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Nitrogen-15 nuclear magnetic resonance spectroscopy ( nitrogen-15 NMR spectroscopy , or just simply 15 N NMR ) is a version of nuclear magnetic resonance spectroscopy that examines samples containing the 15 N nucleus. [ 1 ] [ 2 ] 15 N NMR differs in several ways from the more common 13 C and 1 H NMR. To circumvent the ... | https://en.wikipedia.org/wiki/Nitrogen-15_nuclear_magnetic_resonance_spectroscopy |
The nitrogen-vacancy center ( N-V center or NV center ) is one of numerous photoluminescent point defects in diamond . Its most explored and useful properties include its spin-dependent photoluminescence (which enables measurement of the electronic spin state using optically detected magnetic resonance ), and its relat... | https://en.wikipedia.org/wiki/Nitrogen-vacancy_center |
Nitrogen assimilation is the formation of organic nitrogen compounds like amino acids from inorganic nitrogen compounds present in the environment. Organisms like plants , fungi and certain bacteria that can fix nitrogen gas (N 2 ) depend on the ability to assimilate nitrate or ammonia for their needs. Other organisms... | https://en.wikipedia.org/wiki/Nitrogen_assimilation |
Nitrogen difluoride , also known as difluoroamino, is a reactive radical molecule with formula N F 2 . This small molecule is in equilibrium with its dimer tetrafluorohydrazine . [ 2 ]
As the temperature increases the proportion of NF 2 increases. [ 3 ]
The molecule is unusual in that it has an odd number of electron... | https://en.wikipedia.org/wiki/Nitrogen_difluoride |
Dinitrogen tetroxide Dinitrogen trioxide Nitric oxide Nitrous oxide
Nitrogen dioxide is a chemical compound with the formula NO 2 . One of several nitrogen oxides , nitrogen dioxide is a reddish-brown gas. It is a paramagnetic , bent molecule with C 2v point group symmetry . Industrially, NO 2 is an intermediate in t... | https://en.wikipedia.org/wiki/Nitrogen_dioxide |
Nitrogen dioxide poisoning is the illness resulting from the toxic effect of nitrogen dioxide ( NO 2 ). It usually occurs after the inhalation of the gas beyond the threshold limit value . [ 1 ] Nitrogen dioxide is reddish-brown with a very harsh smell at high concentrations, at lower concentrations it is colorless but... | https://en.wikipedia.org/wiki/Nitrogen_dioxide_poisoning |
Nitrogen fixation is a chemical process by which molecular dinitrogen ( N 2 ) is converted into ammonia ( NH 3 ). [ 1 ] It occurs both biologically and abiologically in chemical industries . Biological nitrogen fixation or diazotrophy is catalyzed by enzymes called nitrogenases . [ 2 ] These enzyme complexes are encod... | https://en.wikipedia.org/wiki/Nitrogen_fixation |
A nitrogen fixation package is a piece of research equipment for studying nitrogen fixation in plants. One product of this kind, the Q-Box NF1LP made by Qubit Systems, operates by measuring the hydrogen (H 2 ) given off in the nitrogen-fixing chemical reaction enabled by nitrogenase enzymes.
Nitrogen is produced by ba... | https://en.wikipedia.org/wiki/Nitrogen_fixation_package |
Nitrogen generators and stations are stationary or mobile air-to- nitrogen production complexes.
The adsorption gas separation process in nitrogen generators is based on the phenomenon of fixing various gas mixture components by a solid substance called an adsorbent . This phenomenon is brought about by the gas and ad... | https://en.wikipedia.org/wiki/Nitrogen_generator |
In chemistry , pyramidal inversion (also umbrella inversion ) is a fluxional process in compounds with a pyramidal molecule, such as ammonia (NH 3 ) "turns inside out". [ 1 ] [ 2 ] It is a rapid oscillation of the atom and substituents, the molecule or ion passing through a planar transition state . [ 3 ] For a compoun... | https://en.wikipedia.org/wiki/Nitrogen_inversion |
Fish sauce is a liquid condiment made from fish or krill that have been coated in salt and fermented for up to two years. [ 1 ] [ 2 ] : 234 It is used as a staple seasoning in East Asian cuisine and Southeast Asian cuisine , particularly Myanmar , Cambodia , Laos , Philippines , Thailand , and Vietnam . Some garum -rel... | https://en.wikipedia.org/wiki/Nitrogen_level_(fish_sauce) |
Nitrogen monofluoride (fluoroimidogen) is a metastable species that has been observed in laser studies. It is isoelectronic with O 2 . Like boron monofluoride , it is an instance of the rare multiply-bonded fluorine atom. [ 1 ] [ 2 ] It is unstable with respect to its formal dimer, dinitrogen difluoride , as well as ... | https://en.wikipedia.org/wiki/Nitrogen_monofluoride |
Nitrogen nutrition in the arbuscular mycorrhizal system refers to...
