A-Z Browse

  • radiosity (optical technique)
    ...illuminated not only directly by a light source such as the Sun or a lamp but also more diffusely by reflected light from other objects. This type of lighting is re-created in computer graphics by radiosity techniques, which model light as energy rather than rays and which look at the effects of all the elements in a scene on the appearance of each object. For example, a brightly coloured......
  • radiosonde (instrument)
    balloon-borne instrument for making atmospheric measurements, such as temperature, pressure, and humidity, and radioing the information back to a ground station. Special helium-filled meteorological balloons made of high-quality neoprene rubber are employed for elevating the radiosonde to very high altitudes of around 30,000 m (100,000 feet); maximum altitude for balloon-borne radiosondes is abou...
  • radiotelegraphy (communications)
    radio communication by means of Morse Code or other coded signals. The radio carrier is modulated by changing its amplitude, frequency, or phase in accordance with the Morse dot-dash system or some other code. At the receiver the coded modulation is recovered by an appropriate demodulator and the code groups are converted into the corresponding symbols. In ma...
  • radiotelephone (communications)
    In addition to the wireline telephones described in Development of the telephone instrument, there exist a number of wireless instruments that are connected to the public switched telephone network (PSTN). At the present time, these wireless telephones generally fall into one of three categories: cordless telephones, cellular radio systems, or personal communication systems. Eventually these......
  • radiotelephony (communications)
    In addition to the wireline telephones described in Development of the telephone instrument, there exist a number of wireless instruments that are connected to the public switched telephone network (PSTN). At the present time, these wireless telephones generally fall into one of three categories: cordless telephones, cellular radio systems, or personal communication systems. Eventually these......
  • Radiotelevision Luxembourg (Luxembourger broadcasting company)
    ...grand duchy’s newspapers express diverse political points of view—conservative, liberal, socialist, and communist. Luxembourg’s influence is felt far beyond its borders through the medium of Radiotelevision Luxembourg (RTL), a privately owned broadcasting company that transmits radio programs in five languages and television programs in two (French and German). RTL has a to...
  • Radiotelevisione Italiana (Italian public service broadcaster)
    The origin and development of Radiotelevisione Italiana (RAI) is discussed above. Regular television broadcasts began in January 1954. RAI has three radio services on national networks on AM and FM: a First, or National, Program offering a balanced output; a Second Program essentially of entertainment; and a Third Program, which is educational. In addition, there is a substantial regional......
  • radiotherapy
    use of radiation sources in the treatment or relief of diseases. Radiation therapy almost always makes use of ionizing radiation, deep tissue-penetrating rays, which can physically and chemically react with diseased cells to destroy them. The other forms of radiation, infrared and ultraviolet, can be employed in heat lamps for neuritis and a...
  • radiothorium (chemical isotope)
    ...William Ramsay, who was interested in radioactivity. While working on a crude radium preparation that Ramsay had given to him to purify, Hahn showed that a new radioactive substance, which he called radiothorium, was present. Fired by this early success and encouraged by Ramsay, who thought highly of him, he decided to continue with research on radioactivity rather than go into industry. With.....
  • radiotracer method (medicine)
    There are techniques that measure metabolism in the myocardium using the radiotracer method (i.e., a radioactive isotope replaces a stable element in a compound, which is then followed as it is distributed through the body). Positron emission tomography uses positron radionuclides that can be incorporated into true metabolic substrates and consequently can be used to chart the course of......
  • radioulnar joint (anatomy)
    ...ulna bones of the forearm. The wrist is composed of eight or nine small, short bones (carpal bones) roughly arranged in two rows. The wrist is also made up of several component joints: the distal radioulnar joint, which acts as a pivot for the forearm bones; the radiocarpal joint, between the radius and the first row of carpal bones, involved in wrist flexion and extension; the midcarpal......
