改进型生物质阴离子交换纤维制备及吸附性能

用氢氧化钠水溶液预处理,以乙二胺作交联剂,采用环氧氯丙烷和二甲胺对网状植物丝瓜络纤维进行化学改性,制备出改性丝瓜络阴离子交换纤维(LS-AEF),重点探讨了LS-AEF的形态特征并对其形态特征进行了表征分析,还考察了碱预处理对产品吸附水体中的NO-3的影响。研究结果表明,(1)LS-AEF引入带正电的胺基基团,可以提高对NO-3的吸附性能;(2)乙二胺剂量对产品吸附性能影响比较大,最佳剂量为9 mL,吸附率达到75%;(3)碱性预处理能够显著提高产品的吸附性能,碱处理前后的产品吸附率分别为76%和85%;(4)吸附过程符合伪二级动力学方程。     

制革废水中丙烯酸类鞣剂的膜分离特征

针对3种丙烯酸类鞣剂超滤(UF)、反渗透(RO)分离参数进行了实验研究,探索其在废水深度处理中膜去除的可行性,研究结果表明,3种鞣剂在分离参数:浓度为200 mg/L,超滤的操作压力(P UF)为0.11 MPa,反渗透的操作压力(P RO)为0.4 MPa的条件下UF-RO分离,效果最好。其次,丙烯酸类鞣剂对膜通量影响较大,导致产生的清液较少,所以用UF、RO处理含有这类物质的制革废水时,应尽可能对废水进行预处理。最后,丙烯酸类鞣剂分子中含有极性较强的基团时,粒径分离效果不同。     

生物炭对铅离子的吸附性能

以废弃松木屑为原料,采用控制热分解法制备了生物炭。运用BET和FTIR等技术对生物炭进行了表征,考察了生物炭对铅离子的吸附效果,并探讨了吸附机理。表征结果显示,700℃氨气处理的生物炭,其比表面积和总孔体积显著增大。实验结果表明:生物炭对铅离子的吸附效果优于普通活性炭,且以700℃氨气处理的生物炭为最佳;随溶液pH的升高生物炭对铅离子的去除率增大,当pH为4~6时去除效果较好;在溶液pH为6、初始铅离子质量浓度为50 mg/L、吸附剂加入量为1 g/L、吸附时间为6 h的条件下,700℃氨气处理的生物炭对铅离子的去除率达99%以上;700℃氨气处理的生物炭的Langmuir吸附常数和Freundlich吸附常数远大于普通活性炭和其他工艺的生物炭;铅离子在生物炭上的吸附过程符合拟二级动力学方程。     

Food utilization and growth of cutworm Spodoptera litura Fabricius larvae exposed to nickel,and its effect on reproductive potential

Food utilization and growth of the 5th and 6th instar Spodoptera litura Fabricius larvae, and its effect on reproduction potential was evaluated by feeding larvae diets with different doses of Ni for 3 generations. Dose-dependent relationships between Ni levels and food consumption and growth were variable with different larval developmental period and Ni exposure duration. RCR, AD and RGR of the 6th instar larvae were much more affected by Ni exposure than those of 5th instar larvae, and the effects were strongest in the 3rd generation. It was found that RCR was significantly stimulated after 1 and 20 mg kg⁻¹ Ni exposure, while AD was significantly inhibited after 1, 5, 10 and 40 mg kg⁻¹ Ni exposure. However, lower levels of Ni (?5 mg kg⁻¹) significantly increased and higher levels of Ni (?10 mg kg⁻¹) significantly decreased RGR. In 3 successive generations, 10 mg kg⁻¹ Ni significantly increased the ECI and ECD of the 5th instar larvae, and 5 mg kg⁻¹ Ni significantly increased the ECD of the 6th instar larvae. However, ECD were all significantly inhibited with 20 mg kg⁻¹ Ni exposure. Results also revealed that durations of larvae were shortened at low levels of Ni, but extended at high levels of Ni. Fecundity was inhibited by the highest Ni doses in each generation, while improved by low Ni doses in the 3rd generation. Hatching rates in all treatments were significantly decreased in a Ni dose-dependent manner. Study indicated that effects of Ni on these parameters were predominant with the increasing Ni exposure period.     

