液相微萃取-气相色谱／质谱联用测定饮用水及水源水中的土臭素和2-甲基异冰片

土臭素（GSM）和2-甲基异冰片（MIB）是引发水体土霉味的主要物质。液相微萃取以其有机溶剂耗量少、操作简单快速、成本低、不造成二次污染等优点，而被广泛应用。本文比较了两种液相微萃取技术对GSM和MIB的富集效果，并应用于实际水样的分析

多环芳烃的样品前处理技术研究进展

多环芳烃(PAHs)是一类致癌、致畸、致突变的持久性有机物污染物,广泛存在于大气、水、土壤和生物等介质中.由于PAHs基体复杂并且含量很低,所以样品的净化和富集尤为重要.本文综述了近5年来国内外有关PAHs的样品前处理技术和方法的基本原理和代表性应用,包括液相微萃取、分散液液微萃取、固相微萃取、搅拌子吸附萃取、微耗损固相微萃取、分散固相微萃取法,比较了各方法的优缺点,并对PAHs的样品前处理技术的发展进行了展望

Ｒesearch progress on sample pretreatment techniques for polycyclic aromatic hydrocarbons

多环芳烃(PAHs)是一类致癌、致畸、致突变的持久性有机物污染物,广泛存在于大气、水、土壤和生物等介质中.由于PAHs基体复杂并且含量很低,所以样品的净化和富集尤为重要.本文综述了近5年来国内外有关PAHs的样品前处理技术和方法的基本原理和代表性应用,包括液相微萃取、分散液液微萃取、固相微萃取、搅拌子吸附萃取、微耗损固相微萃取、分散固相微萃取法,比较了各方法的优缺点,并对PAHs的样品前处理技术的发展进行了展望

Advances in the preparation and application of estradiol molecularly imprinted polymers

The abuse and residues of estradiol environmental endocrine disruptors are very harmful to the organism and the environment，and estradiol is difficult to be detected owing to the low content and the complicated matrices interferences． Molecularly imprinted polymers ( MIPs) prepared by molecular imprinting technology have versatile advantages of the high selectivity， high stability and easy preparation． Consequently，MIPs have gained popularity in the analysis of hazardous targets at low levels in complicated matrices． Among MIPs，a number of studies based on E2-MIPs have been reported． Herein，related preparation methods and applications of E2-MIPs are reviewed since 2014-2018，focusing on free radical polymerization，sol-gel polymerization and the new surface imprinting methods for E2-MIPs，and their applications in sample pretreatment，sensor and membrane separation．Finally，the challenges and perspectives of E2-MIPs are proposed

Determination of four phenolic estrogens in water samples by pressure-assisted electrokinetic injection coupled with capillary electrophoresis

在毛细管电泳的胶束电动色谱(MEKC)模式下,采用压力辅助电动进样(PAEKI)的进样方式在线富集4种酚类雌激素(PEs)。对影响PAEKI的进样电压、进样时间等进行考察,并与传统的压力进样比较。结果表明,在最优的PAEKI条件下(-9 k V,0.3 psi(约2.1 k Pa),0.4 min),4种PEs在7 min内基线分离,线性关系良好,相关系数(r)大于0.993 6,己烷雌酚和双烯雌酚的线性范围为0.05~5 mg/L、双酚A和己烯雌酚的线性范围为0.1~10m g/L;检出限(S/N=3)为0.007 1~0.017 m g/L,富集倍数为11~15。使用该MEKC-PAEKI法对自来水和湖水水样进行测定,得到定量限(S/N=10)分别为0.029~0.064 mg/L和0.033~0.079 mg/L;加标回收率为75.6%~110.1%,相对标准偏差(n=5)为4.6%~11.8%。PAEKI不需要使用其他试剂,只需对电泳仪的参数进行适当调整即可实现对分析物的在线富集,简单、快速、自动化程度高

