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  • silicate (chemical compound)

    traditional ceramics: Raw materials: …most cases these materials are silicates—that is, compounds based on silica (SiO2), an oxide form of the element silicon. In fact, so common is the use of silicate minerals that traditional ceramics are often referred to as silicate ceramics, and their manufacture is often called the silicate industry. Many of…

  • silicate glass (material science)

    industrial glass: Chemical properties: …entire network may occur when silicate glasses are attacked by caustic alkalis and by hydrofluoric, phosphoric, and perchloric acids. The general approach to improving the chemical durability of glass is to make the surface as silica-rich as possible. This can be accomplished by two methods: fire polishing, a procedure that…

  • silicate layer (mineralogy)

    clay mineral: General features: …“backbones” of clay minerals called silicate layers. The unit silicate layer formed by aligning one octahedral sheet to one tetrahedral sheet is referred to as a 1:1 silicate layer, and the exposed surface of the octahedral sheet consists of hydroxyls. In another type, the unit silicate layer consists of one…

  • silicate mineral

    Silicate mineral, any of a large group of silicon-oxygen compounds that are widely distributed throughout much of the solar system. A brief treatment of silicate minerals follows. For full treatment, see mineral: Silicates. The silicates make up about 95 percent of Earth’s crust and upper mantle,

  • silicate perovskite (mineral)

    high-pressure phenomena: Earth science: …a diamond-anvil cell to synthesize silicate perovskite, a dense form of the common mineral enstatite, MgSiO3. Subsequent studies by Liu revealed that many of the minerals believed to constitute the deep interior of the Earth transform to the perovskite structure at lower mantle conditions—an observation that led him to propose…

  • silicate tetrahedron (mineralogy)

    amphibole: Crystal structure: …silicate mineral structures is the silicon-oxygen tetrahedron (SiO4)4-. It consists of a central silicon atom surrounded by four oxygen atoms in the shape of a tetrahedron. The essential characteristic of the amphibole structure is a double chain of corner-linked silicon-oxygen tetrahedrons that extend indefinitely parallel to the c crystallographic axis,…

  • Siliceo, Juan Martínez (Spanish archbishop)

    Spain: The statutes of limpieza: …author of this statute was Juan Martínez Siliceo, archbishop of Toledo, a man of humble and, hence, by definition, untainted origins who had found himself despised by the aristocratic canons, many of whom were of converso ancestry. In 1556 Philip II gave his royal approval to the statute on the…

  • siliceous ooze (marine deposit)

    sedimentary rock: Origin of cherts: …and recrystallizing the organically produced siliceous ooze deposits that accumulate on the present-day abyssal ocean floor. The modern oozes gather in latitudes where high organic productivity of floating planktonic radiolarians and diatoms takes place in the warm surface waters. As individual organisms die, their shells settle slowly to the abyssal…

  • siliceous rock (geology)

    Siliceous rock, any of a group of sedimentary rocks that consist largely or almost entirely of silicon dioxide (SiO2), either as quartz or as amorphous silica and cristobalite; included are rocks that have formed as chemical precipitates and excluded are those of detrital or fragmental origin. The

  • siliceous sinter (mineral)

    silica mineral: Solubility of silica minerals: …silica results in formation of siliceous sinter or geyserite, as at Mammoth Hot Springs in Yellowstone National Park in the western United States.

  • siliceous spicule (biology)

    sponge: Mineral skeletons: Siliceous spicules, found in the Demospongiae and in the Hexactinellida, are made essentially of silicic acid; they also contain some water, a small quantity of other compounds containing sodium, potassium, iron, and chlorine, and a small quantity of organic matter, called spiculin, which forms an…

  • siliceous sponge (invertebrate)

    Siliceous sponge, any sponge in which the main skeletal component is silica as opposed to calcium carbonate or fibrous organic materials only. More than 95 percent of all known sponge species have a siliceous skeleton and belong to the class Demospongiae (phylum Porifera). The siliceous skeleton is

  • silicic acid (chemical compound)

    Silicic acid, a compound of silicon, oxygen, and hydrogen, regarded as the parent substance from which is derived a large family—the silicates—of minerals, salts, and esters. The acid itself, having the formula Si(OH)4, can be prepared only as an unstable solution in water; its molecules readily

  • silicic magma (geology)

    igneous rock: Origin of magmas: The silicic magmas can be formed by a combination of two processes; the presence of water under pressure lowers the melting temperature by as much as 200 °C (392 °F) and thereby expedites magma generation. At a convergent plate boundary, the lower continental crust is heated…

  • silicic rock (igneous rock)

    Felsic and mafic rocks, division of igneous rocks on the basis of their silica content. Chemical analyses of the most abundant components in rocks usually are presented as oxides of the elements; igneous rocks typically consist of approximately 12 major oxides totaling over 99 percent of the rock.

