基于IKONOS影像的城市住宅区中水回用空间分布估算

中水回用是解决城市水资源短缺和水环境污染问题的有效途径。开展分散式中水可行性研究,需要考虑中水原水与回用需求的数量、空间分布及平衡关系。论文以南京市住宅区为例,探索了基于IKONOS高分辨率遥感影像分类,估算中水回用空间分布的方法。通过引入单位面积用水定额,将遥感和GIS 分析得到的用地信息与中水原水产量和回用需求关联起来,计算了研究区域中27 个地块的中水原水产量和回用需求量,并分析了两者在空间上的水量平衡关系。结果表明,研究区域存在较大的中水原水供给潜力3.52 L/（m²·d）和较大的利用需求5.37 L/（m²·d）。住宅小区的单位面积原水产量与其建筑容积率成正比;以中高层住宅区为主的地区,中水原水产量能够基本满足本地区的中水回用需求。因此,在这些地区建立分散式污水处理系统,可减少废污水排放,节约自来水取用量,提高水资源利用率。     

基于HPR在线监测控制SBR曝气历时实现短程脱氮

应用新型自动呼吸-滴定测量仪在线测量pH值、HPR等信号,进行了在SBR内实现短程脱氮的研究.采用SBR处理人工合成废水,COD和NH4+-N浓度分别为360,40mg/L,温度稳定在20℃,DO低于2mg/L,基于HPR在线监测控制SBR曝气历时.运行约60d后,亚硝酸盐积累率达到88%,COD和NH4+-N去除率均在90%以上,稳定实现了短程硝化反硝化.应用HPR估计硝化过程的NH4+-N浓度发现,NH4+-N实测值与基于HPR的计算值间存在良好的线性关系,相关系数为0.9722;计算值整体低于实测值,主要是由曝气初期的滴定启动滞后所致.     

烟草对砷的吸收累积特征及其健康风险研究

以福建省主栽烟草品种翠碧1号、K326和云烟87为材料,在外源砷添加量为0、10、20、40、70和100 mg·kg~(-1)的土壤中进行盆栽试验,探讨砷对烟草的毒害效应以及砷在土壤-烟草体系中的迁移累积特征,并对植烟土壤中砷的安全临界值进行计算。结果表明,在砷毒害下,烟草生长受到抑制,且烟草根系生长受抑制程度最强。随着砷添加量的增加,土壤中有效砷含量和烟草各部位砷含量均显著提高(P 0.05),砷在根系中的含量最高,在茎中的含量最低。砷处理下各部位间的转移系数表现为TF_((茎-叶)) TF_((土-根)) TF_((根-茎)),且外源砷的增加促进砷从茎到叶片中转移。38.28%～74.37%的砷富集在烟草根部,上部叶中砷的富集量最少(4.61%～11.7%),且所研究的3个烟草品种中翠碧1号对砷的富集能力最强。根据通过吸烟进入人体砷的限量以及土壤有效砷含量与烟草中部叶砷含量的回归模型,推算出翠碧1号、K326和云烟87的植烟土壤有效砷的安全临界值分别为14.17、14.31和11.86 mg·kg~(-1)(磷酸二氢钠浸提)。并将福建省植烟土壤有效砷的安全临界值拟定为11.86 mg·kg~(-1)(磷酸二氢钠浸提)。本研究结果为福建省烟草安全生产提供一定技术指导。     

锅炉电除尘器效率下降原因及改进对策

在对影响锅炉电除尘器效率的因素进行了较为全面分析的基础上,对电除尘器的各有关环节和除尘机理之间的内在联系进行了深入的分析,讨论了进一步提高电除尘器除尘效率的相关对策和建议。     

过硫酸铵含铜废液预处理工艺改造

采用离子交换工艺对过硫酸铵含铜废液预处理原有工艺进行改造,改造后降低了废液预处理成本,减少二次污染,提高铜资源的回收率,达到综合利用的目的,具有很高的环境效益及经济效益。     

基于BSCCO-CC的准各项同性超导股线电流特性研究

设计了一种基于铋锶钙铜氧化物高温超导带材(BSCCO-CC)的方形四分准各向同性超导股线结构,研究其电流特性的主要参数,包括自场临界电流、n值和外场临界电流及它们随外加磁场的变化关系。随后利用电磁仿真软件Ansoft Maxwell建模仿真,得到超导股线自场下的磁场分布,并结合Matlab软件进行计算,得到超导股线自场临界电流值、n值和外场临界电流值,并对外场电流值与外加磁场的变化关系进行分析得到相关结论。仿真验证本文所设计的BSCCO-CC方形四分准各向同性超导股线结构的合理性,证明该结构具备优良的电流特性。     

Mechanisms for simultaneous ozonation of sulfamethoxazole and natural organic matters in secondary effluent from sewage treatment plant

