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941.
Environmental Science and Pollution Research - In this study, an attempt was made to clarify the impact of substrates on the microbial fuel cell coupled with constructed wetland (CW-MFC) towards...  相似文献   
942.
Journal of Material Cycles and Waste Management - Eupatorium adenophorum (EA) has been spread widely in China and its increasing number has posed potential threats and damages to the ecosystem and...  相似文献   
943.
以浮萍(Lemna minor L.)为受试生物,通过研究不同浓度(0、0.6、1.8、5.4、16.2和48.6 mg·L-1)的4,4'-二氨基二苯基甲烷(4,4'-methylenedianiline,MDA)对浮萍生长、叶绿素含量、PSⅡ最大光化学效应(Fv/Fm)、质膜透性及超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性的影响,初步探讨MDA对水生植物浮萍的毒性作用.实验结果表明,在7d暴露时间下,MDA对浮萍叶片数、叶片数生长率、叶片干质量和叶面积都有显著的抑制作用,且抑制程度与MDA的浓度呈正相关.其对浮萍叶片数生长抑制的7d半数效应浓度(7 d-ECs0)为26.7 mg·L-1,95%置信限为22.3 ~ 32.1 mg·L-1;对浮萍叶片数产量抑制的7 d-EC50为0.62 mg-L-1,95%置信限为0.53~0.74 mg-L-1;对浮萍总叶面积及干质量产量抑制的7 d-EC50<0.6 mg·L-1.MDA处理导致浮萍总叶绿素含量和Fv/Fm下降,而浮萍质膜透性显著增加.低浓度MDA对浮萍SOD、POD和CAT酶活性无显著影响,但随着MDA浓度的升高SOD、POD和CAT酶活性显著升高,当MDA浓度达到48.6 mg· L-1时,抑制POD和CAT酶活性.以上结果表明,MDA能够直接损伤质膜,干扰叶绿体功能并抑制光合活性,而氧化损伤是质膜损伤引起的继发性应激,继而引起膜脂质过氧化,加剧质膜损伤,从而进一步抑制浮萍的生长.  相似文献   
944.
本文介绍了江西省九江"11·26"5.7级破坏性地震基本情况,对少震弱震地区发生破坏性地震后如何应对进行了分析,从加强地震序列跟踪监测,地震台站在新时期为政府、为社会服务,发挥其应有的作用三个方面提出了应对破坏性地震的对策.  相似文献   
945.
丁锶湲  王宁  倪丽丽  曾坚 《灾害学》2022,(1):171-177
以闽三角城市群为研究对象,创新水文SCS-CN算法与GIS耦合技术,计算出不同暴雨重现期(5 a,10 a,50 a一遇)下的淹没范围,构建闽三角城市群内涝淹没风险评估体系.通过地理探测器进一步探究淹没风险与社会生态系统空间分布规律,为闽三角城镇群的生态安全保障与可持续发展提供技术支撑.研究表明:闽三角城市群内涝淹没区...  相似文献   
946.
A case study of Dahu landslide from Linbao Henan in China was discussed in this paper. Based on various kinds of basic data, the 3D numerical model of a geological structure which possesses all kinds of information including the mechanical characteristics and the geometrical parameters of geological discontinuities were known from previous works. Thus, both the whole geological structure and all kinds of geological components involved in a slope can be visualized on computer, the complicated analysis and calculation can be then carried out easily and effectively. Firstly, the combination of 3D numerical model with the limit equilibrium analysis theory in slope stabilization can easily provide the present stability factor. Then according to monitoring data of the total station, the potential sliding trends are analyzed if landslides do not occur. Secondly, there are a number of uncertainties on the factors of multi-forms of disaster, such as, rainfall, earthquake, and mined-out area. The unascertained mathematics theory is applied to the stability comprehensive evaluation. It shows four landslide bodies get to be at unstable state if there are some inducements. Thirdly, sliding distance and movement scope were predicted if landslides occur. On the basis of the analysis above, the treatment of the landslide body called isolated method of culvert was proposed. It has solved the contradiction of landslide and mining radically, and provides important technical assurance for safety and sustainable development of mine.  相似文献   
947.
采用微波消解-原子荧光光谱法测定了垃圾焚烧飞灰中铅的含量。重点研究了铁氰化钾的用量以及加入盐酸羟胺对测定结果的影响。试验结果表明:加入铁氰化钾可以促进铅烷生成,盐酸羟胺可起到抑制干扰的作用。方法的检出限为0.39μg/L,回收率为83.6%~101.3%。  相似文献   
948.
Environmental Science and Pollution Research - Copper wastewater from industry is detrimental to plants and environment. There are some problems in the aspects of high efficiency and energy saving...  相似文献   
949.
950.
Anthropogenic activities are increasingly impacting the quality of urban surface water, particularly in regions undergoing intensive urbanization, such as Guangzhou of South China with a large urban stream network. To examine such impacts, we conducted field sampling on December 24, 2010, May 24, 2011, and August 28, 2011, representative of the low-, normal-, and high-flow periods, respectively. The first sampling was timed immediately after the closing of the 16th Asian Games (November 12–27, 2010) and the 10th Asian Para Games (December 12–19, 2010) held in Guangzhou. Assessments based on a pollution index method showed that the urban streams under investigation were extremely polluted, with direct discharge of untreated domestic sewage identified as the main pollution contributor. In addition, stream water quality around urban villages with high population densities was worse than that within business districts away from the urban villages. Pollution control measures implemented in preparation for the Asian Games were effective for urban streams within the business districts, but less effective for those adjacent to the urban villages. However, short-term efforts may not be able to achieve sustainable urban water quality improvements. In the case of Guangzhou, minimizing or even eliminating direct point-source inputs to the urban streams is perhaps the best option.  相似文献   
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