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22,500 | Ammonia is directly or indirectly the precursor to most nitrogen-containing compounds. Virtually all synthetic nitrogen compounds are derived from ammonia. An important derivative is nitric acid. This key material is generated via the Ostwald process by oxidation of ammonia with air over a platinum catalyst at , ≈9 atm... | https://en.wikipedia.org/wiki?curid=1365 |
22,501 | Nitric acid is used for the production of fertilizers, explosives, and many organonitrogen compounds. | https://en.wikipedia.org/wiki?curid=1365 |
22,502 | Ammonia can also be used to make compounds in reactions which are not specifically named. Examples of such compounds include: ammonium perchlorate, ammonium nitrate, formamide, dinitrogen tetroxide, alprazolam, ethanolamine, ethyl carbamate, hexamethylenetetramine, and ammonium bicarbonate. | https://en.wikipedia.org/wiki?curid=1365 |
22,503 | Household "ammonia" (more correctly called ammonium hydroxide) is a solution of in water, and is used as a general purpose cleaner for many surfaces. Because ammonia results in a relatively streak-free shine, one of its most common uses is to clean glass, porcelain and stainless steel. It is also frequently used for cl... | https://en.wikipedia.org/wiki?curid=1365 |
22,504 | Solutions of ammonia (5–10% by weight) are used as household cleaners, particularly for glass. These solutions are irritating to the eyes and mucous membranes (respiratory and digestive tracts), and to a lesser extent the skin. Experts advise that caution be used to ensure the substance is not mixed into any liquid con... | https://en.wikipedia.org/wiki?curid=1365 |
22,505 | Experts also warn not to use ammonia-based cleaners (such as glass or window cleaners) on car touchscreens, due to the risk of damage to the screen's anti-glare and anti-fingerprint coatings. | https://en.wikipedia.org/wiki?curid=1365 |
22,506 | Solutions of ammonia ranging from 16% to 25% are used in the fermentation industry as a source of nitrogen for microorganisms and to adjust pH during fermentation. | https://en.wikipedia.org/wiki?curid=1365 |
22,507 | As early as in 1895, it was known that ammonia was "strongly antiseptic ... it requires 1.4 grams per litre to preserve beef tea (broth)." In one study, anhydrous ammonia destroyed 99.999% of zoonotic bacteria in 3 types of animal feed, but not silage. Anhydrous ammonia is currently used commercially to reduce or elimi... | https://en.wikipedia.org/wiki?curid=1365 |
22,508 | Lean finely textured beef (popularly known as "pink slime") in the beef industry is made from fatty beef trimmings (c. 50–70% fat) by removing the fat using heat and centrifugation, then treating it with ammonia to kill "E. coli". The process was deemed effective and safe by the US Department of Agriculture based on a ... | https://en.wikipedia.org/wiki?curid=1365 |
22,509 | The raw energy density of liquid ammonia is 11.5 MJ/L, which is about a third that of diesel. There is the opportunity to convert ammonia back to hydrogen, where it can be used to power hydrogen fuel cells, or it may be used directly within high-temperature solid oxide direct ammonia fuel cells to provide efficient pow... | https://en.wikipedia.org/wiki?curid=1365 |
22,510 | The conversion of ammonia to hydrogen via the sodium amide process, either for combustion or as fuel for a proton exchange membrane fuel cell, is possible. Another method is the catalytic decomposition of ammonia using solid catalysts. Conversion to hydrogen would allow the storage of hydrogen at nearly 18 wt% compared... | https://en.wikipedia.org/wiki?curid=1365 |
22,511 | Ammonia engines or ammonia motors, using ammonia as a working fluid, have been proposed and occasionally used. The principle is similar to that used in a fireless locomotive, but with ammonia as the working fluid, instead of steam or compressed air. Ammonia engines were used experimentally in the 19th century by Goldsw... | https://en.wikipedia.org/wiki?curid=1365 |
22,512 | Ammonia is sometimes proposed as a practical alternative to fossil fuel for internal combustion engines. | https://en.wikipedia.org/wiki?curid=1365 |
