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The Platinum-Cobalt Scale ( Pt/Co scale or Apha-Hazen Scale ) is a color scale that was introduced in 1892 by chemist Allen Hazen (1869–1930). The index was developed as a way to evaluate pollution levels in waste water. It has since expanded to a common method of comparison of the intensity of yellow-tinted samples. I... | https://en.wikipedia.org/wiki/Pt/Co_scale |
Platinum(IV) bromide is the inorganic compound with the formula PtBr 4 . It is a brown solid. It is a little-used compound mainly of interest for academic research. [ 2 ] It is a component of a reagent used in qualitative inorganic analysis . [ 3 ]
In terms of structure, the compound is an inorganic polymer consistin... | https://en.wikipedia.org/wiki/PtBr4 |
Platinum(II) chloride describes the inorganic compounds with the formula Pt Cl 2 . They are precursor used in the preparation of other platinum compounds. Platinum(II) chloride exists in two crystalline forms ( polymorphs ), but the main properties are somewhat similar: dark brown, insoluble in water, diamagnetic , and... | https://en.wikipedia.org/wiki/PtCl2 |
Bis(triphenylphosphine)platinum chloride is a metal phosphine complex with the formula PtCl 2 [P(C 6 H 5 ) 3 ] 2 . Cis- and trans isomers are known. The cis isomer is a white crystalline powder, while the trans isomer is yellow. [ 3 ] Both isomers are square planar about the central platinum atom. The cis isomer is use... | https://en.wikipedia.org/wiki/PtCl2(PPh3)2 |
Platinum(IV) chloride is the inorganic compound of platinum and chlorine with the empirical formula PtCl 4 . This brown solid features platinum in the +4 oxidation state.
Typical of Pt(IV), the metal centers adopt an octahedral coordination geometry , {PtCl 6 }. This geometry is achieved by forming a polymer wherein h... | https://en.wikipedia.org/wiki/PtCl4 |
Platinum tetrafluoride is the inorganic compound with the chemical formula PtF 4 . In the solid state, the compound features platinum(IV) in octahedral coordination geometry . [ 2 ]
The compound was first reported by Henri Moissan by the fluorination of platinum metal in the presence of hydrogen fluoride . [ 3 ] A mo... | https://en.wikipedia.org/wiki/PtF4 |
Platinum hexafluoride is the chemical compound with the formula Pt F 6 , and is one of seventeen known binary hexafluorides . It is a dark-red volatile solid that forms a red gas. The compound is a unique example of platinum in the +6 oxidation state. With only four d-electrons, it is paramagnetic with a triplet ground... | https://en.wikipedia.org/wiki/PtF6 |
Adams' catalyst , also known as platinum dioxide , is usually represented as platinum (IV) oxide hydrate , PtO 2 •H 2 O. It is a catalyst for hydrogenation and hydrogenolysis in organic synthesis . [ 1 ] This dark brown powder is commercially available. The oxide itself is not an active catalyst, but it becomes active... | https://en.wikipedia.org/wiki/PtO2 |
Platinum diselenide is a transition metal dichalcogenide with the formula PtSe 2 . It is a layered substance that can be split into layers down to three atoms thick. PtSe 2 can behave as a metalloid or as a semiconductor depending on the thickness.
Minozzi was the first to report synthesising platinum diselenide from ... | https://en.wikipedia.org/wiki/PtSe2 |
Ptaquiloside is a norsesquiterpene glucoside produced by bracken ferns (majorly Pteridium aquilinum ) during metabolism . It is identified to be the main carcinogen of the ferns and to be responsible for their biological effects, such as haemorrhagic disease and bright blindness in livestock and oesophageal , gastric c... | https://en.wikipedia.org/wiki/Ptaquiloside |
A pteridophyte is a vascular plant (with xylem and phloem ) that reproduces by means of spores . Because pteridophytes produce neither flowers nor seeds , they are sometimes referred to as " cryptogams ", meaning that their means of reproduction is hidden. They are also the ancestors of the plants we see today.