  • radiowave
    Cellular telephones are transportable by vehicle or personally portable devices that may be used in motor vehicles or by pedestrians. Communicating by radiowave in the 800–900-megahertz band, they permit a significant degree of mobility within a defined serving region that may be hundreds of square kilometres in area. In this section, the concept of cellular radio and the development of......
  • radish (plant)
    (Raphanus sativus), annual or biennial plant in the family Brassicaceae that is grown for its large, succulent root. The edible part of the root, together with some of the seedling stem, forms a structure varying in shape, among varieties, from spherical, through oblong, to long cylindrical or tapered. The outside colour of the root varies from white, through pink, to red, purple, and blac...
  • Radishchev, Aleksandr Nikolayevich (Russian author)
    writer who founded the revolutionary tradition in Russian literature and thought....
  • Radisson, Pierre Esprit (French explorer)
    French explorer and fur trader who served both France and England in Canada....
  • radium (chemical element)
    radioactive chemical element, heaviest of the alkaline-earth metals of main Group 2 (IIa) of the periodic table. Radium is a silvery white metal that does not occur free in nature....
  • radium emanation (chemical element)
    chemical element, a heavy radioactive gas of Group 18 (noble gases) of the periodic table, generated by the radioactive decay of radium. Radon is a colourless gas, 7.5 times heavier than air and more than 100 times heavier than hydrogen. The gas liquefies at −61.8 °C (...
  • Radium Hospital (hospital, Paris, France)
    ...1906 Henri Becquerel, the French physicist who discovered radioactivity, accidentally burned himself by carrying radioactive materials in his pocket. Noting that, Pierre Curie, the co-discoverer of radium, deliberately produced a similar burn on himself. Beginning about 1925, a number of women employed in applying luminescent paint that contained radium to clock and instrument dials became ill....
  • radium-224 (chemical isotope)
    Other radioisotopes do not belong to the uranium series. For example, radium-224, which is deposited mainly on bone surfaces, has been used in Europe to treat ankylosing spondylitis. Because of its short half-life (3.6 days), it affects only the bone surface and not the bone marrow. Its major toxicity is the production of bone cancer. Like uranium-238, plutonium-239, which is used in some......
  • radium-226 (chemical isotope)
    ...the water solubility of the uranium compound. Water-soluble forms mainly cause kidney injury, while the insoluble forms produce fibrosis and cancer of the lung. Because of its similarity to calcium, radium-226 is stored mainly in the bone, and it produces abnormal changes in the bone marrow, including anemia and leukemia, cancers of the bone, and paranasal sinuses. The next radioisotope in the....
  • radius (bone)
    in anatomy, the outer of the two bones of the forearm when viewed with the palm facing forward. All land vertebrates have this bone. In humans it is shorter than the other bone of the forearm, the ulna....
  • radius (mathematics)
    Consider a coordinate system, as shown in Figure 8A, with the circle centred at the origin. At any instant of time, the position of the particle may be specified by giving the radius r of the circle and the angle θ between the position vector and the x-axis. Although r is constant, θ increases uniformly with time t, such that θ....
  • radius, atomic (physics)
    half the distance between the nuclei of identical neighbouring atoms. An atom has no rigid spherical boundary, but it may be thought of as a tiny, dense positive nucleus surrounded by a diffuse negative cloud of electrons. The value of atomic radii depends on the type of chemical bond in which the atoms are involved (metallic, ionic, or covalent bond). When the neighbouring atoms are not alike, a...
  • radius gauge (measurement instrument)
    Flush-pin gauges have one moving part and are used to gauge the depth of shoulders or holes. Form gauges are used to check the profile of objects; two of the most common types are radius gauges, which are packs of blades with both concave and convex circular profiles that are used to check the radii of grooves and corners, and screw-thread pitch gauges, which are blades with triangular......
  • radius of convergence (mathematics)
    .... . . converges to a specific function, that function will be the required solution of the problem. The largest value of ε for which the sequence converges is called the radius of convergence of the solution....
