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831.
832.
833.
以钦江青年水闸断面为研究对象,采用2001年~2009年的水质监测数据,计算了污染最重的氨氮、溶解氧和石油类3项污染因子的污染指数(Pi)及断面的综合污染指数(Pj)。通过分析得出,钦江青年水闸断面氨氮污染指数在2004年-2009年基本维持平缓,溶解氧和石油类污染指数在2001年-2006年期间上升幅度比较大,在2007年-2009年,逐步下降并且持续平缓。水质综合污染指数在2003年和2006年分别达到了5.440、4.940,断面水质属轻污染级别,2007年-2009年青年水闸断面的综合污染指数基本保持稳定(<4),河流水质的年际变化不大。 相似文献
834.
Zi Wu Zhi Li Li Zeng Ling Shao Hansong Tang Qing Yang Guoqian Chen 《Frontiers of Environmental Science & Engineering in China》2011,5(4):597-603
Distinct from the case with width-dominated shallow wetland flows, the longitudinal evolution of contaminant concentration
in the most-typical pattern of wetland as dominated by free-water-surface-effect is characterized by a multi-scale analysis
in the present study. An environmental dispersion model for the evolution of the mean concentration is deduced as an extension
of Taylor’s classical formulation by Mei’s multi-scale analysis. Corresponding environmental dispersivity is found identical
to that determined by the method of concentration moments. 相似文献
835.
Huan He Bo Tang Cheng Sun Shaogui Yang Weijuan Zheng Zichun Hua 《Frontiers of Environmental Science & Engineering in China》2011,5(3):409-416
High-affinity and specific monoclonal antibodies against cadmium-ethylene diamine tetraacetic acid (EDTA) complex have been
produced using the hybridoma technique. A hapten was synthesized and characterized by Fourier Transform Infrared Spectroscopy
(FT-IR) and UV-Vis. Competitive enzyme-linked immunosorbent assay (ELISA) for quantitative detection of cadmium in aqueous
sample was developed. The monoclonal antibody with high level of binding affinity for Cd-IEDTA-BSA and high specificity for
soluble Cd-EDTA complex showed less than 0.99% cross-reactivity with other 11 metals. The limit of detection was 0.10 μg·L−1, and the effective linear range was 10−1–103 μg·L−1. The intra- and inter-assay coefficient variations were 1.5%–6.3% and 3.2%–7.4%, respectively. The spike recovery in different
water samples were between 98.5% and 110.3%. The detection limit of this assay was well below the allowable concentration
of cadmium (3 μg·L−1), and the working range was wider than that of other methods which showed the range of 2.19–86.38 and 0–103 μg·L−1. The competitive ELISA established in this paper was sensitive and accurate in the screening of cadmium in aqueous samples.
The results will lay a solid foundation for construction of an immunoassay kit for cadmium. 相似文献
836.
Influence of influent on anaerobic ammonium oxidation in an Expanded Granular Sludge Bed-Biological Aerated Filter integrated system 总被引:1,自引:0,他引:1
Daijun Zhang Cui Bai Ting Tang Qing Yang 《Frontiers of Environmental Science & Engineering in China》2011,5(2):291-297
Shortcut nitrification-denitrification, anaerobic ammonium oxidation (ANAMMOX), and methanogenesis have been successfully
coupled in an Expanded Granular Sludge Bed-Biological Aerated Filter (EGSB-BAF) integrated system. As fed different synthetic
wastewater with chemical oxygen demand (COD) of 300–1200 mg·L−1 and NH4+-N of 30–120 mg·L−1 at the outer recycle ratio of 200%, the influence of influent on ANAMMOX in the integrated system was investigated in this
paper. The experimental results showed that higher COD concentration caused an increase in denitrification and methanogenesis
but a decrease in ANAMMOX; however, when an influent with the low concentration of COD was used, the opposite changes could
be observed. Higher influent NH4+-N concentration favored ANAMMOX when the COD concentration of influent was fixed. Therefore, low COD =NH4+-N ratio would decrease competition for nitrite between ANAMMOX and denitrification, which was favorable for reducing the
negative effect of organic COD on ANAMMOX. The good performance of the integrated system indicated that the bacterial community
of denitrification, ANAMMOX, and methanogenesis could be dynamically maintained in the sludge of EGSB reactor for a certain
range of influent. 相似文献
837.
锅炉灰渣综合利用就是利用灰渣烧结砖代替粘土实心砖,以资源的高效和循环利用,促进经济、社会的可持续发展。以宁安化工名锅炉有限公司锅炉灰渣。 相似文献
838.
高分辨率监测岩溶地下水NO-3的动态变化及对外界环境的响应 总被引:8,自引:8,他引:0
为深入揭示岩溶地下水文系统对外界环境的响应,利用多指标高分辨率在线监测技术对受农业活动影响的重庆青木关地下河水文地球化学变化进行研究.主要的高分辨率监测指标包括水位、电导率(EC)、pH值、降雨和NO 3-.在观测的6场降雨内,地下河水化学特征快速地反映着外界环境的变化.研究区地下水pH值的变化主要受到酸雨的影响,在降雨后都表现出明显的下降趋势,但在农业废水进入地下河系统后,它的变化受到两者的共同影响.EC受到雨水化学、稀释效应及农业活动废水的影响.NO 3-主要是农业活动的产物,受雨水水化学特征的影响较小,它的变化主要受农业废水及稀释效应的影响.在R1降雨影响下,水位上升,EC和NO 3-总体呈相反的快速变化过程而pH值的变化主要受酸雨影响而下降.在R2、R3、R4和R6降雨期,水位受降雨影响而快速的变化,pH值受酸雨影响而下降,EC和NO 3-受稀释效应影响也下降.但随着农业活动废水进入地下河系统,EC和NO 3-浓度在最快5 h最慢仅27 h的时段内同步地急剧升高,pH值也受影响而加速下降.在R5大暴雨期,水位急剧上升,EC和NO 3-受稀释效应影响而急剧下降,pH值先受到酸雨影响而下降,后由于稀释效应... 相似文献
839.
840.
Whether plant coexistence can reduce the impacts of lead (Pb) on crops in agroecosystems has not been well understood. We conducted a factorial experiment to investigate the effects of weeds coexisting with maize (Zea mays L.) on Pb accumulation in maize and soil microbes at two Pb levels (ambient and 300 mg/kg). Elevated Pb tended to increase the Pb concentration in maize and decreased soil microbial activity (indicated by the average well color development, AWCD), functional group diversity, as well as arbuscular mycorrhizal (AM) colonization and vesicle number of maize. Compared to the monoculture, weeds coexisting with maize reduced the Pb concentrations in the root, leaf, sheath and stem of maize at both seedling and mature stages. In maize-weed mixtures, soil microbial activity and functional group diversity tended to increase for both Pb treatments relative to the monoculture. Furthermore, principal component analysis revealed that the soil microbial community structure changed with the introduction of weeds. The highest Pb accumulation in weeds occurred for the elevated Pb treatment in a three species mixture. The results suggest that multiple plant species coexistence could reduce lead accumulation in crop plants and alleviate the negative impacts on soil microbes in polluted land, thereby highlighting the significance of plant diversity in agroecosystems. 相似文献