Removal,distribution and plant uptake of perfluorooctane sulfonate (PFOS) in a simulated constructed wetland system

• PFOS was removed by soil adsorption and plant uptake in the VFCW. • Uptake of PFOS by E. crassipes was more than that of C. alternifolius. • PFOS in wastewater can inhibit the removal of nutrients. • Dosing with PFOS changed the soil microbial community in the VFCW. A vertical-flow constructed wetland (VFCW) was used to treat simulated domestic sewage containing perfluorooctane sulfonate (PFOS). The removal rate of PFOS in the domestic sewage was 93%–98%, through soil adsorption and plant uptake, suggesting that VFCWs can remove PFOS efficiently from wastewater. The removal of PFOS in the VFCW was dependent on soil adsorption and plant uptake; moreover, the percentage of soil adsorption was 61%–89%, and was higher than that of the plants uptake (5%–31%). The absorption capacity of Eichhornia crassipes (E. crassipes) (1186.71 mg/kg) was higher than that of Cyperus alternifolius (C. alternifolius) (162.77 mg/kg) under 10 mg/L PFOS, and the transfer factor of PFOS in E. crassipes and C. alternifolius was 0.04 and 0.58, respectively, indicating that PFOS is not easily translocated to leaves from roots of wetland plants; moreover, uptake of PFOS by E. crassipes was more than that of C. alternifolius because the biomass of E. crassipes was more than that of C. alternifolius and the roots of E. crassipes can take up PFOS directly from wastewater while C. alternifolius needs to do so via its roots in the soil. The concentration of 10 mg/L PFOS had an obvious inhibitory effect on the removal rate of total nitrogen, total phosphorus, chemical oxygen demand, and ammonia nitrogen in the VFCW, which decreased by 15%, 10%, 10% and 12%, respectively. Dosing with PFOS in the wastewater reduced the bacterial richness but increased the diversity in soil because PFOS stimulated the growth of PFOS-tolerant strains.     

铝的水解聚合形态分析方法研究

本文主要探讨了铝的水解聚合形态的两种测定方法，即Ａ１－Ｆｅｒｒｏｎ逐时络合比色法和＾２７Ａ１ ＮＭＲ核磁共振法。扼要地说明了Ａ１－Ｆｅｒｒｏｎ逐时络合比色法中不同比色－缓冲的配制及其测定结果，以及＾２７Ａ１ ＮＭＲ法中大、小管测量方法及其测定结果。最后对这两种铝的水解聚合形态分析方法的相关性作了对比。     

纳米Fe2O3-TiO2催化剂的制备及其对甲基橙的降解

以钛酸四丁酯为主要原料、冰醋酸为抑制剂,采用溶胶-凝胶法制备纳米Fe2O3-TiO2复合催化剂,并用X射线衍射（XRD）、透射电子显微镜（TEM）和荧光光谱（FS）分析了催化剂的晶体结构、形貌和光谱特征。以甲基橙溶液为处理对象,在可见光下研究了不同n（Fe2O3）：n（TiO2）的催化剂的光催化活性,并初步研究了荧光强度与催化剂的光催化活性之问的关系。研究结果表明,n（Fe2O3）：n（TiO2）为0．10％的催化剂的光催化活性最佳,光照4h后甲基橙的去除率达99．8％,且荧光强度与光催化活性呈正相关性。     

湿式氧化法预处理甲基氯化物废水

研究了反应时间，进水pH，反应温度以及氧分压对湿式氧化法预处理甲基氯化物生产废水的影响。在不调节废水的pH，反应温度180℃，氧分压1.5MPa，反应时间60min的最佳操作条件下，COD，有机磷，有机硫的去除率分别达到68.5%,65%,88%,出水的BOD5/COD由0.107提高至0.36。预处理后废水的厌氧可生化性得到很大的改善，COD的去除率提高20%-30%左右，产甲烷量增加1.6-2.1倍。     

钡渣用于三相流化床烟气脱硫

提出了在三相流化床内用钡渣进行烟气脱硫的方法。分析了钡渣湿法脱硫原理，并进行了工艺改进实验，对两种不同溶渣方式工艺进行了静态和动态模拟实验，考察了两种方式的离子浓度和吸收容量等因素。实验表明，将渣先和水混合再用脱硫废水调整水质、脱硫塔进水pH在7．5左右时有利于系统的稳定运行。当液气比为2．88、气速为9．5m／s时，脱硫效率可以达到85％以上。这种方法可大大降低脱硫成本，实现以废治废。     

从醇/酮装置酸性废水中回收甲酸

采用共沸—分馏组合法从环己醇和环己酮生产装置产生的酸性废水中回收甲酸,确定了适宜挟带剂的种类及加入量。采用共沸—分馏组合法可获得甲酸质量分数达80%以上的甲酸水溶液,甲酸回收率达70%以上。回收甲酸后,酸性废水的COD由1.0×105~1.6×105m g/L降至500m g/L以下,COD去除率达到99%以上。     

