• Amistad (film by Spielberg [1997])

    Steven Spielberg: The 1990s: Amistad (1997) found Spielberg in social historian mode. The film centers on the slave revolt that took place aboard the Spanish slave ship Amistad in 1839 and the subsequent trial in the United States for which the slaves were tried for insurrection on the high…

  • Amistad (slave ship)

    John Quincy Adams: Second career in Congress of John Quincy Adams: …arrested aboard the slave ship Amistad—enslaved people who had mutinied and escaped from their Spanish owners off the coast of Cuba and had wound up bringing the ship into United States waters near Long Island, New York. Adams defended them as freemen before the Supreme Court in 1841 against efforts…

  • Amistad Dam (dam, United States-Mexico)

    Rio Grande: The economy: The international Amistad Dam, below the confluence of Devils River, was completed in 1969 under terms of a U.S.-Mexico treaty. Considerable amounts of hydroelectricity are produced within the basin.

  • Amistad mutiny (North American-African history)

    Amistad mutiny, (July 2, 1839), slave rebellion that took place on the slave ship Amistad near the coast of Cuba and had important political and legal repercussions in the American abolition movement. The mutineers were captured and tried in the United States, and a surprising victory for the

  • Amistad, Puente de la (bridge, Brazil-Paraguay)

    Ciudad del Este: …Puente de la Amistad (“Friendship Bridge”; opened 1964), and its association with the nearby Itaipú Dam on the Paraguay-Brazil border, which is one of the largest hydroelectric facilities in the world. Because of the presence of smugglers and the Islamic militant group Hezbollah in the region in the early…

  • Amisus (Turkey)

    Samsun, city, capital of Samsun il (province), northern Turkey. The largest city on the southern coast of the Black Sea, Samsun lies between the deltas of the Kızıl and Yeşil rivers. Amisus, which stood on a promontory just northwest of the modern city center, was founded in the 7th century bce;

  • Amitabh Bachchan Corporation Ltd. (Indian company)

    Amitabh Bachchan: Financial difficulties: He later headed Amitabh Bachchan Corporation Ltd. (ABCL), an entertainment venture that specialized in film production, distribution, and event management. ABCL organized the Miss World beauty pageant in 1996 in Bengaluru and produced a successful sitcom called Dekh Bhai Dekh (1993–94; “Look, Brother, Look”). The business was plagued…

  • Amitabha (sculpture by Jōchō)

    Jōchō: The Amida (Amitabha) of the Hōō-dō (Phoenix Hall), of the Byōdō Temple at Uji, near Kyōto, is his only extant work. Carved in 1053, it embodies tranquillity and gracefulness, effects achieved by Jōchō’s brilliant use of the joined-wood technique.

  • Amitabha (Buddhism)

    Amitabha, in Mahayana Buddhism, and particularly in the so-called Pure Land sects, the great saviour buddha. As related in the Sukhavati-vyuha-sutras (the fundamental scriptures of the Pure Land sects), many ages ago a monk named Dharmakara made a number of vows, the 18th of which promised that, on

  • Amitābha Triad (Japanese art)

    Japanese art: Painting: One fresco depicting an Amida (Amitabha) Triad shows graceful figures rendered with comparative naturalism and defined with consistent, unmodulated brush lines known as “wire lines” (tessen-byō). Like the Hōryū pagoda sculptures, the wall paintings suggest the influence of Tang style.

  • Amitāyur-dhyāna-sūtra (Buddhist text)

    Amitāyur-dhyāna-sūtra, (Sanskrit: “Discourse Concerning Meditation on Amitāyus”), one of three texts basic to Pure Land Buddhism. Together with the larger and smaller Sukhāvatī-vyūha-sūtras (Sanskrit: “Description of the Western Paradise Sutras”), this text envisions rebirth in the celestial Pure

  • Amitayus (Buddhism)

    Amitabha, in Mahayana Buddhism, and particularly in the so-called Pure Land sects, the great saviour buddha. As related in the Sukhavati-vyuha-sutras (the fundamental scriptures of the Pure Land sects), many ages ago a monk named Dharmakara made a number of vows, the 18th of which promised that, on