  • radius of gyration (physics)
    where k is a distance called the radius of gyration. Comparison to equation (79) shows that k is a measure of how far from the centre of mass the mass of the body is concentrated. Using equations (87) and (88) in equation (86), one finds that...
  • radix (number systems)
    in mathematics, an arbitrarily chosen whole number greater than 1 in terms of which any number can be expressed as a sum of that base raised to various powers. See numerals and numeral systems....
  • radja (government office)
    ...wife’s clan until full bridewealth is paid. Identified by a common ancestor and a geographic location, clans traditionally acted also as political units until the Dutch instituted the office of radja. Originally the Ngada recognized a high god (Déva) and his female component (Nitu), but since 1920 missionaries have worked among the Ngada, and today many Ngada are Roman......
  • Radke, Lina (German athlete)
    German athlete who set several middle-distance running records between 1927 and 1930. Her victory in the 800-metre race at the 1928 Olympic Games—the first Olympics to include women’s athletics—set a world record that was not broken for 16 years....
  • Radke-Batschauer, Karoline (German athlete)
    German athlete who set several middle-distance running records between 1927 and 1930. Her victory in the 800-metre race at the 1928 Olympic Games—the first Olympics to include women’s athletics—set a world record that was not broken for 16 years....
  • Radkowsky, Alvin (American-Israeli physicist)
    American-born Israeli nuclear physicist (b. June 30, 1915, Elizabeth, N.J.—d. Feb. 17, 2002, Tel Aviv, Israel), helped build the world’s first nuclear-powered submarine, the USS Nautilus, in the early 1950s and, later in his career, worked on developing a nuclear reactor fuel that would produce a minimal amount of radioactive waste. Radkowsky studied electrical engine...
  • Radloff, Wilhelm (German anthropologist)
    German scholar and government adviser who made fundamental contributions to the knowledge of the ethnography, folklore, culture, ancient texts, and linguistics of the Turkic peoples of Southern Siberia and Central Asia....
  • Radlov, Vasily Vasilyevich (German anthropologist)
    German scholar and government adviser who made fundamental contributions to the knowledge of the ethnography, folklore, culture, ancient texts, and linguistics of the Turkic peoples of Southern Siberia and Central Asia....
  • Radner, Gilda (American actress and comedienne)
    ...Stir Crazy (1980), and for two flops, See No Evil, Hear No Evil (1989) and Another You (1991). He appeared with his wife, comedian Gilda Radner, in such films as Hanky Panky (1982), The Woman in Red (1984), and Haunted Honeymoon (1986). Following Radner...
  • Radnitz, Gerty Theresa (American biochemist)
    Krebs received a medical degree from Washington University (St. Louis, Mo.) in 1943. From 1946 to 1948 he did research there under the biochemists Carl and Gerty Cori. In 1948 he joined the faculty of biochemistry at the University of Washington, Seattle, becoming full professor in 1957. In 1968 he moved to the University of California at Davis, returning to Washington University in 1977....
  • Radnitzky, Emmanuel (American photographer)
    photographer, painter, and filmmaker who was the only American to play a major role in both the Dada and Surrealist movements....
  • Radnorshire (historical county, Wales, United Kingdom)
    historic county, east-central Wales, on the English border. It covers an area of mountainous terrain and highlands, including Radnor Forest, with a central valley formed by the River Wye. Radnorshire lies completely within the present county of Powys....
  • Radnóti, Miklós (Hungarian author)
    ...and Socialist ideas were expressed in great poetic tableaux and in poems probing the subconscious, and by Gyula Illyés, who found inspiration in the life of the peasantry. The poetry of Miklós Radnóti reached a tragic climax in the serene and polished poems he wrote in the last years of his life....
  • Radom (Poland)
    city, Mazowieckie województwo (province), east-central Poland. It is a rail junction and an administrative and industrial centre; the economy of the city relies predominantly on textile milling, glass- and chemical works, munitions and footwear manufacturing, and food processing. Radom has a museum, a theatre, and a school of engineering....
