43 résultats pour "drainage"
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drainage - agriculture et agroalimentaire.
4.2 Drains L’intervention la plus élémentaire visant à réduire le taux d’humidité d’un terrain consiste à creuser une tranchée, pour que les eaux ne pouvant pénétrer dans le terrain pargravité puissent couler vers ce creux et, ainsi, détourner une partie des eaux de la surface des terres avoisinantes. Si le terrain est en pente, la tranchée située en partiehaute et perpendiculairement au sens de la pente soustrait une bonne partie des eaux de ruissellement aux terres en aval. De plus, si l’on a...
- drainage.
- Le drainage de la Sologne.
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barrage.
Les tunnels ainsi formés sont souvent transformés et réutilisés après l’achèvement de l’ouvrage. Si les conditions topographiques empêchent la réalisation de canaux de dérivation, un barrage peut être construit en deux étapes. On établit alors un batardeau sur la moitié de la largeur de la rivière, pendant la construction de la partie basse du barrage. Ce batardeau est ensuite enlevé et un second est établi autour de la partie opposée du site. L’élaboration de grands barrages peut s’étendre sur...
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barrage.
L’eau qui retourne à la rivière en aval du barrage ne doit pas avoir la possibilité de creuser ou d’éroder ni le lit de la rivière, ni d’affecter la fondation du barrage par effet decavitation. Ainsi, des plans d’eau, appelés bassins de rétention, sont prévus pour réduire la vitesse de l’eau, et donc son énergie cinétique. Ces bassins constituent unélément majeur du barrage. Le bassin en tablier et le bassin à chocs sont des structures courantes, permettant de diminuer l’énergie élevée de la chu...
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Railroads.
III GAUGES The gauge of track is the distance between the inner edges of the rails at points 1.59 cm (0.626 in) below the top of the heads. In the United States, Canada, theUnited Kingdom, Mexico, Norway, Sweden, and much of continental Europe, the standard gauge is 143.51 cm (56.5 in). Why this measurement became the standard isa matter of speculation. Probably the tradition is inherited from early tramroads built to accommodate wagons with axles 1.5 m (5 ft) long; some of the early edge rail...
- Le drainage de la Sologne (1850-1870 environ)
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La kinésithérapie
(effleurage , pression, pétrissage, etc.) peuvent être mis en œuvre en fonction des objectifs recherchés. En tout premier lieu, celui-ci permet de réchauffer les muscles et de réduire les contractures , tout en apportant des informations au kinésithérapeute sur l'état de son patient (tension nerveuse, sensibil ité à la douleur. . . ). D 'autres approches visent plus directement une efficacité thérapeutique , telles que la technique du tapotement ou cl...
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Sewage Disposal.
greater load on the piping system and the treatment plant. The amount of storm-water drainage to be carried away depends on the amount of rainfall as well as on the runoff or yield of the watershed ( see Drainage). A typical metropolitan area discharges a volume of wastewater equal to about 60 to 80 percent of its total daily water requirements, the rest being used for washingcars and watering lawns, and for manufacturing processes such as food canning and bottling. B Composition The composi...
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North Carolina - geography.
The drainage divide in North Carolina follows the Blue Ridge range on the eastern margin of the mountain region. This is called the “Eastern Continental Divide.” West ofthis divide, rivers drain into the Mississippi River through the Tennessee River and other tributaries of the Ohio River. The French Broad, the largest, and the LittleTennessee flow into the Tennessee River. The New River flows into the Kanawha River of West Virginia which in turn flows into the Ohio River. Most of the state’s ri...
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North Carolina - USA History.
The drainage divide in North Carolina follows the Blue Ridge range on the eastern margin of the mountain region. This is called the “Eastern Continental Divide.” West ofthis divide, rivers drain into the Mississippi River through the Tennessee River and other tributaries of the Ohio River. The French Broad, the largest, and the LittleTennessee flow into the Tennessee River. The New River flows into the Kanawha River of West Virginia which in turn flows into the Ohio River. Most of the state’s ri...
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Florida - USA History.
accidentally introduced into the region in the 1880s, and it spread with alarming rapidity throughout the upper reaches of the river. The plant is very difficult toeradicate, and it has also clogged the channels of other Florida rivers. To increase drainage of the Everglades, which drain naturally to Florida Bay and the Gulf ofMexico, a number of drainage channels and canals have been built across southern Florida. Among the rivers flowing from the peninsula to the Gulf of Mexico are the Suwanne...
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Europe - geography.
movement of a segment of the Earth’s crust against the stable shield during the Caledonian orogeny (about 500 to 395 million years ago) raised the mountains of Ireland,Wales, Scotland, and western Norway. Subsequent erosion has rounded and worn down these mountains in the British Isles, but the peaks of Norway still reach 2,472 m(8,110 ft). The second major geological region, a belt of sedimentary materials, sweeps in an arc from southwestern France northward and eastward through the Low Countri...