Ferns ... | https://en.wikipedia.org/wiki/Pteridophyte |
The pterobranchia mitochondrial code (translation table 24 ) is a genetic code used by the mitochondrial genome of Rhabdopleura compacta ( Pterobranchia ). The Pterobranchia are one of the two groups in the Hemichordata which together with the Echinodermata and Chordata form the three major lineages of deuterostomes . ... | https://en.wikipedia.org/wiki/Pterobranchia_mitochondrial_code |
Pteroma pendula , the oil palm bagworm or simply bagworm , is a species of bagworm moth found in East and Southeast Asia that infests oil palm plantations. [ 1 ] [ 2 ] [ 3 ]
Pteroma pendula is among most economically damaging pest of oil palm plantations in Malaysia and Indonesia, along with Metisa plana . [ 4 ] [ 5 ]... | https://en.wikipedia.org/wiki/Pteroma_pendula |
The table of chords , created by the Greek astronomer, geometer, and geographer Ptolemy in Egypt during the 2nd century AD, is a trigonometric table in Book I, chapter 11 of Ptolemy's Almagest , [ 1 ] a treatise on mathematical astronomy . It is essentially equivalent to a table of values of the sine function. It was... | https://en.wikipedia.org/wiki/Ptolemy's_table_of_chords |
In Euclidean geometry , Ptolemy's theorem is a relation between the four sides and two diagonals of a cyclic quadrilateral (a quadrilateral whose vertices lie on a common circle). The theorem is named after the Greek astronomer and mathematician Ptolemy (Claudius Ptolemaeus). [ 1 ] Ptolemy used the theorem as an aid to... | https://en.wikipedia.org/wiki/Ptolemy's_theorem |
Ptychography (/t(ʌ)ɪˈkogræfi/ t(a)i-KO-graf-ee) [ 1 ] is a computational method of microscopic imaging . [ 2 ] [ 3 ] It generates images by processing many coherent interference patterns that have been scattered from an object of interest. Its defining characteristic is translational invariance , which means that the i... | https://en.wikipedia.org/wiki/Ptychography |
Plutonium carbide comes in several stoichiometries (PuC and Pu 2 C 3 ). [ 1 ] It can be used as a nuclear fuel for nuclear reactors in conjunction with uranium carbide . The mixture is also labeled as uranium-plutonium carbide (UPuC).
This inorganic compound –related article is a stub . You can help Wikipedia by expan... | https://en.wikipedia.org/wiki/Pu2C3 |
Plutonium arsenide is a binary inorganic compound of plutonium and arsenic with the formula PuAs.
Fusion of stoichiometric amounts of pure substances in a vacuum or helium atmosphere. [ 1 ] The reaction is exothermic:
Passing arsine through heated plutonium hydride :
Plutonium arsenide forms black or dark gray cryst... | https://en.wikipedia.org/wiki/PuAs |
Plutonium(III) bromide is an inorganic salt of bromine and plutonium with the formula PuBr 3 . This radioactive green solid has few uses, however its crystal structure is often used as a structural archetype in crystallography .
The PuBr 3 crystal structure was first published in 1948 by William Houlder Zachariasen . ... | https://en.wikipedia.org/wiki/PuBr3 |
Plutonium carbide comes in several stoichiometries (PuC and Pu 2 C 3 ). [ 1 ] It can be used as a nuclear fuel for nuclear reactors in conjunction with uranium carbide . The mixture is also labeled as uranium-plutonium carbide (UPuC).
This inorganic compound –related article is a stub . You can help Wikipedia by expan... | https://en.wikipedia.org/wiki/PuC |
Plutonium(III) chloride is a chemical compound with the formula PuCl 3 . This ionic plutonium salt can be prepared by reacting the metal with hydrochloric acid .
Plutonium atoms in crystalline PuCl 3 are 9 coordinate, and the structure is tricapped trigonal prismatic . It crystallizes as the trihydrate, and forms lave... | https://en.wikipedia.org/wiki/PuCl3 |
Plutonium fluoride
Plutonium hexafluoride
Plutonium(III) fluoride or plutonium trifluoride is the chemical compound composed of plutonium and fluorine with the formula PuF 3 . This salt forms violet crystals. Plutonium(III) fluoride has the LaF 3 structure where the coordination around the plutonium atoms is complex ... | https://en.wikipedia.org/wiki/PuF3 |
Plutonium(IV) fluoride is a chemical compound with the formula PuF 4 . This salt is generally a brown solid but can appear a variety of colors depending on the grain size, purity, moisture content, lighting, and presence of contaminants. [ 4 ] [ 5 ] Its primary use in the United States has been as an intermediary produ... | https://en.wikipedia.org/wiki/PuF4 |
Plutonium tetrafluoride
Plutonium hexafluoride is the highest fluoride of plutonium , and is of interest for laser enrichment of plutonium, in particular for the production of pure plutonium-239 from irradiated uranium. This isotope of plutonium is needed to avoid premature ignition of low-mass nuclear weapon designs... | https://en.wikipedia.org/wiki/PuF6 |
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/PuO2 |
Plutonium silicide is a binary inorganic compound of plutonium and silicon with the chemical formula PuSi. [ 2 ] [ 3 ] [ 4 ] The compound forms gray crystals.
