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411.
In recent years, there have been a number of reports on the phenomenon in which ferric iron(Fe(Ⅲ)) is reduced to ferrous iron [Fe(Ⅱ)] in anaerobic environments, accompanied by simultaneous oxidation of ammonia to NO2-, NO3-, or N2.However, studies on the relevant reaction characteristics and mechanisms are rare. Recently, in research on the effect of Fe(Ⅲ) on the activity of Anammox sludge, excess ammonia oxidization has also been found.Hence, in the present study, Fe(Ⅲ) was used to serve as the electron acceptor instead of NO2-,and the feasibility and characteristics of Anammox coupled to Fe(Ⅲ) reduction(termed Feammox) were investigated. After 160 days of cultivation, the conversion rate of ammonia in the reactor was above 80%, accompanied by the production of a large amount of NO3-and a small amount of NO2-. The total nitrogen removal rate was up to 71.8%. Furthermore,quantities of Fe(Ⅱ) were detected in the sludge fluorescence in situ hybridization(FISH) and denaturated gradient gel electrophoresis(DGGE) analyses further revealed that in the sludge, some Anammox bacteria were retained, and some microbes were enriched during the acclimatization process. We thus deduced that in Anammox sludge, Fe(Ⅲ) reduction takes place together with ammonia oxidation to NO2-and NO3-along with the Anammox process. 相似文献
412.
试论复垦的概念及其与生态重建的关系 总被引:1,自引:0,他引:1
基于国内外大量的文献资料,在剖析国外对“土地复垦”的定义、目标的理解和介绍有关国外复垦法规、复垦研究内容和历史的基础上,从复垦和生态重建的基本概念入手,深入探讨了二者内涵与关系,认为:“复垦”的研究十分重视生态原则,也一直将生态重建作为其研究的焦点。因此,“复垦”一词的实质是既恢复土地资源,又重建生态平衡,即“复垦”包括土地复垦和生态重建两方面。 相似文献
413.
本文主要列举了美国Dasibi1000环境空气自动监测系统中的主要监测仪器氮氧化物、二氧化硫、可吸入颗粒物等分析仪在日常运行中容易出现的一些的常见故障。由于此套仪器设备具有自检功能。可通过仪器面板提示的故障信息找到故障所在。并对其形成原因进行了系统分析和总结。同时提出了一些排除故障的方法和步骤以及避免出现这些故障所需的日常维护。 相似文献
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本文针对内蒙稀土产业,近年发展迅速,但环境污染严重,小冶炼四处泛滥,群众由环境问题不断上访;稀土产业初级产品产量过大,效益明显降低的状况,根据环境经济学理论,提出合理的管理与经济政策。 相似文献
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418.
Qiong Wang Xiao-Hui Bi Jian-Hui Wu Yu-Fen Zhang Yin-Chang Feng 《Environmental monitoring and assessment》2013,185(2):1473-1482
The ambient PM10 and background soil samples were collected and analyzed with ICP-AES in eight cities around China to investigate the levels of ten heavy metals (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pb). The mean concentrations of ten heavy metals in PM10 of the eight cities of China followed the order of Zn?>?Pb?>?Mn?>?Cu?>?Ni?>?Cr?>?Co?>?V. The metals in the ambient PM10 and soil were compared in each city to evaluate the heavy metal mass fraction from anthropogenic sources in ambient air. The CD values in these cities were all above 0.2, indicating that the ingredients spectrums of PM10 and soil vary markedly. Most heavy metals were enriched in PM10, except Fe and Ti. The results showed that almost all the cities suffer important heavy metal pollution from anthropogenic sources. The eight cities were also grouped according to their similarity in heavy metals of ambient PM10 by cluster analysis to investigate the relationship between the heavy metals and the pollution sources of each city. The conclusion was that the eight cities were divided into three clusters which had similar industrial type and economy scale: the first cluster consisted of Shenzhen, Wuxi, and Guiyang; followed by Jinan and Zhengzhou as the second grouping; and the third group had Taiyuan, Urumqi, and Luoyang. 相似文献
419.
毕彩霞 《安全.健康和环境》2008,8(4):46-47
介绍了利用网络平台进行安全培训的特点,分析建立网络平台必须完善的培训条件,确定了安全培训的内容和目标与任务. 相似文献
420.
通过室内循环冻融循环试验和三轴不固结不排水(UU)压缩试验研究了循环冻融作用与细砾组含量(P_(2-5))对黏质粗粒土抗剪性能的影响。结果表明,冻融循环作用对黏质粗颗粒土的应力—应变曲线性状具有一定的影响,可使其由未冻融的应变软化向应变硬化转变的趋势,但随着细砾组P_(2-5)含量的增加,冻融作用对其影响逐渐减弱。随着冻融循环次数的增加,土样剪切强度呈现逐渐衰减,且在5~9次冻融循环次数后基本保持不变,多次循环冻融作用后剪切强度最大衰减幅度可达40%。弹性模量随冻融循环次数的增加上下波动较大但整体呈现下降趋势。在抗剪强度指标方面,冻融作用对黏聚力影响比较显著,随着冻融循环次数的增加,黏聚力逐渐减小,最大衰减幅度可达65%,而内摩擦角上下波动较大无明显趋势。此外,随着细砾组P_(2-5)含量的增加,剪切强度、弹性模量及抗剪强度指标均呈现不同程度的减小,这与粗粒土内部粗颗粒和细颗粒占比及其强度发挥机制有关。 相似文献