  • siliciclastic rock (geology)

    sedimentary rock: Classification systems: …are also referred to as siliciclastic sedimentary rocks. Siliciclastics are further subdivided on the basis of clast diameter into conglomerate and breccia, sandstone, siltstone, and finer-than-silt-sized mudrock (shale, claystone, and mudstone). The carbonates, limestones and dolomites, consist of the minerals aragonite, calcite, and dolomite. They are chemical sedimentary rocks in…

  • silicle (fruit)

    silique: A silicle, or silicula, is a short and broad silique, as in shepherd’s purse (Capsella). Both types are characteristic of plants in the mustard family.

  • silicomanganese (alloy)

    manganese processing: Silicomanganese: This alloy, containing 65 to 68 percent manganese, 16 to 21 percent silicon, and 1.5 to 2 percent carbon, is produced by the smelting of slag from high-carbon ferromanganese or of manganese ore with coke and a quartz flux. Smelting temperatures are higher than…

  • silicon (chemical element)

    Silicon (Si), a nonmetallic chemical element in the carbon family (Group 14 [IVa] of the periodic table). Silicon makes up 27.7 percent of Earth’s crust; it is the second most abundant element in the crust, being surpassed only by oxygen. The name silicon derives from the Latin silex or silicis,

  • silicon bronze (metallurgy)

    copper processing: Bronze: Silicon bronze usually contains about 96 percent copper. The remainder may be silicon alone, but more often a little manganese, tin, iron, or zinc also is added. These alloys were developed originally for the chemical industry because of their exceptional resistance to corrosion in many…

  • silicon carbide (chemical compound)

    Silicon carbide, exceedingly hard, synthetically produced crystalline compound of silicon and carbon. Its chemical formula is SiC. Since the late 19th century silicon carbide has been an important material for sandpapers, grinding wheels, and cutting tools. More recently, it has found application

  • silicon detector (instrument)

    radiation measurement: Silicon detectors: Silicon detectors with diameters of up to several centimetres and thicknesses of several hundred micrometres are common choices for heavy charged particle detectors. They are fabricated from extremely pure or highly resistive silicon that is mildly n- or p-type owing to residual dopants.…

  • silicon diode detector (instrument)

    radiation measurement: Silicon detectors: Silicon detectors with diameters of up to several centimetres and thicknesses of several hundred micrometres are common choices for heavy charged particle detectors. They are fabricated from extremely pure or highly resistive silicon that is mildly n- or p-type owing to residual dopants.…

  • silicon dioxide (chemical compound)

    Silica, compound of the two most abundant elements in Earth’s crust, silicon and oxygen, SiO2. The mass of Earth’s crust is 59 percent silica, the main constituent of more than 95 percent of the known rocks. Silica has three main crystalline varieties: quartz (by far the most abundant), tridymite,

  • silicon disulfide (chemical compound)

    sulfide: Structure of sulfides: For example, silicon disulfide, SiS2, has a structure consisting of infinite chains of SiS4 tetrahedrons that share edges. (Each SiS4 tetrahedron consists of a central silicon atom surrounded by and bonded to four sulfur atoms.) Phosphorus forms a series of molecular sulfides that includes P4S3, P4S4 (two…

  • silicon epitaxy (crystallography)

    epitaxy: …a crucible or cell for silicon epitaxy, or gallium and arsenic can be placed in separate cells for gallium arsenide epitaxy. In chemical vapour deposition the atoms for epitaxial growth are supplied from a precursor gas source (e.g., silane). Metal-organic chemical vapour deposition is similar, except that it uses metal-organic…

  • Silicon Graphics, Inc. (American company)

    SGI, American manufacturer of high-performance computer workstations, supercomputers, and advanced graphics software with headquarters in Mountain View, California. Silicon Graphics, Inc., was founded in 1982 by James Clark, an electrical-engineering professor at Stanford University who had

  • silicon hydride (chemical compound)

