62 research outputs found
Stereochemical studies of oligomers. XV. Structure of 2-methyl-1,4-butanediyl dibenzoate, C19H20O4
Municipal Solid Waste Incineration Bottom Ash: Characterization and Kinetic Studies of Organic Matter
Analysis of Aromatic Sulfur Compounds in Gas Oils Using GC with Sulfur Chemiluminescence Detection and High-Resolution MS
Characterization of honey amino acid profiles using high-pressure liquid chromatography to control authenticity
A study on the effects of reaction conditions on the characteristics of resol resins for foams by statistical analysis
Photochemical degradation of acifluorfen in aqueous solution
To elucidate the photochemical behavior of diphenyl ether herbicides in superficial waters, the photodegradation of acifluorfen, 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid (CAS Registry No. 50594-66-6), was studied in water and acetonitrile. All experiments were carried out under laboratory conditions using a solar simulator (xenon arc) or jacket Pyrex reaction cell equipped with a 125 W high-pressure mercury lamp. The calculated polychromatic quantum efficiencies (Φsolvent) of acifluorfen in different solvents are as follows (units are degraded molecules photon-1): Φwater = 10-4, Φacetronitile = 10-4, Φmethanol = 10-4, and Φhexane = 10-2. The results obtained in this work are in good agreement with the literature value of monochromatic quantum yield. HPLC-MS analysis (APCI and ESI in positive and negative modes) was used to identify acifluorfen photoproducts. These results suggest that the photodegradation of acifluorfen proceeds via a number of reaction pathways: (1) decarboxylation, (2) dehalogenation, (3) substitution of chlorine group by hydroxyl or hydrogen groups, and (4) cleavage of ether linkage, giving phenols. Photorearrangement products were studied by other investigators. No such products were observed. In addition, it was found that the trifluoro functional group on acifluorfen was not affected by any transformation, and no products of a nitro group reduction were found
Optimizing the extraction and analysis of DHEA sulfate, corticosteroids and androgens in urine: application to a study of the influence of corticosteroid intake on urinary steroid profiles
Carbon-13 NMR studies of monohydroxylated and monochlorinated derivatives ofZ- andE-p-menthanes
Physicochemical Studies of PMR Resins. I: Reaction Mechanism and Kinetics at Room Temperature
Covalent Modification of Carbon Surfaces by Aryl Radicals Generated from the Electrochemical Reduction of Diazonium Salts
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