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Physical organic chemistry , a term coined by Louis Hammett in 1940, refers to a discipline of organic chemistry that focuses on the relationship between chemical structures and reactivity , in particular, applying experimental tools of physical chemistry to the study of organic molecules . Specific focal points of stu... | https://en.wikipedia.org/wiki/Physical_organic_chemistry |
A phenomenon ( pl. : phenomena ), sometimes spelled phaenomenon , is an observable event . [ 1 ] The term came into its modern philosophical usage through Immanuel Kant , who contrasted it with the noumenon , which cannot be directly observed. Kant was heavily influenced by Gottfried Wilhelm Leibniz in this part of his... | https://en.wikipedia.org/wiki/Physical_phenomena |
A physical plant , building plant , mechanical plant or industrial plant (and where context is given, often just plant ) refers to the technical infrastructure used in operation and maintenance of a given facility. The operation of these technical facilities and services, or the department of an organization which does... | https://en.wikipedia.org/wiki/Physical_plant |
A physical property is any property of a physical system that is measurable . [ 1 ] The changes in the physical properties of a system can be used to describe its changes between momentary states. A quantifiable physical property is called physical quantity . Measurable physical quantities are often referred to as obse... | https://en.wikipedia.org/wiki/Physical_property |
A physical quantity (or simply quantity ) [ 1 ] [ a ] is a property of a material or system that can be quantified by measurement . A physical quantity can be expressed as a value , which is the algebraic multiplication of a numerical value and a unit of measurement . For example, the physical quantity mass , symbol m ... | https://en.wikipedia.org/wiki/Physical_quantity |
A physical system is a collection of physical objects under study. [ 1 ] The collection differs from a set : all the objects must coexist and have some physical relationship. [ 2 ] In other words, it is a portion of the physical universe chosen for analysis. Everything outside the system is known as the environment , w... | https://en.wikipedia.org/wiki/Physical_system |
Physical vapor deposition ( PVD ), sometimes called physical vapor transport ( PVT ), describes a variety of vacuum deposition methods which can be used to produce thin films and coatings on substrates including metals, ceramics, glass, and polymers. PVD is characterized by a process in which the material transitions f... | https://en.wikipedia.org/wiki/Physical_vapor_deposition |
Physics-informed neural networks ( PINNs ), [ 1 ] also referred to as Theory-Trained Neural Networks ( TTNs ), [ 2 ] are a type of universal function approximators that can embed the knowledge of any physical laws that govern a given data-set in the learning process, and can be described by partial differential equatio... | https://en.wikipedia.org/wiki/Physics-informed_neural_networks |
The Physics ( Greek : Φυσικὴ ἀκρόασις Phusike akroasis ; Latin : Physica , or Naturales Auscultationes , possibly meaning " Lectures on nature ") is a named text, written in ancient Greek, collated from a collection of surviving manuscripts known as the Corpus Aristotelicum , attributed to the 4th-century BC philosophe... | https://en.wikipedia.org/wiki/Physics_(Aristotle) |
Physics and Chemistry of Glasses: European Journal of Glass Science and Technology Part B is a bimonthly peer-reviewed scientific journal published by the Society of Glass Technology . It was established in 2006, from the merger of the Society of Glass Technology's journal Physics and Chemistry of Glasses [ 1 ] and the... | https://en.wikipedia.org/wiki/Physics_and_Chemistry_of_Glasses |
Physics beyond the Standard Model ( BSM ) refers to the theoretical developments needed to explain the deficiencies of the Standard Model , such as the inability to explain the fundamental parameters of the standard model, the strong CP problem , neutrino oscillations , matter–antimatter asymmetry , and the nature of d... | https://en.wikipedia.org/wiki/Physics_beyond_the_Standard_Model |
Physics of life is a branch of physics that studies the fundamental principles governing living systems. It applies methods from mechanics , thermodynamics , statistical physics , and information theory to biological phenomena ranging from molecular assemblies to ecosystems. [ 1 ] The field seeks to understand how comp... | https://en.wikipedia.org/wiki/Physics_of_Life |
Physics of failure is a technique under the practice of reliability design that leverages the knowledge and understanding of the processes and mechanisms that induce failure to predict reliability and improve product performance.
