Modified Edman degradation applied to hemoglobin for monitoring occupational exposure to alkylating agents

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.     

环氧氯丙烷改性稻草的光降解研究

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。     

Synthesis,crystal structure,photodegradation kinetics and photocatalytic activity of novel photocatalyst ZnBiYO4

ZnBiYO4 was synthesized by a solid-state reaction method for the first time. The structural and photocatalytic properties of ZnBiYO4 were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and UV–Vis diffuse reflectance.ZnBiYO4 crystallized with a tetragonal spinel structure with space group I41/A. The lattice parameters for ZnBiYO4 were a = b = 11.176479  and c = 10.014323 . The band gap of ZnBiYO4 was estimated to be 1.58 e V. The photocatalytic activity of ZnBiYO4 was assessed by photodegradation of methyl orange under visible light irradiation. The results showed that ZnBiYO4 had higher catalytic activity compared with N-doped Ti O2 under the same experimental conditions using visible light irradiation. The photocatalytic degradation of methyl orange with ZnBiYO4 or N-doped Ti O2 as catalyst followed first-order reaction kinetics, and the first-order rate constant was 0.01575 and 0.00416 min-1for ZnBiYO4 and N-doped Ti O2, respectively. After visible light irradiation for 220 min with ZnBiYO4 as catalyst, complete removal and mineralization of methyl orange were observed. The reduction of total organic carbon, formation of inorganic products, SO2-4and NO-3, and evolution of CO2 revealed the continuous mineralization of methyl orange during the photocatalytic process. The intermediate products were identified using liquid chromatography–mass spectrometry. The ZnBiYO4/(visible light) photocatalysis system was found to be suitable for textile industry wastewater treatment and could be used to solve other environmental chemical pollution problems.     

载银TiO2光催化降解2,4-二氯苯酚水溶液的研究

以新型载银TiO₂为催化剂,太阳光为光源,对2,4-二氯苯酚水溶液进行了光降解。结果表明,载银TiO₂催化剂的光解效率是单纯TiO₂的1.9倍;经回归分析,由Langmiur-HinsheiWood方程计算出的反应速率R值与实验值的最大偏差不超过6.5%。证明该光解反应是非均相催化动力学反应。      

UV-Vis/Fe(Ⅲ)/H2O2体系对水中雌酮的光降解

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。