AcetyleneNitrogenase: An enzyme system that catalyzes the fixing of nitrogen in soil bacteria and blue-green algae (CYANOBACTERIA). EC 1.18.6.1.EthaneNitrogen Fixation: The process in certain BACTERIA; FUNGI; and CYANOBACTERIA converting free atmospheric NITROGEN to biologically usable forms of nitrogen, such as AMMONIA; NITRATES; and amino compounds.Alkynes: Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.Tungsten: Tungsten. A metallic element with the atomic symbol W, atomic number 74, and atomic weight 183.85. It is used in many manufacturing applications, including increasing the hardness, toughness, and tensile strength of steel; manufacture of filaments for incandescent light bulbs; and in contact points for automotive and electrical apparatus.Azotobacter: A genus of gram-negative, aerobic bacteria found in soil and water. Its organisms occur singly, in pairs or irregular clumps, and sometimes in chains of varying lengths.Nitrosomonas: A genus of gram-negative, ellipsoidal or rod-shaped bacteria whose major source of energy and reducing power is from the oxidation of ammonia to nitrite. Its species occur in soils, oceans, lakes, rivers, and sewage disposal systems.Hydrocarbons, Acyclic: Organic compounds composed exclusively of carbon and hydrogen where no carbon atoms join to form a ring structure.Ethylenes: Derivatives of ethylene, a simple organic gas of biological origin with many industrial and biological use.Molybdoferredoxin: A non-heme iron-sulfur protein isolated from Clostridium pasteurianum and other bacteria. It is a component of NITROGENASE, which is active in nitrogen fixation, and consists of two subunits with molecular weights of 59.5 kDa and 50.7 kDa, respectively.Nitrous Oxide: Nitrogen oxide (N2O). A colorless, odorless gas that is used as an anesthetic and analgesic. High concentrations cause a narcotic effect and may replace oxygen, causing death by asphyxia. It is also used as a food aerosol in the preparation of whipping cream.Hydrogen: The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.Deltaproteobacteria: A group of PROTEOBACTERIA represented by morphologically diverse, anaerobic sulfidogens. Some members of this group are considered bacterial predators, having bacteriolytic properties.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Azotobacter vinelandii: A species of gram-negative, aerobic bacteria first isolated from soil in Vineland, New Jersey. Ammonium and nitrate are used as nitrogen sources by this bacterium. It is distinguished from other members of its genus by the ability to use rhamnose as a carbon source. (From Bergey's Manual of Determinative Bacteriology, 9th ed)Methane: The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)Molybdenum: A metallic element with the atomic symbol Mo, atomic number 42, and atomic weight 95.94. It is an essential trace element, being a component of the enzymes xanthine oxidase, aldehyde oxidase, and nitrate reductase. (From Dorland, 27th ed)Spirillum: A genus of gram-negative, curved and spiral-shaped bacteria found in stagnant, freshwater environments. These organisms are motile by bipolar tufts of flagella having a long wavelength and about one helical turn. Some species of Spirillum cause a form of RAT-BITE FEVER.PropaneAmmonia: A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.Nitrogen: An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Biofuels: Hydrocarbon-rich byproducts from the non-fossilized BIOMASS that are combusted to generate energy as opposed to fossilized hydrocarbon deposits (FOSSIL FUELS).Investments: Use for articles on the investing of funds for income or profit.Coal: A natural fuel formed by partial decomposition of vegetable matter under certain environmental conditions.Fossil Fuels: Any combustible hydrocarbon deposit formed from the remains of prehistoric organisms. Examples are petroleum, coal, and natural gas.FiresIncineration: High temperature destruction of waste by burning with subsequent reduction to ashes or conversion to an inert mass.Wood: A product of hard secondary xylem composed of CELLULOSE, hemicellulose, and LIGNANS, that is under the bark of trees and shrubs. It is used in construction and as a source of CHARCOAL and many other products.Heating: The application of heat to raise the temperature of the environment, ambient or local, or the systems for accomplishing this effect. It is distinguished from HEAT, the physical property and principle of physics.Fresh Water: Water containing no significant amounts of salts, such as water from RIVERS and LAKES.Nitrification: A process facilitated by specialized bacteria involving the oxidation of ammonium to nitrite and nitrate.Ventriculography, First-Pass: Radionuclide ventriculography where a bolus of radionuclide is injected and data are recorded from one pass through the heart ventricle. Left and right ventricular function can be analyzed independently during this technique. First-pass ventriculography is preferred over GATED BLOOD-POOL IMAGING for assessing right ventricular function.Denitrification: Nitrate reduction process generally mediated by anaerobic bacteria by which nitrogen available to plants is converted to a gaseous form and lost from the soil or water column. It is a part of the nitrogen cycle.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.PubMed: A bibliographic database that includes MEDLINE as its primary subset. It is produced by the National Center for Biotechnology Information (NCBI), part of the NATIONAL LIBRARY OF MEDICINE. PubMed, which is searchable through NLM's Web site, also includes access to additional citations to selected life sciences journals not in MEDLINE, and links to other resources such as the full-text of articles at participating publishers' Web sites, NCBI's molecular biology databases, and PubMed Central.Steam: Water in its gaseous state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Silicon Dioxide: Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.Polyethylene Glycols: Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Silicosis: A form of pneumoconiosis resulting from inhalation of dust containing crystalline form of SILICON DIOXIDE, usually in the form of quartz. Amorphous silica is relatively nontoxic.Chemistry, Pharmaceutical: Chemistry dealing with the composition and preparation of agents having PHARMACOLOGIC ACTIONS or diagnostic use.Cold Temperature: An absence of warmth or heat or a temperature notably below an accustomed norm.Cyperus: A plant genus of the family CYPERACEAE. SESQUITERPENES are found in some of the species.Chemical Hazard Release: Uncontrolled release of a chemical from its containment that either threatens to, or does, cause exposure to a chemical hazard. Such an incident may occur accidentally or deliberately.Yellow Fever: An acute infectious disease primarily of the tropics, caused by a virus and transmitted to man by mosquitoes of the genera Aedes and Haemagogus. The severe form is characterized by fever, HEMOLYTIC JAUNDICE, and renal damage.Polyesters: Polymers of organic acids and alcohols, with ester linkages--usually polyethylene terephthalate; can be cured into hard plastic, films or tapes, or fibers which can be woven into fabrics, meshes or velours.Hazardous Substances: Elements, compounds, mixtures, or solutions that are considered severely harmful to human health and the environment. They include substances that are toxic, corrosive, flammable, or explosive.Oxygenases: Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.Cytochrome P-450 Enzyme System: A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.Mixed Function Oxygenases: Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.7-Alkoxycoumarin O-Dealkylase: A drug-metabolizing enzyme found in the hepatic, placental and intestinal microsomes that metabolizes 7-alkoxycoumarin to 7-hydroxycoumarin. The enzyme is cytochrome P-450- dependent.