Other definitions of Physics of Failure include:
The concept of Physics of Failure, also... | https://en.wikipedia.org/wiki/Physics_of_failure |
Physics of financial markets is a non-orthodox economics discipline that studies financial markets as physical systems . It seeks to understand the nature of financial processes and phenomena by employing the scientific method and avoiding beliefs, unverifiable assumptions and immeasurable notions, not uncommon to econ... | https://en.wikipedia.org/wiki/Physics_of_financial_markets |
From the viewpoint of physics ( dynamics , to be exact), a firearm , as for most weapons , is a system for delivering maximum destructive energy to the target with minimum delivery of energy on the shooter. [ citation needed ] The momentum delivered to the target, however, cannot be any more than that (due to recoil) o... | https://en.wikipedia.org/wiki/Physics_of_firearms |
The physics of skiing refers to the analysis of the forces acting on a person while skiing .
The motion of a skier is determined by the physical principles of the conservation of energy and the frictional forces acting on the body. For example, in downhill skiing, as the skier is accelerated down the hill by the forc... | https://en.wikipedia.org/wiki/Physics_of_skiing |
Physiological agonism describes the action of a substance which ultimately produces the same effects in the body as another substance—as if they were both agonists at the same receptor —without actually binding to the same receptor. Physiological antagonism describes the behavior of a substance that produces effects co... | https://en.wikipedia.org/wiki/Physiological_agonism_and_antagonism |
Physiological condition [ 1 ] or, more often "physiological conditions" is a term used in biology , biochemistry , and medicine . It refers to conditions of the external or internal milieu that may occur in nature for that organism or cell system, in contrast to artificial laboratory conditions. A temperature range of ... | https://en.wikipedia.org/wiki/Physiological_condition |
In muscle physiology , physiological cross-sectional area (PCSA) is the area of the cross section of a muscle perpendicular to its fibers, generally at its largest point. It is typically used to describe the contraction properties of pennate muscles . [ 1 ] It is not the same as the anatomical cross-sectional area (ACS... | https://en.wikipedia.org/wiki/Physiological_cross-sectional_area |
Physiological functional capacity ( PFC ) is the ability to perform the physical tasks of daily life and the ease with which these tasks can be performed. PFC declines at some point with advancing age even in healthy adults, resulting in a reduced capacity to perform certain physical tasks. This can eventually result i... | https://en.wikipedia.org/wiki/Physiological_functional_capacity |
The term physiological prematurity (also described as altriciality ) refers to the fact that compared to most animals, humans are born in a premature biological state. Although sensory organs and skeletal and muscular systems are largely developed prenatally, human babies at the time of their birth are completely helpl... | https://en.wikipedia.org/wiki/Physiological_prematurity |
Physiological relevance is a scientific concept that refers to the applicability or significance of a particular experimental finding or biological observation in the context of normal bodily functions. This concept is often used in biomedical research , where scientists strive to design experiments that not only yield... | https://en.wikipedia.org/wiki/Physiological_relevance |
Physiologically based pharmacokinetic (PBPK) modeling is a mathematical modeling technique for predicting the absorption, distribution, metabolism and excretion (ADME) of synthetic or natural chemical substances in humans and other animal species. PBPK modeling is used in pharmaceutical research and drug development, a... | https://en.wikipedia.org/wiki/Physiologically_based_pharmacokinetic_modelling |
Physiology ( / ˌ f ɪ z i ˈ ɒ l ə dʒ i / ; from Ancient Greek φύσις ( phúsis ) ' nature, origin ' and -λογία ( -logía ) ' study of ' ) [ 1 ] is the scientific study of functions and mechanisms in a living system . [ 2 ] [ 3 ] As a subdiscipline of biology , physiology focuses on how organisms , organ systems , individua... | https://en.wikipedia.org/wiki/Physiology |
The physiology of marathons is typically associated with high demands on a marathon runner's cardiovascular system and their locomotor system . The marathon was conceived centuries ago and as of recent has been gaining popularity among many populations around the world. The 42.195 km (26.2 mile) distance is a physical ... | https://en.wikipedia.org/wiki/Physiology_of_marathons |
The physiome of an individual's or species ' physiological state is the description of its functional behavior. The physiome describes the physiological dynamics of the normal intact organism and is built upon information and