  • Amitāyus-vipaśyana-sūtra (Buddhist text)

    Pure Land Buddhism: …on three Sanskrit scriptures: the Amitāyus-vipaśyana-sūtra (“Discourse Concerning Meditation on Amitāyus”) and the “larger” and “smaller” Pure Land sutras (Sukhāvatī-vyūha-sūtras [“Description of the Western Paradise Sutras”]). These texts relate the story of the monk Dharmakara, the future Amitayus, or Amitabha, who made a series of vows that were meant to…

  • Amitermes meridionalis (insect)

    termite: Nest types: In northern Australia Amitermes meridionalis builds wedge-shaped mounds, called compass or magnetic mounds, that are 3 to 4 metres (9.8 to 13.1 feet) high, 2.5 metres (8.1 feet) wide, and 1 metre (3.2 feet) thick at the base. The long axis is always directed north-south, and the broad…

  • Amiternum (ancient town, Italy)

    Amiternum, in ancient Italy, a Sabine town 5 miles (8 km) north of present L’Aquila in the Aterno (ancient Aternus) River valley. It was stormed by the Romans in 293 bc, but the fertility of its fields helped it to regain its prosperity as a Roman municipality (municipium), especially under the

  • amitraksar (Indian poetry)

    Michael Madhusudan Dutt: …it was he who introduced amitraksar (a form of blank verse with run-on lines and varied caesuras), the Bengali sonnet—both Petrarchan and Shakespearean—and many original lyric stanzas. Despite his literary success, Dutt continued to struggle financially. He went to England in 1862 to study law and was eventually called to…

  • amitriptyline (drug)

    antidepressant: The tricyclics include imipramine, amitriptyline, desipramine, nortriptyline, and a number of other compounds. These drugs relieve symptoms in a high proportion (more than 70 percent) of depressed patients. As with the MAOIs, the antidepressant action of tricyclic drugs may not become apparent until two to four weeks after treatment…

  • Amitrochates (Mauryan emperor)

    Bindusara was the second Mauryan emperor, who ascended the throne about 297 bce. Greek sources refer to him as Amitrochates, Greek for the Sanskrit amitraghata (“destroyer of foes”). The name perhaps reflects his successful campaign in the Deccan. Chandragupta—Bindusara’s father and founder of the

  • Amity Commerce and Navigation, Treaty of (United States-Great Britain [1794])

    Jay Treaty, (November 19, 1794), agreement that assuaged antagonisms between the United States and Great Britain, established a base upon which America could build a sound national economy, and assured its commercial prosperity. Negotiations were undertaken because of the fears of Federalist

  • Amityville Horror, The (film by Rosenberg [1979])

    Stuart Rosenberg: Films of the 1970s: …Rosenberg found box-office success with The Amityville Horror (1979). The thriller was based on Jay Anson’s nonfiction book about a Long Island house that was allegedly possessed by demons. James Brolin and Margot Kidder starred as the homeowners, and Rod Steiger was the priest who tries to exorcize the forces…

  • Amizade Bridge (bridge, Brazil-Paraguay)

    Ciudad del Este: …Puente de la Amistad (“Friendship Bridge”; opened 1964), and its association with the nearby Itaipú Dam on the Paraguay-Brazil border, which is one of the largest hydroelectric facilities in the world. Because of the presence of smugglers and the Islamic militant group Hezbollah in the region in the early…

  • Amizhou (China)

    Kaiyuan, city, southern Yunnan sheng (province), southwestern China. It was established in 1276 as Amizhou prefecture during the Yuan dynasty (1206–1368). In 1913 it was made a county under the same name. It was renamed Kaiyuan in 1931 and has been a county-level city since 1981. Kaiyuan is the

  • Amkhadzhyr (work by Chanba)

    Samson Chanba: …the first original Abkhazian play, Amkhadzhyr. It recounts the exodus, forced by tsarist Russia during the 19th century, of Abkhazians to the Ottoman Empire. He went on to write several more plays in Russian and Abkhaz, including Lady Abkhazia (1923) and From Past Days (1929). His major work of the…

