276 résultats pour "located"
-
Fire - chemistry.
were usually natural caves. Eventually people learned to dip branches in pitch to form torches. They created crude lamps by filling a hollowed out piece of stone withmoss soaked in oil or tallow (a substance derived from animal fat). By cooking with fire, prehistoric people made the meat of the animals they killed more palatable and digestible. They learned to preserve meat by smoking it over a fire,vastly decreasing the danger of periodic starvation. Cooking also enabled them to add some for...
-
Telescope - astronomy.
Observatory). In some telescopes designed in the 1990s, the mirror’s weight has been dramatically reduced by sandwiching a honeycomb pattern of glass ribs between a thin, butrigid, concave mirror and a flat back plate. Engineers have even developed meniscus mirrors—mirrors that are too thin to support their own weight. An adjustableframework supports the meniscus mirror, and servomechanical actuators, controlled by computer, continually adjust the shape of the mirror as it tracks celestial tar...
-
Montréal - geography.
percent), and Eastern Orthodox (2.8 percent) religions. Another 5.4 percent claim no religious affiliation. IV EDUCATION AND CULTURE Montréal has a large number of private schools, most of them partially funded by the province. Like the rest of Québec province, Montréal has two public schoolsystems, one for French speakers and one for English speakers. The Charter of the French Language (1977), known as Bill 101, restricts access to English-languageschools and requires children of immigrants t...
-
Montréal - Geography.
percent), and Eastern Orthodox (2.8 percent) religions. Another 5.4 percent claim no religious affiliation. IV EDUCATION AND CULTURE Montréal has a large number of private schools, most of them partially funded by the province. Like the rest of Québec province, Montréal has two public schoolsystems, one for French speakers and one for English speakers. The Charter of the French Language (1977), known as Bill 101, restricts access to English-languageschools and requires children of immigrants t...
-
Iranian Art and Architecture
I
INTRODUCTION
Iranian Art and Architecture, the visual arts of Iran.
The first great development of ancient Persian architecture took place under the Achaemenid dynasty during the Persian Empire, from about 550 to 330 BC. Remains of Achaemenian architecture are numerous, the earliest being ruins at Pasargadae, the capital city of Cyrus the Great. These ruins include two palaces, a sacred precinct, acitadel, a tower, and the tomb of Cyrus. The palaces were set in walled gardens and contained central columnar halls, the largest of which was 37 m (111 ft) in length...
-
Volcano.
before eruption. Very violent explosive eruptions are called Plinian eruptions, after Roman naturalist Pliny the Elder. These eruptions can last for several hours to daysand eject a large amount of pyroclastic material. Some volcanoes can produce much more energetic eruptions that eject materials farther from the vents because oftheir andesitic and dacitic composition. Andesitic and dacitic lava is generally thicker than basaltic lava. Stiff lava generally produces more-explosive eruptions. B No...
-
United Arab Emirates - country.
III PEOPLE Most people living in the UAE (known as Emiris) are Arabs, a large majority of whom are city and town dwellers. A small number are nomadic (having no permanent home). The population has grown dramatically since the mid-1960s, largely due to the influx of oil workers to the country. Four-fifths of the UAE’s inhabitants areforeign workers and their families. The UAE also has a very youthful population, due to the large numbers of young foreign workers, a cultural preference for larg...
-
Sudan - country.
B Principal Cities and Political Divisions The principal city is Khartoum, the capital; other major cities include Omdurman and Khartoum North, major industrial centers, and Port Sudan, a seaport on the RedSea. Sudan is divided into 26 states. C Religion and Language About 70 percent of the people of Sudan are Muslims, some 15 percent are Christians, and most of the remainder follow traditional religions. The people of northernSudan are predominantly Sunni Muslims (Sunni Islam). Most of the pe...
