximately the same dimensions as small molecules. This property can be exploited in the separation of molecules having linear structures from those having bulky structures. The…
- gas-turbine engine
gas-turbine engine, any internal-combustion engine employing a gas as the working fluid used to turn a turbine. The term also is conventionally used to describe a complete internal-combustion engine consisting of at least a compressor, a combustion chamber, and a turbine. Useful work or propulsive
- gasal (Islamic literature)
ghazal, in Islamic literatures, genre of lyric poem, generally short and graceful in form and typically dealing with themes of love. As a genre the ghazal developed in Arabia in the late 7th century from the nasib, which itself was the often amorous prelude to the qaṣīdah (ode). Two main types of
- Gascogne (historical region, France)
Gascony, historical and cultural region encompassing the southwestern French départements of Landes, Gers, and Hautes-Pyrénées and parts of Pyrénées-Atlantiques, Lot-et-Garonne, Tarn-et-Garonne, Haute-Garonne, and Ariège and coextensive with the historical region of Gascony. During ancient Roman
- Gascogne, Golfe de (bay, Europe)
Bay of Biscay, wide inlet of the North Atlantic Ocean indenting the coast of western Europe. Forming a roughly triangular body with an area of about 86,000 square miles (223,000 square km), it is bounded on the east by the west coast of France and on the south by the north coast of Spain. Its
- Gascoigne, George (English poet)
George Gascoigne was an English poet and a major literary innovator. Gascoigne attended the University of Cambridge, studied law at Gray’s Inn in 1555, and thereafter pursued careers as a politician, country gentleman, courtier, soldier of fortune, and man of letters, all with moderate distinction.
- Gascon (people)
France: The shrinking of the frontiers and peripheral areas: To the southwest the Gascons, a highland people from the Pyrenees, had been driven northward by the Visigoths in 578 and settled in Novempopulana; in spite of several Frankish expeditions, this area was not subdued. In the south the Franks were unable to gain control of Septimania; they tried…