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991.
本文采用顶空-固相微萃取-毛细管气相色谱联用技术测定了洗涤制品中二噁烷量,使用50μmPEG/树脂萃取头。顶空平衡温度为80℃,萃取时间为40min。使用石英毛细管柱:30m×0.32mm×0.4μmi.d.内壁涂有5%二苯基(95%)二甲基硅氧烷固定液。外标法定量,二噁烷测定结果的相对标准偏差(RSD)为9.33%;在0.35μg/g~120μg/g范围,色谱峰面积与质量浓度之间呈良好线性关系,线性相关系数(R)为0.9998;回收率为98.7%~102%。 相似文献
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993.
Electrochemical incineration of dimethyl phthalate by anodic oxidation with
boron-doped diamond electrode 总被引:1,自引:0,他引:1
The anodic oxidation of aqueous solutions containing dimethyl phthalate (DMP) up to 125 mg/L with sodium sulfate (Na2SO4) as
supporting electrolyte within the pH range 2.0–10.0 was studied using a one-compartment batch reactor employing a boron-doped
diamond (BDD) as anode. Electrolyses were carried out at constant current density (1.5–4.5 mA/cm2). Complete mineralization was
always achieved owing to the great concentration of hydroxyl radical (.OH) generated at the BDD surface. The e ects of pH, apparent
current density and initial DMP concentration on the degradation rate of DMP, the specific charge required for its total mineralization
and mineralization current e ciency were investigated systematically. The mineralization rate of DMP was found to be pH-independent
and to increase with increasing applied current density. Results indicated that this electrochemical process was subjected, at least
partially, to the mass transfer of organics onto the BDD surface. Kinetic analysis of the temporal change of DMP concentration during
electrolysis determined by High Performance Liquid Chromatography (HPLC) revealed that DMP decay under all tested conditions
followed a pseudo first-order reaction. Aromatic intermediates and generated carboxylic acids were identified by Gas Chromatography-
Mass Spectrometry (GC-MS) and a general pathway for the electrochemical incineration of DMP on BDD was proposed. 相似文献
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995.
液相脉冲高压放电催化降解二甲基亚砜的研究 总被引:1,自引:0,他引:1
研究了液相脉冲高压放电Fenton催化对二甲基亚砜(dimethyl sulfoxide,DMSO)的降解.自制了脉冲上升前沿400 ns、放电重复率96.2 Hz、峰值电压20 kV的脉冲高压系统,它驱动液相高压放电发生.对脉冲高压电极侧壁做了绝缘以考察新型电极对单脉冲功率的影响.溶液电导率对液相高压放电H2O2产率和DMSO降解的影响及Fe(Ⅱ)和O2流量对液相高压放电DMSO降解的影响进行了考察,对液相高压放电Fenton催化降解DMSO的产物浓度、产物选择性随高压放电时间的变化也进行了研究.结果表明,新型电极的单脉冲功率随电导率增加有一极限值;溶液电导率和O2流量对DMSO降解起阻碍作用;Fe(Ⅱ)对DMSO降解起Fenton催化作用;液相高压放电Fenton催化降解DMSO的降解率在高压放电45min时为80%,可生化性至少提高32%~48%,最大能量效率按G37%计为0.008 7 mol/(kW.h).并对DMSO降解机制做了探讨.本研究显示了液相等离子体联用催化剂处理有机污染物的良好效果. 相似文献
996.
Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers.In this study,enantiomers of insecticide beta-cypermethrin (beta-CP) were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval assays.The enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism (CD) at 236 nm.Better separation could be achieved at lower temperature (e.g.,20°C) and with lower levels of polar modifiers.Pure enantiomers were obtained on Chiralcel OD.The CD spectra of enantiomers were recorded.By comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was determined.The individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked body.The 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration (e.g.,0.3 mg/L).The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects. 相似文献
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999.
高温液相色谱(High temperature liquid chromatography,HTLC)是一种操作温度在常温以上,通过改变温度来对分析仪器进行调节的液相色谱分析方法。实验采用接触预热法,检测器后设置阻尼阀的方式,通过在色谱柱后及检测器前直接设置冷却管的方式构建了分离效率高、峰容量大及可采用高黏度溶剂为流动相的HTLC系统。 相似文献
1000.