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Oak Ridge, Tennessee Unlike the earlier land acquisitions by the Tennessee Valley Authority for Norris Dam—which were still fresh on the minds of many Anderson Countians—the Corps' "declaration of taking" was much more swift and final. Many residents came home to find eviction notices tacked to their doors. Most were g... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee During construction of the magnets, which were required for the process that would separate the uranium at the Y-12 site, a shortage of copper forced the MED to borrow 14,700 tons of silver bullion from the United States Treasury to be used for electrical conductors for the electromagnet coils as a... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee Prefabricated modular homes, apartments, and dormitories, many made from cemesto (bonded cement and asbestos) panels, were quickly erected. Streets were laid out in the manner of a "planned community". The original streets included several main east-to-west roads, namely the Oak Ridge Turnpike, Ten... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee The news of the use of the first atomic bomb against Japan on August 6, 1945, revealed to the people at Oak Ridge what they had been working on. Oak Ridge was developed by the federal government as a segregated community as a requirement by the Southern bloc of Democrats in Congress to authorize fu... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee After the war, all hutments were dismantled, and a colored neighborhood of permanent houses was developed in the Gamble Valley area of Oak Ridge, which during wartime had been occupied by a white trailer community. Oak Ridge elementary education prior to 1954 was totally segregated; it was legally ... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee Robertsville Junior High School, serving the west half of Oak Ridge, was desegregated at the same time as the high school. Elementary schools in other parts of the city and Jefferson Junior High School, serving the east half of the city, were desegregated slowly as African-American families moved i... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee Two of the four major facilities created for the wartime bomb production are still standing today: In 1983, the Department of Energy declassified a report showing that significant amounts of mercury had been released from the Oak Ridge Reservation into the East Fork Poplar Creek between 1950 and 19... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee Its role in the Manhattan Project is preserved in the Manhattan Project National Historical Park (along with sites in Hanford, Washington and Los Alamos, New Mexico), run cooperatively by the National Park Service and the Department of Energy. Immediately northeast of Oak Ridge, the southwestward-f... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee The main section of the city is located in the northeast, where East Fork and Pine Ridge give way to low, scattered hills. Many of the city's residences are located along the relatively steep northeastern slope of Blackoak Ridge. The completion of Melton Hill Dam (along the Clinch near Copper Ridge... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee However, temperatures reaching either or are uncommon, having last occurred February 5, 1996 (the date of the all-time record low for February) and July 1, 2012. Precipitation is high, averaging annually, but reaches a low during late summer. The rainiest calendar day on record is August 10, 1960 w... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee 8% from 25 to 44, 28.9% from 45 to 64, and 19.3% who were 65 years of age or older. The median age was 43.5 years. For every 100 females, there were 89.4 males. For every 100 females age 18 and over, there were 86.3 males. The median income for a household in the city was $48,716, and the median in... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee The Department of Energy's Environmental Management office is conducting an extensive program of decontamination and decommissioning, environmental cleanup, and waste management to remove or stabilize the hazardous residues remaining from decades of government production and research activities. Th... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee Several radioactive waste processing companies, including EnergySolutions, have operations in Oak Ridge. The infrastructure that was new in the 1940s is aging. The once-isolated city is now incorporated into the Knoxville metropolitan area. Oak Ridge is now challenged to blend into the suburban orb... | https://en.wikipedia.org/wiki?curid=151055 |
Oak Ridge, Tennessee Other higher education organizations present in the community, but not offering classes locally, include the Oak Ridge Institute for Science and Education, Oak Ridge Associated Universities, and the University of Tennessee Forestry Stations and Arboretum. Independent schools in the city include the... | https://en.wikipedia.org/wiki?curid=151055 |