22,513 | Its high octane rating of 120 and low flame temperature allows the use of high compression ratios without a penalty of high production. Since ammonia contains no carbon, its combustion cannot produce carbon dioxide, carbon monoxide, hydrocarbons, or soot. | https://en.wikipedia.org/wiki?curid=1365 |
22,514 | Ammonia production currently creates 1.8% of global emissions. "Green ammonia" is ammonia produced by using green hydrogen (hydrogen produced by electrolysis), whereas "blue ammonia" is ammonia produced using blue hydrogen (hydrogen produced by steam methane reforming where the carbon dioxide has been captured and stor... | https://en.wikipedia.org/wiki?curid=1365 |
22,515 | However, ammonia cannot be easily used in existing Otto cycle engines because of its very narrow flammability range. The 60 MW Rjukan dam in Telemark, Norway, produced ammonia for many years from 1913, providing fertilizer for much of Europe. Despite this, several tests have been run. | https://en.wikipedia.org/wiki?curid=1365 |
22,516 | Compared to hydrogen as a fuel, ammonia is much more energy efficient, and could be produced, stored, and delivered at a much lower cost than hydrogen, which must be kept compressed or as a cryogenic liquid. | https://en.wikipedia.org/wiki?curid=1365 |
22,517 | Rocket engines have also been fueled by ammonia. The Reaction Motors XLR99 rocket engine that powered the hypersonic research aircraft used liquid ammonia. Although not as powerful as other fuels, it left no soot in the reusable rocket engine, and its density approximately matches the density of the oxidizer, liquid ox... | https://en.wikipedia.org/wiki?curid=1365 |
22,518 | In early August 2018, scientists from Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) announced the success of developing a process to release hydrogen from ammonia and harvest that at ultra-high purity as a fuel for cars. This uses a special membrane. Two demonstration fuel cell vehicl... | https://en.wikipedia.org/wiki?curid=1365 |
22,519 | In 2020, Saudi Arabia shipped 40 metric tons of liquid "blue ammonia" to Japan for use as a fuel. It was produced as a by-product by petrochemical industries, and can be burned without giving off greenhouse gases. Its energy density by volume is nearly double that of liquid hydrogen. If the process of creating it can b... | https://en.wikipedia.org/wiki?curid=1365 |
22,520 | Green ammonia is considered as a potential fuel for future container ships. In 2020, the companies DSME and MAN Energy Solutions announced the construction of an ammonia-based ship, DSME plans to commercialize it by 2025. The use of ammonia as a potential alternative fuel for aircraft jet engines is also being explored... | https://en.wikipedia.org/wiki?curid=1365 |
22,521 | Japan intends to implement a plan to develop ammonia co-firing technology that can increase the use of ammonia in power generation, as part of efforts to assist domestic and other Asian utilities to accelerate their transition to carbon neutrality. | https://en.wikipedia.org/wiki?curid=1365 |
22,522 | In June 2022, IHI Corporation succeeded in reducing greenhouse gases by over 99% during combustion of liquid ammonia in a 2,000-kilowatt-class gas turbine achieving truly CO₂-free power generation. | https://en.wikipedia.org/wiki?curid=1365 |
22,523 | In July 2022, Quad nations of Japan, the U.S., Australia and India agreed to promote technological development for clean-burning hydrogen and ammonia as fuels at the security grouping's first energy meeting. , however, significant amounts of NOx are produced. Nitrous oxide may also be a problem. | https://en.wikipedia.org/wiki?curid=1365 |
22,524 | Ammonia is used to scrub from the burning of fossil fuels, and the resulting product is converted to ammonium sulfate for use as fertilizer. Ammonia neutralises the nitrogen oxide () pollutants emitted by diesel engines. This technology, called SCR (selective catalytic reduction), relies on a vanadia-based catalyst. | https://en.wikipedia.org/wiki?curid=1365 |
22,525 | Due to its attributes, being liquid at ambient temperature under its own vapour pressure and having high volumetric and gravimetric energy density, ammonia is considered a suitable carrier for hydrogen, and may be cheaper than direct transport of liquid hydrogen. | https://en.wikipedia.org/wiki?curid=1365 |
