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141.
在注重环境保护的社会下,在全球化追求环境利益最大化的当代社会,环境保护工作已经上升到了一个相当高的高度,我国的环境影响评价制度要与时俱进的发展,才能满足时代的更新换代,环境影响评价的制度化建设涉及到很多方面,从体制,法律,或者是制度的完整度上来看,都还存在不足之处,努力完善这项工作是解决问题的关键. 相似文献
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对闸北区空气自动监测站2009年SO2、NO2、PM10的浓度和气象参数变化特征进行研究,可吸入颗粒物的时间变化特征表明,总体上呈现冬春季高、夏秋季低;PM10与降水量、相对湿度、温度呈现一定的负相关性,但与风速的相关性随季节不同而不同,与气压略呈正相关性。对典型日和灰霾日PM10、SO2、NO2以及相应气象因子的特征进行了分析比较。 相似文献
146.
Jingjing Shao Yan Cheng Chunping Yang Guangming Zeng Wencan Liu Panpan Jiao Huijun He 《环境科学学报(英文版)》2016,28(9):120-129
Naphthalene-2-ol is a typical biologically recalcitrant pollutant in dye wastewater.Solvent extraction of naphthalene-2-ol from aqueous solutions using mixed solvents was investigated.Various extractants and diluents were evaluated,and the effects of volume ratio of extractant to diluent,initial p H,initial concentration of naphthalene-2-ol in aqueous solution,extraction time,temperature,volume ratio of organic phase to aqueous phase(O/A),stirring rate and extraction stages,on extraction efficiency were examined separately.Regeneration and reuse of the spent extractant were also investigated.Results showed that tributyl phosphate(TBP) achieved 98% extraction efficiency for naphthalene-2-ol in a single stage extraction,the highest among the 12 extractants evaluated.Extraction efficiency was optimized when cyclohexane and n-octane were used as diluents.The solvent combination of 20% TBP,20% n-octanol and 60% cyclohexane(V/V) obtained the maximum extraction efficiency for naphthalene-2-ol,99.3%,within 20 min using three cross-current extraction stages under the following extraction conditions:O/A ratio of 1:1,initial p H of 3,25°C and stirring rate of 150 r/min.Recovery of mixed solvents was achieved by using 15%(W/W) Na OH solution at an O:A ratio of 1:1 and a contact time of 15 min.The mixed solvents achieved an extraction capacity for naphthalene-2-ol stably higher than90% during five cycles after regeneration. 相似文献
147.
A novel silica catalyst was synthesized by evaporation-induced self-assembly (EISA) method and tested for the catalytic selective hydrolysis of cellulose to glucose. This silica catalyst exhibited a higher catalytic activity than other oxides prepared by the same method, such as ZrO2, TiO2, and Al2O3. Using silica as a catalyst, cellulose was selectively hydrolyzed into glucose with a glucose yield as high as 50% under hydrothermal conditions without hydrogen gas. The silica catalyst was characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results of temperature-programmed desorption of ammonia (NH3-TPD) and textural properties indicated that the synergistic effect between strong acidity and a suitable pore diameter of the silica catalyst may be responsible for its high activity. In addition, the catalyst was recyclable and showed excellent stability during the recycle catalytic runs. 相似文献
148.
Pinjing He Min Li Suyun Xu Liming Shao 《Frontiers of Environmental Science & Engineering in China》2009,3(4):404-411
This paper describes the feasibility of fresh leachate treatment by an upflow blanket filter (UBF). Through dilution and partial
effluent recycling, the organic loading rates increased from 0.51 to 14.56 kg COD/(m3·d), meanwhile the corresponding hydraulic retention time decreased from 9.0 to 3.6 d. The reactor was able to achieve steady-state
within 80 d. Based on the distribution of COD fluxes in the process, it was concluded that anabolism was the main pathway
of COD removal in the initial phase (1–33 d), accounting for 57%–85% of total COD removed. As the anaerobic consortium of
bacteria reached steady-state (after 70–86 d), the majority of COD removed was transformed into methane, because the specific
methane yield was close to the theoretical value (0.36 L CH4/(g CODdeg)). 相似文献
149.
滦河锡林郭勒盟段水质状况评价 总被引:1,自引:0,他引:1
利用水质指数法对滦河锡林郭勒盟段水质状况进行了分析评价,结果显示:(1)滦河锡林郭勒段2005-2007年主要污染因子为:高锰酸盐指数、化学需氧量、铁、生物需氧量、锰、总磷等;(2)2005-2007年间,上都河监测断面水质状况整体呈变好趋势,但地方经济增长带来的化学需氧量异常升高不容忽视,大河口断面不同水期水质状况变化不同;(3)2005-2007年,滦河锡林郭勒段化学需氧量与溶解氧超标污染加重明显、高锰酸盐指数超标污染逐渐减轻;三年内,上游水质均优于下游水质,两个监测断面水质均为丰水期水质〈平水期水质〈枯水期水质。 相似文献
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