Comparative phylogeny of rrs and nifH genes in the Bacillaceae. (1/323)
The rrs (16S rDNA) gene sequences of nitrogen-fixing endospore-forming bacilli isolated from the rhizosphere of wheat and maize were determined in order to infer their phylogenetic position in the Bacillaceae. These rhizosphere strains form a monophyletic cluster with Paenibacillus azotofixans, Paenibacillus polymyxa and Paenibacillus macerans. Two of them (RSA19 and TOD45) had previously been identified as Bacillus circulans (group 2) by phenotypic characterization (API 50CH). Evidence for nitrogen fixation by P. azotofixans, P. polymyxa, P. macerans and putative B. circulans strains RSA19 and TOD45 was provided by acetylene-reduction activity, and confirmed by amplifying and sequencing a nifH fragment (370 nt). The phylogenetic tree of nifH-derived amino acid sequences was compared to the phylogenetic tree of rrs sequences. All Paenibacillus nifH sequences formed a coherent cluster distinct from that of related nitrogen-fixing anaerobic clostridia and Gram-positive high-G+C-content frankiae. The nifH gene was neither detected in the B. circulans type strain (ATCC 4513T) nor in the type strains of Bacillus subtilis, Bacillus cereus, Bacillus alcalophilus, Bacillus simplex, Brevibacillus brevis and Paenibacillus validus. Accordingly, nitrogen fixation among aerobic endospore-forming Firmicutes seems to be restricted to a subset of species in the genus Paenibacillus. (+info)Evidence for involvement of gut-associated denitrifying bacteria in emission of nitrous oxide (N(2)O) by earthworms obtained from garden and forest soils. (2/323)
Earthworms (Aporrectodea caliginosa, Lumbricus rubellus, and Octolasion lacteum) obtained from nitrous oxide (N(2)O)-emitting garden soils emitted 0.14 to 0.87 nmol of N(2)O h(-1) g (fresh weight)(-1) under in vivo conditions. L. rubellus obtained from N(2)O-emitting forest soil also emitted N(2)O, which confirmed previous observations (G. R. Karsten and H. L. Drake, Appl. Environ. Microbiol. 63:1878-1882, 1997). In contrast, commercially obtained Lumbricus terrestris did not emit N(2)O; however, such worms emitted N(2)O when they were fed (i.e., preincubated in) garden soils. A. caliginosa, L. rubellus, and O. lacteum substantially increased the rates of N(2)O emission of garden soil columns and microcosms. Extrapolation of the data to in situ conditions indicated that N(2)O emission by earthworms accounted for approximately 33% of the N(2)O emitted by garden soils. In vivo emission of N(2)O by earthworms obtained from both garden and forest soils was greatly stimulated when worms were moistened with sterile solutions of nitrate or nitrite; in contrast, ammonium did not stimulate in vivo emission of N(2)O. In the presence of nitrate, acetylene increased the N(2)O emission rates of earthworms; in contrast, in the presence of nitrite, acetylene had little or no effect on emission of N(2)O. In vivo emission of N(2)O decreased by 80% when earthworms were preincubated in soil supplemented with streptomycin and tetracycline. On a fresh weight basis, the rates of N(2)O emission of dissected earthworm gut sections were substantially higher than the rates of N(2)O emission of dissected worms lacking gut sections, indicating that N(2)O production occurred in the gut rather than on the worm surface. In contrast to living earthworms and gut sections that produced N(2)O under oxic conditions (i.e., in the presence of air), fresh casts (feces) from N(2)O-emitting earthworms produced N(2)O only under anoxic conditions. Collectively, these results indicate that gut-associated denitrifying bacteria are responsible for the in vivo emission of N(2)O by earthworms and contribute to the N(2)O that is emitted from certain terrestrial ecosystems. (+info)Diversity in butane monooxygenases among butane-grown bacteria. (3/323)
Butane monooxygenases of butane-grown Pseudomonas butanovora, Mycobacterium vaccae JOB5, and an environmental isolate, CF8, were compared at the physiological level. The presence of butane monooxygenases in these bacteria was indicated by the following results. (i) O(2) was required for butane degradation. (ii) 1-Butanol was produced during butane degradation. (iii) Acetylene inhibited both butane oxidation and 1-butanol production. The responses to the known monooxygenase inactivator, ethylene, and inhibitor, allyl thiourea (ATU), discriminated butane degradation among the three bacteria. Ethylene irreversibly inactivated butane oxidation by P. butanovora but not by M. vaccae or CF8. In contrast, butane oxidation by only CF8 was strongly inhibited by ATU. In all three strains of butane-grown bacteria, specific polypeptides were labeled in the presence of [(14)C]acetylene. The [(14)C]acetylene labeling patterns were different among the three bacteria. Exposure of lactate-grown CF8 and P. butanovora and glucose-grown M. vaccae to butane induced butane oxidation activity as well as the specific acetylene-binding polypeptides. Ammonia was oxidized by all three bacteria. P. butanovora oxidized ammonia to hydroxylamine, while CF8 and M. vaccae produced nitrite. All three bacteria oxidized ethylene to ethylene oxide. Methane oxidation was not detected by any of the bacteria. The results indicate the presence of three distinct butane monooxygenases in butane-grown P. butanovora, M. vaccae, and CF8. (+info)Measurement of cardiac output during exercise by open-circuit acetylene uptake. (4/323)
Noninvasive measurement of cardiac output (QT) is problematic during heavy exercise. We report a new approach that avoids unpleasant rebreathing and resultant changes in alveolar PO(2) or PCO(2) by measuring short-term acetylene (C(2)H(2)) uptake by an open-circuit technique, with application of mass balance for the calculation of QT. The method assumes that alveolar and arterial C(2)H(2) pressures are the same, and we account for C(2)H(2) recirculation by extrapolating end-tidal C(2)H(2) back to breath 1 of the maneuver. We correct for incomplete gas mixing by using He in the inspired mixture. The maneuver involves switching the subject to air containing trace amounts of C(2)H(2) and He; ventilation and pressures of He, C(2)H(2), and CO(2) are measured continuously (the latter by mass spectrometer) for 20-25 breaths. Data from three subjects for whom multiple Fick O(2) measurements of QT were available showed that measurement of QT by the Fick method and by the C(2)H(2) technique was statistically similar from rest to 90% of maximal O(2) consumption (VO(2 max)). Data from 12 active women and 12 elite male athletes at rest and 90% of VO(2 max) fell on a single linear relationship, with O(2) consumption (VO(2)) predicting QT values of 9.13, 15.9, 22.6, and 29.4 l/min at VO(2) of 1, 2, 3, and 4 l/min. Mixed venous PO(2) predicted from C(2)H(2)-determined QT, measured VO(2), and arterial O(2) concentration was approximately 20-25 Torr at 90% of VO(2 max) during air breathing and 10-15 Torr during 13% O(2) breathing. This modification of previous gas uptake methods, to avoid rebreathing, produces reasonable data from rest to heavy exercise in normal subjects. (+info)Attributes of atmospheric carbon monoxide oxidation by Maine forest soils. (5/323)
CO, one of the most important trace gases, regulates tropospheric methane, hydroxyl radical, and ozone contents. Ten to 25% of the estimated global CO flux may be consumed by soils annually. Depth profiles for (14)CO oxidation and CO concentration indicated that CO oxidation occurred primarily in surface soils and that photooxidation of soil organic matter did not necessarily contribute significantly to CO fluxes. Kinetic analyses revealed that the apparent K(m) was about 18 nM (17 ppm) and the V(max) was 6.9 micromol g (fresh weight)(-1) h(-1); the apparent K(m) was similar to the apparent K(m) for atmospheric methane consumption, but the V(max) was more than 100 times higher. Atmospheric CO oxidation responded sensitively to soil water regimes; decreases in water content in initially saturated soils resulted in increased uptake, and optimum uptake occurred at water contents of 30 to 60%. However, extended drying led to decreased uptake and net CO production. Rewetting could restore CO uptake, albeit with a pronounced hysteresis. The responses to changing temperatures indicated that the optimum temperature for net uptake was between 20 and 25 degrees C and that there was a transition to net production at temperatures above 30 degrees C. The responses to methyl fluoride and acetylene indicated that populations other than ammonia oxidizers and methanotrophs must be involved in forest soils. The response to acetylene was notable, since the strong initial inhibition was reversed after 12 h of incubation; in contrast, methyl fluoride did not have an inhibitory effect. Ammonium did not inhibit CO uptake; the level of nitrite inhibition was initially substantial, but nitrite inhibition was reversible over time. Nitrite inhibition appeared to occur through indirect effects based on abiological formation of NO. (+info)Noninvasive cardiac output measurement in orthostasis: pulse contour analysis compared with acetylene rebreathing. (6/323)
We tested the reliability of noninvasive cardiac output (CO) measurement in different body positions by pulse contour analysis (CO(pc)) by using a transmission line model (K. H. Wesseling, B. De Wit, J. A. P. Weber, and N. T. Smith. Adv. Cardiol. Phys. 5, Suppl. II: 16-52, 1983). Acetylene rebreathing (CO(rebr)) was used as a reference method. Twelve subjects (age 21-34 yr) were studied: 1) six in whom CO(rebr) and CO(pc) were measured in the standing and 6 degrees head-down tilt (HDT) postures and 2) six in whom CO was measured in the 30 degrees HDT, supine, 30 degrees head up-tilt (HUT), and 70 degrees HUT postures on a tilt table. The CO(rebr)-to-CO(pc) ratio in (near) the supine position during rebreathing was used as the calibration factor for CO(pc) measurements. Calibrated CO(pc) (CO(cal sup)) consistently overestimated CO in the upright posture. The drop in CO with upright posture was underestimated by approximately 50%. CO(cal sup) and CO(rebr) values did not differ in the 30 degrees HDT position. Changes in the CO(rebr)-to-CO(pc) ratio are highly variable among subjects in response to a change in posture. Therefore, CO(pc) must be recalibrated for each subject in each posture. (+info)Two forms of nitrogenase from the photosynthetic bacterium Rhodospirillum rubrum. (7/323)