structure ( genome , proteome , and morphome ). The term comes from "physio-" (nature) and "-o... | https://en.wikipedia.org/wiki/Physiome |
The physiotope is the total abiotic matrix of habitat present within any certain ecotope . It refers to the landform, the rocks and the soils, the climate and the hydrology, and the geologic processes which marshalled all these resources together in a certain way and in this time and place [ 1 ]
Specifically, the phys... | https://en.wikipedia.org/wiki/Physiotope |
Physisorption , also called physical adsorption , is a process in which the electronic structure of the atom or molecule is barely perturbed upon adsorption . [ 1 ] [ 2 ] [ 3 ]
The fundamental interacting force of physisorption is Van der Waals force . Even though the interaction energy is very weak (~10–100 meV), phy... | https://en.wikipedia.org/wiki/Physisorption |
A phytase ( myo -inositol hexakisphosphate phosphohydrolase) is any type of phosphatase enzyme that catalyzes the hydrolysis of phytic acid (myo-inositol hexakisphosphate) – an indigestible, organic form of phosphorus that is found in many plant tissues, especially in grains and oil seeds – and releases a usable form o... | https://en.wikipedia.org/wiki/Phytase |
Phytobenthos ( / . f aɪ t oʊ ˈ b ɛ n θ ɒ s / ) (from Greek φυτόν ( phyton , meaning "plants") and βένθος ( benthos , meaning "depths") are autotrophic organisms found attached to bottom surfaces of aquatic environments, such as rocks, sediments, or even other organisms. [ 1 ] [ 2 ] [ 3 ] This photosynthetic community i... | https://en.wikipedia.org/wiki/Phytobenthos |
Phytochemistry is the study of phytochemicals , which are chemicals derived from plants . Phytochemists strive to describe the structures of the large number of secondary metabolites found in plants, the functions of these compounds in human and plant biology, and the biosynthesis of these compounds. Plants synthesize ... | https://en.wikipedia.org/wiki/Phytochemistry |
A phytochorion , in phytogeography , is a geographic area with a relatively uniform composition of plant species. Adjacent phytochoria do not usually have a sharp boundary, but rather a soft one, a transitional area in which many species from both regions overlap. The region of overlap is called a vegetation tension zo... | https://en.wikipedia.org/wiki/Phytochorion |
In oceanography , phytodetritus is the organic particulate matter resulting from phytoplankton and other organic material in surface waters falling to the seabed. This process takes place almost continuously as a " marine snow " of descending particles, falling at the rate of about 100 to 150 m (328 to 492 ft) per day.... | https://en.wikipedia.org/wiki/Phytodetritus |
Phytoecdysteroids are plant-derived ecdysteroids . Phytoecdysteroids are a class of chemicals that plants synthesize for defense against phytophagous (plant eating) insects. These compounds are mimics of hormones used by arthropods in the molting process known as ecdysis . It is presumed that these chemicals act as en... | https://en.wikipedia.org/wiki/Phytoecdysteroid |
A phytoestrogen is a plant-derived xenoestrogen (a type of estrogen produced by organisms other than humans) not generated within the endocrine system , but consumed by eating plants or manufactured foods. [ 1 ] Also called a "dietary estrogen", it is a diverse group of naturally occurring nonsteroidal plant compound... | https://en.wikipedia.org/wiki/Phytoestrogen |
Phytoextraction is a subprocess of phytoremediation in which plants remove dangerous elements or compounds from soil or water, most usually heavy metals , metals that have a high density and may be toxic to organisms even at relatively low concentrations. [ 1 ] The heavy metals that plants extract are toxic to the plan... | https://en.wikipedia.org/wiki/Phytoextraction_process |
Phytogeography (from Greek φυτόν, phytón = "plant" and γεωγραφία, geographía = "geography" meaning also distribution) or botanical geography is the branch of biogeography that is concerned with the geographic distribution of plant species and their influence on the earth's surface. [ 1 ] Phytogeography is concerned wit... | https://en.wikipedia.org/wiki/Phytogeography |
Phytogeomorphology is the study of how terrain features affect plant growth. [ 1 ] It was the subject of a treatise by Howard and Mitchell in 1985, who were considering the growth and varietal temporal and spatial variability found in forests, but recognized that their work also had application to farming , and the rel... | https://en.wikipedia.org/wiki/Phytogeomorphology |
The phytoglobin-nitric oxide cycle is a metabolic pathway induced in plants under hypoxic conditions which involves nitric oxide (NO) and phytoglobin (Pgb). [ 1 ] It provides an alternative type of respiration to mitochondrial electron transport under the conditions of limited oxygen supply. [ 2 ] Phytoglobin in hypoxi... | https://en.wikipedia.org/wiki/Phytoglobin-NO_cycle |
