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The O/OREOS (Organism/Organic Exposure to Orbital Stresses) is a NASA automated CubeSat nanosatellite laboratory approximately the size of a loaf of bread that contains two separate astrobiology experiments on board. [ 1 ] Developed by the Small Spacecraft Division at NASA Ames Research Center , the spacecraft was succ...
https://en.wikipedia.org/wiki/O/OREOS
Acetylacetone is an organic compound with the chemical formula CH 3 −C(=O)−CH 2 −C(=O)−CH 3 . It is classified as a 1,3- diketone . It exists in equilibrium with a tautomer CH 3 −C(=O)−CH=C(−OH)−CH 3 . The mixture is a colorless liquid. These tautomers interconvert so rapidly under most conditions that they are treated...
https://en.wikipedia.org/wiki/O2C5H7
Oxygen fluorides are compounds of elements oxygen and fluorine with the general formula O n F 2 , where n = 1 to 6. Many different oxygen fluorides are known: Oxygen fluorides are strong oxidizing agents with high energy and can release their energy either instantaneously or at a controlled rate. Thus, these compounds...
https://en.wikipedia.org/wiki/O2F
Dioxygen difluoride is a compound of fluorine and oxygen with the molecular formula O 2 F 2 . It can exist as an orange-red colored solid which melts into a red liquid at −163 °C (110 K). It is an extremely strong oxidant and decomposes into oxygen and fluorine even at −160 °C (113 K) at a rate of 4% per day — its life...
https://en.wikipedia.org/wiki/O2F2
Dioxidanylium, which is protonated molecular oxygen, or just protonated oxygen, is an ion with formula HO + 2 . It is formed when hydrogen containing substances combust , and exists in the ionosphere , and in plasmas that contain oxygen and hydrogen . [ 2 ] Oxidation by O 2 in superacids could be by way of the producti...
https://en.wikipedia.org/wiki/O2H+
Dinitrogen tetroxide , commonly referred to as nitrogen tetroxide ( NTO ), and occasionally (usually among ex-USSR/Russian rocket engineers) as amyl , is the chemical compound N 2 O 4 . It is a useful reagent in chemical synthesis. It forms an equilibrium mixture with nitrogen dioxide . Its molar mass is 92.011 g/mol. ...
https://en.wikipedia.org/wiki/O2N-NO2
Lead(IV) oxide , commonly known as lead dioxide , is an inorganic compound with the chemical formula PbO 2 . It is an oxide where lead is in an oxidation state of +4. [ 1 ] It is a dark-brown solid which is insoluble in water. [ 2 ] It exists in two crystalline forms. It has several important applications in electroche...
https://en.wikipedia.org/wiki/O2Pb
Dioxygenyl hexafluoroplatinate is a compound with formula O 2 PtF 6 . It is a hexafluoroplatinate of the unusual dioxygenyl cation, O 2 + , and is the first known compound containing this cation. [ 1 ] It can be produced by the reaction of dioxygen with platinum hexafluoride . The fact that PtF 6 is strong enough to ox...
https://en.wikipedia.org/wiki/O2PtF6
Plutonium(IV) oxide , or plutonia , is a chemical compound with the formula Pu O 2 . This high melting-point solid is a principal compound of plutonium . It can vary in color from yellow to olive green, depending on the particle size, temperature and method of production. [ 2 ] PuO 2 crystallizes in the fluorite motif...
https://en.wikipedia.org/wiki/O2Pu
Selenium dioxide is the chemical compound with the formula SeO 2 . This colorless solid is one of the most frequently encountered compounds of selenium . It is used in making specialized glasses as well as a reagent in organic chemistry. [ 4 ] Solid SeO 2 is a one-dimensional polymer , the chain consisting of alterna...
https://en.wikipedia.org/wiki/O2Se
Silicon dioxide , also known as silica , is an oxide of silicon with the chemical formula SiO 2 , commonly found in nature as quartz . [ 5 ] [ 6 ] In many parts of the world, silica is the major constituent of sand . Silica is one of the most complex and abundant families of materials , existing as a compound of severa...
https://en.wikipedia.org/wiki/O2Si
Tellurium dioxide (TeO 2 ) is a solid oxide of tellurium . It is encountered in two different forms, the yellow orthorhombic mineral tellurite , β-TeO 2 , and the synthetic, colourless tetragonal (paratellurite), α-TeO 2 . [ 2 ] Most of the information regarding reaction chemistry has been obtained in studies involving...