Nitrogen is a vital macronutrient for plants, necessary for the biosynthesis of many basic cellular components, such as DNA , RNA and proteins . Nitrogen is obtained by plants through roots from inorganic or organic sources, such as amino acids . [ 1... | https://en.wikipedia.org/wiki/Nitrogen_nutrition_in_the_arbuscular_mycorrhizal_system |
Nitrogen oxide may refer to a binary compound of oxygen and nitrogen , or a mixture of such compounds:
In atmospheric chemistry :
Due to relatively weak N–O bonding, all nitrogen oxides are unstable with respect to N 2 and O 2 , which is the principle behind the catalytic converter , and prevents the oxygen and nitro... | https://en.wikipedia.org/wiki/Nitrogen_oxide |
Nitrogen pentafluoride is a theoretical compound of nitrogen and fluorine with the chemical formula N F 5 . It is hypothesized to exist based on the existence of the pentafluorides of the atoms below nitrogen in the periodic table, such as phosphorus pentafluoride . Theoretical models of the nitrogen pentafluoride mole... | https://en.wikipedia.org/wiki/Nitrogen_pentafluoride |
Nitrogen pentahydride , also known as ammonium hydride is a hypothetical compound with the chemical formula NH 5 . There are two theoretical structures of nitrogen pentahydride. One structure is trigonal bipyramidal molecular geometry type NH 5 molecule. Its nitrogen atom and hydrogen atoms are covalently bounded, and ... | https://en.wikipedia.org/wiki/Nitrogen_pentahydride |
A nitrogen rejection unit (NRU) selectively removes nitrogen from a gas. The name can be applied to any system that removes nitrogen from natural gas .
For high flow-rate applications, typically above 420 thousand cubic metres (15 million cubic feet ) per day at standard pressure , cryogenic processing is the norm. [ ... | https://en.wikipedia.org/wiki/Nitrogen_rejection_unit |
The nitrogen rule states that organic compounds containing exclusively hydrogen , carbon , nitrogen , oxygen , silicon , phosphorus , sulfur , and the halogens either have (1) an odd nominal mass that indicates an odd number of nitrogen atoms are present or (2) an even nominal mass that indicates an even number of nitr... | https://en.wikipedia.org/wiki/Nitrogen_rule |
The nitrogen solubility index (NSI) is a measure of the solubility of the protein in a substance. It is typically used as a quick measure of the functionality of a protein, for example to predict the ability of the protein to stabilise foams, emulsions or gels. [ 1 ] [ 2 ] To determine the NSI, the sample is dried, dis... | https://en.wikipedia.org/wiki/Nitrogen_solubility_index |
Nitrogen trichloride , also known as trichloramine , is the chemical compound with the formula NCl 3 . This yellow, oily, and explosive liquid is most commonly encountered as a product of chemical reactions between ammonia -derivatives and chlorine (for example, in swimming pools ). Alongside monochloramine and dichlor... | https://en.wikipedia.org/wiki/Nitrogen_trichloride |
Nitrogen trifluoride is the inorganic compound with the formula ( NF 3 ). It is a colorless, non- flammable , toxic gas with a slightly musty odor. In contrast with ammonia, it is nonbasic. It finds increasing use within the manufacturing of flat-panel displays , photovoltaics , LEDs and other microelectronics . [ 6 ]... | https://en.wikipedia.org/wiki/Nitrogen_trifluoride |
Nitrogen triiodide is an inorganic compound with the formula N I 3 . It is an extremely sensitive contact explosive : small quantities explode with a loud, sharp snap when touched even lightly, releasing a purple cloud of iodine vapor; it can even be detonated by alpha radiation . NI 3 has a complex structural chemistr... | https://en.wikipedia.org/wiki/Nitrogen_triiodide |
The nitrogen–phosphorus detector ( NPD ) is also known as thermionic specific detector ( TSD ) is a detector commonly used with gas chromatography , in which thermal energy is used to ionize an analyte . [ 1 ] [ 2 ] It is a type of flame thermionic detector (FTD), the other being the alkali flame-ionization detector (A... | https://en.wikipedia.org/wiki/Nitrogen–phosphorus_detector |
Nitroglycerin ( NG ) (alternative spelling nitroglycerine), also known as trinitroglycerol ( TNG ), nitro , glyceryl trinitrate ( GTN ), or 1,2,3-trinitroxypropane , is a dense, colorless or pale yellow, oily, explosive liquid most commonly produced by nitrating glycerol with white fuming nitric acid under conditions a... | https://en.wikipedia.org/wiki/Nitroglycerin |
Nitroguanidine - sometimes abbreviated NGu - is a colorless, crystalline solid that melts at 257 °C and decomposes at 254 °C. Nitroguanidine is an extremely insensitive but powerful high explosive. Wetting it with > 20 wt.-% water effects desensitization from HD 1.1 down to HD 4.1 (flammable solid). [ 2 ] Nitroguanidin... | https://en.wikipedia.org/wiki/Nitroguanidine |
Nitrolic acids are organic compounds with the functional group RC(NO 2 )=NOH. They are prepared by the reaction of nitroalkanes with base and nitrite sources: [ 1 ]
The conversion was first demonstrated by Victor Meyer using nitroethane . [ 2 ] The reaction proceeds via the intermediacy of the nitronate anion.