Acetylene reduction by nitrogenase from Rhodospirillum rubrum, unlike that by other nitrogenases, was recently found by other investigators to require an activation of the iron protein of nitrogenase by an activating system comprising a chromatophore membrane component, adenosine 5'-triphosphate (ATP), and divalent metal ions. In an extension of this work, we observed that the same activating system was also required for nitrogenase-linked H(2) evolution. However, we found that, depending on their nitrogen nutrition regime, R. rubrum cells produced two forms of nitrogenase that differed in their Fe protein components. Cells whose nitrogen supply was totally exhausted before harvest yielded predominantly a form of nitrogenase (A) whose enzymatic activity was not governed by the activating system, whereas cells supplied up to harvest time with N(2) or glutamate yielded predominantly a form of nitrogenase (R) whose enzymatic activity was regulated by the activating system. An unexpected finding was the rapid (less than 10 min in some cases) intracellular conversion of nitrogenase A to nitrogenase R brought about by the addition to nitrogen-starved cells of glutamine, asparagine, or, particularly, ammonia. This finding suggests that mechanisms other than de novo protein synthesis were involved in the conversion of nitrogenase A to the R form. The molecular weights of the Fe protein and Mo-Fe protein components from nitrogenases A and R were the same. However, nitrogenase A appeared to be larger in size, because it had more Fe protein units per Mo-Fe protein than did nitrogenase R. A distinguishing property of the Fe protein from nitrogenase R was its ATP requirement. When combined with the Mo-Fe protein (from either nitrogenase A or nitrogenase R), the R form of Fe protein required a lower ATP concentration but bound or utilized more ATP molecules during acetylene reduction than did the A form of Fe protein. No differences between the Fe proteins from the two forms of nitrogenase were found in the electron paramagnetic resonance spectrum, midpoint oxidation-reduction potential, or sensitivity to iron chelators. (+info)Measurement in vivo of hydrogenase-catalysed hydrogen evolution in the presence of nitrogenase enzyme in cyanobacteria. (8/323)
A method was devised that allows measurement in vivo of hydrogenase-catalysed H2 evolution from the cyanobacterium Anabaena cylindrica, independent of nitrogenase activity, which is also present. Addition of low concentrations of reduced Methyl Viologen (1-10mM) to intact heterocystous filaments of the organism resulted in H2 evolution, but produced conditions giving total inhibition of nitrogenase (acetylene-reducing and H2-evolving) activity. That the H2 formed under these conditions was not contributed to by nitrogenase was also supported by the observation that its rate of formation was similar in the dark or with Ar replaced by N2 in the gas phase, and also in view of the pattern of H2 evolution at very low Methyl Viologen concentrations. Conclusive evidence that the H2 formed in the presence of Methyl Viologen was solely hydrogenase-mediated was its evolution even from nitrogenase-free (non-heterocystous) cultures; by contrast 'uptake' hydrogenase activity in such cultures was greatly decreased. The hydrogenase activity was inhibited by CO and little affected by acetylene. Finally the hydrogenase activity was shown to be relatively constant at different stages during the batch growth of the organism, as opposed to nitrogenase activity, which varied. (+info)... s are traditionally known as acetylenes, although the name acetylene also refers specifically to C2H2, known formally as ... In acetylene, the H-C≡C bond angles are 180°. By virtue of this bond angle, alkynes are rod-like. Correspondingly, cyclic ... This suffix arose as a collapsed form of the end of the word "acetylene". The final "-e" disappears if it is followed by ... Ethyne is commonly called by its trivial name acetylene. In chemistry, the suffix -yne is used to denote the presence of a ...
Grignard reagents of acetylene or alkynes can be used to perform alkynylations on compounds that are liable to polymerization ... When the acetylide is formed from acetylene, the reaction gives an α-ethynyl alcohol. This process is often referred to as ... The Favorskii reaction is an alternative set of reaction conditions, which involves prereaction of the acetylene with an alkali ... Chemist Walter Reppe pioneered catalytic, industrial-scale ethynylations using acetylene with alkali metal and copper(I) ...
Acetylene zipper. Exceptionally facile contrathermodynamic multipositional isomeriazation of alkynes with potassium 3- ...
Two different examples involve Argon gas and 1,3-butadiene in a mole ratio of 1500:1 Argon gas and acetylene in a mole ratio of ... The laboratory synthesis starts from acetylene C2H2. The reaction takes place within a DC discharge at reduced pressure in a ...
"Acetylene tetrabromide". Immediately Dangerous to Life and Health Concentrations (IDLH). National Institute for Occupational ... acetylene tetrabromide) intoxication in man". American Industrial Hygiene Association. 30 (3): 251-256. doi:10.1080/ ...
"CYCLOPROPYL ACETYLENE". chemicalland21.com. Retrieved 31 May 2017. Hudson, C.E.; Bauld, N.L. (1972). "Quantitative analysis of ...
Acetylene zipper. Exceptionally facile contrathermodynamic multipositional isomeriazation of alkynes with potassium 3- ...
ten Brink, Felix (2014). "Chapter 2. Living on acetylene. A Primordial Energy Source". In Kroneck, Peter M. H.; Sosa Torres, ...
Sahoo, Manoj (2007). "Dimethyl Acetylene Dicarboxylate". Synlett. 2007: 2142. doi:10.1055/s-2007-984894. Bandrowski, E. (1877 ...
acétique) acetylene, (Fr. acétylène) achieve, (Old Fr. achever) achievement, (Fr. achèvement) acid, (Fr. acide) aconite, (Fr. ...
Lighting was originally acetylene. Most of the problems experienced with McKeen cars involved the powerplant and drivetrain. As ...
Reppe's synthesis of cyclooctatetraene, which involves treating acetylene at high pressure with a warm mixture of nickel ... I. Über Cyclooctatetraen" [Ring-forming polymerization of acetylene. I. Cyclooctatetraene]. Liebigs Ann. Chem. 560 (1): 1-92. ... Kunichika, Sango (1953). "Cyclopolyolefins Derived from Acetylene". Bulletin of the Institute for Chemical Research, Kyoto ... one-step synthesis of cyclooctatetraene from acetylene, providing material identical to that prepared by Willstätter. Any ...
Applications of calcium carbide include manufacture of acetylene gas, and for generation of acetylene in carbide lamps; ... Approximately 400,000 tonnes are produced this way annually (see Acetylene Preparation). In China, acetylene derived from ... Locally produced acetylene is more economical than using imported oil. Production of calcium carbide in China has been ... The CaC2 content of the product is assayed by measuring the amount of acetylene produced on hydrolysis. As an example, the ...
232 citations Greaves, E. O.; Lock, C. J. L.; Maitlis, P. M. (1968). "Metal-Acetylene Complexes II. Acetylene Complexes of ... 223 citations Maitlis, P. M. (1976). "The Palladium(II)-Induced Oligomerization of Acetylenes: An Organometallic Detective ...
The headlights used acetylene. A total of 6,575 Oldsmobile vehicles were manufactured in 1909, with 5,325 being the Model 20. ...
Kunichika, Sango (1953). "Cyclopolyolefins Derived from Acetylene". Bulletin of the Institute for Chemical Research, Kyoto ...
Bredig, G.; Usoff, A. (1896). "Ist Acetylen ein Elektrolyt?" [Is acetylene an electrolyte?]. Zeitschrift für Elektrochemie. 3: ... which also contains acetylene and propane. Contrary to the isomerization, initiation of the chain occurs mainly as follows: ( ...
It featured acetylene lighting. A top speed of above 30 mph (48 km/h) was claimed. The monocar was joined in November 1922 by a ...
In this process, acetylene is dimerized to give vinyl acetylene, which is then combined with hydrogen chloride to afford 4- ... Furthermore, the intermediate vinyl acetylene is unstable. This "acetylene process" has been replaced by a process which adds ... Until the 1960s, chloroprene production was dominated by the "acetylene process," which was modeled after the original ... "Acetylene Polymers and their Derivatives. II. A New Synthetic Rubber: Chloroprene and its Polymers". J. Am. Chem. Soc. 53 (11 ...
Wallace H. Carothers, Ira Williams, Arnold M. Collins, and James E. Kirby (1937). "Acetylene Polymers and their Derivatives. II ...
... was produced via the intermediacy of vinyl acetylene. In this process, acetylene is dimerized to give vinyl acetylene, which is ... It also arises via the dimerization of acetylene or dehydrogenation of 1,3-butadiene. At one time, chloroprene (2-chloro-1,3- ... "Acetylene Polymers and their Derivatives. II. A New Synthetic Rubber: Chloroprene and its Polymers". J. Am. Chem. Soc. 53 (11 ...
Young, James K.; Moore, Jeffrey S. (1995). "Chapter 12: Acetylenes in nanostructures". In Stang, P.J.; Diederich, F. Modern ... acetylene chemistry. Weinheim: VCH. pp. 415-418. ISBN 9783527290840. Hill, David J.; Mio, Matthew J.; Prince, Ryan B.; Hughes, ...
Acetylene is a major product; however, it appears C2 will insert into carbon-hydrogen bonds. C2 is 2.5 times more likely to ... Mechanism of acetylene formation from reaction with acetone and acetaldehyde". Journal of the American Chemical Society. 92 (19 ... Diatomic carbon will react with acetone and acetaldehyde to produce acetylene by two different pathways. Triplet C2 molecules ...