• SMX was mainly degraded by hydrolysis, isoxazole oxidation and double-bond addition. • Isoxazole oxidation and bond addition products were formed by direct ozonation. • Hydroxylated products were produced by indirect oxidation. • NOM mainly affected the degradation of SMX by consuming ^•OH rather than O₃. • Inhibitory effect of NOM on SMX removal was related to the components’ aromaticity. Sulfamethoxazole (SMX) is commonly detected in wastewater and cannot be completely decomposed during conventional treatment processes. Ozone (O₃) is often used in water treatment. This study explored the influence of natural organic matters (NOM) in secondary effluent of a sewage treatment plant on the ozonation pathways of SMX. The changes in NOM components during ozonation were also analyzed. SMX was primarily degraded by hydrolysis, isoxazole-ring opening, and double-bond addition, whereas hydroxylation was not the principal route given the low maximum abundances of the hydroxylated products, with m/z of 269 and 287. The hydroxylation process occurred mainly through indirect oxidation because the maximum abundances of the products reduced by about 70% after the radical quencher was added, whereas isoxazole-ring opening and double-bond addition processes mainly depended on direct oxidation, which was unaffected by the quencher. NOM mainly affected the degradation of micropollutants by consuming ^•OH rather than O₃ molecules, resulting in the 63%–85% decrease in indirect oxidation products. The NOM in the effluent were also degraded simultaneously during ozonation, and the components with larger aromaticity were more likely degraded through direct oxidation. The dependences of the three main components of NOM in the effluent on indirect oxidation followed the sequence: humic-like substances>fluvic-like substances>protein-like substances. This study reveals the ozonation mechanism of SMX in secondary effluent and provides a theoretical basis for the control of SMX and its degradation products in actual water treatment.     

面向人体暴露评价的植物中抗生素分析进展

抗生素通过动物粪便或生物固体的施用、再生水灌溉进入农业土壤后可以被蔬菜和粮食作物吸收,从而造成人体的被动暴露。为了评估抗生素对人体暴露的健康风险,需要基于植物样品,发展灵敏、稳定且针对性强的分析方法。本文综述了植物样品中抗生素残留分析的研究进展,重点介绍了样品提取、净化等前处理方法及其仪器分析方法,并对植物样品中抗生素分析的研究方向进行了展望。     

Industrial land expansion in rural China threatens environmental securities

• China’s rural industrial land (RIL) area quadrupled from 1990 to 2015. • RIL expansion cost 9% of China’s crop production and threatened human/ecosystem safety. • The underprivileged population bears a disproportionally large share of the risks. China’s rural industrialization has been a major driver for its rapid economic growth during the recent decades, but its myriad environmental risks are yet to be fully understood. Based on a comprehensive national land-use data set, our study shows that the area of China’s rural industrial land (RIL) quadrupled during 1990–2015, reaching 39000 km² in 2015, comparable to urbanization in magnitude but with a much greater degree of landscape fragmentation which implies stronger ecological and environmental impacts. About 91% of the protected areas in the central China were within 50 km from rural industrial land, thus exposed to industrial disturbances. Accelerated rural industrial land expansion, particularly in regions under high geo-hazard risks, led to dramatically increased environmental risks, threatening the safety and health of both rural industrial workers and residents. Moreover, negative effects from rural industrial land expansion could partially offset the crop production growth in recent decades. The underprivileged rural population in the west bears a disproportionally large share of the increased environmental risks. China urgently needs to design and implement sustainable policies to restrict and reshape its rural industrialization. This study aims to inspire policy makers and researchers to rethink the current model of industrial expansion and improve rural industrial land planning, which is important for achieving the sustainable development goals of China.     

剧毒卡尔藻对海洋生物毒性及机制的初步研究

剧毒卡尔藻(Karlodinium veneficum)是一种有毒甲藻,近年在我国沿海已经爆发过藻华,值得关注。本文研究了剧毒卡尔藻对不同粒径、不同营养级的几种海洋生物褶皱臂尾轮虫(Brachionus plicatilis)、卤虫(Artemia salina)、黑褐新糠虾(Neomysis awatschensis)、中华哲水蚤(Calanus sinicus)存活及摄食的影响。研究发现:该藻对轮虫、卤虫存活影响较大,对黑褐新糠虾存活的影响较小,对中华哲水蚤存活几乎无影响。48 h,对轮虫的半数致死密度LC503400 cells/mL;96 h对卤虫的半数致死密度为LC504800 cells/mL;对黑褐新糠虾的半数致死密度为LC5089000 cells/mL;在89000 cells/mL的藻密度下,中华哲水蚤存活率约为80%。该藻不同组分对实验生物的影响是不同的,细胞破碎液对轮虫、黑褐新糠虾的影响最大;细胞外液对卤虫的影响最大。该藻对生物的摄食影响则发现,24 h内,轮虫、卤虫、中华哲水蚤均摄食该藻,且3种生物的摄食率随着藻密度增高而增加。可见,剧毒卡尔藻对不同生物的影响不同,其现场藻密度一般可达到104cells/mL,对轮虫、卤虫存活影响很大;该藻对生物有不同的致毒机制和致毒途径。结果表明:该藻藻华爆发,可能会对浮游生态系统产生较大影响;研究有害藻对不同粒径、不同营养级生物的影响,才可以更全面的反映出它对生态系统的危害。