Paul-Émile Lecoq de Boisbaudran Paul-Émile Lecoq de Boisbaudran, also called François Lecoq de Boisbaudran (18 April 1838 – 28 May 1912), was a French chemist known for his discoveries of the chemical elements gallium, samarium and dysprosium. He developed methods for separation and purification of the rare earth eleme... | https://en.wikipedia.org/wiki?curid=151434 |
Paul-Émile Lecoq de Boisbaudran He obtained the syllabus of the École Polytechnique, and he studied the books assigned in its courses. In this way, he was self-taught as a scientist. As such, de Boisbaudran is an example of an autodidact. With the support of his family, he assembled a modest chemical laboratory on the ... | https://en.wikipedia.org/wiki?curid=151434 |
Paul-Émile Lecoq de Boisbaudran Lecoq de Boisbaudran made major contributions to the then-new science of spectroscopy, which relates to the interaction of light and matter. He applied spectroscopy to characterize elements, particularly the rare-earth elements. He developed a theoretical framework of spectroscopy, based... | https://en.wikipedia.org/wiki?curid=151434 |
Paul-Émile Lecoq de Boisbaudran In 1885, he also spectroscopically characterized gadolinium in 1885, an element previously discovered in 1880 by J. C. Galissard de Marignac. Lecoq de Boisbaudran discovered samarium in 1879 after first isolating samarium oxide. He identified the presence of a new element by using spectr... | https://en.wikipedia.org/wiki?curid=151434 |
Paul-Émile Lecoq de Boisbaudran Later he prepared 75 grams of gallium using more than 4 tonnes of the crude ore. He confirmed its spectral characteristics, consisting of two spectral lines in the violet portion of the spectrum of the mineral sphalerite. In this way, he ruled out the possibility that the spectral charac... | https://en.wikipedia.org/wiki?curid=151434 |
Paul-Émile Lecoq de Boisbaudran Lecoq de Boisbaudran noted a spectral band in the yellow-green portion of the spectrum, indicative of a new element. In 1886 he succeeded in isolating a purified sample of the source of the new spectral band. He named the element dysprosium, meaning "difficult to obtain" in the Greek lan... | https://en.wikipedia.org/wiki?curid=151434 |
Philosopher's stone The philosopher's stone, more properly philosophers' stone or stone of the philosophers () is a legendary alchemical substance capable of turning base metals such as mercury into gold (, from the Greek χρυσός "khrusos", "gold", and ποιεῖν "poiēin", "to make") or silver. It is also called the elixir ... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone According to Plato, the four elements are derived from a common source or prima materia (first matter), associated with chaos. "Prima materia" is also the name alchemists assign to the starting ingredient for the creation of the philosophers' stone. The importance of this philosophical first matter ... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone The elixir powder came to be regarded as a crucial component of transmutation by later Arab alchemists. In the 11th century, there was a debate among Muslim world chemists on whether the transmutation of substances was possible. A leading opponent was the Persian polymath Avicenna (Ibn Sina), who di... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone Called the "wordless book", it was a collection of 15 illustrations. The equivalent of the philosophers' stone in Buddhism and Hinduism is the "Cintamani". It is also referred to as Paras/Parasmani (Sanskrit: पारसमणि, Hindi: पारस) or Paris (Marathi: परिस). In Mahayana Buddhism, "Chintamani" is held ... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone The seventh century Siddhar Thirumoolar in his classic "Tirumandhiram" explains man's path to immortal divinity. In verse 2709 he declares that the name of God, Shiva is an alchemical vehicle that turns the body into immortal gold. The most commonly mentioned properties are the ability to transmute ... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone Numerous synonyms were used to make oblique reference to the stone, such as "white stone" ("calculus albus", identified with the "calculus candidus" of Revelation 2:17 which was taken as a symbol of the glory of heaven), "vitriol" (as expressed in the backronym "Visita Interiora Terrae Rectificando ... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone The name of "Stone" or "lapis" itself is informed by early Christian allegory, such as Priscillian (4th century), who stated "Unicornis est Deus, nobis petra Christus, nobis lapis angularis Jesus, nobis hominum homo Christus" (One-horned is God, Christ the rock to us, Jesus the cornerstone to us, Ch... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone Alchemical authors sometimes suggest that the stone's descriptors are metaphorical. The appearance is expressed geometrically in Michael Maier's "Atalanta Fugiens". "Make of a man and woman a circle; then a quadrangle; out of this a triangle; make again a circle, and you will have the Stone of the W... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone Though esoteric and exoteric approaches are sometimes mixed, it is clear that some authors "are not concerned with material substances but are employing the language of exoteric alchemy for the sole purpose of expressing theological, philosophical, or mystical beliefs and aspirations". New interpret... | https://en.wikipedia.org/wiki?curid=152176 |
