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Ethanimine
Ethanimine is an organonitrogen compound classified as an imine. It is formed by reacting acetaldehyde and ammonia, but rapidly polymerizes to acetaldehyde ammonia trimer. It has two tautomers: ethanimine, an imine, and ethenamine or aminoethylene, an amine. Ethanimine has two hydrogens on the carbon, while ethenamine has two on the nitrogen atom. Occurrence It is not well known terrestrially, but has been detected in abundance toward Sagittarius B2 (Sgr B2), a dense interstellar cloud between stars toward the galactic center of the Milky Way. The distance between the Sgr B2 cloud and center of galaxy is 100 pc (1 pc = 3.26 ly). Ethanimine is mainly found in hot cores of ISM clouds; in case of Sgr B2, the region would be the Sgr B2 N and Sgr B2 M. Radio telescopes such as the Green Bank Observatory's Green Bank Telescope The Robert C. Byrd Green Bank Telescope (GBT) in Green Bank, West Virginia, US is the world's largest fully steerable radio telescope, surpassing the Effelsb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-Methylmethanimine
''N''-Methylmethanimine or ''N''‐methyl methylenimine is a reactive molecular substance containing a methyl group attached to an imine. It can be written as CH3N=CH2. On a timescale of minutes it self reacts to form a trimer, of trimethyl 1,3,5-triazinane. ''N''-Methylmethanimine is formed naturally in the Earth's atmosphere, by oxidation of dimethylamine and trimethylamine, both of which are produced by animals, or burning. Production ''N''-Methylmethanimine can be produced in two steps from dimethylamine, by first chlorinating the nitrogen atom with solid N-chlorosuccinimide, and then treating with potassium ''tert''-butoxide at 90°C. Also it can be formed directly by thermal decomposition. It can also be prepared from the trimer: 1,3,5-trimethyl-1,3,5-triazinane by heating to . At , trimethylamine decomposes into methane and ''N''-methylmethanimine. Natural occurrence ''N''-Methylmethanimine should be formed in the atmosphere as a result of degradation by oxidation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanimine
Methylene imine is an organic compound with the formula . The simplest imine, it is a stable, colorless gas that has been detected throughout the universe. Structural parameters determined by microwave spectroscopy include a C=N bond length of 1.27 Å, an N–H bond length of 1.02 Å and an HNC bond angle of 110.5°. Because unhindered imines polymerize or oligomer In chemistry and biochemistry, an oligomer () is a molecule that consists of a few repeating units which could be derived, actually or conceptually, from smaller molecules, monomers.Quote: ''Oligomer molecule: A molecule of intermediate relativ ...ize when concentrated, methylene imine has not been isolated as a liquid or bulk solid. Attempted synthesis of methylene imine from the reaction of ammonia and formaldehyde produces hexamethylenetetramine.{{cite encyclopedia , title=Amines, Aliphatic , encyclopedia=Ullmann's Encyclopedia of Industrial Chemistry , publisher=Wiley-VCH Verlag GmbH , year=2000 , isbn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imine
In organic chemistry, an imine ( or ) is a functional group or organic compound containing a carbon–nitrogen double bond (). The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bonds. Imines are common in synthetic and naturally occurring compounds and they participate in many reactions. Structure For ketimines and aldimines, respectively, the five core atoms (C2C=NX and C(H)C=NX, X = H or C) are coplanar. Planarity results from the sp2-hybridization of the mutually double-bonded carbon and the nitrogen atoms. The C=N distance is 1.29-1.31 Å for nonconjugated imines and 1.35 Å for conjugated imines. By contrast, C-N distances in amines and nitriles are 1.47 and 1.16 Å, respectively. Rotation about the C=N bond is slow. Using NMR spectroscopy, both E- and Z-isomers of aldimines have been detected. Owing to steric effects, the E isomer is favored. Nomenclature and classification The term "imine" was coine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetaldehyde Ammonia Trimer
Acetaldehyde ammonia trimer is a chemical compound described by the formula (CH3CHNH)3. The pure material is colourless but samples often appear light yellow or slightly beige due to the degradation by oxidation. It is hygroscopic, and can be found in a trihydrate form. As implied by its name, it is a trimeric species formed from the reaction of acetaldehyde and ammonia: : 3 CH3CHO + 3 NH3 → (CH3CHNH)3 + 3 H2O Studies using NMR spectroscopy indicate that the three methyl groups are equatorial, thus the molecule has C3v point group symmetry. The compound is related to hexamethylenetetramine, which is the condensation product of ammonia and formaldehyde Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section F .... References {{reflist External linksMaterial safety data sheet Ni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tautomer
Tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hydrogen atom within the compound. The phenomenon of tautomerization is called tautomerism, also called desmotropism. Tautomerism is for example relevant to the behavior of amino acids and nucleic acids, two of the fundamental building blocks of life. Care should be taken not to confuse tautomers with depictions of "contributing structures" in chemical resonance. Tautomers are distinct chemical species that can be distinguished by their differing atomic connectivities, molecular geometries, and physicochemical and spectroscopic properties, whereas resonance forms are merely alternative Lewis structure (valence bond theory) depictions of a single chemical species, whose true structure is best described as the "average" of the idealized, hypothe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amine
