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Petroleum geochemistry is a branch of geochemistry (the application of chemical concepts to understand geological systems) which deals specifically with petroleum and its origin, generation, and accumulation, as well as its extraction, refinement, and use. [ 1 ] [ 2 ] Petroleum, also known as crude oil, is a solid , li... | https://en.wikipedia.org/wiki/Petroleum_geochemistry |
Petroleum jelly , petrolatum ( / ˌ p ɛ t r ə ˈ l eɪ t ə m / ), white petrolatum , soft paraffin , or multi-hydrocarbon , CAS number 8009-03-8, is a semi-solid mixture of hydrocarbons (with carbon numbers mainly higher than 25), [ 1 ] originally promoted as a topical ointment for its healing properties. [ 2 ] Vaseline h... | https://en.wikipedia.org/wiki/Petroleum_jelly |
Petroleum microbiology is a branch of microbiology that deals with the study of microorganisms that can metabolize or alter crude or refined petroleum products . These microorganisms, also called hydrocarbonoclastic microorganisms, can degrade hydrocarbons and, include a wide distribution of bacteria, methanogenic arch... | https://en.wikipedia.org/wiki/Petroleum_microbiology |
Petroleum naphtha is an intermediate hydrocarbon liquid stream derived from the refining of crude oil [ 1 ] [ 2 ] [ 3 ] with CAS -no 64742-48-9. [ 4 ] It is most usually desulfurized and then catalytically reformed , which rearranges or restructures the hydrocarbon molecules in the naphtha as well as breaking some of t... | https://en.wikipedia.org/wiki/Petroleum_naphtha |
Petroleum products are materials derived from crude oil ( petroleum ) as it is processed in oil refineries . Unlike petrochemicals , which are a collection of well-defined usually pure organic compounds, petroleum products are complex mixtures. [ 1 ] Most petroleum is converted into petroleum products, which include se... | https://en.wikipedia.org/wiki/Petroleum_product |
Petroleum production engineering is a subset of petroleum engineering .
Petroleum production engineers design and select subsurface equipment to produce oil and gas well fluids . [ 1 ] They often are degreed as petroleum engineers , although they may come from other technical disciplines (e.g., mechanical engineering ... | https://en.wikipedia.org/wiki/Petroleum_production_engineering |
A hydrocarbon resin is a C5/C9 aromatic hydrocarbon that is used in industrial applications. It has a tackifying effect and is suitable for use in paint , printing ink , adhesives , rubber and other areas where tackiness is required. [ 1 ]
Generally, the petroleum resins are not used independently, but have to be used... | https://en.wikipedia.org/wiki/Petroleum_resin |
The petrolingual ligament lies at the posteroinferior aspect of the lateral wall of the cavernous sinus and marks the point at which the internal carotid artery enters the cavernous sinus .
Anatomically, the petrolingual ligament demarcates two of the segments of the internal carotid artery:
For surgeons and radiolog... | https://en.wikipedia.org/wiki/Petrolingual_ligament |
Petrophysics (from the Greek πέτρα, petra , "rock" and φύσις, physis , "nature") is the study of physical and chemical rock properties and their interactions with fluids . [ 1 ]
A major application of petrophysics is in studying reservoirs for the hydrocarbon industry . Petrophysicists work together with reservoir en... | https://en.wikipedia.org/wiki/Petrophysics |
Petrosix is the world's largest surface oil shale pyrolysis retort with an 11 metres (36 ft) diameter vertical shaft kiln , operational since 1992. It is located in São Mateus do Sul , Brazil , and it is owned and operated by the Brazil energy company Petrobras . Petrosix means also the Petrosix process, an externally ... | https://en.wikipedia.org/wiki/Petrosix |
In differential geometry and theoretical physics , the Petrov classification (also known as Petrov–Pirani–Penrose classification) describes the possible algebraic symmetries of the Weyl tensor at each event in a Lorentzian manifold .
