683 résultats pour "used"
- Nuclear Chemistry - chemistry.
-
Gold - chemistry.
producers of gold during this period. Spain's domination in South America resulted, in the 16th century, in a large increase in gold produced in the New World; someresulted from simple seizure of gold from the Native Americans, who had long mined the metal. In the same century Mexico contributed about 9 percent of the totalworld production. Gold was discovered in Australia in February 1851, and rich fields were found there. By the middle of the 19th century the United States produced a considera...
- Lithium - chemistry.
-
Windmill.
James F. ManwellMicrosoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
-
White House - geography.
A large complex is needed for the many activities that take place at the White House. The White House has 132 rooms, 4 dining rooms, 35 bathrooms, 8 staircases, 3elevators, a clinic, a dentist’s office, a bowling alley, and a movie theater. About 150 people work in the White House offices, and another 100 people are needed to keepthe White House running. Congress provides funds to each first family to redecorate and refurnish the family quarters according to its wishes. The family quarters of th...
-
Matrix Theory and Linear Algebra
I
INTRODUCTION
Matrix Theory and Linear Algebra, interconnected branches of mathematics that serve as fundamental tools in pure and applied mathematics and are becoming
increasingly important in the physical, biological, and social sciences.
vectors and V is called a vector space of dimension m. Two- and three-dimensional Euclidean spaces are vector spaces when their points are regarded as specified by ordered pairs or triples of real numbers. Matrices may be used to describe linear changes from one vector space into another. Contributed By:James Singer Reviewed By:J. Lennart BerggrenMicrosoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
- aircraft, British
- Aluminum - chemistry.
-
- Mercury Program - astronomy.
- Phosphorus - chemistry.
-
Money.
A Early Monetary Regulations In the American colonies, coins of almost every European country circulated, with the Spanish dollar predominating. Because of the scarcity of coins, the colonists alsoused various primitive mediums of exchange, such as bullets, tobacco, and animal skins. Many of the colonies issued paper money that circulated at varying rates ofdiscount. The first unified currency consisted of the notes issued by the Continental Congress to finance the American Revolution. These no...
- Arsenic - chemistry.
- Gemini Program - astronomy.
- instruction c_51
-
Dinosaurs.
protected their necks. Ankylosaurus was about 33 feet (10 meters) long. ORNITHOPODS Ornithopods were once the most numerous plant-eating dinosaurs. There were many different kinds.Over time, ornithopods developed broad beaks. These later ornithopods are called duck-billed dinosaurs.Some ornithopods were small and ran fast. Others were huge. Iquanodon, for example, was 25 feet (7.5 meters) long. PACHYCEPHALOSAURS These dinosaurs walked on two feet. They had thick, dome-shaped skulls. Scienti...
-
Scandinavian Mythology
I
INTRODUCTION
Scandinavian Mythology, pre-Christian religious beliefs of the Scandinavian people.
Werner Forman/Corbis Many ancient mythological heroes, some of whom may have been derived from real persons, were believed to be descendants of the gods; among them were Sigurdthe Dragon-slayer; Helgi Thrice-Born, Harald Wartooth, Hadding, Starkad, and the Valkyries. The Valkyries, a band of warrior-maidens that included Svava andBrunhild, served Odin as choosers of slain warriors, who were taken to reside in Valhalla. There the warriors would spend their days fighting and nights feasting untilR...
-
- The way in which companies frame themselves, their products and their clients
-
Ernest Hemingway
I
INTRODUCTION
Ernest Hemingway
Twentieth-century American author Ernest Hemingway wrote novels and stories that reflected his rich life experiences as
a war correspondent, outdoor sportsman, and bullfight enthusiast.
In his early work Hemingway used themes of helplessness and defeat, but in the late 1930s his writing began to reflect concerns about social problems. His novel To Have and Have Not (1937) and his play The Fifth Column, published in The Fifth Column and the First Forty-nine Stories (1938), strongly condemned economic and political injustice. Two of his best short stories, “The Short Happy Life of Francis Macomber” and “The Snows of Kilimanjaro,” were part of the story collection. In thecla...
