767 résultats pour "higher"

• Turkey - country.

  has a general elevation of 900 to 1,500 m (3,000 to 5,000 ft) above sea level. The eastern highlands region is the most mountainous and rugged portion of Turkey; Mount Ararat (Ağrı Da ğı) is the highest peak in the country at 5,165 m (16,945ft). Many Christians and Jews believe it to be the same Mount Ararat mentioned in the Bible as the place where Noah’s ark came to rest. The eastern highlands are thesource for both the Tigris (Dicle) and Euphrates (Fir āt)—two of southwestern Asia’s principal...

• Brazil - country.

  occasional droughts. Brazil contains a wealth of mineral and plant resources that have not yet been fully explored. It possesses some of the world’s largest deposits of iron ore and containsrich deposits of many other minerals, including gold and copper. Brazil’s fossil fuel resources are modest, but this limitation is offset by the considerable hydroelectricpotential of the nation’s many rivers. Although Brazil is an important producer of tropical crops, areas of highly fertile land are limited...

• Electricity I INTRODUCTION Electricity, one of the basic forms of energy.

  electrons in the neutral object are attracted to the positive object. Some of these electrons flow to the side of the neutral object that is nearest to the positive object.This side of the neutral object accumulates electrons and becomes negatively charged. Because electrons leave the far side of the neutral object while its protonsremain stationary, that side becomes positively charged. Since the negatively charged side of the neutral object is closest to the positive object, the attraction bet...

• France - country.

  In both the Paris and Aquitaine basins, fertile soils derived from limestone and wind-deposited dust, called loess, have supported prosperous agriculture since ancienttimes. Other lowlands in France are scattered and relatively small. They include the Alsace Plain in the east, bordering Germany, the valley of the Rhône River in thesoutheast, and the Languedoc Plain along the Mediterranean coast. A2 Uplands France contains several regions of uplands, the worn down remains of ancient mountain sys...

• Cuba - country.

  Only two land mammals, the hutia, or cane rat, and the solenodon, a rare insectivore that resembles a rat, are known to be indigenous. The island has numerous batsand nearly 300 kinds of birds, including vultures, wild turkeys, quail, finches, gulls, macaws, parakeets, and hummingbirds. The bee hummingbird of Cuba is thesmallest bird in the world. Among the few reptiles are tortoises, caimans, the Cuban crocodile, and a species of boa that can attain a length of 3.7 m (12 ft). More than700 speci...

• Michigan - geography.

  The interior location of Michigan in the northern part of North America results in a continental climate, characterized by four definite seasons with moist, mild to hotsummers and snowy, cold winters. Winds off of Lakes Michigan and Superior in winter create heavy snow accumulations in nearby areas. The tempering effects of LakeMichigan account for the presence of the state’s famous fruit-growing belt along the lake’s shore. Since the water is colder than the land in spring, the westerly windspa...

• Michigan - USA History.

  The interior location of Michigan in the northern part of North America results in a continental climate, characterized by four definite seasons with moist, mild to hotsummers and snowy, cold winters. Winds off of Lakes Michigan and Superior in winter create heavy snow accumulations in nearby areas. The tempering effects of LakeMichigan account for the presence of the state’s famous fruit-growing belt along the lake’s shore. Since the water is colder than the land in spring, the westerly windspa...

• Light - astronomy.

  Each different frequency or wavelength of visible light causes our eye to see a slightly different color. The longest wavelength we can see is deep red at about 700 nm.The shortest wavelength humans can detect is deep blue or violet at about 400 nm. Most light sources do not radiate monochromatic light. What we call white light,such as light from the Sun, is a mixture of all the colors in the visible spectrum, with some represented more strongly than others. Human eyes respond best to greenlight...

• Thailand - country.

  E Natural Resources Thailand possesses a range of mineral resources. Tin is mined in the peninsula. Important gemstones, such as sapphires, are found in the southeast, and coal reserves,particularly lignite, are in the north. Fish are abundant in rivers and coastal waters. In addition to being consumed domestically, fish are also exported. F Climate Thailand experiences a typical monsoon climate. Winds blow from the northeast during the winter months of October to March or April (known as the...

• Roman Empire .