It is most often applied in studying exact solutions of Einstein's field equations , ... | https://en.wikipedia.org/wiki/Petrov_classification |
In quantum information theory , a mix of quantum mechanics and information theory , the Petz recovery map can be thought of a quantum analog of Bayes' theorem . Proposed by Dénes Petz , [ 1 ] the Petz recovery map is a quantum channel associated with a given quantum channel and quantum state. This recovery map is desig... | https://en.wikipedia.org/wiki/Petz_recovery_map |
Pewter ( / ˈ p juː t ər / ) is a malleable metal alloy consisting of tin (85–99%), antimony (approximately 5–10%), copper (2%), [ 1 ] bismuth , [ 2 ] and sometimes silver . [ 3 ] In the past, it was an alloy of tin and lead , but most modern pewter, in order to prevent lead poisoning , is not made with lead. Pewter has... | https://en.wikipedia.org/wiki/Pewter |
The Pfafstetter Coding System is a hierarchical method of hydrologically coding river basins . It was developed by the Brazilian engineer Otto Pfafstetter [ pt ] in 1989. [ 1 ] It is designed such that topological information is embedded in the code, which makes it easy to determine whether an event in one river basin ... | https://en.wikipedia.org/wiki/Pfafstetter_Coding_System |
The Pfeiffer effect is an optical phenomenon whereby the presence of an optically active compound influences the optical rotation of a racemic mixture of a second compound.
Racemic mixtures do not rotate plane polarized light , but the equilibrium concentration of the two enantiomers can shift from unity in the presen... | https://en.wikipedia.org/wiki/Pfeiffer_effect |
The Pfitzinger reaction (also known as the Pfitzinger-Borsche reaction ) is the chemical reaction of isatin with base and a carbonyl compound to yield substituted quinoline -4- carboxylic acids . [ 1 ] [ 2 ]
Several reviews have been published. [ 3 ] [ 4 ] [ 5 ]
The reaction of isatin with a base such as potassium hy... | https://en.wikipedia.org/wiki/Pfitzinger_reaction |
The Pfitzner–Moffatt oxidation , sometimes referred to as simply the Moffatt oxidation , is a chemical reaction for the oxidation of primary and secondary alcohols to aldehydes and ketones , respectively. The oxidant is a combination of dimethyl sulfoxide (DMSO) and dicyclohexylcarbodiimide (DCC). The reaction was fi... | https://en.wikipedia.org/wiki/Pfitzner–Moffatt_oxidation |
The Pfizer Award is awarded annually by the History of Science Society "in recognition of an outstanding book dealing with the history of science " that was "published in English during a period of three calendar years immediately preceding the year of competition." [ 1 ] | https://en.wikipedia.org/wiki/Pfizer_Award |
The Pfizer Award in Enzyme Chemistry , formerly known as the Paul-Lewis Award in Enzyme Chemistry [ 1 ] was established in 1945. Consisting of a gold medal and honorarium, its purpose is to stimulate fundamental research in enzyme chemistry by scientists not over forty years of age. The award is administered by the Div... | https://en.wikipedia.org/wiki/Pfizer_Award_in_Enzyme_Chemistry |
Pfu DNA polymerase is an enzyme found in the hyperthermophilic archaeon Pyrococcus furiosus , where it functions to copy the organism's DNA during cell division ( thermostable DNA polymerase ). In the laboratory setting, Pfu is used to amplify DNA in the polymerase chain reaction (PCR), where the enzyme serves the cent... | https://en.wikipedia.org/wiki/Pfu_DNA_polymerase |
Pentaphenylphosphorus is an organic phosphorane containing five phenyl groups connected to a central phosphorus atom. The phosphorus atom is considered to be in the +5 oxidation state . The chemical formula could be written as P(C 6 H 5 ) 5 or Ph 5 P, where Ph represents the phenyl group. It was discovered and reported... | https://en.wikipedia.org/wiki/Ph5P |
PhEVER is a database of homologous gene families between viral sequences and sequences from cellular organisms . [ 1 ]
This Biological database -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/PhEVER |
Iodobenzene dichloride (PhICl 2 ) is a complex of iodobenzene with chlorine . As a reagent for organic chemistry, it is used as an oxidant and chlorinating agent .
Single-crystal X-ray crystallography has been used to determine its structure; as can be predicted by VSEPR theory , it adopts a T-shaped geometry about th... | https://en.wikipedia.org/wiki/PhICl2 |
Phage immunoprecipitation sequencing (PhIP-Seq) is method that combines barcoded DNA high-throughput sequencing and proteomics to determine the levels of binding of antibodies to epitopes . It has been used to study the autoantibody repertoire of autoimmune diseases like multiple sclerosis , type 2 diabetes and rheumat... | https://en.wikipedia.org/wiki/PhIP-Seq |
PhTx-1 is a toxic fraction isolated from the venom of the Brazilian wandering spider Phoneutria nigriventer .
