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Heptafluorobutyric Acid
Perfluorobutanoic acid (PFBA) is a perfluoroalkyl carboxylic acid with the formula C3F7CO2H. As the perfluorinated derivative of butyric acid, this colourless liquid is prepared by electrofluorination of the corresponding butyryl fluoride.{{Citation , last=Siegemund , first=Günter , title=Fluorine Compounds, Organic , date=2000 , work=Ullmann's Encyclopedia of Industrial Chemistry , pages= , place=Weinheim, Germany , publisher=Wiley-VCH Verlag GmbH & Co. KGaA , language=en , doi=10.1002/14356007.a11_349 , isbn=978-3-527-30673-2 , last2=Schwertfeger , first2=Werner , last3=Feiring , first3=Andrew , last4=Smart , first4=Bruce , last5=Behr , first5=Fred , last6=Vogel , first6=Herward , last7=McKusick , first7=Blaine Applications PFBA has a variety of niche applications in analytical and synthetic chemistry. It is an ion pair reagent for reverse-phase HPLC. It is used in the sequencing, synthesis, and solubilizing of proteins and peptides. Esters derived from PFBA readily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hebrew Free Burial Association
The Hebrew Free Burial Association (HFBA) was established in 1888 as a free burial society serving the residents of Manhattan's Lower East Side. It was incorporated as a non-profit organization with the name of Chebra Agudas Achim Chesed Shel Emeth (The Society of the Brotherhood of True Charity ) on January 25, 1889. As the need grew in adjacent Jewish communities, HFBA also grew to serve the broader metropolitan area of New York City. HFBA is currently the largest free burial society outside of Israel. In 1965, it changed its official name to Chebra Agudas Achim Chesed Shel Emeth Hebrew Free Burial Association, Inc. Overview The primary function of HFBA is to provide free burials to all indigent Jews in New York City, regardless of denominational affiliation. Burials are conducted in accordance with Jewish law. If not for HFBA, an indigent person in New York City could be buried in a mass grave in Potter's Field after lying in a morgue for up to a month, or may be transferred ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfluoroalkyl Carboxylic Acid
Perfluoroalkyl carboxylic acids (PFCAs), or perfluorocarboxylic acids are compounds of the formula CnF(2n+1)CO2H that belong to the class of per- and polyfluoroalkyl substances. The simplest example is trifluoroacetic acid. These compounds are organofluorine analogues of ordinary carboxylic acids, but they are stronger by several pKa units and they exhibit great hydrophobic character. Perfluoroalkyl dicarboxylic acids (PFdiCAs) are also known, e.g. C2F4(CO2H)2.Günter Siegemund, Werner Schwertfeger, Andrew Feiring, Bruce Smart, Fred Behr, Herward Vogel, Blaine McKusick "Fluorine Compounds, Organic" Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. Applications Trifluoroacetic acid is a widely employed acid, used for example in the synthesis of peptides. Its esters are useful in analytical chemistry. Longer-chain perfluoroalkyl carboxylic acids, e.g. with five to nine carbons, are useful fluorosurfactants and emulsifiers used in the production of po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Formula
In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and ''plus'' (+) and ''minus'' (−) signs. These are limited to a single typographic line of symbols, which may include subscripts and superscripts. A chemical formula is not a chemical name, and it contains no words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulae can fully specify the structure of only the simplest of molecules and chemical substances, and are generally more limited in power than chemical names and structural formulae. The simplest types of chemical formulae are called ''empirical formulae'', which use letters and numbers indicating the numerical ''proportions'' of ato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butyric Acid
Butyric acid (; from grc, βούτῡρον, meaning "butter"), also known under the systematic name butanoic acid, is a straight-chain alkyl carboxylic acid with the chemical formula CH3CH2CH2CO2H. It is an oily, colorless liquid with an unpleasant odor. Isobutyric acid (2-methylpropanoic acid) is an isomer. Salts and esters of butyric acid are known as butyrates or butanoates. The acid does not occur widely in nature, but its esters are widespread. It is a common industrial chemical and an important component in the mammalian gut. History Butyric acid was first observed in impure form in 1814 by the French chemist Michel Eugène Chevreul. By 1818, he had purified it sufficiently to characterize it. However, Chevreul did not publish his early research on butyric acid; instead, he deposited his findings in manuscript form with the secretary of the Academy of Sciences in Paris, France. Henri Braconnot, a French chemist, was also researching the composition of butter and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrofluorination
Electrochemical fluorination (ECF), or electrofluorination, is a foundational organofluorine chemistry method for the preparation of fluorocarbon-based organofluorine compounds.G. Siegemund, W. Schwertfeger, A. Feiring, B. Smart, F. Behr, H. Vogel, B. McKusick "Fluorine Compounds, Organic" in "Ullmann’s Encyclopedia of Industrial Chemistry" 2005, Wiley-VCH, Weinheim. The general approach represents an application of electrosynthesis. The fluorinated chemical compounds produced by ECF are useful because of their distinctive solvation properties and the relative inertness of carbon–fluorine bonds. Two ECF synthesis routes are commercialized and commonly applied: the Simons process and the Phillips Petroleum process. It is also possible to electrofluorinate in various organic media.Fred G. Drakesmith "Electrofluorination of Organic Compounds" Topics in Current Chemistry,Vol. 193, Springer, Berlin-Heidelberg, 1997. Prior to the development of these methods, fluorination with fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Phase High Performance Liquid Chromatography
Reverse or reversing may refer to: Arts and media * ''Reverse'' (Eldritch album), 2001 * ''Reverse'' (2009 film), a Polish comedy-drama film * ''Reverse'' (2019 film), an Iranian crime-drama film * ''Reverse'' (Morandi album), 2005 * ''Reverse'' (TV series), a 2017–2018 South Korean television series *"Reverse", a 2014 song by SomeKindaWonderful * REVERSE art gallery, in Brooklyn, NY, US *Reverse tape effects including backmasking, the recording of sound in reverse * '' Reversing: Secrets of Reverse Engineering'', a book by Eldad Eilam *''Tegami Bachi: REVERSE'', the second season of the ''Tegami Bachi'' anime series, 2010 Driving * Reverse gear, in a motor or mechanical transmission * Reversing (vehicle maneuver), reversing the direction of a vehicle * Turning a vehicle through 180 degrees Sports and games *Reverse (American football), a trick play in American football *Reverse swing, a cricket delivery *Reverse (bridge), a type of bid in contract bridge Technology * Reve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
