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Atomic diffusion Vacancy diffusion is a diffusion process whereby the random thermally-activated movement of atoms in a solid results in the net transport of atoms. For example, helium atoms inside a balloon can diffuse through the wall of the balloon and escape, resulting in the balloon slowly deflating. Other air mol... | https://en.wikipedia.org/wiki?curid=2684031 |
Atomic diffusion Since the prevalence of point vacancies increases in accordance with the Arrhenius equation, the rate of crystal solid state diffusion increases with temperature. For a single atom in a defect-free crystal, the movement can be described by the "random walk" model. In 3-dimensions it can be shown that a... | https://en.wikipedia.org/wiki?curid=2684031 |
Momentum diffusion most commonly refers to the diffusion, or spread of momentum between particles (atoms or molecules) of matter, often in the fluid state. This transport of momentum can occur in any direction of the fluid flow. can be attributed to either external pressure or shear stress or both. When pressure is app... | https://en.wikipedia.org/wiki?curid=2684087 |
Momentum diffusion The attraction between the layers of the fluid is the result of cohesive forces, and viscosity is the property that explains the nature and strength of cohesive forces within a fluid. It is common to experience the fact that the flowing fluid will exert a certain amount of force on the plate, trying ... | https://en.wikipedia.org/wiki?curid=2684087 |
Momentum diffusion The phrase "momentum diffusion" can also refer to the diffusion of the probability for a "single" particles to have a particular momentum. In this case, it is the probability distribution function that diffuses in momentum space, rather than the (conserved) quantity of momentum that diffuses among ma... | https://en.wikipedia.org/wiki?curid=2684087 |
Autofluorescence is the natural emission of light by biological structures such as mitochondria and lysosomes when they have absorbed light, and is used to distinguish the light originating from artificially added fluorescent markers (fluorophores). The most commonly observed autofluorescencing molecules are NADPH and ... | https://en.wikipedia.org/wiki?curid=2686488 |
Autofluorescence For example, cellular autofluorescence can be used as an indicator of cytotoxicity without the need to add fluorescent markers. The autofluorescence of human skin can be used to measure the level of advanced glycation end-products (AGEs), which are present in higher quantities during several human dise... | https://en.wikipedia.org/wiki?curid=2686488 |
The Chemical History of a Candle was the title of a series of six lectures on the chemistry and physics of flames given by Michael Faraday at the Royal Institution in 1848, as part of the series of Christmas lectures for young people founded by Faraday in 1825 and still given there every year. The lectures described th... | https://en.wikipedia.org/wiki?curid=2690730 |
The Chemical History of a Candle Faraday's ideas are still used as the basis for open teaching about energy in modern primary and secondary schools Lecture 1: A Candle: The Flame - Its Sources - Structure - Mobility - Brightness Lecture 2: Brightness of the Flame - Air necessary for Combustion - Production of Water Lec... | https://en.wikipedia.org/wiki?curid=2690730 |
Dielectric reluctance is a scalar measurement of a passive dielectric circuit (or element within that circuit) dependent on voltage and electric induction flux, and this is determined by deriving the ratio of their amplitudes. The units of dielectric reluctance are F (inverse farads—see daraf) [Ref. 1-3]. As seen above... | https://en.wikipedia.org/wiki?curid=2692315 |
Magnetic reluctance </math>, formula_1, formula_2 Magnetic reluctance, or magnetic resistance, is a concept used in the analysis of magnetic circuits. It is defined as the ratio of magnetomotive force (mmf) to magnetic flux. It represents the opposition to magnetic flux, and depends on the geometry and composition of a... | https://en.wikipedia.org/wiki?curid=2692841 |
Magnetic reluctance Reluctance is usually represented by a cursive capital formula_3. In both AC and DC fields, the reluctance is the ratio of the magnetomotive force (MMF) in a magnetic circuit to the magnetic flux in this circuit. In a pulsating DC or AC field, the reluctance also pulsates (see phasors). The definiti... | https://en.wikipedia.org/wiki?curid=2692841 |