PhTx-1 has as its main toxin PnTx-1, with a molecular mass of 8,594.6 Da, composed of 77 aminoacid residues, 14 of which are cysteines. [ 1 ] PnTx-1, also known as Tx1, exerts an inhibitory effect on neuronal ... | https://en.wikipedia.org/wiki/PhTx-1 |
PhTx-2 is a toxic fraction of the venom of the Brazilian wandering spider Phoneutria nigriventer .
This fraction is responsible for most of the venom's effects, acts on voltage-gated ion channels , this fraction is composed of nine different peptides , of which PhTx-2-5 and PhTx-2-6 activate voltage-gated ion channels... | https://en.wikipedia.org/wiki/PhTx-2 |
Phaedon Avouris ( Greek : Φαίδων Αβούρης ; born 1945) leads IBM ’s nanoscience and nanotechnology research efforts. His research explores the application of molecular devices in computing and electronics. This includes experimental and theoretical studies on the electronics and photonics of carbon nanotubes (CNT) and g... | https://en.wikipedia.org/wiki/Phaedon_Avouris |
Phaeocystis globosa virus virophage , or PgVV , or Preplasmiviricota sp. Gezel-14T , [ 1 ] is a polinton -like virus, which are small DNA viruses that are found integrated in protist genomes. Similar to virophages , PgVV requires a helper virus to replicate . Phaeocystis globosa virus virophage has a parasitic relation... | https://en.wikipedia.org/wiki/Phaeocystis_globosa_virus_virophage |
Phaeton (alternatively Phaethon / ˈ f eɪ . ə θ ən / or Phaëton / ˈ f eɪ . ə t ən / ; from Ancient Greek : Φαέθων , romanized : Phaéthōn , pronounced [pʰa.é.tʰɔːn] ) is a hypothetical planet hypothesized by the Titius–Bode law to have existed between the orbits of Mars and Jupiter , the destruction of which supposedly l... | https://en.wikipedia.org/wiki/Phaeton_(hypothetical_planet) |
Phage-assisted continuous evolution ( PACE ) is a phage -based technique for the automated directed evolution of proteins. It relies on relating the desired activity of a target protein with the fitness of an infectious bacteriophage which carries the protein's corresponding gene. Proteins with greater desired activity... | https://en.wikipedia.org/wiki/Phage-assisted_continuous_evolution |
The Phage-ligand technology is a technology to detect, bind and remove bacteria and bacterial toxins by using highly specific bacteriophage derived proteins. [ 1 ]
The host recognition of bacteriophages occur via bacteria-binding proteins that have strong binding affinities to specific protein or carbohydrate structur... | https://en.wikipedia.org/wiki/Phage-ligand_technology |
Phage display is a laboratory technique for the study of protein–protein , protein – peptide , and protein– DNA interactions that uses bacteriophages ( viruses that infect bacteria ) to connect proteins with the genetic information that encodes them. [ 1 ] In this technique, a gene encoding a protein of interest is ins... | https://en.wikipedia.org/wiki/Phage_display |
Bacteriophages ( phages ), potentially the most numerous "organisms" on Earth , are the viruses of bacteria (more generally, of prokaryotes [ 1 ] ). Phage ecology is the study of the interaction of bacteriophages with their environments . [ 2 ]
Phages are obligate intracellular parasites meaning that they are able to ... | https://en.wikipedia.org/wiki/Phage_ecology |
Phage typing is a phenotypic method that uses bacteriophages ("phages" for short) for detecting and identifying single strains of bacteria . [ 1 ] Phages are viruses that infect bacteria and may lead to bacterial cell lysis . [ 2 ] The bacterial strain is assigned a type based on its lysis pattern. [ 3 ] Phage typing w... | https://en.wikipedia.org/wiki/Phage_typing |
A phagemid or phasmid is a DNA -based cloning vector , which has both bacteriophage and plasmid properties. [ 1 ] These vectors carry, in addition to the origin of plasmid replication, an origin of replication derived from bacteriophage. Unlike commonly used plasmids, phagemid vectors differ by having the ability to be... | https://en.wikipedia.org/wiki/Phagemid |
A phageome is a community of bacteriophages and their metagenomes localized in a particular environment, similar to a microbiome . [ 1 ] [ 2 ] Phageome is a subcategory of virome , which is all of the viruses that are associated with a host or environment. [ 3 ] The term was first used in an article by Modi et al. in 2... | https://en.wikipedia.org/wiki/Phageome |
