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see Office of Price AdministrationOffice of Price Administration
(OPA), U.S. federal agency in World War II, established to prevent wartime inflation. The OPA issued (Apr., 1942) a general maximum-price regulation that made prices charged in Mar., 1942, the ceiling prices for most commodities.
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In a classical temple, a cavity which receives a roof beam.
References in periodicals archive ?
Several methods are suitable for the determination of amino acids (AAs) in biological fluids, including gas chromatography [1,2], reversed-phase chromatography with precolumn derivatization with various reagents such as orthophthalaldehyde (OPA) [3-6], 9-fluorenylmethyl-chloroformate [7], phenylisothiocyanate (PITC) [8, 9], dimethylaminonaphthalenesulfonyl chloride [10], dimethylaminoazobenzenesulfonyl chloride [10], 4-fluoro7-nitrobenzo-2-oxa-1,3-diazole [11], and ion-exchange chromatography with postcolumn derivatization utilizing OPA [12] or ninhydrin [13,14].
Plasma amino acid determinations by reversed-phase HPLC: improvement of the orthophthalaldehyde method and comparison with ion-exchange chromatography.