János Irinyi (; sometimes also spelled "János Irínyi"; Romanian: Ioan Irinyi; 18 May 1817, in Albis [Romanian: Buduslau] – 17 December 1895, in Vértes (today Létavértes - Hungary) was a Hungarian chemist and inventor of the noiseless and non-explosive match. He achieved this by mixing the phosphorus with lead dioxide i... | https://en.wikipedia.org/wiki?curid=2694448 |
Fluid pipe Fluid pipes are a phenomenon driven by surface tension. When a pure water jet impinges on a reservoir, capillary waves are excited and propagate up the jet at the same speed that the jet falls. phenomenon may be observed with a kitchen faucet. When the diameter of the stream is 2–3 mm, placing an obstacle in... | https://en.wikipedia.org/wiki?curid=2695705 |
Copper chromite is an inorganic compound with the formula CuCrO. It is a black solid that is used to catalyze reactions in organic synthesis. The material was first described in 1908. The catalyst was developed in North America by Homer Burton Adkins and Wilbur Arthur Lazier, partly based on interrogation of German che... | https://en.wikipedia.org/wiki?curid=2698205 |
Copper chromite is produced by the exposure of copper barium ammonium chromate to temperatures of 350-450 °C, generally by a muffle furnace: Copper ammonium chromate is also used for production of copper chromite. It is generally utilized as an alternative to the route of barium ammonium chromate for usage in chemicals... | https://en.wikipedia.org/wiki?curid=2698205 |
Trihydrogen cation The trihydrogen cation or protonated molecular hydrogen is a cation (positive ion) with formula , consisting of three hydrogen nuclei (protons) sharing two electrons. The trihydrogen cation is one of the most abundant ions in the universe. It is stable in the interstellar medium (ISM) due to the low ... | https://en.wikipedia.org/wiki?curid=2699278 |
Trihydrogen cation " first suggested that may be present in interstellar space given the large amount of hydrogen in interstellar space and its reaction pathway was exothermic (~1.5 eV). This led to the suggestion of Watson and Herbst & Klemperer in 1973 that is responsible for the formation of many observed molecular ... | https://en.wikipedia.org/wiki?curid=2699278 |
Trihydrogen cation In theory, the cation has 10 isotopologues, resulting from the replacement of one or more protons by nuclei of the other hydrogen isotopes; namely, deuterium nuclei (deuterons, ) or tritium nuclei (tritons, ). Some of them have been detected in interstellar clouds. They differ in the atomic mass numb... | https://en.wikipedia.org/wiki?curid=2699278 |
Trihydrogen cation Its strong dipole and high abundance make it easily detectable by radioastronomy. can also react with atomic oxygen to form OH and H. OH then usually reacts with more H to create further hydrogenated molecules. At this point, the reaction between and H is no longer exothermic in interstellar clouds. ... | https://en.wikipedia.org/wiki?curid=2699278 |
Trihydrogen cation The transfer still yields a molecule and a H molecule, but can potentially change the total nuclear spin of the two molecules depending on the nuclear spins of the protons. When an ortho- and a para-H collide, the result may be a para- and an ortho-H. The spectroscopy of is challenging. The pure rota... | https://en.wikipedia.org/wiki?curid=2699278 |
Trihydrogen cation The detection of the first emission lines was reported in 1989 by Drossart "et al.", found in the ionosphere of Jupiter. Drossart found a total of 23 lines with a column density of 1.39/cm. Using these lines, they were able to assign a temperature to the of around , which is comparable to temperature... | https://en.wikipedia.org/wiki?curid=2699278 |
Trihydrogen cation As explained above, both diffuse and dense clouds have the same formation mechanism for , but different dominating destruction mechanisms. In dense clouds, proton transfer with CO is the dominating destruction mechanism. This corresponds to a predicted number density of 10 cm in dense clouds. In diff... | https://en.wikipedia.org/wiki?curid=2699278 |
Lanthanum oxide Lanthanum oxide, also known as lanthana, chemical formula LaO, is an inorganic compound containing the rare earth element lanthanum and oxygen. It is used in some ferroelectric materials, as a component of optical materials, and is a feedstock for certain catalysts, among other uses. is an odorless, whi... | https://en.wikipedia.org/wiki?curid=2700960 |
