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  • alienation effect (theatre)
    idea central to the dramatic theory of the German dramatist-director Bertolt Brecht. It involves the use of techniques designed to distance the audience from emotional involvement in the play through jolting reminders of the artificiality of the theatrical performance....
  • Aliénor d’Aquitaine (queen consort of France and England)
    queen consort of both Louis VII of France (1137–52) and Henry II of England (1152–1204) and mother of Richard I (the Lion-Heart) and John of England. She was perhaps the most powerful woman in 12th-century Europe....
  • Aliénor de Guyenne (queen consort of France and England)
    queen consort of both Louis VII of France (1137–52) and Henry II of England (1152–1204) and mother of Richard I (the Lion-Heart) and John of England. She was perhaps the most powerful woman in 12th-century Europe....
  • Aliens Act (Great Britain [1705])
    ...(see Act of Union). Here again, Godolphin was the dominant figure, calling the Scottish Parliament’s bluff when it announced it would not accept the Hanoverian succession. Godolphin passed the Aliens Act (1705), which would have prohibited all trade between England and Scotland—no mere scare tactic in light of the commercial policy that was crippling the Irish economy. Rath...
  • aliettite (mineral)
    ...rectorite (dioctahedral mica/montmorillonite), tosudite (dioctahedral chlorite/smectite), corrensite (trioctahedral vermiculite/chlorite), hydrobiotite (trioctahedral mica/vermiculite), aliettite (talc/saponite), and kulkeite (talc/chlorite). Other than the ABAB . . . type with equal numbers of the two component layers in a structure, many modes of......
  • Aliev, Geidar (president of Azerbaijan)
    Azerbaijani politician (b. May 10, 1923, Nakhichevan region, Transcaucasian S.F.S.R., U.S.S.R. [now an autonomous region of Azerbaijan]—d. Dec. 12, 2003, Cleveland, Ohio), was one of the most powerful men in Azerbaijan for more than 30 years, as deputy chairman (1964–67) and chairman (1967–69) of the regional KGB, as secretary (1969–87) of the Communist Party of Azerbai...
  • Aligarh (India)
    city, west-central Uttar Pradesh state, northern India. It lies southeast of Delhi. The city itself is usually called Koil, or Kol; Alīgarh is the name of a nearby fort. The city is an agricultural trade centre; the processing of agricultural products and manufacturing are also important. Alīgarh Muslim University (1875) and its affiliated colleg...
  • Aligarh Muslim University (university, Aligarh, India)
    Muslim educator, jurist, and author, founder of the Anglo-Mohammedan Oriental College at Alīgarh, Uttar Pradesh, India, and the principal motivating force behind the revival of Indian Islām in the late 19th century. His works, in Urdu, include Essays on the Life of Mohammed (1870) and commentaries on the Bible and on the Qurʾān. In 1888 he was made a Knight......
  • Aliger, Margarita Iosifovna (Russian writer, and Soviet propagandist)
    Russian poet, journalist, and Soviet propagandist....
  • Alighieri, Dante (Italian poet)
    Italian poet, prose writer, literary theorist, moral philosopher, and political thinker. He is best known for the monumental epic poem La commedia, later named La divina commedia (The Divine Comedy)....
  • alignment (megalith)
    monument consisting of multiple rows of large upright stones, primarily located in Brittany and built during Neolithic and Early Bronze times. See megalith....
  • alignment (engineering)
    After a route has been selected, a three-dimensional road alignment and its associated cross-sectional profiles are produced. In order to reduce the amount of earth to be moved, the alignment is adjusted where practical so that the earth to be excavated is in balance with the embankments to be built. Computers allow many options to be explored and realistic views of the future road to be......
  • alignment chart (mathematics)
    calculating chart with scales that contain values of three or more mathematical variables, widely used in engineering, industry, and the natural and physical sciences....
