Extraction of 17β-estradiol in water using non-imprinted polymer submicron particles in membrane filters

17β-Estradiol (E2) is an endocrine disrupting chemical of harm to both animals and human beings at a low concentration level (ng/L). It cannot be completely removed by wastewater treatments, and is often detected in both environment and drinking waters. The purpose of this feasibility study, towards environmental engineering in the field of water analysis and treatment, was to remove E2 by extraction using non-imprinted polymer (NIP) submicron particles. Experimental results showed that 0.5 mg/L of E2 could be completely extracted by adding 10 mg of NIP particles directly into 10 mL of water. However, the extraction efficiency decreased to 64% for 100 mL of water. prefilling the NIP particles inside a membrane filter showed a potential for water treatment of a large volume, requiring no effort to distribute the particles uniformly in the water. High extraction efficiency (80 ± 10)% for E2 was achieved for 100 mL of water. A total mass of 0.29 mg E2 was extracted from 1000 mL of water containing 0.8 mg/L E2 (by using only 10 mg of NIP particles). Both efficiency and mass capacity can be increased, by scaling up the amount of NIP particles, towards environmental engineering applications.     

西安夏季大气亚微米颗粒物化学组成与来源的在线观测研究

西安作为汾渭平原地区最大的城市,大气颗粒物污染形势严峻.2017年夏季期间,在西安市浐灞生态园区运用气溶胶化学组分监测仪,对大气亚微米颗粒物中的非难挥发性组分(NR-PM1)进行了在线监测.观测期间NR-PM1的平均质量浓度为(30.1?±?15.4)μg???m?3.其中有机物含量最高,占NR-PM1总质量浓度的63...     

单纤维捕集过程中亚微米颗粒的布朗团聚

针对亚微米颗粒(0.1～0.5μm)在单纤维捕集过程中的布朗团聚规律,基于计算流体动力学-颗粒群平衡模型(CFD-PBM)对粉尘颗粒在单纤维捕集过程中的布朗团聚行为进行了数值模拟研究,采用分区法对颗粒群平衡方程(PBE)进行求解,综合考虑了停留时间、入口粉尘粒径、气流温度、Pe数对布朗团聚的影响,并将数值模拟与实验结果...     

饮用水中悬浮颗粒物对微生物聚集和消毒效果的影响

针对目前有关消毒剂胁迫下颗粒物对微生物保护作用机制尚不清晰,以饮用水中微生物为研究对象,通过构建静态模拟实验装置,解析消毒剂胁迫下针铁矿对微生物聚集和消毒效果的影响机制.结果表明,当未投加消毒剂氯时,针铁矿浓度对水中微生物失活率基本没有影响;而当有氯存在时,针铁矿促进氯的衰减、微生物胞外聚合物的分泌以及其聚集行为,进而...     

电增强环氧树脂基聚合物膜萃取水样中的硝基苯

以环氧树脂基聚合物膜为萃取相,在电场作用下富集目标物,与高效液相色谱(HPLC)联用,应用于环境水样中硝基苯污染物的测定.考察了电压大小、萃取时间、洗脱时间、离子强度和溶液pH值对电增强萃取效率的影响.实验结果表明,环氧树脂基聚合物膜的萃取量与膜上所施加的控制电位相关,阴极极化时,膜对硝基苯的萃取量增大;在阳极极化时,膜萃取量减小.在电压为-0.3kV,硝基苯溶液pH=4的条件下,萃取20min,得到该方法的检出限为0.015μg·mL-1,在0.05～3.0μg·mL-1范围内具有良好的线性关系,可决系数为0.9929,变异系数小于5%.用上述方法分析鱼塘水,硝基苯3种不同加标水平的回收率为79.8%～108.2%.结果表明,该方法既可用于环境水样品中的硝基苯去除又可用于检测.     