Lanthanum oxide In order of date discovered, the list of elements includes Cerium 58, Lanthanum 57, Erbium 68, Terbium 65, Yttrium 39, Ytterbium 70, Holmium 67, Thulium 69, Scandium 21, Praseodymium 59, Neodymium 60 and Dysprosium 66. Several of these new elements were either discovered or isolated by Carl Gustaf Mosan... | https://en.wikipedia.org/wiki?curid=2700960 |
Lanthanum oxide LaO is used to make optical glasses, to which this oxide confers increased density, refractive index, and hardness. Together with oxides of tungsten, tantalum, and thorium, LaO improves the resistance of the glass to attack by alkali. LaO is an ingredient for the manufacture of piezoelectric and thermoe... | https://en.wikipedia.org/wiki?curid=2700960 |
Thulium(III) oxide is a pale green solid compound, with the formula TmO. It was first isolated in 1879 from an impure sample of erbia by Per Teodor Cleve, who named it "thulia". It can be prepared in the laboratory by burning thulium metal in air, or by decomposition of their oxoacid salts, such as thulium nitrate. | https://en.wikipedia.org/wiki?curid=2701025 |
Tin oxide may refer to: | https://en.wikipedia.org/wiki?curid=2701899 |
Impervious surface Impervious surfaces are mainly artificial structures—such as pavements (roads, sidewalks, driveways and parking lots, as well as industrial areas such as airports, ports and logistics and distribution centres, all of which use considerable paved areas) that are covered by water-resistant materials su... | https://en.wikipedia.org/wiki?curid=2707059 |
Impervious surface coverage can be limited by restricting land use density (such as a number of homes per acre in a subdivision), but this approach causes land elsewhere (outside the subdivision) to be developed, to accommodate the growing population. (See "urban sprawl.") Alternatively, urban structures can be built d... | https://en.wikipedia.org/wiki?curid=2707059 |
Impervious surface It is calculated by measuring the percentage of a catchment area which is made up of impervious surfaces such as roads, roofs and other paved surfaces. An estimation of PIMP is given by PIMP = 6.4J^0.5 where J is the number of dwellings per hectare (Butler and Davies 2000). For example, woodland has ... | https://en.wikipedia.org/wiki?curid=2707059 |
Impervious surface The NLCD consistently quantifies the percent anthropogenic TIA for the NLCD at a 30-meter (a 900 m2) pixel resolution throughout the Nation. Within the data set, each pixel is quantified as having a TIA value that ranges from 0 to 100 percent. TIA estimates made with the NLCD impervious surface data ... | https://en.wikipedia.org/wiki?curid=2707059 |
Impervious surface Also, land use methods are selected to estimate potential effects of future development on TIA with planning maps that quantify projected changes in land use. There are substantial differences in actual and estimated TIA estimates from different studies in the literature. Terms like low density and h... | https://en.wikipedia.org/wiki?curid=2707059 |
Impervious surface 35 to 216 square miles and PDA values ranging from 0.16 to 99.06 percent. TIA also is estimated from population density data by estimating the population in an area of interest and using regression equations to calculate the associated TIA. Population-density data are used because nationally consiste... | https://en.wikipedia.org/wiki?curid=2707059 |
Impervious surface Natural impervious areas, depending on their nature and antecedent conditions, may produce stormflow from infiltration excess overland flow, saturation overland flow, or direct precipitation. The effects of natural impervious areas on runoff generation are expected to be more important in areas with ... | https://en.wikipedia.org/wiki?curid=2707059 |
Impervious surface For example, Felton and Lull (1963) measured infiltration rates for forest soils and lawns to indicate a potential 80 percent reduction in infiltration as a result of development activities. Similarly, Taylor (1982) did infiltrometer tests in areas before and after suburban development and noted that... | https://en.wikipedia.org/wiki?curid=2707059 |
Carbonyldiimidazole 1,1'-(CDI) is an organic compound with the molecular formula (CHN)CO. It is a white crystalline solid. It is often used for the coupling of amino acids for peptide synthesis and as a reagent in organic synthesis. CDI can be prepared straightforwardly by the reaction of phosgene with four equivalents... | https://en.wikipedia.org/wiki?curid=2709093 |