Reaction of plutonium dioxide and silicon carbide :
Reaction of plutonium trifluoride with silicon:
Plutonium silicide forms gray crystals of orthorhombic cry... | https://en.wikipedia.org/wiki/PuSi |
PubChem is a database of chemical molecules and their activities against biological assays . The system is maintained by the National Center for Biotechnology Information (NCBI), a component of the National Library of Medicine , which is part of the United States National Institutes of Health (NIH). PubChem can be acce... | https://en.wikipedia.org/wiki/PubChem |
PubGene AS is a bioinformatics company located in Oslo , Norway and is the daughter company of PubGene Inc.
In 2001, PubGene founders demonstrated one of the first [ 1 ] applications of text mining to research in biomedicine (i.e., biomedical text mining ). They went on to create the PubGene public search engine, [ 2 ... | https://en.wikipedia.org/wiki/PubGene |
Public Interest Research Group in Michigan ( PIRGIM ) is a non-profit organization that is part of the state PIRG organizations.
PIRGIM has a history of working on a variety of issues, such as cleaning Michigan's waterways, [ 1 ] toy safety, [ 2 ] and chemical safety. [ 3 ]
The PIRGs emerged in the early 1970s on U.S... | https://en.wikipedia.org/wiki/Public_Interest_Research_Group_in_Michigan |
Public Law 114-216 is a federal law of the United States that regulates GMO food labeling. It was enacted on July 29, 2016 when President Obama signed then Senate Bill 764 (S.764) and is codified at 7 U.S.C. ch. 38, subch. V and VI . While the law is officially termed A bill to reauthorize and amend the National Sea Gr... | https://en.wikipedia.org/wiki/Public_Law_114-216 |
A public address system (or PA system ) is an electronic system comprising microphones, amplifiers, loudspeakers, and related equipment. It increases the apparent volume (loudness) of a human voice, musical instrument, or other acoustic sound source or recorded sound or music. PA systems are used in any public venue th... | https://en.wikipedia.org/wiki/Public_address_system |
Public Analysts are scientists in the British Isles whose principal task is to ensure the safety and correct description of food by testing for compliance with legislation. [ 1 ] Most Public Analysts are also Agricultural Analysts who carry out similar work on animal feedingstuffs and fertilisers. [ 2 ] Nowadays this i... | https://en.wikipedia.org/wiki/Public_analyst |
Public health laboratories (PHLs) or National Public Health Laboratories (NPHL) are governmental reference laboratories that protect the public against diseases and other health hazards. The 2005 International Health Regulations came into force in June 2007, with 196 binding countries that recognised that certain publi... | https://en.wikipedia.org/wiki/Public_health_laboratory |
Public interest design is a human-centered [ 1 ] and participatory design practice [ 2 ] that places emphasis on the “ triple bottom line ” of sustainable design that includes ecological, economic, and social issues and on designing products, structures, and systems that address issues such as economic development and ... | https://en.wikipedia.org/wiki/Public_interest_design |
In telecommunication, a public land mobile network ( PLMN ) is a combination of wireless communication services offered by a specific operator in a specific country. [ 1 ] [ 2 ] A PLMN typically consists of several cellular technologies like GSM / 2G , UMTS / 3G , LTE / 4G , NR/5G, offered by a single operator within a... | https://en.wikipedia.org/wiki/Public_land_mobile_network |
The public switched telephone network ( PSTN ) is the aggregate of the world's telephone networks that are operated by national, regional, or local telephony operators. It provides infrastructure and services for public telephony . The PSTN consists of telephone lines , fiber-optic cables , microwave transmission links... | https://en.wikipedia.org/wiki/Public_switched_telephone_network |
Public works are a broad category of infrastructure projects, financed and procured by a government body for recreational, employment, and health and safety uses in the greater community . They include public buildings ( municipal buildings , schools , and hospitals ), transport infrastructure ( roads , railroads , bri... | https://en.wikipedia.org/wiki/Public_works |
PubMeth is a database that contains information about DNA hypermethylation in cancer. It can be queried either by searching a list of genes, or cancer (sub)types.