Phagocytosis (from Ancient Greek φαγεῖν (phagein) ' to eat ' and κύτος (kytos) ' cell ' ) is the process by which a cell uses its plasma membrane to engulf a large particle (≥ 0.5 μm), giving rise to an internal compartment called the phagosome . It is one type of endocytosis . A cell that performs phagocytosis is cal... | https://en.wikipedia.org/wiki/Phagocytosis |
Phagophilia or phagophily is the behaviour of feeding on parasites . It is also an example of cleaning symbiosis . [ 1 ] [ 2 ]
Austrian arachnologist Max Beier reported on phagophilia in pseudoscorpions . Many pseudoscorpion species co-exist with packrat species, and two of them are known to feed on packrat ectoparasi... | https://en.wikipedia.org/wiki/Phagophilia |
Phagoptosis (cell death by phagocytosis) is a type of cell death caused by the cell being phagocytosed (i.e. eaten) by another cell, and therefore this form of cell death is prevented by blocking phagocytosis . [ 1 ] [ 2 ]
Phagocytosis of an otherwise-viable cell may occur because the cell is recognised as stressed, a... | https://en.wikipedia.org/wiki/Phagoptosis |
In cell biology , a phagosome is a vesicle formed around a particle engulfed by a phagocyte via phagocytosis . Professional phagocytes include macrophages , neutrophils , and dendritic cells (DCs). [ 1 ]
A phagosome is formed by the fusion of the cell membrane around a microorganism , a senescent cell or an apoptotic ... | https://en.wikipedia.org/wiki/Phagosome |
Phalanx Biotech Group was founded in 2002 as a result of collaboration between Taiwan 's Industrial Technology Research Institute ( ITRI ) and several private companies and research institutes. [ 1 ] It is a manufacturer of DNA microarrays and a provider of gene expression profiling and microRNA profiling services base... | https://en.wikipedia.org/wiki/Phalanx_Biotech_Group |
Phanes are abstractions of highly complex organic molecules introduced for simplification of the naming of these highly complex molecules.
Systematic nomenclature of organic chemistry consists of building a name for the structure of an organic compound by a collection of names of its composite parts but describing als... | https://en.wikipedia.org/wiki/Phanes_(organic_chemistry) |
Phang Siew Moi is a full professor at the Department of Biotechnology, Faculty of Applied Science, UCSI University . [ 1 ] She is a leading expert in algal biotechnology and utilization, particularly converting algae into biodiesel . [ 2 ] [ 3 ] [ 4 ]
Dr. Phang Siew Moi, FASc is a distinguished professor and Deputy Vi... | https://en.wikipedia.org/wiki/Phang_Siew_Moi |
Phantom power , in the context of professional audio equipment , is DC electric power equally applied to both signal wires in balanced microphone cables, forming a phantom circuit , to operate microphones that contain active electronic circuitry. [ 1 ] It is best known as a convenient power source for condenser microph... | https://en.wikipedia.org/wiki/Phantom_power |
Pharmaceutical Research and Manufacturers of America ( PhRMA , pronounced /ˈfɑrmə/ ), formerly known as the Pharmaceutical Manufacturers Association, [ 1 ] is an American trade group representing companies in the pharmaceutical industry . Founded in 1958, PhRMA lobbies on behalf of pharmaceutical companies. [ 2 ] [ 3 ]... | https://en.wikipedia.org/wiki/Pharmaceutical_Research_and_Manufacturers_of_America |
Pharmaceutical bioinformatics is a research field related to bioinformatics but with the focus on studying biological and chemical processes in the pharmaceutical area; to understand how xenobiotics interact with the human body and the drug discovery process.
Whereas traditional bioinformatics is a wide subject it has... | https://en.wikipedia.org/wiki/Pharmaceutical_bioinformatics |
The distribution of medications has special drug safety and security considerations. [ 1 ] Some drugs require cold chain management in their distribution. [ 2 ]
The industry uses track and trace technology , though the timings for implementation and the information required vary across different countries, with varyin... | https://en.wikipedia.org/wiki/Pharmaceutical_distribution |
Pharmaceutical formulation , in pharmaceutics , is the process in which different chemical substances, including the active drug , are combined to produce a final medicinal product . The word formulation is often used in a way that includes dosage form .