https://en.wikipedia.org/wiki/O2Te
Thorium dioxide (ThO 2 ), also called thorium(IV) oxide , is a crystalline solid, often white or yellow in colour. Also known as thoria , it is mainly a by-product of lanthanide and uranium production. [ 4 ] Thorianite is the name of the mineralogical form of thorium dioxide. It is moderately rare and crystallizes in ...
https://en.wikipedia.org/wiki/O2Th
Oxygen fluorides are compounds of elements oxygen and fluorine with the general formula O n F 2 , where n = 1 to 6. Many different oxygen fluorides are known: Oxygen fluorides are strong oxidizing agents with high energy and can release their energy either instantaneously or at a controlled rate. Thus, these compounds...
https://en.wikipedia.org/wiki/O3F2
Antimony(III) oxide is the inorganic compound with the formula Sb 2 O 3 . It is the most important commercial compound of antimony . It is found in nature as the minerals valentinite and senarmontite. [ 3 ] Like most polymeric oxides , Sb 2 O 3 dissolves in aqueous solutions with hydrolysis . A mixed arsenic-antimony...
https://en.wikipedia.org/wiki/O3Sb2
Scandium(III) oxide or scandia is a inorganic compound with formula Sc 2 O 3 . It is one of several oxides of rare earth elements with a high melting point . It is used in the preparation of other scandium compounds as well as in high-temperature systems (for its resistance to heat and thermal shock ), electronic cera...
https://en.wikipedia.org/wiki/O3Sc2
Selenium trioxide is the inorganic compound with the formula Se O 3 . It is white, hygroscopic solid. It is also an oxidizing agent and a Lewis acid . It is of academic interest as a precursor to Se(VI) compounds. [ 4 ] Selenium trioxide is difficult to prepare because it is unstable with respect to the dioxide : I...
https://en.wikipedia.org/wiki/O3Se
Tausonite Strontium titanate is an oxide of strontium and titanium with the chemical formula Sr Ti O 3 . At room temperature, it is a centrosymmetric paraelectric material with a perovskite structure. At low temperatures it approaches a ferroelectric phase transition with a very large dielectric constant ~10 4 but rem...
https://en.wikipedia.org/wiki/O3SrTi
Thallium(III) oxide , also known as thallic oxide , is a chemical compound of thallium and oxygen . It occurs in nature as the rare mineral avicennite . [ 4 ] Its structure is related to that of Mn 2 O 3 which has a bixbyite like structure. Tl 2 O 3 is metallic with high conductivity and is a degenerate n-type semicond...
https://en.wikipedia.org/wiki/O3Tl2
Vanadium(III) oxide is the inorganic compound with the formula V 2 O 3 . It is a black solid prepared by reduction of V 2 O 5 with hydrogen or carbon monoxide . [ 3 ] [ 4 ] It is a basic oxide dissolving in acids to give solutions of vanadium (III) complexes. [ 4 ] V 2 O 3 has the corundum structure. [ 4 ] It is antif...
https://en.wikipedia.org/wiki/O3V2
Yttrium oxide , also known as yttria , is Y 2 O 3 . It is an air-stable, white solid substance . The thermal conductivity of yttrium oxide is 27 W/(m·K). [ 5 ] Yttrium oxide is widely used to make Eu:YVO 4 and Eu:Y 2 O 3 phosphors that give the red color in color TV picture tubes. Y 2 O 3 is a prospective solid-stat...
https://en.wikipedia.org/wiki/O3Y2
Ytterbium(III) oxide is the chemical compound with the formula Yb 2 O 3 . It is one of the more commonly encountered compounds of ytterbium . It occurs naturally in trace amounts in the mineral gadolinite . It was first isolated from this in 1878 by Jean Charles Galissard de Marignac . [ 3 ] Ytterbium(III) oxide can b...
https://en.wikipedia.org/wiki/O3Yb2
Tetraoxygen difluoride is an inorganic chemical compound of oxygen, belonging to the family of oxygen fluorides . It consists of two O 2 F units bound together with a weak O-O bond, and is the dimer of the O 2 F radical. [ 1 ] Tetraoxygen difluoride can be prepared in two steps. In the first step, a photochemically ge...
https://en.wikipedia.org/wiki/O4F2
soluble in ammonium acetate (≥ 6 mol/L) soluble in ammonium tartrate in presence of ammonium chloride and ammonia Lead(II) sulfate (PbSO 4 ) is a white solid, which appears white in microcrystalline form. It is also known as fast white , milk white , sulfuric acid lead salt or anglesite . It is often seen in the pla...
