|
PO2(OH) in mathematics
{{Letter-NumberCombDisambig ...
Po2, pO2, , or PO2 may refer to: * A military rank: ** Petty Officer 2nd Class in the Canadian military ** Petty Officer Second Class in the United States military * Polikarpov Po-2 or U-2, a Soviet aeroplane * Partial pressure of Oxygen, that is, amount of oxygen in the blood (normally referred to as Dissolved Oxygen) * : Phosphorus dioxide, a gaseous free radical that plays a role in the chemiluminescence of phosphorus and phosphine. * : Polonide anion * a power of two A power of two is a number of the form where is an integer, that is, the result of exponentiation with number 2, two as the Base (exponentiation), base and integer as the exponent. In the fast-growing hierarchy, is exactly equal to f_1^ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petty Officer 2nd Class
Petty officer second class (PO2) is a rank found in some navies and maritime organizations. Canada Petty officer, 2nd class, (PO 2), is a Naval non-commissioned member rank of the Canadian Forces. It is senior to the rank of master sailor (formerly master seaman) and its equivalents, and junior to petty officer 1st-class and its equivalents. Its Army and Air Force equivalent is sergeant (Sgt); together, Sgts and PO 2s make up the cadre of senior non-commissioned officers. The rank insignia of the PO 2 is three gold chevrons, point down, surmounted by a gold maple leaf. A PO 2 is generally initially addressed as “Petty Officer ” or "PO ", and thereafter as "PO", although in correspondence the full rank or abbreviation is used before the member's name. The full appellation Petty Officer 2nd Class or PO 2 in speech is generally used only when the second-class distinction must be made, such as to distinguish between members with similar names but differing ranks, or on promot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petty Officer Second Class
Petty officer second class (PO2) is a rank found in some navies and maritime organizations. Canada Petty officer, 2nd class, (PO 2), is a Naval non-commissioned member rank of the Canadian Forces. It is senior to the rank of master sailor (formerly master seaman) and its equivalents, and junior to petty officer 1st-class and its equivalents. Its Army and Air Force equivalent is sergeant (Sgt); together, Sgts and PO 2s make up the cadre of senior non-commissioned officers. The rank insignia of the PO 2 is three gold chevrons, point down, surmounted by a gold maple leaf. A PO 2 is generally initially addressed as “Petty Officer ” or "PO ", and thereafter as "PO", although in correspondence the full rank or abbreviation is used before the member's name. The full appellation Petty Officer 2nd Class or PO 2 in speech is generally used only when the second-class distinction must be made, such as to distinguish between members with similar names but differing ranks, or on prom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polikarpov Po-2
The Polikarpov Po-2 (also U-2 before 1944, for its initial Glossary of Russian and USSR aviation acronyms: Aircraft designations, ''uchebnyy'', 'training', role as a flight instruction aircraft) was an all-weather multirole Soviet Union, Soviet biplane, nicknamed ''Kukuruznik'' (,Gunston 1995, p. 292. NATO reporting name "Mule"). The reliable, uncomplicated design of the Po-2 made it an ideal trainer aircraft, as well as doubling as a low-cost attack aircraft, ground attack, aerial reconnaissance, psychological warfare and liaison aircraft during war, proving to be one of the most versatile light combat types to be built in the Soviet Union.Angelucci and Matricardi 1978, p. 214. As of 1978, it remained in production for a longer period of time than any other Soviet-era aircraft. It holds the distinction of the only biplane to take down a jet aircraft. Production figures for Polikarpov U-2 and Po-2 bombers and trainers combined are between 20,000 and 30,000 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Partial Pressure
In a mixture of gases, each constituent gas has a partial pressure which is the notional pressure of that constituent gas as if it alone occupied the entire volume of the original mixture at the same temperature. The total pressure of an ideal gas mixture is the sum of the partial pressures of the gases in the mixture (Dalton's Law). In respiratory physiology, the partial pressure of a dissolved gas in liquid (such as oxygen in arterial blood) is also defined as the partial pressure of that gas as it would be undissolved in gas phase yet in equilibrium with the liquid. This concept is also known as blood gas tension. In this sense, the diffusion of a gas liquid is said to be driven by differences in partial pressure (not concentration). In chemistry and thermodynamics, this concept is generalized to non-ideal gases and instead called fugacity. The partial pressure of a gas is a measure of its Thermodynamic activity, thermodynamic activity. Gases dissolve, diffuse, and react accor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissolved Oxygen