  • AML (Algerian organization)

    Ferhat Abbas: …et de la Liberté (AML; Friends of the Manifesto and Liberty), which envisioned an Algerian autonomous republic federated to a renewed, anti-colonial France. After the suppression of the AML and a year’s imprisonment, in 1946 he founded the Union Démocratique du Manifeste Algérien (UDMA; Democratic Union of the Algerian Manifesto),…

  • AML (pathology)

    blood disease: Leukemia: In acute myelogenous leukemia (AML), the predominant cells are the youngest recognizable precursors (myeloblasts) of the neutrophils of the blood. In a third and the least common variety, acute monocytic leukemia, the immature cells appear to be precursors of the monocytes of the blood. Myelogenous and…

  • Amleth (work by Saxo Grammaticus)

    Saxo Grammaticus: His legend of Amleth is thought to be the source of William Shakespeare’s Hamlet; his Toke, the archer, the prototype of William Tell. Saxo incorporated also myths of national gods whom tradition claimed as Danish kings, as well as myths of foreign heroes. Three heroic poems are especially…

  • AMLO (president of Mexico)

    Andrés Manuel López Obrador is a center-left populist Mexican politician who was president of Mexico from 2018 to 2024. The founder of the National Regeneration Movement political party, he was the first person in a century not from either the Institutional Revolutionary Party or the National

  • ʿAmm (Arabian deity)

    Arabian religion: South Arabia: …Sabaʾ the national god was Almaqah (or Ilmuqah), a protector of artificial irrigation, lord of the temple of the Sabaean federation of tribes, near the capital, Maʾrib. Until recently, Almaqah was considered to be a moon god, under the influence of a now generally rejected conception of a South Arabian…

  • Amma (Dogon god)

    Amma, the supreme creator god in the religion of the Dogon people of West Africa. The notion of a creator god named Amma or Amen is not unique to the Dogon but can also be found in the religious traditions of other West African and North African groups. It may be reflected in the name Amazigb,

  • Amma’s Egg (religion)

    Amma: …refer to this body as Amma’s Egg and characterize it as a conical, somewhat quadrangular structure with a rounded point and as filled with unrealized potentiality; its corners prefigure the four future cardinal points of the universe to come. According to Dogon myth, some undefined impulse caused this egg to…

  • ʿAmmān (national capital, Jordan)

    Amman, capital and largest city of Jordan. It is the residence of the king and the seat of government. The city is built on rolling hills at the eastern boundary of the ʿAjlūn Mountains, on the small, partly perennial Wadi ʿAmmān and its tributaries. Amman’s focus of settlement throughout history

  • Amman (national capital, Jordan)

    Amman, capital and largest city of Jordan. It is the residence of the king and the seat of government. The city is built on rolling hills at the eastern boundary of the ʿAjlūn Mountains, on the small, partly perennial Wadi ʿAmmān and its tributaries. Amman’s focus of settlement throughout history

  • Amman, Jost (German engraver)

    Jost Amman was a painter and printmaker, one of the most prolific and skilled book illustrators of the 16th century. Amman was educated in Zürich and worked for a short time in Basel, where he designed glass paintings for prominent families. About 1560–61 he moved to Nürnberg but retained his

  • Ammaniti, Niccolò (Italian author)

    Italian literature: Fiction at the turn of the 21st century: …tamer successes of the market—are Niccolò Ammaniti, Tiziano Scarpa, Isabella Santacroce, Aldo Nove (pseudonym of Antonello Satta Centanin), Simona Vinci, Daniele Luttazzi, Silvia Ballestra, Luisa Brancaccio, Francesca Mazzucato, Matteo Galiazzo, and Carlo Lucarelli. Ammaniti’s Io non ho paura (2001, film 2003; I’m Not Scared) chronicles a young boy’s loss of…

  • Ammann, Jakob (Swiss religious leader)

    Amish: …17th century among followers of Jakob Ammann.