-
Genetics - biology.
construct identical buildings. Just as each contractor would require a full copy of the blueprint to construct a complete building, each new cell needs a complete copy ofan organism’s genetic information to function properly. Organisms use two types of cell division to ensure that DNA is passed down from cell to cell during reproduction. Simple one-celled organisms and other organisms thatreproduce asexually—that is, without the joining of cells from two different organisms—reproduce by a proces...
-
Han Dynasty - history.
of merit rather than birth. Written examinations were adopted as a means of determining the best qualified people, although use of the examinations in actually makingappointments was limited. A school was established at the capital for training government officials. The administrative bureaucracy was systematized, and a career civilservice was created and extended through much of the empire. Although personally interested in the magical side of Daoism, Wudi made a descendent of Confucius the sup...
-
Han Dynasty - history.
of merit rather than birth. Written examinations were adopted as a means of determining the best qualified people, although use of the examinations in actually makingappointments was limited. A school was established at the capital for training government officials. The administrative bureaucracy was systematized, and a career civilservice was created and extended through much of the empire. Although personally interested in the magical side of Daoism, Wudi made a descendent of Confucius the sup...
-
Quiet Revolution - Canadian History.
in social policy, that the federal government currently administered. Since the provincial government would be administering these programs, it argued that it wouldrequire a much larger share of the taxes paid by Québec residents. During the period of the Quiet Revolution, especially after Lester Pearson became prime minister in 1963, the federal government met some of the Québec demands.The federal government allowed Québec to take over its programs of youth allowances and university loans, and...
-
Medicine.
C Other Health Professionals Medicine is not restricted to physicians. A wide variety of health care practitioners work in this exciting field. By far the largest professional group is nurses. Registerednurses help physicians during examinations, treatment, and surgery. They observe, evaluate, and record patients’ symptoms, administer medications, and provideother care ( see Nursing). Nurse practitioners perform basic duties once reserved for physicians, such as diagnosing and treating common i...
-
Titian.
Flaying of Marsyas (circa 1570-76, Kroměříž, Czech Republic) and the Nymph and Shepherd (circa 1574, Kunsthistorisches Museum). Here colors are more subdued, but the turbulence of the brushwork, hardly matched again until 20th-century painting, almost submerges the form entirely. These late mythological paintings, whichTitian called poesie (poems), stand among the most formidable statements ever made of the irresistible, elemental powers of nature. These works are paralleled by a sequence...
-
-
If he asks anything, just let him know that it will be OK.
That's true. It's ashame tobe inside. I guess so. But here weare. I wanted toturn toface him, butIcouldn't. Imoved myhand totouch hishand. They letyou outofschool? Practically immediately. Do you know whathappened? Yeah. Have youheard fromMom orDad? Mom. What didshe say? She said everything wasfineandshewould behome soon. Dad willbehome soon,too.Once hecan close upthe store. Yeah. You pressed yourpalms intothebed likeyou were trying tolift itoff us. Iwanted totell you something, butIdidn't know...
-
Compositionality
sentence construction, an operation on meanings, such that the meaning of any sentence is mechanically determined by applying the operations on meanings (given by the rules used in constructing the sentence) to the meanings of the simple parts. (Often a host of extra restrictions are incorporated. For example: the operations may be limited to applying function to argument; the order in which operations are applied may be settled by the structure of the sentence.) Some see such principles as prov...
-
Skateboarding.
The earliest skateboards first appeared in the 1940s and 1950s. Many of the early boards were toy scooters whose handlebars had been removed. Other homemadeskateboards were steel-wheeled roller skates nailed onto a piece of wood. The first commercially produced skateboards appeared in the early 1960s, when MakahaSkateboards established a successful business. The Makaha company later developed the tail. By the 1970s, skateboard design had advanced, and the models produced were much safer than tho...
- Licence
-
Great White Shark - biology.
The great white shark is a rare species that takes long to reach sexual maturity and that reproduces slowly. Populations cannot easily increase if depleted. The biggestthreat to great whites comes from being unintentionally caught in fishing nets. Some targeted fisheries and sport fishing for great white sharks also occur. Trade ingreat white shark products includes the jaws (which can sell for thousands of dollars as curios), individual teeth, and leather from its skin. Fins from all sharks, in...