Carbonyldiimidazole In the realm of peptide synthesis, this product may be treated with an amine such as that found on an amino acid to release the imidazole group and couple the peptides. The side products, carbon dioxide and imidazole, are relatively innocuous. Racemization of the amino acids also tends to be minimal... | https://en.wikipedia.org/wiki?curid=2709093 |
Carbonyldiimidazole This reagent is a good formylating agent and can regenerate the unsubstituted imidazole (with formation of carbon monoxide) upon heating. Yet another reaction involves the acylation of triphenylalkelynephosphoranes. These can undergo the Wittig reaction to form α,β unsaturated ketones or aldehydes. ... | https://en.wikipedia.org/wiki?curid=2709093 |
Carbonyldiimidazole As CDI is an equivalent of phosgene, it can be used in similar reaction, however, with increased selectivity: it allows the synthesis of asymmetric bis alkyl carbonates | https://en.wikipedia.org/wiki?curid=2709093 |
Shock chlorination is a process used in many swimming pools, water wells, springs, and other water sources to reduce the bacterial and algal residue in the water. is performed by mixing a large amount of sodium hypochlorite, which can be in the form of a powder or a liquid such as chlorine bleach, into the water. The c... | https://en.wikipedia.org/wiki?curid=2710834 |
Shock chlorination It has been pointed out that ozone is an excellent alternative, a much more effective oxidizer than chlorine shock. | https://en.wikipedia.org/wiki?curid=2710834 |
Solar desalination is a technique to produce water with a low salt concentration from sea-water or brine using solar energy. There are two common methods of solar desalination. Either using the direct heat from the sun or using electricity generated by solar cells to power a membrane process. In the direct method, a so... | https://en.wikipedia.org/wiki?curid=2712280 |
Solar desalination They include but are not limited to multiple-effect humidification (MEH), multi-stage flash distillation (MSF), multiple-effect distillation (MED), multiple-effect boiling (MEB), humidification–dehumidification (HDH), reverse osmosis (RO), and freeze-effect distillation. Indirect solar desalination s... | https://en.wikipedia.org/wiki?curid=2712280 |
Solar desalination 7 m of distilled water a day using the effluent from mining operations as its feed water. of seawater and brackish groundwater in the modern United States extends back to the early 1950s when Congress passed the Conversion of Saline Water Act, which led to the establishment of the Office of Saline Wa... | https://en.wikipedia.org/wiki?curid=2712280 |
Solar desalination It is estimated that desalination plants powered by conventional fuels consume the equivalent of 203 million tons of fuel a year. With the approach (or passage) of peak oil production, fossil fuel prices will continue to increase as those resources decline; as a result solar energy will become a more... | https://en.wikipedia.org/wiki?curid=2712280 |
Solar desalination In Kuwait a MSF facility has been built using parabolic trough collectors to provide the necessary solar thermal energy to produce 100 m of fresh water a day. And in Northern China there is an experimental, automatic, unmanned operation that uses 80 m of vacuum tube solar collectors coupled with a 1 ... | https://en.wikipedia.org/wiki?curid=2712280 |
Solar desalination Secondly, the heat of condensation is valuable because it takes large amounts of solar energy to evaporate water and generate saturated, vapor-laden hot air. This energy is, by definition, transferred to the condenser's surface during condensation. With most forms of solar stills, this heat of conden... | https://en.wikipedia.org/wiki?curid=2712280 |
Solar desalination The driving force in this process is thermal solar energy to produce water vapor which is later condensed in a separate chamber. In sophisticated systems, waste heat is minimized by collecting the heat from the condensing water vapor and pre-heating the incoming water source. This system is effective... | https://en.wikipedia.org/wiki?curid=2712280 |
Solar desalination Furthermore, part of the consumed mechanical energy can be reclaimed from the concentrated brine effluent with an energy recovery device. Solar-powered RO desalination is common in demonstration plants due to the modularity and scalability of both photovoltaic (PV) and RO systems. A detailed economic... | https://en.wikipedia.org/wiki?curid=2712280 |