  A Government Augustus did not derive his power from any single office, but from the authority of his name and his victory. In fact, he carefully pieced together a patchwork of powersthat allowed him to be an absolute ruler and yet avoid the hatred Caesar aroused as dictator. In Latin, the name Augustus implies both political authority and religiousrespect. The Romans had for some time called Octavian imperator , a title once awarded to victorious generals that soon became associated with the r...

• Roman Empire - History.

  A Government Augustus did not derive his power from any single office, but from the authority of his name and his victory. In fact, he carefully pieced together a patchwork of powersthat allowed him to be an absolute ruler and yet avoid the hatred Caesar aroused as dictator. In Latin, the name Augustus implies both political authority and religiousrespect. The Romans had for some time called Octavian imperator , a title once awarded to victorious generals that soon became associated with the r...

• Québec - Geography.

  facilities. Tributaries south of the St. Lawrence include the Richelieu, the Saint-François, and the Chaudière rivers, which are only a few hundred kilometers long. TheRimouski and Matane rivers, also south of the St. Lawrence, are popular areas for recreation and salmon fishing. In the Canadian Shield, the longest rivers are theRupert, Eastmain, Grande Baleine, and La Grand-Rivière, which is the site of a huge hydroelectric complex. C Coastlines Québec has two systems of saltwater coastline. O...

• Québec - Canadian History.

  facilities. Tributaries south of the St. Lawrence include the Richelieu, the Saint-François, and the Chaudière rivers, which are only a few hundred kilometers long. TheRimouski and Matane rivers, also south of the St. Lawrence, are popular areas for recreation and salmon fishing. In the Canadian Shield, the longest rivers are theRupert, Eastmain, Grande Baleine, and La Grand-Rivière, which is the site of a huge hydroelectric complex. C Coastlines Québec has two systems of saltwater coastline. O...

• Chile - country.

  D Plant and Animal Life The indigenous plant life of Chile varies according to climatic zone. Plant life in the northern region includes brambles and cactus and has little variety. Here, theAtacama provides one of the best examples on Earth of an absolute desert. The more humid Central Valley supports several species of cacti, espino (a thorny shrub),grasses, and the Chilean pine, which bears edible nuts. Dense rain forests are located south of Valdivia with laurel, magnolia, false beech, and v...

• Argentina - country.

  Patagonia lies in the rain shadow of the Andes and so receives little moisture. As a result it is used primarily for grazing sheep, although some crops are grown on smallfarms in irrigated valleys. Several major oil fields also are in Patagonia. At the southern tip of Patagonia is Tierra del Fuego, a large mountainous island shared byArgentina and Chile. B Rivers and Lakes Most of Argentina’s rivers empty into the Atlantic Ocean. Three rivers—the Paraná, Paraguay, and Uruguay—flow generally sou...

• 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...

• Coronary Heart Disease.

  when a patient is at rest may indicate that the blood supply of the heart is not normal, and the ECG can often detect damage from a previous heart attack. In anexercise stress test, an ECG is recorded while a patient is performing physical activity such as walking on a treadmill or riding a stationary bicycle. As the intensity ofexercise increases, the doctor looks for specific changes in the ECG that indicate the heart is not getting enough oxygen. In cardiac catheterization, a long, thin, flex...

• Hungary - country.

  Northern Hungary lacks sufficient water, especially between July and October, when precipitation levels are typically low. Canals irrigate the Great Hungarian Plain,which is subject to drought. Because of the country’s mainly flat terrain, only limited water resources can be harnessed for hydroelectric power. F Environmental Issues Rapid industrialization in Hungary following World War II contributed significantly to a number of major environmental problems, including air, water, and soil pollu...

• Alabama (state) - geography.

  indentations along the coast are measured, the state’s shoreline is 977 km (607 mi) long. It includes the shores of Mobile Bay, an inlet 56 km (35 mi) long at the mouthof the Mobile River. Barrier beaches partly block the entrance to the bay, leaving narrow openings on either side of Dauphin Island. Dauphin and other islands alongAlabama’s coast west of Mobile Bay are separated from the mainland by Mississippi Sound. D Climate Alabama has a humid subtropical climate, with short, relatively mild...

• Alabama (state) - USA History.

  indentations along the coast are measured, the state’s shoreline is 977 km (607 mi) long. It includes the shores of Mobile Bay, an inlet 56 km (35 mi) long at the mouthof the Mobile River. Barrier beaches partly block the entrance to the bay, leaving narrow openings on either side of Dauphin Island. Dauphin and other islands alongAlabama’s coast west of Mobile Bay are separated from the mainland by Mississippi Sound. D Climate Alabama has a humid subtropical climate, with short, relatively mild...