Most ... | https://en.wikipedia.org/wiki/Nitrolic_acid |
Nitrolite is an older form of powdery high explosive with an ammonium nitrate base, mixed with a smaller amount of TNT and nitroglycerin etc. [ 1 ] [ 2 ] [ 3 ] [ 4 ] It is used for mining, construction as well as military purposes. During World War II it came to be a budget replacement for more expensive TNT. [ 2 ]
Th... | https://en.wikipedia.org/wiki/Nitrolite |
Nitrolysis is a chemical reaction involving cleavage ("lysis") of a chemical bond concomitant with installation of a nitro group (NO 2 ). Typical reagents for effecting this conversion are nitric acid and acetyl nitrate . A commercially important nitrolysis reaction is the conversion of hexamine to nitramide . Nitrol... | https://en.wikipedia.org/wiki/Nitrolysis |
Nitromethane , sometimes shortened to simply "nitro", is an organic compound with the chemical formula CH 3 NO 2 . It is the simplest organic nitro compound . It is a polar liquid commonly used as a solvent in a variety of industrial applications such as in extractions, as a reaction medium, and as a cleaning solvent. ... | https://en.wikipedia.org/wiki/Nitromethane |
This page provides supplementary chemical data on nitromethane .
The handling of this chemical may incur notable safety precautions. MSDS is available from Mallinckrodt Baker. [ 1 ]
Table data obtained from CRC Handbook of Chemistry and Physics 44th ed. | https://en.wikipedia.org/wiki/Nitromethane_(data_page) |
A nitronate ( IUPAC : azinate ) in organic chemistry is an anion with the general structure R 1 R 2 C = N + (− O − ) 2 , containing the =N + (−O − ) 2 functional group , [ 1 ] [ 2 ] where R can be hydrogen , halogen , organyl group or other groups. It is the anion of nitronic acid R 1 R 2 C=N + (−O − )−OH (sometimes al... | https://en.wikipedia.org/wiki/Nitronate |
In organic chemistry , a nitrone is a functional group consisting of an N -oxide of an imine . The general structure is R 1 R 2 C=N + (−O − )(−R 3 ) , where R 3 is not a hydrogen . Their primary application is intermediates in chemical synthesis . A nitrone is a 1,3-dipole used in cycloadditions , and a carbonyl mimic.... | https://en.wikipedia.org/wiki/Nitrone |
The nitronium ion , [ N O 2 ] + , is a cation . It is an onium ion because its nitrogen atom has +1 charge, similar to ammonium ion [NH 4 ] + . It is created by the removal of an electron from the paramagnetic nitrogen dioxide molecule NO 2 , or the protonation of nitric acid HNO 3 (with removal of H 2 O ). [ 2 ]
It i... | https://en.wikipedia.org/wiki/Nitronium_ion |
Nitronium perchlorate , NO 2 ClO 4 , also known as nitryl perchlorate and nitroxyl perchlorate , is an inorganic chemical , the salt of the perchlorate anion and the nitronium cation. It forms colorless monoclinic crystals. It is hygroscopic , and is a strong oxidizing and nitrating agent. It may become hypergolic in c... | https://en.wikipedia.org/wiki/Nitronium_perchlorate |
The nitrophosphate process (also known as the Odda process ) is a method for the industrial production of nitrogen fertilizers invented by Erling Johnson in the municipality of Odda, Norway around 1927.