22,526 | Because of ammonia's vaporization properties, it is a useful refrigerant. It was commonly used before the popularisation of chlorofluorocarbons (Freons). Anhydrous ammonia is widely used in industrial refrigeration applications and hockey rinks because of its high energy efficiency and low cost. It suffers from the dis... | https://en.wikipedia.org/wiki?curid=1365 |
22,527 | The potential importance of ammonia as a refrigerant has increased with the discovery that vented CFCs and HFCs are extremely potent and stable greenhouse gases. | https://en.wikipedia.org/wiki?curid=1365 |
22,528 | Ammonia, as the vapor released by smelling salts, has found significant use as a respiratory stimulant. Ammonia is commonly used in the illegal manufacture of methamphetamine through a Birch reduction. The Birch method of making methamphetamine is dangerous because the alkali metal and liquid ammonia are both extremely... | https://en.wikipedia.org/wiki?curid=1365 |
22,529 | Liquid ammonia is used for treatment of cotton materials, giving properties like mercerisation, using alkalis. In particular, it is used for prewashing of wool. | https://en.wikipedia.org/wiki?curid=1365 |
22,530 | At standard temperature and pressure, ammonia is less dense than atmosphere and has approximately 45–48% of the lifting power of hydrogen or helium. Ammonia has sometimes been used to fill balloons as a lifting gas. Because of its relatively high boiling point (compared to helium and hydrogen), ammonia could potentiall... | https://en.wikipedia.org/wiki?curid=1365 |
22,531 | Ammonia has been used to darken quartersawn white oak in Arts & Crafts and Mission-style furniture. Ammonia fumes react with the natural tannins in the wood and cause it to change colours. | https://en.wikipedia.org/wiki?curid=1365 |
22,532 | The U.S. Occupational Safety and Health Administration (OSHA) has set a 15-minute exposure limit for gaseous ammonia of 35 ppm by volume in the environmental air and an 8-hour exposure limit of 25 ppm by volume. The National Institute for Occupational Safety and Health (NIOSH) recently reduced the IDLH (Immediately Dan... | https://en.wikipedia.org/wiki?curid=1365 |
22,533 | Liquid ammonia is dangerous because it is hygroscopic and because it can cause caustic burns. See for more information. | https://en.wikipedia.org/wiki?curid=1365 |
22,534 | The toxicity of ammonia solutions does not usually cause problems for humans and other mammals, as a specific mechanism exists to prevent its build-up in the bloodstream. Ammonia is converted to carbamoyl phosphate by the enzyme carbamoyl phosphate synthetase, and then enters the urea cycle to be either incorporated in... | https://en.wikipedia.org/wiki?curid=1365 |
22,535 | Ammonia is present in coking wastewater streams, as a liquid by-product of the production of coke from coal. In some cases, the ammonia is discharged to the marine environment where it acts as a pollutant. The Whyalla steelworks in South Australia is one example of a coke-producing facility which discharges ammonia int... | https://en.wikipedia.org/wiki?curid=1365 |
22,536 | Ammonia toxicity is believed to be a cause of otherwise unexplained losses in fish hatcheries. Excess ammonia may accumulate and cause alteration of metabolism or increases in the body pH of the exposed organism. Tolerance varies among fish species. At lower concentrations, around 0.05 mg/L, un-ionised ammonia is harmf... | https://en.wikipedia.org/wiki?curid=1365 |
22,537 | During winter, when reduced feeds are administered to aquaculture stock, ammonia levels can be higher. Lower ambient temperatures reduce the rate of algal photosynthesis so less ammonia is removed by any algae present. Within an aquaculture environment, especially at large scale, there is no fast-acting remedy to eleva... | https://en.wikipedia.org/wiki?curid=1365 |
22,538 | Similar to propane, anhydrous ammonia boils below room temperature when at atmospheric pressure. A storage vessel capable of is suitable to contain the liquid. Ammonia is used in numerous different industrial application requiring carbon or stainless steel storage vessels. Ammonia with at least 0.2% by weight water con... | https://en.wikipedia.org/wiki?curid=1365 |