Formulation studies involve developing a preparation of the drug... | https://en.wikipedia.org/wiki/Pharmaceutical_formulation |
The pharmaceutical industry is a medical industry that discovers, develops, produces, and markets pharmaceutical goods such as medications and medical devices . Medications are then administered to (or self-administered by) patients for curing or preventing disease or for alleviating symptoms of illness or injury. [ 1 ... | https://en.wikipedia.org/wiki/Pharmaceutical_industry |
Pharmaceutical microbiology is an applied branch of microbiology . It involves the study of microorganisms associated with the manufacture of pharmaceuticals e.g. minimizing the number of microorganisms in a process environment, excluding microorganisms and microbial byproducts like exotoxin and endotoxin from water a... | https://en.wikipedia.org/wiki/Pharmaceutical_microbiology |
Pharmaceutics is the discipline of pharmacy that deals with the process of turning a new chemical entity (NCE) or an existing drug into a medication to be used safely and effectively by patients. [ 1 ] The patients could be either humans or animals. Pharmaceutics helps relate the formulation of drugs to their delivery ... | https://en.wikipedia.org/wiki/Pharmaceutics |
Pharmacia was a pharmaceutical and biotechnological company in Sweden that merged with the American pharmaceutical company Upjohn in 1995.
Pharmacia company was founded in 1911 in Stockholm , Sweden by pharmacist Gustav Felix Grönfeldt at the Elgen Pharmacy. [ 1 ] [ 2 ] The company was named after the Greek word φαρμα... | https://en.wikipedia.org/wiki/Pharmacia |
Pharmacodynamics ( PD ) is the study of the biochemical and physiologic effects of drugs (especially pharmaceutical drugs ). The effects can include those manifested within animals (including humans), microorganisms , or combinations of organisms (for example, infection ).
Pharmacodynamics and pharmacokinetics are the... | https://en.wikipedia.org/wiki/Pharmacodynamics |
Pharmacoepidemiology is the study of the uses and effects of drugs in well-defined populations. [ 1 ] [ 2 ]
To accomplish this study, pharmacoepidemiology borrows from both pharmacology and epidemiology . Thus, pharmacoepidemiology is the bridge between both pharmacology and epidemiology. Pharmacology is the study of ... | https://en.wikipedia.org/wiki/Pharmacoepidemiology |
Pharmacogenomics , often abbreviated "PGx," is the study of the role of the genome in drug response. Its name ( pharmaco- + genomics ) reflects its combining of pharmacology and genomics . Pharmacogenomics analyzes how the genetic makeup of a patient affects their response to drugs. [ 1 ] It deals with the influence of... | https://en.wikipedia.org/wiki/Pharmacogenomics |
Drug discovery and development requires the integration of multiple scientific and technological disciplines. These include chemistry , biology , pharmacology , pharmaceutical technology and extensive use of information technology . The latter is increasingly recognised as Pharmacoinformatics . Pharmacoinformatics rela... | https://en.wikipedia.org/wiki/Pharmacoinformatics |
Pharmacokinetics (from Ancient Greek pharmakon "drug" and kinetikos "moving, putting in motion"; see chemical kinetics ), sometimes abbreviated as PK , is a branch of pharmacology dedicated to describing how the body affects a specific substance after administration. [ 1 ] The substances of interest include any chemic... | https://en.wikipedia.org/wiki/Pharmacokinetics |
Pharmacokinetics simulation is a simulation method used in determining the safety levels of a drug during its development .
Pharmacokinetics simulation gives an insight to drug efficacy and safety before exposure of individuals to the new drug that might help to improve the design of a clinical trial .