Philosopher's stone Examples include "Harry Potter and the Philosopher's Stone" and "Fullmetal Alchemist". The philosopher's stone is an important motif in Gothic fiction, and originated in William Godwin's 1799 novel "St. Leon". | https://en.wikipedia.org/wiki?curid=152176 |
Nuclide A nuclide (or nucleide, from nucleus, also known as nuclear species) is an atomic species characterized by the specific constitution of its nucleus, i.e., by its number of protons, "Z", its number of neutrons, "N", and its nuclear energy state. The word "nuclide" was proposed by Truman P. Kohman in 1947. Kohman... | https://en.wikipedia.org/wiki?curid=152464 |
Nuclide Since isotope is the older term, it is better known than nuclide, and is still sometimes used in contexts where nuclide might be more appropriate, such as nuclear technology and nuclear medicine. Although the words nuclide and isotope are often used interchangeably, being isotopes is actually only one relation ... | https://en.wikipedia.org/wiki?curid=152464 |
Nuclide An example is the two states of the single isotope shown among the decay schemes. Each of these two states (technetium-99m and technetium-99) qualifies as a different nuclide, illustrating one way that nuclides may differ from isotopes (an isotope may consist of several different nuclides of different excitatio... | https://en.wikipedia.org/wiki?curid=152464 |
Nuclide These are remnants of [[nucleosynthesis]] that occurred in stars before the formation of the [[solar system]]. For example, the isotope (t = ) of [[uranium]] is still fairly abundant in nature, but the shorter-lived isotope (t = ) is 138 times rarer. About 34 of these nuclides have been discovered (see [[List o... | https://en.wikipedia.org/wiki?curid=152464 |
Nuclide An example of nuclides made by nuclear reactions, are cosmogenic ([[radiocarbon]]) that is made by [[cosmic ray]] bombardment of other elements, and nucleogenic which is still being created by neutron bombardment of natural as a result of natural fission in uranium ores. Cosmogenic nuclides may be either stable... | https://en.wikipedia.org/wiki?curid=152464 |
Nuclide Because protons are positively charged, they repel each other. Neutrons, which are electrically neutral, stabilize the nucleus in two ways. Their copresence pushes protons slightly apart, reducing the electrostatic repulsion between the protons, and they exert the attractive nuclear force on each other and on p... | https://en.wikipedia.org/wiki?curid=152464 |
Nuclide This remarkable difference of nuclear binding energy between neighbouring nuclei, especially of odd-"A" [[isobar (nuclide)|isobars]], has important consequences: unstable isotopes with a nonoptimal number of neutrons or protons decay by [[beta decay]] (including positron decay), [[electron capture]] or other ex... | https://en.wikipedia.org/wiki?curid=152464 |
Eutectic system A eutectic system ( ) from the Greek "εύ" (eu = well) and "τήξις" (tēxis = melting) is a homogeneous mixture of substances that melts or solidifies at a single temperature that is lower than the melting point of any of the constituents. The eutectic temperature is the lowest possible melting temperature... | https://en.wikipedia.org/wiki?curid=152969 |
Eutectic system The eutectic solidification is defined as follows: This type of reaction is an invariant reaction, because it is in thermal equilibrium; another way to define this is the change in Gibbs free energy equals zero. Tangibly, this means the liquid and two solid solutions all coexist at the same time and are... | https://en.wikipedia.org/wiki?curid=152969 |
Eutectic system Eutectic alloys have two or more materials and have a eutectic composition. When a non-eutectic alloy solidifies, its components solidify at different temperatures, exhibiting a plastic melting range. Conversely, when a well-mixed, eutectic alloy melts, it does so at a single, sharp temperature. The var... | https://en.wikipedia.org/wiki?curid=152969 |
Eutectic system Since the solid product forms at the interface between the two reactants, it can form a diffusion barrier and generally causes such reactions to proceed much more slowly than eutectic or eutectoid transformations. Because of this, when a peritectic composition solidifies it does not show the lamellar st... | https://en.wikipedia.org/wiki?curid=152969 |
Eutectic system The Gibbs free energy "G" depends on its own differential: Thus, the "G"/"T" derivative at constant pressure is calculated by the following equation: The chemical potential formula_5 is calculated if we assume that the activity is equal to the concentration: At the equilibrium, formula_7, thus formula_8... | https://en.wikipedia.org/wiki?curid=152969 |
Periodic table (electron configurations) See list of sources at Electron configurations of the elements (data page). | https://en.wikipedia.org/wiki?curid=153197 |