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Ohio - geography.
conflict with modified Gulf air and causing frontal or cyclonic storms. Gulf air is dominant in summer. In fall, polar air passing over Lake Erie is modified, delaying thekilling frost along the adjacent shoreline. C1 Temperatures The mean annual temperatures for the state range from 9° C (48° F) in the northeast to 13° C (55° F) in the south. Average January temperatures range from -4° C(24° F) in the west to 2° C (35° F) in the south. July averages are 24° C (76° F) in the south and 23° C (73...
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Ohio - USA History.
conflict with modified Gulf air and causing frontal or cyclonic storms. Gulf air is dominant in summer. In fall, polar air passing over Lake Erie is modified, delaying thekilling frost along the adjacent shoreline. C1 Temperatures The mean annual temperatures for the state range from 9° C (48° F) in the northeast to 13° C (55° F) in the south. Average January temperatures range from -4° C(24° F) in the west to 2° C (35° F) in the south. July averages are 24° C (76° F) in the south and 23° C (73...
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Iraq - country.
The Euphrates begins in Turkey, crosses Syria, and enters Iraq at Abū Kam āl. The flow of the Euphrates into Iraq has been greatly reduced by dams built by Turkeyand Syria. The gradient of the Euphrates above the town of H īt, in west central Iraq, is steep. In the 2,640 km (1,640 mi) from its source in Turkey to H īt, the river fallsfrom 3,000 m (10,000 ft) to a low water elevation of 50 m (170 ft) above sea level, an average drop of 1 m per km (6 ft per mi). In Iraq below H īt the fall is very...
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Géographie FLEUVES ET RIVIERES
Fleuves et rivières qui coupent les montagnes perpendiculai rement. Le réseau hydrographique prend alors un aspect réticulé typique. Le dernier type de réseau est le réseau radial ou étoilé car il res semble tout simplement à une étoile ou aux rayons d'une roue, car les rivières divergent autour d'un sommet. Il apparaît essentiellement à proximité de massifs montagneux en forme de cône ou de dôme comme certains volcans. La densité du drainage Dans...
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Indiana - geography.
Michigan in Michigan. There are about 1,000 small natural lakes in Indiana, chiefly in the northern part of the state. The largest is Lake Wawasee, which covers almost 13 sq km (5 sq mi). Inthe central part of the state there are several lakes that were created behind dams on a number of smaller streams. They include Monroe Lake, near Bloomington; Geistand Eagle Creek reservoirs, northeast and northwest of Indianapolis; and Mississinewa and Huntington reservoirs, north of Marion. C Climate Most...
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Indiana - USA History.
Michigan in Michigan. There are about 1,000 small natural lakes in Indiana, chiefly in the northern part of the state. The largest is Lake Wawasee, which covers almost 13 sq km (5 sq mi). Inthe central part of the state there are several lakes that were created behind dams on a number of smaller streams. They include Monroe Lake, near Bloomington; Geistand Eagle Creek reservoirs, northeast and northwest of Indianapolis; and Mississinewa and Huntington reservoirs, north of Marion. C Climate Most...
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Illinois - geography.
the state before joining the Mississippi River at Grafton. The Illinois has been deepened and straightened and forms part of the Illinois Waterway. The watershed between rivers that flow into the Mississippi river system and rivers that flow into the Great Lakes is low and in many places is not easily discernible. Inwhat is now the Chicago area, explorers had little difficulty portaging, or carrying, their canoes over the low watershed between the Des Plaines River, which flows intothe Illinois,...
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Illinois - USA History.
the state before joining the Mississippi River at Grafton. The Illinois has been deepened and straightened and forms part of the Illinois Waterway. The watershed between rivers that flow into the Mississippi river system and rivers that flow into the Great Lakes is low and in many places is not easily discernible. Inwhat is now the Chicago area, explorers had little difficulty portaging, or carrying, their canoes over the low watershed between the Des Plaines River, which flows intothe Illinois,...
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Définition:
EX(O)-, (EX-4, EXO-) élément préfixe.
exoénergétiques de cette décomposition l'énergie dont elle a besoin (HENRI CAMEFORT, A. GAMA, Sciences naturelles (Classe de philosophie, mathématiques et sciences expérimentales) 1960, page 350 ). exoparasitique. - Maladie exo-parasitique. " Qui est due à un ectoparasite " (confer ect(o)- et Claude Bernard, Principes de médecine expérimentale, 1878, page 283). B.— Substantif. 1. [Le 2e. élément est un élément issu du grec] : exoderme (exo- + -derme*), substantif masculin. Synonymes : ectoderme,...