• Temple (building) I INTRODUCTION Wat Phra Kaeo Thailand has nearly 18,000 Buddhist temples, called wats, throughout the country.

  colonnaded terraces connected by ramps. The surrounding area was planted with trees and flowers during Hatshepsut’sreign and for many years after.Gian Berto Vanni/Art Resource, NY In ancient Egypt, temples were grandiose, built of huge blocks and columns of stone. Often they were enlarged by successive rulers to form strung-out series of templeparts, as in the gigantic Temple of Amon (circa 1550-1070 BC) at Al Karnak. The Nile cliffs were used as settings for temples, such as the massive mortuar...

• Toronto - geography.

  now a museum. In the far northeast side of the City is the Toronto Zoo, a modern zoo covering many acres and with well-designed animal displays. Originally known as the SkyDome, the Rogers Centre is a state-of-the-art stadium complex that opened in 1989. The stadium features a retractable roof that can openin 20 minutes to expose the playing field and most of the 50,000 seats to the open air. It is the home of the Toronto Argonauts of the Canadian Football League and theToronto Blue Jays of Majo...

• Toronto - Geography.

  now a museum. In the far northeast side of the City is the Toronto Zoo, a modern zoo covering many acres and with well-designed animal displays. Originally known as the SkyDome, the Rogers Centre is a state-of-the-art stadium complex that opened in 1989. The stadium features a retractable roof that can openin 20 minutes to expose the playing field and most of the 50,000 seats to the open air. It is the home of the Toronto Argonauts of the Canadian Football League and theToronto Blue Jays of Majo...

• Serbia - country.

  Minority groups speak their own languages, such as Albanian and Hungarian. Bosniaks generally speak Bosnian and write it with the Latin alphabet. Serbs are by tradition Orthodox Christians. The Roman Catholic and Protestant churches also have adherents in Serbia. Most of the ethnic Albanians of Kosovo areSunni Muslims ( see Sunni Islam), as are the Bosniaks of the Sandžak region. Bosniaks are descendants of Slavs who converted to Islam in the 15th and 16th centuries. B Education The leading in...

• Electric Motors and Generators.

  the armature. It is often desirable to generate as high a voltage as possible, and rotating armatures are not practical in such applications because of the possibility of sparkingbetween brushes and slip rings and the danger of mechanical failures that might cause short circuits. Alternators are therefore constructed with a stationary armaturewithin which revolves a rotor composed of a number of field magnets. The principle of operation is exactly the same as that of the AC generator described,...

• Population.

  year AD 1, and it took more than 1,500 years to reach the 500 million mark. Growth was not steady but was marked by oscillations dictated by climate, food supply, disease, and war. Starting in the 17th century, great advances in scientific knowledge, agriculture, industry, medicine, and social organization made possible rapid acceleration inpopulation growth. Machines gradually replaced human and animal labor. People slowly acquired the knowledge and means to control disease. By 1900 the worldp...

• Stress (psychology).

  blood flow is diverted from the internal organs and skin to the brain and muscles. Breathing speeds up, the pupils dilate, and perspiration increases. This reaction issometimes called the fight-or-flight response because it energizes the body to either confront or flee from a threat. Another part of the stress response involves the hypothalamus and the pituitary gland, parts of the brain that are important in regulating hormones and many otherbodily functions. In times of stress, the hypothal...

• Bhutan - country.

  languages ( see Indo-Iranian Languages) and follow Hinduism. Nepalese people constitute a significant portion of Bhutan’s population. They are the most recent settlers, occupying south central and southwestern Bhutan. TheNepalese are mainly Rai, Gurung, and Limbu ethnic groups from the eastern mountains of Nepal. Nepalese immigration has been banned since 1959, when theBhutanese government feared the minority would become too populous. Nepalese are not permitted to live in the central Middle Hi...

• Arctic - Geography.

  The Arctic is not a frozen desert devoid of life on land or sea, even during the cold, dark winter months. Spring brings a phenomenal resurgence of plant and animal life.Low temperatures are not always the critical element—moisture, the type of soil, and available solar energy are also extremely important. Some animals adapt well toArctic conditions; for instance, a number of species of mammals and birds carry additional insulation, such as fat, in cold months. Arctic summers with extended dayli...