22,539 | The hazards of ammonia solutions depend on the concentration: "dilute" ammonia solutions are usually 5–10% by weight (<5.62 mol/L); "concentrated" solutions are usually prepared at >25% by weight. A 25% (by weight) solution has a density of 0.907 g/cm, and a solution that has a lower density will be more concentrated. ... | https://en.wikipedia.org/wiki?curid=1365 |
22,540 | The ammonia vapour from concentrated ammonia solutions is severely irritating to the eyes and the respiratory tract, and experts warn that these solutions only be handled in a fume hood. Saturated ("0.880" – see #Properties) solutions can develop a significant pressure inside a closed bottle in warm weather, and expert... | https://en.wikipedia.org/wiki?curid=1365 |
22,541 | Experts warn that ammonia solutions not be mixed with halogens, as toxic and/or explosive products are formed. Experts also warn that prolonged contact of ammonia solutions with silver, mercury or iodide salts can also lead to explosive products: such mixtures are often formed in qualitative inorganic analysis, and tha... | https://en.wikipedia.org/wiki?curid=1365 |
22,542 | Anhydrous ammonia is classified as toxic (T) and dangerous for the environment (N). The gas is flammable (autoignition temperature: 651 °C) and can form explosive mixtures with air (16–25%). The permissible exposure limit (PEL) in the United States is 50 ppm (35 mg/m), while the IDLH concentration is estimated at 300 p... | https://en.wikipedia.org/wiki?curid=1365 |
22,543 | Ammonia reacts violently with the halogens. Nitrogen triiodide, a primary high explosive, is formed when ammonia comes in contact with iodine. Ammonia causes the explosive polymerisation of ethylene oxide. It also forms explosive fulminating compounds with compounds of gold, silver, mercury, germanium or tellurium, and... | https://en.wikipedia.org/wiki?curid=1365 |
22,544 | Ammonia adsorption followed by FTIR as well as temperature programmed desorption of ammonia (NH3-TPD) are very valuable methods to characterize acid-base properties of heterogeneous catalysts. | https://en.wikipedia.org/wiki?curid=1365 |
22,545 | Ammonia is one of the most produced inorganic chemicals, with global production reported at 175 million tonnes in 2018. China accounted for 28.5% of that, followed by Russia at 10.3%, the United States at 9.1%, and India at 6.7%. | https://en.wikipedia.org/wiki?curid=1365 |
22,546 | Before the start of World War I, most ammonia was obtained by the dry distillation of nitrogenous vegetable and animal waste products, including camel dung, where it was distilled by the reduction of nitrous acid and nitrites with hydrogen; in addition, it was produced by the distillation of coal, and also by the decom... | https://en.wikipedia.org/wiki?curid=1365 |
22,547 | Mass production uses the Haber–Bosch process, a gas phase reaction between hydrogen () and nitrogen () at a moderately-elevated temperature (450 °C) and high pressure (): | https://en.wikipedia.org/wiki?curid=1365 |
22,548 | This reaction is exothermic and results in decreased entropy, meaning that the reaction is favoured at lower temperatures and higher pressures. It is difficult and expensive to achieve, as lower temperatures result in slower reaction kinetics (hence a slower reaction rate) and high pressure requires high-strength press... | https://en.wikipedia.org/wiki?curid=1365 |
22,549 | The choice of catalyst is important for synthesizing ammonia. In 2012, Hideo Hosono's group found that Ru-loaded calcium-aluminum oxide C12A7: electride works well as a catalyst and pursued more efficient formation. This method is implemented in a small plant for ammonia synthesis in Japan. In 2019, Hosono's group foun... | https://en.wikipedia.org/wiki?curid=1365 |
22,550 | Ammonia can be synthesized electrochemically. The only required inputs are sources of nitrogen (potentially atmospheric) and hydrogen (water), allowing generation at the point of use. The availability of renewable energy creates the possibility of zero emission production. | https://en.wikipedia.org/wiki?curid=1365 |
22,551 | Another electrochemical synthesis mode involves the reductive formation of lithium nitride, which can be protonated to ammonia, given a proton source. Ethanol has been used as such a source, although it may degrade. The first use of this chemistry was reported in 1930, where lithium solutions in ethanol were used to pr... | https://en.wikipedia.org/wiki?curid=1365 |