Phytoglycogen is a type of glycogen extracted from plants. It is a highly branched, water-soluble polysaccharide derived from glucose . [ 1 ]
Phytoglycogen is a highly branched polysaccharide used to store glucose in a similar way that glycogen is the glucose storage for animals. It is made up of branched, flexible ch... | https://en.wikipedia.org/wiki/Phytoglycogen |
Phytomining , sometimes called agromining , [ 1 ] is the concept of extracting heavy metals from the soil using plants. [ 2 ] Specifically, phytomining is for the purpose of economic gain. [ 3 ] The approach exploits the existence of hyperaccumulators , proteins or compounds secreted by plants to bind certain metal ion... | https://en.wikipedia.org/wiki/Phytomining |
A phytoplankton microbiome is the community of microorganisms—mainly bacteria, but also including fungi and viruses—that live in association with phytoplankton . These microbiomes play a critical role in marine ecosystems by supporting phytoplankton health, facilitating nutrient cycling, sustaining food webs, and contr... | https://en.wikipedia.org/wiki/Phytoplankton_microbiome |
Phytoremediation technologies use living plants to clean up soil, air and water contaminated with hazardous contaminants. [ 1 ] It is defined as "the use of green plants and the associated microorganisms, along with proper soil amendments and agronomic techniques to either contain, remove or render toxic environmental ... | https://en.wikipedia.org/wiki/Phytoremediation |
Phytosemiotics is a branch of biosemiotics that studies the sign processing capabilities present in plants. [ 1 ] Some functions that plants perform that utilize this simple semiosis includes cellular recognition, plant perception , intercellular communication , [ 1 ] and plant signal transduction . [ 2 ] Comparative t... | https://en.wikipedia.org/wiki/Phytosemiotics |
Phytosociology , also known as phytocoenology or simply plant sociology , is the study of groups of species of plant that are usually found together. Phytosociology aims to empirically describe the vegetative environment of a given territory. A specific community of plants is considered a social unit, the product of de... | https://en.wikipedia.org/wiki/Phytosociology |
Phytotechnology (from Ancient Greek φυτο ( phyto ) ' plant ' and τεχνολογία (technología) ; from τέχνη (téchnē) ' art, skill, craft ' and -λογία ( -logía ) ' study of- ' ) implements solutions to scientific and engineering problems in the form of plants . It is distinct from ecotechnology and biotechnology as these fie... | https://en.wikipedia.org/wiki/Phytotechnology |
Phytotelma (plural phytotelmata ) is a small water-filled cavity in a terrestrial plant. The water accumulated within these plants may serve as the habitat for associated fauna and flora .
A rich literature in German summarised by Thienemann (1954) [ 1 ] developed many aspects of phytotelm biology. Reviews of the subj... | https://en.wikipedia.org/wiki/Phytotelma |
Phytotope refers to the total habitat available for colonization by plants within a specific biotope, such as a forest, meadow, wetland, or urban green space. The term is primarily used in ecology to describe the portion of an environment that can support plant life, taking into account factors such as soil type, clima... | https://en.wikipedia.org/wiki/Phytotope |
Phytotoxicity describes any adverse effects on plant growth, physiology , or metabolism caused by a chemical substance , such as high levels of fertilizers, herbicides, heavy metals, or nanoparticles . [ 1 ] General phytotoxic effects include altered plant metabolism, growth inhibition, or plant death. [ 2 ] Changes to... | https://en.wikipedia.org/wiki/Phytotoxicity |
A phytotron is an enclosed research greenhouse used for studying interactions between plants and the environment. It was a product of the disciplines of plant physiology and botany .
Phytotrons unified and extended earlier piecemeal efforts to claim total control of the whole environment. In both walk-in rooms and sma... | https://en.wikipedia.org/wiki/Phytotron |
In chemistry, π-effects or π-interactions are a type of non-covalent interaction that involves π systems . Just like in an electrostatic interaction where a region of negative charge interacts with a positive charge, the electron-rich π system can interact with a metal (cationic or neutral), an anion, another molecule ... | https://en.wikipedia.org/wiki/Pi-interaction |
In chemistry , pi stacking (also called π–π stacking ) refers to the presumptively attractive, noncovalent pi interactions between the pi bonds of aromatic rings, because of orbital overlap. [ 1 ] According to some authors direct stacking of aromatic rings (the "sandwich interaction") is electrostatically repulsive.