• Lithuania - country.

  pollution. III PEOPLE Ethnic Lithuanians constitute about 80 percent of the country’s population. The proportion of Lithuanians increased slightly in the first years after the dissolution of theSoviet Union—many Lithuanians returned to their homeland from that country and abroad while some Russians, Ukrainians, and Belarusians left the country. Russiansand Poles constitute the country’s largest minority groups, each accounting for roughly 7 percent of the population. Jews were the largest mino...

• Optics I INTRODUCTION Mirage Mirages appear because differences in air temperature cause light rays from an object to take different paths to a viewer's eye.

  Refraction of Light by DiamondsThe brilliance of diamonds is due to their high refractive index, a measure of how strongly a transparent material bendslight rays. The skill of the gem-cutter lies in angling the facets of the stone so that each light ray entering it is reflectedmany times before it emerges again.Spencer Grant/Photo Researchers, Inc. The amount of light reflected depends on the ratio of the refractive indexes for the two media. The plane of incidence contains the incident ray and...

• Bolivia - country.

  E Plants and Animals Because of the wide variations in elevation, plant and animal species of nearly every climatic zone are found in Bolivia. A coarse grass, called ichu, grows on the largelybarren high plateau in the west. Para rubber trees, more than 2,000 species of hardwood trees, and vanilla, sarsaparilla, and saffron plants are common in the tropicalforests of the east. The llama, found chiefly on the Altiplano, is an efficient beast of burden. Alpacas and vicuñas also inhabit the platea...

• Andes - geography.

  The most important native domestic animal of the Andes is the llama, a member of the same family as the camel. The llama, found predominantly in Peru and Bolivia, canlive at high altitudes. It is used as a beast of burden and yields wool, milk, and meat. The alpaca, an animal related to the llama, is raised for its wool. Wild animals includethe vicuña, which is another member of the camel family, and the chinchilla, which is a member of the rodent family. Both the vicuna and the chinchilla are p...

• South America - geography.

  B Natural Regions Tierra del Fuego, ArgentinaUshuaia, on Argentina’s island of Tierra del Fuego, is the world’s southernmost city. Argentina claims part of the Tierra del Fuegoarchipelago, including the largest island, known as Tierra del Fuego or Great Island, and Staten Island. Chile claims the remainder ofthe islands in the territory.R. Van Nostrand/Photo Researchers, Inc. Rising abruptly from the northwestern and western coasts of the continent are the Andes. They consist of a single chain...

• Atlanta - geography.

  Prominent cultural and historical institutions in the city include the High Museum of Art (1983), designed by the noted postmodern American architect Richard Meier; theAtlanta Symphony; the Atlanta History Center, which maintains a history museum, historic houses and gardens, and extensive library and archives; NexusContemporary Art Center; the Robert W. Woodruff Arts Center; the Apex Museum; the Michael C. Carlos Museum at Emory University; the Clark Atlanta University ArtGallery; Fernbank Scie...

• Gemstones.

  In the late 1960s a method was developed for “growing” diamonds by heating a diamond particle to a high temperature and subjecting it to methane gas. The gasdecomposes into carbon atoms, which adhere to the diamond crystal. The crystal structure of the enlarged diamond is identical to that of a natural diamond. Diamondsof about 1 carat (200 mg or 0.007 oz) have been produced by this method, but their cost is still considerably higher than that of naturally occurring diamonds. Sapphires are made...

• Jimmy Carter.

  B Election of 1976 Carter apparently decided as early as 1972, halfway through his four-year term as governor, that he would seek the presidency of the United States. Soon after the1972 election, his campaign manager drew up a detailed campaign strategy. Carter followed the plan closely, beginning an exhausting schedule of campaigning as soonas his gubernatorial term ended. When Carter formally announced in January 1975 that he was a candidate for president, he had almost no national reputation...

• Jimmy Carter

  B Election of 1976 Carter apparently decided as early as 1972, halfway through his four-year term as governor, that he would seek the presidency of the United States. Soon after the1972 election, his campaign manager drew up a detailed campaign strategy. Carter followed the plan closely, beginning an exhausting schedule of campaigning as soonas his gubernatorial term ended. When Carter formally announced in January 1975 that he was a candidate for president, he had almost no national reputation...

• James Polk.