  • Ammann, Othmar Herman (American engineer)

    Othmar Herman Ammann was an engineer and designer of numerous long suspension bridges, including the Verrazano-Narrows Bridge over New York harbour, at its completion (1965) the longest single span in the world. In 1904 Ammann immigrated to the United States, where he helped design railroad

  • Ammann, Simon (Swiss ski jumper)

    Simon Ammann is a Swiss ski jumper who won the individual normal hill and the individual large hill gold medals at both the 2002 and 2010 Olympic Winter Games, becoming the first man to sweep the individual ski jumping events at two Olympics. Ammann began ski jumping at age 11, learning the sport

  • Ammannati, Bartolommeo (Italian sculptor and architect)

    Bartolommeo Ammannati was an Italian sculptor and architect whose buildings mark the transition from the classicizing Renaissance to the more exuberant Baroque style. Ammannati began his career as a sculptor, carving statues in various Italian cities in the 1530s and ’40s. He trained first under

  • Ammassalik (Greenland)

    Tasiilaq, town, southeastern Greenland, on the south coast of Ammassalik Island. The island is 25 miles (40 km) long and 12–20 miles (19–32 km) wide, with a high point of 4,336 feet (1,322 metres). Although Europeans landed as early as 1472, the region was not explored until 1884, when Gustav Holm,

  • ʿamme ha-aretz (Judaism)

    Talmud and Midrash: Legend and folklore: …those in the countryside (the ʿam ha-aretz, or “people of the land”). The rabbis realized the great danger involved in this situation and developed their own folk material. They adopted the dramatic and artistic parts of these stories but rejected the unwanted elements, replacing them with their own ideas. Thus…

  • Ammers-Küller, Jo van (Dutch author)

    Jo van Ammers-Küller was a Dutch writer best known for her historical novels. Van Ammers-Küller began her writing career as a playwright. Her first successful novels, Het huis der vreugden (1922; The House of Joy) and Jenny Huysten (1923; Jenny Huysten’s Career), deal with life in and around the

  • Ammers-Küller, Johanna van (Dutch author)

    Jo van Ammers-Küller was a Dutch writer best known for her historical novels. Van Ammers-Küller began her writing career as a playwright. Her first successful novels, Het huis der vreugden (1922; The House of Joy) and Jenny Huysten (1923; Jenny Huysten’s Career), deal with life in and around the

  • ammeter (measurement instrument)

    ammeter, instrument for measuring either direct (DC) or alternating (AC) electric current, in amperes. An ammeter can measure a wide range of current values because at high values only a small portion of the current is directed through the meter mechanism; a shunt in parallel with the meter carries

  • Ammianus Marcellinus (Roman historian)

    Ammianus Marcellinus was the last major Roman historian, whose work continued the history of the later Roman Empire to 378. Ammianus was born of a noble Greek family and served in the army of Constantius II in Gaul and Persia under the general Ursicinus, who was dismissed after he allowed the

  • Ammiṣaduqa (king of Babylonia)

    history of Mesopotamia: Babylonian law: Ammiṣaduqa (c. 1646–c. 1626 bce) comes a century and a half after Hammurabi. His edict, already referred to, lists, among others, the following social and economic factors: private debts in silver and grain, if arising out of loans, were canceled; also canceled were back taxes…

  • ammocoete (zoology)

    chordate: Digestion and nutrition: …the vertebrates in the “ammocoetes” larva stage of the primitive jawless fish called the lamprey. The difference is that the food consists of somewhat larger particles that have been deposited on the bottom (detritus), and, instead of the feeding current being driven by cilia, the pharyngeal musculature pumps water…

  • Ammodorcas clarkei (mammal)

    dibatag, (Ammodorcas clarkei), a rare member of the gazelle tribe (Antilopini, family Bovidae), indigenous to the Horn of Africa. The dibatag is sometimes mistaken for the related gerenuk. A selective browser with a narrow, pointed snout, the dibatag is long-legged and long-necked. It stands 80–88

  • Ammodramus savannarum (bird)

    finch: …monotonously unmusical notes of the grasshopper sparrow (Ammodramus savannarum). Many kinds of finches are kept as cage birds.