Toma - Owns Equipment shop, Acetylene. He is voiced by Rie Kugimiya (Japanese) Richian - Accessory shopkeeper; brother of ...
The preparation of acetylene from calcium carbide. Proc. Chem. Soc. p. 15. 1894. Metallic derivatives of acetylene. I. Mercuric ...
It melts at -80.8°C and boils at -84.0°C. Offensive odors often noted in commercial acetylene are due to impurities. Acetylene ... acetylene (əsĕt´əlēn´) or ethyne (ĕth´īn), HC[triple bond]CH, a colorless gas. ... Acetylene How Products Are Made COPYRIGHT 1996 Gale Research Inc.. Acetylene. Background. Acetylene is a colorless, combustible ... Acetylene Chemical Compounds COPYRIGHT 2006 Thomson Gale. Acetylene. OVERVIEW. Acetylene (uh-SET-ill-ene) is the simplest ...
The substance may polymerize. Decomposes on heating and increasing pressure. This generates fire and explosion hazard. The substance is a strong reducing agent. It reacts violently with oxidants and fluorine or chlorine under influence of light. This generates fire and explosion hazard. Reacts with copper, silver, mercury and their salts. This produces shock-sensitive compounds (acetylides ...
The enzyme acetylene hydratase catalyzes the hydration of acetylene to give acetaldehyde. C2H2 + H2O → CH3CHO Acetylene is a ... Acetylene Production Plant and Detailed Process Acetylene at Chemistry Comes Alive! Acetylene, the Principles of Its Generation ... Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities. As an alkyne, acetylene is ... Since acetylene is a linear symmetrical molecule, it possesses the D∞h point group. At atmospheric pressure, acetylene cannot ...
The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database ...
I. Apparatus and initial observations on acetylene, acetylene-d2, benzene, and benzene-d6, J. Res. NBS, 1964, 68A, 409. [all ... Coats, F.H.; Anderson, R.C., Thermodynamic data from electron-impact measurements on acetylene and substituted acetylenes, J. ... Rosmus, P.; Botschwina, P.; Maier, J.P., On the ionic states of vinylidene and acetylene, Chem. Phys. Lett., 1981, 84, 71. [all ... Shiromaru, H.; Achiba, Y.; Kimura, K.; Lee, Y.T., Determination of the C-H bond dissociation energies of ethylene and acetylene ...
Although the oxy-acetylene processes have been superseded in great measure by modern techniques like M.I.G. welding and plasma- ... Although the oxy-acetylene processes have been superseded in great measure by modern techniques like M.I.G. welding and plasma- ... C. G. Bainbridge and F. Clarke, Oxy-acetylene Welding Repair Manual, B.O.C. Ltd, Waltham Cross, 1968Google Scholar ... BS 1821:1957 Class I oxy-acetylene welding for steel pipelines and pipe assemblies for carrying fluidsGoogle Scholar ...
In enzymology, an acetylene hydratase (EC 4.2.1.112) is a rare example of an enzyme containing tungsten. It catalyzes the ... ten Brink, Felix (2014). "Chapter 2. Living on acetylene. A Primordial Energy Source". In Peter M.H. Kroneck and Martha E. Sosa ... The mechanism is thought to involve attachment of acetylene to the metal followed by nucleophilic attack of water. This enzyme ... The systematic name of this enzyme class is acetaldehyde hydro-lyase (acetylene-forming). Other names in common use include AH ...
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... vinyl acetylene, divinyl acetylene, diacetylene, propadiene, hexadiene, butadienyl acetylene, and methyl acetylene. ... Special Hazards of Acetylene United States Department of Labor.. *Acetylene, the Principles of Its Generation and Use, ... Berthelot oxidized acetylene to yield acetic acid and oxalic acid. He found acetylene could be reduced to form ethylene and ... Acetylene is also used in the acetylene (carbide) lamp, once used by miners (not to be confused with the Davy lamp), on ...
This lack of acetylene is important because that chemical would likely be the best energy source for a methane-based life on ... But Cassini detected no acetylene on the surface. In addition Cassinis spectrometer detected an absence of water ice on the ... One interpretation of the acetylene data is that the hydrocarbon is being consumed as food. But McKay said the flow of hydrogen ... The absence of detectable acetylene on the Titan surface can very well have a non-biological explanation, said Mark Allen, ...
Accurate measurements of trace concentrations of acetylene can be very useful in validating hydrocarbon... ... Acetylene is an important combustion intermediate and plays a critical role in soot formation. ... Mole Fraction Acetylene Shock Tube Absorption Cross Section Reflected Shock Wave This is a preview of subscription content, log ... Acetylene is an important combustion intermediate and plays a critical role in soot formation. Accurate measurements of trace ...
Acetylene, dissolved. Chemical name:. Acetylene. Class:. 2.1. Packaging group:. -. EmS code:. _F-D_, _S-U_. Labels:. Extremely ... Acetylene, dissolved. Chemical name:. Acetylene. Language:. English. Class:. 2. Classification code:. F+ ; R12 ; R5 ;R6. ... Acetylene, dissolved. Chemical name:. Acetylene. Language:. English. Class:. 2. Classification code:. F+; R12. R5, R6. ... Acetylene , dissolved. Chemical name:. Acetylene. Class:. 2.1. Packaging group:. -. Labels:. Extremely flammable. Remarksopen ...
An oxy acetylene torch is an affordable and versatile tool used by many people to heat, weld, solder, and cut metal. It uses ... How to Set Up an Oxy Acetylene Torch. ... Connect the acetylene hose to the acetylene regulator and to ... Fasten oxygen and acetylene cylinders in an upright position. If you have a cylinder cart, place both the oxygen and acetylene ... Reduce the acetylene flow by adjusting the torch acetylene valve. The flame should start to produce black smoke around the ...
OSHA is confirming the effective date of its direct final rule that revises the Acetylene Standard for general industry by ... Therefore, OSHA considers acetylene plants in existence prior to the effective date of NFPA 51A-2001 (i.e., February 9, 2001) ... Revising Standards Referenced in the Acetylene Standard. A Rule by the Occupational Safety and Health Administration on 11/10/ ... Two commenters appeared to confuse the Acetylene Standard at 29 CFR 1910.102, which was the subject of this rulemaking, with ...
acetylenes synonyms, acetylenes pronunciation, acetylenes translation, English dictionary definition of acetylenes. n. A ... acetylene. [əˈsetɪliːn]. A. N → acetileno m. B. CPD acetylene burner N → soplete m oxiacetilénico. acetylene lamp N → lámpara f ... acetylene. [əˈsɛtɪliːn] n → acetilene m. acetylene burner → becco ad acetilene. acetylene welding → saldatura ad acetilene ... acetylene. (redirected from acetylenes). Also found in: Thesaurus, Medical, Encyclopedia.. Related to acetylenes: ethyne ...
The century-old challenge of transporting acetylene may have been solved in principle by a team of scientists working at the ... Exceptionally High Acetylene Uptake in a Microporous Metal - Organic Framework With Open Metal Sites. Journal of the American ... Acetylene, widely used in decades past for welding and illumination, is now also valuable as a starting point for synthesizing ... To safely store acetylene, storage cylinders have to be filled with both porous material and liquid solvents such as acetone. ...
https://wilhelmsen.com/product-catalogue/application-areas/container/engine-room/workshop/gases/oxygen-acetylene-cutting/ ...
Regulator: acetylene. • Tank type: B. • CGA tank connection: 520. • Dual or Single stage: single. • Number of gauges: two. • ...
Reports emphasize significant developments in process technology for Acetylene that have potential implications for the ... Also in this report, SRI evaluates the technology of recovering the acetylene that is by-produced in ethylene production and ... Acetylene vs Ethylene as a Chemical Raw Material - Chemical production and investment cost ... The thermal cracking process for producing acetylene, once widely used, has been abandoned. The submerged flame process was ...
Series Title: PPI: Other industrial gases (including fluorocarbon and acetylene); NSA For this series: Numerical Data , Source ... Series Title: PPI: Other industrial gases (including fluorocarbon and acetylene); NSA For this series: Numerical Data , ...
The Global Acetylene Industry 2015 Market Research Report is a professional and in-depth study on the - Market Research Reports ... 1.2 Classification of Acetylene. 1.3 Applications of Acetylene. 1.4 Industry Chain Structure of Acetylene. 1.5 Industry ... Table Specifications of Acetylene. Table Classification of Acetylene. Figure Global Production Market Share of Acetylene by ... 1.5.1 Industry Overview of Acetylene. 1.5.2 Global Major Regions Status of Acetylene. 1.6 Industry Policy Analysis of Acetylene ...