基于稳定同位素示踪的流域颗粒有机物质来源辨析

为有效控制流域水质污染,保证饮用水水源的水质安全,通过采集和测定流域内土壤、植物以及河流断面水体悬浮颗粒有机质(POM)在枯水期和丰水期的碳、氮稳定同位素值和C/N比值,对石头口门水库汇水流域水体POM的来源进行研究.结果表明,水体中POM主要来源于土壤有机质,其贡献为69.2%,藻类等大型水生生物和浮游植物的贡献分别为23.1%和7.7%.流域水体中POM的来源存在时空差异.丰水期,浮游植物和藻类等大型水生植物的贡献均为15.4%,而枯水期后者的贡献提高到了30.8%.水体POM主要来源于双阳河和饮马河下游的土壤有机质,说明该区域土壤侵蚀较重,易发生非点源污染;岔路河和饮马河上游支流小黄河,水体POM以浮游植物的贡献占主导,其贡献分别为86.3%和94.8%,这些区域侵蚀较弱,非点源污染发生的风险小;大中型水库区域的POM主要由藻类等大型水生植物贡献,表明悬浮颗粒物在进入水库后可能发生了明显沉积.     

臭氧氧化对陶瓷膜超滤工艺降低饮用水中浊度的影响

利用臭氧陶瓷膜超滤集成工艺,研究了臭氧对陶瓷膜超滤工艺处理不同浊度原水的影响.实验用陶瓷膜平均孔径为100 nm.结果表明,与不投加臭氧的情况相比,投加3 mg·L-1臭氧可将浊度为14、52、108和510 NTU原水的膜通量提高18.2％～104.9％,投加5 mg·L-1臭氧可将此值提高至21.7％ ～116.3％,而投加1～2 mg·L-1臭氧对膜通量的改善不明显.投加5mg·L-1臭氧可将CODMn的去除率提高至28.7％ ～46.9％,投加1～3 mg·L-1臭氧对CODMn的去除率无显著影响,膜出水有机物浓度有所升高.臭氧氧化后原水中小分子量有机物增多,降低了膜的有机物污染程度,有利于膜通量改善.集成工艺出水中2～3 μm颗粒物数量为10 ～36个·mL-1.臭氧氧化导致陶瓷膜过滤初期出水中颗粒物数量略微升高.本研究对于水中颗粒物通过陶瓷超滤膜孔的探讨,以及改善膜对颗粒物的去除具有重要的指导意义.     

三油酸甘油脂-醋酸纤维素复合膜测定水中有机氯农药生物有效性

以异狄氏剂、狄氏剂和p,p'-滴滴涕3种持久性有机氯农药为研究对象,通过室内模拟实验,验证了三油酸甘油脂-醋酸纤维素复合膜(TECAM)富集水中自由溶解态疏水性有机物的假设,研究了水中溶解性有机碳对TECAM富集3种有机氯农药的影响,并与相同暴露条件下日本青鳉鱼的富集结果进行了比较.结果表明,TECAM只富集水中自由溶解形态的疏水性有机物;水中存在的溶解性有机碳会降低3种有机氯农药被TECAM和青鳉富集的可利用性;TECAM和青鳉的富集结果有很好的可比性.因此,TECAM能够用来预测疏水性有机污染物在不同溶解性有机碳含量的水中被鱼体富集的生物有效性.     

Catalytic reductive dechlorination of p–chlorophenol in water using Ni/Fe nanoscale particles

Nanoscale bimetallic Ni/Fe particles were synthesized from the reaction of sodium borohydride （NaBH4） with reduction of Ni^2＋ and Fe^2＋ in aqueous solution. The obtained Ni/Fe particles were characterized by TEM （transmission electron microscope）, XRD （X-ray diffractometer）, and N2-BET. The dechlorination activity of the Ni/Fe was investigated using p-chlorophenol （p-CP） as a probe agent. Results demonstrated that the nanoscale Ni/Fe could effectively dechlorinate p-CP at relatively low metal to solution ratio of 0.4 g/L （Ni 5 wt%）. The target with initial concentration ofp-CP 0.625 mmol/L was dechlorinted completely in 60 rain under ambient temperature and pressure. Factors affecting dechlorination efficiency, including reaction temperature, pH, Ni loading percentage over Fe, and metal to solution ratio, were investigated. The possible mechanism of dechlorination ofp-CP was proposed and discussed. The pseudo-first- order reaction took place on the surface of the Ni/Fe bimetallic particles, and the activation energy of the dechlorination reaction was determined to be 21.2 kJ/mol at the temperature rang of 287-313 K.