https://en.wikipedia.org/wiki/O4PbS
Ruthenium tetroxide is the inorganic compound with the formula RuO 4 . It is a yellow volatile solid that melts near room temperature. [ 3 ] It has the odor of ozone. [ 4 ] Samples are typically black due to impurities. The analogous OsO 4 is more widely used and better known. It is also the anhydride of hyperruthenic ...
https://en.wikipedia.org/wiki/O4Ru
Zinc sulfate is an inorganic compound with the formula ZnSO 4 . It forms hydrates ZnSO 4 · n H 2 O, where n can range from 0 to 7. All are colorless solids. The most common form includes water of crystallization as the heptahydrate, [ 4 ] with the formula Zn SO 4 ·7H 2 O . As early as the 16th century it was prepared o...
https://en.wikipedia.org/wiki/O4SZn
Xenon tetroxide is a chemical compound of xenon and oxygen with molecular formula XeO 4 , remarkable for being a relatively stable compound of a noble gas . It is a yellow crystalline solid that is stable below −35.9 ° C ; above that temperature it is very prone to exploding and decomposing into elemental xenon and oxy...
https://en.wikipedia.org/wiki/O4Xe
Phosphorus pentoxide is a chemical compound with molecular formula P 4 O 10 (with its common name derived from its empirical formula , P 2 O 5 ). This white crystalline solid is the anhydride of phosphoric acid . It is a powerful desiccant and dehydrating agent . Phosphorus pentoxide crystallizes in at least four form...
https://en.wikipedia.org/wiki/O5P2
Vanadyl(IV) sulfate describes a collection of inorganic compounds of vanadium with the formula, VOSO 4 (H 2 O) x where 0 ≤ x ≤ 6. The pentahydrate is common. This hygroscopic blue solid is one of the most common sources of vanadium in the laboratory, reflecting its high stability. It features the vanadyl ion, VO 2+ , w...
https://en.wikipedia.org/wiki/O5SV
Tantalum pentoxide , also known as tantalum (V) oxide, is the inorganic compound with the formula Ta 2 O 5 . It is a white solid that is insoluble in all solvents but is attacked by strong bases and hydrofluoric acid . Ta 2 O 5 is an inert material with a high refractive index and low absorption (i.e. colourless), whic...
https://en.wikipedia.org/wiki/O5Ta2
C 0.1 mg V 2 O 5 /m 3 (fume) [ 6 ] Vanadium(V) oxide ( vanadia ) is the inorganic compound with the formula V 2 O 5 . Commonly known as vanadium pentoxide , it is a dark yellow solid, although when freshly precipitated from aqueous solution, its colour is deep orange. Because of its high oxidation state , it is both...
https://en.wikipedia.org/wiki/O5V2
Dichlorine heptoxide is the chemical compound with the formula Cl 2 O 7 . This chlorine oxide is the anhydride of perchloric acid . It is produced by the careful distillation of perchloric acid in the presence of the dehydrating agent phosphorus pentoxide : [ 1 ] Cl 2 O 7 can be distilled off from the mixture. It may...
https://en.wikipedia.org/wiki/O7Cl2
Triuranium octoxide (U 3 O 8 ) [ 4 ] is a compound of uranium . It is present as an olive green to black, odorless solid. It is one of the more popular forms of yellowcake and is shipped between mills and refineries in this form. U 3 O 8 has potential long-term stability in a geologic environment . [ 5 ] In the presen...
https://en.wikipedia.org/wiki/O8U3
Formic acid (from Latin formica ' ant ' ), systematically named methanoic acid , is the simplest carboxylic acid . It has the chemical formula HCOOH and structure H−C(=O)−O−H . This acid is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Esters , salts , and the anion de...
https://en.wikipedia.org/wiki/O=CH-O-H
Formic acid (from Latin formica ' ant ' ), systematically named methanoic acid , is the simplest carboxylic acid . It has the chemical formula HCOOH and structure H−C(=O)−O−H . This acid is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Esters , salts , and the anion de...
https://en.wikipedia.org/wiki/O=CH-OH
Formaldehyde ( / f ɔːr ˈ m æ l d ɪ h aɪ d / ⓘ for- MAL -di-hide , US also / f ə r -/ ⓘ fər- ) ( systematic name methanal ) is an organic compound with the chemical formula CH 2 O and structure H−CHO , more precisely H 2 C=O . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde...