Acetylene is colorless and extremely unstable in its pure form, which is why it is ... Acetylene is a hydrocarbon compound and is the simplest form of alkyne. ... What is an Acetylene Torch?. Acetylene is a hydrocarbon compound and is the simplest form of alkyne. Acetylene is colorless and ... What is an Acetylene Torch?. An acetylene torch is a hand-held torch with one or two hoses that connect to two separate gas ...
What do you think of Acetylene-Air torches? - Im thinking of branching out from silversmithery into building a couple of ... What do you think of Acetylene-Air torches? Im thinking of branching out from silversmithery into building a couple of frames ... and I was wondering if acetylene-air is adequate for brazing a frame. I have a Presto-lite with #2 (itsy)-#5 (1/4 inch) tips. ...
Find Acetylene Oxygen Co Inc located at 11446 Hempstead Rd, Houston, Texas, 77092. Contact 7136811782. Ratings, reviews, hours ... For maps and directions to Acetylene Oxygen Co Inc view the map to the right. For reviews of Acetylene Oxygen Co Inc see below. ... Acetylene Oxygen Co Inc is located at the address 11446 Hempstead Rd in Houston, Texas 77092. They can be contacted via phone ... Acetylene Oxygen Co Inc provides Repairs & Replacements, Fabrication, Demolition to its customers. ...
C2H2EthyneHydrogenOxygen acetyleneProduce acetyleneHydrocarbonHydration of acetyleneTorch2018WeldingAlkyneMixture of oxygen and acetyleneVinyl chlorideDiscovered in 1836ReactionMethylEthylenePyrolysisBenzene and acetyleneCylinderHydrataseAtmosphericMoleculesSynthesisColorlessInitial acetyleneUptakeAcetaldehydeIndustrially significant chemicalsAromaticCarbideCompoundsCatalystsCatalystCylindersCentersFlammableTanksFlameNitrogenCombustionAcetoneMoleculeReactionsChemistryPhenylElectrophilicNitrogenase activityTorchesBerthelotOrganicCalciumSituSuppliersConsumptionTemperaturesInhibitionPolyimideVibrationalPolymerExplosiveNIOSHImpuritiesAdsorption
- Acetylene (systematic name: ethyne) is the chemical compound with the formula C2H2. (wikipedia.org)
- It catalyzes the hydration of acetylene to give acetaldehyde: C2H2 + H2O → CH3CHO The W centre is bound to two molybdopterin cofactors. (wikipedia.org)
- Acetylene (C2H2) inhibits key enzymes involved in nitrification (Ammonium monooxygenase) and denitrification (N2O reductases). (nih.gov)
- What mass of acetylene, C2H2, will be produced for the reaction of 90.g of calcium carbide, CaC2, with water in the following reacion? (jiskha.com)
- Calcium carbide (CaC2) reacts with water to form acetylene (C2H2) gas and calcium hydroxide (Ca(OH)2). (jiskha.com)
- Acetylene gas, C2H2, and solid calcium hydroxide were formed by the reaction of calcium carbide, CaC2, with water. (jiskha.com)
- In this study, we investigated the effects of specific bacteria- and eukaryote-selective protein synthesis inhibitors on the recovery of acetylene (C2H2)-inactivated NH3 oxidation in the marine AOA Nitrosopumilus maritimus and compared the results with recovery of the AOB Nitrosomonas europaea. (ovid.com)
- acetylene (əsĕt´əlēn´) or ethyne (ĕth´īn) , HC[triple bond]CH, a colorless gas. (encyclopedia.com)
- What is acetylene (ethyne) used for? (bartleby.com)
- Acetylene was discovered in 1836 by Edmund Davy, who identified it as a "...new carburet of hydrogen. (wikipedia.org)
- Berthelot's empirical formula for acetylene (C4H2), as well as the alternative name "quadricarbure d'hydrogène" (hydrogen quadricarbide) were incorrect because chemists at that time used the wrong atomic mass for carbon (6 instead of 12). (wikipedia.org)
- He also found acetylene was formed by sparking electricity through mixed cyanogen and hydrogen gases. (wikipedia.org)
- Berthelot later obtained acetylene directly by passing hydrogen between the poles of a carbon arc. (wikipedia.org)
- Commercially available acetylene gas could smell foul due to the common impurities hydrogen sulfide and phosphine. (wikipedia.org)
- With alcohols, hydrogen cyanide, hydrogen chloride, or carboxylic acids to give vinyl compounds: With carbonyl groups to give α-ethynyl alcohols in ethynylation reactions: 1,4-Butynediol is produced industrially in this way from formaldehyde and acetylene. (wikipedia.org)
- He was also able to form acetylene directly by combining pure hydrogen with carbon using electrical discharge of a carbon arc. (newworldencyclopedia.org)
- What is Consuming Hydrogen and Acetylene on Titan? (nasa.gov)
- Previous models had predicted that hydrogen molecules, a byproduct of ultraviolet sunlight breaking apart acetylene and methane molecules in the upper atmosphere, should be distributed fairly evenly throughout the atmospheric layers. (nasa.gov)
- The Titan surface is also so cold that a chemical process that involved a catalyst would be needed to convert hydrogen molecules and acetylene back to methane, even though overall there would be a net release of energy. (nasa.gov)
- While the term "acetylene torch" can be used to refer specifically to a torch that uses acetylene, it can also describe any oxy-fuel torch in general in which other gases such as propylene, hydrogen, propane, natural gas, liquefied petroleum gas, or MAPP gas can be used. (tech-faq.com)
- This suggests that the suicide inhibition of P450s by propynylaryl acetylenes proceeds via a methylaryl ketene formed by a 1,2-methyl rearrangement, analogous to the mechanism of suicide inhibition by ethynyl acetylenes that proceed via ketene intermediates formed by 1,2-hydrogen shifts [Ortiz de Montellano, P. R., and Kunze, K. L. (1981) Arch. (nih.gov)
- The Little Torch has unmatched flexibility - it can be used with several fuels including acetylene, hydrogen, propane, propylene, or natural gas. (weldfabulous.com)
- Clarification of 29 CFR 1926.350(b)(4) to Permit Cylinders Containing Oxygen, Acetylene or Other Fuel Gas to be Taken into Tunnels. (osha.gov)
- This twin-line oxygen/acetylene hose assembly has two hoses: a green hose for carrying oxygen to welding equipment, and a red hose for carrying acetylene to welding equipment. (unitedrentals.com)
- All oxygen acetylene bottles wholesalers & oxygen acetylene bottles manufacturers come from members. (benadorassociates.com)
- We doesn't provide oxygen acetylene bottles products or service, please contact them directly and verify their companies info carefully. (benadorassociates.com)
- Hazards of Oxygen-Acetylene One potentially hazardous practice is the use of oxygen-acetylene (oxygen fuel) torches and welders, which have been under scrutiny for some time. (theinductor.com)
- Flames can be the cause of many accidents in the workshop, but what are the realistic alternatives to using a naked, oxygen fuel (oxygen-acetylene) flame? (theinductor.com)
- Calcium carbide (or calcium acetylide) and water are then reacted by any of several methods to produce acetylene and calcium hydroxide. (newworldencyclopedia.org)
- Scientists had expected the sun's interactions with chemicals in the atmosphere to produce acetylene that falls down to coat the Titan surface. (nasa.gov)
- Calcium carbide (CaC2) reacts with water to produce acetylene as follows. (jiskha.com)
- Above 400 °C(673 K) (which is quite low for a hydrocarbon), the pyrolysis of acetylene will start. (newworldencyclopedia.org)
- One interpretation of the acetylene data is that the hydrocarbon is being consumed as food. (nasa.gov)
- Accurate measurements of trace concentrations of acetylene can be very useful in validating hydrocarbon oxidation and soot formation mechanisms. (springer.com)
- Acetylene is a hydrocarbon compound and is the simplest form of alkyne. (tech-faq.com)
- We have focused on acetylene, the third most abundant hydrocarbon in Titan s atmosphere after CH 4 and C 2 H 6 . (astrobiology.com)
- Further, acetylene is the most abundant unsaturated hydrocarbon in Titan s atmosphere. (astrobiology.com)
- The lightest Non Methane HydroCarbon (NMHC), i.e., acetylene (C 2 H 2 ) is found to form secondary organic aerosol (SOA). (atmos-chem-phys.net)
- Catalyzes the hydration of acetylene to form acetaldehyde. (mybiosource.com)
- The hydration of acetylene results in acetaldehyde, CH 3 CHO, the starting material for production of acetic and other acids. (thefreedictionary.com)
- An oxy acetylene torch is an affordable and versatile tool used by many people to heat, weld, solder, and cut metal. (wikihow.com)
- Using pressure-reducing regulators, connecting gas supplies, and safely lighting the torch flame are all essential parts of learning how to use an oxy acetylene torch. (wikihow.com)
- The regulators let you see how much pressure you're using while working and are essential to safely starting and operating an oxy acetylene torch. (wikihow.com)
- What is an Acetylene Torch? (tech-faq.com)
- An acetylene torch is a hand-held torch with one or two hoses that connect to two separate gas tanks. (tech-faq.com)
- In welding, two pieces of metal are pressed together while a welder or welding machine uses an acetylene torch to concentrate heat on the point where the two metals touch. (tech-faq.com)