  • Radom, Confederation of (Polish history)
    ...overthrown Peter in mid-1762) transferred Repnin to Warsaw, where he tried to assert Russia’s dominance over the weak Polish government. In pursuit of this goal he encouraged the formation of the Confederation of Radom (June 1767), an armed league of pro-Russian Polish nobles who opposed their king. When the confederation seized Warsaw and summoned a Sejm (parliament, or diet; 1768), Rep...
  • radome (protective enclosure)
    Some radio telescopes, particularly those designed for operation at very short wavelengths, are placed in protective enclosures called radomes that can nearly eliminate the effect of both wind loading and temperature differences throughout the structure. Special materials that exhibit very low absorption and reflection of radio waves have been developed for such structures, but the cost of......
  • Radomir Rebellion (Bulgarian history)
    ...use his influence to restore order among the troops. Stamboliyski, however, joined the uprising and, at the village of Radomir, where rebel troops were encamped, proclaimed Bulgaria a republic. The Radomir Rebellion was short-lived, as the Agrarian-led assault on Sofia was repulsed by German and Macedonian forces that remained loyal to the tsar. But this provided only a temporary respite. The.....
  • Radomyslsky, Ovsel Gershon Aronov (Russian revolutionary)
    revolutionary who worked closely with Lenin in the Bolshevik Party before the Russian Revolution of 1917 and became a central figure in the Communist Party leadership in the Soviet Union in the 1920s. He later was a victim of Joseph Stalin’s Great Purge....
  • radon (chemical element)
    chemical element, a heavy radioactive gas of Group 18 (noble gases) of the periodic table, generated by the radioactive decay of radium. Radon is a colourless gas, 7.5 times heavier than air and more than 100 times heavier than hydrogen. The gas liquefies at −61.8 °C (...
  • radon-219 (chemical isotope)
    ...observed in 1899 by the British scientists Robert B. Owens and Ernest Rutherford, who noticed that some of the radioactivity of thorium compounds could be blown away by breezes in the laboratory. Radon-219 (actinon; 3.92-second half-life), which is associated with actinium, was found independently in 1904 by German chemist Friedrich O. Giesel and French physicist André-Louis Debierne.......
  • radon-220 (chemical isotope)
    Radon-220 (thoron; 51.5-second half-life) was first observed in 1899 by the British scientists Robert B. Owens and Ernest Rutherford, who noticed that some of the radioactivity of thorium compounds could be blown away by breezes in the laboratory. Radon-219 (actinon; 3.92-second half-life), which is associated with actinium, was found......
  • radon-222 (chemical isotope)
    ...consists of three isotopes, one from each of the three natural radioactive-disintegration series (the uranium, thorium, and actinium series). Discovered in 1900 by German chemist Friedrich E. Dorn, radon-222 (3.823-day half-life), the longest-lived isotope, arises in the uranium series. The name radon is sometimes reserved for this isotope to distinguish it from the other two natural......
  • Radonezhsky, Svyatoy Sergy (Russian saint)
    Russian Orthodox monk whose spiritual doctrine and social programs made him one of Russia’s most respected spiritual leaders. His monastery of the Trinity became the Russian centre and symbol of religious renewal and national identity....
  • Radopholus similis
    ...symptoms are a slow decline, yellowing and dying of leaves, and dieback of twigs and branches in many groves 15 years or older. Infested nursery stock has widely distributed the nematode. The burrowing nematode (Radopholus similis) is a serious endoparasite in tropical and subtropical areas, where it attacks citrus (causing spreading decline), banana, avocado, tomato, black pepper,......
  • Radoslavov, Vasil (Bulgarian official)
    When World War I began, Bulgaria declared strict neutrality, but the tsar and a Germanophile government under Vasil Radoslavov encouraged both sides to bid for Bulgarian intervention. In this contest, the Central Powers (Austria-Hungary and the German empire) could offer far more at the expense of Serbia, Greece, and, later, Romania, than could the Triple Entente (an alliance of Great Britain,......