    Silane, any of a series of covalently bonded compounds containing only the elements silicon and hydrogen, having the general formula SinH2n + 2, in which n equals 1, 2, 3, and so on. The silanes are structural analogues of the saturated hydrocarbons (alkanes) but are much less stable. The term

  • Silicon Island (California, United States)

    Alameda, city, Alameda county, California, U.S. It lies on a 6.5-mile- (11-km-) long by 1-mile- (1.6-km-) wide island in San Francisco Bay, across the Oakland Harbor Channel from Oakland, with which it is connected by bridges and underground tunnels. The site was originally a peninsula that was

  • silicon solar cell (physics)

    solar cell: Development of solar cells: …with the development of the silicon solar cell by Russell Ohl in 1941. Thirteen years later, aided by the rapid commercialization of silicon technology needed to fabricate the transistor, three other American researchers—Gerald Pearson, Daryl Chapin, and Calvin Fuller—demonstrated a silicon solar cell capable of a 6 percent energy-conversion efficiency…

  • silicon transistor (electronics)

    transistor: Silicon transistors: During the 1950s, meanwhile, scientists and engineers at Bell Labs and Texas Instruments were developing advanced technologies needed to produce silicon transistors. Because of its higher melting temperature and greater reactivity, silicon was much more difficult to work with than germanium, but it…

  • Silicon Valley (American television program)

    Mike Judge: …of the live-action television series Silicon Valley (2014–19), Judge skewered the tech industry. He later cocreated Mike Judge Presents: Tales from the Tour Bus (2017– ), a documentary series about musicians that included animated interviews and reenactments as well as performance footage.

  • Silicon Valley (region, California, United States)

    Silicon Valley, industrial region around the southern shores of San Francisco Bay, California, U.S., with its intellectual centre at Palo Alto, home of Stanford University. Silicon Valley includes northwestern Santa Clara county as far inland as San Jose, as well as the southern bay regions of

  • silicon-28 (isotope)

    silicon: Properties of the element: …isotopes of silicon are known: silicon-28, which makes up 92.21 percent of the element in nature; silicon-29, 4.70 percent; and silicon-30, 3.09 percent. Five radioactive isotopes are known.

  • silicon-29 (isotope)

    silicon: Properties of the element: …of the element in nature; silicon-29, 4.70 percent; and silicon-30, 3.09 percent. Five radioactive isotopes are known.

  • silicon-30 (isotope)

    silicon: Properties of the element: 70 percent; and silicon-30, 3.09 percent. Five radioactive isotopes are known.

  • silicon-controlled rectifier (electronics)

    stagecraft: Dimmers: …control paved the way for silicon-controlled rectifier (SCR) dimmers.

  • silicon-oxygen tetrahedron (mineralogy)

    amphibole: Crystal structure: …silicate mineral structures is the silicon-oxygen tetrahedron (SiO4)4-. It consists of a central silicon atom surrounded by four oxygen atoms in the shape of a tetrahedron. The essential characteristic of the amphibole structure is a double chain of corner-linked silicon-oxygen tetrahedrons that extend indefinitely parallel to the c crystallographic axis,…

  • silicone (chemical compound)

    Silicone, any of a diverse class of fluids, resins, or elastomers based on polymerized siloxanes, substances whose molecules consist of chains made of alternating silicon and oxygen atoms. Their chemical inertness, resistance to water and oxidation, and stability at both high and low temperatures

  • silicone breast implant

    Silicone breast implant, prosthesis made from a polymer gel contained within a flexible casing that is used for the reconstruction or augmentation of the female mammary tissue. The polymer gel is made up of a chain of alternating silicon and oxygen atoms, which makes the substance highly stable and

  • silicone rubber (chemical compound)

    silicone: Applications: Vulcanized silicone rubber is prepared in two principal forms: (1) as room-temperature-vulcanizing (RTV) elastomers, which are low-molecular-weight liquids that are cast or molded into desired shapes and then interlinked at room temperature, and (2) high-temperature-vulcanizing (HTV) elastomers, which are higher-molecular-weight gums that are mixed and processed…

  • silicosis (disease)

    Silicosis, a chronic disease of the lungs that is caused by the inhalation of silica dust over long periods of time. (Silica is the chief mineral constituent of sand and of many kinds of rock.) Silicosis is a form of pneumoconiosis. The disease occurs most commonly in miners, quarry workers,

  • silicula (fruit)

    silique: A silicle, or silicula, is a short and broad silique, as in shepherd’s purse (Capsella). Both types are characteristic of plants in the mustard family.