-
-
Flower - biology.
insects. The sepals unfurl as the flower opens and often resemble small green leaves at the flower’s base. In some flowers, the sepals are colorful and work with thepetals to attract pollinators. E Variations in Structure Like virtually all forms in nature, flowers display many variations in their structure. Most flowers have all four whorls—pistil, stamens, petals, and sepals. Botanists callthese complete flowers. But some flowers are incomplete, meaning they lack one or more whorls. Incomplet...
-
St. Louis (city) - geography.
I
INTRODUCTION
St. Louis (city) or Saint Louis,
Between 1940 and 1990 the black population in metropolitan St. Louis nearly tripled. Blacks are most heavily concentrated in three areas in the St. Louis metropolitanregion: East Saint Louis, the North Side close to downtown, and an east-west belt extending from the waterfront to beyond Forest Park. In the 19th and early 20th centuries, areas to the north and south of the central business district were settled by immigrant working families from Germany, Ireland,and many Eastern European countrie...
-
Radio.
signal, such as a musical note. This form of modulation, AM, is used in many radiotelephony services including standard radiobroadcasts. AM is also employed for carriercurrent telephony, in which the modulated carrier is transmitted by wire, and in the transmission of still pictures by wire or radio. See Broadcasting, Radio and Television. In FM the frequency of the carrier wave is varied within a fixed range at a rate corresponding to the frequency of a sound signal. This form of modulation, p...
-
North Korea - country.
IV EDUCATION AND CULTURAL ACTIVITY Education and culture in North Korea are under state control and are utilized by the governing Korean Workers’ Party regime to indoctrinate and foster its ideology. A Education Education is free and compulsory in North Korea for the first ten years of schooling. In the late 1980s, some 1.5 million pupils were enrolled annually in elementaryschools, and another 2.8 million students attended vocational and secondary schools. Statistics for subsequent years are...
-
Ecuador - country.
F Natural Resources Ecuador’s main mineral wealth is in petroleum. Other mineral resources of the country include gold, silver, copper, lead, and zinc. Forests cover 38.3 percent of thecountry. G Plants and Animals Along the northern part of the Ecuador coast, and within the inner portion of the southern coast, tropical jungles abound. In some places the jungles extend up theslopes of the Andes as wet, mossy forests. Dense forests cover both flanks of the Cordilleras, as well as the Oriente, u...
-
Cambodia - country.
The population of Cambodia is 14,241,640 (2008 estimate). Population growth per year is estimated at 1.8 percent, one of the highest rates in Asia. The rate of infantmortality is also high. The population density is 81 persons per sq km (209 per sq mi), with the densest concentrations on the heavily cultivated central plain. Themountainous regions of the country, where malaria is widespread, are thinly populated, as are the poorly watered northern provinces. During the late 1970s, under thebruta...
-
Ottawa (city, Ontario) - geography.
National Gallery of Canada, OttawaThe National Gallery of Canada, in Ottawa, houses the foremost collection of Canadian art. Made of glass and granite, it was designedby Canadian-trained architect Moshe Safdie.Wolfgang Kaehler The National Gallery of Canada, designed by Israeli-born, Canadian-trained architect Moshe Safdie, is one of 29 museums in Ottawa. It houses the world’s largest collectionof Canadian art. Across the Ottawa River in Hull is the Canadian Museum of Civilization, which has ext...
-
Jakarta - geography.
than half the households use piped water for drinking. Fewer still use piped water for bathing and washing. Only a small part of Jakarta is served by piped sewers and manyhomes lack septic tanks. III ECONOMY Jakarta developed as a center of trade under the Europeans and it continues to play an important role in international and domestic commerce. The metropolitan region isIndonesia's largest economic center; it attracts most of Indonesia's domestic and foreign investment and, as the administr...
-
-
Manila - geography.
Manila played an important role in trade as a port for the Manila galleons, huge trading ships that carried goods from Manila to Acapulco, Mexico (then part of NewSpain). During this time, Chinese merchants settled in Manila and became middlemen for other trade from China. By the 1590s the Chinese had become aneconomically important community. Many Chinese, aware of the political and social advantages enjoyed by the Roman Catholics in the colony, converted to Catholicismand married Filipino wome...
