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1954 In Science
The year 1954 in science and technology involved some significant events, listed below. Astronomy * November 30 – In Sylacauga, Alabama, an 8.5 pound sulfide meteorite crashes through a roof and hits Mrs. Elizabeth Hodges in her living room after bouncing off her radio, giving her a bad bruise; the first known modern case of a human being hit by a space rock. Biology * January 10 – Last confirmed specimen of a Caspian tiger is killed, in the valley of the Sumbar River in the Kopet Dag Mountains of Turkmenistan. * Daniel I. Arnon demonstrates in the laboratory the chemical function of photosynthesis in chloroplasts. * Heinz Sielmann makes the pioneering nature documentary about woodpeckers, ''Zimmerleute des Waldes'' ("Carpenters of the forest"). * Eduard Paul Tratz and Heinz Heck propose the species name ''bonobo'' for what was previously known as the pygmy chimpanzee. Chemistry * Publication of the first analysis of the three-dimensional molecular structure of vitamin B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sylacauga, Alabama
Sylacauga is a city in Talladega County, Alabama, United States. At the 2020 census, the population was 12,578. Sylacauga is known for its fine white marble bedrock. This was discovered shortly after settlers moved into the area and has been quarried ever since. The marble industry was the first recorded industry in the Sylacauga area. Sylacauga is the site of the first documented case of an object from outer space hitting a person. On November 30, 1954, a piece of what became known as the Hodges Fragment from the Sylacauga Meteorite crashed through the roof of an Oak Grove house, bounced off a radio, and badly bruised Ann Hodges, who was taking an afternoon nap. Sylacauga is on the 2010 list of "100 Best Communities for Young People" by America's Promise Alliance. History The first historical account of the area comes from de Soto's chroniclers as his expedition traveled south along the east bank of the Coosa River in 1540, encountering the town of Talisi at the edge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin B12
Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. It is one of eight B vitamins. It is required by animals, which use it as a cofactor in DNA synthesis, in both fatty acid and amino acid metabolism. It is important in the normal functioning of the nervous system via its role in the synthesis of myelin, and in the circulatory system in the maturation of red blood cells in the bone marrow. Plants do not need cobalamin and carry out the reactions with enzymes that are not dependent on it. Vitamin B12 is the most chemically complex of all vitamins, and for humans, the only vitamin that must be sourced from animal-derived foods or from supplements. Only some archaea and bacteria can synthesize vitamin B12. Most people in developed countries get enough B12 from the consumption of meat or foods with animal sources. Foods containing vitamin B12 include meat, clams, liver, fish, poultry, eggs, and dairy products. Many breakfast cereals are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arkansas
Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the Osage language, a Dhegiha Siouan language, and referred to their relatives, the Quapaw people. The state's diverse geography ranges from the mountainous regions of the Ozark and Ouachita Mountains, which make up the U.S. Interior Highlands, to the densely forested land in the south known as the Arkansas Timberlands, to the eastern lowlands along the Mississippi River and the Arkansas Delta. Arkansas is the 29th largest by area and the 34th most populous state, with a population of just over 3 million at the 2020 census. The capital and most populous city is Little Rock, in the central part of the state, a hub for transportation, business, culture, and government. The northwestern corner of the state, including the Fayetteville–Springdaleâ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnet Cove Igneous Complex
The Magnet Cove igneous complex is a small alkalic ring complex lying to the west of the town of Magnet Cove in Hot Spring County, Arkansas.Geology of Titanium-Mineral Deposits, Eric R. Force, Geological Society of America, 1991,Google Books/ref> It and the adjacent town are so named due to the existence of magnetite and the terrain being a cove, a basin-shaped valley. The complex is of Mesozoic age, intruded into Paleozoic sediments. Mapping was conducted by the geologists Erickson and Blade in 1963. Units within the complex include carbonatite, nepheline syenite, phonolite, and ijolite. In addition to the magnetite which forms both massive lodestone and crystals, the complex is strewn with odd and rare minerals, and is the type locality for five mineral species. Over 100 different minerals have been identified from the area. There are many titanium minerals such as rutile, anatase, brookite, and perovskite, as well as some vanadium mineralization. Some rare-earth-bearing m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benstonite
Benstonite is a mineral with formula Ba6Ca6Mg(CO3)13. Discovered in 1954, the mineral was described in 1961 and named after Orlando J. Benston (1901–1966). Description and occurrence Benstonite is translucent and white, pale yellow, or pale yellow-brown in color. The mineral occurs as cleavable masses; cleavage fragments are nearly perfectly rhombohedral in shape. Cleavage faces are up to across and slightly curved. On large specimens, the faces exhibit a mosaic structure similar to that in some specimens of dolomite and siderite. Benstonite fluoresces red or yellow under x-rays and longwave and shortwave ultraviolet. The mineral also exhibits strong red phosphorescence. Benstonite is known to occur in Canada, China, India, Italy, Namibia, Russia, Sweden, and the United States. It occurs in association with alstonite, barite, barytocalcite, calcite, daqingshanite, fluorite, huntite, monazite, phlogopite, pyrite, sphalerite, strontianite, and quartz. Synthesis The mineral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Machine Translation
