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991.
The Cu2+-loaded montmorillonite clays (MMT-Cu) may be a good material for the adsorbed and eliminated pathogenic bacteria from aqueous solution. 相似文献
992.
Effect of C/N ratio, aeration rate and moisture content on ammonia and greenhouse gas emission during the composting 总被引:3,自引:0,他引:3
Gaseous emission (N2O, CH4 and NH3) from composting can be an important source of anthropogenic greenhouse gas and air pollution. A laboratory scale orthogonal experiment was conducted to estimate the effects of C/N ratio, aeration rate and initial moisture content on gaseous emission during the composting of pig faeces from Chinese Ganqinfen system. The results showed that about 23.9% to 45.6% of total organic carbon (TOC) was lost in the form of CO2 and 0.8% to 7.5% of TOC emitted as CH4. Most of the nitrogen was lost in the form of NH3, which account for 9.6% to 32.4% of initial nitrogen. N2O was also an important way of nitrogen losses and 1.5% to 7.3% of initial total nitrogen was lost as it. Statistic analysis showed that the aeration rate is the most important factor which could affect the NH3 (p = 0.0189), CH4 (p = 0.0113) and N2O (p = 0.0493) emissions significantly. Higher aeration rates reduce the CH4 emission but increase the NH3 and N2O losses. C/N ratio could affect the NH3 (p = 0.0442) and CH4 (p = 0.0246) emissions significantly, but not the N2O. Lower C/N ratio caused higher NH3 and CH4 emissions. The initial moisture content can not influence the gaseous emission significantly. Most treatments were matured after 37 days, except a trial with high moisture content and a low C/N ratio. 相似文献
993.
Preliminary report on methane emissions from the Three Gorges Reservoir in the summer drainage period 总被引:3,自引:0,他引:3
Fei Lu Le Yang Xiaoke Wang Xiaonan Duan Yujing Mu Wenzhi Song Feixiang Zheng Junfeng Niu Lei Tong Hua Zheng Yongjuan Zhou Jiangxiao Qiu Zhiyun Ouyang 《环境科学学报(英文版)》2011,23(12):2029-2033
Considerable variations may exist in CH4 emissions from the Three Gorges Reservoir. 相似文献
994.
Polyaspartic acid (PASP) has been extensively studied in recent years as a green scale inhibitor. PASP was synthesized by thermal polycondensation of maleic anhydride and ammonium carbonate in this study. The optimal polycondensation reaction conditions were the raw material (maleic anhydride and ammonium carbonate) molar ratio of 1.0:1.2, the polymerization temperature of 180°C and reaction time of 2.0 hr. The results showed that PASP exhibits very good scale inhibiting performance. The inhibition rate was 95% for calcium carbonate and 90% for calcium sulfate by the application of 5 mg/L PASP. 相似文献
995.
Laboratory scale experiments were conducted to study the characteristics of N and P removal under different influent organic carbon concentration in a sequencing batch reactor (SBR) with simple anaerobic/aerobic operating mode. Experimental results indicated that, under the operating condition of influent N concentration of 89 mg/L and P concentration of 15 mg/L, when the influent C/N ratio increased from 1.5 to 6.9 (influent C/P ratio from 9 to 41), total N and P removal efficiency improved from 50% and 46% to 78% and 96% respectively. Track studies of N, P and other operating parameters demonstrated that N removal of the SBR was realized through simultaneous nitrification and denitrification (SND) in the aeration phase and anoxic denitrificaiton in the filling phase, P removal was accomplished through conventional anaerobic P release and aerobic P taken-up process. Keeping dissolved oxygen (DO) concentration during the first two aeration hours as low as 0.1-0.6 mg/L is essential for the simultaneous occurrences of nitrification, denitrification and P-taken up. 相似文献
996.
采用静态实验方法,研究了不同浓度的间甲酚(m-cresol)对斑马鱼胚胎的急性毒性.结果表明,当m-cresol浓度超过一定数值时,伴随着时间的延长可使暴露胚胎的畸形数增加,暴露胚胎孵化出的仔鱼也出现畸形现象,mcresol的毒性呈现出剂量-效应关系.当m-cresol质量浓度不小于13 mg/L时,暴露12 h的胚胎开始出现畸形;质量浓度为25 mg/L时,暴露24 h的胚胎全部畸形.m-cresol对胚胎24 h眼点发育及20 s主动活动、48 h黑色素和72 h各类畸形的EC50分别为33.609,8.882和5.652 mg/L.可见,一定浓度的m-cresol可对斑马鱼胚胎及其孵化仔鱼产生毒性作用. 相似文献
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针对目前廊坊市环保产业发展现状及存在的问题,以及今后一段时间内环保产品市场的需求进行了分析,并提出了一些建议。 相似文献