  • Radowitz, Joseph Maria von (Prussian diplomat)
    conservative Prussian diplomat and general who was the first statesman to attempt the unification of Germany under Prussian hegemony (from 1847), anticipating Otto von Bismarck’s more successful efforts by almost 20 years....
  • Radu Negru (Transylvanian prince)
    ...and northeast by the Transylvanian Alps, on the west, south, and east by the Danube River, and on the northeast by the Seret River. Traditionally it is considered to have been founded in 1290 by Radu Negru (“Radu the Black”), a voivode (or military governor) of Făgăraş in southern Transylvania (then part of Hungary), who crossed the......
  • Radu the Black (Transylvanian prince)
    ...and northeast by the Transylvanian Alps, on the west, south, and east by the Danube River, and on the northeast by the Seret River. Traditionally it is considered to have been founded in 1290 by Radu Negru (“Radu the Black”), a voivode (or military governor) of Făgăraş in southern Transylvania (then part of Hungary), who crossed the......
  • radula (mollusk anatomy)
    horny, ribbonlike structure found in the mouths of all mollusks except the bivalves. The radula, part of the odontophore, may be protruded, and it is used in drilling or in rasping food particles from a surface. It is supported by a cartilage-like mass and is covered with rows of many small teeth (denticles). New sections are constantly produced to replace those worn away at the front....
  • radulae (mollusk anatomy)
    horny, ribbonlike structure found in the mouths of all mollusks except the bivalves. The radula, part of the odontophore, may be protruded, and it is used in drilling or in rasping food particles from a surface. It is supported by a cartilage-like mass and is covered with rows of many small teeth (denticles). New sections are constantly produced to replace those worn away at the front....
  • radulas (mollusk anatomy)
    horny, ribbonlike structure found in the mouths of all mollusks except the bivalves. The radula, part of the odontophore, may be protruded, and it is used in drilling or in rasping food particles from a surface. It is supported by a cartilage-like mass and is covered with rows of many small teeth (denticles). New sections are constantly produced to replace those worn away at the front....
  • Rădulescu, Ion Heliade (Romanian author)
    Transylvanian Latinism crossed the Carpathians and had beneficial effects on the Greek-inspired culture of Walachia. Ion Heliade Rădulescu, who came under this influence, founded the first Romanian newspaper in Walachia and the Societatea Filarmonică (1833), which later created a national theatre in Bucharest. He was a pioneer of Italian influence, which was taken up in Moldavia......
  • Radunitsa (work by Yesenin)
    ...he became acquainted with Aleksandr Blok, the peasant poet Nikolay Klyuyev, and revolutionary politics. In 1916 he published his first book, characteristically titled for a religious feast day, Radunitsa (“Ritual for the Dead”). It celebrates in church book imagery the “wooden Russia” of his childhood, a world blessed by saints in painted icons, where storks n...
  • radurization (radiation)
    The dose of radiation used on food products is divided into three levels. Radappertization is a dose in the range of 20 to 30 kilograys, necessary to sterilize a food product. Radurization is a dose of 1 to 10 kilograys, that, like pasteurization, is useful for targeting specific pathogens. Radicidation involves doses of less than 1 kilogray for extending shelf life and inhibiting sprouting....
  • Raḍwā, Mount (mountain, Saudi Arabia)
    ...coast. In Midian (Madyan), the northernmost part of the Hejaz, the peaks have a maximum elevation of nearly 9,500 feet. The elevation decreases to the south, with an occasional upward surge such as Mount Raḍwā west of Medina (Al-Madīnah). Wadi Al-Ḥamḍ, an intermittent river drawing water from the Medina Basin on the inner side of the escarpment, breaks......