Pharmacokineti... | https://en.wikipedia.org/wiki/Pharmacokinetics_simulation |
Pharmacological cardiotoxicity is defined as cardiac damage that occurs under the action of a drug . This can occur both through damage of cardiac muscle as well as through alteration of the ion currents of cardiomyocytes . [ 1 ]
Two distinct drug classes in which cardiotoxicity can occur are in anti-cancer and antiar... | https://en.wikipedia.org/wiki/Pharmacological_cardiotoxicity |
Pharmacology is the science of drugs and medications, [ 1 ] including a substance's origin, composition, pharmacokinetics , pharmacodynamics , therapeutic use, and toxicology . More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal bioche... | https://en.wikipedia.org/wiki/Pharmacology |
The pharmacology of ethanol involves both pharmacodynamics (how it affects the body) and pharmacokinetics (how the body processes it). In the body, ethanol primarily affects the central nervous system, acting as a depressant and causing sedation, relaxation, and decreased anxiety. The complete list of mechanisms remain... | https://en.wikipedia.org/wiki/Pharmacology_of_ethanol |
Pharmacometabolomics , also known as pharmacometabonomics , is a field which stems from metabolomics , the quantification and analysis of metabolites produced by the body. [ 1 ] [ 2 ] It refers to the direct measurement of metabolites in an individual's bodily fluids, in order to predict or evaluate the metabolism of p... | https://en.wikipedia.org/wiki/Pharmacometabolomics |
In medicinal chemistry and molecular biology , a pharmacophore is an abstract description of molecular features that are necessary for molecular recognition of a ligand by a biological macromolecule . IUPAC defines a pharmacophore to be "an ensemble of steric and electronic features that is necessary to ensure the opti... | https://en.wikipedia.org/wiki/Pharmacophore |
Pharmacotoxicology entails the study of the consequences of toxic exposure to pharmaceutical drugs and agents in the health care field. The field of pharmacotoxicology also involves the treatment and prevention of pharmaceutically induced side effects . Pharmacotoxicology can be separated into two different categories... | https://en.wikipedia.org/wiki/Pharmacotoxicology |
Pharmacovigilance ( PV , or PhV ), also known as drug safety , is the pharmaceutical science relating to the "collection, detection, assessment, monitoring, and prevention" of adverse effects with pharmaceutical products . [ 1 ] : 7
The etymological roots for the word "pharmacovigilance" are: pharmakon (Greek for drug... | https://en.wikipedia.org/wiki/Pharmacovigilance |
The Pharmacovigilance Programme of India ( PvPI ) is an Indian government organization which identifies and responds to drug safety problems. [ 1 ] Its activities include receiving reports of adverse drug events and taking necessary action to remedy problems. [ 1 ] The Central Drugs Standard Control Organisation establ... | https://en.wikipedia.org/wiki/Pharmacovigilance_Programme_of_India |
Pharmacy is the science and practice of discovering, producing, preparing, dispensing, reviewing and monitoring medications , aiming to ensure the safe, effective, and affordable use of medicines . It is a miscellaneous science as it links health sciences with pharmaceutical sciences and natural sciences . The professi... | https://en.wikipedia.org/wiki/Pharmacy |
Pharmacy automation involves the mechanical processes of handling and distributing medications. Any pharmacy task may be involved, including counting small objects (e.g., tablets , capsules ); measuring and mixing powders and liquids for compounding ; tracking and updating customer information in databases (e.g., perso... | https://en.wikipedia.org/wiki/Pharmacy_automation |
Pharming , a portmanteau of farming and pharmaceutical , refers to the use of genetic engineering to insert genes that code for useful pharmaceuticals into host animals or plants that would otherwise not express those genes, thus creating a genetically modified organism (GMO). [ 1 ] [ 2 ] Pharming is also known as mole... | https://en.wikipedia.org/wiki/Pharming_(genetics) |
The pharyngeal artery is a branch of the ascending pharyngeal artery . The pharyngeal artery passes inferior-ward in between the superior margin of the superior pharyngeal constrictor muscle , and the levator veli palatini muscle . It issues branches to the constrictor muscles of the pharynx , the stylopharyngeus muscl... | https://en.wikipedia.org/wiki/Pharyngeal_artery |
Pharyngeal aspiration is the introduction of a substance into the pharynx and its subsequent aspiration into the lungs. It is used to test the respiratory toxicity of a substance in animal testing . It began to be used in the late 1990s. [ 1 ] Pharyngeal aspiration is widely used to study the toxicity of a wide varie... | https://en.wikipedia.org/wiki/Pharyngeal_aspiration |
The pharyngula is a stage in the embryonic development of vertebrates. [ 1 ] At this stage, the embryos of all vertebrates are similar, having developed features typical of vertebrates, such as the beginning of a spinal cord. Named by William Ballard , [ 2 ] the pharyngula stage follows the blastula , gastrula and neur... | https://en.wikipedia.org/wiki/Pharyngula |
In chemistry , a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of catalysis and can act through homogeneous catalysis or heterogeneous catalysis methods depending on the catal... | https://en.wikipedia.org/wiki/Phase-boundary_catalysis |
The phase-change incubator is a low-cost, low-maintenance incubator that tests for microorganisms in water supplies. It uses small balls containing a chemical compound that, when heated and then kept insulated, will stay at 37 °C (approx. 99 °F) for 24 hours. This allows cultures to be tested without the need for a lab... | https://en.wikipedia.org/wiki/Phase-change_incubator |
A phase-change material ( PCM ) is a substance which releases/absorbs sufficient energy at phase transition to provide useful heat or cooling. Generally the transition will be from one of the first two fundamental states of matter - solid and liquid - to the other. The phase transition may also be between non-classic... | https://en.wikipedia.org/wiki/Phase-change_material |
Phase-contrast imaging is a method of imaging that has a range of different applications. It measures differences in the refractive index of different materials to differentiate between structures under analysis. In conventional light microscopy , phase contrast can be employed to distinguish between structures of simi... | https://en.wikipedia.org/wiki/Phase-contrast_imaging |
Phase-contrast microscopy (PCM) is an optical microscopy technique that converts phase shifts in light passing through a transparent specimen to brightness changes in the image. Phase shifts themselves are invisible, but become visible when shown as brightness variations.