- The welder then shuts off the acetylene torch and allows the liquid metal to cool and turn back into a solid. (tech-faq.com)
- In this scenario, an acetylene torch is used to heat the metal to a kindling temperature while a stream of pure oxygen is applied to the desired area. (tech-faq.com)
- I have an oxy-acetylene tank for my mig welder but haven't done anything with a cutting torch. (weldingweb.com)
- It is used for cutting and welding metals (see oxyacetylene torch oxyacetylene torch , tool that mixes and burns oxygen and acetylene to produce an extremely hot flame. (thefreedictionary.com)
- Acetylene-dicarboxylic acid (CAS 142-45-0) Market Research Report 2018 contents were prepared and placed on the website in January, 2018. (marketpublishers.com)
- Please note that Acetylene-dicarboxylic acid (CAS 142-45-0) Market Research Report 2018 is a half ready publication and contents are subject to change. (marketpublishers.com)
- 1-Phenyl-2-(trimethylsilyl)-acetylene (CAS 2170-06-1) Market Research Report 2018 contents were worked out and placed on the website in February, 2018. (marketpublishers.com)
- Please note that 1-Phenyl-2-(trimethylsilyl)-acetylene (CAS 2170-06-1) Market Research Report 2018 is a half ready publication and contents are subject to change. (marketpublishers.com)
- Albany, US, 2018-Mar-06 - /EPR Network/ - An up-to-date research report has been disclosed by Market Research Hub highlighting the title " Global Acetylene Black Market Report 2018 " which provides an outlook of current market growth as well as the expected forecast including Rate on Investment (ROI) together with growing CAGR near XX% during 2018-2025. (express-press-release.net)
- The Global Acetylene Cylinder was valued at USD xx million in 2017 and is forecasted to reach USD xx million by 2025, with a CAGR of xx% during the forecast period (2018-2025). (stetsonreporter.com)
- car manufacturers, for instance, still use the process and almost every garage and small workshop has its oxy-acetylene welding and cutting equipment. (springer.com)
- Acetylene, widely used in decades past for welding and illumination, is now also valuable as a starting point for synthesizing a range of chemicals used in plastics and explosives. (scienceblog.com)
- Acetylene was once the preferred gas in welding/cutting applications due to its ability to reach extremely high temperatures (3300 degrees Celsius/6000 degrees Fahrenheit) when mixed with oxygen. (tech-faq.com)
- Acetylene is widely used for welding purposes, although it is not as common as it once was. (tech-faq.com)
- Worker in heavy heat-resistant protective clothing holding oxy-acetylene welding equipment. (sciencephoto.com)
- The purpose of this page is to introduce the beginning welder to the equipment used in the Oxy-Acetylene welding process. (voortrekker-history.co.za)
- ADVERTISEMENTS: This article throws light upon the ten basic equipment's used for oxy-acetylene welding. (voortrekker-history.co.za)
- Old oxygen and acetylene tanks and welding equipment along with an old Plymouth van . (collinsdictionary.com)
- As an alkyne, acetylene is unsaturated because its two carbon atoms are bonded together in a triple bond. (wikipedia.org)
- Acetylene is the simplest alkyne . (encyclopedia.com)
- Finally, sulfonyl acetylenes are efficient for alkyne transfer on carbon-centered radicals. (epfl.ch)
- Acetylene is the simplest alkyne alkyne , any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon triple bonds (see chemical bond). (thefreedictionary.com)
- This equipment burns a mixture of oxygen and acetylene, allowing a flame temperature of about 3300 degrees Celsius to be attained. (sciencephoto.com)
- The competitive position of acetylene relative to ethylene in vinyl chloride and vinyl acetate production and relative to propylene in acrylic acid production is described. (ihs.com)
- The mercuric chloride catalyst for acetylene hydrochlorination creates vinyl chloride, an important polymer feedstock. (sciencemag.org)
- A Ru-based catalyst (Ru/N-AC) was prepared using N-doped carbon as the support and the catalytic performance of the one-step synthesis reaction of vinyl chloride monomer (VCM) from acetylene and 1,2-dichloroethane (EDC) was assessed. (rsc.org)
- Acetylene was discovered in 1836, when Edmund Davy was experimenting with potassium carbide. (voortrekker-history.co.za)
- Acetylene is easily prepared commercially by the reaction of calcium carbide with water, but is prepared commercially by the pyrolysis of hydrocarbons. (encyclopedia.com)
- The developed reaction conditions led to high yields of unprotected acetylenes with cyclic, nitro and linear keto esters as well as keto amides. (epfl.ch)
- This allows a new direct access to chiral acetylene compound in high yields under operationally simple reaction conditions. (epfl.ch)
- In many instances, the reaction sequence regiospecifically ligates azides and terminal acetylenes to give only 1,4-disubstituted [1,2,triazoles. (freepatentsonline.com)
- We have performed an in situ x-ray absorption fine structure study of gold/carbon (Au/C) catalysts under acetylene hydrochlorination reaction conditions and show that highly active catalysts comprise single-site cationic Au entities whose activity correlates with the ratio of Au(I):Au(III) present. (sciencemag.org)
- The making of acetylene gas from the reaction of water with calcium carbide has long been known. (voortrekker-history.co.za)
- The physical and CO 2 permeation properties of its crosslinked membranes prepared by the cyclotrimerization reaction of the acetylene groups at the polymer chain end using tantalum (V) chloride (TaCl 5 ) as a catalyst under thermal treatment was investigated in terms of CO 2 -induced membrane plasticization. (wiley.com)
- The cyclotrimerization reaction of the acetylene groups at the polymer chain ends using a transition metal catalyst under thermal treatment was found to be more effective than conventional thermal treatments for suppressing membrane plasticization without the membrane densification. (wiley.com)
- Development on new intermolecular reductive cyclized reaction of acetylenes and its development to the material science. (worldwidescience.org)
- Through BET, TG, XPS, ICP, TPR, TPD, TEM and XRD characterization, it is indicated that N-doped AC support can increase the amount of RuO 2 and RuO x species in the catalyst and enhance its adsorption ability for both EDC and acetylene, suggesting that the N dopant and Ru species generated a synergistic effect in the one-step synthesis reaction of VCM. (rsc.org)
- Acetylene (C 2 H 2 ) can be produced from the reaction of calcium carbide (CaC 2 ) with water. (bartleby.com)
- No. 3,845,018 and is a multi-step procedure involving the initial reaction of an aromatic tetracarboxylic acid dianhydride such as benzophenone tetracarboxylic acid dianhydride with an aromatic diamine to form an anhydride-capped polyamic acid, which is subsequently reacted with an aminoarylacetylene to produce an acetylene-terminated polyamic acid oligomer, which is then thermally converted to the desired acetylene-substituted polyimide oligomer. (google.com)
- If the acetylene were burned to form water and carbon dioxide, how many kilojoules of energy would be produced from the complete reaction of 20 of calcium carbide? (jiskha.com)
- Acetylene is easily prepared commercially by the reaction of calcium carbide carbide, any one of a group of compounds that contain carbon and one other element that is either a metal, boron, or silicon. (thefreedictionary.com)
- Berthelot was able to prepare acetylene from methyl alcohol, ethyl alcohol, ethylene , or ether , when he passed any one of these as a gas or vapor through a red-hot tube. (newworldencyclopedia.org)
- The polyamic acid oligomer is thereafter converted to the desired acetylene-terminated polyimide oligomer by heating in the continued presence of said N-methyl-2-pyrrolidone. (google.com)
- The N-methyl-2-pyrrolidone can then be removed by any suitable means such as by precipitation of the acetylene-substituted polyimide oligomer in a non-solvent such as ethanol. (google.com)
- citation needed] Since the 1950s, acetylene has mainly been manufactured by the partial combustion of methane or appears as a side product in the ethylene stream from cracking of hydrocarbons. (wikipedia.org)
- He found acetylene could be reduced to form ethylene and ethane . (newworldencyclopedia.org)
- In the late 1990s, because of the pressure exerted on the cost of ethylene by the increasing price of oil, interest in the long-dormant subject of acetylene production was renewed. (ihs.com)
- Also in this report, SRI evaluates the technology of recovering the acetylene that is by-produced in ethylene production and compares the economics of recovery with that of hydrogenation. (ihs.com)
- The usage of ethylene and acetylene are to be described. (bartleby.com)