Machine translation, sometimes referred to by the abbreviation MT (not to be confused with computer-aided translation, machine-aided human translation or interactive translation), is a sub-field of computational linguistics that investigates the use of software to translate text or speech from one language to another. On a basic level, MT performs mechanical substitution of words in one language for words in another, but that alone rarely produces a good translation because recognition of whole phrases and their closest counterparts in the target language is needed. Not all words in one language have equivalent words in another language, and many words have more than one meaning. Solving this problem with corpus statistical and neural techniques is a rapidly growing field that is leading to better translations, handling differences in linguistic typology, translation of idioms, and the isolation of anomalies. Current machine translation software often allows for customizat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transistor Computer
A transistor computer, now often called a second-generation computer, is a computer which uses discrete transistors instead of vacuum tubes. The first generation of electronic computers used vacuum tubes, which generated large amounts of heat, were bulky and unreliable. A second-generation computer, through the late 1950s and 1960s featured circuit boards filled with individual transistors and magnetic core memory. These machines remained the mainstream design into the late 1960s, when integrated circuits started appearing and led to the third-generation computer. History The University of Manchester's experimental Transistor Computer was first operational in November 1953 and it is widely believed to be the first transistor computer to come into operation anywhere in the world. There were two versions of the Transistor Computer, the prototype, operational in 1953, and the full-size version, commissioned in April 1955. The 1953 machine had 92 point-contact transistors and 550 di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell Labs
Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by multinational company Nokia. With headquarters located in Murray Hill, New Jersey, the company operates several laboratories in the United States and around the world. Researchers working at Bell Laboratories are credited with the development of radio astronomy, the transistor, the laser, the photovoltaic cell, the charge-coupled device (CCD), information theory, the Unix operating system, and the programming languages B, C, C++, S, SNOBOL, AWK, AMPL, and others. Nine Nobel Prizes have been awarded for work completed at Bell Laboratories. Bell Labs had its origin in the complex corporate organization of the Bell System telephone conglomerate. In the late 19th century, the laboratory began as the Western Electric Engineering Department, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRADIC
The TRADIC (for TRAnsistor DIgital Computer or TRansistorized Airborne DIgital Computer) was the first transistorized computer in the USA, completed in 1954. The computer was built by Jean Howard Felker of Bell Labs for the United States Air Force while L.C. Brown ("Charlie Brown") was a lead engineer on the project, which started in 1951. The project initially examined the feasibility of constructing a transistorized airborne digital computer. A second application was a transistorized digital computer to be used in a Navy track-while-scan shipboard radar system. Several models were completed: TRADIC Phase One computer, Flyable TRADIC, Leprechaun (using germanium alloy junction transistors in 1956) and XMH-3 TRADIC. TRADIC Phase One was developed to explore the feasibility, in the laboratory, of using transistors in a digital computer that could be used to solve aircraft bombing and navigation problems. Flyable TRADIC was used to establish the feasibility of using an airborne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Wittig
Georg Wittig (; 16 June 1897 – 26 August 1987) was a German chemist who reported a method for synthesis of alkenes from aldehydes and ketones using compounds called phosphonium ylides in the Wittig reaction. He shared the Nobel Prize in Chemistry with Herbert C. Brown in 1979. Biography Wittig was born in Berlin, Germany and shortly after his birth moved with his family to Kassel, where his father was professor at the applied arts high school. He attended school in Kassel and started studying chemistry at the University of Tübingen 1916. He was drafted and became a lieutenant in the cavalry of Hesse-Kassel (or Hesse-Cassel). After being an Allied prisoner of war from 1918 until 1919, Wittig found it hard to restart his chemistry studies owing to overcrowding at the universities. By a direct plea to Karl von Auwers, who was professor for organic chemistry at the University of Marburg at the time, he was able to resume university study and after 3 years was awarded the Ph.D. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wittig Reaction
The Wittig reaction or Wittig olefination is a chemical reaction of an aldehyde or ketone with a triphenyl phosphonium ylide called a Wittig reagent. Wittig reactions are most commonly used to convert aldehydes and ketones to alkenes. Most often, the Wittig reaction is used to introduce a methylene group using methylenetriphenylphosphorane (Ph3P=CH2). Using this reagent, even a sterically hindered ketone such as camphor can be converted to its methylene derivative. Stereochemistry For the reaction with aldehydes, the double bond geometry is readily predicted based on the nature of the ylide. With unstabilised ylides (R3 = alkyl) this results in (''Z'')-alkene product with moderate to high selectivity. With stabilized ylides (R3 = ester or ketone), the (''E'')-alkene is formed with high selectivity. The (''E'')/(''Z'') selectivity is often poor with semistabilized ylides (R3 = aryl). To obtain the (''E'')-alkene for unstabilized ylides, the Schlosser modification of the W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
