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Наука (от латинского слова scientia , что означает «знание») - это систематическое предприятие, которое создает и систематизирует знания в форме проверяемых объяснений и предсказаний о Вселенной .
Самые ранние корни науки можно проследить до Древнего Египта и Месопотамии примерно с 3000 по 1200 год до нашей эры. Их вклад в математику , астрономию и медицины вошли и в форме греческой натурфилософии в классической древности , в результате чего было сделаны формальные попытки дать объяснение событий в физическом мире на основе естественных причин. После падения Западной Римской империи в первые века (400–1000 гг. Н.э.) средневековья в Западной Европе ухудшилось знание греческих представлений о мире., но сохранилась в мусульманском мире во время Золотого века ислама . Восстановление и ассимиляция греческих работ и исламских исследований в Западной Европе с 10 по 13 век возродили « натурфилософию », которая позже была преобразована Научной революцией , начавшейся в 16 веке, когда новые идеи и открытия отошли от прежних греческих концепций и традиции. Научный метод вскоре сыграл большую роль в создании знаний и он не был до 19 - го века , что многие институциональные и профессиональныеначали складываться особенности науки; вместе с заменой «натурфилософии» на «естествознание».
Современная наука обычно делится на три основные отрасли, которые состоят из естественных наук (например, биологии , химии и физики ), изучающих природу в самом широком смысле; в социальных науках (например, экономика , психология и социология ), что изучение отдельных лиц и общества; и формальные науки (например, логика , математика и теоретическая информатика), которые изучают абстрактные понятия. Однако существуют разногласия относительно того, действительно ли формальные науки представляют собой науку, поскольку они не полагаются на эмпирические данные . Дисциплины, использующие существующие научные знания для практических целей, такие как инженерия и медицина, называются прикладными науками .
Наука основана на исследованиях , которые обычно проводятся учеными, работающими в академических и исследовательских учреждениях , государственных учреждениях и компаниях . Практическое влияние научных исследований привело к появлению научных политик, которые стремятся повлиять на научное предприятие, отдавая приоритет развитию коммерческой продукции , вооружений , здравоохранения , общественной инфраструктуры и защиты окружающей среды . ( Полная статья ... )
Выбранная статья
Ураган Дин был самым сильным тропическим циклоном в атлантическом сезоне ураганов 2007 года . Это был самый интенсивный в Северной Атлантике ураган , так как ураган Вильма в 2005 году , связывая на восьмойцелом. Кроме того, он сделал четвертое наиболее интенсивные ураганыАтлантике примыкания . Кабо - Верде урагана , который формируется на 13 августа 2007 года, Дин взялзапад-северозапад путь от восточнойАтлантического океана через Лючия канал Сен и в Карибском бассейне. Он перерос в сильный ураган , достигнув категории 5 по шкале ураганов Саффира – Симпсона.перед тем, как пройти 20 августа к югу от Ямайки . Шторм достиг берега на полуострове Юкатан 21 августа с максимальной интенсивностью. Он пересек полуостров и вышел в слабый залив Кампече , но все еще оставался ураганом. Он ненадолго укрепился, прежде чем 22 августа совершил второй выход на берег около Теколутлы в мексиканском штате Веракрус . Дин переместился на северо-запад, превратившись в остаточный минимум, который беспрепятственно рассеялся над юго-западом Соединенных Штатов. Дин был вторым по интенсивности тропическим циклоном в мире в 2007 году по давлению, уступая только циклону Джорджу в австралийском регионе и равному с Феликсом.как самый сильный в мире с точки зрения продолжительности ветра продолжительностью 1 мин.
Сильные ветры, волны, дожди и штормовые нагоны в результате урагана стали причиной гибели по меньшей мере 45 человек в десяти странах и причинили ущерб в размере 1,66 миллиарда долларов США. Впервые столкнувшись с островами Малых Антильских островов , путь Дина через Карибский бассейн опустошил сельскохозяйственные культуры, особенно Мартинику и Ямайку . Достигнув Мексики, ураган Дин был ураганом категории 5, но он не прошел мимо крупных населенных пунктов, а его исключительный выход на сушу категории 5 не привел к гибели людей и не вызвал меньшего ущерба, чем на Карибских островах, он прошел как шторм категории 2. ( Полная статья ... )
RSPB Dearne Valley Old Moor is an 89-hectare (220-acre) wetlands nature reserve in the Dearne Valley near Barnsley, South Yorkshire, run by the Royal Society for the Protection of Birds (RSPB). It lies on the junction of the A633 and A6195 roads and is bordered by the Trans Pennine Trail long-distance path. Following the end of coal mining locally, the Dearne Valley had become a derelict post-industrial area, and the removal of soil to cover an adjacent polluted site enabled the creation of the wetlands at Old Moor.