When light waves travel through a medium other... | https://en.wikipedia.org/wiki/Phase-contrast_microscopy |
A phase-field model is a mathematical model for solving interfacial problems. It has mainly been applied to solidification dynamics, [ 1 ] but it has also been applied to other situations such as viscous fingering , [ 2 ] fracture mechanics, [ 3 ] [ 4 ] [ 5 ] [ 6 ] hydrogen embrittlement , [ 7 ] and vesicle dynamics. [... | https://en.wikipedia.org/wiki/Phase-field_model |
Phase-field models on graphs are a discrete analogue to phase-field models , defined on a graph . They are used in image analysis (for feature identification) and for the segmentation of social networks .
For a graph with vertices V and edge weights ω i , j {\displaystyle \omega _{i,j}} , the graph Ginzburg–Landau fun... | https://en.wikipedia.org/wiki/Phase-field_models_on_graphs |
A phase-locked loop or phase lock loop ( PLL ) is a control system that generates an output signal whose phase is fixed relative to the phase of an input signal. Keeping the input and output phase in lockstep also implies keeping the input and output frequencies the same, thus a phase-locked loop can also track an inpu... | https://en.wikipedia.org/wiki/Phase-locked_loop |
The terms hold-in range , pull-in range (acquisition range), and lock-in range are widely used by engineers for the concepts of frequency deviation ranges within which phase-locked loop -based circuits can achieve lock under various additional conditions.
In the classic books on phase-locked loops , [ 1 ] [ 2 ] publis... | https://en.wikipedia.org/wiki/Phase-locked_loop_range |
In the late 20th and early 21st century, there has been a global movement towards the phase-out of polystyrene foam as a single use plastic (SUP). Early bans of polystyrene foam intended to eliminate ozone-depleting chlorofluorocarbons (CFCs), formerly a major component.
Expanded polystyrene, often termed Styrofoam , ... | https://en.wikipedia.org/wiki/Phase-out_of_polystyrene_foam |
Phase-space representation of quantum state vectors is a formulation of quantum mechanics elaborating the phase-space formulation with a Hilbert space. It "is obtained within the framework of the relative-state formulation. For this purpose, the Hilbert space of a quantum system is enlarged by introducing an auxiliary ... | https://en.wikipedia.org/wiki/Phase-space_wavefunctions |
In the physical sciences , a phase is a region of material that is chemically uniform, physically distinct, and (often) mechanically separable. In a system consisting of ice and water in a glass jar, the ice cubes are one phase, the water is a second phase, and the humid air is a third phase over the ice and water. The... | https://en.wikipedia.org/wiki/Phase_(matter) |
In physics and mathematics , the phase (symbol φ or ϕ) of a wave or other periodic function F {\displaystyle F} of some real variable t {\displaystyle t} (such as time) is an angle -like quantity representing the fraction of the cycle covered up to t {\displaystyle t} . It is expressed in such a scale that it varies b... | https://en.wikipedia.org/wiki/Phase_(waves) |
In the United States, an environmental site assessment is a report prepared for a real estate holding that identifies potential or existing environmental contamination liabilities . The analysis, often called an ESA , typically addresses both the underlying land as well as physical improvements to the property. A prop... | https://en.wikipedia.org/wiki/Phase_I_environmental_site_assessment |
Phase Transitions and Critical Phenomena is a 20-volume series of books, comprising review articles on phase transitions and critical phenomena , published during 1972-2001. It is "considered the most authoritative series on the topic". [ 1 ]
Volumes 1-6 were edited by Cyril Domb and Melville S. Green , and after Gree... | https://en.wikipedia.org/wiki/Phase_Transitions_and_Critical_Phenomena |
In observational astronomy , phase angle is the angle between the light incident onto an observed object and the light reflected from the object. In the context of astronomical observations, this is usually the angle Sun -object-observer.