It was created at the lab for bioinformatics and computational genomics in the Department of Molecular Biotechnology, Faculty of Bioscience Engineering at G... | https://en.wikipedia.org/wiki/Pubmeth |
Puddling is the process of converting pig iron to bar (wrought) iron in a coal fired reverberatory furnace . It was developed in England during the 1780s. The molten pig iron was stirred in a reverberatory furnace, in an oxidizing environment to burn the carbon, resulting in wrought iron . [ 1 ] It was one of the mos... | https://en.wikipedia.org/wiki/Puddling_(metallurgy) |
In organophosphorus chemistry , the Pudovik reaction is a method for preparing α-aminomethylphosphonates . Under basic conditions, the phosphorus–hydrogen bond of a dialkylphosphite , (RO) 2 P(O)H, adds across the carbon–nitrogen double bond of an imine (a hydrophosphonylation reaction). [ 1 ] The reaction is closely r... | https://en.wikipedia.org/wiki/Pudovik_reaction |
In mathematics , Pugh's closing lemma is a result that links periodic orbit solutions of differential equations to chaotic behaviour . It can be formally stated as follows:
Pugh's closing lemma means, for example, that any chaotic set in a bounded continuous dynamical system corresponds to a periodic orbit in a differ... | https://en.wikipedia.org/wiki/Pugh's_closing_lemma |
A pugmill , pug mill , or commonly just pug , is a machine in which clay or other materials are extruded in a plastic state or a similar machine for the trituration of ore. [ 1 ] Industrial applications are found in pottery , bricks , cement and some parts of the concrete and asphalt mixing processes. A pugmill may be ... | https://en.wikipedia.org/wiki/Pugmill |
The Pugwash Conferences on Science and World Affairs is an international organization that brings together scholars and public figures to work toward reducing the danger of armed conflict and to seek solutions to global security threats. It was founded in 1957 by Joseph Rotblat and Bertrand Russell in Pugwash, Nova Sco... | https://en.wikipedia.org/wiki/Pugwash_Conferences_on_Science_and_World_Affairs |
The Pujiang line ( simplified Chinese : 浦江线 ; traditional Chinese : 浦江線 ; pinyin : Pǔjiāng Xiàn ) is an automated, driverless, rubber-tired Shanghai Metro line in the town of Pujiang in the Shanghainese district of Minhang . It was originally conceived as phase 3 of Shanghai Metro line 8 , but afterwards was constructe... | https://en.wikipedia.org/wiki/Pujiang_line |
In mathematics , a pullback is either of two different, but related processes: precomposition and fiber-product. Its dual is a pushforward .
Precomposition with a function probably provides the most elementary notion of pullback: in simple terms, a function f {\displaystyle f} of a variable y , {\displaystyle y,} whe... | https://en.wikipedia.org/wiki/Pullback |
Let ϕ : M → N {\displaystyle \phi :M\to N} be a smooth map between smooth manifolds M {\displaystyle M} and N {\displaystyle N} . Then there is an associated linear map from the space of 1-forms on N {\displaystyle N} (the linear space of sections of the cotangent bundle ) to the space of 1-forms on M {\displaystyle M}... | https://en.wikipedia.org/wiki/Pullback_(differential_geometry) |
A pulley is a wheel on an axle or shaft enabling a taut cable or belt passing over the wheel to move and change direction, or transfer power between itself and a shaft. A sheave or pulley wheel is a pulley using an axle supported by a frame or shell ( block ) to guide a cable or exert force.
