226 résultats pour "300"
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VIRUS
Les virus sont des entités de dimensions extrêmement réduites, de 10 à
300 millionièmes de millimètre (de 10 à 300 nanomètres), capables de pénétrer à
l'intérieur des Bactéries ou des cellules animales ou végétales, et de les détruire.
2 éclate, les laissant se propager dans l'organisme, prêtes à infecter de nouvelles cellules. La duplication des virus dans la cellule peut se faire en quelques secondes, ou en quelques heures. Parfois, la multiplication ne commence qu'au bout de plusieurs jours ou plusieurs mois, voire plusieurs années. Dans ce cas, on parle de phase silencieuse ou de période de latence, parce que le virus est là, mais tout se passe comme s'il ne l’était pas. Quand ils se reproduisent, les virus n’altèrent pas...
- Sialis: Un survivant de formes fossiles datant de 300 millions d'années.
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Plus de 300 photographies nouvelles de la planète Mercure ont été prises par la sonde spatiale Mariner 10
U.R.S.S. Les expériences sur orbite terrestre des vaisseaux cosmiques « Soyouz 14 ,. et .. Soyouz 15 ,. avec la station orbitale .. Saliout 3 ,. Le 25 juin, la section orbitale russe « Sa liout 3 » a été mise sur orbite circum terrestre selon les paramètres suivants : apogée de 270 km, périgée de 219 km, période initiale de révolution de 89,1 minutes et inclinaison sur l'équateur de 51,6 degrés. Rappelons pour mémoire les lan...
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Relativity
I
INTRODUCTION
Albert Einstein
In 1905 German-born American physicist Albert Einstein published his first paper outlining the theory of relativity.
in calculating very large distances or very large aggregations of matter. As the quantum theory applies to the very small, so the relativity theory applies to the verylarge. Until 1887 no flaw had appeared in the rapidly developing body of classical physics. In that year, the Michelson-Morley experiment, named after the American physicistAlbert Michelson and the American chemist Edward Williams Morley, was performed. It was an attempt to determine the rate of the motion of the earth through t...
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big bang, théorie du - astronomie.
4 SCÉNARIO DU BIG BANG 4.1 Avant 10 -43 seconde : superforce ou gravité quantique La phase primordiale de l'Univers est le domaine de la superforce (appelée aussi gravité quantique), qui unifie alors les quatre connues ( voir théorie des champs unifiée). À ce stade d'évolution, la matière n’est pas encore née, seul règne le vide au sens quantique du terme (apparition et disparition de particules virtuelles). 4.2 De 10 -43 à 10 -35 seconde : grande unification des forces Au temps de Planck, l...
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Helicopter.
naturally flaps down so as to increase lift. Flapping allows the differences in lift caused by uneven rotor tip speed to cancel out, producing a stable ride. Many helicoptersuse mechanical hinges with lubricated bearings, but some use flexible straps made of a composite material in order to reduce the required maintenance. Helicopters require different amounts of lift and thrust at different times during flight, because the aerodynamic forces acting on them change during hovering andacceleration...
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Asia - Geography.
Borneo, the world’s third largest island after Greenland and New Guinea. To the southeast is the Timor Sea separating the Asian island of Timor from the Australiancontinent. The Indian subcontinent is flanked by the Bay of Bengal on the east and the Arabian Sea on the west. The island of Sri Lanka and the much smaller Maldives andNicobar Islands trail away to the south. The Arabian Sea’s Gulf of Aden, the Red Sea, the Mediterranean Sea, and the Black Sea form an arc along the western rim of Asia...
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Asia - History.
Borneo, the world’s third largest island after Greenland and New Guinea. To the southeast is the Timor Sea separating the Asian island of Timor from the Australiancontinent. The Indian subcontinent is flanked by the Bay of Bengal on the east and the Arabian Sea on the west. The island of Sri Lanka and the much smaller Maldives andNicobar Islands trail away to the south. The Arabian Sea’s Gulf of Aden, the Red Sea, the Mediterranean Sea, and the Black Sea form an arc along the western rim of Asia...
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- Biographie de HÉGÉSIAS. (Vers 300 av. J.-C.)
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India - geografía.
valiosas de madera, entre ellas la teca. En las tierras bajas pantanosas hay grandes regiones de jungla impenetrable y también a lo largo de las laderas bajas de los Ghatesoccidentales. La vegetación del Decán es menos exuberante, pero a través de toda la península se pueden encontrar espesuras de bambú, palmera y árboles caducifolios. Las selvas, llanuras, colinas y montañas de la India están habitadas por gran variedad de vida animal. Los felinos están bien representados, con tigres y panteras...