Friedrich Ernst Dorn (27 July 1848 – 16 December 1916) was a German physicist who was the first to discover that a radioactive substance, later named radon, is emitted from radium. Dorn was born in Guttstadt (Dobre Miasto), Province of Prussia (nowadays Warmia in Poland), and died in Halle, Province of Saxony. He was e... | https://en.wikipedia.org/wiki?curid=153260 |
Friedrich Ernst Dorn Dorn called the radioactive gaseous product from radium simply "emanation", but in 1904 Rutherford introduced the name "radium emanation" for the same material. Ramsay later suggested "niton", from the Latin word "nitens" meaning "shining". In 1923 the name was again changed, this time to radon by ... | https://en.wikipedia.org/wiki?curid=153260 |
Robert Whytlaw-Gray Robert H. Whytlaw-Gray, FRS (1877 – 1958) was an English chemist, born in London. He studied at the University of Glasgow and University College London and was Professor of Chemistry at the University of Leeds. He and William Ramsay isolated radon and studied its physical properties (density, weight... | https://en.wikipedia.org/wiki?curid=153262 |
Plastid The plastid (Greek: πλαστός; plastós: formed, molded – plural plastids) is a membrane-bound organelle found in the cells of plants, algae, and some other eukaryotic organisms. They are considered endosymbiotic Cyanobacteria, related to the Gloeomargarita. Plastids were discovered and named by Ernst Haeckel, but... | https://en.wikipedia.org/wiki?curid=153522 |
Plastid In plants, undifferentiated plastids (proplastids) may differentiate into several forms, depending upon which function they perform in the cell. They may develop into any of the following variants: Depending on their morphology and function, plastids have the ability to differentiate, or redifferentiate, betwee... | https://en.wikipedia.org/wiki?curid=153522 |
Plastid The proplastid contains a single nucleoid located in the centre of the plastid. The developing plastid has many nucleoids, localized at the periphery of the plastid, bound to the inner envelope membrane. During the development of proplastids to chloroplasts, and when plastids convert from one type to another, n... | https://en.wikipedia.org/wiki?curid=153522 |
Plastid Some scientists argue that plastid genome loss is unlikely since even non-photosynthetic plastids contain genes necessary to complete various biosynthetic pathways, such as heme biosynthesis. In algae, the term leucoplast is used for all unpigmented plastids. Their function differs from the leucoplasts of plant... | https://en.wikipedia.org/wiki?curid=153522 |
Plastid In interspecific hybridisations, however, the inheritance of plastids appears to be more erratic. Although plastids inherit mainly maternally in interspecific hybridisations, there are many reports of hybrids of flowering plants that contain plastids of the father. Approximately 20% of angiosperms, including al... | https://en.wikipedia.org/wiki?curid=153522 |
Plastid The plastids differ both in their pigmentation and in their ultrastructure. For example, chloroplasts in plants and green algae have lost all phycobilisomes, the light harvesting complexes found in cyanobacteria, red algae and glaucophytes, but instead contain stroma and grana thylakoids. The glaucocystophycean... | https://en.wikipedia.org/wiki?curid=153522 |
Plastid ), toxoplasmosis ("Toxoplasma gondii"), and many other human or animal diseases also harbor a complex plastid (although this organelle has been lost in some apicomplexans, such as "Cryptosporidium parvum", which causes cryptosporidiosis). The 'apicoplast' is no longer capable of photosynthesis, but is an essent... | https://en.wikipedia.org/wiki?curid=153522 |
Crystal optics is the branch of optics that describes the behaviour of light in "anisotropic media", that is, media (such as crystals) in which light behaves differently depending on which direction the light is propagating. The index of refraction depends on both composition and crystal structure and can be calculated... | https://en.wikipedia.org/wiki?curid=153783 |
Crystal optics The value 1+χ is called the "relative permittivity" of the medium, and is related to the refractive index "n", for non-magnetic media, by In an anisotropic medium, such as a crystal, the polarisation field P is not necessarily aligned with the electric field of the light E. In a physical picture, this ca... | https://en.wikipedia.org/wiki?curid=153783 |
Crystal optics Consider a light wave propagating along the z principal axis polarised such the electric field of the wave is parallel to the x-axis. The wave experiences a susceptibility χ and a permittivity ε. The refractive index is thus: For a wave polarised in the y direction: Thus these waves will see two differen... | https://en.wikipedia.org/wiki?curid=153783 |
Crystal optics In response to a magnetic field, some materials can have a dielectric tensor that is complex-Hermitian; this is called a gyro-magnetic or magneto-optic effect. In this case, the principal axes are complex-valued vectors, corresponding to elliptically polarized light, and time-reversal symmetry can be bro... | https://en.wikipedia.org/wiki?curid=153783 |
