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Microwave chemistry is the science of applying microwave radiation to chemical reactions.〔''Microwaves in organic synthesis'', Andre Loupy (ed), Wiley-VCH, Weinheim, 2006, http://www.organic-chemistry.org/books/reviews/3527305149.shtm〕〔''Microwaves in organic synthesis. Thermal and non-thermal microwave effects'', Antonio de la Hoz, Angel Diaz-Ortiz, Andres Moreno, Chem. Soc. Rev., 2005, 164-178 〕〔''Developments in Microwave-assisted Organic Chemistry''. C. Strauss, R. Trainor. Aust. J. Chem., 48 1665 (1995).〕〔''Dry media reactions'' M. Kidwai Pure Appl. Chem., Vol. 73, No. 1, pp. 147–151, 2001.()〕〔''Microwaves in Organic and Medicinal Chemistry'', 2nd, Completely Revised and Enlarged Edition, Wiley-VCH, Weinheim, 2012 http://eu.wiley.com/WileyCDA/WileyTitle/productCd-3527331859.html〕 Microwaves act as high frequency electric fields and will generally heat any material containing mobile electric charges, such as polar molecules in a solvent or conducting ions in a solid. Polar solvents are heated as their component molecules are forced to rotate with the field and lose energy in collisions. Semiconducting and conducting samples heat when ions or electrons within them form an electric current and energy is lost due to the electrical resistance of the material. Microwave heating in the laboratory began to gain wide acceptance following papers in 1986,〔''The use of microwave ovens for rapid organic synthesis'' Richard Gedye, Frank Smith, Kenneth Westaway, Humera Ali, Lorraine Baldisera, Lena Laberge and John Rousell Tetrahedron Letters Volume 27, Issue 3, 1986, Pages 279-282 〕 although the use of microwave heating in chemical modification can be traced back to the 1950s. Although occasionally known by such acronyms as 'MEC' (Microwave-Enhanced Chemistry) or ''MORE synthesis'' (Microwave-organic Reaction Enhancement), these acronyms have had little acceptance outside a small number of groups. ==Heating effect== Conventional heating usually involves the use of a furnace or oil bath, which heats the walls of the reactor by convection or conduction. The core of the sample takes much longer to achieve the target temperature, e.g. when heating a large sample of ceramic bricks. Microwave heating is able to heat the target compounds without heating the entire furnace or oil bath, which saves time and energy. It is also able to heat sufficiently thin objects throughout their volume (instead of through its outer surface), in theory producing more uniform heating. However, due to the design of most microwave ovens and to uneven absorption by the object being heated, the microwave field is usually non-uniform and localized superheating occurs. Different compounds convert microwave radiation to heat by different amounts. This selectivity allows some parts of the object being heated to heat more quickly or more slowly than others (particularly the reaction vessel). Microwave heating can have certain benefits over conventional ovens: * reaction rate acceleration * milder reaction conditions * higher chemical yield * lower energy usage * different reaction selectivities Microwave chemistry is applied to organic chemistry 〔R.Cecilia, U.Kunz, T.Turek. "Possibilities of process intensification using microwaves applied to catalytic microreactors" Chem. Eng. Proc. Volume 46, Issue 9, Pages 870-881 (September 2007)〕 and to inorganic chemistry. 〔Martín-Gil J, Martín-Gil FJ, José-Yacamán M, Carapia-Morales L and Falcón-Bárcenas T. "Microwave-assisted synthesis of hydrated sodium uranyl oxonium silicate". ''Polish J. Chem'', 2005, 1399-1403.〕 〔J. Prado-Gonjal, M.E. Villafuerte-Castrejón,L. Fuentes and E. Morán. "Microwave-hydrothermal synthesis of BiFeO3". "Mat.Res.Bull" 44 (2009) 1734-1737〕 〔K.J.Rao, B.Vaidhyanathan, M.Ganduli, P.A.Ramakrishnan, Chem.Mater. 11, 1999, 882〕 〔J.Zhao, W.Yan, Modern Inorganic Synthetic Chemistry, Chapter 8 (2011) 173〕 〔R.K.Sahu, M.L.Rao, S.S.Manoharan, Journal of Materials Science 36 (2001) 4099〕 〔D.M.P.Mingos, D.Baghurst, Chem.Soc.Rev 20 (1991) 1〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「microwave chemistry」の詳細全文を読む スポンサード リンク
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