Old Moor is managed to benefit bitterns, breeding waders such as lapwings, redshanks and avocets, and wintering golden plovers. A calling male little bittern was present in the summers of 2015 and 2016. Passerine birds include a small colony of tree sparrows and good numbers of willow tits, thriving here despite a steep decline elsewhere in the UK. (Full article...)- At Royal Botanic Gardens, Cranbourne, Melbourne, Victoria, Australia
The black-shouldered kite (Elanus axillaris), also known as the Australian black-shouldered kite, is a small raptor found in open habitat throughout Australia. It resembles similar species found in Africa, Eurasia and North America, including the black-winged kite, a species that has in the past also been called "black-shouldered kite". Measuring around 35 cm (14 in) in length with a wingspan of 80–100 cm (31–39 in), the adult black-shouldered kite has predominantly grey-white plumage and prominent black markings above its red eyes. It gains its name from the black patches on its wings. The primary call is a clear whistle, uttered in flight and while hovering. It can be confused with the related letter-winged kite in Australia, which is distinguished by the striking black markings under its wings.
The species forms monogamous pairs, breeding between August and January. The birds engage in aerial courtship displays which involve high circling flight and ritualised feeding mid-air. Three or four eggs are laid and incubated for around thirty days. Chicks are fully fledged within five weeks of hatching and can hunt for mice within a week of leaving the nest. Juveniles disperse widely from the home territory. The black-shouldered kite hunts in open grasslands, searching for its prey by hovering and systematically scanning the ground. It mainly eats small rodents, particularly the introduced house mouse, and has benefitted from the modification of the Australian landscape by agriculture. It is rated as least concern on the International Union for Conservation of Nature (IUCN)'s Red List of "Endangered species." (Full article...) - A colony of little red flying foxes (Pteropus scapulatus)
Megabats constitute the family Pteropodidae of the order Chiroptera (bats). They are also called fruit bats, Old World fruit bats, or—especially the genera Acerodon and Pteropus—flying foxes. They are the only member of the superfamily Pteropodoidea, which is one of two superfamilies in the suborder Yinpterochiroptera. Internal divisions of Pteropodidae have varied since subfamilies were first proposed in 1917. From three subfamilies in the 1917 classification, six are now recognized, along with various tribes. As of 2018, 197 species of megabat had been described.
The understanding of the evolution of megabats has been determined primarily by genetic data, as the fossil record for this family is the most fragmented of all bats. They likely evolved in Australasia, with the common ancestor of all living pteropodids existing approximately 31 million years ago. Many of their lineages probably originated in Melanesia, then dispersed over time to mainland Asia, the Mediterranean, and Africa. Today, they are found in tropical and subtropical areas of Eurasia, Africa, and Oceania. (Full article...) - Whitelee Wind Farm is operated by ScottishPower Renewables and is the largest on-shore wind farm in the United Kingdom with a total capacity of 539 megawatts (MW).
The production of renewable energy in Scotland is a topic that has come to the fore in technical, economic, and political terms during the opening years of the 21st century. The natural resource base for renewable energy is high by European, and even global standards, with the most important potential sources being wind, wave, and tide. Renewables produced 97.4% of Scotland's electricity in 2020, mostly from the country's wind power.
In 2015, Scotland generated 59% of its electricity consumption through renewable sources, exceeding the country's goal of 50% renewable electricity by that year. At the start of 2020, Scotland had 11.8 gigawatts (GW) of installed renewable electricity capacity, which produced approximately 25% of total UK renewable generation (119,000 GWh). In 2018, Scotland exported over 28 per cent of generation and in 2019 renewable electricity generation made up 90% of gross electricity consumption. In decreasing order of capacity, Scotland's renewable generation comes from onshore wind, hydropower, offshore wind, solar PV and biomass. (Full article...)