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Ocean and Oceanography.
of sediment. When studied in sedimentary core samples, which can represent many millions of years of deposits, they provide a detailed and continuous history of theearth’s environmental changes. The record is particularly informative for the most recent 2 million to 5 million years, during which major fluctuations in global climatehave occurred. Successive ice ages can be traced by the relative scarcity or abundance of the shells of warm-water and cold-water diatoms in various layers of asedimen...
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Ocean and Oceanography - Geography.
of sediment. When studied in sedimentary core samples, which can represent many millions of years of deposits, they provide a detailed and continuous history of theearth’s environmental changes. The record is particularly informative for the most recent 2 million to 5 million years, during which major fluctuations in global climatehave occurred. Successive ice ages can be traced by the relative scarcity or abundance of the shells of warm-water and cold-water diatoms in various layers of asedimen...
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Canada.
Six general landform regions are distinguishable in Canada: the Appalachian Region, the Great Lakes and St. Lawrence Lowlands, the Canadian Shield, the Great Plains,the Canadian Cordillera, and the Canadian Arctic Archipelago. B1 Appalachian Region and Great Lakes and St. Lawrence Lowlands Eastern Canada consists of the Appalachian Region and the Great Lakes and St. Lawrence Lowlands. The Appalachian Region embraces Newfoundland Island, NovaScotia, New Brunswick, Prince Edward Island, and the G...
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Canada - country.
Six general landform regions are distinguishable in Canada: the Appalachian Region, the Great Lakes and St. Lawrence Lowlands, the Canadian Shield, the Great Plains,the Canadian Cordillera, and the Canadian Arctic Archipelago. B1 Appalachian Region and Great Lakes and St. Lawrence Lowlands Eastern Canada consists of the Appalachian Region and the Great Lakes and St. Lawrence Lowlands. The Appalachian Region embraces Newfoundland Island, NovaScotia, New Brunswick, Prince Edward Island, and the G...
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Canada - Canadian History.
Six general landform regions are distinguishable in Canada: the Appalachian Region, the Great Lakes and St. Lawrence Lowlands, the Canadian Shield, the Great Plains,the Canadian Cordillera, and the Canadian Arctic Archipelago. B1 Appalachian Region and Great Lakes and St. Lawrence Lowlands Eastern Canada consists of the Appalachian Region and the Great Lakes and St. Lawrence Lowlands. The Appalachian Region embraces Newfoundland Island, NovaScotia, New Brunswick, Prince Edward Island, and the G...
- Moulin à grains chinois de la dynastie Han De -300 à +300 - Matériel funéraire
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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,...
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Africa - Geography.
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,...
- Buse des Galapagos: Il n'en reste guère plus de 300 au monde.
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New Mexico - geography.
New Mexico’s major river is the Río Grande, originating in southern Colorado, and flowing southward for 760 km (470 mi) through the state. Between the San LuisValley and Española Valley the river flows in a deep canyon known as the Río Grande Gorge; then, below White Rock Canyon, it flows through several valleys containingagricultural land. Most of the water of the Río Grande is used to irrigate these valleys. The Río Grande’s waterflow in New Mexico is extremely low. One of the major tributarie...
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New Mexico - USA History.
New Mexico’s major river is the Río Grande, originating in southern Colorado, and flowing southward for 760 km (470 mi) through the state. Between the San LuisValley and Española Valley the river flows in a deep canyon known as the Río Grande Gorge; then, below White Rock Canyon, it flows through several valleys containingagricultural land. Most of the water of the Río Grande is used to irrigate these valleys. The Río Grande’s waterflow in New Mexico is extremely low. One of the major tributarie...
- Spa. ville de Belgique, au sud-est de Liège. 10 300
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Island - geographie.
fast ausschließlich Nachkommen normannischer und keltischer Einwanderer. In den vierziger Jahren des 20. Jahrhunderts setzte eine große Landflucht ein. Etwa 93 Prozentder Isländer leben heute in Städten. Zu Beginn des 20. Jahrhunderts lag der Anteil der Stadtbevölkerung noch bei 20 Prozent. Die Siedlungsgrenze liegt bei etwa 200 Meternüber dem Meeresspiegel. Die isländische Bevölkerung hat eine der höchsten Lebenserwartungen der Welt. Diese liegt für Männer bei 78,4 Jahren und für Frauen bei 82,...
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Mesoamerica.
for cooking. In other regions, the earliest ceramics are more sophisticated technically and aesthetically. At around 1800 BC in the Pacific coastal region of Soconusco (in what is now southeastern Chiapas State, Mexico), the earliest pottery was very complex both in forms and decoration. It seems to have had a social function and beenused primarily for ritual feasting. III MAJOR CIVILIZATIONS Over a period of 3000 years, beginning in about 1500 BC, a number of important cultures emerged in M...