  • Radziwiłł, Catherine (Polish aristocrat)
    His last years were soured by an unfortunate relationship with an aristocratic adventuress, Princess Radziwiłł, who sought to manipulate Rhodes and Milner and even Lord Salisbury, the English prime minister, to promote her ideas of the British Empire. Rhodes was unused to scheming women, nor could the young bachelors surrounding him protect him from her. She forged letters and......
  • Radziwiłł family (Polish family)
    an important Polish–Lithuanian princely family that played a significant role in Polish–Lithuanian history....
  • Radziwiłł, Janusz (Polish prince)
    The magnates and gentry of Great Poland capitulated to the Swedes in July 1655. Prince Janusz Radziwiłł, a leading Calvinist and the greatest magnate of Lithuania, hard-pressed by the Russians, broke off the union with Poland and signed one with Sweden. His motives were a combination of Lithuanian and Protestant interests coloured by his own ambition to rule the grand duchy....
  • Rāe Bareli (district, India)
    Rāe Bareli district, 1,777 sq mi (4,603 sq km) in area, is a stretch of fairly level plain drained principally by the Sai and Ganges rivers. There are extensive forests, with mango and mahua groves. Crops include rice, wheat, barley, and millet. Pop. (1981) town, 89,697; district, 1,886,940....
  • Rāe Bareli (India)
    town, administrative headquarters of Rāe Bareli district, Uttar Pradesh state, northern India, southeast of Lucknow, on the Sai River. Named for the Bhar people, it is a road and rail junction and an agricultural trade centre. Industries include the milling of agricultural products and handloom weaving. The town contains a 15th-century fort and other ancient buildings....
  • Rae, John (Scottish explorer)
    physician and explorer of the Canadian Arctic....
  • Rae, John (American economist and physician)
    Scottish-born American economist, physician, and teacher....
  • Raeburn, Sir Henry (Scottish painter)
    leading Scottish portrait painter during the late 18th and early 19th centuries....
  • raeda (carriage)
    ...individuals. The two most widely used vehicles were the two-wheeled chariot drawn by two or four horses and its companion, the cart used in rural areas. A four-wheeled raeda in its passenger version corresponded to the stagecoaches of a later period and in its cargo version to the freight wagons. Fast freight raedae......
  • Raeder, Erich (German naval officer)
    commander in chief of the German Navy (1928–43) and proponent of an aggressive naval strategy, who was convicted as a war criminal for his role in World War II....
  • Raedwald (king of the East Angles)
    king of the East Angles in England from the late 6th or early 7th century, son of Tytili....
  • Raegnald I (king of York)
    Meanwhile another danger had arisen: Norsemen from Ireland had been settling for some time west of the Pennines, and Northumbria was threatened by Raegnald, a Norse leader from Dublin, who made himself king at York in 919. Edward built fortresses at Thelwall and Manchester, and in 920 he received Raegnald’s submission, along with that of the Scots, the Strathclyde Welsh, and all the......
  • Raemaekers, Louis (Dutch cartoonist)
    Dutch cartoonist who gained international fame with his anti-German cartoons during World War I....
  • Raeren brownware (German pottery)
    ...with pewter or silver mounts. The Doppelfrieskrüge were jugs with two molded friezes (usually portraying classical subjects) around the middle. They and the tankards were made in Raeren brownware by Jan Emens, surnamed Mennicken, in the last quarter of the 16th century. Emens also worked in the gray body that was used at Raeren at the turn of the century, employing blue......
  • Raeti (ancient people)
    ...tribes invaded the eastern Alps about 400 bc and eventually founded the kingdom of Noricum, the first “state” on Austrian territory known by name. In the west, however, the ancient Raetian people were able to maintain their seat (see Raetian language). Then, attracted by the rich iron resources and the strategic importance of the region, the Romans began to as...
  • Raetia (ancient province, Europe)
    ancient Roman province comprising Vorarlberg and Tirol states in present-day Austria, the eastern cantons of Switzerland, and parts of Bavaria and Baden-Württemberg states in Germany. Its native inhabitants were probably of mixed Illyrian and Celtic stock. The area was conquered by Rome in 15 bc and became an important part of the empire, but not for its economic value, which ...