-
Acquired Immunodeficiency Syndrome.
child transmission is particularly prevalent in Africa. D Misperceptions About HIV Transmission The routes of HIV transmission are well documented by scientists, but health officials continually grapple with people’s unfounded fears concerning the potential for HIVtransmission by other means. HIV differs from other infectious viruses in that it dies quickly if exposed to the environment. No evidence has linked HIV transmission tocasual contact with an infected person, such as a handshake, huggi...
-
Communism
access to, resources, but the underlying principle is quite similar. Rather than freeing some or even all people in a society to devote themselves to a higher cause, secular communism is designed to allow everyone to pursue personal fulfilment. It may best be characterized by a slogan adopted by Marx that appears to have been first published on the title page of Cabet's Voyage en Icarie (1840): ‘From each according to his ability, to each according to his need' . In other words, each pers...
-
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...
-
-
Roman Art and Architecture - history.
house, records office, and basilica. Imperial Forum, RomeThe Roman Forum was founded at the beginning of the Roman republic (around 500 bc), and it continued to develop into the late 2ndcentury ad. Among the ruins seen here are the Temple of Antoninus and Faustina (since converted into a church, background, left),the foundations of the Basilica Julia (foreground, center), and the three remaining columns of the Temple of Castor and Pollux(background, right).Donadoni/Bruce Coleman, Inc. The basili...
-
Space Exploration - astronomy.
to produce 250,000 newtons (56,000 lb) of thrust. The Germans launched thousands of V-2s carrying explosives against targets in Britain and The Netherlands. Whilethey did not prove to be an effective weapon, V-2s did become the first human-made objects to reach altitudes above 80 km (50 mi)—the height at which outer spaceis considered to begin—before falling back to Earth. The V-2 inaugurated the era of modern rocketry. A2 Early Artificial Satellites During the years following World War II, the...
-
Commentary The adeventures of Huck Finn
same hundrun is emphasized by the use of the modals « would », « could » and the verbal form « used to ». So, this everyday life is depicted by the narrator as « lovely ». The child describes his habits as sacred ones. The way it is depicted seems mechanical : everything has a time to be done and is done by the time the children are allowing it. For instance, they are eating first, then having a nap, then shaving « soon as it was night ». The actions are ennumerated, which emphasize the idea o...
-
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...
- aircraft, Japanese
-
Bridge (game).
IV DUPLICATE BRIDGE Duplicate bridge is a variety of contract bridge in which the element of luck affecting the final score is greatly decreased and the factor of skill is correspondinglyincreased. Duplicate is virtually the only game now played in championship bridge tournaments and matches. Duplicate bridge can be played by any number of players divided into pairs or teams. Each pair competes against all (or in some duplicate tournaments against half) theother pairs. The cards are all dealt...
-
Leonardo da Vinci.
Leonardo's stylistic innovations are even more apparent in The Last Supper, in which he represented a traditional theme in an entirely new way. Instead of showing the 12 apostles as individual figures, he grouped them in dynamic compositional units of three, framing the figure of Christ, who is isolated in the center of the picture.Seated before a pale distant landscape seen through a rectangular opening in the wall, Christ—who has just announced that one of those present will betrayhim—repres...
- Sodium - chemistry.
-
-
Excerpt from Little Dorrit - anthology.
'That,' said the turnkey, 'is agen her.' 'She is so little used to go out alone,' said the debtor, 'that I am at a loss to think how she will ever make her way here, if she walks.' 'P'raps,' quoth the turnkey, 'she'll take a ackney coach.' 'Perhaps.' The irresolute fingers went to the trembling lip. 'I hope she will. She may not think of it.' 'Or p'raps,' said the turnkey, offering his suggestions from the top of his well-worn wooden stool, as he might have offered them to a...