The process involves acidifying phosphate rock with dilute nitric acid to produce a mixture of phosphoric acid and c... | https://en.wikipedia.org/wiki/Nitrophosphate_process |
Sodium nitroprusside ( SNP ), sold under the brand name Nitropress among others, is a medication used to lower blood pressure . [ 3 ] This may be done if the blood pressure is very high and resulting in symptoms , in certain types of heart failure , and during surgery to decrease bleeding . [ 3 ] It is used by continuo... | https://en.wikipedia.org/wiki/Nitroprusside_reaction |
Nitrosamines (or more formally N -nitrosamines ) are organic compounds produced by industrial processes. [ 1 ]
The chemical structure is R 2 N−N=O , where R is usually an alkyl group . [ 2 ] Nitrosamines have a nitroso group ( NO + ) that are "probable human carcinogens", [ 3 ] bonded to a deprotonated amine . Most ni... | https://en.wikipedia.org/wiki/Nitrosamine |
Nitrosation and nitrosylation are two names for the process of converting organic compounds or metal complexes [ 1 ] into nitroso derivatives, i.e., compounds containing the R−NO functionality. The synonymy arises because the R-NO functionality can be interpreted two different ways, depending on the physico-chemical e... | https://en.wikipedia.org/wiki/Nitrosation_and_nitrosylation |
In organic chemistry , nitroso refers to a functional group in which the nitric oxide ( −N=O ) group is attached to an organic moiety . As such, various nitroso groups can be categorized as C -nitroso compounds (e.g., nitroso alkanes ; R−N=O ), S -nitroso compounds ( nitrosothiols ; RS−N=O ), N -nitroso compounds (e.g.... | https://en.wikipedia.org/wiki/Nitroso |
Nitrosomonas is a genus of Gram-negative bacteria belonging to the class Betaproteobacteria . It is one of the five genera of ammonia-oxidizing bacteria [ 8 ] and, as an obligate chemolithoautotroph , [ 9 ] uses ammonia ( NH 3 {\displaystyle {\ce {NH3}}} ) as an energy source and carbon dioxide ( CO 2 {\displaystyle {\... | https://en.wikipedia.org/wiki/Nitrosomonas |
Nitrososphaera is a mesophilic genus of ammonia-oxidizing Crenarchaeota. [ 1 ] [ 2 ] The first Nitrososphaera organism was discovered in garden soils at the University of Vienna leading to the categorization of a new genus, family, order and class of Archaea. [ 3 ] This genus is contains three distinct species: N. vien... | https://en.wikipedia.org/wiki/Nitrososphaera |
Nitrospinota is a bacterial phylum. Despite only few described species, members of this phylum are major nitrite-oxidizing bacteria in surface waters in oceans. By oxidation of nitrite to nitrate they are important in the process of nitrification in marine environments. [ 3 ]
Although the genus Nitrospina is an aerobi... | https://en.wikipedia.org/wiki/Nitrospinota |
Nitrostarch is a secondary explosive [ 1 ] similar to nitrocellulose . Much like starch , it is made up of two components, nitrated amylose and nitrated amylopectin . Nitrated amylopectin generally has a greater solubility than amylose; however, it is less stable than nitrated amylose. [ 2 ]
The solubility, detonation... | https://en.wikipedia.org/wiki/Nitrostarch |
Nitrosyl- O -hydroxide (molecular formula H O O N ) is an isomer of nitrous acid , which has been experimentally observed in the gas phase. [ 2 ] HOON contains the longest oxygen-oxygen bond thus far observed in any known molecule, measured to be 1.9149 angstroms. There had been speculation about the existence of this ... | https://en.wikipedia.org/wiki/Nitrosyl-O-hydroxide |
Nitrotriazolone ( NTO ) is a heterocyclic semicarbazide -derived high explosive first identified in 1905, but research into its explosive properties was not conducted until the 1980s. [ 2 ] NTO is currently being used by the US Army in munitions, specifically Insensitive munitions replacing those made with legacy explo... | https://en.wikipedia.org/wiki/Nitrotriazolone |
Nitrourea is a strong high explosive compound [ 1 ] synthesized by the nitration of urea or by way of a dehydration reaction of urea nitrate with sulfuric acid at 0 degrees. [ 2 ]
This explosives -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Nitrourea |
Nitrous oxide (dinitrogen oxide or dinitrogen monoxide), commonly known as laughing gas , nitrous , or factitious air , among others, [ 4 ] is a chemical compound , an oxide of nitrogen with the formula N 2 O . At room temperature, it is a colourless non-flammable gas , and has a slightly sweet scent and taste. [ 4 ] A... | https://en.wikipedia.org/wiki/Nitrous_oxide |
Hydrogen oxonitrate(I) Hyponitrous acid monomer Nitronous oxide