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China - geographie.
sind nährstoffreich und werden landwirtschaftlich genutzt. Das breite Flussdelta des Xi Jiang wird auch Kantondelta genannt. 2.1. 6 Die Tibetische Hochebene Im abgelegenen äußersten Südwesten Chinas liegt die Tibetische Hochebene. Das zerklüftete Bergland gehört zu den höchstgelegenen Plateauregionen der Welt. Diedurchschnittliche Höhe beträgt 4 510 Meter. Die Hochebene wird von Hochgebirgen begrenzt; dies sind im Süden Himalaya, im Westen Pamir und Karakorum und im NordenKunlun Shan und Qilian...
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Alaska - geography.
depression surrounded by highlands and have the coldest winter and hottest summer temperatures in Alaska. Once the Kuskokwim River passes through theKuskokwim Mountains, it forms the southern edge of a vast lake-studded alluvial plain bounded on the north by the Yukon River. This water-logged lowland is a majorsummer nesting area for birds. Fairbanks is the major city in this region, while Fort Yukon is the major community in the Yukon Flats and Bethel the largest settlementon the Lower Kuskokwi...
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Alaska - USA History.
depression surrounded by highlands and have the coldest winter and hottest summer temperatures in Alaska. Once the Kuskokwim River passes through theKuskokwim Mountains, it forms the southern edge of a vast lake-studded alluvial plain bounded on the north by the Yukon River. This water-logged lowland is a majorsummer nesting area for birds. Fairbanks is the major city in this region, while Fort Yukon is the major community in the Yukon Flats and Bethel the largest settlementon the Lower Kuskokwi...
- Au milieu de la mer Méditerranée, à 100 km de la Sicile et 300 km de l'Afrique, Malte a une grande importance stratégique.
- La diarrhée La diarrhée est définie médicalement par un poids de selles supérieur à 300 g par jour.
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Japanese Art and Architecture
I
INTRODUCTION
Otani Oniji as Eitoku
Otani Oniji as Eitoku is one of a number of woodblock prints created by the artist T? sh ?sai Sharaku between 1794 and
1795 during the Edo period in Japan.
Jō mon PotteryJapan’s J ōmon people, who thrived from 10,000 to 300 bc, made distinctive pottery for boiling, steaming, and storing food.The pots were made with coils of clay and then decorated by rolling carved sticks, plant fibers, or braided cords over theouter surface. This cord-marked (j ōmon) pottery gave the culture its name.Scala/Art Resource, NY The first settlers of Japan, the J ōmon people (10,000?-300? BC), named for the cord markings that decorated the surfaces of their clay vessel...
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Saturne - astronomie.
diamètres très variés, allant de 5.10 -6 m à environ 10 m. Ainsi, malgré leur apparence impressionnante, les anneaux de Saturne sont extrêmement minces — leur épaisseur n'excédant pas 1,5 km — et ne contiennent que très peu de matière. La séparation apparente entre les anneaux A et B est appelée division de Cassini, du nom de l'astronome français Jean-Dominique Cassini, qui l’a découverte auXVII e siècle. Un trou moins visible au sein de l’anneau A est appelé division de Encke, en hommage à l’as...
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Fluss - geographie.
Zustand; fast alle sind kanalisiert, begradigt und reguliert. Verfasst von:Peter GöbelDie längsten Flüsse der Erde Rang Fluss Mündung Land Kontinent Länge 1 Nil Mittelmeer Burundi, Ruanda,Tansania, Uganda,Sudan, Ägypten Afrika 6 671 km 2 Amazonas Atlantischer Ozean Brasilien, Peru, Ecuador,Bolivien, Venzuela Südamerika 6 400 km 3 Jangtsekiang Ostchinesisches Meer China Asien 6 300 km 4 Mississippi (mitMissouri) Golf von Mexiko USA Nordamerika 5 970 km 5 Jenissej Karasee Russland Asien 5 550...
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- «Titre», Nous constatons, sauf erreur de notre part, que notre facture n° F 0772 portant sur 300 briquets n'a fait à ce jour l'objet d'aucun règlement.
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train à grande vitesse [TGV].
fonctionner comme un aéroport local, situé en dehors de la zone urbaine et isolé par excellence. Plus de 80 p. 100 du trafic des voyageurs de l’ancienne ligne Paris-Lyon est transféré sur la nouvelle infrastructure qui effectue la liaison en deux heures, à la vitesse commerciale de 270 km/h. La couleur orange du TGV Sud-Est — caractéristique des TGV de première génération qui ont été retirés du paysage en mai 2001 —, et son esthétique sont l’œuvre de Jacques Cooper. 2.4. 2 Le TGV Atlantique Le...
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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...