  • Silifke (Turkey)

    Silifke, town, south-central Turkey. It is located along the banks of the G?ksu River, overlooking the Taurus Mountains. An irrigation scheme supplying the fertile lowland of the G?ksu delta is located at Silifke. The town is a market centre for agricultural produce of its hinterland, including

  • Siliguri (India)

    Siliguri, city, northern West Bengal state, northeastern India. It lies just west of the Mahananda River. Siliguri is the terminus of the roads from Kalimpang (Kalimpong) and Sikkim and of road and rail connections with Darjiling (Darjeeling) and Jalpaiguri and is the hub for trade with Darjiling,

  • Siling Vandals (people)

    Sevilla: History: The Silingi Vandals made it the seat of their kingdom early in the 5th century ce, but in 461 it passed under Visigothic rule. In 711 the town fell to the Muslims, and under their rule Ixvillia, as it was then called, flourished. It became a…

  • Siling, Lake (lake, China)

    Tibet: Drainage and soils: …(Tibetan: Tangra Yum), Nam, and Siling. South of Lhasa lie two other large lakes, Yamzho Yun (Yangzho Yong) and Puma Yung (Pumo). In western Tibet two adjoining lakes are located near the Nepal border—Lake Mapam, sacred to both Buddhists and Hindus, and Lake La’nga.

  • Silingi Vandals (people)

    Sevilla: History: The Silingi Vandals made it the seat of their kingdom early in the 5th century ce, but in 461 it passed under Visigothic rule. In 711 the town fell to the Muslims, and under their rule Ixvillia, as it was then called, flourished. It became a…

  • silique (fruit)

    Silique, any dry fruit that separates at maturity into two or four segments called valves, leaving a persistent partition that bears the seeds. The valves remain connected at the top. A typical silique is an elongated capsule, such as in cabbage. A silicle, or silicula, is a short and broad

  • Siliquofera grandis (insect)

    katydid: Physical characteristics: Siliquofera grandis, for example, which is among the largest of the katydids, has a wingspan of more than 25 cm (9.8 inches). Other species, however, including some common ones, have short wings or are nearly wingless. As a group, katydids are poor flyers. Many species…

  • Silisili, Mount (mountain, Samoa)

    Savai‘i: …6,095 feet (1,858 metres) at Mount Silisili, its highest point. A string of volcanic craters extends from the east coast at Tuasivi to Samoa’s westernmost point at Cape Mulinu‘u. Eruptions in the early 1900s ruined many plantations on Savai‘i, but the volcanoes have been quiescent since 1911.

  • Silistra (Bulgaria)

    Silistra, town, extreme northeastern Bulgaria, on the Danube River opposite Romania. To the south and southeast are the remains of the old fortifications. The Romans founded a fortified camp at Durostorum in the early 2nd century ad. The medieval town that sprang from it, known as Drastar, stood

  • Silius Italicus (Roman poet)

    Silius Italicus, Latin epic poet whose 17-book, 12,000-line Punica on the Second Punic War (218–201 bc) is the longest poem in Latin literature. Silius was a distinguished advocate in his earlier years. He later took to public service and was a consul in 68, the year of Nero’s death. His

  • Silius, Gaius (Roman noble)

    Claudius: Administrative innovations: …marriage ceremony with her lover, Gaius Silius. Messalina and Silius were killed, and Claudius married his niece Agrippina, an act contrary to Roman law, which he therefore changed. To satisfy Agrippina’s lust for power, Claudius had to adopt her son Lucius Domitius Ahenobarbus (later the emperor Nero), to the disadvantage…

  • Siliyānah (town, Tunisia)

    Siliana, town in northern Tunisia located on the western edge of the Dorsale Mountains. The town is built not far from Maktar (Makthar), an ancient site with megalithic monuments, Numidian ruins, and Roman remains. Lying in a fertile region dominated by the Dorsale Mountains, which extend from the

  • Silja, Lake (lake, Sweden)

    Lake Siljan, lake in the administrative l?n (county) of Dalarna, central Sweden. Covering an area of 112 square miles (290 square km; including Orsa and In lakes, 137 square miles [354 square km]), it is Dalarna’s largest lake. After receiving the ?sterdal River at Mora, the lake stretches for a

  • Siljan structure (impact crater, Sweden)

