Search results for "Methylurea Compounds"
showing 3 items of 3 documents
A model for the formation and degradation of bound residues of the herbicide 14C-isoproturon in soil
1999
Abstract The humic monomer catechol was reacted with 14 C-isoproturon and some of its metabolites, including 14 C-4-isopropylaniline, in aqueous solution under a stream of oxygen. Only in the case of 14 C-4-isopropylaniline, incorporation in oligomers, in fulvic acid-like polymers, and in humic acid-like polymers was observed. The main oligomer was identified by mass spectrometry as 4,5-bis-(4-isopropylphenylamino)-3,5-cyclohexadiene-1,2-dione. Oligomers and polymers containing bound 14 C-4-isopropylaniline were subjected to biodegradation studies in a loamy agricultural soil during 55 days by quantifying 14 CO 2 evolved. In all cases, significant mineralization rates could be determined, w…
Modeling of an annular photocatalytic reactor for water purification: oxidation of pesticides.
2004
Photocatalytic oxidation (PCO) over titanium dioxide (TiO2) is a “green” sustainable process for the treatment and purification of water and wastewater. However, the application of PCO for wastewater treatment on an industrial scale is currently hindered by a lack of simple mathematical models that can be readily applied to reactor design. Current models are either too simplistic or too rigorous to be useful in photocatalytic reactor design, scale-up, and optimization. In this paper a simple mathematical model is presented for slurry, annular, photocatalytic reactors that still retains the essential elements of a rigorous approach while providing simple solutions. The model extends the appl…
Effect of cropping cycles and repeated herbicide applications on the degradation of diclofop-methyl, bentazone, diuron, isoproturon and pendimethalin…
2002
A greenhouse study was conducted to investigate the ability of four crops (wheat, corn, oilseed rape and soybean) to influence the degradation of bentazone, diclofop-methyl, diuron, isoproturon and pendimethalin in soil. The present study showed that microbial biomass-carbon was significantly higher in planted soils than in bulk soil, especially with wheat and corn, after several cropping cycles. The biomass in corn and soybean planted soils was adversely affected by bentazone but recovered after three cropping cycles. In wheat-planted soils, diclofop-methyl application resulted in persistent increase of the amount of microbial biomass. Bentazone did not show accelerated degradation even af…