|
Tetralin
Tetralin (1,2,3,4-tetrahydronaphthalene) is a hydrocarbon having the chemical formula C10H12. It is a partially hydrogenated derivative of naphthalene. It is a colorless liquid that is used as a hydrogen-donor solvent. Production Tetralin is produced by the catalytic hydrogenation of naphthalene. Although nickel catalysts are traditionally employed, many variations have been evaluated. Over-hydrogenation converts tetralin into decahydronaphthalene ( decalin). Rarely encountered is dihydronaphthalene ( dialin). Laboratory methods In a classic named reaction called the Darzens tetralin synthesis, named for Auguste Georges Darzens (1926), derivatives can be prepared by intramolecular electrophilic aromatic substitution reaction of a 1-aryl-pent-4-ene using concentrated sulfuric acid, Uses Tetralin is used as a hydrogen-donor solvent, for example in coal liquifaction. It functions as a source of H2, which is transferred to the coal. The partially hydrogenated coal is m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Reactor Experiment
The Sodium Reactor Experiment was a pioneering nuclear power plant built by Atomics International at the Santa Susana Field Laboratory near Simi Valley, California, Simi Valley, California. The reactor operated from 1957 to 1964. On July 12, 1957 the Sodium Reactor Experiment became the first nuclear reactor in California to produce electrical power for a commercial power grid by powering the nearby city of Moorpark. In July 1959, the reactor experienced a partial Nuclear meltdown, meltdown when 13 of the reactor's 43 fuel elements partially melted, and radioactive gas was released into the atmosphere. The reactor was repaired and restarted in September 1960. In February 1964, the Sodium Reactor Experiment was in operation for the last time. Removal of the deactivated reactor was completed in 1981. Technical analyses of the 1959 incident have produced contrasting conclusions regarding the types and quantities of radioactive materials released. Members of the neighboring communities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetralin Synthesis 01
Tetralin (1,2,3,4-tetrahydronaphthalene) is a hydrocarbon having the chemical formula C10H12. It is a partially hydrogenated derivative of naphthalene. It is a colorless liquid that is used as a hydrogen-donor solvent. Production Tetralin is produced by the catalytic hydrogenation of naphthalene. Although nickel catalysts are traditionally employed, many variations have been evaluated. Over-hydrogenation converts tetralin into decahydronaphthalene (decalin). Rarely encountered is dihydronaphthalene (dialin). Laboratory methods In a classic named reaction called the Darzens tetralin synthesis, named for Auguste Georges Darzens (1926), derivatives can be prepared by intramolecular electrophilic aromatic substitution reaction of a 1-aryl-pent-4-ene using concentrated sulfuric acid, Uses Tetralin is used as a hydrogen-donor solvent, for example in coal liquifaction. It functions as a source of H2, which is transferred to the coal. The partially hydrogenated coal is more sol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naphthalene
Naphthalene is an organic compound with formula . It is the simplest polycyclic aromatic hydrocarbon, and is a white Crystal, crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 Parts-per notation, ppm by mass. As an Aromaticity, aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. It is the main ingredient of traditional mothballs. History In the early 1820s, two separate reports described a white solid with a pungent odor derived from the distillation of coal tar. In 1821, John Kidd (chemist), John Kidd cited these two disclosures and then described many of this substance's properties and the means of its production. He proposed the name ''naphthaline'', as it had been derived from a kind of naphtha (a broad term encompassing any volatile, flammable liquid hydrocarbon mixture, including coal tar). Naphthalene's chemical formula was determined by Michael Faraday in 1826. The structure of two f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Bromide
Hydrogen bromide is the inorganic compound with the formula . It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room temperature. Aqueous solutions that are 47.6% HBr by mass form a constant-boiling azeotrope mixture that boils at . Boiling less concentrated solutions releases H2O until the constant-boiling mixture composition is reached. Hydrogen bromide, and its aqueous solution, hydrobromic acid, are commonly used reagents in the preparation of bromide compounds. Reactions Organic chemistry Hydrogen bromide and hydrobromic acid are important reagents in the production of organobromine compounds.Greenwood, N. N.; Earnshaw, A. Chemistry of the Elements; Butterworth-Heineman: Oxford, Great Britain; 1997; pp. 809–812.Vollhardt, K. P. C.; Neil E. Schore, Schore, N. E. Organic Chemistry: Structure and Function; 4th Ed.; W. H. Freeman and Company: New York, N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auguste Georges Darzens
Auguste Georges Darzens (12 July 1867 in Moscow, Russia – 10 September 1954) was a Russia, Russian-born French people, French organic chemist. Biography From 1886 he studied at the École Polytechnique in Paris under Édouard Grimaux, Louis Édouard Grimaux. In 1895 he received his agrégation in physics and in 1899 his medical doctorate. From 1913 to 1937, he was a professor of chemistry at the École Polytechnique. In the meantime, from 1897 to 1920, he served as director of a research laboratory at LT Piver, a perfumery outfit. In 1904, he discovered the Darzens reaction, a chemical reaction also known as the Darzens condensation and Darzens glycidic ester condensation.Darzens, G., Compt. Rend. 1904, 139, 1214 Other reactions named after him include the Darzens tetralin synthesis, Darzens halogenation and the Darzens synthesis of unsaturated ketones. His book, "''Initiation chimique''" (1909), was translated into English in 1913 and published with the title of "Chemistr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poise (unit)