-
Beijing - geography.
Shoe Factory in BeijingWorkers assemble shoes at a state-owned factory in Beijing, where rapid industrial development has extended into the city’s outlyingareas in recent years. Beijing is China’s second largest industrial center, after Shanghai.Goh Chaihin/AFP As the nation’s capital and political center, the particular economic role of Beijing has been a topic of considerable debate and controversy. The Communist government hasdesignated Beijing as an appropriate center for industrial, commerc...
-
Indianapolis - geography.
nation to handle multiple railroad lines (thus the name “union”). Ringing the Mile Square are a number of historic districts such as Woodruff Place and Lockerbie Square. To the immediate northwest of downtown is Indiana Avenue, thehistoric center of the city’s black population. Some 6 km (4 mi) due north of Monument Circle is the North Meridian Street Historic District, a stretch of mansions built in the1920s and 1930s, including the Governor’s Residence. The district ends at the Central Canal,...
-
San Antonio (city, Texas) - geography.
(1959), St. Mary's University of San Antonio (1852), Our Lady of the Lake University of San Antonio (1895), University of the Incarnate Word (1881), and Trinity University(1869). A leading cultural attraction is the San Antonio Museum of Art. Housed in a renovated historic brewery from the late 19th century, the museum focuses particular attentionon art of the Americas, from pre-Columbian to contemporary works. The Marion Koogler McNay Art Museum displays works by some of the finest painters of...
-
Rome (Italy) - geography.
of Etruscan and Roman art and is located in the mid-16th-century country house of Pope Julius III, and the Borghese Gallery, a museum of paintings and sculpture housedin an early 17th-century palace. The National Roman Museum, designed by Michelangelo, features exhibits of Greek and Roman sculpture, including the Ludovisi Collectionof antiquities. Important collections of art and decorative pieces can also be seen in some of the city’s other palaces. Among these are the Farnese Palace, built bet...
-
Buenos Aires (city) - geography.
Casa Rosada, Buenos AiresThe Casa Rosada (Pink House) is Argentina’s presidential palace, containing the offices of the president. Located on the Plaza de Mayoin downtown Buenos Aires, the palace also contains a museum that is open to the public.Eduardo Gill/Black Star/PNI The Plaza de Mayo, situated close to the waterfront at the eastern edge of Buenos Aires, was the starting point for the original settlement. As the city expanded outward in asemicircle, the plaza continued to serve as the prin...
-
Pyramids (Egypt) - history.
out, to the king’s burial chamber, which ideally was located directly underneath the pyramid’s center point. Sometimes, in addition to the burial chamber, there werestorage chambers within the pyramid. These chambers held objects used in burial rituals as well as items for the deceased to use in the afterlife. Some of these items werevaluable, and in later years people robbed many of the pyramids and stole the objects. Pyramid of Khafre at GizaThe pyramids at Giza in Egypt are among the best-kno...
-
Jerusalem - geography.
There are many other artifacts in the city, tied to various periods of history; those of Canaanite, Israelite, Greek, Roman, Arab, Crusader, and Ottoman origin areamong the more prominent. Modern attractions include the Israel Museum (completed in 1965), which houses the Shrine of the Book, where the Dead Sea Scrolls areexhibited; the Rockefeller Museum (opened in 1938), which contains archaeological finds; the Yad Vashem Holocaust Museum; the Museum of Biblical Archaeology; theMuseum of Islamic...
-
-
Montréal - geography.
requires children of immigrants to be educated in French. As a result, French-language schools became increasingly multiethnic. With four universities, Montréal is one of the leading centers of higher education in Canada. There are two English-language institutions: McGill University (1821) andConcordia University (1974). Their French-language counterparts are the Université de Montréal (1876) and the University of Québec at Montréal (1969). Both private andstate universities are funded by the p...