  • alii (Polynesian nobility)
    ...(gods), provided that they themselves possess it. Derived from a root term that has aristocratic connotations, mana corresponds to Polynesian social classifications. The ariki, or alii, the nobility of Polynesia, have more mana than commoners, and both their land and the insignia associated with them have mana. Besides areas and symbolic......
  • ʿalim (Islam)
    the learned of Islam, those who possess the quality of ʿilm, “learning,” in its widest sense. From the ʿulamāʾ, who are versed theoretically and practically in the Muslim sciences, come the religious teachers of the Islamic community—theologians (mutakallimun), canon lawyers (muftis), judges (qadis), professors—and high state re...
  • alimenta (ancient Rome)
    ...An agrarian reform measure and the last lex populi in Roman history were implemented in Italy. The one imaginative innovation commonly attributed to Nerva’s government, the system of alimenta, or trusts for the maintenance of poor children in Italy, may have been the work of Trajan. In order to secure the succession, Nerva in 97 adopted and took as his colleague Marcus Ulpi...
  • alimentary canal
    pathway by which food enters the body and solid wastes are expelled. The alimentary canal includes the mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus. See digestion....
  • alimentary paste (food)
    a shaped and dried dough prepared from semolina, farina, wheat flour, or a mixture of these with water or milk and with or without egg or egg yolk. See pasta....
  • alimentary system (anatomy)
    ...
  • alimentary tract
    pathway by which food enters the body and solid wastes are expelled. The alimentary canal includes the mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus. See digestion....
  • alimony (law)
    in divorce law, compensation owed by one spouse to the other for financial support after divorce. Alimony aims at support of the one spouse, not punishment of the other. In some places, the term means simply a property settlement irrespective of future support. Alimony has traditionally been granted from husbands to wives but has occasionally been granted from wives to husbands....
  • Alinagar, Treaty of (Great Britain-India [1757])
    (Feb. 9, 1757), pact concluded in India by the British agent Robert Clive after his recovery of Calcutta on Jan. 2, 1757, from the nawab of Bengal, Sirāj-ud-Dawlah. The treaty was the prelude to the British seizure of Bengal. The Nawab had seized Calcutta in June 1756, but he was eager to secure his rear from the th...
  • Aline, reine de Golconde (work by Boufflers)
    French writer, soldier, and academician remembered chiefly for his picaresque romance, Aline, reine de Golconde (“Aline, Queen of Golconde”)....
  • Alīngār (river, Asia)
    ...on the southern one, where valleys follow two contrasting directions—northeast to southwest and roughly east to west. Most of the rivers, such as the Panjshēr (Panjshīr), the Alīngār, the Konar, and the Panjkora, follow the northeast-to-southwest direction and are then suddenly deflected toward the east-west axis by the Kābul River, into which they flow...
  • Alinsky, Saul David (American activist)
    American social organizer who stimulated the creation of numerous activist citizen and community groups....
  • aliphatic compound (chemical compound)
    any chemical compound belonging to the organic class in which the atoms are not linked together to form a ring. One of the major structural groups of organic molecules, the aliphatic compounds include the alkanes, alkenes, and alkynes, and substances derived from them—actually or in principle—by replacing one or more hydrogen atoms by atoms of other elements or groups of atoms. ...
  • Alipore (India)
    town, West Bengal state, northeastern India. A southern suburb of Calcutta included within the city municipality, it has major industries, including printing and bookbinding, cement manufacture, oilseed milling, and general engineering works. Alīpore is the site of zoological-horticultural gardens and of Belvedere House, onetime residence of the former British lieutenant governor of Bengal ...
  • Alipur (India)
    town, West Bengal state, northeastern India. A southern suburb of Calcutta included within the city municipality, it has major industries, including printing and bookbinding, cement manufacture, oilseed milling, and general engineering works. Alīpore is the site of zoological-horticultural gardens and of Belvedere House, onetime residence of the former British lieutenant governor of Bengal ...
