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991.
从燃煤电厂排出的烟气分离技术,分为即燃烧前处理、富氧燃烧以及燃烧后处理三类,阐述燃烧后的处理方法.这种方法有五大技术发展方向,包括吸收、吸附、膜分离、霜冻分离和生物捕捉.对这五个方向的技术做一些阐述,并列举这几个方向下正在开展的研究实例,对二氧化碳捕集技术做一个较全面的介绍. 相似文献
992.
To sufficiently utilize chemically active species and enhance the degradation rate and removal efficiency of toxic and biorefractory organic pollutant para-chlorophenol (para-CP), the introductions of iron metal ions (Fe2+/Fe3+) into either pulsed discharge plasma (PDP) process or the PDP process with TiO2 photo-catalyst were tentatively performed. The experimental results showed that under the same experimental condition, the degradation rate and removal efficiency of para-CP were greatly enhanced by the introduction of iron ions (Fe2+/Fe3+) into the PDP process. Moreover, when iron ions and TiO2 were added together in the PDP process, the degradation rate and removal energy of para-CP further improved. The possible mechanism was discussed that the obvious promoting effects were attributed to ferrous ions via plasma induced Fenton-like reactions by UV light irradiation excited and hydrogen peroxide formed in pulsed electrical discharge, resulting in a larger amount of hydroxyl radicals produced from the residual hydrogen peroxide. In addition, the regeneration of ferric ions to ferrous ions facilitates the progress of plasma induced Fenton-like reactions by photo-catalytic reduction of UV light, photo-catalytic reduction on TiO2 surface and electron transfer of quinone intermediates, i.e. 1,4-hydroquinone and 1,4-benzoquinone. 相似文献
993.
Lorenz M Nagel HD Granke O Kraft P 《Environmental pollution (Barking, Essex : 1987)》2008,155(3):426-435
Intensive forest monitoring by means of harmonised methods has been conducted in Europe for more than a decade. Risks of atmospheric nitrogen and sulphur deposition are assessed by means of calculations of critical loads and their exceedances. In the present study throughfall and bulk deposition of nitrate (N-NO(3)), ammonium (N-NH(4)) and sulphate (S-SO(4)) show marked spatial patterns and temporal trends. In the period of observation (1999-2004), sulphate deposition on intensive monitoring plots decreased by about one quarter. This is in line with the reduction of S deposition by 70% since 1981 in Europe as a result of successful air pollution control politics under the Convention on Long-range Transboundary Air Pollution (CLRTAP). However, sulphate and especially nitrate and ammonium deposition were found to still exceed critical loads at many forest sites, indicating a continued need for further implementation of air pollution abatement strategies. 相似文献
994.
Stomatal characteristics and infection biology of Pyrenopeziza betulicola in Betula pendula trees grown under elevated CO2 and O3 总被引:2,自引:0,他引:2
Riikonen J Syrjälä L Tulva I Mänd P Oksanen E Poteri M Vapaavuori E 《Environmental pollution (Barking, Essex : 1987)》2008,156(2):536-543
Two silver birch clones were exposed to ambient and elevated concentrations of CO2 and O3, and their combination for 3 years, using open-top chambers. We evaluated the effects of elevated CO2 and O3 on stomatal conductance (gs), density (SD) and index (SI), length of the guard cells, and epidermal cell size and number, with respect to crown position and leaf type. The relationship between the infection biology of the fungus (Pyrenopeziza betulicola) causing leaf spot disease and stomatal characteristics was also studied. Leaf type was an important determinant of O3 response in silver birch, while crown position and clone played only a minor role. Elevated CO2 reduced the gs, but had otherwise no significant effect on the parameters studied. No significant interactions between elevated CO2 and O3 were found. The infection biology of P. betulicola was not correlated with SD or gs, but it did occasionally correlate positively with the length of the guard cells. 相似文献
995.
Hauck M 《Environmental pollution (Barking, Essex : 1987)》2008,152(3):731-735
The effective quantum yield of photochemical energy conversion in photosystem II (Phi2) was shown to be reduced in the terricolous lichens Cetraria aculeata and Cetraria islandica by short-term exposure to aqueous SO2 at pH values occurring in the precipitation of areas with high SO2 pollution. Significant reduction of Phi2 was found at pH相似文献
996.
997.
用混合二元酸制备混合酸二甲酯 总被引:1,自引:0,他引:1
以工业副产物混合二元酸(DBA)和甲醇为原料,用自制PW12/SiO2作催化剂制备混合酸二甲酯(DME),确定了最佳制备条件:甲醇与DBA摩尔比为3.5,PW12/SiO2加入量(PW12/SiO2中PW12占DBA的质量分数)为2%,反应时间为4.5h,100gDBA中甲苯加入量为50mL。在此最佳条件下,DME收率为84.7%,所得DME为无色澄清液体,其中丁二酸二甲酯的质量分数为11.03%,戊二酸二甲酯的质量分数为13.88%,己二酸二甲酯的质量分数为73.79%。PW12/SiO2具有较好的稳定性和一定的重复使用性,PW12/SiO2重复使用5次时的DME收率仍大于70%。 相似文献
998.
总量控制是国家节能减排的主要手段,二氧化硫排放量控制是大气污染物削减的主要控制指标。在污染源普查数据统计分析的基础上,对伊宁市废气中二氧化硫排放按污染源和区域进行分担率研究,掌握并了解产生排放二氧化硫按污染源、区域、行业分布情况,确定伊宁市二氧化硫减排的重点行业和区域,为政府调整产业结构及企业合理布局提供决策依据。 相似文献
999.
The effects of elevated concentrations of atmospheric tropospheric ozone (O3) on DNA damage in five trembling aspen (Populus tremuloides Michx.) clones growing in a free-air enrichment experiment in the presence and absence of elevated concentrations of carbon dioxide (CO2) were examined. Growing season mean hourly O3 concentrations were 36.3 and 47.3 ppb for ambient and elevated O3 plots, respectively. The 4th highest daily maximum 8-h ambient and elevated O3 concentrations were 79 and 89 ppb, respectively. Elevated CO2 averaged 524 ppm (+150 ppm) over the growing season. Exposure to O3 and CO2 in combination with O3 increased DNA damage levels above background as measured by the comet assay. Ozone-tolerant clones 271 and 8L showed the highest levels of DNA damage under elevated O3 compared with ambient air; whereas less tolerant clone 216 and sensitive clones 42E and 259 had comparably lower levels of DNA damage with no significant differences between elevated O3 and ambient air. Clone 8L was demonstrated to have the highest level of excision DNA repair. In addition, clone 271 had the highest level of oxidative damage as measured by lipid peroxidation. The results suggest that variation in cellular responses to DNA damage between aspen clones may contribute to O3 tolerance or sensitivity. 相似文献
1000.
基于湿法再生吸附技术,利用强碱性季铵盐树脂材料制备了异相吸附剂薄膜,应用于大气中极低CO2的直接分离,以对抗全球变暖。通过滴定法分析吸附剂材料的电荷密度和吸附容量,利用SEM分析不同工况下制备出来的膜材料的表观结构,并对膜材料进行CO2吸附性能的测试。结果发现,热处理能够明显提高膜材料的吸附性能,还研究吸附剂制备对吸附速率,吸附量和机械强度等性能的影响,发现粒径小于43μm的树脂粉末,按60%质量分数制成的500μm厚膜材料具有较优的综合性能。 相似文献