  • Ammókhostos (Cyprus)

    Famagusta, major port in the Turkish Cypriot-administered portion of northern Cyprus. It lies on the island’s east coast in a bay between Capes Greco and Eloea and is about 37 miles (55 km) east of Nicosia. The port possesses the deepest harbor in Cyprus. Famagusta is a Frankish corruption of its

  • Ammon (Egyptian god)

    Amon, Egyptian deity who was revered as king of the gods. Amon may have been originally one of the eight deities of the Hermopolite creation myth; his cult reached Thebes, where he became the patron of the pharaohs by the reign of Mentuhotep I (2008–1957 bce). At that date he was already identified

  • ammonal (chemical compound)

    ammonium nitrate: …an oxidizing agent in the ammonals, which are mixtures of ammonium nitrate and powdered aluminum.

  • Ammonas (Christian hermit)

    patristic literature: Monastic literature: …in the Egyptian desert, and Ammonas (flourished c. 350), his successor as leader of his colony of anchorites (hermits), wrote numerous letters; a handful from the pen of each is extant, almost entirely in Greek or Latin translation of the Coptic originals. Those of Ammonas are particularly valuable for the…

  • ammonia (chemical compound)

    ammonia (NH3), colourless, pungent gas composed of nitrogen and hydrogen. It is the simplest stable compound of these elements and serves as a starting material for the production of many commercially important nitrogen compounds. The major use of ammonia is as a fertilizer. In the United States,

  • ammonia dynamite (explosive)

    ammonium nitrate: …as nitroglycerin in the so-called ammonia dynamites, or as an oxidizing agent in the ammonals, which are mixtures of ammonium nitrate and powdered aluminum.

  • ammonia inhalants (preparation)

    smelling salts, any of several different preparations of ammonia-based product and other ingredients used to revive a person affected by syncope (fainting). Historically, smelling salts contained ammonium carbonate and perfume; modern preparations typically consist of ammonia dissolved in water and

  • ammonia maser (device)

    laser: Energy levels and stimulated emissions: …conceivable system, such as the ammonia maser built by Townes, has only two energy levels. More useful laser systems involve three or four energy levels. In a three-level laser, the material is first excited to a short-lived high-energy state that spontaneously drops to a somewhat lower-energy state with an unusually…

  • ammonia-beam maser (device)

    laser: Energy levels and stimulated emissions: …conceivable system, such as the ammonia maser built by Townes, has only two energy levels. More useful laser systems involve three or four energy levels. In a three-level laser, the material is first excited to a short-lived high-energy state that spontaneously drops to a somewhat lower-energy state with an unusually…

  • ammonia-soda process (chemical process)

    ammonia-soda process, modern method of manufacturing the industrial alkali sodium carbonate, also known as soda ash. The process was devised and first put to commercial use by Ernest Solvay, who built a plant in 1865 in Couillet, Belg., and was improved in the 1870s by the German-born British

  • ammonia-stripping (chemical process)

    wastewater treatment: Removal of plant nutrients: A physicochemical process called ammonia stripping may be used to remove ammonia from sewage. Chemicals are added to convert ammonium ions into ammonia gas. The sewage is then cascaded down through a tower, allowing the gas to come out of solution and escape into the air. Stripping is less…

  • ammonification (biology)

    biosphere: The nitrogen cycle: …organic nitrogen into ammonia (ammonification), providing a constant supply of ammonia to be used in the process of nitrification. Although the fixation of atmospheric nitrogen is an essential part of the nitrogen cycle, ammonification and nitrification are the predominant methods by which organic nitrogen is prevented from returning to…

  • ammonite (fossil cephalopod)

    ammonoid, any of a group of extinct cephalopods (of the phylum Mollusca), forms related to the modern pearly nautilus (Nautilus), that are frequently found as fossils in marine rocks dating from the Devonian Period (began 419 million years ago) to the Cretaceous Period (ended 66 million years ago).

  • Ammonite (film by Lee [2020])

    Mary Anning: Belated acknowledgment and legacy: In the film Ammonite (2020), the character of Anning is played by actress Kate Winslet.