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Définition:
EX(O)-, (EX-4, EXO-) élément préfixe.
besoin (HENRI CAMEFORT, A. GAMA, Sciences naturelles (Classe de philosophie, mathématiques et sciences expérimentales) 1960, page 350 ). exoparasitique. - Maladie exo-parasitique. " Qui est due à un ectoparasite " (confer ect(o)- et Claude Bernard, Principes de médecine expérimentale, 1878, page 283). B.— Substantif. 1. [Le 2e. élément est un élément issu du grec] : exoderme (exo- + -derme*), substantif masculin. Synonymes : ectoderme, ectoblaste (confer -blaste). Ils [les feuillets] furent dési...
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Great Lakes - Geography.
of 1972 and 1978, have focused on water-quality problems in the Great Lakes. The International Joint Commission on the Great Lakes, established under the BoundaryWaters Treaty, implements and oversees these agreements and has limited authority to regulate obstructions or diversions of boundary waters that would affect thenatural level or flow of lake waters. B Exotic Species The fish populations of the lakes have changed dramatically in the 20th century; changes were wrought at first by overfis...
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Ear.
I
INTRODUCTION
Ear, organ of hearing and balance. Only vertebrates, or animals
line or rotates in any direction. Each canal also contains sensory areas with sensory hair cells that project into a cone-shaped cap of gelatin. Two of the semicircularcanals are in a vertical position and are used to detect vertical movement, such as jumping or falling. The third canal is horizontal and detects horizontal movement,such as turning or spinning. The action of the canals depends on the inertia of the fluid inside. When the motion of the body changes, the fluid lags behind, causing...
- DRAIN, substantif masculin.
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River - geography.
In very large rivers, the water comes from rain that may have fallen as far as 6,000 km (4,000 mi) away. During the journey through rills and streams, the water’s flowmay erode and deposit sediment in the river’s channel and on its floodplain ( see Erosion; Deposit). The biggest rivers usually carry the largest amount of sediment. Yet some of the largest rivers may carry very little sediment because the watershed may not have a lot of sediment. A river carries the most sediment when the flow is...
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Vocabulaire:
CHOLÉDOC(H)(O)-, (CHOLÉDOC-, CHOLÉDOCH-, CHOLÉDOCO-, CHOLÉDOCHO-) élément préfixe.
" Op?ration qui consiste ? anastomoser le canal chol?doque avec le duod?num " (Dictionnaire des termes techniques de m?decine (MARCEL GARNIER, VAL?RY DELAMARE) 1972) chol?dochographie, chol?docho- + grec ??afe?? ? ?crire ?., substantif f?minin. " Radiographie du chol?doque apr?s injection par voie intraveineuse d'un milieu de contraste " (Dictionnaire fran?ais de m?decine et de biologie (ALEXANDRE MANUILA, LUDMILLA MANUILA, M. NICOLE, H. LAMBERT) tome 1 1970) chol?docholithotripsie, chol?doc...
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Henry Morton Stanley.
VI EVALUATION If Stanley was among the most ruthless and driven of Europe’s African explorers, he also was among the most accomplished. Much of what the Western world came toknow about Central Africa, including the drainage of its lakes and rivers, was derived from Stanley’s explorations. Moreover, he was one of the central figures in eventsleading to the Scramble for Africa. His call for the Christianizing of Africans and for the development of commerce with the interior echoed the call Livin...
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Henry Morton Stanley - explorer.
VI EVALUATION If Stanley was among the most ruthless and driven of Europe’s African explorers, he also was among the most accomplished. Much of what the Western world came toknow about Central Africa, including the drainage of its lakes and rivers, was derived from Stanley’s explorations. Moreover, he was one of the central figures in eventsleading to the Scramble for Africa. His call for the Christianizing of Africans and for the development of commerce with the interior echoed the call Livin...
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protection de la nature (faune & Flore).
l'utilisation de la charrue à versoir, associée à la pratique dite de culture propre, qui laissait la surface du sol exposée à toutes les formes d'érosion naturelle. L’érosion des sols dépend de la nature et de la structure du sol, de la couverture végétale, de la pente et des conditions atmosphériques ; de plus, elle peut être aggravéepar certaines pratiques agricoles ( voir dégradation des sols). Les empreintes des agents agricoles sur les sols, facilitant le ruissellement, sont l’une des cau...
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sols, travail des - agriculture et agroalimentaire.
La pollution du sol correspond à l’accumulation de composés toxiques : produits chimiques, sels, matières radioactives ou agents pathogènes qui, tous, ont des effets nocifssur la croissance des plantes et la santé des animaux. L’utilisation accrue d’engrais et de nombreux produits insecticides et fongicides après la fin de la Seconde Guerremondiale est, depuis les années 1960, source d’inquiétude sur l’état des sols. Certes, l’application d’engrais contenant les principaux éléments nutritifs, à...