https://en.wikipedia.org/wiki/O=CH2
The nitrite ion has the chemical formula NO − 2 . Nitrite (mostly sodium nitrite ) is widely used throughout chemical and pharmaceutical industries. [ 1 ] The nitrite anion is a pervasive intermediate in the nitrogen cycle in nature. The name nitrite also refers to organic compounds having the –ONO group, which are est...
https://en.wikipedia.org/wiki/O=N-O
The nitrite ion has the chemical formula NO − 2 . Nitrite (mostly sodium nitrite ) is widely used throughout chemical and pharmaceutical industries. [ 1 ] The nitrite anion is a pervasive intermediate in the nitrogen cycle in nature. The name nitrite also refers to organic compounds having the –ONO group, which are est...
https://en.wikipedia.org/wiki/O=N−O−
Ozone ( / ˈ oʊ z oʊ n / ) (or trioxygen ) is an inorganic molecule with the chemical formula O 3 . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope O 2 , breaking down in the lower atmosphere to O 2 ( dioxygen ). Ozone is formed ...
https://en.wikipedia.org/wiki/O=O-O
The Open Biological and Biomedical Ontologies ( OBO ) Foundry is a group of people who build and maintain ontologies related to the life sciences . [ 1 ] The OBO Foundry establishes a set of principles for ontology development for creating a suite of interoperable reference ontologies in the biomedical domain. Currentl...
https://en.wikipedia.org/wiki/OBO_Foundry
Carbonic acid is a chemical compound with the chemical formula H 2 C O 3 . The molecule rapidly converts to water and carbon dioxide in the presence of water. However, in the absence of water, it is quite stable at room temperature . [ 5 ] [ 6 ] The interconversion of carbon dioxide and carbonic acid is related to the ...
https://en.wikipedia.org/wiki/OC(OH)2
Formaldehyde ( / f ɔːr ˈ m æ l d ɪ h aɪ d / ⓘ for- MAL -di-hide , US also / f ə r -/ ⓘ fər- ) ( systematic name methanal ) is an organic compound with the chemical formula CH 2 O and structure H−CHO , more precisely H 2 C=O . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde...
https://en.wikipedia.org/wiki/OCH2
4CMN , 2KIE , 2QV2 , 3QBT , 3QIS 4952 320634 ENSG00000122126 ENSMUSG00000001173 Q01968 Q6NVF0 NM_000276 NM_001587 NM_001318784 NM_177215 NP_000267 NP_001305713 NP_001578 NP_796189 Inositol polyphosphate 5-phosphatase OCRL-1 , also known as Lowe oculocerebrorenal syndrome protein , is an enzyme encoded by the...
https://en.wikipedia.org/wiki/OCRL
Carbonyl selenide is a chemical compound with the chemical formula O = C = Se . It is a linear molecule that is primarily of interest for research purposes. Carbonyl selenide is a colorless gas with an unpleasant odor. [ 1 ] Although the compound is quite stable, its solutions gradually revert to elemental selenium an...
https://en.wikipedia.org/wiki/OCSe
In wireless networking, On-Demand Multicast Routing Protocol is a protocol for routing multicast and unicast traffic throughout Ad hoc wireless mesh networks . ODMRP creates routes on demand, rather than proactively creating routes as OLSR does. This suffers from a route acquisition delay, although it helps reduce net...
https://en.wikipedia.org/wiki/ODMRP
OECD Guidelines for the Testing of Chemicals ( OECD TG ) are a set of internationally accepted specifications for the testing of chemicals decided on by the Organisation for Economic Co-operation and Development (OECD). They were first published in 1981. They are split into five sections: Guidelines are numbered with...
https://en.wikipedia.org/wiki/OECD_Guidelines_for_the_Testing_of_Chemicals
OELib was an open source Cheminformatics library written by Matt Stahl and based on the ideas of OBabel. [ 1 ] Its actual GPLed C++ and Java based successors are OpenBabel and JOELib , [ 2 ] with Its commercial successor being called OEChem . [ citation needed ] This software-engineering -related article is a stub . Y...
https://en.wikipedia.org/wiki/OELib
Oxygen difluoride is a chemical compound with the formula OF 2 . As predicted by VSEPR theory , the molecule adopts a bent molecular geometry . [ citation needed ] It is a strong oxidizer and has attracted attention in rocketry for this reason. [ 5 ] With a boiling point of −144.75 °C, OF 2 is the most volatile (isolab...