  • Ammonite (people)

    Ammonite, any member of an ancient Semitic people whose principal city was Rabbath Ammon, in Palestine. The “sons of Ammon” were in perennial, though sporadic, conflict with the Israelites. After a long period of seminomadic existence, the Ammonites established a kingdom north of Moab in the 13th

  • Ammonite scroll border (pottery ornament)

    pottery: Turkish: …pattern, which was called the Ammonite scroll border because it was thought to resemble the coiled shell of the fossil ammonite but which is certainly a debased version of the Ming Rock of Ages pattern. This scroll border appears often; a slightly later and even more debased version, which incorporates…

  • ammonium alum (chemical compound)

    alum: Ammonium alum is produced by the evaporation of a water solution containing ammonium sulfate and aluminum sulfate. It can also be obtained by treating a mixture of aluminum sulfate and sulfuric acid with ammonia. Alums occur naturally in various minerals. Potassium alum, for example, is…

  • ammonium aluminum sulfate (chemical compound)

    alum: Ammonium alum is produced by the evaporation of a water solution containing ammonium sulfate and aluminum sulfate. It can also be obtained by treating a mixture of aluminum sulfate and sulfuric acid with ammonia. Alums occur naturally in various minerals. Potassium alum, for example, is…

  • ammonium chloride (chemical compound)

    ammonium chloride (NH4Cl), the salt of ammonia and hydrogen chloride. Its principal uses are as a nitrogen supply in fertilizers and as an electrolyte in dry cells, and it is also extensively employed as a constituent of galvanizing, tinning, and soldering fluxes to remove oxide coatings from

  • ammonium cyanate (chemical compound)

    urea: …German chemist Friedrich Wöhler from ammonium cyanate in 1828 was the first generally accepted laboratory synthesis of a naturally occurring organic compound from inorganic materials. Urea is now prepared commercially in vast amounts from liquid ammonia and liquid carbon dioxide. These two materials are combined under high pressures and elevated…

  • ammonium dihydrogen phosphate (chemical compound)

    electricity: Piezoelectricity: …quartz, 5 × −10−11 for ammonium dihydrogen phosphate, and 3 × 10−10 for lead zirconate titanate.

  • ammonium hydrosulfide (chemical compound)

    Jupiter: Cloud composition: …they probably consist of condensed ammonium hydrosulfide and that their colour may be caused by other ammonia-sulfur compounds such as ammonium polysulfides. Sulfur compounds are invoked as the likely colouring agents because sulfur is relatively abundant in the cosmos and hydrogen sulfide is notably absent from Jupiter’s atmosphere above the…

  • ammonium hydroxide (chemical compound)

    ammonium hydroxide, solution of ammonia gas in water, a common commercial form of ammonia. It is a colourless liquid with a strong characteristic odour. In concentrated form, ammonium hydroxide can cause burns on contact with the skin; ordinary household ammonia, used as a cleanser, is actually

  • ammonium ion (chemical ion)

    acid–base reaction: The Brønsted–Lowry definition: …ions (cations), such as the ammonium ion (NH4+), which can be derived by the addition of a proton to a molecular base, in this case ammonia (NH3). The hydronium ion (H3O+), which is the hydrogen ion in aqueous solution, also belongs to this class. The charge of these ionic acids,…

  • ammonium molybdate (chemical compound)

    molybdenum processing: Chemically pure molybdic oxide: …suitable for the manufacture of ammonium molybdate (ADM) and sodium molybdate, which are starting materials for all sorts of molybdenum chemicals. These compounds are obtained by reacting chemically pure MoO3 with aqueous ammonia or sodium hydroxide. Ammonium molybdate, in the form of white crystals, assays 81 to 83 percent MoO3,…

  • ammonium nitrate (chemical compound)

    ammonium nitrate, (NH4NO3), a salt of ammonia and nitric acid, used widely in fertilizers and explosives. The commercial grade contains about 33.5 percent nitrogen, all of which is in forms utilizable by plants; it is the most common nitrogenous component of artificial fertilizers. Ammonium nitrate