In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines). Important amines include amino acids, biogenic amines, trimethylamine, and aniline; Inorganic derivatives of ammonia are also called amines, such as monochloramine (). The substituent is called an amino group. Compounds with a nitrogen atom attached to a carbonyl group, thus having the structure , are called amides and have different chemical properties from amines. Classification of amines Amines can be classified according to the nature and number of substituents on nitrogen. Aliphatic amines contain only H and alkyl substituents. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagittarius B2
Sagittarius B2 (Sgr B2) is a giant molecular cloud of gas and dust that is located about from the center of the Milky Way. This complex is the largest molecular cloud in the vicinity of the core and one of the largest in the galaxy, spanning a region about across. The total mass of Sgr B2 is about 3 million times the mass of the Sun. The mean hydrogen density within the cloud is 3000 atoms per cm3, which is about 20–40 times denser than a typical molecular cloud. The internal structure of this cloud is complex, with varying densities and temperatures. The cloud is divided into three main cores, designated north (N), middle or main (M) and south (S) respectively. Thus Sgr B2(N) represents the north core. The sites Sgr B2(M) and Sgr B2(N) are sites of prolific star formation. The first 10 H II regions discovered were designated A through J. H II regions A–G, I and J lie within Sgr B2(M), while region K is in Sgr B2(N) and region H is in Sgr B2(S). The 5-parsec-wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milky Way
The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. The term ''Milky Way'' is a translation of the Latin ', from the Greek ('), meaning "milky circle". From Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies. The Milky Way is a barred spiral galaxy with an estimated D25 isophotal diameter of , but only about 1,000 light years thick at the spiral arms (more at the bulg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Bank Observatory
The Green Bank Observatory (previously National Radio Astronomy Observatory, Green Bank) is an astronomical observatory located in the National Radio Quiet Zone in Green Bank, West Virginia, U.S. It is the operator of the Robert C. Byrd Green Bank Telescope, the world's largest fully steerable radio telescope. The observatory was established as the National Science Foundation's (NSF) National Radio Astronomy Observatory (NRAO) in 1956 and made its first observations in 1958. It served as the NRAO's headquarters until 1966, after which the facility was known as the National Radio Astronomy Observatory, Green Bank. In October 2016, the observatory became an independent institution following a 2012 recommendation that the NSF fully divest itself from the facility by October 1, 2016. Green Bank Observatory subsequently retained partial NSF funding, established private contracts, and formed a partnership with West Virginia University. It is operated by the nonprofit Associated Univ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Bank Telescope
The Robert C. Byrd Green Bank Telescope (GBT) in Green Bank, West Virginia, US is the world's largest fully steerable radio telescope, surpassing the Effelsberg 100-m Radio Telescope in Germany. The Green Bank site was part of the National Radio Astronomy Observatory (NRAO) until September 30, 2016. Since October 1, 2016, the telescope has been operated by the independent Green Bank Observatory. The telescope's name honors the late Senator Robert C. Byrd who represented West Virginia and who pushed the funding of the telescope through Congress. The Green Bank Telescope operates at meter to millimeter wavelengths. Its 100-meter diameter collecting area, unblocked aperture, and good surface accuracy provide superb sensitivity across the telescope's full 0.1–116 GHz operating range. The GBT is fully steerable, and 85 percent of the local celestial hemisphere is accessible. It is used for astronomy about 6500 hours every year, with 2000–3000 hours per year going to high-fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Radio Astronomy Observatory
The National Radio Astronomy Observatory (NRAO) is a federally funded research and development center of the United States National Science Foundation operated under cooperative agreement by Associated Universities, Inc. for the purpose of radio astronomy. NRAO designs, builds, and operates its own high-sensitivity radio telescopes for use by scientists around the world. Locations Charlottesville, Virginia The NRAO headquarters is located on the campus of the University of Virginia in Charlottesville, Virginia. The North American ALMA Science Center and the NRAO Technology Center and Central Development Laboratory are also in Charlottesville. Green Bank, West Virginia NRAO was, until October 2016, the operator of the world's largest fully steerable radio telescope, the Robert C. Byrd Green Bank Telescope, which stands near Green Bank, West Virginia. The observatory contains several other telescopes, among them the telescope that utilizes an equatorial mount uncommon for radio te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