A pulley may have a groove... | https://en.wikipedia.org/wiki/Pulley |
Pullulan is a polysaccharide consisting of maltotriose units, also known as α-1,4- ;α-1,6- glucan '. Three glucose units in maltotriose are connected by an α-1,4 glycosidic bond , whereas consecutive maltotriose units are connected to each other by an α-1,6 glycosidic bond . Pullulan is produced from starch by the fun... | https://en.wikipedia.org/wiki/Pullulan |
Pullulan bioconjugates are systems that use pullulan as a scaffold to attach biological materials to, such as drugs. These systems can be used to enhance the delivery of drugs to specific environments or the mechanism of delivery. These systems can be used in order to deliver drugs in response to stimuli, create a more... | https://en.wikipedia.org/wiki/Pullulan_bioconjugate |
X-ray pulsar-based navigation and timing (XNAV) or simply pulsar navigation is a navigation technique whereby the periodic X-ray signals emitted from pulsars are used to determine the location of a vehicle, such as a spacecraft in deep space. A vehicle using XNAV would compare received X-ray signals with a database of ... | https://en.wikipedia.org/wiki/Pulsar-based_navigation |
A pulsar clock is a clock which depends on counting radio pulses emitted by pulsars .
The first pulsar clock in the world was installed in St. Catherine's Church, Gdańsk , Poland, in 2011. [ 1 ] It was the first clock to count the time using a signal source outside the Solar System , and represents the second type of ... | https://en.wikipedia.org/wiki/Pulsar_clock |
In fluid dynamics , a flow with periodic variations is known as pulsatile flow , or as Womersley flow . The flow profiles was first derived by John R. Womersley (1907–1958) in his work with blood flow in arteries . [ 1 ] The cardiovascular system of chordate animals is a very good example where pulsatile flow is found,... | https://en.wikipedia.org/wiki/Pulsatile_flow |
Pulsatile secretion is a biochemical phenomenon observed in a wide variety of cell and tissue types, in which chemical products are secreted in a regular temporal pattern. The most common cellular products observed to be released in this manner are intercellular signaling molecules such as hormones or neurotransmitte... | https://en.wikipedia.org/wiki/Pulsatile_secretion |
Pulsation reactor technology is a thermal procedure for manufacturing fine powders with precisely defined properties.
Pulsation reactor technology is a thermal procedure with a special functional principle that results in reaction parameters and a reaction medium, and which ultimately leads to other property parameter... | https://en.wikipedia.org/wiki/Pulsation_reactor |
A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity. It combines the features of pulse radars and continuous-wave radars , which were formerly separate due to the complex... | https://en.wikipedia.org/wiki/Pulse-Doppler_radar |
Pulse-chase analysis (PCA) is used to study the life cycles of proteins. Pulse-chase analysis experiments use radioactive and cytotoxic labels to "tag" proteins. Commonly used methods include treating cells with cycloheximide (CHX) to stop protein synthesis or radioisotopic amino acids or proteins such as green fluore... | https://en.wikipedia.org/wiki/Pulse-chase_analysis |
In physics , a pulse is a generic term describing a single disturbance that moves through a transmission medium . This medium may be vacuum (in the case of electromagnetic radiation ) or matter , and may be indefinitely large or finite.
Consider a pulse moving through a medium - perhaps through a rope or a slinky . Wh... | https://en.wikipedia.org/wiki/Pulse_(physics) |
Pulse electrolysis is an alternate electrolysis method that utilises a pulsed direct current to initiate non-spontaneous chemical reactions . [ 1 ] [ 2 ] [ 3 ] Also known as pulsed direct current (PDC) electrolysis, the increased number of variables that it introduces to the electrolysis method can change the applicati... | https://en.wikipedia.org/wiki/Pulse_electrolysis |
Pulse labelling is a biochemistry technique of identifying the presence of a target molecule by labeling a sample with a radioactive compound. This is mainly done to identify the stage at which the messenger RNA is being produced in a cell . [ 1 ]
This biochemistry article is a stub . You can help Wikipedia by expandi... | https://en.wikipedia.org/wiki/Pulse_labelling |
In Fourier transform NMR spectroscopy and imaging , a pulse sequence describes a series of radio frequency pulses applied to the sample, such that the free induction decay is related to the characteristic frequencies of the desired signals. After applying a Fourier transform , the signal can be represented in the frequ... | https://en.wikipedia.org/wiki/Pulse_sequence |
The pulse vaccination strategy is a method used to eradicate an epidemic by repeatedly vaccinating a group at risk, over a defined age range, until the spread of the pathogen has been stopped. It is most commonly used during measles and polio epidemics to quickly stop the spread and contain the outbreak. [ 1 ] [ 2 ]
W... | https://en.wikipedia.org/wiki/Pulse_vaccination_strategy |
Pulsed-field gel electrophoresis ( PFGE ) is a technique used for the separation of large DNA molecules by applying an electric field that periodically changes direction to a gel matrix. [ 1 ] [ 2 ] Unlike standard agarose gel electrophoresis , which can separate DNA fragments of up to 50 kb, PFGE resolves fragments up... | https://en.wikipedia.org/wiki/Pulsed-field_gel_electrophoresis |
Pulsed-power water treatment is the process of using pulsed , electro-magnetic fields into cooling water to control scaling , biological growth, and corrosion. The process does not require the use of chemicals and helps eliminate environmental and health issues associated with the use and life-cycle management of chemi... | https://en.wikipedia.org/wiki/Pulsed-power_water_treatment |
In astronomy, Pulsed accretion is the periodic modulation in accretion rate of young stellar objects in binary systems , producing a periodic pulse in the observed infrared light curves of T Tauri stars . [ 1 ]
In double stars in young stellar objects , a protoplanetary disk is formed around each star, accreted from n... | https://en.wikipedia.org/wiki/Pulsed_accretion |
Pulsed columns are a type of liquid-liquid extraction equipment; [ 1 ] examples of this class of extraction equipment is used at the BNFL plant THORP .