  1824. Jackson had won a plurality of the popular and electoral votes. But because he lacked a majority of the electoral votes, the House of Representatives had todecide the election among the three candidates with the highest number of electoral votes. When Henry Clay, the candidate who had come in fourth, swung his supportto Adams, Adams won the election. Polk, with his firm belief in democratic rule, held that the election of Adams was a violation of the people's will. In his first speech befo...

• James Polk

  1824. Jackson had won a plurality of the popular and electoral votes. But because he lacked a majority of the electoral votes, the House of Representatives had todecide the election among the three candidates with the highest number of electoral votes. When Henry Clay, the candidate who had come in fourth, swung his supportto Adams, Adams won the election. Polk, with his firm belief in democratic rule, held that the election of Adams was a violation of the people's will. In his first speech befo...

• Czech Republic - country.

  enforcement of environmental regulations. Environmental considerations have also led some government officials to promote nuclear energy as a key source of powerfor the country’s future. The Czech Republic produces most of its energy by burning domestic coal. Much of the coal burned is low quality with a high ash and sulfur content—a key componentof acid rain—producing high levels of air pollution. Forests in the Czech Republic are among the most seriously affected by acid rain in all of Europe....

• Bear - biology.

  programs sponsored by zoos or other breeding centers have attempted to breed giant pandas in captivity, although most of these programs have proved unsuccessful.Among the difficulties faced by captive breeders has been the problem of encouraging a female giant panda to mate with a selected male during the two to three daysof the year when she is most fertile, a period known as estrus. B Spectacled Bear Creamy-white rings surrounding the eyes give the spectacled bear its name. Its shaggy coat of...

• Native American Art.

  folding, braiding or weaving, could also be sewn onto the hide. The production of decorated clothing and bags increased after contact with Europeans as a greater variety of textiles and other materials became available throughtrade. Imported glass beads inspired native women, who quickly adapted quillwork techniques for the creation of beaded apparel. European curvilinear and floraldesigns of the 19th century proved as meaningful for the native women who worked with them as they were for the non...

• Cellular Radio Telephone.

  There were more than 120 million wireless subscribers in the United States in 2001, according to the Cellular Telecommunications and Internet Association, with thenumber of new users increasing significantly each year. Forecasters and regulators did not anticipate this growth, however. Network equipment and start-up costs weresubstantial, and the cost to consumers was high. Providers had limited their networks to a small group of high-volume business users. Eventually, the providersrecognized th...

• Aerospace Medicine - astronomy.

  medically as aeroembolism and popularly as the bends, leads to confusion, paralysis, or neurocirculatory collapse. The most characteristic symptoms of the bends arepain in the large joints resulting from pressure of the gas on tendons and nerves, together with spasm of the blood vessels. Preflight inhalation of pure oxygen toeliminate nitrogen from the system has proved valuable as a preventive measure. Rapid decompression, resulting from accidental failure at high altitudes of thepressure withi...

• Africa.

  The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...

• 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...

• Meteorology.

  to find the corresponding relative humidity and dew-point temperature. III SPECIAL METEOROLOGICAL INSTRUMENTS Meteorologists have developed several sophisticated instruments that measure multiple physical characteristics of the air simultaneously and at more than one location.The most important of these special instruments are radiosondes, Doppler radar, and weather satellites. A Radiosonde A radiosonde measures air temperature, air pressure, and humidity from the earth’s surface up to an alt...

• Electron I INTRODUCTION Models of the Atom Once scientists discovered the electron, they set out to explain how electrons behave in atoms.

  Electron Density and Orbital ShapesAtomic orbitals are mathematical descriptions of where the electrons in an atom (or molecule) are most likely to be found.These descriptions are obtained by solving an equation known as the Schrödinger equation, which expresses ourknowledge of the atomic world. As the angular momentum and energy of an electron increases, it tends to reside indifferently shaped orbitals. The orbitals corresponding to the three lowest energy states are s, p, and d, respectively....

• World Energy Supply.

  In the 1990s, oil production by non-OPEC countries remained strong and production by OPEC countries rebounded. The result at the end of the 20th century was aworld oil surplus and prices (when adjusted for inflation) that were lower than in 1972. Experts are uncertain about future oil supplies and prices. Low prices have spurred greater oil consumption, and experts question how long world petroleum reservescan keep pace with increased demand. Many of the world’s leading petroleum geologists beli...