-
Leonardo da Vinci
I
INTRODUCTION
Leonardo da Vinci
Leonardo da Vinci was known not only as a masterful painter but as an architect, sculptor, engineer, and scientist.
and conservation program made use of the latest technology to reverse some of the damage. Although much of the original surface is gone, the majesty of thecomposition and the penetrating characterization of the figures give a fleeting vision of its vanished splendor. The Virgin of the RocksThe Virgin of the Rocks by Leonardo da Vinci was actually painted twice. The first version, done in 1485, wascommissioned to be an altarpiece but was evidently rejected. That painting now hangs in the Louvre,...
-
Thermodynamics
I
INTRODUCTION
Thermodynamics, field of physics that describes and correlates the physical properties of macroscopic systems of matter and energy.
Carnot EngineThe idealized Carnot engine was envisioned by the French physicist Nicolas Léonard Sadi Carnot, who lived during theearly 19th century. The Carnot engine is theoretically perfect, that is, it converts the maximum amount of energy intomechanical work. Carnot showed that the efficiency of any engine depends on the difference between the highest andlowest temperatures reached during one cycle. The greater the difference, the greater the efficiency. An automobileengine, for example, wou...
-
Afghanistan - country.
D Climate Most of Afghanistan has a subarctic mountain climate with dry and cold winters, except for the lowlands, which have arid and semiarid climates. In the mountains and afew of the valleys bordering Pakistan, a fringe effect of the Indian monsoon, coming usually from the southeast, brings moist maritime tropical air in summer.Afghanistan has clearly defined seasons: Summers are hot and winters can be bitterly cold. Summer temperatures as high as 49°C (120°F) have been recorded in thenorth...
-
Chad - country.
B Industries The processing of cotton and cottonseed oil and the manufacturing of peanut oil are major industries in Chad. Modern meatpacking plants have been established inN’Djamena and Sarh. The fishing industry furnishes fresh, dried, and smoked fish for domestic use and export. Petroleum mining and processing are increasinglyimportant industries in Chad. Gold and natron, a mineral used to make soap, glass, paper, and medicines, are also mined. Forestry is important in the south. The outputo...
-
Poetry
I
INTRODUCTION
Phyllis McGinley
American poet and author Phyllis McGinley composed light, witty verse, much of which deals with family life.
repetition of certain lines and the rhyming of certain lines. The Provençal sestina features a set of six words that end lines (end-words), repeated in a dizzyingly complexpattern. The range of effects created by the poetic line varies tremendously depending on its length, its patterns of repetition, and whether the sentence stops at the end of theline (end-stopped) or carries over the end of the line (enjambed). Many of the earliest examples of Old English poetry feature an accentual line with...
-
Metabolism (chemistry) - biology.
nearly perfect balance. Although much remains to be revealed about metabolic processes, biochemists now agree that regulatory, or rate-limiting, enzymes figure largely in the reactionsinvolved ( see Enzyme). Affecting metabolic pathways at the earliest steps, each enzyme molecule has a specific, or active, site that matches, or “fits,” its particular substrate—the compound with which the enzyme forms a product. The precision with which rate-limiting enzymes and substrates join to set off a parti...
-
Interstellar Matter - astronomy.
silhouette of a cloud of dust. At other times, it blocks only a percentage of the light from behind it, a process known by astronomers as extinction . The long, narrow dark lanes in the Milky Way as seen from Earth are examples of extinction. The amount of extinction is different for different wavelengths of light. A2 Reddening Starlight that does not get completely absorbed by interstellar dust can still be changed by the dust’s effects. As light passes through less dense patches of interstel...
-
-
Latin America.
adequate housing and services, most were forced to live in shantytowns that came to encircle all large Latin American cities. One of the key problems facing Latin America in the late 20th century was the rapid rise of external debt during the 1980s. The borrowed money had been used bycorrupt, or at best inefficient, governments in non-productive projects. These large debts meant that many countries had to spend up to 30 percent of their net incometo pay interest on their loans. Some countries, s...
-
Library (institution).
rooms, special galleries for exhibitions, auditoriums for lectures or concerts, computer rooms, children’s rooms, photocopy rooms, and classrooms. A3 Lending Materials As part of their mission to provide information resources to the community, public libraries allow users to borrow items from their collections for limited amounts of time.To be eligible to borrow public library materials, a user must register her or his name, address, and other basic information with the local library’s circulat...