PH meter A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or basicity expressed as pH. The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode, and so the pH meter is sometimes referred to... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter These have tips suitable for piercing semi-solids, have electrode materials compatible with ingredients in food, and are resistant to clogging. Potentiometric pH meters measure the voltage between two electrodes and display the result converted into the corresponding pH value. They comprise a simple electronic... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter This conductor is immersed in an electrolyte solution, typically potassium chloride, which comes into contact with the test solution through a porous ceramic membrane. The display consists of a voltmeter, which displays voltage in units of pH. On immersion of the glass electrode and the reference electrode in ... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter The pH meter is calibrated with solutions of known pH, typically before each use, to ensure accuracy of measurement. To measure the pH of a solution, the electrodes are used as probes, which are dipped into the test solutions and held there sufficiently long for the hydrogen ions in the test solution to equili... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter The silver chloride electrode is most commonly used as a reference electrode in pH meters, although some designs use the saturated calomel electrode. The silver chloride electrode is simple to manufacture and provides high reproducibility. The reference electrode usually consists of a platinum wire that has co... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter For illustration, one maker of laboratory-grade pH gives cleaning instructions for specific contaminants: general cleaning (15-minute soak in a solution of bleach and detergent), salt (hydrochloric acid solution followed by sodium hydroxide and water), grease (detergent or methanol), clogged reference junction... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter Some pH meters provide built-in temperature-coefficient correction, with temperature thermocouples in the electrode probes. The calibration process correlates the voltage produced by the probe (approximately 0.06 volts per pH unit) with the pH scale. Good laboratory practice dictates that, after each measureme... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter The concept of pH was defined in 1909 by S. P. L. Sørensen, and electrodes were used for pH measurement in the 1920s. In October 1934, Arnold Orville Beckman registered the first patent for a complete chemical instrument for the measurement of pH, U.S. Patent No. 2,058,761, for his "acidimeter", later renamed ... | https://en.wikipedia.org/wiki?curid=154242 |
PH meter " Beckman marketed a portable "Pocket pH Meter" as early as 1956, but it did not have a digital read-out. In the 1970s Jenco Electronics of Taiwan designed and manufactured the first portable digital pH meter. This meter was sold under the label of the Cole-Parmer Corporation. Specialized manufacturing is requ... | https://en.wikipedia.org/wiki?curid=154242 |
Turbulence In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between those layers. is commonly observed in everyday phenomena such as ... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence is characterized by the following features: "Turbulent diffusion" is usually described by a turbulent diffusion coefficient. This turbulent diffusion coefficient is defined in a phenomenological sense, by analogy with the molecular diffusivities, but it does not have a true physical meaning, being dependent ... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence Turbulent flows may be viewed as made of an entire hierarchy of eddies over a wide range of length scales and the hierarchy can be described by the energy spectrum that measures the energy in flow velocity fluctuations for each length scale (wavenumber). The scales in the energy cascade are generally uncontr... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence According to an apocryphal story, Werner Heisenberg was asked what he would ask God, given the opportunity. His reply was: "When I meet God, I am going to ask him two questions: Why relativity? And why turbulence? I really believe he will have an answer for the first." A similar witticism has been attributed... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence The Reynolds number quantifies the relative importance of these two types of forces for given flow conditions, and is a guide to when turbulent flow will occur in a particular situation. This ability to predict the onset of turbulent flow is an important design tool for equipment such as piping systems or ai... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence The transition occurs if the size of the object is gradually increased, or the viscosity of the fluid is decreased, or if the density of the fluid is increased. When flow is turbulent, particles exhibit additional transverse motion which enhances the rate of energy and momentum exchange between them thus inc... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence Richardson's notion of turbulence was that a turbulent flow is composed by "eddies" of different sizes. The sizes define a characteristic length scale for the eddies, which are also characterized by flow velocity scales and time scales (turnover time) dependent on the length scale. The large eddies are unsta... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence Kolmogorov's idea was that in the Richardson's energy cascade this geometrical and directional information is lost, while the scale is reduced, so that the statistics of the small scales has a universal character: they are the same for all turbulent flows when the Reynolds number is sufficiently high. Thus, ... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence Since eddies in this range are much larger than the dissipative eddies that exist at Kolmogorov scales, kinetic energy is essentially not dissipated in this range, and it is merely transferred to smaller scales until viscous effects become important as the order of the Kolmogorov scale is approached. Within ... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence Therefore, by dimensional analysis, the only possible form for the energy spectrum function according with the third Kolmogorov's hypothesis is where would be a universal constant. This is one of the most famous results of Kolmogorov 1941 theory, and considerable experimental evidence has accumulated that su... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence From this fact, and other results of Kolmogorov 1941 theory, it follows that the statistical moments of the flow velocity increments (known as "structure functions" in turbulence) should scale as where the brackets denote the statistical average, and the would be universal constants. There is considerable ev... | https://en.wikipedia.org/wiki?curid=154664 |
Turbulence This is an important area of research in this field, and a major goal of the modern theory of turbulence is to understand what is really universal in the inertial range. | https://en.wikipedia.org/wiki?curid=154664 |
Vortex In fluid dynamics, a vortex (plural vortices/vortexes) is a region in a fluid in which the flow revolves around an axis line, which may be straight or curved. Vortices form in stirred fluids, and may be observed in smoke rings, whirlpools in the wake of a boat, and the winds surrounding a tropical cyclone, torna... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex The direction of the vorticity vector is defined to be the direction of the axis of rotation of this imaginary ball (according to the right-hand rule) while its length is twice the ball's angular velocity. Mathematically, the vorticity is defined as the curl (or rotational) of the velocity field of the fluid, us... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex The angular momentum per unit mass relative to the vortex axis is therefore constant, formula_15. However, the ideal irrotational vortex flow is not physically realizable, since it would imply that the particle speed (and hence the force needed to keep particles in their circular paths) would grow without bound ... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex In this situation, the rigid rotating enclosure provides an extra force, namely an extra pressure gradient in the water, directed inwards, that prevents evolution of the rigid-body flow to the irrotational state. In a stationary vortex, the typical streamline (a line that is everywhere tangent to the flow veloci... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex One end of the vortex line is attached to the engine, while the other end usually stretches out and bends until it reaches the ground. When vortices are made visible by smoke or ink trails, they may seem to have spiral pathlines or streamlines. However, this appearance is often an illusion and the fluid particle... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex The free surface (if present) dips sharply near the axis line, with depth inversely proportional to . The shape formed by the free surface is called a hyperboloid, or "Gabriel's Horn" (by Evangelista Torricelli). The core of a vortex in air is sometimes visible because water vapor condenses as the low pressure o... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex In that case the streamlines and pathlines are not closed curves but spirals or helices, respectively. This is the case in tornadoes and in drain whirlpools. A vortex with helical streamlines is said to be solenoidal. As long as the effects of viscosity and diffusion are negligible, the fluid in a moving vortex ... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex Vortices contain substantial energy in the circular motion of the fluid. In an ideal fluid this energy can never be dissipated and the vortex would persist forever. However, real fluids exhibit viscosity and this dissipates energy very slowly from the core of the vortex. It is only through dissipation of a vorte... | https://en.wikipedia.org/wiki?curid=154665 |