Determination of organophosphorus and carbamate insecticide residues in food and water samples by solid phase extraction coupled with capillary liquid chromatography

A method was established for the simultaneous separation and determination of one organophosphorus and three carbamate insecticide residues in food and water samples by solid phase extraction (SPE) followed by analysis using a home-made capillary liquid chromatogram. Various parameters possibly affecting the efficiencies of capillary liquid chromatography (CLC) and SPE were investigated in detail, such as type of SPE column, pH value of samples, type and volume of elution solvent, flow rate of loading sample, salt effect, loading volume, detection wavelength, and type and ratio of mobile phases. Under the optimized experimental conditions, the four insecticides were separated completely within 6 min. The limits of detection and limits of quantification were 0.35-1.20 μg/kg and 1.17-4.00 μg/kg, respectively. Satisfactory recoveries of the SPE-CLC method were achieved for spiked food samples of tomato, cucumber and apple ranging from 72.41% to 107.15% with the relative standard deviations (RSDs) no more than 8.12%, and for spiked tap/lake water samples ranging from 71.45% to 109.25% with the RSDs no more than 9.28%. The method can meet the requirements for multi-residue analysis of insecticides

基于CTAC改性活性炭的信封式膜包用于水溶液中六价铬去除

以阳离子表面活性剂十六烷基三甲基氯化铵(CTAC)改性粉末椰壳活性炭为载体制备了聚丙烯信封式膜包,用于水溶液中六价铬(Cr(Ⅵ))的吸附去除.对CTAC改性活性炭进行了扫描电镜和红外光谱表征,研究了膜包对水溶液中Cr(Ⅵ)的吸附去除性能.系统考察了改性活性炭的投加量、微孔滤膜的孔径、溶液pH值、吸附温度和吸附时间等因素对吸附效果的影响.实验结果表明,将50 mg改性活性炭包覆在孔径为3.0 μm的膜内制成信封式膜包,在25 ℃条件下对pH值为2的Cr(Ⅵ)溶液吸附3 h,去除效率高于99.0%.室温下(25 ℃)对Cr(Ⅵ)的静态吸附行为符合Langmuir等温吸附模型,动态吸附过程符合准二级动力学模型.该膜包成功用于3种实际水样中Cr(Ⅵ)的吸附去除.CTAC改性与信封式膜包的结合使用大大简化了操作步骤,降低了成本.该研究有望为污水处理提供潜在、高效的吸附材料和吸附方法

Envelope membrane packed with CTAC modified active carbon for Cr(Ⅵ) removal from aqueous solution

Polypropylene envelope - type membrane-package was prepared by using cationic surfactant hexadecyl trimethyl ammonium chloride (CTAC) modified coconut-shell activated carbon powder as carrier,and was applied for adsorptive-removal of Cr(Ⅵ) from aqueous solution. The CTAC modified activated carbon was well characterized by scanning electron microscopy and infrared spectra,and the adsorption performances of envelope-type membrane-package towards Cr(Ⅵ) were systematically studied. The influences of main parameters on the adsorption properties were investigated in detail,including the amount of modified activated carbon,pore diameter of microporous filter membrane,solution pH value,adsorption temperature and adsorption time. Accordingly,high removal efficiency above 99.0% was attained,when the membrane-package composed of 50 mg modified activated carbon in a membrane with pore diameter of 3.0 mum was employed to adsorb Cr(Ⅵ) with solution pH of 2 for 3 h at 25 ℃. The static adsorption behavior of Cr(Ⅵ) at room temperature (25 ℃) was well fitted with the Langmuir isothermal adsorption model, and the dynamic adsorption process obeyed the pseudo second-order kinetic model. Furthermore,the membrane-package was successfully applied to adsorptive-removal of Cr(Ⅵ) from three kinds of real water samples. The combined use of CTAC modification and envelope-type membrane-package greatly simplified operation steps and reduced experimental cost. The present study could provide a potential and effective adsorption material and adsorption method for actual sewage treatment