W... | https://en.wikipedia.org/wiki/Pi-stacking |
Pi (stylized as π ) [ a ] is a 1998 American conceptual psychological thriller film written and directed by Darren Aronofsky (in his feature directorial debut ). Pi was filmed on high-contrast black-and-white reversal film . The title refers to the mathematical constant pi . [ 5 ] [ 6 ] The story focuses on a mathemati... | https://en.wikipedia.org/wiki/Pi_(film) |
Pi Day is an annual celebration of the mathematical constant π (pi) . Pi Day is observed on March 14 (the 3rd month) since 3, 1, and 4 are the first three significant figures of π , and was first celebrated in the United States. [ 2 ] [ 3 ] It was founded in 1988 by Larry Shaw , an employee of a science museum in San F... | https://en.wikipedia.org/wiki/Pi_Day |
Pi Epsilon Tau ( ΠΕΤ ) is an American honor society for petroleum engineering students. Its purpose is to maintain the standards and high ideals of the petroleum engineering profession and to build a bond between its members and the industry. The society was established in 1947 at the University of Oklahoma .
Faculty ... | https://en.wikipedia.org/wiki/Pi_Epsilon_Tau |
A Josephson junction (JJ) is a quantum mechanical device which is made of two superconducting electrodes separated by a barrier (thin insulating tunnel barrier, normal metal, semiconductor, ferromagnet, etc.).
A π Josephson junction is a Josephson junction in which the Josephson phase φ equals π in the ground state, i... | https://en.wikipedia.org/wiki/Pi_Josephson_junction |
Pi Notebook is the trade name of a notebook produced by Japanese stationery manufacturer KING JIM and sold by Loft , which began selling the product in June 2017.
The notebook is characterized by its ruled lines, a series of pi (3.1415926535...) [ 1 ] Originally, the product was forfeited. Still, when it was posted on... | https://en.wikipedia.org/wiki/Pi_Notebook |
In chemistry , pi backbonding or π backbonding is a π-bonding interaction between a filled (or half filled) orbital of a transition metal atom and a vacant orbital on an adjacent ion or molecule. [ 1 ] [ 2 ] In this type of interaction, electrons from the metal are used to bond to the ligand , which dissipates excess n... | https://en.wikipedia.org/wiki/Pi_backbonding |
In chemistry , pi bonds ( π bonds ) are covalent chemical bonds , in each of which two lobes of an orbital on one atom overlap with two lobes of an orbital on another atom, and in which this overlap occurs laterally. Each of these atomic orbitals has an electron density of zero at a shared nodal plane that passes throu... | https://en.wikipedia.org/wiki/Pi_bond |
The pEDA parameter ( pi electron donor-acceptor ) is a pi-electron substituent effect scale, described also as mesomeric or resonance effect . There is also a complementary scale - sEDA . The more positive is the value of pEDA the more pi-electron donating is a substituent. The more negative pEDA, the more pi-electron ... | https://en.wikipedia.org/wiki/Pi_electron_donor-acceptor |
Pi in the Sky was an experimental aerial art display where airplanes spelled out pi to decimal 1,000 places in the sky over the San Francisco Bay Area . The display took place on September 12, 2012. It was then displayed again in Austin on March 13, 2014, during the SXSW festival, at which time it was said to be the l... | https://en.wikipedia.org/wiki/Pi_in_the_Sky |
Pi is 3 is a misunderstanding that the Japanese public believed that, due to the revision of the Japanese Curriculum guideline in 2002, the approximate value of pi (π), which had previously been taught as 3.14, is now taught as 3 in arithmetic education. [ 1 ] [ 2 ] [ 3 ] [ 4 ] In fact, this is not true, and even after... | https://en.wikipedia.org/wiki/Pi_is_3 |
In 1976, the Italian chemist, Giovanni Piancatelli and coworkers developed a new method to synthesize 4-hydroxycyclopentenone derivatives from 2-furylcarbinols through an acid-catalyzed rearrangement. [ 1 ] [ 2 ] This discovery occurred when Piancatelli was studying heterocyclic steroids and their reactive abilities in... | https://en.wikipedia.org/wiki/Piancatelli_rearrangement |
PicSat was a French observatory nanosatellite , designed to measure the transit of Beta Pictoris b , an exoplanet which orbits the star Beta Pictoris .