Oxygen saturation (symbol SO2) is a relative measure of the concentration of oxygen that is dissolved or carried in a given medium as a proportion of the maximal concentration that can be dissolved in that medium at the given temperature. It can be measured with a dissolved oxygen probe such as an oxygen sensor or an optode in liquid media, usually water. The standard unit of oxygen saturation is percent (%). Oxygen saturation can be measured regionally and noninvasively. Arterial oxygen saturation (SaO2) is commonly measured using pulse oximetry. Tissue saturation at peripheral scale can be measured using NIRS. This technique can be applied on both muscle and brain. In medicine In medicine, oxygen saturation refers to ''oxygenation'', or when oxygen molecules () enter the tissues of the body. In this case blood is oxygenated in the lungs, where oxygen molecules travel from the air into the blood. Oxygen saturation (() sats) measures the percentage of hemoglobin bindin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Dioxide
Phosphorus dioxide () is a gaseous oxide of phosphorus. It is a free radical that plays a role in the chemiluminescence of phosphorus and phosphine. It is produced when phosphates are heated to high temperatures. In the ground state the molecule is bent, like nitrogen dioxide Nitrogen dioxide is a chemical compound with the formula . One of several nitrogen oxides, nitrogen dioxide is a reddish-brown gas. It is a paramagnetic, bent molecule with C2v point group symmetry. Industrially, is an intermediate in the s ..., but there is an excited state that is linear. References {{inorganic-compound-stub Phosphorus oxides Free radicals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Free Radical
A daughter category of ''Ageing'', this category deals only with the biological aspects of ageing. Ageing Biogerontology Biological processes Causes of death Cellular processes Gerontology Life extension Metabolic disorders Metabolism Old age Time in life {{CatAutoTOC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemiluminescence
Chemiluminescence (also chemoluminescence) is the emission of light (luminescence) as the result of a chemical reaction, i.e. a chemical reaction results in a flash or glow of light. A standard example of chemiluminescence in the laboratory setting is the luminol test. Here, blood is indicated by luminescence upon contact with iron in hemoglobin. When chemiluminescence takes place in living organisms, the phenomenon is called bioluminescence. A light stick emits light by chemiluminescence. Physical description As in many chemical reactions, chemiluminescence starts with the combining of two compounds, say A and B, to give a product C. Unlike most chemical reactions, the product C converts to a further product, which is produced in an electronically excited state often indicated with an asterisk: : A + B → C : C → D* D* then emits a photon (''h''ν), to give the ground state of D: I : D* → D + ''h''ν In theory, one photon of light should be given off for each mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus
Phosphorus is a chemical element; it has Chemical symbol, symbol P and atomic number 15. All elemental forms of phosphorus are highly Reactivity (chemistry), reactive and are therefore never found in nature. They can nevertheless be prepared artificially, the two most common allotropes being white phosphorus and red phosphorus. With as its only stable isotope, phosphorus has an occurrence in Earth's crust of about 0.1%, generally as phosphate rock. A member of the pnictogen family, phosphorus readily forms a wide variety of organic compound, organic and inorganic compound, inorganic compounds, with as its main oxidation states +5, +3 and −3. The isolation of white phosphorus in 1669 by Hennig Brand marked the scientific community's first discovery since Antiquity of an element. The name phosphorus is a reference to the Phosphorus (morning star), god of the Morning star in Greek mythology, inspired by the faint glow of white phosphorus when exposed to oxygen. This property is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphine
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting fish, due to the presence of substituted phosphine and diphosphane (). With traces of present, is spontaneously flammable in air ( pyrophoric), burning with a luminous flame. Phosphine is a highly toxic respiratory poison, and is immediately dangerous to life or health at 50 ppm. Phosphine has a trigonal pyramidal structure. Phosphines are compounds that include and the organophosphines, which are derived from by substituting one or more hydrogen atoms with organic groups. They have the general formula . Phosphanes are saturated phosphorus hydrides of the form , such as triphosphane. Phosphine () is the smallest of the phosphines and the smallest of the phosphanes. History Philippe Gengembre (1764–1838), a student of Lavoisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polonide
A polonide is a chemical compound of the radioactive element polonium with any element less electronegative than polonium. Polonides are usually prepared by a direct reaction between the elements at temperatures of around 300–400 °C... They are amongst the most chemically stable compounds of polonium,. and can be divided into two broad groups: *ionic polonides, which appear to contain the Po2− anion; *intermetallic polonides, in which the bonding is more complex. Some polonides are intermediate between these two cases and others are non-stoichiometric compounds. Alloys containing polonium are also classed as polonides. As polonium is immediately below tellurium in the periodic table, there are many chemical and structural similarities between polonides and tellurides. Naturally occurring polonides Lead polonide (PbPo) occurs naturally, as lead is produced in the alpha decay of polonium. Ionic polonides The polonides of the most electropositive metals show classic ionic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
