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881.
通过构建光合藻微生物燃料电池(PAMFC),研究了分别以乙酸钠或葡萄糖作为唯一电子供体时,对PAMFC的产电性能及其中小球藻生长的影响。结果表明,在外电阻为1 000 Ω时,以乙酸钠为电子供体的PAMFC最大输出电压是285 mV、最大输出功率为3.42 mW/m2;以葡萄糖为电子供体的PAMFC最大输出电压是247 mV、最大输出功率为2.68 mW/m2。同时,分别以乙酸钠或葡萄糖为电子供体的PAMFC中小球藻生长所达到的生物量分别是1.8 g/L和1.26 g/L,而对照组中的小球藻生物量仅为0.83 g/L。简单电子供体的电池性能优于复杂电子供体,同时更能促进PAMFC中阴极光合藻生长,使电池阴极得以固定更多阳极所排放的二氧化碳。  相似文献   
882.
王群  杨志超  徐贺 《环境工程学报》2017,11(4):2113-2118
考察了重碳酸根离子(HCO3-)、磷酸根离子(PO43-)、硫酸根离子(SO42-)和硝酸根离子(NO3-)等自然水体中常见的无机阴离子对非均相催化臭氧氧化邻苯二甲酸(PA)的影响。结果表明,能够捕获羟基自由基(HO·)的HCO3-对羟基氧化铁催化臭氧氧化体系影响很大,会明显抑制该体系对PA的降解,而对氧化铈催化臭氧氧化体系基本没有影响。PO43-和SO42-对2个体系中PA的降解均有很大的抑制效果,而NO3-对此影响甚少。从这些无机阴离子的影响可以侧面证明羟基氧化铁催化臭氧氧化遵循羟基自由基机理,而氧化铈催化臭氧氧化PA主要依靠络合作用。  相似文献   
883.
As a special ecosystem, an urban forest park, which is different from a regular “forest park”, is one of the key elements involved in improving the urban ecological environment and promoting the sustainable development of a city. The “urban forest park” can also significantly improve living conditions by acting as a greenbelt. The Chengdu Longquan Mountain Urban Forest Park is a rare mountain urban forest park located in the center of the city. This “urban forest park” not only provides more ecological products and maintains ecological security but also meets the growing needs of people for food, environmental quality, and spirituality. To comprehensively assess the ecological value of the Chengdu Longquan Mountain Urban Forest Park, this study used the literature analogy and questionnaire survey methods to establish a targeted ecosystem service assessment system in this study area. In addition, combined with the hierarchical analysis method, the indicator system was tested, and the specific evaluation index was determined. In the Longquan Mountain Urban Forest Park Ecosystem Service Value Index System, three first-level indicators, such as ecological material products (with a weight of 0.412 6), ecological regulation (0.327 5), and dwelling culture (0.259 9); eight secondary indicators, such as product production (0.206 3), resource supply (0.206 3), and biodiversity (0.194 4); and twenty-three tertiary indicators, such as air negative oxygen ion (0.154 7), habitat quality (0.095 9), and ecological health benefit (0.075 5), were identified. From the weights of the first and second indicators, it was clear that the supply of ecological material products is the main service function in the Longquan Mountain Urban Forest Park ecosystem. Moreover, from the weights of the third indicator, the public’s cognition and concept of the ecosystem service value of the “urban forest park” gradually shifted from the supply service of products and resources to cultural services. In summary, the ecosystem service value assessment system designed for the Longquan Mountain Urban Forest Park in this study has certain feasibility and extensibility that lays a theoretical foundation for the scientific assessment of ecological value and ecological value realization mechanism for other “forest parks” worldwide. © 2022 Authors. All rights reserved.  相似文献   
884.
单甲脒农药对鱼脑胆碱酯酶活性的影响   总被引:8,自引:0,他引:8  
金鱼,鲤鱼在实验室驯化4-7d,其脑胆碱酯酶活力在显著水平为P≤0.05时,不同组的金鱼,鲤鱼无显著差异。离体实验条件下,单甲脒农药对金鱼,鲤鱼的半抑制浓度分别为125.9mg.l^-1和25.7mg.l^-1。DMA农药对鲤鱼的作用大于对金鱼的作用。  相似文献   
885.
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   
886.
太湖生态修复治理工程   总被引:8,自引:0,他引:8  
太湖是我国第三大淡水湖泊 ,也是流域的重要水体。近年来 ,随着人口的增长 ,经济高速发展 ,人为社会经济活动影响 ,水资源系统受到很大冲击 ,水质变劣 ,湖体营养过程加剧 ,生态环境受到明显损害 ,制约了流域社会经济的可持续发展。要实现流域水资源的可持续利用 ,必须加快水污染综合治理。除陆域实施严格的达标治理、河网水质调控 ,农业面源及生活污水治理外 ,太湖湖体生态修复和富营养化治理已为当务之急。目前应尽早实施 :①太湖重污染区底泥的生态疏浚 ,减少底泥释放二次污染。②利用浮床陆生植物治理太湖典型富营养化水域 ,利用生物吸收、降解 ,继而富集营养盐 ,净化水质。③建立环湖湿地保护带。④恢复和重建湖滨带水生植被 ,实现长效生态管理和调控。⑤生态渔业工程 ,有效控制过度养殖 ,恢复湖泊生态良性循环。⑥藻类采集和资源化再利用。⑦强化流域  相似文献   
887.
ABSTRACT

Coastal cities represented by Ningbo are directly or indirectly affected by typhoons each year. By analyzing the past three typical typhoons landing in Ningbo from 2013 to 2016, it was found that before and after the typhoon transit, reservoir and water treatment plant would be made by the destructive impact, including the increasing water level, water volume in a short time, and the deteriorating water quality. Among those, the water quality caused by typhoons increased the water treatment process load, the amount of water purification agents increased significantly, and the emergency response put a great pressure on the inventory of water plants. Based on the statistics and analysis of the basic parameters of the reservoir and water treatment plant during the typhoon season, the emergency management of the typhoon was divided into three situations, namely, pre-typhoon, typhoon period and post-typhoon. Thus, it is effective for the relevant practitioners of the reservoir and water plant to ensure the safe water supply during typhoon season.  相似文献   
888.
何珩 《四川环境》1997,16(1):30-33
用投放质控标准样的方法来选择若干校准曲线,对这些标准曲线的截距a、斜率b的进行总体参数进行区间估计。在实际工作中根据估计出的置信区间便可控制和检验监测所做校准曲线的质量,从而间接推断同期环境监测的质量。  相似文献   
889.

Background, Aim and Scope  

The impact of air pollution on school children’s health is currently one of the key foci of international and national agencies. Of particular concern are ultrafine particles which are emitted in large quantities, contain large concentrations of toxins and are deposited deeply in the respiratory tract.  相似文献   
890.
淮南大通浅覆盖岩溶区塌陷分布及土地利用可行性   总被引:1,自引:0,他引:1  
通过地质调查、钻探、物探等方法对淮南大通浅覆盖岩溶区岩溶塌陷的分布特征及诱因进行了分析,结果表明,大通浅覆盖岩溶区岩溶塌陷主要分布于下伏奥陶系马家沟组地层之上,以及构造发育区和松散层粉土含量较高区,岩溶塌陷主要受岩石溶蚀程度、强烈地下水动力条件及松散层厚度、成分等控制。结合岩溶塌陷发育特征及场地具体条件,探讨了大通浅覆盖型岩溶区土地利用的可行性,为土地综合开发利用提供参考。  相似文献   
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