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Triethylborane
Triethylborane (TEB), also called triethylboron, is an organoborane (a compound with a B–C bond). It is a colorless pyrophoric liquid. Its chemical formula is or , abbreviated . It is soluble in organic solvents tetrahydrofuran and hexane. Preparation and structure Triethylborane is prepared by the reaction of trimethyl borate with triethylaluminium: :Et3Al + (MeO)3B → Et3B + (MeO)3Al The molecule is monomeric, unlike H3B and Et3Al, which tend to dimerize. It has a planar BC3 core. Applications Turbojet engines Triethylborane was used to ignite the JP-7 fuel in the Pratt & Whitney J58 turbojet/ ramjet engines powering the Lockheed SR-71 Blackbird and its predecessor, the A-12 OXCART. Triethylborane is suitable because it ignites readily upon exposure to oxygen. It was chosen as an ignition method for reliability reasons, and in the case of the Blackbird, because JP-7 fuel has very low volatility and is difficult to ignite. Conventional ignition plugs posed a high r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falcon 9
Falcon 9 is a Reusable launch system#Partial reusable launch systems, partially reusable, two-stage-to-orbit, medium-lift launch vehicle designed and manufactured in the United States by SpaceX. The first Falcon 9 launch was on June 4, 2010, and the first commercial resupply mission to the International Space Station (ISS) launched on October 8, 2012. In 2020, it became the first commercial rocket to launch humans to orbit. The Falcon 9 has been noted for its reliability and high launch cadence, with successful launches, two in-flight failures, one partial failure and one pre-flight destruction. It is the most-launched American orbital rocket in history. The rocket has two-stage-to-orbit, two stages. The first (booster) stage carries the second stage and payload to a predetermined speed and altitude, after which the second stage accelerates the payload to its target orbit. The Booster (rocketry), booster is capable of Vertical takeoff, vertical landing, landing vertically to fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triethylaluminium
Triethylaluminium is one of the simplest examples of an organoaluminium compound. Despite its name the compound has the formula Al2( C2H5)6 (abbreviated as Al2Et6 or TEA). This colorless liquid is pyrophoric. It is an industrially important compound, closely related to trimethylaluminium. Structure and bonding The structure and bonding in Al2R6 and diborane are analogous (R = alkyl). Referring to Al2Me6, the Al-C(terminal) and Al-C(bridging) distances are 1.97 and 2.14 Å, respectively. The Al center is tetrahedral. The carbon atoms of the bridging ethyl groups are each surrounded by five neighbors: carbon, two hydrogen atoms and two aluminium atoms. The ethyl groups interchange readily intramolecularly. At higher temperatures, the dimer cracks into monomeric AlEt3. Synthesis and reactions Triethylaluminium can be formed via several routes. The discovery of an efficient route was a significant technological achievement. The multistep process uses aluminium, hydrogen gas, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lockheed SR-71 Blackbird
The Lockheed SR-71 "Blackbird" is a retired long-range, high-altitude, Mach 3+ strategic reconnaissance aircraft developed and manufactured by the American aerospace company Lockheed Corporation. Its nicknames include " Blackbird" and " Habu". The SR-71 was developed in the 1960s as a black project by Lockheed's Skunk Works division. American aerospace engineer Clarence "Kelly" Johnson was responsible for many of the SR-71's innovative concepts. Its shape was based on the Lockheed A-12, a pioneer in stealth technology with its reduced radar cross section, but the SR-71 was longer and heavier to carry more fuel and a crew of two in tandem cockpits. The SR-71 was revealed to the public in July 1964 and entered service in the United States Air Force (USAF) in January 1966. During missions, the SR-71 operated at high speeds and altitudes (Mach 3.2 at ), allowing it to evade or outrace threats. If a surface-to-air missile launch was detected, the standard evasive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethylborane
Trimethylborane (TMB) is a toxic, pyrophoric gas with the formula B(CH3)3 (which can also be written as Me3B, with Me representing methyl). Properties As a liquid it is colourless. The strongest line in the infrared spectrum is at 1330 cm−1 followed by lines at 3010 cm−1 and 1185 cm−1. Its melting point is −161.5 °C, and its boiling point is −20.2 °C. Vapour pressure is given by , where ''T'' is temperature in kelvins. Molecular weight is 55.914. The heat of vapourisation is 25.6 kJ/mol. Preparation Trimethylborane was first described in 1862 by Edward Frankland, who also mentioned its adduct with ammonia. Due to its dangerous nature the compound was no longer studied until 1921, when Alfred Stock and Friedrich Zeidler took advantage of the reaction between boron trichloride gas and dimethylzinc. Although the substance can be prepared using Grignard reagents the output is contaminated by unwanted products from the solvent. Trimet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organoborane
Organoboron chemistry or organoborane chemistry studies organoboron compounds, also called organoboranes. These chemical compounds combine boron and carbon; typically, they are organic derivatives of borane (BH3), as in the trialkyl boranes. Organoboranes and -borates enable many chemical transformations in organic chemistry — most importantly, hydroboration and carboboration. Most reactions transfer a nucleophilic boron substituent to an electrophilic center either inter- or intramolecularly. In particular, α,β-unsaturated borates and borates with an α leaving group are highly susceptible to intramolecular 1,2-migration of a group from boron to the electrophilic α position. Oxidation or protonolysis of the resulting organoboranes generates many organic products, including alcohols, carbonyl compounds, alkenes, and halides. Properties of the B-C bond The C-B bond has low polarity (electronegativity 2.55 for carbon and 2.04 for boron). Alkyl boron compounds are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrophoricity
A substance is pyrophoric (from , , 'fire-bearing') if it ignites spontaneously in air at or below (for gases) or within 5 minutes after coming into contact with air (for liquids and solids). Examples are organolithium compounds and triethylborane. Pyrophoric materials are often water-reactive as well and will ignite when they contact water or humid air. They can be handled safely in atmospheres of argon or (with a few exceptions) nitrogen. Fire classification fire extinguishers are designated for use in fires involving metals but not pyrophoric materials in general. A related concept is hypergolicity, in which two compounds spontaneously ignite when mixed. Uses The creation of sparks from metals is based on the pyrophoricity of small metal particles, and pyrophoric alloys are made for this purpose. Practical applications include the sparking mechanisms in lighters and various toys, using ferrocerium; starting fires without matches, using a firesteel; the flintlock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JP-7
Turbine Fuel Low Volatility JP-7, commonly known as JP-7 (referred to as Jet Propellant 7 prior to MIL-DTL-38219) is a specialized type of jet fuel developed at Pratt and Whitney by master chemist Clarence Brown CB Eichman in 1955 for the Central Intelligence Agency (CIA) for use in its reconnaissance aircraft, the Lockheed A-12, and subsequently for aircraft with similar high speed performance, the Lockheed YF-12 and Lockheed SR-71. It was also used for the higher speed Boeing X-51 Waverider. Usage JP-7 was developed for the Pratt & Whitney J58 (JT11D-20) turbojet engine, which was used primarily in the Lockheed SR-71 Blackbird which retired in 1999. The SR-71 design speed was Mach 3.2 at which very high skin temperatures occurred due to aerodynamic heating. A new jet fuel with a high flash point and high thermal stability was developed as the fuel had to be used as a heat sink for the severe high temperature environment in the aircraft. The Boeing X-51 Waverider also u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-1 (rocket Engine)
The F-1 is a rocket engine developed by Rocketdyne. The engine uses a gas-generator cycle developed in the United States in the late 1950s and was used in the Saturn V rocket in the 1960s and early 1970s. Five F-1 engines were used in the S-IC first stage of each Saturn V, which served as the main launch vehicle of the Apollo program. The F-1 remains the most powerful single combustion chamber liquid-propellant rocket engine ever developed. History Rocketdyne developed the F-1 and the E-1 to meet a 1955 U.S. Air Force requirement for a very large rocket engine. The E-1, although successfully tested in static firing, was quickly seen as a technological dead-end, and was abandoned for the larger, more powerful F-1. The Air Force eventually halted development of the F-1 because of a lack of requirement for such a large engine. However, the recently created National Aeronautics and Space Administration (NASA) appreciated the usefulness of an engine with so much power and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturn V
The Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, had multistage rocket, three stages, and was powered by liquid-propellant rocket, liquid fuel. Flown from 1967 to 1973, it was used for nine crewed flights to the Moon, and to launch Skylab, the first American space station. the Saturn V remains the only launch vehicle to have carried humans beyond low Earth orbit (LEO). The Saturn V holds the record for the largest payload capacity to low Earth orbit, , which included unburned propellant needed to send the Apollo command and service module and Apollo Lunar Module, Lunar Module to the Moon. The largest production model of the Saturn (rocket family), Saturn family of rockets, the Saturn V was designed under the direction of Wernher von Braun at the Marshall Space Flight Center in Huntsville, Alabama; the lead contractors for construction of the rocket were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SpaceX Merlin
Merlin is a family of rocket engines developed by SpaceX. They are currently a part of the Falcon 9 and Falcon Heavy launch vehicles, and were formerly used on the Falcon 1. Merlin engines use RP-1 and liquid oxygen as rocket propellants in a gas-generator power cycle. The Merlin engine was originally designed for sea recovery and reuse, but since 2016 the entire Falcon 9 booster is recovered for reuse by landing vertically on a landing pad using one of its nine Merlin engines. The injector at the heart of Merlin is of the pintle type that was first used in the Apollo Lunar Module landing engine ( LMDE). Propellants are fed by a single-shaft, dual- impeller turbopump. The turbopump also provides high-pressure fluid for the hydraulic actuators, which then recycles into the low-pressure inlet. This eliminates the need for a separate hydraulic drive system and means that thrust vectoring control failure by running out of hydraulic fluid is not possible. Revisions Merlin 1A The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraethyllead
Tetraethyllead (commonly styled tetraethyl lead), abbreviated TEL, is an organolead compound with the formula lead, Pb(ethyl group, C2H5)4. It was widely used as a fuel additive for much of the 20th century, first being mixed with gasoline beginning in the 1920s. This "leaded gasoline" had an increased octane rating that allowed Compression ratio, engine compression to be raised substantially and in turn increased vehicle performance and fuel economy. TEL was first chemical synthesis, synthesized by German chemist Carl Jacob Löwig in 1853. American chemical engineer Thomas Midgley Jr., who was working for the U.S. corporation General Motors, was the first to discover its effectiveness as an Antiknock agent, knock inhibitor on December 9th, 1921, after spending six years attempting to find an antiknock agent, additive that was both highly effective and inexpensive. Of the some 33,000 substances in total screened, lead was found to be the most effective antiknock agent, in that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