Nitroxyl (common name) or azanone (IUPAC name) [ 2 ] is the chemical compound HNO. It is well known in the gas phase. [ 3 ] [ 4 ] Nitroxyl can be formed as a short-lived intermediate in solution. Its conjugate base, NO − , the nitroxide anion, is the redu... | https://en.wikipedia.org/wiki/Nitroxyl |
Nitryl is the nitrogen dioxide (NO 2 ) moiety when it occurs in a larger compound as a univalent fragment. Examples include nitryl fluoride (NO 2 F) and nitryl chloride (NO 2 Cl). [ 1 ]
Like nitrogen dioxide, the nitryl moiety contains a nitrogen atom with two bonds to the two oxygen atoms, and a third bond shared equ... | https://en.wikipedia.org/wiki/Nitryl |
In Indian astronomy, yoga (also called nityayoga ) is a period of time, of varying lengths, during which the sum of the nirayana longitudes of the Sun and the Moon increases by an amount of 13 degrees 20 minutes (or, equivalently, 800 minutes). [ 1 ] While considering the sum, when the sum is 360 degrees or more, then... | https://en.wikipedia.org/wiki/Nityayoga |
In number theory , Niven's constant , named after Ivan Niven , is the largest exponent appearing in the prime factorization of any natural number n "on average". More precisely, if we define H (1) = 1 and H ( n ) = the largest exponent appearing in the unique prime factorization of a natural number n > 1, then Niven's ... | https://en.wikipedia.org/wiki/Niven's_constant |
In mathematics , Niven's theorem , named after Ivan Niven , states that the only rational values of θ in the interval 0° ≤ θ ≤ 90° for which the sine of θ degrees is also a rational number are: [ 1 ]
In radians , one would require that 0° ≤ x ≤ π /2 , that x / π be rational, and that sin( x ) be rational. The conclus... | https://en.wikipedia.org/wiki/Niven's_theorem |
In nonmonotonic reasoning , the Nixon diamond is a scenario in which default assumptions lead to mutually inconsistent conclusions. The scenario is:
Since Nixon is a Quaker, one could assume that he is a pacifist; since he is Republican, however, one could also assume he is not a pacifist. The problem is how a formal ... | https://en.wikipedia.org/wiki/Nixon_diamond |
Niyazi Serdar Sarıçiftçi (born 1961 in Konya , Turkey ) is a Turkish-Austrian physicist. He is professor for physical chemistry at the Johannes Kepler University (JKU) Linz . There, he leads the Institut for Physical Chemistry as well as the Institut for Organic Solar Cells (LIOS).
Niyazi Serdar Sarıçiftçi graduated f... | https://en.wikipedia.org/wiki/Niyazi_Serdar_Sarıçiftçi |
In paleoecology and ecological forecasting , a no-analog [ 1 ] community or climate is one that is compositionally different from a (typically modern) baseline for measurement. [ 2 ] [ 3 ] Alternative naming conventions to describe no-analog communities and climates may include novel, emerging, mosaic, disharmonious an... | https://en.wikipedia.org/wiki/No-analog_(ecology) |
The no-observed-adverse-effect level ( NOAEL ) denotes the level of exposure of an organism , found by experiment or observation , at which there is no biologically or statistically significant increase in the frequency or severity of any adverse effects of the tested protocol. In drug development, the NOAEL of a new d... | https://en.wikipedia.org/wiki/No-observed-adverse-effect_level |
In fluid dynamics , the no-slip condition is a boundary condition which enforces that at a solid boundary, a viscous fluid attains zero bulk velocity . This boundary condition was first proposed by Osborne Reynolds , who observed this behaviour while performing his influential pipe flow experiments. [ 1 ] The form of t... | https://en.wikipedia.org/wiki/No-slip_condition |
In quantum information theory , the no-teleportation theorem states that an arbitrary quantum state cannot be converted into a sequence of classical bits (or even an infinite number of such bits); nor can such bits be used to reconstruct the original state, thus "teleporting" it by merely moving classical bits around. ... | https://en.wikipedia.org/wiki/No-teleportation_theorem |
In financial economics , the no-trade theorem states that if
then even though some traders may possess private information, none of them will be in a position to profit from it. The assumptions are deliberately unrealistic, but the theorem may nonetheless be pertinent to debates over inside information .
It was demo... | https://en.wikipedia.org/wiki/No-trade_theorem |
In mathematics , the no-wandering-domain theorem is a result on dynamical systems , proven by Dennis Sullivan in 1985.