PicSat was designed and built by a team of scientists led by Dr. Sylvestre Lacour, astrophysicist and instrumentalist at the High Angular Resolution in Astrophysics gr... | https://en.wikipedia.org/wiki/PicSat |
In mathematics , specifically the study of differential equations , the Picard–Lindelöf theorem gives a set of conditions under which an initial value problem has a unique solution. It is also known as Picard's existence theorem , the Cauchy–Lipschitz theorem , or the existence and uniqueness theorem .
The theorem is ... | https://en.wikipedia.org/wiki/Picard–Lindelöf_theorem |
The Pickands–Balkema–De Haan theorem gives the asymptotic tail distribution of a random variable when its true distribution is unknown. It is often called the second theorem in extreme value theory . Unlike the first theorem (the Fisher–Tippett–Gnedenko theorem ), which concerns the maximum of a sample, the Pickands–Ba... | https://en.wikipedia.org/wiki/Pickands–Balkema–De_Haan_theorem |
A Pickering emulsion , sometimes named Ramsden emulsion , is an emulsion that is stabilized by solid particles (for example colloidal silica ) which adsorb onto the interface between the water and oil phases . Typically, the emulsions are either water-in-oil or oil-in-water emulsions, but other more complex systems suc... | https://en.wikipedia.org/wiki/Pickering_emulsion |
Picoline- N -oxide describes any of three isomers with the formula CH 3 C 5 H 4 NO . All are colorless solids. Their properties and those of pyridine- N -oxide ( C 5 H 5 NO ) are similar. | https://en.wikipedia.org/wiki/Picoline-N-oxide |
In the field of ordinary differential equations , the Picone identity , named after Mauro Picone , [ 1 ] is a classical result about homogeneous linear second order differential equations. Since its inception in 1910 it has been used with tremendous success in association with an almost immediate proof of the Sturm com... | https://en.wikipedia.org/wiki/Picone_identity |
The term picotechnology is a portmanteau of picometre and technology , intended to parallel the term nanotechnology . It is a hypothetical future level of technological manipulation of matter, on the scale of trillionths of a metre or picoscale (10 −12 ). This is three orders of magnitude smaller than a nanometre (and ... | https://en.wikipedia.org/wiki/Picotechnology |
Picramic acid , also known as 2-amino-4,6-dinitrophenol , [ 3 ] is an acid obtained by neutralizing an alcoholic solution of picric acid with ammonium hydroxide . Hydrogen sulfide is then added to the resulting solution, which turns red, yielding sulfur and red crystals. These are the ammonium salts of picramic acid, f... | https://en.wikipedia.org/wiki/Picramic_acid |
Picric acid is an organic compound with the formula (O 2 N) 3 C 6 H 2 OH. Its IUPAC name is 2,4,6-trinitrophenol ( TNP ). The name "picric" comes from Greek : πικρός ( pikros ), meaning "bitter", due to its bitter taste. It is one of the most acidic phenols . Like other strongly nitrated organic compounds, picric acid ... | https://en.wikipedia.org/wiki/Picric_acid |
Picryl chloride is an organic compound with the formula ClC 6 H 2 (NO 2 ) 3 . It is a bright yellow solid that is highly explosive, as is typical for polynitro aromatics such as picric acid . Its detonation velocity is 7,200 m/s.
The reactivity of picryl chloride is strongly influenced by the presence of three electr... | https://en.wikipedia.org/wiki/Picryl_chloride |
Pictet's experiment is the demonstration of the reflection of heat and the apparent reflection of cold in a series of experiments [ 1 ] performed in 1790 (reported in English in 1791 in An Essay on Fire [ 2 ] ) by Marc-Auguste Pictet —ten years before the discovery of infrared heating of the Earth by the Sun. [ 3 ] The... | https://en.wikipedia.org/wiki/Pictet's_experiment |
6-Phenanthridine
3,4-Benzoquinoline
9-Azaphenanthrene
3,4-Benzoisioquinoline
5-Azaphenanthrene
Phenanthridine is a nitrogen heterocyclic compound with the formula C 13 H 9 N . It is a colorless solid, although impure samples can be brownish. It is a precursor to DNA-binding fluorescent dyes through intercalation . Ex... | https://en.wikipedia.org/wiki/Pictet–Hubert_reaction |
The Pictet–Spengler reaction is a chemical reaction in which a β-arylethylamine undergoes condensation with an aldehyde or ketone followed by ring closure. The reaction was first discovered in 1911 by Amé Pictet and Theodor Spengler (22 February 1886 – 18 August 1965). [ 1 ] Traditionally, an acidic catalyst in protic ... | https://en.wikipedia.org/wiki/Pictet–Spengler_reaction |
In painting , photography , graphical perspective and descriptive geometry , a picture plane is an image plane located between the "eye point" (or oculus ) and the object being viewed and is usually coextensive to the material surface of the work. It is ordinarily a vertical plane perpendicular to the sightline to the ... | https://en.wikipedia.org/wiki/Picture_plane |