Hurricane Danny was the only hurricane to make landfall in the United States during the 1997 Atlantic hurricane season, and the second hurricane and fourth tropical storm of the season. The system became the earliest-formed fifth tropical or subtropical storm of the Atlantic season in history when it attained tropical storm strength on July 17, and held that record until the 2005 Atlantic hurricane season when Tropical Storm Emily broke that record by several days. Like the previous four tropical or subtropical cyclones of the season, Danny had a non-tropical origin, after a trough spawned convection that entered the warm waters of the Gulf of Mexico. Danny was guided northeast through the Gulf of Mexico by two high pressure areas, a rare occurrence in the middle of July. After making landfall on the Gulf Coast, Danny tracked across the southeastern United States and ultimately affected parts of New England with rain and wind.
Danny is notable for its extreme rainfall, the tornadoes generated by it, and the destruction it produced on its path, causing a total of nine fatalities and $100 million (1997 USD, $159 million 2021 USD) in damage. The storm dropped a record amount of rainfall for Alabama, as at least 36.71 inches (932 mm) fell on Dauphin Island. Flooding, power outages, and erosion occurred in many areas of the Gulf Coast, and rescues had to be executed from flooded roadways. Tornadoes generated by Danny on the East Coast caused a great amount of damage. Of the nine fatalities caused by Danny, one happened off the coast of Alabama, four occurred in Georgia, two occurred in South Carolina, and two occurred in North Carolina. (Full article...)
Acacia pycnantha, most commonly known as the golden wattle, is a tree of the family Fabaceae native to southeastern Australia. It grows to a height of 8 m (26 ft) and has phyllodes (flattened leaf stalks) instead of true leaves. Sickle-shaped, these are between 9 and 15 cm (3 1⁄2 and 6 in) long, and 1–3.5 cm (1⁄2–1 1⁄2 in) wide. The profuse fragrant, golden flowers appear in late winter and spring, followed by long seed pods. Plants are cross-pollinated by several species of honeyeater and thornbill, which visit nectaries on the phyllodes and brush against flowers, transferring pollen between them. An understorey plant in eucalyptus forest, it is found from southern New South Wales and the Australian Capital Territory, through Victoria and into southeastern South Australia.
Explorer Thomas Mitchell collected the type specimen, from which George Bentham wrote the species description in 1842. No subspecies are recognised. The bark of A. pycnantha produces more tannin than any other wattle species, resulting in its commercial cultivation for production of this compound. It has been widely grown as an ornamental garden plant and for cut flower production, but has become a weed in South Africa, Tanzania, Italy, Portugal, Sardinia, India, Indonesia, New Zealand, as well as Western Australia, Tasmania and New South Wales. Acacia pycnantha was made the official floral emblem of Australia in 1988, and has been featured on the country's postal stamps. (Full article...)- Corona Australis is a constellation in the Southern Celestial Hemisphere. Its Latin name means "southern crown", and it is the southern counterpart of Corona Borealis, the northern crown. It is one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. The Ancient Greeks saw Corona Australis as a wreath rather than a crown and associated it with Sagittarius or Centaurus. Other cultures have likened the pattern to a turtle, ostrich nest, a tent, or even a hut belonging to a rock hyrax.
Although fainter than its northern counterpart, the oval- or horseshoe-shaped pattern of its brighter stars renders it distinctive. Alpha and Beta Coronae Australis are the two brightest stars with an apparent magnitude of around 4.1. Epsilon Coronae Australis is the brightest example of a W Ursae Majoris variable in the southern sky. Lying alongside the Milky Way, Corona Australis contains one of the closest star-forming regions to the Solar System—a dusty dark nebula known as the Corona Australis Molecular Cloud, lying about 430 light years away. Within it are stars at the earliest stages of their lifespan. The variable stars R and TY Coronae Australis light up parts of the nebula, which varies in brightness accordingly. (Full article...)
Rhodocene is a chemical compound with the formula [Rh(C5H5)2]. Each molecule contains an atom of rhodium bound between two planar aromatic systems of five carbon atoms known as cyclopentadienyl rings in a sandwich arrangement. It is an organometallic compound as it has (haptic) covalent rhodium–carbon bonds. The [Rh(C5H5)2] radical is found above 150 °C or when trapped by cooling to liquid nitrogen temperatures (−196 °C). At room temperature, pairs of these radicals join via their cyclopentadienyl rings to form a dimer, a yellow solid.