  • ammonium nitrate fuel oil mixture (explosive)

    explosive: Ammonium nitrate–fuel oil mixtures: In 1955 it was discovered that mixtures of ammonium nitrate and fine coal dust would give very satisfactory blasting results in the large (about 22.5-centimetre, 9-inch) holes used in open-pit coal mines to remove the rock and soil covering the coal.…

  • ammonium paratungstate (chemical compound)

    tungsten processing: Ammonium paratungstate: Tungsten ores frequently occur in association with sulfides and arsenides, which can be removed by roasting in air for two to four hours at 800° C (1,450° F). In order to produce ammonium paratungstate (APT), an intermediate compound in production of the pure…

  • ammonium picrate (chemical compound)

    chemical industry: Nitric acid: Another explosive ingredient is ammonium picrate, derived from picric acid, the relationship of which appears more clearly in its systematic name, 2,4,6-trinitrophenol.

  • ammonium polysulfide (chemical compound)

    Jupiter: Cloud composition: …other ammonia-sulfur compounds such as ammonium polysulfides. Sulfur compounds are invoked as the likely colouring agents because sulfur is relatively abundant in the cosmos and hydrogen sulfide is notably absent from Jupiter’s atmosphere above the clouds.

  • ammonium sulfate (chemical compound)

    chromium processing: Chromium metal: …based on a solution of ammonium sulfate recycled from a later stage in the process, and sulfuric acid. The resultant slurry is cooled, and silica and other undissolved solids are filtered from the solution. The iron forms crude ferrous ammonium sulfate crystals, which also are filtered out. The mother liquor…

  • ammonium thiosulfate (chemical compound)

    technology of photography: Fixing: …contains a chemical (sodium or ammonium thiosulfate) that converts the silver halide into soluble, complex silver salts that dissolve in the fixer. During this process the film loses its original silver halide milkiness overlaying the image and becomes clear. The fixer also contains a weak acid (to halt the development…

  • Ammonius Hermiae (Greek philosopher)

    Ammonius Hermiae was a Greek philosopher whose thinking was primarily oriented toward logic and the sciences. He spent a good part of his intellectual life in writing critical works on Aristotle. As a student, he worked closely with Proclus and, later in life, was appointed the head of the

  • Ammonius Saccas (Neoplatonic philosopher)

    Origen: Life: …Origen attended lectures given by Ammonius Saccas, the founder of Neoplatonism. A letter of Origen mentions his “teacher of philosophy,” at whose lectures he met Heraclas, who was to become his junior colleague, then his rival, and who was to end as bishop of Alexandria refusing to hold communion with…

  • ammonoid (fossil cephalopod)

    ammonoid, any of a group of extinct cephalopods (of the phylum Mollusca), forms related to the modern pearly nautilus (Nautilus), that are frequently found as fossils in marine rocks dating from the Devonian Period (began 419 million years ago) to the Cretaceous Period (ended 66 million years ago).

  • Ammonoida (fossil cephalopod)

    ammonoid, any of a group of extinct cephalopods (of the phylum Mollusca), forms related to the modern pearly nautilus (Nautilus), that are frequently found as fossils in marine rocks dating from the Devonian Period (began 419 million years ago) to the Cretaceous Period (ended 66 million years ago).

  • Ammonoidea (fossil cephalopod)

    ammonoid, any of a group of extinct cephalopods (of the phylum Mollusca), forms related to the modern pearly nautilus (Nautilus), that are frequently found as fossils in marine rocks dating from the Devonian Period (began 419 million years ago) to the Cretaceous Period (ended 66 million years ago).

  • Ammons, A.R. (American poet)

    A.R. Ammons was an American poet who was one of the leading late 20th-century exponents of the Transcendentalist tradition. A 1949 graduate of Wake Forest College (now University), Ammons worked as an elementary school principal and as a glass company executive before turning his full attention to

  • Ammons, Albert (American musician)

    boogie-woogie: …with inventing the term itself, Albert Ammons, Pete Johnson, and Meade “Lux” Lewis.