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Allemagne.
de la mer du Nord. 2.3 Climat L’Allemagne est soumise à un climat de transition, caractérisé par l’affrontement entre les influences océanique et continentale. La continentalité s’accentue vers l’est et lesud-est. Lorsque prévaut l’influence océanique, les pluies hivernales sont abondantes, les étés sont tièdes et pluvieux. L’influence continentale, en revanche, se traduit parde grandes chaleurs estivales et des hivers froids. Elle est surtout marquée à l’est de l’Elbe mais, à partir du mois de...
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Chine.
la partie nord du plateau de l’Ordos, ils sont recouverts d’un fin limon d’origine éolienne, le lœss. Peu compact, le lœss, épais de 200 m, est très sensible à l’érosion(ravinement), la surface des plateaux étant incisée par de nombreux ravins aux parois verticales. Débordant sur le Xinjiang, la Mongolie-Intérieure et le Gansu, le désert de Gobi est un désert de sable et de pierres de type continental. Il s’étend sur le plateau Mongol,situé entre 800 et 1 200 m d’altitude. La végétation devient...
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West Virginia - geography.
Forests, mostly of hardwood varieties, cover 79 percent of West Virginia. The principal commercial species are the oak, yellow poplar, maple, birch, beech, black walnut,hickory, and gum. Softwoods include pines and hemlock firs. Flowering trees include the wild crab apple, dogwood, hawthorn, and redbud. Among the many floweringbushes and plants are the rhododendron, which is the state flower, the laurel, blueberry, hepatica, wild geranium, and black-eyed Susan. Insects and disease, mostly introd...
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West Virginia - USA History.
Forests, mostly of hardwood varieties, cover 79 percent of West Virginia. The principal commercial species are the oak, yellow poplar, maple, birch, beech, black walnut,hickory, and gum. Softwoods include pines and hemlock firs. Flowering trees include the wild crab apple, dogwood, hawthorn, and redbud. Among the many floweringbushes and plants are the rhododendron, which is the state flower, the laurel, blueberry, hepatica, wild geranium, and black-eyed Susan. Insects and disease, mostly introd...
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Oregon - geography.
B Rivers and Lakes The Columbia River forms most of the Oregon-Washington boundary, and with its tributaries this great river drains a large portion of Oregon. From the point where theColumbia first touches the state, at Wallula Gap, the river runs in a shallow gorge, deepening as it approaches the Cascades. This part of the river once had manyrapids and falls, but is now navigable by large vessels because of dams and locks that have been built along much of its length. An important tributary o...
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Oregon - USA History.
B Rivers and Lakes The Columbia River forms most of the Oregon-Washington boundary, and with its tributaries this great river drains a large portion of Oregon. From the point where theColumbia first touches the state, at Wallula Gap, the river runs in a shallow gorge, deepening as it approaches the Cascades. This part of the river once had manyrapids and falls, but is now navigable by large vessels because of dams and locks that have been built along much of its length. An important tributary o...
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Missouri - geography.
Saint Francois Mountains, at the eastern end of the crest of the dome. Only in these mountains have the sedimentary rocks been sufficiently eroded away so that theunderlying igneous rocks are exposed. They form the rounded, knoblike peaks of an old mountain range. The peaks project, in isolation or in clusters, between 230 and300 m (750 and 1,000 ft) above the surrounding sedimentary basins. One of these knobs, Taum Sauk Mountain, reaches 540 m (1,772 ft) above sea level and is thehighest point...
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Missouri - USA History.
Saint Francois Mountains, at the eastern end of the crest of the dome. Only in these mountains have the sedimentary rocks been sufficiently eroded away so that theunderlying igneous rocks are exposed. They form the rounded, knoblike peaks of an old mountain range. The peaks project, in isolation or in clusters, between 230 and300 m (750 and 1,000 ft) above the surrounding sedimentary basins. One of these knobs, Taum Sauk Mountain, reaches 540 m (1,772 ft) above sea level and is thehighest point...
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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...
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Native Americans of North America.
addition to smallpox and measles, explorers and colonists brought a host of other diseases: bubonic plague, cholera, typhoid fever, scarlet fever, pleurisy, mumps,diphtheria, pneumonia, whooping cough, malaria, yellow fever, and various sexually transmitted infections. Despite the undisputed devastation wreaked on Indian populations after European contact, native populations showed enormous regional variability in their response todisease exposure. Some peoples survived and, in some cases, even...
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Native Americans of North America - Canadian History.
addition to smallpox and measles, explorers and colonists brought a host of other diseases: bubonic plague, cholera, typhoid fever, scarlet fever, pleurisy, mumps,diphtheria, pneumonia, whooping cough, malaria, yellow fever, and various sexually transmitted infections. Despite the undisputed devastation wreaked on Indian populations after European contact, native populations showed enormous regional variability in their response todisease exposure. Some peoples survived and, in some cases, even...