22,552 | In 2020, Lazouski et al. developed a solvent-agnostic gas diffusion electrode to improve nitrogen transport to the reactive lithium. The study observed production rates of up to 30 ± 5 nanomoles/s/cm and Faradaic efficiencies of up to 47.5 ± 4% at ambient temperature and 1 bar pressure. | https://en.wikipedia.org/wiki?curid=1365 |
22,553 | In 2021, Suryanto et al. replaced ethanol with a tetraalkyl phosphonium salt. This cation can stably undergo deprotonation–reprotonation cycles, while it enhances the medium's ionic conductivity. The study observed production rates of 53 ± 1 nanomoles/s/cm at 69 ± 1% faradaic efficiency experiments under 0.5-bar hydrog... | https://en.wikipedia.org/wiki?curid=1365 |
22,554 | Ammonia is both a metabolic waste and a metabolic input throughout the biosphere. It is an important source of nitrogen for living systems. Although atmospheric nitrogen abounds (more than 75%), few living creatures are capable of using atmospheric nitrogen in its diatomic form, gas. Therefore, nitrogen fixation is req... | https://en.wikipedia.org/wiki?curid=1365 |
22,555 | In humans, inhaling ammonia in high concentrations can be fatal. Exposure to ammonia can cause headaches, edema, impaired memory, seizures and coma as it is neurotoxic in nature. | https://en.wikipedia.org/wiki?curid=1365 |
22,556 | In certain organisms, ammonia is produced from atmospheric nitrogen by enzymes called nitrogenases. The overall process is called nitrogen fixation. Intense effort has been directed toward understanding the mechanism of biological nitrogen fixation. The scientific interest in this problem is motivated by the unusual st... | https://en.wikipedia.org/wiki?curid=1365 |
22,557 | Ammonia is also a metabolic product of amino acid deamination catalyzed by enzymes such as glutamate dehydrogenase 1. Ammonia excretion is common in aquatic animals. In humans, it is quickly converted to urea, which is much less toxic, particularly less basic. This urea is a major component of the dry weight of urine. ... | https://en.wikipedia.org/wiki?curid=1365 |
22,558 | Ammonia plays a role in both normal and abnormal animal physiology. It is biosynthesised through normal amino acid metabolism and is toxic in high concentrations. The liver converts ammonia to urea through a series of reactions known as the urea cycle. Liver dysfunction, such as that seen in cirrhosis, may lead to elev... | https://en.wikipedia.org/wiki?curid=1365 |
22,559 | Ammonia is important for normal animal acid/base balance. After formation of ammonium from glutamine, α-ketoglutarate may be degraded to produce two bicarbonate ions, which are then available as buffers for dietary acids. Ammonium is excreted in the urine, resulting in net acid loss. Ammonia may itself diffuse across t... | https://en.wikipedia.org/wiki?curid=1365 |
22,560 | Ammonium ions are a toxic waste product of metabolism in animals. In fish and aquatic invertebrates, it is excreted directly into the water. In mammals, sharks, and amphibians, it is converted in the urea cycle to urea, which is less toxic and can be stored more efficiently. In birds, reptiles, and terrestrial snails, ... | https://en.wikipedia.org/wiki?curid=1365 |
22,561 | Ammonia has been detected in the atmospheres of the giant planets, including Jupiter, along with other gases such as methane, hydrogen, and helium. The interior of Saturn may include frozen ammonia crystals. It is found on Deimos and Phobos – the two moons of Mars. | https://en.wikipedia.org/wiki?curid=1365 |
22,562 | Ammonia was first detected in interstellar space in 1968, based on microwave emissions from the direction of the galactic core. This was the first polyatomic molecule to be so detected. | https://en.wikipedia.org/wiki?curid=1365 |
22,563 | The sensitivity of the molecule to a broad range of excitations and the ease with which it can be observed in a number of regions has made ammonia one of the most important molecules for studies of molecular clouds. The relative intensity of the ammonia lines can be used to measure the temperature of the emitting mediu... | https://en.wikipedia.org/wiki?curid=1365 |