  • Ammons, Archie Randolph (American poet)

    A.R. Ammons was an American poet who was one of the leading late 20th-century exponents of the Transcendentalist tradition. A 1949 graduate of Wake Forest College (now University), Ammons worked as an elementary school principal and as a glass company executive before turning his full attention to

  • Ammons, Eugene (American musician)

    Gene Ammons was an American jazz tenor saxophonist, noted for his big sound and blues-inflected, “soulful” improvising. The son of outstanding boogie-woogie pianist Albert Ammons, Gene Ammons grew up in Chicago and first became nationally known as a member of Billy Eckstine’s innovative bebop big

  • Ammons, Gene (American musician)

    Gene Ammons was an American jazz tenor saxophonist, noted for his big sound and blues-inflected, “soulful” improvising. The son of outstanding boogie-woogie pianist Albert Ammons, Gene Ammons grew up in Chicago and first became nationally known as a member of Billy Eckstine’s innovative bebop big

  • Ammons, Jug (American musician)

    Gene Ammons was an American jazz tenor saxophonist, noted for his big sound and blues-inflected, “soulful” improvising. The son of outstanding boogie-woogie pianist Albert Ammons, Gene Ammons grew up in Chicago and first became nationally known as a member of Billy Eckstine’s innovative bebop big

  • Ammophila (plant)

    beach grass, (genus Ammophila), genus of two species of sand-binding plants in the grass family (Poaceae). American beach grass (Ammophila breviligulata) grows along the Atlantic coast and in the Great Lakes region of North America. European beach grass (A. arenaria) is native to temperate coasts

  • Ammophila arenaria (plant)

    beach grass: European beach grass (A. arenaria) is native to temperate coasts in Europe, northern Africa, and western Asia and has been introduced in many places as a dune stabilizer. While native beach grass is protected by law in some areas, both species are considered invasive species…

  • Ammophila breviligulata (plant)

    beach grass: American beach grass (Ammophila breviligulata) grows along the Atlantic coast and in the Great Lakes region of North America. European beach grass (A. arenaria) is native to temperate coasts in Europe, northern Africa, and western Asia and has been introduced in many places as a…

  • Ammospermophilus (rodent)

    ground squirrel: Nontropical ground squirrels: …populated by five species of antelope ground squirrel (genus Ammospermophilus). The white-tailed antelope squirrel (A. leucurus) of the southwestern United States is one of the smallest of all ground squirrels, weighing 96 to 117 grams (3.4 to 4 ounces) and having a body up to 17 cm (6.7 inches) long…

  • Ammospermophilus leucurus (rodent)

    ground squirrel: Nontropical ground squirrels: The white-tailed antelope squirrel (A. leucurus) of the southwestern United States is one of the smallest of all ground squirrels, weighing 96 to 117 grams (3.4 to 4 ounces) and having a body up to 17 cm (6.7 inches) long and a tail of less than…

  • Ammotragus lervia (mammal)

    aoudad, (Ammotragus lervia), North African goatlike mammal of the family Bovidae (order Artiodactyla). This species has been inappropriately called a sheep, although recent genetic information reveals that it is much more closely related to wild goats. The aoudad stands about 102 cm (40 inches) at

  • ammoxidation (chemical process)

    nitrile: …quantities by a process called ammoxidation that depends on the oxidation of propylene in the presence of ammonia and a catalyst. Acrylonitrile constitutes an important component of several polymeric substances, including the acrylic textile fibres and synthetic rubbers and thermoplastic resins.

  • ammunition

    ammunition, the projectiles and propelling charges used in small arms, artillery, and other guns. Ammunition size is usually expressed in terms of calibre, which is the diameter of the projectile as measured in millimetres or inches. In general, projectiles less than 20 mm or .60 inch in diameter

  • Amne Machin (mountains, China)

    Min Mountains: …far west are called the Amne Machin (Jishi Mountains), and those in the north are called the Xiqing Mountains. The central section of the range lying west of the Min River, which has an axis running from north to south, is known as the Qionglai Mountains. The easternmost section, which…