In mathematics, the Pidduck polynomials s n ( x ) are polynomials introduced by Pidduck ( 1910 , 1912 ) given by the generating function
( Roman 1984 , 4.4.3), ( Boas & Buck 1958 , p.38)
This polynomial -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Pidduck_polynomials |
The Pidgeon process is a practical method for smelting magnesium . The most common method involves the raw material, dolomite being fed into an externally heated reduction tank and then thermally reduced to metallic magnesium using 75% ferrosilicon as a reducing agent in a vacuum . [ 1 ] Overall the processes in magnes... | https://en.wikipedia.org/wiki/Pidgeon_process |
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The pie rule , sometimes referred to as the swap rule , is a rule used to balance abstract strategy games where a first-move advantage has been demonstrated. After the first move is made in a game that uses the pie rule, the second player must select one of tw... | https://en.wikipedia.org/wiki/Pie_rule |
In mathematics, a piecewise algebraic space is a generalization of a semialgebraic set , introduced by Maxim Kontsevich and Yan Soibelman . The motivation was for the proof of Deligne's conjecture on Hochschild cohomology . Robert Hardt, Pascal Lambrechts, Victor Turchin, and Ismar Volić later developed the theory.
Th... | https://en.wikipedia.org/wiki/Piecewise_algebraic_space |
In mathematics , piecewise syndeticity is a notion of largeness of subsets of the natural numbers .
A set S ⊂ N {\displaystyle S\subset \mathbb {N} } is called piecewise syndetic if there exists a finite subset G of N {\displaystyle \mathbb {N} } such that for every finite subset F of N {\displaystyle \mathbb {N} } th... | https://en.wikipedia.org/wiki/Piecewise_syndetic_set |
A pier , in architecture , is an upright support for a structure or superstructure such as an arch or bridge . Sections of structural walls between openings (bays) can function as piers. External or free-standing walls may have piers at the ends or on corners.
The simplest cross section of the pier is square , or rect... | https://en.wikipedia.org/wiki/Pier_(architecture) |
The Pierce Protein Assay is a method of protein quantification . It provides quick estimation of the protein amount in a given sample. [ 1 ]
The assay is separated into three main parts:
preparation of the Diluted Albumin (BSA) Standards,
preparation of the bicinchoninic acid (BCA) working reagent,
and quantification ... | https://en.wikipedia.org/wiki/Pierce_Protein_Assay |
In mathematics, Pieri's formula , named after Mario Pieri , describes the product of a Schubert cycle by a special Schubert cycle in the Schubert calculus , or the product of a Schur polynomial by a complete symmetric function.
In terms of Schur functions s λ indexed by partitions λ, it states that
where h r is a com... | https://en.wikipedia.org/wiki/Pieri's_formula |
Pierre A. Deymier is a researcher in phononics , [ 1 ] acoustic metamaterial , [ 1 ] and materials science . He is a Professor of Materials Science and Engineering and previously department head at the University of Arizona . [ 2 ] He holds appointments with the applied mathematics graduate interdisciplinary program, [... | https://en.wikipedia.org/wiki/Pierre_Deymier |
Pierre Gabriel (1 August 1933 [ 1 ] – 24 November 2015), also known as Peter Gabriel , was a French mathematician at the University of Strasbourg (1962–1970), University of Bonn (1970–1974) and University of Zürich (1974–1998) who worked on category theory , algebraic groups , and representation theory of algebras. He... | https://en.wikipedia.org/wiki/Pierre_Gabriel |
Pierre Monsan (born June 25, 1948, in Prades, Pyrénées-Orientales , France ) [ 1 ] is a French biochemist and entrepreneur. He is currently Professor emeritus at the Institut national des sciences appliquées de Toulouse (INSA Toulouse, affiliated to the University of Toulouse ) and the founding director of the pre-indu... | https://en.wikipedia.org/wiki/Pierre_Monsan |
Pierre Samuel (12 September 1921 [ 1 ] – 23 August 2009 [ 2 ] ) was a French mathematician , known for his work in commutative algebra and its applications to algebraic geometry . The two-volume work Commutative Algebra that he wrote with Oscar Zariski is a classic. Other books of his covered projective geometry and al... | https://en.wikipedia.org/wiki/Pierre_Samuel |
Pierre Scerri is a French telecommunications engineer and model builder, who gained fame in 1998 after having his highly accurate 1:3 scale model of a Ferrari 312 PB featured on the BBC television programme Jeremy Clarkson's Extreme Machines .