For terrestrial observations, "Sun–object–Earth" is often nearly the same thing ... | https://en.wikipedia.org/wiki/Phase_angle_(astronomy) |
In thermal equilibrium , each phase (i.e. liquid , solid etc.) of physical matter comes to an end at a transitional point, or spatial interface , called a phase boundary , due to the immiscibility of the matter with the matter on the other side of the boundary. This immiscibility is due to at least one difference betw... | https://en.wikipedia.org/wiki/Phase_boundary |
A phase converter is a device that converts electric power provided as single phase to multiple phase or vice versa. The majority of phase converters are used to produce three-phase electric power from a single-phase source, thus allowing the operation of three-phase equipment at a site that only has single-phase elect... | https://en.wikipedia.org/wiki/Phase_converter |
A phase diagram in physical chemistry , engineering , mineralogy , and materials science is a type of chart used to show conditions (pressure, temperature, etc.) at which thermodynamically distinct phases (such as solid, liquid or gaseous states) occur and coexist at equilibrium .
Common components of a phase diagram... | https://en.wikipedia.org/wiki/Phase_diagram |
For any complex number written in polar form (such as r e i θ ), the phase factor is the complex exponential ( e iθ ), where the variable θ is the phase of a wave or other periodic function. The phase factor is a unit complex number , i.e. a complex number of absolute value 1 . It is commonly used in quantum mechanic... | https://en.wikipedia.org/wiki/Phase_factor |
Phase inversion or phase separation is a chemical phenomenon exploited in the fabrication of artificial membranes . It is performed by removing the solvent from a liquid-polymer solution, leaving a porous, solid membrane.
Phase inversion is a common method to form filtration membranes, which are typically formed using... | https://en.wikipedia.org/wiki/Phase_inversion_(chemistry) |
In quantum computing , phase kickback refers to the fact that controlled operations have effects on their controls, in addition to on their targets, and that these effects correspond to phasing operations. [ 1 ] [ 2 ] [ 3 ]
When a controlled operation, such as a Controlled NOT (CNOT) gate , is applied to two qubits, t... | https://en.wikipedia.org/wiki/Phase_kickback |
In mathematics , a phase portrait is a geometric representation of the orbits of a dynamical system in the phase plane . Each set of initial conditions is represented by a different point or curve .
Phase portraits are an invaluable tool in studying dynamical systems. They consist of a plot of typical trajectories in ... | https://en.wikipedia.org/wiki/Phase_portrait |
In physics, the phase problem is the problem of loss of information concerning the phase that can occur when making a physical measurement. The name comes from the field of X-ray crystallography , where the phase problem has to be solved for the determination of a structure from diffraction data. [ 1 ] The phase proble... | https://en.wikipedia.org/wiki/Phase_problem |
In quantum computing , and more specifically in superconducting quantum computing , the phase qubit is a superconducting device based on the superconductor–insulator–superconductor (SIS) Josephson junction , [ 1 ] designed to operate as a quantum bit , or qubit. [ 2 ]
The phase qubit is closely related, yet distinct f... | https://en.wikipedia.org/wiki/Phase_qubit |
Phase reduction is a method used to reduce a multi-dimensional dynamical equation describing a nonlinear limit cycle oscillator into a one-dimensional phase equation. [ 1 ] [ 2 ] Many phenomena in our world such as chemical reactions, electric circuits, mechanical vibrations, cardiac cells, and spiking neurons are exam... | https://en.wikipedia.org/wiki/Phase_reduction |
In signal processing , phase response is the relationship between the phase of a sinusoidal input and the output signal passing through any device that accepts input and produces an output signal, such as an amplifier or a filter . [ 1 ]
Amplifiers, filters, and other devices are often categorized by their amplitude a... | https://en.wikipedia.org/wiki/Phase_response |
A phase response curve ( PRC ) illustrates the transient change ( phase response ) in the cycle period of an oscillation induced by a perturbation as a function of the phase at which it is received. PRCs are used in various fields; examples of biological oscillations are the heartbeat, circadian rhythms , and the regu... | https://en.wikipedia.org/wiki/Phase_response_curve |
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