22,564 | The following isotopic species of ammonia have been detected: , , , , and . The detection of triply deuterated ammonia was considered a surprise as deuterium is relatively scarce. It is thought that the low-temperature conditions allow this molecule to survive and accumulate. | https://en.wikipedia.org/wiki?curid=1365 |
22,565 | Since its interstellar discovery, has proved to be an invaluable spectroscopic tool in the study of the interstellar medium. With a large number of transitions sensitive to a wide range of excitation conditions, has been widely astronomically detected – its detection has been reported in hundreds of journal articles. L... | https://en.wikipedia.org/wiki?curid=1365 |
22,566 | The study of interstellar ammonia has been important to a number of areas of research in the last few decades. Some of these are delineated below and primarily involve using ammonia as an interstellar thermometer. | https://en.wikipedia.org/wiki?curid=1365 |
22,567 | The interstellar abundance for ammonia has been measured for a variety of environments. The []/[] ratio has been estimated to range from 10 in small dark clouds up to 10 in the dense core of the Orion molecular cloud complex. Although a total of 18 total production routes have been proposed, the principal formation mec... | https://en.wikipedia.org/wiki?curid=1365 |
22,568 | The rate constant, "k", of this reaction depends on the temperature of the environment, with a value of 5.2×10 at 10 K. The rate constant was calculated from the formula . For the primary formation reaction, and . Assuming an abundance of 3×10 and an electron abundance of 10 typical of molecular clouds, the formation w... | https://en.wikipedia.org/wiki?curid=1365 |
22,569 | All other proposed formation reactions have rate constants of between 2 and 13 orders of magnitude smaller, making their contribution to the abundance of ammonia relatively insignificant. As an example of the minor contribution other formation reactions play, the reaction: | https://en.wikipedia.org/wiki?curid=1365 |
22,570 | has a rate constant of 2.2. Assuming densities of 10 and []/[] ratio of 10, this reaction proceeds at a rate of 2.2, more than 3 orders of magnitude slower than the primary reaction above. | https://en.wikipedia.org/wiki?curid=1365 |
22,571 | There are 113 total proposed reactions leading to the destruction of . Of these, 39 were tabulated in extensive tables of the chemistry among C, N, and O compounds. A review of interstellar ammonia cites the following reactions as the principal dissociation mechanisms: | https://en.wikipedia.org/wiki?curid=1365 |
22,572 | with rate constants of 4.39×10 and 2.2×10, respectively. The above equations (, ) run at a rate of 8.8×10 and 4.4×10, respectively. These calculations assumed the given rate constants and abundances of []/[] = 10, []/[] = 2×10, []/[] = 2×10, and total densities of "n" = 10, typical of cold, dense, molecular clouds. Cle... | https://en.wikipedia.org/wiki?curid=1365 |
22,573 | Radio observations of from the Effelsberg 100-m Radio Telescope reveal that the ammonia line is separated into two components – a background ridge and an unresolved core. The background corresponds well with the locations previously detected CO. The 25 m Chilbolton telescope in England detected radio signatures of ammo... | https://en.wikipedia.org/wiki?curid=1365 |
22,574 | Microwave radiation from ammonia was observed in several galactic objects including W3(OH), Orion A, W43, W51, and five sources in the galactic centre. The high detection rate indicates that this is a common molecule in the interstellar medium and that high-density regions are common in the galaxy. | https://en.wikipedia.org/wiki?curid=1365 |
22,575 | VLA observations of in seven regions with high-velocity gaseous outflows revealed condensations of less than 0.1 pc in L1551, S140, and Cepheus A. Three individual condensations were detected in Cepheus A, one of them with a highly elongated shape. They may play an important role in creating the bipolar outflow in the ... | https://en.wikipedia.org/wiki?curid=1365 |
22,576 | Extragalactic ammonia was imaged using the VLA in IC 342. The hot gas has temperatures above 70 K, which was inferred from ammonia line ratios and appears to be closely associated with the innermost portions of the nuclear bar seen in CO. was also monitored by VLA toward a sample of four galactic ultracompact HII regio... | https://en.wikipedia.org/wiki?curid=1365 |