https://en.wikipedia.org/wiki/OF2
Hydroxide is a diatomic anion with chemical formula OH − . It consists of an oxygen and hydrogen atom held together by a single covalent bond , and carries a negative electric charge . It is an important but usually minor constituent of water . It functions as a base , a ligand , a nucleophile , and a catalyst . The hy...
https://en.wikipedia.org/wiki/OH-
Formic acid (from Latin formica ' ant ' ), systematically named methanoic acid , is the simplest carboxylic acid . It has the chemical formula HCOOH and structure H−C(=O)−O−H . This acid is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Esters , salts , and the anion de...
https://en.wikipedia.org/wiki/OHCHO
Carbonic acid is a chemical compound with the chemical formula H 2 C O 3 . The molecule rapidly converts to water and carbon dioxide in the presence of water. However, in the absence of water, it is quite stable at room temperature . [ 5 ] [ 6 ] The interconversion of carbon dioxide and carbonic acid is related to the ...
https://en.wikipedia.org/wiki/OHCOOH
OJSC Dolomite ( Russian : ОАО Доломит ) forms part of the Russia metallurgical complex, being the only producer of metallurgical dolomite in the Central Black Earth economic region . The company mines 55% of the total amount of dolomite produced in Russia and 43% in CIS. It is part of the NLMK Group. [ 1 ] The company...
https://en.wikipedia.org/wiki/OJSC_Dolomite
OLAC , the Open Language Archives Community , is an initiative to create a unified means of searching online databases of language resources for linguistic research. The information about resources is stored in XML format for easy searching. OLAC was founded in 2000, and is hosted at the Linguistic Data Consortium webs...
https://en.wikipedia.org/wiki/OLAC
An organic light-emitting diode ( OLED ), also known as organic electroluminescent ( organic EL ) diode , [ 1 ] [ 2 ] is a type of light-emitting diode (LED) in which the emissive electroluminescent layer is an organic compound film that emits light in response to an electric current. This organic layer is situated bet...
https://en.wikipedia.org/wiki/OLED
OLGA is a modelling tool for transportation of oil , natural gas and water in the same pipeline , so-called multiphase transportation. The name is short for "oil and gas simulator". The main challenge with multiphase fluid flow is the formation of slugs (plugs of oil and water) in the pipelines, which causes large prob...
https://en.wikipedia.org/wiki/OLGA_(technology)
The OMA Instant Messaging and Presence Service ( IMPS ) is an Open Mobile Alliance enabler for Instant Messaging and Presence. The Wireless Village consortium developed the first cut of the specifications. After Wireless Village was merged with OMA, its specs became OMA IMPS 1.0 specifications. IMPS is widely deploye...
https://en.wikipedia.org/wiki/OMA_Instant_Messaging_and_Presence_Service
OMDoc (Open Mathematical Documents) is a semantic markup format for mathematical documents. While MathML only covers mathematical formulae and the related OpenMath standard only supports formulae and “content dictionaries” containing definitions of the symbols used in formulae, OMDoc covers the whole range of written m...
https://en.wikipedia.org/wiki/OMDoc
The OMEGA process ("Only MEG Advantage") [ 1 ] is a chemical process discovered by the Shell Global Solutions company that is used to produce ethylene glycol from ethylene . This process comprises two steps, the controlled oxidation of ethylene to ethylene oxide , and the net hydrolysis of ethylene oxide to monoethylen...
https://en.wikipedia.org/wiki/OMEGA_process
OMEMO is an extension to the Extensible Messaging and Presence Protocol ( XMPP ) for multi-client end-to-end encryption developed by Andreas Straub . According to Straub, OMEMO uses the Double Ratchet Algorithm "to provide multi-end to multi-end encryption, allowing messages to be synchronized securely across multiple ...
https://en.wikipedia.org/wiki/OMEMO
OMNIS (Office des Mines Nationales et des Industries Stratégiques, formerly known as Office Militaire National pour les Industries Stratégiques) is the Malagasy government organisation, operating under the auspices of the Ministry of Energy, responsible for: Hydrocarbons: – Putting in place and updating the legal fram...
https://en.wikipedia.org/wiki/OMNIS
OMNeT++ ( O bjective M odular Ne twork T estbed in C ++ ) [ 1 ] is a modular, component-based C++ simulation library and framework, primarily for building network simulators. [ 2 ] [ 3 ] [ 4 ] OMNeT++ can be used for free for non-commercial simulations like at academic institutions and for teaching. [ 5 ] OMNEST is an ...