Detection,occurrence and fate of 22 psychiatric pharmaceuticals in psychiatric hospital and municipal wastewater treatment plants in Beijing,China

The liquid chromatography–electrospray ionization-tandem mass spectrometer (LC–MS/MS) method coupled with an automated solid-phase extraction procedure has been developed to identify 22 psychiatric pharmaceuticals, including seven anxiolytic-sedative-hypnotics, six antidepressants, and nine anti-schizophrenia drugs, in wastewater samples from two psychiatric hospital wastewater treatment plants (P-WWTPs) and three municipal wastewater treatment plants (M-WWTPs) in Beijing, China. Analyte recoveries from spiking experiments in the WWTP influent and effluent at three concentrations ranged from 70% to 110%, excluding sulpiride, ziprasidone, and olanzapine. Method detection limits for five, eight, and nine analytes in the WWTP influent and effluent were 20–80, 1–16, and <1 ng L^?1, respectively. High psychiatric pharmaceutical concentrations (e.g., ～942 ng L^?1oxazepam, 5552–12,782 ng L^?1 clozapine, 2762–9832 ng L^?1sulpiride, and 2030–4967 ng L^?1quetiapine) were frequently observed in P-WWTP influent compared to M-WWTPs. Although P-WWTPs typically had higher removal rates, significantly higher concentrations of the target compounds were observed in the P-WWTP secondary effluent than in the M-WWTP influent (e.g., ～752 ng L^?1oxazepam, ～8183 ng L^?1 clozapine, ～10,833 ng L^?1sulpiride, and ～1168 ng L^?1quetiapine). Thus, the discharge control of psychiatric pharmaceuticals from psychiatric hospitals requires improvement.     

Bioaccumulation and uptake routes of perfluoroalkyl acids in Daphnia magna

Perfluoroalkyl acids (PFAs), one kind of emerging contaminants, have attracted great attentions in recent years. However, the study about their bioaccumulation mechanism remains scarce. In this research, the bioaccumulation of six kinds of PFAs in water flea Daphnia magna was studied. The uptake rates of PFAs in D. magna ranged from 178 to 1338 L kg^?1 d^?1, and they increased with increasing perfluoroalkyl chain length; the elimination rates ranged from 0.98 to 2.82 d^?1. The bioaccumulation factors (BAFs) of PFAs ranged from 91 to 380 L kg^?1 in wet weight after 25 d exposure; they increased with increasing perfluoroalkyl chain length and had a significant positive correlation with the n-octanol/water partition coefficients (log K_ow) of PFAs (p < 0.05). This indicated that the hydrophobicity of PFAs plays an important role in their bioaccumulation. The BAFs almost kept constant when the PFA concentrations in aqueous phase increased from 1 to 10 μg L^?1. Scenedesmus subspicatus, as the food of D. magna, did not significantly affect the bioaccumulation of PFAs by D. magna. Furthermore, the body burden of PFAs in the dead D. magna was 1.08–2.52 times higher than that in the living ones, inferring that the body surface sorption is a main uptake route of PFAs in D. magna. This study suggested that the bioaccumulation of PFAs in D. magna is mainly controlled by their partition between organisms and water; further research should be conducted to study the intrinsic mechanisms, especially the roles of protein and lipid in organisms.     

加强环境监测点位管理的思考——以江苏省“十二五”环境监测网络调整为例

基于江苏省"十二五"环境质量监测网络优化调整工作,指出监测点位设置和管理工作中存在的问题,讨论了点位优化调整的原则和思路,总结监测网络调整结果,并开展点位优化调整的成效分析,提出进一步优化监测网络设置的建议。     

寒旱区草原湖泊沉积物重金属地球化学基线构建——以达里诺尔湖为例

为了科学识别寒旱区典型草原湖泊——达里诺尔湖的沉积物重金属累积状况,在调查表层及柱状沉积物重金属含量的基础上,采用多种统计学方法构建了沉积物重金属地球化学基线,并针对构建结果进行了多方面比较分析.结果表明,Cr、Ni、Cu、Zn、As、Cd、Hg、Pb在表层及柱状沉积物中均呈正态分布或对数正态分布,其中,柱状沉积物中的重金属分布较表层更为集中,且As、Cd、Hg在近表层呈现较明显的增长趋势,表明存在一定的表层富集;使用参考元素法、相对累积频率法和迭代2倍标准差法构建的表层、柱状沉积物重金属基线值之间无显著差异（P<0.05）,综合考虑科学性,适用性,简便性,人为误差性等方面,可优先选取迭代2倍标准差法进行元素基线构建;研究构建的达里诺尔湖沉积物重金属基线值与所在区域的大尺度土壤背景值相比存在差异,且表层与柱状沉积物基线值也存在差异,考虑到达里诺尔湖流域人为干扰极小,使用研究区域的表层沉积物开展基线值构建,可为识别湖泊当前重金属富集状况和生态风险提供更为科学和准确的参考依据.研究结果可为类似的寒旱区草原湖泊沉积物重金属基线值构建提供理论依据.