Vortex When two or more vortices are close together they can merge to make a vortex. Vortices also hold energy in its rotation of the fluid. If the energy is never removed, it would consist of circular motion forever. | https://en.wikipedia.org/wiki?curid=154665 |
Hydrogen sulfide is the chemical compound with the formula . It is a colorless chalcogen hydride gas with the characteristic foul odor of rotten eggs. It is very poisonous, corrosive, and flammable. is often produced from the microbial breakdown of organic matter in the absence of oxygen gas, such as in swamps and sewe... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide 1 mol/litre solutions at 18 °C), giving the hydrosulfide ion (also written ). and its solutions are colorless. When exposed to air, it slowly oxidizes to form elemental sulfur, which is not soluble in water. The sulfide anion is not formed in aqueous solution. reacts with metal ions to form metal sulfi... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide sulfur-reducing) bacteria generate usable energy under low-oxygen conditions by using sulfates (resp. elemental sulfur) to oxidize organic compounds or hydrogen; this produces hydrogen sulfide as a waste product. A standard lab preparation is to treat ferrous sulfide with a strong acid in a Kipp genera... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide These enzymes have been identified in a breadth of biological cells and tissues, and their activity has been observed to be induced by a number of disease states. It is becoming increasingly clear that is an important mediator of a wide range of cell functions in health and in disease. CBS and CSE are ... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide Reversibly sodium sulfide in the presence of acids turns into hydrosulfides and hydrogen sulfide; this supplies hydrosulfides in organic solutions and is utilized in the production of thiophenol. For well over a century hydrogen sulfide was important in analytical chemistry in the qualitative inorganic... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide When the cell is stressed with disease, enzymes are drawn into the cell to produce small amounts of hydrogen sulfide. This study could have further implications on preventing strokes, heart disease and arthritis. A suspended animation-like state has been induced in rodents with the use of hydrogen sulf... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide Other anthropogenic sources of hydrogen sulfide include coke ovens, paper mills (using the Kraft process), tanneries and sewerage. arises from virtually anywhere where elemental sulfur comes in contact with organic material, especially at high temperatures. Depending on environmental conditions, it is ... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide If there is a source of sulfate bearing material, such as plasterboard or natural gypsum (calcium sulphate dihydrate), under anaerobic conditions sulfate reducing bacteria converts this to hydrogen sulfide. These bacteria cannot survive in air but the moist, warm, anaerobic conditions of buried waste t... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide Being heavier than air, it tends to accumulate at the bottom of poorly ventilated spaces. Although very pungent at first, it quickly deadens the sense of smell (which smells like rotten egg(s)), so victims may be unaware of its presence until it is too late. For safe handling procedures, a hydrogen sul... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide Treatment involves immediate inhalation of amyl nitrite, injections of sodium nitrite, or administration of 4-dimethylaminophenol in combination with inhalation of pure oxygen, administration of bronchodilators to overcome eventual bronchospasm, and in some cases hyperbaric oxygen therapy (HBOT). HBOT ... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide It was not considered to be an ideal war gas, but, while other gases were in short supply, it was used on two occasions in 1916. In 1975, a hydrogen sulfide release from an oil drilling operation in Denver City, Texas, killed nine people and caused the state legislature to focus on the deadly hazards o... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide A valve to a pipe that carried chicken manure, straw and gypsum to the compost fuel for the mushroom growing operation became clogged, and as workers unclogged the valve in a confined space without proper ventilation the hydrogen sulfide that had built up due to anaerobic decomposition of the material ... | https://en.wikipedia.org/wiki?curid=154738 |
Hydrogen sulfide Their deaths remained unexplained as the medical examiner waited for results of toxicology tests on the victims, until urine tests revealed that hydrogen sulfide was the cause of death. A report from the Orange-Osceola Medical Examiner's Office indicated that toxic fumes came from the Porsche's starter... | https://en.wikipedia.org/wiki?curid=154738 |
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