- According to the C-C bond lengths obtained, the adsorbed molecule was modified from acetylene-like into ethylene-like on the δ-MoC(001) surface (desired behavior for hydrogenation reactions) but into ethane-like on TiC(001) and ZrC(001). (osti.gov)
- The diagnostic is demonstrated by measuring acetylene formation during the shock-heated pyrolysis and oxidation of propene. (springer.com)
- These materials have been used as catalytic templates for the production of carbon nanotubes (CNTs) by acetylene pyrolysis at atmospheric pressure. (ad-astra.ro)
- The rotational spectrum of the CH$\cdots\pi$ bonded complex between benzene and acetylene has been measured in the $6-20$ GHz range using chirped-pulse Fourier-transform microwave spectroscopy. (illinois.edu)
- Various configurations of the system composed of benzene and acetylene are investigated in an effort to identify the most stable. (usu.edu)
- If you have a cylinder cart, place both the oxygen and acetylene cylinders into it. (wikihow.com)
- The analysis showed that the acetylene attaches to the exposed copper by virtue of weak electrical charges, allowing the MOF to store 201 cubic centimeters of acetylene per gram of lattice at ambient pressure - comparable to the amount of similar chemicals that can be contained within a high pressure storage cylinder. (scienceblog.com)
- Acetylene Cylinder 3. (voortrekker-history.co.za)
- Global Acetylene Cylinder Market reports provide a valuable source of insightful data for business strategists and competitive analysis of Acetylene Cylinder Market. (stetsonreporter.com)
- It provides the Acetylene Cylinder industry overview with growth analysis and futuristic cost, revenue, demand and supply data. (stetsonreporter.com)
- This Acetylene Cylinder Market study provides comprehensive data which enhances the understanding, scope and application of this report. (stetsonreporter.com)
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- 5. The report helps you to understand the real effects of key market drivers or restrainers on Acetylene Cylinder business. (stetsonreporter.com)
- In enzymology, an acetylene hydratase (EC 4.2.1.112) is a rare example of an enzyme containing tungsten. (wikipedia.org)
- Acetylene hydratase participates in tetrachloroethene degradation. (wikipedia.org)
- therefore, C 2 H 2 consumption could be attributed to acetylene hydratase (AH) rather than nitrogenase activity. (usgs.gov)
- Below are the list of possible Acetylene hydratase products. (mybiosource.com)
- Also known as Acetylene hydratase (Ahy). (mybiosource.com)
- At atmospheric pressure, acetylene cannot exist as a liquid and does not have a melting point. (wikipedia.org)
- The sublimation point at atmospheric pressure is −84.0 °C. The adiabatic flame temperature in air at atmospheric pressure is 2534 °C.[citation needed] Acetylene gas can be dissolved in acetone or dimethylformamide in room temperature and 1 atm. (wikipedia.org)
- In the United States alone, several hundred thousand tons of acetylene are produced every year, but its volatility renders it difficult to transport: It becomes dangerously explosive at about 30 psi (207 kilopascal), only about twice normal atmospheric pressure. (scienceblog.com)
- In our work, stable carboxyl-rich plasma polymers (COOH PPs) were deposited using plasma co-polymerization of maleic anhydride and acetylene at atmospheric pressure using dielectric barrier discharge (DBD). (muni.cz)
- 4 CO2 + 2 H2O, two molecules of acetylene combine with five compounds of two bonded oxygen atoms to form four molecules of carbon dioxide and two molecules of water. (reference.com)
- We observed that about 15% of the initial acetylene is photodesorbed, with a photodesorption rate of (2.1 +/- 0.2) x 10-6 molecules.photon-1 at 355 nm. (astrobiology.com)
- Approximately 80 percent of the acetylene produced annually in the United States is used in chemical synthesis. (newworldencyclopedia.org)
- This constitutes a serious limitation, in particular when considering that "classical" C-C bond formation is not adequate for the synthesis of quaternary centers containing an acetylene. (epfl.ch)
- Some commercially useful acetylene compounds include acetylene black, which is used in certain dry-cell batteries, and acetylenic alcohols, which are used in the synthesis of vitamins. (voortrekker-history.co.za)
- Trimethylsilyl)acetylene is used in the preparation of trimethylsilanyl-propiolic acid ethyl ester by reacting with carbonochloridic acid ethyl ester as well as in the synthesis of iodoalkenes by radical addition of perfluoroalkyl iodides. (alfa.com)
- Synthesis routes of novel piperidine-containing acetylenes are presented. (diva-portal.org)
- Acetylene is colorless and extremely unstable in its pure form, which is why it is almost always mixed with other chemicals and handled as a solution. (tech-faq.com)
- It is indicated that 1% Ru/N-AC exhibited good catalytic activity with an initial acetylene conversion of 95.2% at 250 °C, an EDC total liquid hourly space velocity (LHSV) of 0.2 h −1 and a molar ratio n (EDC)/ n (C 2 H 2 ) of 1, much better than that of 1% Ru/AC or N-AC. (rsc.org)
- Exceptionally High Acetylene Uptake in a Microporous Metal - Organic Framework With Open Metal Sites. (scienceblog.com)
- Comparison and reliability of two non-invasive acetylene uptake techniques for the measurement of cardiac output. (biomedsearch.com)
- Thirteen trained male cyclists performed CO2 rebreathing (CO2RB) at intensities from rest to 200 W, and open-circuit acetylene uptake (OpCirc) and single-breath acetylene uptake (SB) at intensities from rest to 300 W, with all procedures using 50 W increments. (biomedsearch.com)
- The systematic name of this enzyme class is acetaldehyde hydro-lyase (acetylene-forming). (wikipedia.org)
- Walter Reppe discovered that in the presence of metal catalysts, acetylene can react to give a wide range of industrially significant chemicals. (wikipedia.org)
- Until the 1950s, when oil supplanted coal as the chief source of reduced carbon, acetylene (and the aromatic fraction from coal tar) was the main source of organic chemicals in the chemical industry. (wikipedia.org)
- Using acetylene, Berthelot was the first to show that an aliphatic compound could form an aromatic compound when he heated acetylene in a glass tube to produce benzene with some toluene . (newworldencyclopedia.org)
- Acetylene is also used in the acetylene ('carbide') lamp, once used by miners (not to be confused with the Davy lamp), on vintage cars , and still sometimes used by cavers. (newworldencyclopedia.org)
- In this context, the acetylene is generated by dripping water from the upper chamber of the lamp onto calcium carbide (CaC 2 ) pellets in the base of the lamp. (newworldencyclopedia.org)
- It was found that the bonding of acetylene was significantly affected by the electronic and structural properties of the carbide surfaces. (osti.gov)
- The synthetic potential of propargylic nitro compounds bearing free acetylenes was demonstrated by their transformation into propargylic triazoles, hydroxylamines and protected amines, as well as into allyl amines in good yield. (epfl.ch)
- The chlorination of acetylene is the basis for obtaining trichloroethylene, tetrachloroethane, and other compounds containing chlorine. (thefreedictionary.com)
- Polymerization of acetylene with Ziegler-Natta catalysts produces polyacetylene films. (newworldencyclopedia.org)
- Processes and catalysts used in the selective hydrogenation of dienes and acetylenes. (google.com)
- There remains considerable debate over the active form of gold under operating conditions of a recently validated gold catalyst for acetylene hydrochlorination. (sciencemag.org)
- Fasten oxygen and acetylene cylinders in an upright position. (wikihow.com)
- Connect the oxygen and acetylene regulators to their cylinders. (wikihow.com)
- To safely store acetylene, storage cylinders have to be filled with both porous material and liquid solvents such as acetone. (scienceblog.com)
- 29 CFR 1926.350(b)(4) states: "Cylinders containing oxygen or acetylene or other fuel gas shall not be taken into confined spaces. (osha.gov)
- Always comply with all local regulations governing the transport of cylinders in vehicles and the safe unloading and storage of acetylene cylinders. (boconline.co.uk)
- Read the latest operational guidance on dealing with acetylene cylinders involved in fires. (boconline.co.uk)
- Our results indicate that the aerosols can act as activation centers to drive the photoreactivity of acetylene with the aerosols at the accretion interface at wavelengths where acetylene-ice alone does not show photoreactivity. (astrobiology.com)
- Because acetylene is so flammable and has a 29 PSI, it cannot be used in underwater applications or other applications that involve high pressure. (tech-faq.com)
- Forgot what the capacity of tanks are-Oxygen about 3 feet tall, Acetylene about 2-1/2 foot tall. (northwestfirearms.com)