Special use in nuclear industries for fuel reprocessing, where spent fuel from reactors is subjected to solvent extraction. A pulsation is created using air by a pulse... | https://en.wikipedia.org/wiki/Pulsed_columns |
Pulsed electron paramagnetic resonance (EPR) is an electron paramagnetic resonance technique that involves the alignment of the net magnetization vector of the electron spins in a constant magnetic field . This alignment is perturbed by applying a short oscillating field, usually a microwave pulse. One can then measure... | https://en.wikipedia.org/wiki/Pulsed_electron_paramagnetic_resonance |
A pulsed field gradient is a short, timed pulse with spatial-dependent field intensity. Any gradient is identified by four characteristics: axis, strength, shape and duration.
Pulsed field gradient (PFG) techniques are key to magnetic resonance imaging , spatially selective spectroscopy and studies of diffusion via di... | https://en.wikipedia.org/wiki/Pulsed_field_gradient |
A pulsed field magnet is a strong electromagnet which is powered by a brief pulse of electric current through its windings rather than a continuous current, producing a brief but strong pulse of magnetic field . Pulsed field magnets are used in research in fields such as materials science to study the effect of strong... | https://en.wikipedia.org/wiki/Pulsed_field_magnet |
The Pummerer rearrangement is an organic reaction whereby an alkyl sulfoxide rearranges to an α- acyloxy – thioether (mono thioacetal -ester) in the presence of acetic anhydride . [ 1 ] [ 2 ] [ 3 ]
The stoichiometry of the reaction is:
Aside from acetic anhydride , trifluoroacetic anhydride and trifluoromethanesulfon... | https://en.wikipedia.org/wiki/Pummerer_rearrangement |
The Pump-areometer was an early hydrometer (a variant of the syphon-hydrometer ), [ 1 ] credited to Floris Nollet . [ 2 ]
The principle is an inverted glass tube with one leg in each of two liquids, the upper end being connected to a pump. Once sufficient air is removed from the pipe, the liquids rise in both legs, i... | https://en.wikipedia.org/wiki/Pump-areometer |
The Pumpherston retort (also known as the Bryson retort ) was a type of oil-shale retort used in Britain at the end of 19th and beginning of 20th century. It marked separation of the oil-shale industry from the coal industry as it was designed specifically for oil-shale retorting. [ 1 ] The retort is named after Pumphe... | https://en.wikipedia.org/wiki/Pumpherston_retort |
In sound recording and reproduction , and music, pumping or gain pumping is a creative misuse of compression , the "audible unnatural level changes associated primarily with the release of a compressor." [ 1 ] There is no correct way to produce pumping, and according to Alex Case, the effect may result from selecting "... | https://en.wikipedia.org/wiki/Pumping_(audio) |
In the theory of formal languages , the pumping lemma for regular languages is a lemma that describes an essential property of all regular languages . Informally, it says that all sufficiently long strings in a regular language may be pumped —that is, have a middle section of the string repeated an arbitrary number of ... | https://en.wikipedia.org/wiki/Pumping_lemma_for_regular_languages |
A pumpjack is the overground drive for a reciprocating piston pump in an oil well . [ 1 ]
It is used to mechanically lift liquid out of the well if there is not enough bottom hole pressure for the liquid to flow all the way to the surface. The arrangement is often used for onshore wells. Pumpjacks are common in oil-ri... | https://en.wikipedia.org/wiki/Pumpjack |
PumpLinx is a 3-D computational fluid dynamics (CFD) software developed for the analysis of fluid pumps, motors, compressors, valves, propellers, hydraulic systems, and other fluid devices with rotating or sliding components.