https://en.wikipedia.org/wiki/OMNeT++
ONETEP (Order-N Electronic Total Energy Package) is a linear-scaling density functional theory software package able to run on parallel computers . [ 1 ] It uses a basis of non-orthogonal generalized Wannier functions (NGWFs) expressed in terms of periodic cardinal sine (psinc) functions, which are in turn equivalent t...
https://en.wikipedia.org/wiki/ONETEP
The ONIOM (short for ' O ur own N -layered I ntegrated molecular O rbital and M olecular mechanics' [ 1 ] ) method is a computational approach developed by Keiji Morokuma and co-workers. ONIOM is a hybrid method that enables different ab initio , semi-empirical , or molecular mechanics methods to be applied to differen...
https://en.wikipedia.org/wiki/ONIOM
Trioctylphosphine oxide ( TOPO ) is an organophosphorus compound with the formula OP(C 8 H 17 ) 3 . Frequently referred to as TOPO, this compound is used as an extraction or stabilizing agent. It is an air-stable white solid at room temperature. It is lipophilic, and like other phosphine oxides serves as a Lewis base ...
https://en.wikipedia.org/wiki/OP(C8H17)3
This group of standards, created by the OPC Foundation , provides COM specifications for communicating data from devices and applications that provide historical data, such as databases. The specifications provides for access to raw, interpolated and aggregate data (data with calculations). OPC Historical Data Access,...
https://en.wikipedia.org/wiki/OPC_Historical_Data_Access
OPC Unified Architecture ( OPC UA ) is a cross-platform, open-source, IEC62541 standard for data exchange from sensors to cloud applications developed by the OPC Foundation . Distinguishing characteristics are: [ 1 ] Although developed by the same organization, OPC UA differs significantly from its predecessor, Open P...
https://en.wikipedia.org/wiki/OPC_Unified_Architecture
Phosphoryl chloride (commonly called phosphorus oxychloride ) is a colourless liquid with the formula P O Cl 3 . It hydrolyses in moist air releasing phosphoric acid and fumes of hydrogen chloride . It is manufactured industrially on a large scale from phosphorus trichloride and oxygen or phosphorus pentoxide . [ 4 ] I...
https://en.wikipedia.org/wiki/OPCl3
The OPLS (Optimized Potentials for Liquid Simulations) force field was developed by Prof. William L. Jorgensen at Purdue University and later at Yale University , and is being further developed commercially by Schrödinger, Inc . The functional form of the OPLS force field is very similar to that of AMBER : E ( r N ) ...
https://en.wikipedia.org/wiki/OPLS
ORCA was a mobile-optimized web application used as a component of the " get out the vote " (GOTV) efforts for Mitt Romney's 2012 presidential campaign . It was intended to enable volunteers in polling stations around the country to report which voters had turned out, so that "missing" Republican voters and underperfor...
https://en.wikipedia.org/wiki/ORCA_(computer_system)
ORCA [ 1 ] [ 2 ] [ 3 ] [ 4 ] is a general-purpose quantum chemistry package featuring a variety of methods including semi-empirical , density functional theory , many-body perturbation , coupled cluster , and multireference methods. ORCA provides an easy-to-learn input structure and thus high accessibility of quantum c...
https://en.wikipedia.org/wiki/ORCA_(quantum_chemistry_program)
Busek Company Incorporated is an American spacecraft propulsion company that builds thrusters , electronics , and various systems for spacecraft . Busek was founded in 1985 by Vlad Hruby in Natick, Massachusetts . [ 1 ] Busek started as a laboratory outside of Boston , Massachusetts . The first US Hall thruster flown...
https://en.wikipedia.org/wiki/ORDER_(spacecraft)
In molecular genetics , an ORFeome refers to the complete set of open reading frames (ORFs) in a genome . The term may also be used to describe a set of cloned ORFs. [ 1 ] ORFs correspond to the protein coding sequences (CDS) of genes . ORFs can be found in genome sequences by computer programs such as GENSCAN and then...
https://en.wikipedia.org/wiki/ORFeome
The ORTF stereo technique , also known as side-other-side , is a microphone technique used to record stereo sound . It was devised around 1960 at the now-defunct Office de Radiodiffusion Télévision Française (ORTF). This technique combines both the volume difference and the timing difference as sound arrives on- and o...
