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Lift (soaring)
Lift is a meteorological phenomenon used as an energy source by soaring aircraft and soaring birds. The most common human application of lift is in sport and recreation. The three air sports that use soaring flight are: gliding, hang gliding and paragliding. Energy can be gained by using rising air from four sources: * Thermals (where air rises due to heat), * Ridge lift, where air is forced upwards by a slope, * Wave lift, where a mountain produces a standing wave, * Convergence, where two air masses meet In dynamic soaring it is also possible to gain energy, though this uses differences in wind speeds rather than rising air. Thermals Thermals are columns of rising air that are formed on the ground through the warming of the surface by sunlight. If the air contains enough moisture, the water will condense from the rising air and form cumulus clouds. Thermal lift is often used by birds, such as raptors, vultures and storks. Although thermal lift was known to the Wri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorology
Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not begin until the 18th century. The 19th century saw modest progress in the field after weather observation networks were formed across broad regions. Prior attempts at prediction of weather depended on historical data. It was not until after the elucidation of the laws of physics, and more particularly in the latter half of the 20th century the development of the computer (allowing for the automated solution of a great many modelling equations) that significant breakthroughs in weather forecasting were achieved. An important branch of weather forecasting is marine weather forecasting as it relates to maritime and coastal safety, in which weather effects also include atmospheric interactions with large bodies of water. Meteorological ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Murray (publishing House)
John Murray is a British publisher, known for the authors it has published in its long history including, Jane Austen, Sir Arthur Conan Doyle, Lord Byron, Charles Lyell, Johann Wolfgang von Goethe, Herman Melville, Edward Whymper, Thomas Malthus, David Ricardo, and Charles Darwin. Since 2004, it has been owned by conglomerate Lagardère under the Hachette UK brand. Business publisher Nicholas Brealey became an imprint of John Murray in 2015. History The business was founded in London in 1768 by John Murray (1737–1793), an Edinburgh-born Royal Marines officer, who built up a list of authors including Isaac D'Israeli and published the ''English Review''. John Murray the elder was one of the founding sponsors of the London evening newspaper '' The Star'' in 1788. He was succeeded by his son John Murray II, who made the publishing house important and influential. He was a friend of many leading writers of the day and launched the '' Quarterly Review'' in 1809. He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoxia (medical)
Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level. Hypoxia may be classified as either '' generalized'', affecting the whole body, or ''local'', affecting a region of the body. Although hypoxia is often a pathological condition, variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise.. Hypoxia differs from hypoxemia and anoxemia, in that hypoxia refers to a state in which oxygen present in a tissue or the whole body is insufficient, whereas hypoxemia and anoxemia refer specifically to states that have low or no oxygen in the blood. Hypoxia in which there is complete absence of oxygen supply is referred to as anoxia. Hypoxia can be due to external causes, when the breathing gas is hypoxic, or internal causes, such as reduced effectiveness of gas transfer in the lungs, reduced capacity of the blood to carry oxygen, compromised gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolf Hirth
Wolfram Kurt Erhard Hirth (28 February 1900 – 25 July 1959) was a German gliding pioneer and sailplane designer. He was a co-founder of Schempp-Hirth, still a renowned glider manufacturer.Segelflugbildkalendar 2011 Hirth was born in Stuttgart, the son of an engineer and tool-maker. He was the younger brother of Hellmuth, who founded the famous Hirth aircraft engine manufacturing company. Early years As a young man, Hirth took up gliding and was soon drawn to the Wasserkuppe, then the focus of the German gliding movement, earning his pilot's licence in 1920. In 1924, Hirth lost a leg after a motorcycle accident. From then on, he would fly while wearing a wooden prosthesis. He had the fibula from his amputated leg fashioned into a cigarette holder In 1928, he graduated from the Technical University of Stuttgart with a diploma in engineering and began to focus on aircraft construction. Over the next decade, he would also tour the world, promoting gliding throughout Europe, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lee Waves
In meteorology, lee waves are atmospheric stationary waves. The most common form is mountain waves, which are atmospheric internal gravity waves. These were discovered in 1933 by two German glider pilots, Hans Deutschmann and Wolf Hirth, above the Krkonoše. They are periodic changes of atmospheric pressure, temperature and orthometric height in a current of air caused by vertical displacement, for example orographic lift when the wind blows over a mountain or mountain range. They can also be caused by the surface wind blowing over an escarpment or plateau, or even by upper winds deflected over a thermal updraft or cloud street. The vertical motion forces periodic changes in speed and direction of the air within this air current. They always occur in groups on the lee side of the terrain that triggers them. Sometimes, mountain waves can help to enhance precipitation amounts downwind of mountain ranges. Usually a turbulent vortex, with its axis of rotation parallel t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orographic Lift
Orographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and create clouds and, under the right conditions, precipitation. Orographic lifting can have a number of effects, including precipitation, rain shadowing, leeward winds, and associated clouds. Precipitation Precipitation induced by orographic lift occurs in many places throughout the world. Examples include: * The Mogollon Rim in central Arizona * The western slope of the Sierra Nevada range in California * The mountains near Baja California North – specifically La Bocana to Laguna Hanson. * The windward slopes of Khasi and Jayantia Hills (see Mawsynram) in the state of Meghalaya in India. * The Western Highlands of Yemen, which receive by far the most rain in Arabia. * The Western Ghats that run along India's western coast. * The Gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Station
A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Power stations are generally connected to an electrical grid. Many power stations contain one or more generators, a rotating machine that converts mechanical power into three-phase electric power. The relative motion between a magnetic field and a conductor creates an electric current. The energy source harnessed to turn the generator varies widely. Most power stations in the world burn fossil fuels such as coal, oil, and natural gas to generate electricity. Low-carbon power sources include nuclear power, and an increasing use of renewables such as solar, wind, geothermal, and hydroelectric. History In early 1871 Belgian inventor Zénobe Gramme invented a generator powerful enough to produce power on a commercial scale for industry. In 1878, a hydroelectric power station was designed and built ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asphalt
Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used. Full text at Internet Archive (archive.org) The word is derived from the Ancient Greek ἄσφαλτος ''ásphaltos''. The largest natural deposit of asphalt in the world, estimated to contain 10 million tons, is the Pitch Lake located in La Brea in southwest Trinidad ( Antilles island located on the northeastern coast of Venezuela), within the Siparia Regional Corporation. The primary use (70%) of asphalt is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs. In material sciences and engineering, the terms "as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