22,577 | Absorption at 2.97 micrometres due to solid ammonia was recorded from interstellar grains in the Becklin-Neugebauer Object and probably in NGC 2264-IR as well. This detection helped explain the physical shape of previously poorly understood and related ice absorption lines. | https://en.wikipedia.org/wiki?curid=1365 |
22,578 | A spectrum of the disk of Jupiter was obtained from the Kuiper Airborne Observatory, covering the 100 to 300 cm spectral range. Analysis of the spectrum provides information on global mean properties of ammonia gas and an ammonia ice haze. | https://en.wikipedia.org/wiki?curid=1365 |
22,579 | A total of 149 dark cloud positions were surveyed for evidence of 'dense cores' by using the (J,K) = (1,1) rotating inversion line of NH. In general, the cores are not spherically shaped, with aspect ratios ranging from 1.1 to 4.4. It is also found that cores with stars have broader lines than cores without stars. | https://en.wikipedia.org/wiki?curid=1365 |
22,580 | Ammonia has been detected in the Draco Nebula and in one or possibly two molecular clouds, which are associated with the high-latitude galactic infrared cirrus. The finding is significant because they may represent the birthplaces for the Population I metallicity B-type stars in the galactic halo that could have been b... | https://en.wikipedia.org/wiki?curid=1365 |
22,581 | By balancing and stimulated emission with spontaneous emission, it is possible to construct a relation between excitation temperature and density. Moreover, since the transitional levels of ammonia can be approximated by a 2-level system at low temperatures, this calculation is fairly simple. This premise can be applie... | https://en.wikipedia.org/wiki?curid=1365 |
22,582 | Ultra-compact HII regions are among the best tracers of high-mass star formation. The dense material surrounding UCHII regions is likely primarily molecular. Since a complete study of massive star formation necessarily involves the cloud from which the star formed, ammonia is an invaluable tool in understanding this su... | https://en.wikipedia.org/wiki?curid=1365 |
22,583 | Ammonia has been detected in external galaxies, and by simultaneously measuring several lines, it is possible to directly measure the gas temperature in these galaxies. Line ratios imply that gas temperatures are warm (≈50 K), originating from dense clouds with sizes of tens of pc. This picture is consistent with the p... | https://en.wikipedia.org/wiki?curid=1365 |
22,584 | The Boeing CH-47 Chinook is a tandem rotor helicopter developed by American rotorcraft company Vertol and manufactured by Boeing Vertol. The Chinook is a heavy-lift helicopter that is among the heaviest lifting Western helicopters. Its name, Chinook, is from the Native American Chinook people of Oregon and Washington s... | https://en.wikipedia.org/wiki?curid=38005 |
22,585 | The Chinook was originally designed by Vertol, which had begun work in 1957 on a new tandem-rotor helicopter, designated as the Vertol Model 107 or V-107. Around the same time, the United States Department of the Army announced its intention to replace the piston engine–powered Sikorsky CH-37 Mojave with a new, gas tur... | https://en.wikipedia.org/wiki?curid=38005 |
22,586 | The Chinook possesses several means of loading various cargoes, including multiple doors across the fuselage, a wide loading ramp located at the rear of the fuselage and a total of three external ventral cargo hooks to carry underslung loads. Capable of a top speed of , upon its introduction to service in 1962, the hel... | https://en.wikipedia.org/wiki?curid=38005 |
22,587 | The military version of the helicopter has been exported to nations across the world; the U.S. Army and the Royal Air Force (see Boeing Chinook (UK variants)) have been its two largest users. The civilian version of the Chinook is the Boeing Vertol 234. It has been used by civil operators not only for passenger and car... | https://en.wikipedia.org/wiki?curid=38005 |
22,588 | During late 1956, the United States Department of the Army announced its intention to replace the Sikorsky CH-37 Mojave, which was powered by piston engines, with a new, gas turbine-powered helicopter. Turbine engines were also a key design feature of the smaller UH-1 "Huey" utility helicopter. Following a design compe... | https://en.wikipedia.org/wiki?curid=38005 |