https://en.wikipedia.org/wiki/ORTF_stereo_technique
ORiN (Open Robot/Resource interface for the Network) is a standard network interface for FA ( factory automation ) systems. The Japan Robot Association proposed ORiN in 2002, and the ORiN Forum develops and maintains the ORiN standard. The installation of PC ( Personal Computer ) applications in the factory has increa...
https://en.wikipedia.org/wiki/ORiN
OS/4 is a discontinued operating system , introduced in 1972, from UNIVAC for their 9400, 9480, and 9700 computer systems. It is an enhanced version of UNIVAC's 9400 Disc Operating System. OS/4 is a disc-resident system requiring 64 KB of main memory , two disc drives , a punched-card reader and a printer . The residen...
https://en.wikipedia.org/wiki/OS/4
OS/7 is a discontinued operating system from Sperry Univac for its 90/60 and 90/70 computer systems. The system was first announced in November 1971 for Univac's 9700 system and was originally scheduled for delivery in March 1973. [ 1 ] [ 2 ] However, the delivery slipped by nearly a year, which impacted the 9700 marke...
https://en.wikipedia.org/wiki/OS/7
OSS/J (a.k.a. OSS through Java ) is a TM Forum [ 1 ] technical program whose primary goal is to develop open interface standards ( APIs ) for the integration of Business Support Systems (BSS) & Operations Support System (OSS). OSS/J addresses the concerns of Frameworx implementation stakeholders by providing open stan...
https://en.wikipedia.org/wiki/OSS/J
OSS/J (a.k.a. OSS through Java ) is a TM Forum [ 1 ] technical program whose primary goal is to develop open interface standards ( APIs ) for the integration of Business Support Systems (BSS) & Operations Support System (OSS). OSS/J addresses the concerns of Frameworx implementation stakeholders by providing open stan...
https://en.wikipedia.org/wiki/OSS_through_Java
OSv (stylized OS v ) is a cloud computing focused [ 1 ] computer operating system released on September 16, 2013. It is a special-purpose operating system built to run as a guest on top of a virtual machine, thus it does not include drivers for bare-metal hardware. It is a unikernel , designed to run a single Linux ex...
https://en.wikipedia.org/wiki/OSv
OVN ( Open Virtual Network ) is a system to support virtual network abstraction. OVN complements the existing capabilities of Open vSwitch to add native support for virtual network abstractions, such as virtual L2 and L3 overlays and security groups. OVN is a network virtualization platform that separates the physica...
https://en.wikipedia.org/wiki/OVN
The OWSD-Elsevier Foundation Awards for Early-Career Women Scientists in the Developing World are awarded annually to early-career women scientists in selected developing countries in four regions: Latin America and the Caribbean , East and Southeast Asia and the Pacific , Central and South Asia, and Sub-Saharan Africa...
https://en.wikipedia.org/wiki/OWSD-Elsevier_Foundation_Award
O mark is the name of the circle symbol "◯". [ citation needed ] It is often used in East Asia to express affirmation . Its use is similar to that of the checkmark ("✓") in the Western world . Its opposite is the X mark ("✗" or "×"). The symbol's names and meanings vary across cultures. In Japanese it is called maruji...
https://en.wikipedia.org/wiki/O_mark
Oak Investment Partners is a private equity firm focusing on venture capital investments in companies developing communications systems, information technology , new Internet media, healthcare services and retail. The firm, founded in 1978, is based in Greenwich, Connecticut , with offices in Norwalk, Connecticut , Mi...
https://en.wikipedia.org/wiki/Oak_Investment_Partners
In hydrology , oasification is the antonym to desertification by soil erosion . This technique has limited application and is normally considered for much smaller areas than those threatened by desertification. [ citation needed ] Oasification is also a developing direction of environmental engineering . To help the ...
https://en.wikipedia.org/wiki/Oasification
Oasis is a piece of software developed by the United States Central Intelligence Agency (CIA) that converts audio signals such as cellphone calls and television and radio broadcasts into readable and searchable text. [ 1 ] It is designed to intelligently analyze an audio signal such as a cellphone call in order to iden...
https://en.wikipedia.org/wiki/Oasis_(software)
The oasis effect refers to the creation of a local microclimate that is cooler than the surrounding dry area due to evaporation or evapotranspiration of a water source or plant life and higher albedo of plant life than bare ground. [ 1 ] The oasis effect is so-named because it occurs in desert oases . [ 2 ] Urban plann...