-
Montréal - geography.
Place Jacques-Cartier, MontréalPlace Jacques-Cartier is named for the French explorer who was one of the first Europeans to venture into Canada in the 16thcentury. It is a popular spot in the city of Montréal, Québec’s largest city.R.E. Murowchick/Photo Researchers, Inc. French influence lasted for a time after the British conquest of 1760, as shown by some late 18th-century houses. British influence came to prevail, however, and most ofOld Montréal is in fact a Victorian Style city, probably th...
-
champ magnétique
By agreement, we call « north magnetic pole » the place where goes out the magnetic field and « south magnetic pole » the place where enters the magnetic field. Scientists found that the magnetic field enters in the north hemisphere and goes out in the south hemisphere. So, the north magnetic pole located in Canada is actually the south magnetic pole. However, because he is situated near the geographic north, we call it North Pole magnetic. Evolution of the Earth's magnetic field : Since the sev...
-
Chromosome.
chromosome breaks off and attaches to another chromosome. A translocation involving chromosomes 9 and 22 is linked to a type of leukemia called chronic myelogenicleukemia. On the sex chromosomes, problems arise in men when an abnormal gene is present on the X chromosome. With no healthy gene found on the Y chromosometo override the abnormal gene, disease may result. For example, men who inherit a mutated gene that causes hemophilia from their mother on the X chromosome willdevelop this bleeding...
-
Nova Scotia - Geography.
summer. Nova Scotia receives an average of more than 1,140 mm (45 in) of rain annually, with the Atlantic shore receiving 1,400 mm (55 in) or more. Most of the provincereceives about 1,900 mm (about 70 in) of snow, and considerable winter precipitation comes in the form of rain or ice storms. The average temperature in January, thecoldest month, is generally about -4°C (about 25°F) near the coast and somewhat colder toward the interior. The average temperature in July, the hottest month, isabout...
-
Nova Scotia - Canadian History.
summer. Nova Scotia receives an average of more than 1,140 mm (45 in) of rain annually, with the Atlantic shore receiving 1,400 mm (55 in) or more. Most of the provincereceives about 1,900 mm (about 70 in) of snow, and considerable winter precipitation comes in the form of rain or ice storms. The average temperature in January, thecoldest month, is generally about -4°C (about 25°F) near the coast and somewhat colder toward the interior. The average temperature in July, the hottest month, isabout...
-
Jacksonville (Florida) - geography.
and southern sections and avoiding the downtown bottleneck where Interstate 95 crosses the Saint Johns River at the Fuller Warren Bridge. In addition to being a regional highway crossroads, the city is a railway hub, with Amtrak passenger service and several freight routes. The city’s expanding airport,located in northern Jacksonville, was the nation’s fastest growing in passenger volume in the mid-1990s. V GOVERNMENT Jacksonville has a mayor-council form of municipal government. The mayor and...
-
Eritrea - country.
1993 decree set up a formal transitional government under EPLF control. This provided for a National Assembly, a president, and council of ministers. Isaias Afwerki,secretary general of the EPLF, was formally elected president by the National Assembly in June 1993. A new constitution was approved in 1997. Under this constitution, the National Assembly is the country’s legislature. Its members are popularly elected to five-yearterms. A president, elected by the National Assembly to a five-year te...
-
-
Central African Republic - country.
Manufacturing activity in the Central African Republic is very limited. Products include cottonseed, peanut, and sesame oils; textiles; leather goods; tobacco products;soap; flour; bricks; and paint. The output of electricity in 2003 was 106 million kilowatt-hours, 80.19 percent of which was generated in hydroelectric installations. Gemdiamonds account for nearly all the country’s mineral output and two-thirds of its export revenue. Production was 250,000 carats in 2004. Uranium was discovered i...