    Devonian extinctions: The Siljan structure in Sweden, an impact crater about 65 km (about 40 miles) in diameter, has been dated to approximately 377 million years ago. This places the impact within the error range for the estimated boundary between the Frasnian-Famennian stages and also within the Kellwasser…

  • Siljan, Lake (lake, Sweden)

    Lake Siljan, lake in the administrative l?n (county) of Dalarna, central Sweden. Covering an area of 112 square miles (290 square km; including Orsa and In lakes, 137 square miles [354 square km]), it is Dalarna’s largest lake. After receiving the ?sterdal River at Mora, the lake stretches for a

  • silk (in sapphires)

    sapphire: …faint whitish sheen, known as silk. Tiny, regularly arranged mineral inclusions (commonly rutile) and elongate cavities are responsible for the asterism shown by star sapphire.

  • silk (fibre)

    Silk, animal fibre produced by certain insects and arachnids as building material for cocoons and webs, some of which can be used to make fine fabrics. In commercial use, silk is almost entirely limited to filaments from the cocoons of domesticated silkworms (caterpillars of several moth species

  • silk cotton (tree)

    “Flying” Trees: For example, the kapok tree, found in tropical forests throughout the world, is an emergent—a tree whose crown rises well above the canopy. The kapok’s towering height enables it to gain access to winds above the canopy. The tiny seeds of the kapok are attached to fine fibres…

  • silk cotton tree (tree)

    “Flying” Trees: For example, the kapok tree, found in tropical forests throughout the world, is an emergent—a tree whose crown rises well above the canopy. The kapok’s towering height enables it to gain access to winds above the canopy. The tiny seeds of the kapok are attached to fine fibres…

  • silk gland (animal anatomy)

    spider: Silk: …have only two types of silk glands, but orb weavers have at least seven, each of which produces a different kind of silk; e.g., aciniform glands produce silk for wrapping prey, ampullate glands produce the draglines and frame threads, and cylindrical glands produce parts of the egg sac. Epigastric silk…

  • silk oak (tree)

    Silky oak, (Grevillea robusta), large tree native to Australia and also grown as a street tree in warm areas and, in its juvenile stage, as an indoor pot plant. It belongs to the family Proteaceae (see Proteales). In Australia it is cut for timber, but elsewhere it is valued for its graceful,

  • silk plant (plant)

    Albizia, (genus Albizia), genus of trees or shrubs in the pea family (Fabaceae). The genus is pantropical, though most species are native to warm regions of the Old World. The plants are widely used for fodder and timber, and many are important in traditional medicine. Several species are grown as

  • Silk Road (trade route)

    Silk Road, ancient trade route, linking China with the West, that carried goods and ideas between the two great civilizations of Rome and China. Silk went westward, and wools, gold, and silver went east. China also received Nestorian Christianity and Buddhism (from India) via the Silk Road.

  • Silk Road Ensemble (music group)

    Yo-Yo Ma: Soon thereafter he established the Silk Road Ensemble, and the group’s first recording, Silk Road Journeys: When Strangers Meet, was released in 2002. The project’s scope subsequently expanded, using the Silk Road as a metaphor for connecting artistic endeavours worldwide and across cultures. A number of additional recordings by the…

  • Silk Road Project (music group)

    Yo-Yo Ma: Soon thereafter he established the Silk Road Ensemble, and the group’s first recording, Silk Road Journeys: When Strangers Meet, was released in 2002. The project’s scope subsequently expanded, using the Silk Road as a metaphor for connecting artistic endeavours worldwide and across cultures. A number of additional recordings by the…

  • Silk Route (trade route)

    Silk Road, ancient trade route, linking China with the West, that carried goods and ideas between the two great civilizations of Rome and China. Silk went westward, and wools, gold, and silver went east. China also received Nestorian Christianity and Buddhism (from India) via the Silk Road.

  • silk screen (printmaking)

    Silkscreen, sophisticated stenciling technique for surface printing, in which a design is cut out of paper or another thin, strong material and then printed by rubbing, rolling, or spraying paint or ink through the cut out areas. It was developed about 1900 and originally used in advertising and

  • silk screen stenciling

    Robert Rauschenberg: …borrowed from Andy Warhol the silk-screen stencil technique for applying photographic images to large expanses of canvas, reinforcing the images and unifying them compositionally with broad strokes of paint reminiscent of Abstract Expressionist brushwork. These works draw on themes from modern American history and popular culture and are notable for…

  • silk spider (arachnid)