The theorem states that a rational map f : Ĉ → Ĉ with deg( f ) ≥ 2 does not have a wandering domain , where Ĉ denotes the Riemann sphere . More precisely, for every component U in the Fatou set of f... | https://en.wikipedia.org/wiki/No-wandering-domain_theorem |
A no-win situation or lose–lose situation is an outcome of a negotiation , conflict or challenging circumstance in which all parties are worse off. It is an alternative to a win–win or outcome in which one party wins . Arbitration or mediation may be used to avoid no-win outcomes and find more satisfactory results. [ ... | https://en.wikipedia.org/wiki/No-win_situation |
The No.1 -class patrol boat ( 第一号型哨戒特務艇, , Dai Ichi Gō -gata Shōkai-Tokumutei ) was a class of auxiliary patrol boat (picket boat) of the Imperial Japanese Navy (IJN), serving during World War II . 280 vessels were planned under the Maru Sen Programme (Ship # 2121–2400), however, only 27 vessels were completed before t... | https://en.wikipedia.org/wiki/No.1-class_patrol_boat_(1945) |
No7 is a beauty brand of anti-ageing creams , skincare and cosmetic products developed by Boots in the United Kingdom . [ 1 ] The brand No7 was launched by Boots in 1935 [ 2 ] as a selection of eleven skincare products and was expanded in 1937 with some colour cosmetics. [ 3 ] [ 4 ] Since its introduction, the brand ha... | https://en.wikipedia.org/wiki/No._7_(brand) |
In mathematical folklore , the " no free lunch " ( NFL ) theorem (sometimes pluralized) of David Wolpert and William Macready , alludes to the saying " no such thing as a free lunch ", that is, there are no easy shortcuts to success. It appeared in the 1997 "No Free Lunch Theorems for Optimization". [ 1 ] Wolpert had p... | https://en.wikipedia.org/wiki/No_free_lunch_theorem |
The general prohibition sign , [ 1 ] also known informally as the no symbol , ' do not' sign , circle-backslash symbol , nay , interdictory circle , prohibited symbol , is a red circle with a 45-degree diagonal line inside the circle from upper-left to lower-right. It is typically overlaid on a pictogram to warn that a... | https://en.wikipedia.org/wiki/No_symbol |
No value added ( NVA ) is a management term loosely related to the lean manufacturing movement as codified in the 1980s by a landmark MIT study [ 1 ] of the automobile industry , which explained lean production for the first time.
No Value Added programs can be formal or whimsical. Generally, they involved seeking inp... | https://en.wikipedia.org/wiki/No_value_added |
This page provides supplementary data about the noble gases , which were excluded from the main article to conserve space and preserve focus. Oganesson mostly not included due to the amount of research known about it.
Radon is available only in very small quantities, and due to its short half-life, is generally produc... | https://en.wikipedia.org/wiki/Noble_gas_(data_page) |
A noble metal is ordinarily regarded as a metallic element that is generally resistant to corrosion and is usually found in nature in its raw form . Gold , platinum , and the other platinum group metals ( ruthenium , rhodium , palladium , osmium , iridium ) are most often so classified. Silver , copper , and mercury ar... | https://en.wikipedia.org/wiki/Noble_metal |
Noboru Tokita (February 20, 1923 - October 31, 2014) was a Uniroyal and later Cabot scientist known for his work on the processing of elastomers. [ 1 ]
Tokita was born in Sapporo, Japan in 1923. He met his wife Noriko while on an exchange program at Duke University. They married and decided to stay in the United State... | https://en.wikipedia.org/wiki/Noboru_Tokita |
A nocebo effect is said to occur when a patient's expectations for a treatment cause the treatment to have a worse effect than it otherwise would have. [ 1 ] [ 2 ] For example, when a patient anticipates a side effect of a medication, they can experience that effect even if the "medication" is actually an inert substan... | https://en.wikipedia.org/wiki/Nocebo |
Nocodazole is an antineoplastic agent which exerts its effect in cells by interfering with the polymerization of microtubules . [ 1 ] Microtubules are one type of fibre which constitutes the cytoskeleton , and the dynamic microtubule network has several important roles in the cell, including vesicular transport, formin... | https://en.wikipedia.org/wiki/Nocodazole |
A nocturnal is an instrument used to determine the local time based on the position of a star in the night sky relative to the pole star . As a result of the Earth's rotation , any fixed star makes a full revolution around the pole star in 23 hours and 56 minutes and therefore can be used as an hour hand . The 4-minute... | https://en.wikipedia.org/wiki/Nocturnal_(instrument) |
The nocturnal bottleneck hypothesis is an evolutionary biology hypothesis to explain the origin of several mammalian traits. In 1942, Gordon Lynn Walls described this concept which states that placental mammals were mainly or even exclusively nocturnal through most of their evolutionary history, from their origin 225 m... | https://en.wikipedia.org/wiki/Nocturnal_bottleneck |
Nocturnality is a behavior in some non-human animals characterized by being active during the night and sleeping during the day . The common adjective is " nocturnal ", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed senses of hearing , smell , and specially adapted eyesight . ... | https://en.wikipedia.org/wiki/Nocturnality |
Nod factors ( nodulation factors or NF ), are signaling molecules produced by soil bacteria known as rhizobia in response to flavonoid exudation from plants under nitrogen limited conditions. Nod factors initiate the establishment of a symbiotic relationship between legumes and rhizobia by inducing nodulation. Nod fact... | https://en.wikipedia.org/wiki/Nod_factor |
In power engineering , nodal admittance matrix (or just admittance matrix ) is an N x N matrix describing a linear power system with N buses . It represents the nodal admittance of the buses in a power system. In realistic systems which contain thousands of buses, the admittance matrix is quite sparse. Each bus in a ... | https://en.wikipedia.org/wiki/Nodal_admittance_matrix |
In electric circuit analysis, nodal analysis (also referred to as node-voltage analysis or the branch current method ) is a method of determining the voltage between nodes (points where elements or branches connect) in an electrical circuit in terms of the branch currents.