-
Mount Everest - geography.
endangered or killed when their tents collapsed or were ripped to shreds by the gales. Hypothermia, the dramatic loss of body heat, is also a major and debilitatingproblem in this region of high winds and low temperatures. Another hazard facing Everest climbers is the famous Khumbu icefall, which is located not far above Base Camp and is caused by the rapid movement of the Khumbuglacier over the steep rock underneath. The movement breaks the ice into sérac (large, pointed masses of ice) cliffs...
-
Laser.
their atoms into laser light. Consequently, they are the most powerful continuous wave (CW) lasers—that is, lasers that emit light continuously rather than in pulses. C Liquid Lasers The most common liquid laser media are inorganic dyes contained in glass vessels. They are pumped by intense flash lamps in a pulse mode or by a separate gas laserin the continuous wave mode. Some dye lasers are tunable, meaning that the color of the laser light they emit can be adjusted with the help of a prism lo...
-
Canadian Pacific Railway - Canadian History.
roads constructed inland from the lakeshore. However, this changed with the outbreak in Saskatchewan of the Northwest Rebellion by Louis Riel and his supportersagainst the authority of the Canadian government in March 1885. Despite the fact that the railway was not completed, a contingent of troops was able to reachWinnipeg from Montréal in only seven days, much faster than they could have gone overland, and get from there to Saskatchewan in time to successfully put down therebellion. This actio...
-
Himalayas - geography.
result of deforestation the habitat of most of the wildlife has been destroyed. They are now restricted to special protected areas such as the Jaldapara and Kazirangasanctuaries in India ( see Kaziranga National Park) and the Chitawan preserve in Nepal. There are few animals in the Middle Himalayas because of extensive deforestation. In the Great Himalayas musk deer, wild goats, sheep, wolves, and snow leopards are found. The existence of the Abominable Snowman or Yeti has beenreported by highla...
-
Digestive System.
The stomach, located in the upper abdomen just below the diaphragm, is a saclike structure with strong, muscular walls. The stomach can expand significantly to storeall the food from a meal for both mechanical and chemical processing. The stomach contracts about three times per minute, churning the food and mixing it with gastricjuice. This fluid, secreted by thousands of gastric glands in the lining of the stomach, consists of water, hydrochloric acid, an enzyme called pepsin, and mucin (the...
-
Rhode Island - geography.
C (73° F). Along the northern state line, the January mean temperature is about 1° C (about 2° F) colder than in Warwick in January. Along the ocean coast, theJanuary mean temperature is -1° C (30° F). Warm season temperatures are also influenced by the ocean and bay, so temperatures are usually cooler along the coastthan in the interior. The difference tends to be greatest in spring and early summer. Winter temperatures in Rhode Island are usually above -7° C (20° F), buttemperatures colder by...
-
Rhode Island - USA History.
C (73° F). Along the northern state line, the January mean temperature is about 1° C (about 2° F) colder than in Warwick in January. Along the ocean coast, theJanuary mean temperature is -1° C (30° F). Warm season temperatures are also influenced by the ocean and bay, so temperatures are usually cooler along the coastthan in the interior. The difference tends to be greatest in spring and early summer. Winter temperatures in Rhode Island are usually above -7° C (20° F), buttemperatures colder by...
-
-
Kiribati - country.
mainly from Japan, the European Union (EU), and Australia. Kiribati’s only major exports are copra (dried coconut meat), cultivated seaweed, and fish. The United States, Australia, and New Zealand are the leading purchasers ofthe country’s exports. Despite the cultivation of crops for local consumption, Kiribati is heavily dependent upon imported foods. Other imports include machinery andequipment, manufactured goods, and imported fossil fuels, which supply most of the country’s energy. Australi...
-
Barbados - country.
Barbados is served by a public library system centered in Bridgetown. B Culture The culture of Barbados combines English institutions, which evolved through more than three centuries of English rule, with a folk culture of African origin. Because ofits English traditions, Barbados is sometimes called “Little England.” Cricket has traditionally been the national game, and the island has produced some of the sport’sgreatest players. Water sports including surfing, swimming, snorkeling, and sailin...