  • Alipur Duar (India)
    city, northeastern West Bengal state, northeastern India, just north of the Kalyāni River. Connected by road with Jalpaiguri, the city is an important market centre for rice, tobacco, and jute; an annual agricultural produce and stock fair is held there. Rice milling is an important industry. Alīpur Duār was declared a municipality in 1951...
  • Aliquippa (Pennsylvania, United States)
    city, Beaver county, western Pennsylvania, U.S. It lies along the Ohio River, just northwest of Pittsburgh. Settled about 1750 as a post for trade with Delaware, Iroquois, and Shawnee Indians, it was first known as Logstown and later renamed for “Queen” Aliquippa, probabl...
  • Alişar Hüyük (archaeological site, Turkey)
    site of an ancient Anatolian town southeast of Boğazköy in central Turkey. Thorough and extensive excavations there by the Oriental Institute of the University of Chicago (1927–32) were the first systematic stratigraphic investigations on the Anatolian plateau. In the long succession of strata revealed at Alişar Hüyük—from Chalcolithic (c. 4...
  • Alishoni lingenandaba (work by Bongela)
    ...in stark polarities. Qangule’s Izagweba (1972; “Weapons”) depicts the conflict between uncompromising traditionalists and Westernized, urbanized individuals. Bongela’s Alishoni lingenandaba (1971; “The Sun Does Not Set Without News”) deals with the squalor and corruption of life in the black townships surrounding the affluent w...
  • Alisjahbana, Takdir (Indonesian writer)
    ...literature in Dutch, and the nationalist leaders had become eager for a new literature in the native language. This common aim bore fruit in 1933, when a literary journal under the editorship of Takdir Alisjahbana appeared, containing poems and essays written by various authors in the new Malay, which they now called Indonesian. The editor himself later wrote in Indonesian a number of......
  • Alisma (plant)
    any freshwater perennial herb of the genus Alisma, commonly found in lakes, ponds, and ditches. The three or four species are widely distributed throughout the North Temperate Zone and Australia. Water-plantain leaves float or extend out of the water. They are sometimes ribbonlike or grasslike, are without lobes, and are often heart-shaped or tapered at the base. Flowers have three green s...
  • Alisma plantago-aquatica (plant)
    A. triviale, regarded by some authorities as a New World variety of the European species A. plantago-aquatica, is common throughout North America. The plant grows to about 1 m (40 inches) in height and has ovate, slightly pointed leaves. The flowers are about 6 mm (0.25 inch) long and grow in whorls along a many-branched stalk. A. subcordatum has smaller flowers that are......
  • Alisma subcordatum (plant)
    ...North America. The plant grows to about 1 m (40 inches) in height and has ovate, slightly pointed leaves. The flowers are about 6 mm (0.25 inch) long and grow in whorls along a many-branched stalk. A. subcordatum has smaller flowers that are about 2 mm long. ...
  • Alisma triviale (plant)
    A. triviale, regarded by some authorities as a New World variety of the European species A. plantago-aquatica, is common throughout North America. The plant grows to about 1 m (40 inches) in height and has ovate, slightly pointed leaves. The flowers are about 6 mm (0.25 inch) long and grow in whorls along a many-branched stalk. A.......
  • Alismales (plant order)
    arrowhead and pondweed order of flowering plants, belonging to the monocotyledon (monocot) group, whose species have a single seed leaf. Most of the some 4,500 species are aquatic and grow submersed or partially exposed to the air in marshes and other freshwater and marine habitats, where they are treated as weeds...
  • Alismataceae (plant family)
    The family Alismataceae occurs throughout the Americas, Asia, Australia, Africa, and Europe. Common genera include Sagittaria (arrowhead), Alisma (water plantain), and Echinodorus (burhead). Water plantain and arrowhead are most common in temperate regions, whereas burhead has its centre of distribution in the......
  • Alismatales (plant order)
    arrowhead and pondweed order of flowering plants, belonging to the monocotyledon (monocot) group, whose species have a single seed leaf. Most of the some 4,500 species are aquatic and grow submersed or partially exposed to the air in marshes and other freshwater and marine habitats, where they are treated as weeds...