The history of organometallic chemistry includes the 19th-century discoveries of Zeise's salt and nickel tetracarbonyl. These compounds posed a challenge to chemists as the compounds did not fit with existing chemical bonding models. A further challenge arose with the discovery of ferrocene, the iron analogue of rhodocene and the first of the class of compounds now known as metallocenes. Ferrocene was found to be unusually chemically stable, as were analogous chemical structures including rhodocenium, the unipositive cation of rhodocene and its cobalt and iridium counterparts. The study of organometallic species including these ultimately led to the development of new bonding models that explained their formation and stability. Work on sandwich compounds, including the rhodocenium-rhodocene system, earned Geoffrey Wilkinson and Ernst Otto Fischer the 1973 Nobel Prize for Chemistry. (Full article...)- Cartoon representation of a proteasome. Its active sites are sheltered inside the tube (blue). The caps (red; in this case, 11S regulatory particles) on the ends regulate entry into the destruction chamber, where the protein is degraded.
Proteasomes are protein complexes which degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks peptide bonds. Enzymes that help such reactions are called proteases.
Proteasomes are part of a major mechanism by which cells regulate the concentration of particular proteins and degrade misfolded proteins. Proteins are tagged for degradation with a small protein called ubiquitin. The tagging reaction is catalyzed by enzymes called ubiquitin ligases. Once a protein is tagged with a single ubiquitin molecule, this is a signal to other ligases to attach additional ubiquitin molecules. The result is a polyubiquitin chain that is bound by the proteasome, allowing it to degrade the tagged protein. The degradation process yields peptides of about seven to eight amino acids long, which can then be further degraded into shorter amino acid sequences and used in synthesizing new proteins. (Full article...) - G. tibicen hypoleuca, Tasmania
The Australian magpie (Gymnorhina tibicen) is a medium-sized black and white passerine bird native to Australia and southern New Guinea. Although once considered to be three separate species, it is now considered to be one, with nine recognised subspecies. A member of the Artamidae, the Australian magpie is placed in its own genus Gymnorhina and is most closely related to the black butcherbird (Melloria quoyi). It is not, however, closely related to the European magpie, which is a corvid.
The adult Australian magpie is a fairly robust bird ranging from 37 to 43 cm (14.5 to 17 in) in length, with distinctive black and white plumage, gold brown eyes and a solid wedge-shaped bluish-white and black bill. The male and female are similar in appearance, and can be distinguished by differences in back markings. The male has pure white feathers on the back of the head and the female has white blending to grey feathers on the back of the head. With its long legs, the Australian magpie walks rather than waddles or hops and spends much time on the ground. (Full article...) - Edward Adrian Wilson, Robert Falcon Scott, Lawrence Oates, Henry Robertson Bowers and Edgar Evans at the South Pole
The Terra Nova Expedition, officially the British Antarctic Expedition, was an expedition to Antarctica which took place between 1910 and 1913. Led by Captain Robert Falcon Scott, the expedition had various scientific and geographical objectives. Scott wished to continue the scientific work that he had begun when leading the Discovery Expedition from 1901 to 1904, and wanted to be the first to reach the geographic South Pole. He and four companions attained the pole on 17 January 1912, where they found that a Norwegian team led by Roald Amundsen had preceded them by 34 days. Scott's entire party of five died on the return journey from the pole; some of their bodies, journals, and photographs were found by a search party eight months later.
The expedition, named after its supply ship, was a private venture financed by public contributions and a government grant. It had further backing from the Admiralty, which released experienced seamen to the expedition, and from the Royal Geographical Society (RGS). The expedition's team of scientists carried out a comprehensive scientific programme, while other parties explored Victoria Land and the Western Mountains. An attempted landing and exploration of King Edward VII Land was unsuccessful. A journey to Cape Crozier in June and July 1911 was the first extended sledging journey in the depths of the Antarctic winter. (Full article...)
Grevillea juniperina, commonly known as juniper- or juniper-leaf grevillea or prickly spider-flower, is a plant of the family Proteaceae native to eastern New South Wales and south-eastern Queensland in Australia. Scottish botanist Robert Brown described the species in 1810, and seven subspecies are recognised. One subspecies, G. j. juniperina, is restricted to Western Sydney and environs and is threatened by loss of habitat and housing development.
A small prickly leaved shrub between 0.2 and 3 m (8 in to 10 ft) high, G. juniperina grows generally on clay-based or alluvial soils in eucalypt woodland. The flower heads, known as inflorescences, appear from winter to early summer and are red, orange or yellow. Birds visit and pollinate the flowers. Grevillea juniperina plants are killed by bushfire, regenerating afterwards from seed. Grevillea juniperina adapts readily to cultivation and has been important in horticulture as it is the parent of many popular garden hybrids. (Full article...)