Zerewitinoff determination The or Zerevitinov determination is a quantitative chemical test for the determination of active hydrogens in a chemical substance. A sample is treated with the Grignard reagent, methylmagnesium iodide, which reacts with any acidic hydrogen atom to form methane. This gas can be determined qua... | https://en.wikipedia.org/wiki?curid=2715599 |
Zeisel determination The or Zeisel test is a chemical test for the presence of esters or ethers in a chemical substance. It is named after the Czech chemist Simon Zeisel (1854–1933). In a qualitative test a sample is first reacted with a mixture of acetic acid and hydrogen iodide in a test tube. The ensuing reaction re... | https://en.wikipedia.org/wiki?curid=2719234 |
Pidgeon process The is one of the methods of magnesium metal production, via a silicothermic reduction. Practical production requires roughly 35–40 MWh/ton of metal produced, which is on par with the molten salt electrolytic methods of production, though above the 7 MWh/ton theoretical minimum. The basic chemical equat... | https://en.wikipedia.org/wiki?curid=2719708 |
Pidgeon process Another way is using mined magnesite (MgCO) that has been calcined to magnesium oxide by carbon dioxide removal. By far the most used raw material is mined dolomite, a mixed (Ca,Mg)CO, where the calcium oxide present in the reaction zone scavenges the silica formed, releasing heat and consuming one of t... | https://en.wikipedia.org/wiki?curid=2719708 |
Pidgeon process There is still a feasible process with carbon, that uses shock-freezing of the vapors, to disallow any time for the reverse reaction - though such shock cooling is a far stretch from being an economical industrial process. At temperatures where the magnesium is still liquid or solid (say 600-700 °C), bu... | https://en.wikipedia.org/wiki?curid=2719708 |
Pidgeon process The process used externally heated retorts identical in concept to those used by Dr. Pidgeon two years later. Prior to the mid-1990s the world market for magnesium metal production was dominated by electrolytic processes, with the United States as the dominant supplier. For over 80 years Dow Chemical op... | https://en.wikipedia.org/wiki?curid=2719708 |
Pidgeon process In the past, besides the US, the other major magnesium producers have traditionally included Norsk Hydro of Norway/Canada, and to a lesser extent, the former Soviet Union countries, Brazil and France, all possessing cheap and abundant hydroelectric or nuclear electric power. A player recently stepping o... | https://en.wikipedia.org/wiki?curid=2719708 |
Nitrogen trifluoride is the inorganic compound with the formula NF. This nitrogen-fluorine compound is a colorless, nonflammable gas with a slightly musty odor. It finds increasing use as an etchant in microelectronics. is an extremely strong greenhouse gas. is a rare example of a binary fluoride that can be prepared d... | https://en.wikipedia.org/wiki?curid=2719832 |
Nitrogen trifluoride It oxidizes hydrogen chloride to chlorine: It converts to tetrafluorohydrazine upon contact with metals, but only at high temperatures: NF reacts with fluorine and antimony pentafluoride to give the tetrafluoroammonium salt: is used in the plasma etching of silicon wafers. Today nitrogen trifluorid... | https://en.wikipedia.org/wiki?curid=2719832 |
Nitrogen trifluoride It is compatible with steel and Monel, as well as several plastics. is a greenhouse gas, with a global warming potential (GWP) 17,200 times greater than that of when compared over a 100-year period. Its GWP place it second only to in the group of Kyoto-recognised greenhouse gases, and was included ... | https://en.wikipedia.org/wiki?curid=2719832 |
Nitrogen trifluoride Robson projected that the maximum atmospheric concentration is less than 0.16 parts per trillion (ppt) by volume, which will provide less than 0.001 Wm of IR forcing. The mean global tropospheric concentration of NF has risen from about 0.02 ppt (parts per trillion, dry air mole fraction) in 1980, ... | https://en.wikipedia.org/wiki?curid=2719832 |
Nitrogen trifluoride Following suit, the WBCSD/WRI GHG Protocol is amending all of its standards (corporate, product and Scope 3) to also cover NF. Skin contact with is not hazardous, and it is a relatively minor irritant to mucous membranes and eyes. It is a pulmonary irritant with a toxicity considerably lower than n... | https://en.wikipedia.org/wiki?curid=2719832 |