  • Alisol (FAO soil group)
    one of the 30 soil groups in the classification system of the Food and Agriculture Organization (FAO). Alisols are highly acidic, poorly drained soils prone to aluminum toxicity and water erosion. Liming and fertilization are essential to their agricultural use—primarily for growing oil palm, corn (maize), and cotton. Their extent has not been establish...
  • Alison, Archibald (British philosopher)
    ...William Wordsworth in England. For such writers, imagination was to be the distinctive feature both of aesthetic activity and of all true insight into the human condition. Meanwhile, Lord Kames and Archibald Alison had each provided full accounts of the role of association in the formation and justification of critical judgment. Alison, in particular, recognized the inadequacies of the......
  • Alison’s House (play by Glaspell)
    ...entitled The Road to the Temple. Subsequently she published The Comic Artist (1927), a play on which she collaborated with Norman H. Matson (to whom she was married for a time), and Alison’s House (1930), a play that was awarded the Pulitzer Prize. Her later novels included The Fugitive’s Return (1929) and The Morning Is Near Us (1939)....
  • Alitalia-Linee Aeree Italiane (Italian airline)
    Italian international airline founded in 1946 and, by the early 21st century, serving more than 80 cities in Europe, Africa, Asia, North and South America, and Australia. Headquarters are in Rome. The pope usually flies on a chartered Alitalia jet nicknamed “Shepherd One.”...
  • Alito, Samuel A., Jr. (United States jurist)
    associate justice of the Supreme Court of the United States from 2006....
  • Alito, Samuel Anthony, Jr. (United States jurist)
    associate justice of the Supreme Court of the United States from 2006....
  • Alitus (Lithuania)
    city, southern Lithuania. It lies along the Neman (Lithuanian: Nemunas) River, 37 miles (60 km) south of Kaunas. The city dates from the 14th century. In the 20th century it developed as an industrial centre, with factories producing refrigerators, chemical products, linen, and clothing. Alytus is a rail terminus and road junction and has an agricultural college. Pop. (1994 est.) 77,400....
  • Aliutor language
    ...and northward to the Anadyr River basin, (3) the strongly divergent but probably related Itelmen (or Kamchadal), with a bare remnant of 500 speakers on the central west coast of Kamchatka, (4) Aliutor, perhaps a Koryak dialect, with about 2,000 speakers, and (5) Kerek, with about 10 speakers....
  • alivincular ligament (mollusk anatomy)
    ...an elastic ligament creates the opening thrust that operates against the closing action of the adductor muscles. The ligament typically develops either externally (parivincular) or internally (alivincular) but comprises outer lamellar, and inner fibrous, layers secreted by the mantle crest. The ligament type is generally characteristic of each bivalve group. The hinge plate with ligament......
  • Alix of Brittany (wife of Peter I)
    Married by his cousin King Philip II Augustus of France to Alix, heiress to Brittany, Peter did homage for the province in 1213 and assumed the title of duke, though he was considered merely a count by the French. He energetically asserted his authority over the Breton lands, annexing new fiefs to the ducal domain, granting privileges to the towns, and regularizing the administration....
  • Alix, Princess von Hesse-Darmstadt (empress consort of Russia)
    consort of the Russian emperor Nicholas II. Her misrule while the emperor was commanding the Russian forces during World War I precipitated the collapse of the imperial government in March 1917....
  • aliyah (Judaism)
    in Judaism, the honour accorded to a worshiper of being called up to read an assigned passage from the Torah (first five books of the Bible). Because the passage assigned for each sabbath-morning service is subdivided into a minimum of seven sections, at least seven different persons are called up for these readings. An additional reader is called up to repeat part of the final ...
  • Aliyev, Abulfaz Kadyrgula ogly (president of Azerbaijan)
    Azerbaijani historian and nationalist leader (b. June 7, 1938, Keleki, Nakhichevan A.S.S.R, U.S.S.R.—d. Aug. 22, 2000, Ankara, Turkey), was a leading anti-Soviet dissident and cofounder (1989) of the nationalist Azerbaijan Popular Front, before becoming the first democratically elected president of newly independent Azerbaijan in June 1992. He proved to be an ineffectual president, however,...