The software imports 3-D geometry from CAD data in the form of STL files. [ 1 ] It has geomet... | https://en.wikipedia.org/wiki/Pumplinx |
Pump–probe microscopy is a non-linear optical imaging modality used in femtochemistry to study chemical reactions . It generates high-contrast images from endogenous non-fluorescent targets. It has numerous applications, including materials science , medicine , and art restoration .
The classic method of nonlinear abs... | https://en.wikipedia.org/wiki/Pump–probe_microscopy |
A punched card (also punch card [ 1 ] or punched-card [ 2 ] ) is a stiff paper-based medium used to store digital information via the presence or absence of holes in predefined positions. Developed over the 18th to 20th centuries, punched cards were widely used for data processing , the control of automated machines , ... | https://en.wikipedia.org/wiki/Punched_card |
A computer punched card reader or just computer card reader is a computer input device used to read computer programs in either source or executable form and data from punched cards . A computer card punch is a computer output device that punches holes in cards. Sometimes computer punch card readers were combined with ... | https://en.wikipedia.org/wiki/Punched_card_input/output |
Punched tape or perforated paper tape is a form of data storage that consists of a long strip of paper through which small holes are punched. It was developed from and was subsequently used alongside punched cards , the difference being that the tape is continuous.
Punched cards, and chains of punched cards, were used... | https://en.wikipedia.org/wiki/Punched_tape |
Punctuality is the characteristic of completing a required task or fulfilling an obligation before or at a previously designated time. based on job requirements and or daily operations [ 1 ] " Punctual " is often used synonymously with " on time ".
An opposite characteristic is tardiness .
Each culture tends to have... | https://en.wikipedia.org/wiki/Punctuality |
Punctuated gradualism is a microevolutionary hypothesis that refers to a species that has "relative stasis over a considerable part of its total duration [and] underwent periodic, relatively rapid, morphologic change that did not lead to lineage branching". It is one of the three common models of evolution .
While th... | https://en.wikipedia.org/wiki/Punctuated_gradualism |
In topology , puncturing a manifold is removing a finite set of points from that manifold. [ 1 ] The set of points can be small as a single point. In this case, the manifold is known as once-punctured . With the removal of a second point, it becomes twice-punctured , and so on.
Examples of punctured manifolds include ... | https://en.wikipedia.org/wiki/Puncture_(topology) |
Puncture resistance denotes the relative ability of a material or object to inhibit the intrusion of a foreign object. This is defined by a test method , regulation, or technical specification . It can be measured in several ways ranging from a slow controlled puncture to a rapid impact of a sharp object or a rounde... | https://en.wikipedia.org/wiki/Puncture_resistance |
In coding theory , puncturing is the process of removing some of the parity bits after encoding with an error-correction code . This has the same effect as encoding with an error-correction code with a higher rate, or less redundancy. However, with puncturing the same decoder can be used regardless of how many bits h... | https://en.wikipedia.org/wiki/Punctured_code |
The Punnett square is a square diagram that is used to predict the genotypes of a particular cross or breeding experiment. It is named after Reginald C. Punnett , who devised the approach in 1905. [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 7 ] [ 8 ] The diagram is used by biologists to determine the probability of an offspring having a... | https://en.wikipedia.org/wiki/Punnett_square |
Punya Thitimajshima (9 November 1955 – 9 May 2006), a Thai professor in the department of telecommunications engineering at King Mongkut's Institute of Technology at Ladkrabang , was the co-inventor with Claude Berrou and Alain Glavieux of a groundbreaking coding scheme called turbo codes .