Silicothermic reaction Silicothermic reactions are thermic chemical reactions using silicon as the reducing agent at high temperature (800-1400°C). The most prominent example is the Pidgeon process for reducing magnesium metal from ores. Other processes include the Bolzano process and the magnetherm process. All three ... | https://en.wikipedia.org/wiki?curid=2721004 |
Aluminothermic reaction Aluminothermic reactions are exothermic chemical reactions using aluminium as the reducing agent at high temperature. The process is industrially useful for production of alloys of iron. The most prominent example is the thermite reaction between iron oxides and aluminium to produce iron itself:... | https://en.wikipedia.org/wiki?curid=2721041 |
Aluminothermic reaction The aluminothermic reaction is used for the production of several ferroalloys, for example ferroniobium from niobium pentoxide and ferrovanadium from iron, vanadium(V) oxide, and aluminium. The process begins with the reduction of the oxide by the aluminium: Other metals can be produced from the... | https://en.wikipedia.org/wiki?curid=2721041 |
Carbothermic reaction Carbothermic reactions involve the reduction of substances, often metal oxides (<chem>O^2-</chem>), using carbon as the reducing agent. These chemical reactions are usually conducted at temperatures of several hundred degrees Celsius. Such processes are applied for production of the elemental form... | https://en.wikipedia.org/wiki?curid=2721100 |
Carbothermic reaction A key step in this process is the reduction of sodium sulfate with coal: The NaS is then treated with calcium carbonate to give sodium carbonate, a commodity chemical. Recently, development of the 'MagSonic' carbothermic magnesium process has restarted interest in its chemistry: The reaction is re... | https://en.wikipedia.org/wiki?curid=2721100 |
Calciothermic reaction Calciothermic reactions are metallothermic reduction reactions (more generally, thermic chemical reactions) which use calcium metal as the reducing agent at high temperature. Calcium is one of the most potent reducing agents available, usually drawn as the strongest oxidic reductant in Ellingham ... | https://en.wikipedia.org/wiki?curid=2721326 |
Reformatsky reaction The (sometimes spelled Reformatskii reaction) is an organic reaction which condenses aldehydes or ketones with α-halo esters using metallic zinc to form β-hydroxy-esters: The organozinc reagent, also called a 'Reformatsky enolate', is prepared by treating an alpha-halo ester with zinc dust. Reforma... | https://en.wikipedia.org/wiki?curid=2721808 |
Reformatsky reaction In one variation of the an iodolactam is coupled with an aldehyde with triethylborane in toluene at -78 °C. | https://en.wikipedia.org/wiki?curid=2721808 |
Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH). It is a pale greenish blue or bluish green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist of a mixture of copper(II) carbonate and hydroxide. Cupric hydroxide is a ... | https://en.wikipedia.org/wiki?curid=2722147 |
Copper(II) hydroxide Thus copper slowly acquires a dull green coating in moist air by the reaction: The green material is in principle a 1:1 mole mixture of Cu(OH) and CuCO. This patina forms on bronze and other copper alloy statues such as the Statue of Liberty. The structure of Cu(OH) has been determined by X-ray cry... | https://en.wikipedia.org/wiki?curid=2722147 |
Copper(II) hydroxide This conversion is useful in the synthesis of carboxylic acids in the presence of other fragile functional groups. The yields are generally excellent as is the case with the production of benzoic acid and octanoic acid: in ammonia solution, known as Schweizer's reagent, possesses the interesting ab... | https://en.wikipedia.org/wiki?curid=2722147 |
Copper(II) hydroxide Azurite (2CuCO·Cu(OH)) and malachite (CuCO·Cu(OH)) are hydroxy-carbonates, whereas antlerite (CuSO·2Cu(OH)) and brochantite (CuSO·3Cu(OH)) are hydroxy-sulfates. Many synthetic copper(II) hydroxide derivatives have been investigated. | https://en.wikipedia.org/wiki?curid=2722147 |