-
Fossil Fuels.
water molecules. This crystalline solid is known as gas hydrate. Because technology for the commercial extraction of gas hydrates has not yet been developed, this typeof fossil fuel is not included in most world energy resource estimates. However, in February 2007 the U.S. Department of Energy completed the drilling of a well toretrieve core samples of gas hydrates found in the Prudhoe Bay region of Alaska’s North Slope. By identifying the nature of these gas hydrates, the Energy Departmenthoped...
-
Northwest Territories - Geography.
million years ago by the severe bending (folding) and faulting (breaking) of sedimentary rock that was once part of the Interior Plains. During the Wisconsin Ice Age,alpine glaciers covered the Cordillera, and the movement of the glaciers created razor-sharp peaks and ridges in these mountains. The moving glaciers also createdbroad U-shaped valleys. To the east of the Interior Plains, the ancient rocks of the Canadian Shield are exposed at the Earth’s surface, resulting in a rough, rolling terra...
-
Northwest Territories - Canadian History.
million years ago by the severe bending (folding) and faulting (breaking) of sedimentary rock that was once part of the Interior Plains. During the Wisconsin Ice Age,alpine glaciers covered the Cordillera, and the movement of the glaciers created razor-sharp peaks and ridges in these mountains. The moving glaciers also createdbroad U-shaped valleys. To the east of the Interior Plains, the ancient rocks of the Canadian Shield are exposed at the Earth’s surface, resulting in a rough, rolling terra...
-
Asia - geography.
the Himalayas, the world’s highest mountain system. The Pacific Ocean plate drifted westward, scraping along the Eurasian plate and slipping under its coastal edge. This created the islands of Japan, Taiwan, the Kurils, theRyūky ūs, and the Philippines. Southeast Asia lies at the intersection of the Eurasian, Pacific Ocean, and Indian Ocean plates. Over time the contact between these platescreated the mountain ranges of mainland Southeast Asia. The continued slow movement of the plates causes fr...
-
Asia - history.
the Himalayas, the world’s highest mountain system. The Pacific Ocean plate drifted westward, scraping along the Eurasian plate and slipping under its coastal edge. This created the islands of Japan, Taiwan, the Kurils, theRyūky ūs, and the Philippines. Southeast Asia lies at the intersection of the Eurasian, Pacific Ocean, and Indian Ocean plates. Over time the contact between these platescreated the mountain ranges of mainland Southeast Asia. The continued slow movement of the plates causes fr...
-
Pyramids (Egypt) - geography.
limestone debris left over from the construction work. When the workers had completed the pyramid and installed the pyramidion, or cap stone, ramps still covered the surface of the pyramid. As the workers dismantled the ramps from the top down, they slowly exposed the pyramid’s stone surface, which stonemasons smoothed and polished. When the ramp was gone, the pyramid wasdisplayed in its full majesty. B Interior The interior of the Great Pyramid is complex, with a series of passages leading t...
-
-
Pyramids (Egypt) - History.
limestone debris left over from the construction work. When the workers had completed the pyramid and installed the pyramidion, or cap stone, ramps still covered the surface of the pyramid. As the workers dismantled the ramps from the top down, they slowly exposed the pyramid’s stone surface, which stonemasons smoothed and polished. When the ramp was gone, the pyramid wasdisplayed in its full majesty. B Interior The interior of the Great Pyramid is complex, with a series of passages leading t...
-
Conservation.
cancers, Hodgkin’s disease and leukemia. Unfortunately, human activities have greatly reduced biodiversity around the world. The 20th century encompasses one of the greatest waves of extinction, orelimination of species, to occur on the planet. The greatest threat to biodiversity is loss of habitat as humans develop land for agriculture, grazing livestock, industry,and habitation. The most drastic damage has occurred in the tropical rain forests, which cover less than seven percent of the Earth’...