22,589 | During 1957, Vertol commenced work upon a new tandem-rotor helicopter, designated as the Vertol Model 107 or V-107. During June 1958, the U.S. Army awarded a contract to Vertol for the acquisition of a small number of the rotorcraft, giving it the "YHC-1A" designation. As ordered, the YHC-1A possessed the capacity to c... | https://en.wikipedia.org/wiki?curid=38005 |
22,590 | The CH-47 is powered by two Lycoming T55 turboshaft engines, mounted on each side of the helicopter's rear pylon and connected to the rotors by drive shafts. Initial models were fitted with engines rated at each. The counter-rotating rotors eliminate the need for an antitorque vertical rotor, allowing all power to be u... | https://en.wikipedia.org/wiki?curid=38005 |
22,591 | Improved and more powerful versions of the CH-47 have been developed since the helicopter entered service. The U.S. Army's first major design leap was the now-common CH-47D, which entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilo... | https://en.wikipedia.org/wiki?curid=38005 |
22,592 | A commercial model of the Chinook, the Boeing-Vertol Model 234, is used worldwide for logging, construction, fighting forest fires, and supporting petroleum extraction operations. In December 2006, Columbia Helicopters Inc purchased the type certificate of the Model 234 from Boeing. The Chinook has also been licensed t... | https://en.wikipedia.org/wiki?curid=38005 |
22,593 | The Army finally settled on the larger Chinook as its standard medium-transport helicopter, and as of February 1966, 161 aircraft had been delivered to the Army. The 1st Cavalry Division had brought its organic Chinook battalion (three Chinook companies) when it arrived in 1965 and a separate aviation medium helicopter... | https://en.wikipedia.org/wiki?curid=38005 |
22,594 | The most spectacular mission in Vietnam for the Chinook was the placing of artillery batteries in perilous mountain positions inaccessible by any other means, and then keeping them resupplied with large quantities of ammunition. The 1st Cavalry Division found that its CH-47s were limited to a payload when operating in ... | https://en.wikipedia.org/wiki?curid=38005 |
22,595 | As with any new piece of equipment, the Chinook presented a major problem of "customer education". Commanders and crew chiefs had to be constantly alert that eager soldiers did not overload the temptingly large cargo compartment. It would be some time before troops would be experts at using sling loads. The Chinook soo... | https://en.wikipedia.org/wiki?curid=38005 |
22,596 | At the Vietnam war's peak the US Army had 21 Chinook companies in Vietnam. Pilots discovered the CH-47A's transmission system could not handle the two gas turbines running at full power, and high humidity and heat reduced the maximum lift by more than 20% in the low lands and 30% in mountain areas. More powerful, impro... | https://en.wikipedia.org/wiki?curid=38005 |
22,597 | Four CH-47s were converted into ACH-47As by adding armor and improved engines. Its armament included two fixed forward firing M24A1 20mm cannons, one turret with 40 mm automatic grenade launcher on the nose, five .50 in machine guns and two weapon pods on the sides that could carry either XM159B/XM159C 70 mm rocket lau... | https://en.wikipedia.org/wiki?curid=38005 |
22,598 | During the 1970s, the United States and Iran had a strong relationship, in which the Iranian armed forces began to use many American military aircraft, most notably the F-14 Tomcat, as part of a modernization program. After an agreement signed between Boeing and Agusta, the Imperial Iranian Air Force purchased 20 Agust... | https://en.wikipedia.org/wiki?curid=38005 |
22,599 | In the 1978 Iranian Chinook shootdown, four Iranian CH-47Cs penetrated into Soviet airspace in the Turkmenistan Military District. They were intercepted by a MiG-23M which shot down one, killing eight crew members, and forced a second one to land. Chinook helicopters were used in efforts by the Imperial Iranian loyalis... | https://en.wikipedia.org/wiki?curid=38005 |
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