Nodal analysis is essentially a systematic ap... | https://en.wikipedia.org/wiki/Nodal_analysis |
Nodamuvirales is an order of positive-strand RNA viruses which infect eukaryotes . [ 1 ] The name of the group is a contraction of " Nodamu ra virus " and - virales which is the suffix for a virus order . [ 2 ]
The following families are recognized:
This virus -related article is a stub . You can help Wikipedia by e... | https://en.wikipedia.org/wiki/Nodamuvirales |
In physics and geometry , the nodary is the curve that is traced by the focus of a hyperbola as it rolls without slipping along the axis, a roulette curve . [ 1 ]
The differential equation of the curve is: y 2 + 2 a y 1 + y ′ 2 = b 2 {\displaystyle y^{2}+{\frac {2ay}{\sqrt {1+y'^{2}}}}=b^{2}} .
Its parametric equatio... | https://en.wikipedia.org/wiki/Nodary |
A node is a point along a standing wave where the wave has minimum amplitude . For instance, in a vibrating guitar string, the ends of the string are nodes. By changing the position of the end node through frets , the guitarist changes the effective length of the vibrating string and thereby the note played. The oppo... | https://en.wikipedia.org/wiki/Node_(physics) |
In graph theory and network analysis , node influence metrics are measures that rank or quantify the influence of every node (also called vertex) within a graph. They are related to centrality indices . Applications include measuring the influence of each person in a social network , understanding the role of infrastru... | https://en.wikipedia.org/wiki/Node_influence_metric |
Nodes of Ranvier ( / ˈ r ɑː n v i eɪ / RAHN -vee-ay ), [ 1 ] [ 2 ] also known as myelin-sheath gaps , occur along a myelinated axon where the axolemma is exposed to the extracellular space . Nodes of Ranvier are uninsulated axonal domains that are high in sodium and potassium ion channels complexed with cell adhesion m... | https://en.wikipedia.org/wiki/Node_of_Ranvier |
In differential geometry , a nodoid is a surface of revolution with constant nonzero mean curvature obtained by rolling a hyperbola along a fixed line, tracing the focus , and revolving the resulting nodary curve around the line. [ 1 ]
This geometry-related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Nodoid |
Noel Fitzpatrick is an Irish veterinary surgeon , based in Eashing , Surrey , who came to prominence through the television programme The Supervet .
Originally from Ballyfin , in County Laois , Ireland, he moved to Guildford , Surrey , in 1993, [ 2 ] where he is director and managing clinician at Fitzpatrick Referrals... | https://en.wikipedia.org/wiki/Noel_Fitzpatrick |
In mathematics and theoretical physics , Noether's second theorem relates symmetries of an action functional with a system of differential equations . [ 1 ] The theorem is named after its discoverer, Emmy Noether .
The action S of a physical system is an integral of a so-called Lagrangian function L , from which the s... | https://en.wikipedia.org/wiki/Noether's_second_theorem |
Noether's theorem states that every continuous symmetry of the action of a physical system with conservative forces has a corresponding conservation law . This is the first of two theorems (see Noether's second theorem ) published by the mathematician Emmy Noether in 1918. [ 1 ] The action of a physical system is the i... | https://en.wikipedia.org/wiki/Noether's_theorem |
In mathematics, Noether identities characterize the degeneracy of a Lagrangian system. Given a Lagrangian system and its Lagrangian L , Noether identities can be defined as a differential operator whose kernel contains a range of the Euler–Lagrange operator of L . Any Euler–Lagrange operator obeys Noether identities wh... | https://en.wikipedia.org/wiki/Noether_identities |
In mathematics , the Noether inequality , named after Max Noether , is a property of compact minimal complex surfaces that restricts the topological type of the underlying topological 4-manifold . It holds more generally for minimal projective surfaces of general type over an algebraically closed field.