    Silk spider, (genus Nephila), any of a genus of the class Arachnida (phylum Arthropoda), so named because of the great strength of their silk and the golden colour of their huge orb webs. These webs often measure 1 metre (about 3.3 feet) or more in diameter and are suspended between trees by guy

  • Silk Stockings (film by Mamoulian [1957])

    Fred Astaire: Later musicals: Easter Parade, Royal Wedding, and The Band Wagon: …classic MGM musicals ended with Silk Stockings (1957), after which his screen appearances were mostly in nondancing character roles. He continued to dance with new partner Barrie Chase for several Emmy Award-winning television specials throughout the 1950s and ’60s, and he danced again on-screen in Finian’s Rainbow (1968) and for…

  • silk thread (textiles)

    textile: Sewing thread: Silk thread has great elasticity and strength combined with fine diameter. It can be permanently stretched in sewing, and is suitable for silks and wools. Buttonhole twist is a strong, lustrous silk about three times the diameter of normal sewing silk, and is used for…

  • silk tree (plant)

    Albizia, (genus Albizia), genus of trees or shrubs in the pea family (Fabaceae). The genus is pantropical, though most species are native to warm regions of the Old World. The plants are widely used for fodder and timber, and many are important in traditional medicine. Several species are grown as

  • silk tree (plant species)

    albizia: Silk tree, or powderpuff tree (Albizia julibrissin), native to Asia and the Middle East, grows to about 9 metres (30 feet) tall, has a broad spreading crown, and bears flat pods about 12 cm (5 inches) long. Indian albizia, or siris (A. lebbek), native to…

  • Silk, George (American photographer)

    George Silk, New Zealand-born American photographer (born Nov. 17, 1916, Levin, N.Z.—died Oct. 23, 2004, Norwalk, Conn.), worked for Life magazine from 1943 until 1972. He at first was a combat photographer and was one of the first to photograph Nagasaki, Japan, after the atomic bomb was dropped o

  • ?ilka River (river, Russia)

    Shilka River, river, Chita oblast (province), southeastern Russia, formed by the union of the Onon and Ingoda rivers. It flows 348 miles (560 km) northeast to unite with the Argun to form the Amur River on the Russia–China border. The area of its drainage basin is 80,000 square miles (206,000

  • Silkeborg (Denmark)

    Silkeborg, city, eastern Jutland, Denmark, on the Guden? River and Langs?, a small lake, west of ?rhus. An episcopal town of some importance in the Middle Ages, its castle became a royal hunting and fishing base after the Reformation. The present city, dating from 1845 (chartered 1900), grew up

  • silken fungus beetle (insect)

    Silken fungus beetle, (family Cryptophagidae), any of approximately 800 insect species (insect order Coleoptera) in which the adult beetles are less than 5 mm (15 inch) in length, are oval, are yellow or brown, and are covered with fine, silky hairs. These beetles usually feed on fungi and decaying

  • Silken Thomas (Irish leader)

    Thomas Fitzgerald, 10th earl of Kildare, leader of a major Irish rebellion against King Henry VIII of England. The failure of the uprising ended the Fitzgerald family’s hereditary viceroyalty of Ireland and led to the tightening of English control over the country. When his father, the Irish lord

  • Silko, Leslie Marmon (American author)

    Leslie Marmon Silko, Native American poet and novelist whose work often centres on the dissonance between American Indian and white cultures. Silko, of mixed Laguna Pueblo, white, and Mexican ancestry, grew up on the Laguna Pueblo reservation in New Mexico, where she learned Laguna traditions and

  • silkscreen (printmaking)

    Silkscreen, sophisticated stenciling technique for surface printing, in which a design is cut out of paper or another thin, strong material and then printed by rubbing, rolling, or spraying paint or ink through the cut out areas. It was developed about 1900 and originally used in advertising and

  • Silkwood (film by Nichols [1983])

    Nora Ephron: …Alice Arlen, the screenplay for Silkwood (1983), based on the true story of Karen Silkwood (portrayed in the movie by Meryl Streep), a union activist who died while investigating safety violations at a nuclear fuel production plant. Silkwood won Ephron her first Academy Award nomination for best original screenplay. She…

  • Silkwood, Karen (American laboratory technician and activist)

    Karen Silkwood, American laboratory technician and activist who attempted to expose the safety violations and negligence at Kerr-McGee’s Cimarron River nuclear facility and died in a car crash before she was able to present her evidence. The circumstances of her death brought attention to bear on