Industrial fermentation is the intentional use of fermentation by microorganisms such as bacteria and fungi as well as eukaryotic cells like CHO cells and insect cells, to make products useful to humans. Fermented products have applications as food as well as in general industry. Some commodity chemicals, such as aceti... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation In most industrial fermentations, the organisms or eukaryotic cells are submerged in a liquid medium; in others, such as the fermentation of cocoa beans, coffee cherries, and miso, fermentation takes place on the moist surface of the medium. There are also industrial considerations related to th... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation Growth of the inoculum does not occur immediately. This is the period of adaptation, called the lag phase. Following the lag phase, the rate of growth of the organism steadily increases, for a certain period—this period is the log or exponential phase. After a phase of exponential growth, the ra... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation In the production of bio-ethanol, the medium may consist mostly of whatever inexpensive carbon source is available. Carbon sources are typically sugars or other carbohydrates, although in the case of substrate transformations (such as the production of vinegar) the carbon source may be an alcoho... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation The amount of phosphate which must be added depends upon the composition of the broth and the needs of the organism, as well as the objective of the fermentation. For instance, some cultures will not produce secondary metabolites in the presence of phosphate. Growth factors and trace nutrients a... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation This method involves changing only one factor at a time while keeping the other concentrations constant. This method can be separated into some sub groups. One is Removal Experiments. In this experiment all the components of the medium are removed one at a time and their effects on the medium ar... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation Primary metabolites are compounds made during the ordinary metabolism of the organism during the growth phase. A common example is ethanol or lactic acid, produced during glycolysis. Citric acid is produced by some strains of "Aspergillus niger" as part of the citric acid cycle to acidify their ... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation In the early days of the biotechnology industry, most biopharmaceutical products were made in "E. coli"; by 2004 more biopharmaceuticals were manufactured in eukaryotic cells, like CHO cells, than in microbes, but used similar bioreactor systems. Insect cell culture systems came into use in the ... | https://en.wikipedia.org/wiki?curid=2723752 |
Industrial fermentation They were developed long before man had any knowledge of the existence of the microorganisms involved. Some foods such as Marmite are the byproduct of the fermentation process, in this case in the production of beer. Fermentation is the main source of ethanol in the production of ethanol fuel. C... | https://en.wikipedia.org/wiki?curid=2723752 |
Van Slyke determination The is a chemical test for the determination of amino acids containing a primary amine group. It is named after the biochemist Donald Dexter Van Slyke (1883-1971). One of Van Slyke's first professional achievements was the quantification of amino acids by the reaction. To quantify aliphatic amin... | https://en.wikipedia.org/wiki?curid=2723787 |
Trapp mixture The is a specific mixture of organic solvents that allows chemical reactions to take place at very low temperatures. It is made up of THF:diethyl ether:pentane in a 4:4:1 ratio which remains liquid down to −110 °C and the same solvents in a 4:1:1 ratio remain a liquid down to −120 °C. This solvent system ... | https://en.wikipedia.org/wiki?curid=2723918 |
Swain equation The relates the kinetic isotope effect for the protium/tritium combination with that of the protium/deuterium combination according to: where k are the reaction rate constants for the protonated, deuterated and tritiated reactants respectively. | https://en.wikipedia.org/wiki?curid=2724263 |
Natural circulation refers to the ability of a fluid in a system to circulate continuously, with gravity and possible changes in heat energy. The difference of density being the only driving force. If the differences of density are caused by heat, this force is called as "thermal head" or "thermal driving head." A flui... | https://en.wikipedia.org/wiki?curid=2724356 |
Natural circulation It is achieved by reducing turbulence and friction in the fluid flow (that is, minimizing head loss), and by providing a way to remove any inoperative pumps from the fluid path. Also, the reactor (as the heat source) must be physically lower than the steam generators or turbines (the heat sink). In ... | https://en.wikipedia.org/wiki?curid=2724356 |