  • Aliyev, Heydar (president of Azerbaijan)
    Azerbaijani politician (b. May 10, 1923, Nakhichevan region, Transcaucasian S.F.S.R., U.S.S.R. [now an autonomous region of Azerbaijan]—d. Dec. 12, 2003, Cleveland, Ohio), was one of the most powerful men in Azerbaijan for more than 30 years, as deputy chairman (1964–67) and chairman (1967–69) of the regional KGB, as secretary (1969–87) of the Communist Party of Azerbai...
  • Aliyev, Ilham (president of Azerbaijan)
    ...in Azerbaijan began to soar, as new fields were discovered and new contracts were signed with Western companies for their exploitation. In 2003 the elderly Aliyev died and was succeeded by his son, Ilham, whom Aliyev had been grooming for succession. Scandalized by the apparent accession to power of a hereditary line, opposition political groups staged a series of violent protests that failed.....
  • aliyot (Judaism)
    in Judaism, the honour accorded to a worshiper of being called up to read an assigned passage from the Torah (first five books of the Bible). Because the passage assigned for each sabbath-morning service is subdivided into a minimum of seven sections, at least seven different persons are called up for these readings. An additional reader is called up to repeat part of the final ...
  • aliyoth (Judaism)
    in Judaism, the honour accorded to a worshiper of being called up to read an assigned passage from the Torah (first five books of the Bible). Because the passage assigned for each sabbath-morning service is subdivided into a minimum of seven sections, at least seven different persons are called up for these readings. An additional reader is called up to repeat part of the final ...
  • ʿaliyya (Judaism)
    in Judaism, the honour accorded to a worshiper of being called up to read an assigned passage from the Torah (first five books of the Bible). Because the passage assigned for each sabbath-morning service is subdivided into a minimum of seven sections, at least seven different persons are called up for these readings. An additional reader is called up to repeat part of the final ...
  • ʿaliyyot (Judaism)
    in Judaism, the honour accorded to a worshiper of being called up to read an assigned passage from the Torah (first five books of the Bible). Because the passage assigned for each sabbath-morning service is subdivided into a minimum of seven sections, at least seven different persons are called up for these readings. An additional reader is called up to repeat part of the final ...
  • alizarin (pigment)
    a red dye originally obtained from the root of the common madder plant, Rubia tinctorum, in which it occurs combined with the sugars xylose and glucose. The cultivation of madder and the use of its ground root for dyeing by the complicated Turkey red process were known in ancient India, Persia, and Egypt; the use spread to Asia Minor about the 10th century and was introdu...
  • alizarine (pigment)
    a red dye originally obtained from the root of the common madder plant, Rubia tinctorum, in which it occurs combined with the sugars xylose and glucose. The cultivation of madder and the use of its ground root for dyeing by the complicated Turkey red process were known in ancient India, Persia, and Egypt; the use spread to Asia Minor about the 10th century and was introdu...
  • alize (wind)
    ...there are two distinct seasons, dry and wet. The dry season, which lasts from November to June, is marked by low humidity and high temperatures and is influenced by the alize and harmattan winds. The alize blows from the northeast from November to January and causes a relatively cool spell, with temperatures......
  • aljamiado literature
    ...of Castile, had abandoned Arabic for the Castilian spoken by their Christian neighbours. They continued to write in Arabic, however, giving rise to their characteristic aljamiado literature....
  • Aljechin, Alexander (Russian-French chess player)
    world champion chess player from 1927 to 1935 and from 1937 until his death, noted for using a great variety of attacks....
  • Aljubarrota, Battle of (Portugal [1385])
    ...west-central Portugal, just south of Leiria city. The town is dominated by the great Dominican abbey of Santa Maria da Vitória, also known simply as Batalha (“Battle”). In the Battle of Aljubarrota, fought on a plain 9 miles (14 km) southwest of the town, John I of Portugal defeated John I of Castile in 1385 and secured the independence of his kingdom. The abbey was......