Let X be a smo... | https://en.wikipedia.org/wiki/Noether_inequality |
In mathematics, the adjective Noetherian is used to describe objects that satisfy an ascending or descending chain condition on certain kinds of subobjects, meaning that certain ascending or descending sequences of subobjects must have finite length. Noetherian objects are named after Emmy Noether , who was the first t... | https://en.wikipedia.org/wiki/Noetherian |
Nofence is a Norwegian company that makes GPS collars for farm animals (cattle, sheep, and goats) that discourage them from crossing virtual fence boundaries. [ 1 ] [ 2 ]
Oscar Hovde Berntsen has been working on the idea of virtual fencing, as an alternative to fixed electric fencing , since the 1990s. [ 3 ] Nofence w... | https://en.wikipedia.org/wiki/Nofence |
Noise, vibration, and harshness ( NVH ), also known as noise and vibration ( N&V ), is the study and modification of the noise and vibration characteristics of vehicles , particularly cars and trucks . While noise and vibration can be readily measured, harshness is a subjective quality, and is measured either via jury ... | https://en.wikipedia.org/wiki/Noise,_vibration,_and_harshness |
Noise-cancelling headphones are headphones that suppress unwanted ambient sounds using active noise control ( ANC ).
Active noise cancellation makes it possible to listen to audio content without raising the volume excessively. In an aviation environment, noise-cancelling headphones increase the signal-to-noise ratio ... | https://en.wikipedia.org/wiki/Noise-cancelling_headphones |
Noise-domain reflectometry is a type of reflectometry where the reflectometer exploits existing data signals on wiring and does not have to generate any signals itself. [ 1 ] Noise-domain reflectometry, like time-domain and spread-spectrum time domain reflectometers , is most often used in identifying the location of w... | https://en.wikipedia.org/wiki/Noise-domain_reflectometry |
In optics the noise-equivalent flux density ( NEFD ) or noise-equivalent irradiance ( NEI ) of a system is the level of flux density required to be equivalent to the noise present in the system. [ 1 ] It is a measure used by astronomers in determining the accuracy of observations. [ 2 ]
The NEFD can be related to a li... | https://en.wikipedia.org/wiki/Noise-equivalent_flux_density |
Noise-immune cavity-enhanced optical-heterodyne molecular spectroscopy ( NICE-OHMS ) is an ultra-sensitive laser-based absorption technique that utilizes laser light to assess the concentration or the amount of a species in gas phase by absorption spectrometry (AS).
The NICE-OHMS technique combines cavity enhanced abs... | https://en.wikipedia.org/wiki/Noise-immune_cavity-enhanced_optical_heterodyne_molecular_spectroscopy |
Noise-induced order is a mathematical phenomenon appearing in the Matsumoto-Tsuda [ 1 ] model of the Belosov-Zhabotinski reaction .
In this model, adding noise to the system causes a transition from a "chaotic" behaviour to a more "ordered" behaviour; this article was a seminal paper in the area and generated a big nu... | https://en.wikipedia.org/wiki/Noise-induced_order |
A noise barrier (also called a soundwall , noise wall , sound berm , sound barrier , or acoustical barrier ) is an exterior structure designed to protect inhabitants of sensitive land use areas from noise pollution . Noise barriers are the most effective method of mitigating roadway , railway, and industrial noise sour... | https://en.wikipedia.org/wiki/Noise_barrier |
In the design of radio receivers , a noise blanker is a circuit intended to reduce the effect of certain kinds of radio noise on a received signal. [ 1 ] It is often used on broadcast shortwave receivers or communications receivers and some types of two-way radio transceivers . [ 2 ] The noise blanker is only effective... | https://en.wikipedia.org/wiki/Noise_blanker |
Noise control or noise mitigation is a set of strategies to reduce noise pollution or to reduce the impact of that noise, whether outdoors or indoors.
The main areas of noise mitigation or abatement are: transportation noise control, architectural design, urban planning through zoning codes , [ 1 ] and occupational no... | https://en.wikipedia.org/wiki/Noise_control |
In electrical engineering , Noise margin is the maximum voltage amplitude of extraneous signal that can be algebraically added to the noise-free worst-case input level without causing the output voltage to deviate from the allowable logic voltage level. [ 1 ] It is commonly used in at least two contexts as follows:
In... | https://en.wikipedia.org/wiki/Noise_margin |
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