Uncleftish Beholding "Uncleftish Beholding" (1989) is a short text by Poul Anderson designed to illustrate what English might look like without its large number of loanwords from languages such as French, Greek, and Latin. Written in a form of "Anglish," the work explains atomic theory using Germanic words almost exclu... | https://en.wikipedia.org/wiki?curid=2726086 |
Uncleftish Beholding The text gained increased exposure and popularity after being circulated around the Internet, and has served as inspiration for some inventors of Germanic English conlangs. Douglas Hofstadter, in discussing the piece in his book "", jocularly refers to the use of only Germanic roots for scientific ... | https://en.wikipedia.org/wiki?curid=2726086 |
SNi Si or Substitution Nucleophilic internal stands for a specific but not often encountered nucleophilic aliphatic substitution reaction mechanism. The name was introduced by Cowdrey et al. in 1937 to label nucleophilic reactions which occur with retention of configuration, but later was employed to describe various r... | https://en.wikipedia.org/wiki?curid=2726466 |
SNi This reaction mechanism is supported by the observation that addition of pyridine to the reaction leads to inversion. The reasoning behind this finding is that pyridine reacts with the intermediate sulfite replacing chlorine. The dislodged chlorine has to resort to nucleophilic attack from the rear as in a regular ... | https://en.wikipedia.org/wiki?curid=2726466 |
Drug recall A drug recall removes a prescription or over-the-counter drug from the market. Drug recalls in the United States are made by the FDA or the creators of the drug when certain criteria are met. When a drug recall is made, the drug is removed from the market and potential legal action can be taken depending on... | https://en.wikipedia.org/wiki?curid=2727218 |
Drug recall " The syrup was sold until as late as 1930 in the United Kingdom. In 1971, Diethylstilbestrol (DES) was recalled from the market. It was intended to be used to prevent prenatal problems during pregnancy. Women who took DES were shown to have a greater chance of having breast cancer. It is estimated that 5 t... | https://en.wikipedia.org/wiki?curid=2727218 |
Drug recall This graph charts the rise in drug recalls by class in the United States from 2004 to 2014 with data from Regulatory Affairs Professionals Society The recall process in the United States follows three approximate phases. Distinct difficulties arise depending on the type of drug being recalled. Drug recalls ... | https://en.wikipedia.org/wiki?curid=2727218 |
Drug recall Level of recall refers to which part of the distribution chain to which the recall is extended (wholesale, retail, pharmacy, medical user, etc.). Notification is the way consumers are alerted to the recall. In cases of a severe health hazard, a press release must be promptly issued. The FDA recommends a wri... | https://en.wikipedia.org/wiki?curid=2727218 |
Drug recall Recalls are typically only advertised online and in the media, so consumers are subject to their own awareness. Lot numbers indicated on the packing allow only those affected to participate in recall. Prescription drug recalls are made simpler because they follow supply chain: the manufacturer notifies the ... | https://en.wikipedia.org/wiki?curid=2727218 |
Drug recall The Food and Drug Administration Modernization Act of 1997 was passed in order to streamline the FDA to meet standards of efficiency expected by the 21st century. In regards to drugs, the act lowered the regulatory obligations of pharmaceutical companies, allowing them to rely on one clinical trial for appr... | https://en.wikipedia.org/wiki?curid=2727218 |
Drug recall It would also allow reviews to be done by third parties instead of the FDA. Debates stem from the fact that approval could be based on anecdotal rather than scientific evidence. This act is debated due to the FDA’s seemingly close relations with medical device producers. The two industries collaborated to w... | https://en.wikipedia.org/wiki?curid=2727218 |
Hyperconjugation In organic chemistry, hyperconjugation (or σ-conjugation) refers to the delocalization of electrons with the participation of bonds of primarily σ-character. Usually, hyperconjugation involves the interaction of the electrons in a sigma (σ) orbital (e.g. C–H or C–C) with an adjacent unpopulated non-bon... | https://en.wikipedia.org/wiki?curid=2729378 |
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