The poise (symbol P; ) is the unit of dynamic viscosity (absolute viscosity) in the centimetre–gram–second system of units (CGS). It is named after Jean Léonard Marie Poiseuille (see Hagen–Poiseuille equation). The centipoise (1 cP = 0.01 P) is more commonly used than the poise itself. Dynamic viscosity has dimensions of \mathrm, that is, [\mathsf^1 \mathsf^ \mathsf^]. 1~\text = 0.1~\text^ \text \text^ = 1~\text^ \text \text^ = 1~\text \text \text^. The analogous unit in the SI, International System of Units is the pascal-second (Pa⋅s): 1~\text \text = 1~\text \text \text^ = 1~\text^ \text \text^ = 10~\text. The poise is often used with the metric prefix ''centi-'' because the viscosity of water at 20 °C (standard conditions for temperature and pressure) is almost exactly 1 centipoise. A centipoise is one hundredth of a poise, or one millipascal-second (mPa⋅s) in SI units (1 cP = 10−3 Pa⋅s = 1 mPa⋅s). The CGS symbol fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, and hydrogen, with the molecular formula . It is a colorless, odorless, and Viscosity, viscous liquid that is Miscibility, miscible with water. Pure sulfuric acid does not occur naturally due to its Dehydration reaction, strong affinity to water vapor; it is Hygroscopy, hygroscopic and readily absorbs water vapor from the Atmosphere of Earth, air. Concentrated sulfuric acid is a strong oxidant with powerful dehydrating properties, making it highly corrosive towards other materials, from rocks to metals. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid but, to the contrary, dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is releas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methemoglobinemia
Methemoglobinemia, or methaemoglobinaemia, is a condition of elevated methemoglobin in the blood. Symptoms may include headache, dizziness, shortness of breath, nausea, poor muscle coordination, and blue-colored skin (cyanosis). Complications may include seizures and heart arrhythmias. Methemoglobinemia can be due to certain medications, chemicals, or food or it can be inherited. Substances involved may include benzocaine, nitrites, or dapsone. The underlying mechanism involves some of the iron in hemoglobin being converted from the ferrous [Fe2+] to the ferric [Fe3+] form. The diagnosis is often suspected based on symptoms and a Hypoxia (medical), low blood oxygen that does not improve with oxygen therapy. Diagnosis is confirmed by a blood gas. Treatment is generally with oxygen therapy and methylene blue. Other treatments may include vitamin C, exchange transfusion, and hyperbaric oxygen therapy. Outcomes are generally good with treatment. Methemoglobinemia is relatively unc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzyl
In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure . Benzyl features a benzene ring () attached to a methylene group (). Nomenclature In IUPAC nomenclature, the prefix benzyl refers to a substituent, for example benzyl chloride or benzyl benzoate. Benzyl is not to be confused with phenyl with the formula . The term benzylic is used to describe the position of the first carbon bonded to a benzene or other aromatic ring. For example, is referred to as a "benzylic" carbocation. The benzyl free radical has the formula . The benzyl cation or phenylcarbenium ion is the carbocation with formula ; the benzyl anion or phenylmethanide ion is the carbanion with the formula . None of these species can be formed in significant amounts in the solution phase under normal conditions, but they are useful referents for discussion of reaction mechanisms and may exist as reactive intermediates. Abbreviations Benzyl is most commonly abbreviated Bn. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium-cooled Fast Reactor
A sodium-cooled fast reactor is a fast neutron reactor cooled by liquid sodium. The initials SFR in particular refer to two Generation IV reactor proposals, one based on existing liquid metal cooled reactor (LMFR) technology using mixed oxide fuel (MOX), and one based on the metal-fueled integral fast reactor. Several sodium-cooled fast reactors have been built and some are in current operation, particularly in Russia. Others are in planning or under construction. For example, in the US, TerraPower (using its Traveling Wave technology) is building its own reactors along with molten salt energy storage in partnership with GEHitachi's PRISM integral fast reactor design, under the ''Natrium'' appellation in Kemmerer, Wyoming. Aside from the Russian experience, Japan, India, China, France and the USA are investing in the technology. Fuel cycle The nuclear fuel cycle employs a full actinide recycle with two major options: One is an intermediate-size (150–600 MWe) sodium-cooled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Liquifaction
Coal liquefaction is a process of converting coal into liquid hydrocarbons: liquid fuels and petrochemicals. This process is often known as "coal to X" or "carbon to X", where X can be many different hydrocarbon-based products. However, the most common process chain is "coal to liquid fuels" (CTL). Historical background Coal liquefactions originally was developed at the beginning of the 20th century. The best-known CTL process is Fischer–Tropsch synthesis (FT), named after the inventors Franz Fischer and Hans Tropsch from the Kaiser Wilhelm Institute in the 1920s. The FT synthesis is the basis for indirect coal liquefaction (ICL) technology. Friedrich Bergius, also a German chemist, invented direct coal liquefaction (DCL) as a way to convert lignite into synthetic oil in 1913. Coal liquefaction was an important part of Adolf Hitler's four-year plan of 1936, and became an integral part of German industry during World War II. During the mid-1930s, companies like IG Farben and R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