  • Raetian language
    language spoken by the ancient Raetians in southern Germany and in the Alpine regions of Italy, Austria, and Switzerland in pre-Roman times. The language is known from a number of inscriptions....
  • Raetic language
    language spoken by the ancient Raetians in southern Germany and in the Alpine regions of Italy, Austria, and Switzerland in pre-Roman times. The language is known from a number of inscriptions....
  • Raeto-Romance languages
    group of Romance dialects spoken in Switzerland and northern Italy. The most important Rhaetian dialects are Sursilvan and Sutsilvan, which together make up the Romansh language. Other Rhaetian dialects are Engadine, spoken in Switzerland in the Inn River valley; Ladin, spoken in the Alto Adige and Dolom...
  • RAF (British air force)
    youngest of the three British armed services, charged with the air defense of the United Kingdom and the fulfillment of international defense commitments....
  • RAF (German radical leftist group)
    West German radical leftist group formed in 1968 and popularly named after two of its early leaders, Andreas Baader (1943–77) and Ulrike Meinhof (1934–76)....
  • Raff and Gammon (American company)
    ...continuous 47-foot (14-metre) film loop ran on spools between an incandescent lamp and a shutter for individual viewing. Starting in 1894, Kinetoscopes were marketed commercially through the firm of Raff and Gammon for $250 to $300 apiece. The Edison Company established its own Kinetograph studio (a single-room building called the “Black Maria” that rotated on tracks to follow the...
  • Raff, Joachim (German composer)
    German composer and teacher, greatly celebrated in his lifetime but nearly forgotten in the late 20th century....
  • Raff, Joseph Joachim (German composer)
    German composer and teacher, greatly celebrated in his lifetime but nearly forgotten in the late 20th century....
  • Raffaelle ware (pottery)
    tin-glazed earthenware produced from the 15th century at such Italian centres as Faenza, Deruta, Urbino, Orvieto, Gubbio, Florence, and Savona. Tin-glazed earthenware—also made in other countries, where it is called faience, or delft—was introduced into Italy from Moorish Spain by way of the island of Majorca, or Maiolica, whence it derived the name by which it was...
  • Raffaello Sanzi (Italian painter and architect)
    master painter and architect of the Italian High Renaissance. Raphael is best known for his Madonnas (see ) and for his large figure compositions in the Vatican in Rome. His work is admired for its clarity of form and ease of composition and for its visual achievement of the Neoplatonic ideal of human grandeur....
  • Raffarin, Jean-Pierre (prime minister of France)
    When newly reelected Pres. Jacques Chirac named Jean-Pierre Raffarin prime minister of France on May 6, 2002, fewer than half the French people knew who the latter was. That, of course, was the Gaullist president’s point....
  • Raffi (Armenian author)
    celebrated Armenian novelist....
  • raffia palm (tree)
    ...tigillarium and Calamus erinaceus (and, in Borneo, Daemonorops longispathus) are found. In the Amazon estuary Raphia taedigera covers extensive areas; other species of the raffia palm dominate similar habitats in West Africa. The raffia palm occurs in nearly pure stands between marsh and dicotyledonous swamp forests along the Caribbean and Pacific coasts of Costa Ric...
  • raffinose (carbohydrate)
    ...are glucose, fructose, and galactose; disaccharides include sucrose (table sugar), lactose (milk sugar), and maltose. A slightly more complex type of carbohydrate is the oligosaccharide (e.g., raffinose and stachyose), which contains three to 10 saccharide units; these compounds, which are found in beans and other legumes and cannot be digested well by humans, account for the gas-producing......
  • Raffles, Sir Stamford (British colonial agent)
    British East Indian administrator and founder of the port city of Singapore (1819), who was largely responsible for the creation of Britain’s Far Eastern empire. He was knighted in 1816....