  • silkworm moth (insect)

    Silkworm moth, (Bombyx mori), lepidopteran whose caterpillar has been used in silk production (sericulture) for thousands of years. Although native to China, the silkworm has been introduced throughout the world and has undergone complete domestication, with the species no longer being found in the

  • silky anteater (mammal)

    anteater: The silky anteater: Also known as the two-toed, pygmy, or dwarf anteater, the silky anteater (Cyclopes didactylus) is the smallest and least-known member of the family. The silky anteater is found from southern Mexico southward to Bolivia and Brazil. It is not rare but is difficult…

  • silky camellia (plant)

    stewartia: Silky camellia, or Virginia stewartia (S. malacodendron), a shrub up to 3.5 metres (11.5 feet) high, has white flowers with purple stamens. Another American species is the mountain stewartia, sometimes called mountain camellia (S. ovata), which is also shrubby; it is mostly confined to the…

  • silky flycatcher (bird)

    Silky flycatcher, (family Ptilogonatidae), any of four arboreal bird species found in dry, brushy regions from Nevada south to Panama that have silky feathers, prominent crests, and broad bills. They are about 19 cm (7.5 inches) long. Their basic diet consists of mistletoe berries, supplemented

  • silky lacewing (insect)

    neuropteran: Annotated classification: Family Psychopsidae (silky lacewings) Adults large mothlike species; antennae short, wings broad. Larvae elongated, flat; head broad posteriorly, closely attached to prothorax; jaws incurved, large, sicklelike; often arboreal, under bark. Family Osmylidae (osmylidflies) Adults medium to large; head wider than long; antennae filiform, short; 3

  • silky lustre (mineralogy)

    mineral: Lustre: …milky quartz may exhibit this); silky, descriptive of the lustre of a skein of silk or a piece of satin and characteristic of some minerals in fibrous aggregates (examples are fibrous gypsum [CaSO4 ? 2H2O], known as satin spar, and chrysotile asbestos [Mg3Si2O5(OH)4]); and adamantine, having the

  • silky oak (tree)

    Silky oak, (Grevillea robusta), large tree native to Australia and also grown as a street tree in warm areas and, in its juvenile stage, as an indoor pot plant. It belongs to the family Proteaceae (see Proteales). In Australia it is cut for timber, but elsewhere it is valued for its graceful,

  • silky osier (tree)

    willow: … fastigiata) is a variety especially common at Xochimilco near Mexico City.

  • silky pocket mouse (rodent)

    pocket mouse: Natural history: The nine species of silky pocket mice (genus Perognathus) are very small, weighing from 5 to 30 grams (0.2 to 1.1 ounces) and having a body length of 6 to 9 cm (2.4 to 3.5 inches) and hairy tails 5 to 10 cm long. Silky pocket mice have soft…

  • silky terrier (breed of dog)

    Silky terrier, Australian breed of toy dog, first shown in 1907. It originated in Sydney and was once known as the Sydney silky. A rather low-set dog, the silky terrier stands 9 to 10 inches (23 to 25.5 cm) and weighs 8 to 10 pounds (3.5 to 4.5 kg). Its silky, fine coat is glossy blue-gray and tan,

  • sill (geology)

    Sill, flat intrusion of igneous rock that forms between preexisting layers of rock. Sills occur in parallel to the bedding of the other rocks that enclose them, and, though they may have vertical to horizontal orientations, nearly horizontal sills are the most common. Sills may measure a fraction

  • Sill, Anna Peck (American educator)

    Anna Peck Sill, American educator who opened and administered a girls’ school that would become Rockford College. Sill began teaching school at the age of 20, and in 1843 she opened a seminary in Warsaw, New York. From 1846 to 1849 she headed the female department of the Cary Collegiate Institute

  • Silla (ancient kingdom, Korea)

    Silla, one of the three kingdoms of ancient Korea and the one that in 668 unified Korea under the Unified Silla dynasty (q.v.; 668–935). Silla is traditionally believed to have been founded by Hy?kk?se in 57 bc. By the 2nd century ad, a distinct confederation of local tribes was definitely in

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    perciform: Annotated classification: Family Sillaginidae (whitings) Oligocene to present. Elongated fishes with long, conical snout, small mouth; moderately long dorsal and anal fins; anal fin with 2 weak spines. About 31 species of small marine fishes of shallow water; Indo-Pacific, often in estuaries and river mouths; dig in bottom…

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