- combustion of acetylene with oxygen produces a flame of over 3300 °C (6000 °F), releasing 11.8 kJ/g. (newworldencyclopedia.org)
- Acetylene produces the third hottest natural chemical flame, after cyanogen (4525 degrees Celsius) and dicyanoacetylene (4990 degrees Celsius). (tech-faq.com)
- Acetylene is a colourless gas which burns with a very hot bright flame . (collinsdictionary.com)
- To: Oxygen, Nitrogen, Acetylene And Other Gas Plants ( Dalal Mckenna Pvt.ltd. (eindiabusiness.com)
- Acetylene can also be manufactured by the partial combustion of methane with oxygen , or by the cracking of hydrocarbons . (newworldencyclopedia.org)
- Acetylene is an important combustion intermediate and plays a critical role in soot formation. (springer.com)
- What is the balanced equation for the complete combustion of acetylene? (reference.com)
- Removes particulate and acetone droplets from acetylene to 99.99% at 0.1 micron protecting your microcomputer gas controls and AA burner system from contamination and corrosion. (perkinelmer.com)
- it is only slightly soluble in water and very soluble in acetone (at 15°C, 25 parts of acetylene to 1 part of acetone). (thefreedictionary.com)
- Since acetylene is a linear symmetrical molecule, it possesses the D∞h point group. (wikipedia.org)
- The consecutive ion-molecule reactions in acetylene within the pressure limits of 0.00001 and 0.01 torr have been investigated as a function of the energy transferred to the acetylene molecule during the initial ionization by charge exchange with incident positive ions of low kinetic energy. (dtic.mil)
- Despite many interesting and useful reactions of acetylenes with superbases the most amazing is the "contrathermodynamic" multipositional isomerization of the internal triple bond to the terminal position under the influence of alkali metal amides of ethylenediamine or 1,3-propylenediamine. (thefreedictionary.com)
- Reactions of acetylenes with noble-metal halides. (alfa.com)
- In addition to the well-established nucleophilic alkynylation, the use of electrophilic alkynes can expand tremendously the scope of acetylene transfer reactions. (epfl.ch)
- Acetylenes are versatile intermediates in chemistry, biochemistry and material sciences. (epfl.ch)
- A metal catalyzed click chemistry ligation process is employed to bind azides and terminal acetylenes to give triazoles. (freepatentsonline.com)
- The report generally describes 1-phenyl-2-(trimethylsilyl)-acetylene, examines its uses, production methods, patents. (marketpublishers.com)
- 1-phenyl-2-(trimethylsilyl)-acetylene manufacturers and suppliers with contacts and product range are mentioned in the study. (marketpublishers.com)
- Furthermore, 1-phenyl-2-(trimethylsilyl)-acetylene prices in regional markets can be found in the report with regards to countries and companies. (marketpublishers.com)
- The report also focuses on 1-phenyl-2-(trimethylsilyl)-acetylene consumers by providing data on companies that use it. (marketpublishers.com)
- However, the reverse approach (Umpolung of the reactivity) via an electrophilic acetylene synthon has been more rarely used. (epfl.ch)
- Halogenoalkynes, hypervalent alkynyliodoniums, acetylene sulfones and in situ oxidized terminal acetylenes are the most often used reagents for electrophilic alkynylation. (epfl.ch)
- For C-C bond formation, electrophilic acetylenes can be coupled with different organometallic reagents. (epfl.ch)
- Ribet, J. and Drevon, J.-J. (1995) Phosphorus Deficiency Increases the Acetylene-Induced Decline in Nitrogenase Activity in Soybean (Glycine max (L.) Merr. (scirp.org)
- Acetylene torches and acetylene itself have several distinct advantages. (tech-faq.com)
- What do you think of Acetylene-Air torches? (bikeforums.net)
- It was rediscovered in 1860 by French chemist Marcellin Berthelot, who coined the name "acetylene. (newworldencyclopedia.org)
- Berthelot oxidized acetylene to yield acetic acid and oxalic acid. (newworldencyclopedia.org)
- Acetylene is an unsaturated organic compound because its four atoms are triple bonded through a covalent bond . (newworldencyclopedia.org)
- The team has probed the atomic-level workings of a metal-organic framework (MOF), a lattice-like structure made of copper oxide and benzene, that soaks up acetylene like a sponge. (scienceblog.com)
- The principal raw materials for acetylene manufacture are calcium carbonate ( limestone ) and coal . (newworldencyclopedia.org)
- F to form a hard porous mass suitable for containing dissolved acetylene gas solutions, comprising lime, crystalline silica, and a thickening agent selected from the group consisting of (a) polyethylene oxide, (b) amorphous glassy silica, (c) a soluble salt of phosphate and a soluble salt of calcium and (d) a soluble salt of phosphate and a neutralizing acid. (patentgenius.com)
- An apparatus was designed that permitted acetylene reduction (N 2 fixation) by root nodules to be measured in situ simultaneously with net photosynthesis, dark respiration, and transpiration of the shoot in soybean plants ( Glycine max [L.] Merr. (plantphysiol.org)
- acetylene-dicarboxylic acid manufacturers and suppliers with contacts and product range are mentioned in the study. (marketpublishers.com)
- Among them, metal oxides have become important candidates for acetylene sensing due to their unique advantages-such as their small size and simplicity of integration-but they lack selectivity towards different gas species, and often require high operating temperatures and have high power consumption [ 16 , 17 , 18 , 19 , 20 ]. (mdpi.com)
- At temperatures below the triple point, solid acetylene can change directly to the vapour (gas) by sublimation. (wikipedia.org)
- Experiments are carried out behind reflected shock waves to measure absorption cross sections of acetylene near 730 cm −1 over a wide range of temperatures (1000-2200 K) and pressures (1-5 bar). (springer.com)
- The acetylene sensing properties were investigated using different working temperatures and gas concentrations. (mdpi.com)
- Many of the acetylenes investigated produce pseudo-first-order time-dependent and NADPH-dependent losses of the dealkylation activities characteristic of mechanism-based irreversible inactivation (suicide inhibition). (nih.gov)
- Consequently, it was concluded that photosynthesis, transpiration, or some direct effect on the nodules other than that caused by respiration were most likely to account for the inhibition of acetylene reduction at soil water potentials below −2 bars. (plantphysiol.org)
- A novel fluorine-containing telechelic polyimide end-capped with acetylene group which derived from 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), 3,4-diaminodiphenyl ether (DADE), and 4-(2-phenylethynyl) phthalic anhydride (PEPA) was synthesized using polycondensation. (wiley.com)
- A method of homopolymerizing the acetylene-substituted polyimide oligomers described in the U.S. Pat. (google.com)
- Strongest vibrational band of acetylene near 13.7 μm is probed here to develop a highly sensitive absorption diagnostic. (springer.com)
- The anharmonic interaction coupling terms known to occur from a pure vibrational fit in this acetylene isotopologue are included in the model. (osu.edu)
- entitled "POLYMERIC MATERIAL MADE FROM SILOXANE-ACETYLENE POLYMER CONTAINING METAL-ACETYLENE COMPLEX," designated as NC 97,123, and filed on the same day as the present application is incorporated by reference. (google.com)
- Acetylene forms explosive mixtures with oxygen or air. (encyclopedia.com)
- However, acetylene is unstable and there is a huge potential risk of fire or explosive accidents during its compression and heat treatment, or due to leakage. (mdpi.com)
- A mixture of acetylene with air (2.3-80.7 percent acetylene by volume) is explosive. (thefreedictionary.com)
- Section 8: Exposure Controls/Personal Protection Exposure Guidelines ACETYLENE, DISSOVED: ACETYLENE: ACGIH (simple asphyxiant) 2500 ppm (2662 mg/m3) NIOSH recommended ceiling Engineering Controls Handle only in fully enclosed systems or with adequate ventilation. (voortrekker-history.co.za)
- Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities. (wikipedia.org)
- It melts at -80.8°C and boils at -84.0°C. Offensive odors often noted in commercial acetylene are due to impurities. (encyclopedia.com)
- Offensive odors often noted in commercial acetylene are due to impurities. (thefreedictionary.com)
- A comprehensive study of acetylene adsorption on δ-MoC(001), TiC(001) and ZrC(001) surfaces was carried out by means of calculations based on periodic density functional theory, using the Perdew-Burke-Ernzerhof exchange-correlation functional. (osti.gov)
- The interaction of acetylene with the TiC(001) and ZrC(001) surfaces was strong (binding energies higher than $-$3.5 eV), while moderate acetylene adsorption energies were observed on δ-MoC(001) ($-$1.78 eV to -0.66 eV). (osti.gov)