Sorbents for CO2 capture from high carbon fly ashes

Fly ashes with high-unburned-carbon content, referred to as fly ash carbons, are an increasing problem for the utility industry, since they cannot be marketed as a cement extender and, therefore, have to be disposed. Previous work has explored the potential development of amine-enriched fly ash carbons for CO(2) capture. However, their performance was lower than that of commercially available sorbents, probably because the samples investigated were not activated prior to impregnation and, therefore, had a very low surface area. Accordingly, the work described here focuses on the development of activated fly ash derived sorbents for CO(2) capture. The samples were steam activated at 850 degrees C, resulting in a significant increase of the surface area (1075m(2)/g). The activated samples were impregnated with different amine compounds, and the resultant samples were tested for CO(2) capture at different temperatures. The CO(2) adsorption of the parent and activated samples is typical of a physical adsorption process. The impregnation process results in a decrease of the surface areas, indicating a blocking of the porosity. The highest adsorption capacity at 30 and 70 degrees C for the amine impregnated activated carbons was probably due to a combination of physical adsorption inherent from the parent sample and chemical adsorption of the loaded amine groups. The CO(2) adsorption capacities for the activated amine impregnated samples are higher than those previously published for fly ash carbons without activation (68.6 vs. 45mg CO(2)/g sorbent).     

微波-改性活性炭-Fenton试剂氧化法降解水中2,4-二氯酚

以经Fe2（SO4）3溶液浸渍改性的活性炭作催化剂、Fenton试剂作氧化剂,采用微波-改性活性炭-Fenton试剂氧化法降解水中的2,4-二氯酚。考察了改性活性炭加入量、H2O2与Fe^2＋摩尔比、Fenton试剂加入量、微波功率和2,4-二氯酚溶液初始pH对2,4-二氯酚降解效果的影响。在改性活性炭加入量1．0g／L、n（H2O2）：n（Fe^2＋）=16．7（H2O2加入量6．0mmol／L、Fe^2＋加入量0．36mmol／L）、Fenton试剂加入量为6．36mmol／L、微波功率600W、微波辐射时间10min、2,4-二氯酚溶液初始pH为6．0的条件下,2,4-二氯酚降解率和TOC去除率分别可达98．7％和84．0％。     

Paired assistance policy and recovery from the 2008 Wenchuan earthquake: a network perspective

The role of the paired assistance policy (PAP) in facilitating recovery after the Wenchuan earthquake in China on 12 May 2008 is best analysed from a network perspective. This paper makes five assumptions to explore the relationship, and then draws on three additional cases to examine them. The key findings support all five assumptions. First, the interactions of authority compliance initiated the PAP, and second, the interactions of resource input significantly contributed to rapid reconstruction following the earthquake. Third, the interactions of knowledge transfer supported social system recovery, and fourth, the interactions of benefit reciprocity laid the foundation for sustainable recovery. Fifth, by contrast, the interactions of performance comparison caused suboptimal overfunding of particular public infrastructure projects and reduced local self‐reliance to some extent. Finally, suggestions are made to improve the policy implications of extending the use of the PAP in other administrative contexts. The PAP could become an even more important policy device in the future.     

Control strategies for disinfection byproducts by ion exchange resin,nanofiltration and their sequential combination

● Effects of AER adsorption and NF on DBP precursors, DBPs, and TOX were examined. ● A treatment approach of resin adsorption followed by nanofiltration was developed. ● Both DOC and Br⁻ could be effectively removed by the sequential approach. ● DBPs, TOX, and cytotoxicity were significantly reduced by the sequential approach. Disinfection byproducts (DBPs) are emerging pollutants in drinking water with high health risks. Precursor reduction before disinfection is an effective strategy to control the formation of DBPs. In this study, three types of anion exchange resins (AERs) and two types of nanofiltration (NF) membranes were tested for their control effects on DBP precursors, DBPs, and total organic halogen (TOX). The results showed that, for AER adsorption, the removal efficiencies of DBP precursors, DBPs, and TOX increased with the increase of resin dose, and the strong basic macroporous anion exchange resin (M500MB) had the highest removal efficiencies. For NF, the highest removal efficiencies were achieved at an operating pressure of 4 bar, and the membrane (NF90) with a smaller molecular weight cut-off, had a better control efficiency. However, AER adsorption was inefficient in removing dissolved organic carbon (DOC); NF was inefficient in removing Br⁻ resulting in insufficient control of Br-DBPs. Accordingly, a sequential approach of AER (M500MB) adsorption followed by NF (NF90) was developed to enhance the control efficiency of DBPs. Compared with single AER adsorption and single NF, the sequential approach further increased the removal efficiencies of DOC by 19.4%–101.9%, coupled with the high Br⁻ removal efficiency of 92%, and thus improved the reduction of cyclic DBPs and TOX by 3.5%–4.9%, and 2.4%–8.4%, respectively; the sequential approach also reduced the cytotoxicity of the water sample by 66.4%.