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71.
以250W照明金属卤化物灯为光源,研究了水中雌酮(E1)在UV-Vis/Fe(Ⅲ)/H2O2体系中的光降解;考查了初始pH、Fe(Ⅲ)、H2O2、E1初始浓度对E1光降解的影响。结果表明,UV-Vis/Fe(Ⅲ)/H2O2体系能有效地光降解E1,在[Fe(Ⅲ)30-20.8μmol/L、[H2O2]0=1664μmol/L、pH=3.0时,光照160min,18.5btmol/L E1的光降解率可达98.4%;在pH3.0~8.0范围内,pH初始值越小,E1降解率越大,反应初始速率越大;实验条件下,Fe(Ⅲ)、H2O2初始浓度越大,E1降解率越大,反应初始速率越大;E1初始浓度越低,E1降解率越大,反应初始速率越小。pH=3.0,实验浓度范围内的表观动力学方程为:dCE1/dt=0.00093[H2O2]^0.47[Fe(Ⅲ)]^0.62[E1]0.24;Fe(Ⅲ)是影响反应速率的主要浓度因素。 相似文献
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A method that can be used for the monitoring of exposure to alkylating agents in the environment is presented. It is based on the quantification of alkylated N‐terminal valines in hemoglobin, using a modified Edman degradation procedure. The detection limit (GC/electron capture detector or GC/MS) is increased by two magnitudes of ten when using pentafluorophenyl isothiocyanate instead of phenyl isothiocyanate in the derivatization step. As little as one nmole N‐(—2 hydroxyethyl)valine per gram hemoglobin can be detected under practical conditions. 相似文献
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The fate of imazapyr (2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid), a broad-spectrum herbicide in the imidazolinone family, has been studied upon UV irradiation. Most of the photoproducts occurring during the photodegradation have been characterized by means of liquid chromatography and mass spectrometry coupled techniques (LC-MS). The use of high resolution mass spectrometry has allowed to maximize the chemical information obtained from a single LC-MS analysis. The degradation of a 10?ppm imazapyr solution leads to pyridine derivatives which remain in solution during 50–100?h while the imazapyr is completely degraded after 6?h. 相似文献
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环氧氯丙烷改性稻草的光降解研究 总被引:2,自引:0,他引:2
利用QUV耐候加速仪对天然稻草、预处理稻草和环氧氯丙烷改性稻草进行了光降解老化实验,研究其在光降解后的失重率和红外光谱图变化。结果表明,经过576h光降解实验后,改性稻草的失重率接近于天然稻草的失重率,分别为2.50%和2.49%,而预处理稻草的失重率仅为1.71%。红外光谱图显示,天然稻草光降解后,木质素含量明显降低;预处理后稻草中的木质素和半纤维素被去除;预处理稻草经环氧氯丙烷改性后,醚键增多,改性稻草光降解后-CH2和-CH2的含量降低,说明脂肪族化合物发生分解。 相似文献