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21.
Toxicity and bioaccumulation of copper in three green microalgal species   总被引:13,自引:0,他引:13  
Yan H  Pan G 《Chemosphere》2002,49(5):471-476
The effective concentrations of copper on the inhibition of the growth of Scenedesmus obliquus, Chlorella pyrenoidosa and Closterium lunula at 96 h (96 h EC50) were determined to be 50, 68 and 200 microg/l, respectively. The low initial bioaccumulation of Cu by C. lunula was found to be responsible for its tolerance to Cu. The amount of Cu accumulated by all three microalgae reached the maximum value and decreased quickly after the peak followed by a slow decrease over the next 6 d. Bioaccumulation of Cu by C. lunula was directly proportional to the initial Cu concentration. After reaching the first peak after 1 d, the bioconcentration factor of Cu by microalgae declined to its minimum value during the exponential growth phase but increased in the stationary growth phase again. This indicates that desorption of Cu from microalgae was higher during the exponential growth phase but lower in the stationary growth phase. Smaller microalgae with low 96 h EC50 values are more efficient in removing Cu from wastewater.  相似文献   
22.
采掘诱发地震的成因及对策   总被引:14,自引:4,他引:14  
根据煤或岩体的赋存特征及采动后的受力特点,将采矿及掘进等工程进行过程中诱发的地震灾害分为三类,即完整煤岩体受压应力作用的失稳、顶底板受拉应力型地震及断层走滑受剪型诱发地震。文章在分别分析其成因的基础上,研究了采矿诱发三种类型地震的发生条件,提出了防治发生诱发地震的对策。  相似文献   
23.
长江中游不同潜育化土壤诊断指标探讨   总被引:4,自引:0,他引:4  
田间原位测定,室内分析和模拟试验的结果表明,长江中游垸田土壤潜育化过程中发生一系列物质变化,其中以活性还原物质量,Al2(SO4)3溶液提取的亚铁量和氧化还原电位三者变化最为显著。活性还原物质量和亚铁量与潜育化作用强度正相关,而氧化还原电位则呈负相关。  相似文献   
24.
Environmental Science and Pollution Research - In an effort to control dust pollution in open-air environments such as pit coal mines and coal transportation systems, a new dust suppressant with a...  相似文献   
25.
Environmental Science and Pollution Research - Microbial sulfate reduction, a vital mechanism for microorganisms living in anaerobic, sulfate-rich environments, is an essential aspect of the sulfur...  相似文献   
26.
Ji  Yanhu  Liu  Bin  Song  Jian  Pan  Rubing  Cheng  Jian  Wang  Heng  Su  Hong 《Environmental science and pollution research international》2022,29(30):45449-45460
Environmental Science and Pollution Research - The evidence on the health and economic impacts of air pollution with schizophrenia is scarce, especially in developing countries. In this...  相似文献   
27.
采用失重、电化学法研究了异喹啉季铵盐在 1mol/L盐酸溶液中对A3钢的缓蚀行为及吸附规律。实验表明 ,异喹啉季铵盐是一种阴、阳极混合型缓蚀剂 ,其缓蚀性能优良 ,在A3钢表面产生化学吸附 ,吸附过程为放热反应。  相似文献   
28.
针对感潮平原中心城区河道存在往复流现象带来的水质波动、生态岸线差、生态系统稳定性不足等问题,开展以基于生物屏障技术耦合水生动植物生态系统构建为主的全面系统的近自然生态修复集成技术及示范研究。注重源头削减和末端综合治理,通过集成构建河道水质稳定技术、海绵设施生态岸线、优化水生态系统措施等技术体系,并选取上海市中心城区典型河道进行示范应用及效果跟踪。结果表明,修复后河道水质和感官效果得到了极大提升,化学需氧量(COD)、氨氮、总磷、浊度/悬浮物(SS)各均值较未处理河道水质均值分别降低约23%、41%、35%、51%/52%,5大类抗生素除了洁霉素、克林霉素和磺胺吡啶外均未检出,河道水质从在地表水IV类水质上下波动稳定达到IV类(总氮指标除外)。  相似文献   
29.
Environmental Science and Pollution Research - In this work, various photocatalysts were synthesized with an impregnation-precipitation process to in situ decorate Ag-based nanoparticles (NPs,...  相似文献   
30.
Quantifying greenhouse gas (GHG) emissions from wetland ecosystems is a relatively new issue in global climate change studies. China has approximately 22% of the world's rice paddies and 38% of the world's rice production, which are crucial to accurately estimate the global warming potential (GWP) at regional scale. This paper reports an application of a biogeochemical model (DeNitrification and DeComposition or DNDC) for quantifying GWP from rice fields in the Tai-Lake region of China. For this application, DNDC is linked to a 1:50,000 soil database, which was derived from 1107 paddy soil profiles compiled during the Second National Soil Survey of China in the 1980–1990s. The simulated results show that the 2.34 Mha of paddy soil cultivated in rice–wheat rotation in the Tai-Lake region emitted about ?1.48 Tg C, 0.84 Tg N and 5.67 Tg C as CO2, N2O, and CH4 respectively, with a cumulative GWP of 565 Tg CO2 equivalent from 1982 to 2000. As for soil subgroups, the highest GWP (26,900 kg CO2 equivalent ha?1 yr?1) was linked to gleyed paddy soils accounting for about 4.4% of the total area of paddy soils. The lowest GWP (5370 kg CO2 equivalent ha?1 yr?1) was associated with submergenic paddy soils accounting for about 0.32% of the total area of paddy soils. The most common soil in the area was hydromorphic paddy soils, which accounted for about 53% of the total area of paddy soils with a GWP of 12,300 kg CO2 equivalent ha?1 yr?1. On a regional basis, the annual averaged GWP in the polder, Tai-Lake plain, and alluvial plain soil regions was distinctly higher than that in the low mountainous and Hilly soil regions. As for administrative areas, the average annual GWP of counties in Shanghai city was high. Conversely, the average annual GWP of counties in Jiangsu province was low. The high variability in soil properties throughout the Tai-Lake region is important and affects the net greenhouse gas emissions. Therefore, the use of detailed soil data sets with high-resolution digital soil maps is essential to improve the accuracy of GWP estimates with process-based models at regional and national scales.  相似文献   
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