He began his project for the model in 1978, out of desire for having a Ferr... | https://en.wikipedia.org/wiki/Pierre_Scerri |
Pierre de Fermat ( / f ɜːr ˈ m ɑː / ; [ 2 ] French: [pjɛʁ də fɛʁma] ; 17 August 1601 [ a ] – 12 January 1665) was a French mathematician who is given credit for early developments that led to infinitesimal calculus , including his technique of adequality . In particular, he is recognized for his discovery of an origina... | https://en.wikipedia.org/wiki/Pierre_de_Fermat |
Piet Bergveld ( Dutch pronunciation: [pid ˈbɛr(ə)xfɛlt] ; born 26 January 1940) is a Dutch electrical engineer. He was professor of biosensors at the University of Twente between 1983 and 2003. He is the inventor of the ion-sensitive field-effect transistor (ISFET) sensor . [ 1 ] Bergveld's work has focused on electric... | https://en.wikipedia.org/wiki/Piet_Bergveld |
Pieter Baas (28 April 1944 – 29 April 2024) was a Dutch botanist and an emeritus professor of plant systematics at the Leiden University .
He served as director of the Rijksherbarium [ nl ] of Leiden University between 1991 and 1999. When the institute was faced with budget cuts in 1993 he managed to preserve the coll... | https://en.wikipedia.org/wiki/Pieter_Baas |
Pieter Hendrik Schoute (21 January 1846, Wormerveer – 18 April 1913, Groningen ) was a Dutch mathematician known for his work on regular polytopes and Euclidean geometry .
He started his career as a civil engineer, but became a professor of mathematics at Groningen and published some thirty papers on polytopes between... | https://en.wikipedia.org/wiki/Pieter_Hendrik_Schoute |
Piezochromism , from the Greek piezô "to squeeze, to press" and chromos "color", [ 1 ] describes the tendency of certain materials to change color with the application of pressure . This effect is closely related to the electronic band gap change, which can be found in plastics , semiconductors (e.g. hybrid perovskites... | https://en.wikipedia.org/wiki/Piezochromism |
A piezoelectric microelectromechanical system (piezoMEMS) is a miniature or microscopic device that uses piezoelectricity to generate motion and carry out its tasks. It is a microelectromechanical system that takes advantage of an electrical potential that appears under mechanical stress . PiezoMEMS can be found in a v... | https://en.wikipedia.org/wiki/Piezoelectric_microelectromechanical_systems |
Piezoelectricity ( / ˌ p iː z oʊ -, ˌ p iː t s oʊ -, p aɪ ˌ iː z oʊ -/ , US : / p i ˌ eɪ z oʊ -, p i ˌ eɪ t s oʊ -/ [ 1 ] ) is the electric charge that accumulates in certain solid materials—such as crystals , certain ceramics , and biological matter such as bone , DNA , and various proteins —in response to applied mec... | https://en.wikipedia.org/wiki/Piezoelectricity |
The piezoelectrochemical transducer effect (PECT) is a coupling between the electrochemical potential and the mechanical strain in ion-insertion-based electrode materials. It is similar to the piezoelectric effect – with both exhibiting a voltage-strain coupling - although the PECT effect relies on movement of ions wit... | https://en.wikipedia.org/wiki/Piezoelectrochemical_transducer_effect |
Piezoluminescence is a form of luminescence created by pressure upon certain solids. This phenomenon is characterized by recombination processes involving electrons, holes and impurity ion centres. [ 1 ] Some piezoelectric crystals give off a certain amount of piezoluminescence when under pressure. Irradiated salts, s... | https://en.wikipedia.org/wiki/Piezoluminescence |
Piezomagnetism is a phenomenon observed in some antiferromagnetic and ferrimagnetic crystals. It is characterized by a linear coupling between the system's magnetic polarization and mechanical strain . In a piezomagnetic material, one may induce a spontaneous magnetic moment by applying mechanical stress , or a physica... | https://en.wikipedia.org/wiki/Piezomagnetism |
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