https://en.wikipedia.org/wiki/Oasis_effect
The traditional Korean color spectrum , also known as Obangsaek ( Korean : 오방색 ; lit. five direction colors), is the color scheme of the five Korean traditional colors of white , black , blue , red and yellow . [ 1 ] [ 2 ] In Korean traditional arts and traditional textile patterns, the colors of Obangsaek represent fi...
https://en.wikipedia.org/wiki/Obangsaek
Obash is a bash script obfuscator written in the C programming language . obash encodes and encrypts bash shell scripts into executable binaries much like shc , the project that inspired it, but uses AES-256 encryption and the key and initialization vector are retrieved from the hardware instead of being hard coded int...
https://en.wikipedia.org/wiki/Obash
Obcells are hypothetical proto-organisms or the earliest form of life. The term was first proposed by Thomas Cavalier-Smith in 2001. According to Cavalier-Smith's theory for the origin of the first cell, two cup-shaped obcells or hemicells fused to make a protocell with double-lipid layer envelope, internal genome and ...
https://en.wikipedia.org/wiki/Obcell
In astronautics , a powered flyby , or Oberth maneuver , is a maneuver in which a spacecraft falls into a gravitational well and then uses its engines to further accelerate as it is falling, thereby achieving additional speed. [ 1 ] The resulting maneuver is a more efficient way to gain kinetic energy than applying the...
https://en.wikipedia.org/wiki/Oberth_effect
In mathematics , the Oberwolfach problem is an open problem that may be formulated either as a problem of scheduling seating assignments for diners, or more abstractly as a problem in graph theory , on the edge cycle covers of complete graphs . It is named after the Oberwolfach Research Institute for Mathematics , wher...
https://en.wikipedia.org/wiki/Oberwolfach_problem
Obeya (from Japanese Ōbeya 大部屋 "large room") is a team spirit improvement tool at an administrative level, originating from a long history of learning & improving. It is considered a component of lean manufacturing . Obeya objectives are rapid decision-making, reduction in rework and reconsiderations, and reduction in ...
https://en.wikipedia.org/wiki/Obeya
The Obfuscated Perl Contest was a competition for programmers of Perl which was held annually between 1996 and 2000. Entrants to the competition aimed to write "devious, inhuman, disgusting, amusing, amazing, and bizarre Perl code". [ 1 ] It was run by The Perl Journal and took its name from the International Obfuscat...
https://en.wikipedia.org/wiki/Obfuscated_Perl_Contest
ObjectARX ( AutoCAD Runtime eXtension) is an API for customizing and extending AutoCAD . The ObjectARX SDK is published by Autodesk and freely available under license from Autodesk. [ 1 ] The ObjectARX SDK consists primarily of C++ headers and libraries that can be used to build Windows DLLs that can be loaded into the...
https://en.wikipedia.org/wiki/ObjectARX
Object process methodology ( OPM ) is a conceptual modeling language and methodology for capturing knowledge and designing systems , specified as ISO / PAS 19450. [ 1 ] Based on a minimal universal ontology of stateful objects and processes that transform them, OPM can be used to formally specify the function, structur...
https://en.wikipedia.org/wiki/Object_Process_Methodology
An object code optimizer , sometimes also known as a post pass optimizer or, for small sections of code, peephole optimizer , forms part of a software compiler . It takes the output from the source language compile step - the object code or binary file - and tries to replace identifiable sections of the code with repl...
https://en.wikipedia.org/wiki/Object_code_optimizer
In computer programming , an object orgy is a situation in which objects are insufficiently encapsulated via information hiding , allowing unrestricted access to their internals. This is a common failure (or anti-pattern ) in object-oriented design or object-oriented programming , and it can lead to increased maintenan...
https://en.wikipedia.org/wiki/Object_orgy
In optical engineering , an objective is an optical element that gathers light from an object being observed and focuses the light rays from it to produce a real image of the object. Objectives can be a single lens or mirror , or combinations of several optical elements. They are used in microscopes , binoculars , tele...
https://en.wikipedia.org/wiki/Objective_(optics)
As an adjective, obligate means "by necessity" (antonym facultative ) and is used mainly in biology in phrases such as:
https://en.wikipedia.org/wiki/Obligate
An obligate aerobe is an organism that requires oxygen to grow. [ 1 ] Through cellular respiration , these organisms use oxygen to metabolise substances, like sugars or fats, to obtain energy. [ 1 ] [ 2 ] In this type of respiration, oxygen serves as the terminal electron acceptor for the electron transport chain . [ 1...
https://en.wikipedia.org/wiki/Obligate_aerobe