  • alka (Baltic religion)
    in Baltic religion, an open-air religious site, a natural sanctuary—forest, hill, river—that was sacred and inviolate. Trees could not be cut in such forests, sacred fields could not be plowed, and fishing was not allowed in the holy waters. The rituals of various religious cults, involving animal sacrifice and human cremation, took place at the alkas. The sense of the ancient...
  • alkadiene (chemical compound)
    Compounds that contain two double bonds are classified as dienes, those with three as trienes, and so forth. Dienes are named by replacing the -ane suffix of the corresponding alkane by -adiene and identifying the positions of the double bonds by numerical locants. Dienes are classified as cumulated, conjugated, or isolated according to whether the double bonds constitute a......
  • Alkalai, Judah ben Solomon Hai (Sephardic rabbi)
    Sephardic rabbi and an early advocate of Jewish colonization of Palestine....
  • alkalemia (pathology)
    abnormally low level of acidity, or high level of alkalinity, in the body fluids, including the blood. Alkalosis may be either metabolic or respiratory in origin. Metabolic alkalosis results from either acid loss (which may be caused by severe vomiting or by the use of potent diuretics [substances that promote production of urine]) or bicarbonate gain (which may be caused by excessive intake of......
  • alkali (chemical compound)
    any of the soluble hydroxides of the alkali metals—i.e., lithium, sodium, potassium, rubidium, and cesium. Alkalies are strong bases that turn litmus paper from red to blue; they react with acids to yield neutral salts; and they are caustic and in concentrated form are corrosive to organic tissues. The term alkali is also applied to the soluble hydroxides of such alkaline-earth meta...
  • Alkali (missile)
    The Soviets fielded an extended series of air-to-air missiles, beginning in the 1960s with the AA-1 Alkali, a relatively primitive semiactive radar missile, the AA-2 Atoll, an infrared missile closely modeled after the Sidewinder, and the AA-3 Anab, a long-range, semiactive radar-homing missile carried by air-defense fighters. The AA-5 Ash was a large, medium-range radar-guided missile, while......
  • Alkali Act (United Kingdom [1862])
    ...and other chemical industries were also attracted to the growing town. Enormous quantities of toxic and evil-smelling waste from the alkali industry produced ugly refuse dumps, but the first Alkali Act of 1862 was the beginning of the slow introduction of stricter operating conditions. Widnes town centre developed in the second half of the 19th century around Victoria Square....
  • alkali basalt (rock)
    Normal alkali basalt contains olivine and, commonly, a diopsidic or titaniferous augite. Alkali basalts predominate among the lavas of the ocean basins and are common among the mafic lavas of the forelands and backlands of the mountain belts. In the Brito-Icelandic province the Tertiary lava flows of the Inner Hebrides, Antrim, and the Faroe Islands include great successions of both calc-alkali......
  • alkali bee (insect)
    Examples of flowers that depend heavily on bees are larkspur, monkshood, bleeding heart, and Scotch broom. Alkali bees (Nomia) and leaf-cutter bees (Megachile) are both efficient pollinators of alfalfa; unlike honeybees, they are not afraid to trigger the explosive mechanism that liberates a cloud of pollen in alfalfa flowers. Certain Ecuadorian orchids (Oncidium) are......
  • alkali feldspar (mineral)
    any of several common silicate minerals that often occur as variously coloured, glassy crystals. They are used in the manufacture of glass and ceramics; transparent, highly coloured, or iridescent varieties are sometimes used as gemstones. The alkali feldspars are primarily important as constituents of rocks; they are very widespread and abundant in alkali and acidic igneous rocks (particularly sy...
  • alkali flat (geological feature)
    a playa, or dried-out desert lake, especially one containing high concentrations of precipitated dry, glistening salts. The term is generally limited to flats in the western United States, the most famous being the Bonneville Salt Flats west of Salt Lake City, where automobile speed records are set....
