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为了筛选对Cr(Ⅵ)净化效果好的湿地基质,通过小试实验,研究了以水稻土、红土、沙子、泥炭、硅藻土、粉煤灰为基质的李氏禾(Leersia hexandra Swartz)湿地系统对Cr(Ⅵ)的净化效果,并比较了6种基质的湿地系统中pH、Eh、有机质含量、微生物数量和李氏禾生物量的差异,结果表明,以泥炭和水稻土为基质的湿地系统的Cr(Ⅵ)净化效果显著好于其他基质的湿地系统,并且这2种基质湿地系统中李氏禾的生物量显著高于其他4种基质的湿地系统(p0.05)。当Cr(Ⅵ)进水质量浓度为5 mg/L时,泥炭、水稻土人工湿地对Cr(Ⅵ)的平均去除率可达到99.94%和99.54%。6种基质的pH有较大差异,但总体而言,p H较高的硅藻土和粉煤灰不利于Cr(Ⅵ)的还原去除。 相似文献
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Shaohong Peng Sha Liang Mei Yu Xia Li 《Journal of Material Cycles and Waste Management》2014,16(1):178-185
A new recycling process for the supercritical CO2 (sc-CO2) extraction of polybrominated diphenyl ethers from waste high impact polystyrene (HIPS) was developed in this paper. HIPS was first dissolved in d-limonene. The remaining decabromo diphenyl ether (decaBDE) particles in solution were then removed by centrifugation, and the PBDEs in the centrifugate solution were further extracted by sc-CO2. The influence of temperature and pressure, the volume ratio of sc-CO2 to plastic solution, and the concentration of decaBDE in the solution on the separating efficiency were investigated. The decaBDE particles in 20 % of the HIPS solution can be removed by centrifugation at a speed of 10,000 r/min at 30 °C. The suitable sc-CO2 fluid conditions were 65 °C and 20 MPa, and the optimum volume ratio of the sc-CO2 to the HIPS solution was 2:1. More than 97 % of the PBDEs were successfully removed, and the concentration of PBDE residues in the recycled HIPS was reduced to lower than 0.1 % (dry) by this recycling process. 相似文献
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通过电化学的方法将结晶紫聚合在玻碳电极表面制备聚结晶紫(PCV)膜修饰电极,并研究了对苯二酚和邻苯二酚在PCV膜修饰电极上的电化学行为。PCV膜修饰电极对对苯二酚和邻苯二酚的氧化有良好的电催化作用。在最佳的实验条件下,氧化峰电流在对苯二酚和邻苯二酚的浓度为4.0×10-6~2.8×10-4mol/L之间呈良好线性关系,对苯二酚和邻苯二酚的线性相关系数分别为0.9991和0.9823,检出限分别为6.2×10-7mol/L和9.0×10-7mol/L。PCV膜修饰电极具有良好的灵敏度、重现性和稳定性,可以应用于实际水样中两种物质的同时测定。 相似文献
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通过构建曝气及未曝气潜流人工湿地小试实验系统,以NaCl为示踪剂开展示踪实验,研究曝气对人工湿地水力特性的影响。实验结果表明,两对比系统均存在不同程度的短流及死区现象,短流主要发生在床体表层,而死区则存在于床体底层。其中未曝气人工湿地系统的流场分布不均匀现象较为严重,示踪剂滞留在床体底层难以回收,系统水力效率较低(0.56)。比较而言,由于气流对水体的扰动作用,曝气对人工湿地系统水力效率有明显改善作用,减缓了床体表层水流速度,提高了示踪剂回收率,缩小了死区的范围,曝气人工湿地系统的水力效率为0.75。 相似文献
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紫球藻的载体培养研究 总被引：1，自引：0，他引：1
通过对紫球藻的载体培养进行的较详细研究,获得了适合于紫球藻培养的理想载体;采用载体培养条件的优化和流加营养物质、通气培养以及半连续培养等培养手段,显著提高了紫球藻细胞的质量浓度（ρｍａｘ ＝５．５２ ｇ Ｌ－ １） ． 实验结果表明,利用载体法培养紫球藻不仅能有效地实现高密度培养,易于实现该微藻的连续或半连续培养,而且为细胞的采收带来了很大的方便 相似文献
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Qian Zhuozhen Tang Shuifen Liu Zhiyu Luo Fangfang Wei Shaohong 《Environmental monitoring and assessment》2022,194(5):1-25
Environmental Monitoring and Assessment - An accidental or intentional contamination event can raise health and sociopolitical concerns, erode public trust, and affect the operation of water... 相似文献
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Shaohong Wu Jikun Huang Yanhua Liu Jiangbo Gao Jun Yang Wentao Wang 《中国人口．资源与环境(英文版)》2013,11(2):95-102
Climate change strongly affected the structure and functions of natural ecosystems, e.g. the vegetation productivity decreased in the Northeast permafrost region due to the higher temperature and less precipitation, whereas in the Tibetan Plateau, the vegetation productivity increased, owing to the improved thermal resource. Climate change led to reduced precipitation in North and Northeast China and thus the reduced surface runoff. The public needs for energy were changed because of climate change, e.g. the shorter heating period in winter. Climate change profoundly influenced human health, pathophoresis and major projects by increasing extreme events, including frequency and magnitude, and causing more serious water shortage. Under the background of climate change, although the improved thermal resources can be helpful for extending the crop growth period, more extreme events may resulted in more instability in agricultural productivity. Not only did climate change indirectly affect the secondary and tertiary industries through the impacts on agriculture and natural resources, but also climate change mitigation measures, such as carbon tax, tariff and trading, had extensive and profound influences on the socioeconomic system. Further analysis indicated that the impact of climate change presented significant regional differences. The impact had its pros and cons, while the advantages outweighed the disadvantages. Based on the above analysis on the impacts of climate change, we put forward suggestions on coping with climate change. First, scientifically dealing with climate change will need to seek advantages while avoiding the disadvantages of climate change in order to achieve the orderly adaptation to climate change, which is characterized with “Overall best, long-term benefit.” Second, quantitative adaptation should be given more attention, e.g. proposing operational schemes and predictable goals and using uncertainty analysis on adaptation measures. Third, more active coping strategy should be adopted to enhance China’s future comprehensive competitiveness. The strategies include but are not limited to gradually adjusting the industrial structure, intensifying the research and development (R&D) of emission reduction technology and actively responding to the influence of carbon tax, tariff and trading on socioeconomic development in China. 相似文献
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Projection of hazard changes in climate extremes is critical to assessing the potential impacts of climate change on human and natural systems. Using simulations of providing regional climates for impacts studies, five indicators (rainstorm days, maximum 3-day precipitation, elevation, gradient and distance from river or lake) were selected to project the spatial patterns of flood hazard over Yangtze River Basin for the baseline period (1961– 1990) and future (2011–2100) under SRES B2 scenario. The results ... 相似文献
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