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Australia - geografía.
ciclones en invierno. Casi todos los años, la sequía afecta a algunas áreas de Australia, pero también son frecuentes las inundaciones locales y los ciclones tropicales. 2.5 Recursos naturales Australia es rica en recursos minerales. Los más destacados, en cuanto a valor comercial, son: la bauxita, el carbón bituminoso, el mineral de hierro, el níquel, el oro, elplomo, el zinc, la plata, el lignito y el petróleo y el gas natural, ambos extraídos en las costas. Los yacimientos de gemas más famos...
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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...
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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...
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Arizona - geography.
of the Mogollon Rim, the Little Colorado draws very little water from a relatively large watershed, usually containing a mere trickle of water in its riverbed. The ColoradoRiver’s principal tributary is the Gila River, which flows all the way across the southern part of the state from New Mexico to the California border. From the mountainsand plateaus of central Arizona, the Gila River receives the Salt, Agua Fria, and Hassayampa rivers. The Salt River is itself fed by the Verde River. The Gila...
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Arizona - USA History.
of the Mogollon Rim, the Little Colorado draws very little water from a relatively large watershed, usually containing a mere trickle of water in its riverbed. The ColoradoRiver’s principal tributary is the Gila River, which flows all the way across the southern part of the state from New Mexico to the California border. From the mountainsand plateaus of central Arizona, the Gila River receives the Salt, Agua Fria, and Hassayampa rivers. The Salt River is itself fed by the Verde River. The Gila...
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- Vase chinois de la dynastie Han De -300 à +300 - Décors peints, après cuisson, imitant le bronze
- Morena (sierra), région montagneuse de l'Espagne, entre la Castille et l'Andalousie, d'une altitude moyenne de 800 m et atteignant 1 300 m dans la sierra Madrona.
- Durch seine zentrale Lage im Mittelmeer, 100 km von Sizilien und 300 km von Afrika, hat Malta große strategische Bedeutung.
- GALAXIES La galaxie la plus grande dans le Groupe Local : il s'agit d'Andromède (M31), dont la taille est égale à une fois et demie celle de notre Galaxie, et qui comprend plus de 300 amas globulaires.
- Blennie à lèvres lisses Sautillante et végétarienne Parmi les innombrables espèces de blennies, plus de 300 selon les auteurs, aux coloris et aux comportements si différents, les blennies à lèvres lisses, de la sous-famille des Salariinés, sont qualifiées de végétariennes.
- Commonwealth d'Australie (fiche d'identité) Commonwealth of Australia Code international: AUS Superficie: 7 682 300 km2 Population: 17 073 000 h.
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TERRE
FLEUVES
Le fleuve ayant le débit le plus important est l'Amazone, avec 113 300 m3 d'eau par
seconde (par comparaison, le plus grand fleuve français, le Rhin, a un débit de 2
200 m3/s).
2 MONTAGNES La montagne la plus élevée est le mont Everest, dans l’Himalaya, au Tibet, qui mesure 8 848 m. MINÉRAUX ET ROCHES La roche la plus ancienne identifiée jusqu’à présent a été découverte au Canada, en mai 1984. Son âge est estimé à 3,96 milliards d’années. PIERRES PRÉCIEUSES Le diamant le plus grand est le Cullinan, un diamant de 3 106 carats, trouvé dans la région de Pretoria (Afrique du Sud), le 26 janvier 1905. Taillé, il permit d'obtenir 106 diamants plus petits. Le rubis le plus g...
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Greek Mythology
I
INTRODUCTION
Temple of Apollo at Didyma
The Greeks built the Temple of Apollo at Didyma, Turkey (about 300 bc).
A1 The Creation of the Gods According to Greek myths about creation, the god Chaos (Greek for “Gaping Void”) was the foundation of all things. From Chaos came Gaea (“Earth”); the bottomlessdepth of the underworld, known as Tartarus; and Eros (“Love”). Eros, the god of love, was needed to draw divinities together so they might produce offspring. Chaosproduced Night, while Gaea first bore Uranus, the god of the heavens, and after him produced the mountains, sea, and gods known as Titans. The Tita...
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- Bermudes (îles) Archipel britannique de l'Atlantique groupant plus de 300 îlots d'origine corallienne, à quelque 900 km du littoral nord-américain; 53,5 km2, dont 39 pour la seule Grande Bermude; 59 800 h.
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Rusia - ficha de geographia.
Primorsk (territorio) 2.068.200 (2002) Tiumen (región administrativa) 3.265.700 (2002) Tomsk (región administrativa) 1.046.000 (2002) Tula (región administrativa) 1.675.700 (2002) Tuvá (república federada) 310.300 (2002) Tver (región administrativa) 1.472.600 (2002) Udmurtia (república federada) 1.616.200 (2002) Uliánovsk (región administrativa) 1.382.300 (2002) Vladímir (región administrativa) 1.524.900 (2002) Volgogrado (región administrativa) 2.702.500 (2002) Vologda (región administrativa) 1...