  • Raffles, Sir Thomas Stamford (British colonial agent)
    British East Indian administrator and founder of the port city of Singapore (1819), who was largely responsible for the creation of Britain’s Far Eastern empire. He was knighted in 1816....
  • Rafflesia (plant genus)
    The family Rafflesiaceae includes the following genera, mostly in the Old World subtropics: Pilostyles (22 species), Bdallophytum (4 species), Apodanthes (5 species), Rafflesia (12 species), Cytinus (6 species), Rhizanthes (1 or 2 species), and Sapria (1 or 2 species)....
  • Rafflesia arnoldii (plant)
    The flowers are well developed, however, and range in size from minute to extremely large. The monster flower (Rafflesia arnoldii), with the largest known flower, is parasitic upon the roots of Tetrastigma species, large vines of the grape family (Vitaceae) found in the forested mountains of Malaysia. Its fully developed flower appears above ground as a thick, fleshy, five-lobed......
  • Rafflesiaceae (plant family)
    plant family in the Malpighiales order, notable for being strictly parasitic upon the roots or stems of other plants and for the remarkable growth forms exhibited as adaptations to this mode of nutrition. The vegetative organs of most are so reduced and modified that the plant body exists only as a network of threadlike cellular strands living almost wholly within the tissues of the host plant. Th...
  • Rafflesiales (plant order)
    plant family in the Malpighiales order, notable for being strictly parasitic upon the roots or stems of other plants and for the remarkable growth forms exhibited as adaptations to this mode of nutrition. The vegetative organs of most are so reduced and modified that the plant body exists only as a network of threadlike cellular strands living almost wholly within the tissues of the host plant. Th...
  • Rafi (political party, Israel)
    The third partner was Rafi (an acronym for Reshimat Poʿale Yisraʾel [“Israel Workers List”]), formed in 1965 when Ben-Gurion, after a political and personal feud with Eshkol, withdrew with his supporters to form a new party. Although most Rafi members joined the new Israel Labour Party in 1968, Ben-Gurion and a few followers formed their own tiny party, known as the Sta...
  • Rāfiʿ al-Darajāt (Mughal emperor)
    ...and violated the age-old Mughal notion of statecraft. In Farrukh-Siyar’s place the brothers raised to the throne three young princes in quick succession within eight months in 1719. Two of these, Rafīʿ al-Darajāt and Rafīʿ al-Dawlah (Shah Jahān II), died of consumption. The third, who assumed the title Muḥammad Shah, exhibited sufficient v...
  • Rāfiʿ ibn Harthama (Iranian rebel)
    ...Mecca when they passed through Baghdad. But ʿAmr remained useful to Baghdad so long as Khorāsān was victimized by the rebels Aḥmad al-Khujistānī and, for longer, Rāfiʿ ibn Harthama. After Rāfiʿ had been finally defeated in 896, ʿAmr’s broader ambitions gave the caliph al-Muʿtaḍid his chance. ...
  • Rafīʿ-ud-Dawlah (Mughal emperor)
    ...place the brothers raised to the throne three young princes in quick succession within eight months in 1719. Two of these, Rafīʿ al-Darajāt and Rafīʿ al-Dawlah (Shah Jahān II), died of consumption. The third, who assumed the title Muḥammad Shah, exhibited sufficient vigour to set about freeing himself from the brothers’ control....

Link to this article and share the full text with the readers of your Web site or blog-post.

If you think a reference to this article on "" will enhance your Web site, blog-post, or any other web-content, then feel free to link to this article, and your readers will gain full access to the full article, even if they do not subscribe to our service.

You may want to use the HTML code fragment provided below.

copy link

We welcome your comments. Any revisions or updates suggested for this article will be reviewed by our editorial staff. Contact us here.

Regular users of Britannica may notice that this comments feature is less robust than in the past. This is only temporary, while we make the transition to a dramatically new and richer site. The functionality of the system will be restored soon.

A-Z Browse

Image preview