Marjory Stoneman Douglas (April 7, 1890 – May 14, 1998) was an American journalist, author, women's suffrage advocate, and conservationist known for her staunch defense of the Everglades against efforts to drain it and reclaim land for development. Moving to Miami as a young woman to work for The Miami Herald, she became a freelance writer, producing over one hundred short stories that were published in popular magazines. Her most influential work was the book The Everglades: River of Grass (1947), which redefined the popular conception of the Everglades as a treasured river instead of a worthless swamp. Its impact has been compared to that of Rachel Carson's influential book Silent Spring (1962). Her books, stories, and journalism career brought her influence in Miami, enabling her to advance her causes.
As a young woman, Douglas was outspoken and politically conscious of the women's suffrage and civil rights movements. She was called upon to take a central role in the protection of the Everglades when she was 79 years old. For the remaining 29 years of her life she was "a relentless reporter and fearless crusader" for the natural preservation and restoration of South Florida. Her tireless efforts earned her several variations of the nickname "Grande Dame of the Everglades" as well as the hostility of agricultural and business interests looking to benefit from land development in Florida. She received numerous awards, including the Presidential Medal of Freedom, and was inducted into several halls of fame. (Full article...)
Isidor Isaac Rabi (/ˈrɑːbi/; born Israel Isaac Rabi, July 29, 1898 – January 11, 1988) was an American physicist who won the Nobel Prize in Physics in 1944 for his discovery of nuclear magnetic resonance, which is used in magnetic resonance imaging. He was also one of the first scientists in the United States to work on the cavity magnetron, which is used in microwave radar and microwave ovens.
Born into a traditional Polish-Jewish family in Rymanów, Galicia, Rabi came to the United States as a baby and was raised in New York's Lower East Side. He entered Cornell University as an electrical engineering student in 1916, but soon switched to chemistry. Later, he became interested in physics. He continued his studies at Columbia University, where he was awarded his doctorate for a thesis on the magnetic susceptibility of certain crystals. In 1927, he headed for Europe, where he met and worked with many of the finest physicists of the time. (Full article...)
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| Предоставлено: НАСА / Лаборатория реактивного движения / Университет Аризоны. |
Модели облака на Юпитере это видимая система цветных облаков вершин в атмосфере планеты Юпитер , отличается своей стабильностью. Астрономы дали названия частям этого узора, используя слово зона для светлых полос и пояс для темных полос на разных широтах . Узор и интенсивность его поясов и зон, как известно, изменчивы, часто заметно меняясь от одного противостояния к другому.
Нормальный рисунок полос и зон иногда нарушается на какое-то время в результате событий, которые астрономы называют «возмущениями». Наиболее долгоживущее нарушение в истории человечества было «Южная тропическая Помехой» (STropD) с 1901 до 1939 года, обнаружил Перси Б. Моулзуорт на 28 февраля 1901. Он создал затемненную функцию в диапазоне долгот в нормальном освещении Южного Тропический пояс.
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Гаусс Произношение ( помощь · информация ) (30 апреля 1777 - 23 февраля 1855) был немецкий математик и ученый глубокого гения , которыезначительный вклад во многих областях,том числе теории чисел , анализа , дифференциальной геометрии , геодезии , магнетизма , астрономии и оптики . Иногда известный как «князь математиков» и «величайший математик со времен античности», Гаусс оказал заметное влияние во многих областях математики и науки и считается одним из самых влиятельных математиков в истории.
Гаусс завершил Disquisitiones Arithmeticae , свой magnum opus в возрасте двадцати одного года (1798 г.), хотя он не будет опубликован до 1801 г. Эта работа была фундаментальной для консолидации теории чисел как дисциплины и сформировала эту область до наших дней.
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Вы знали...
- ... что лазерная арфа (на фото) - это электронный музыкальный инструмент, состоящий из нескольких лазерных лучей, которые блокируются для воспроизведения звука?
- ... что Terminonatator ponteixensis является типом и только вид описан для Terminonatator , в роде из elasmosaurid плезиозавра из позднего мела в Саскачеване , Канада ?
- ... некротический фасциит - это редкая инфекция подкожных тканей, которая приводит к некрозу плоти?
- ... Напалм-Б , использовавшийся во Вьетнамской войне , был синтезирован всего из трех ингредиентов: полистирола , бензина и бензола ?
- ... Наушники с активным шумоподавлением , использовать схемы для создания разрушительных волновых помех для ослабления фонового звука?
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