  • Alkali Flat (geological feature, New Mexico, United States)
    ...crystals created by the evaporation of gypsum-laden runoff water. The gypsum is the product of decomposed limestone, which is the predominant rock type of the surrounding region. The extensive Alkali Flat area, to the north of the lake, is similarly created by underground water drawn to the surface. There is little plant life; the animals, mainly mice and lizards, are light-hued, blending......
  • alkali halide (chemical compound)
    ...each ion has as many neighbours as possible, consistent with the ion radii. Six or eight nearest neighbours are typical; the number depends on the size of the ions and not on the bond angles. The alkali halide crystals are binaries of the AH type, where A is an alkali ion (lithium [Li], sodium, potassium, rubidium, or cesium) and H is a halide ion (fluorine, chlorine,......
  • alkali iodide (chemical compound)
    The alkali iodides are soluble in molten iodine and give conducting solutions typical of weak electrolytes. Alkali iodides react with compounds containing iodine with the oxidation number +1, such as iodine bromide, as in the following equation:...
  • alkali lake
    Lakes that contain high concentrations of sodium sulfate are called bitter lakes, and those containing sodium carbonate are called alkali lakes. Soda Lake, California, is estimated to contain nearly 1,000,000 tons of anhydrous sulfate. Magnesium salts of these types are also quite common and can be found in the same sediments as the sodium salts. Other salts of importance occurring in lake......
  • alkali land (geological feature)
    a playa, or dried-out desert lake, especially one containing high concentrations of precipitated dry, glistening salts. The term is generally limited to flats in the western United States, the most famous being the Bonneville Salt Flats west of Salt Lake City, where automobile speed records are set....
  • alkali metal (chemical element)
    any of the six chemical elements that make up Group 1 (Ia) of the periodic table—namely, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). The alkali metals are so called because reaction with ...
  • alkali refining
    Many of these can be removed by treating fats at 40° to 85° C (104° to 185° F) with an aqueous solution of caustic soda (sodium hydroxide) or soda ash (sodium carbonate). The refining may be done in a tank (in which case it is called batch or tank refining) or in a continuous system. In batch refining, the aqueous emulsion of soaps formed from free fatty acids, along wi...
  • alkali-heath family (plant family)
    ...Central Asia but scarce in other ecosystems. The cactus family is very prominent in deserts in the Americas but absent elsewhere. Another example is the smaller and generally less well-known family Frankeniaceae, which is typical of salty habitats and reaches its greatest diversity in deserts from North Africa to Central Asia and in western South America....
  • alkali-lead-silicate glass (material science)
    In soda-lime-silica glasses, if lime is replaced by lead oxide (PbO) and if potash (K2O) is used as a partial replacement for soda, lead-alkali-silicate glasses result that have lower softening points than lime glasses. The refractive indices, dispersive powers, and electrical resistance of these glasses are generally much greater than those of soda-lime-silica glasses....
  • alkalic rock (geology)
    ...and (in the case of the carbonatite deposit at Palabora in South Africa) copper sulfide ore minerals. The origin of carbonatite magma is obscure. Most carbonatites occur close to intrusions of alkaline igneous rocks (those rich in potassium or sodium relative to their silica contents) or to the ultramafic igneous rocks (rocks with silica contents below approximately 50 percent by weight)......
  • alkaline cell (battery)
    The highest power density (watts per cubic cm) of the zinc–manganese dioxide cells is found in batteries with an alkaline electrolyte, which permits a completely different type of construction. The alkaline battery became commercially available during the 1950s and is now the most popular household battery. A cathode of a very pure manganese dioxide–graphite mixture and an anode of.....
  • alkaline extraction (chemistry)
    In the following stage an alkaline extraction with dilute caustic soda dissolves chlorinated compounds, which are then washed out....