Thitimajshima was educated ... | https://en.wikipedia.org/wiki/Punya_Thitimajshima |
Puppet-rearing is a method of breeding birds in captivity for reintroduction into the wild. Chicks are fed using puppets that simulate adults of their species, worn by caregivers whose bodies are hidden from view, thereby reducing the birds' direct contact with humans. [ 1 ] [ 2 ] [ 3 ]
Through imprinting , birds asso... | https://en.wikipedia.org/wiki/Puppet-rearing |
Purchasing is the procurement process a business or organization uses to acquire goods or services to accomplish its goals. Although there are several organizations that attempt to set standards in the purchasing process, processes can vary greatly between organizations.
Purchasing is part of the wider procurement pro... | https://en.wikipedia.org/wiki/Purchasing |
Purchasing power parity ( PPP ) [ 1 ] is a measure of the price of specific goods in different countries and is used to compare the absolute purchasing power of the countries' currencies . PPP is effectively the ratio of the price of a market basket at one location divided by the price
of the basket of goods at a diff... | https://en.wikipedia.org/wiki/Purchasing_power_parity |
In solid mechanics , pure bending (also known as the theory of simple bending ) is a condition of stress where a bending moment is applied to a beam without the simultaneous presence of axial , shear , or torsional forces .
Pure bending occurs only under a constant bending moment ( M ) since the shear force ( V ), whic... | https://en.wikipedia.org/wiki/Pure_bending |
A pure fusion weapon is a hypothetical hydrogen bomb design that does not need a fission "primary" explosive to ignite the fusion of deuterium and tritium , two heavy isotopes of hydrogen used in fission-fusion thermonuclear weapons . Such a weapon would require no fissile material and would therefore be much easier to... | https://en.wikipedia.org/wiki/Pure_fusion_weapon |
Pure inductive logic ( PIL ) is the area of mathematical logic concerned with the philosophical and mathematical foundations of probabilistic inductive reasoning . It combines classical predicate logic and probability theory ( Bayesian inference ). Probability values are assigned to sentences of a first-order relationa... | https://en.wikipedia.org/wiki/Pure_inductive_logic |
Pure mathematics is the study of mathematical concepts independently of any application outside mathematics . These concepts may originate in real-world concerns, and the results obtained may later turn out to be useful for practical applications, but pure mathematicians are not primarily motivated by such applications... | https://en.wikipedia.org/wiki/Pure_mathematics |
In the branches of mathematical logic known as proof theory and type theory , a pure type system ( PTS ), previously known as a generalized type system ( GTS ), is a form of typed lambda calculus that allows an arbitrary number of sorts and dependencies between any of these. The framework can be seen as a generalisatio... | https://en.wikipedia.org/wiki/Pure_type_system |
In fire and explosion prevention engineering, purging refers to the introduction of an inert (i.e. non-combustible) purge gas into a closed system (e.g. a container or a process vessel) to prevent the formation of an ignitable atmosphere. Purging relies on the principle that a combustible (or flammable) gas is able to... | https://en.wikipedia.org/wiki/Purging_(gas) |
In game theory , the purification theorem was contributed by Nobel laureate John Harsanyi in 1973. [ 1 ] The theorem justifies a puzzling aspect of mixed strategy Nash equilibria : each player is wholly indifferent between each of the actions he puts non-zero weight on, yet he mixes them so as to make every other playe... | https://en.wikipedia.org/wiki/Purification_theorem |
Purified water is water that has been mechanically filtered or processed to remove impurities and make it suitable for use. Distilled water was, formerly, the most common form of purified water, but, in recent years, water is more frequently purified by other processes including capacitive deionization , reverse osmosi... | https://en.wikipedia.org/wiki/Purified_water |
Purine analogues are antimetabolites that mimic the structure of metabolic purines .
Purine antimetabolites are commonly used to treat cancer by interfering with DNA replication. [ 1 ]
This biochemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Purine_analogue |
Purine metabolism refers to the metabolic pathways to synthesize and break down purines that are present in many organisms.
Purines are biologically synthesized as nucleotides and in particular as ribotides, i.e. bases attached to ribose 5-phosphate . Both adenine and guanine are derived from the nucleotide inosine mo... | https://en.wikipedia.org/wiki/Purine_metabolism |
The Purine Nucleotide Cycle is a metabolic pathway in protein metabolism requiring the amino acids aspartate and glutamate . The cycle is used to regulate the levels of adenine nucleotides , in which ammonia and fumarate are generated. [ 2 ] AMP converts into IMP and the byproduct ammonia. IMP converts to S-AMP ( aden... | https://en.wikipedia.org/wiki/Purine_nucleotide_cycle |
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