  • alkaline fuel cell (device)
    These are devices that, by definition, have an aqueous solution of sodium hydroxide or potassium hydroxide as the electrolyte. The fuel is almost always hydrogen gas, with oxygen (or oxygen in air) as the oxidizer. However, zinc or aluminum could be used as an anode if the by-product oxides were efficiently removed and the metal fed continuously as a strip or as a powder. Fuel cells generally......
  • alkaline hydrolysis (chemical reaction)
    ...lubricants that resisted extreme pressures. These were commonly used in mechanical transmissions, high-speed machinery, and precision instruments. The oil was also hardened to make textile sizings. Saponification yielded fatty acids for soap manufacture and fatty alcohols for cosmetics and detergents....
  • alkaline phosphatase (enzyme)
    enzyme that is normally present in high concentrations in growing bone and in bile. It is essential for the deposition of minerals in the bones and teeth. Alkaline phosphatase deficiency is a hereditary trait called hypophosphatasia, which results in bone deformities. In severe cases, the deficiency leads to early death from infection. Alkaline phosphatase is also present in th...
  • alkaline plutonic rock (mineralogy)
    ...of sodium and potassium [(Na,K)AlSiO4]. It is sometimes used as a substitute for feldspars in the manufacture of glass and ceramics. Nepheline is the characteristic mineral of alkaline plutonic rocks, particularly nepheline syenites and nepheline gneisses. It occurs in beautiful crystal form with mica, garnet, and sanidine feldspar on Monte Somma, Vesuvius, Italy. For......
  • alkaline rock (geology)
    ...and (in the case of the carbonatite deposit at Palabora in South Africa) copper sulfide ore minerals. The origin of carbonatite magma is obscure. Most carbonatites occur close to intrusions of alkaline igneous rocks (those rich in potassium or sodium relative to their silica contents) or to the ultramafic igneous rocks (rocks with silica contents below approximately 50 percent by weight)......
  • alkaline solution (chemical compound)
    any of the soluble hydroxides of the alkali metals—i.e., lithium, sodium, potassium, rubidium, and cesium. Alkalies are strong bases that turn litmus paper from red to blue; they react with acids to yield neutral salts; and they are caustic and in concentrated form are corrosive to organic tissues. The term alkali is also applied to the soluble hydroxides of such alkaline-earth meta...
  • alkaline storage battery (electronics)
    In secondary batteries of this type, electric energy is derived from the chemical action in an alkaline solution. Such batteries feature a variety of electrode materials; some of the more notable ones are briefly discussed in this section....
  • alkaline-earth metal (chemical element)
    any of the six chemical elements that comprise Group 2 (IIa) of the periodic table (see ). The elements are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra)....
  • alkalinity (chemistry)
    abnormally low level of acidity, or high level of alkalinity, in the body fluids, including the blood. Alkalosis may be either metabolic or respiratory in origin. Metabolic alkalosis results from either acid loss (which may be caused by severe vomiting or by the use of potent diuretics [substances that promote production of urine]) or bicarbonate gain (which may be caused by excessive intake of......
  • alkaloid (chemical compound)
    any of a class of naturally occurring organic nitrogen-containing bases. Alkaloids have diverse and important physiological effects on humans and other animals. Well-known alkaloids include morphine, strychnine, quinine, ephedrine, and nicotine....
  • alkalophile (bacteria)
    ...especially under anaerobic conditions, and, as a result, plant polymers degrade slowly in acidic (pH between 3.7 and 5.5) bogs, pine forests, and lakes. In contrast to acidophilic bacteria, alkalophilic bacteria are able to grow in alkaline concentrations as great as pH 10 to 11. Alkalophiles have been isolated from soils, and most are species of the gram-positive genus ......
  • alkalosis (pathology)
    abnormally low level of acidity, or high level of alkalinity, in the body fluids, including the blood. Alkalosis may be either metabolic or respiratory in origin. Metabolic alkalosis results from either acid loss (which may be caused by severe vomiting or by the use of potent diuretics [substances that promote production of urine]) or bicarb...
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