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151.
152.
Dong Hu Jie Zeng Jing Chen Wenfang Lin Xinyan Xiao Mingbao Feng Xin Yu 《环境科学学报(英文版)》2023,35(3):148-159
Urban villages are unique residential neighborhoods in urban areas in China. Roof tanks are their main form of water supply, and water quality deterioration might occur in this system because of poor hygienic conditions and maintenance. In this study, water samples were seasonally collected from an urban village to investigate the influence of roof tanks as an additional water storage device on the variation in the microbial community structure and pathogenic gene markers. Water stagnation in th... 相似文献
153.
根据源于节节麦抗禾谷孢囊线虫基因Cre3及已经克隆的NBS-LRR类植物抗病基因的NBS与LRR区保守序列分别设计特异引物,从易变山羊草基因组中PCR扩增得到两个扩增条带,它们的大小分别约为530bp和1200bp.经克隆测序发现,这两个序列分别长为532bp和1175bp,且是连续的.它们有32bp的共同序列,总长为1675bp,包含了一个NBS-LRR区和一个不完整的开放阅读框,没有起始密码子、终止密码子和内含子结构.它编码一个557个氨基酸的蛋白质,分子量(Mr)为63.537×103,含有NBS区保守模体ILDD,ESKILVTTRSK,KGSPLAARTVGG,RRC-FAYCS,EGF,以及LRR区的保守模体aXXLXXLXXL.它与Cre3的核苷酸和氨基酸同源性分别为87.8%和77%,可能是一个抗禾谷孢囊线虫基因.图6参13 相似文献
154.
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156.
对序批式反应器 (SBR)用于牛场污水的处理进行了试验研究 ,主要研究了三个水力停留时间 (HRT)和有机负荷率对污染物去除率、出水水质和污泥特性的影响。试验结果表明 ,对 10 0 0 0mg/LCOD牛场污水 ,使用 1dHRT ,相应有机负荷率为 10gCOD/L·d时 ,混合出水COD、TS、VS、TKN和TN的去除率分别为 45 %、2 1.4%、34 .2 %、5 3.2 %和 2 2 .2 % ,上清液出水的分别为 80 .2 %、6 3.4%、6 6 .2 %、75 %和 38.3% ;两种出水的SCOD和NH3 N去除率相同 ,分别为 5 0 .0 %和 76 .5 %。经SBR处理后 ,污泥的沉降浓缩性能也有了比较明显的改善。 相似文献
157.
序批式生物膜法同步除磷脱氮特性研究 总被引:6,自引:0,他引:6
对淹没序批式生物膜法去除有机物和磷及同步部分脱氮的特性进行了研究。其适合的载体装填密度为30%,水力停留时间为9h,其中厌氧3h,好氧6h,进水COD负荷从0.27kg/(m^3.d)到1.32kg/(m^3.d)均可使除磷率达90%以上,脱氮率达50%-60%。淹没式生物膜法除磷脱氮工艺中的优势菌属为假单胞菌属,其次依顺序为气单胞菌属,芽孢杆菌属,微球菌属,硝化矸菌属,生物膜具有生物量大(MLVSS达5531.7mg/L),脱落污泥含磷量高(达5.67%),沉降性好(SVI为101.7)的特点,污泥产率为0.1996kg干泥/kgCOD。 相似文献
158.
Xu Zhengyong Yang Zhaohui Zeng Guangming Xiao Yong Deng Jiuhua 《Frontiers of Environmental Science & Engineering in China》2007,1(1):43-48
The nitrogen removal mechanism was studied and analyzed when treating the ammonium-rich landfill leachate by a set of sequencing
batch biofilm reactors (SBBRs), which was designed independently. At the liquid temperature of (32 ± 0.4)°C, and after a 58-days
domestication period and a 33-days stabilization period, the efficiency of ammonium removal in the SBBR went up to 95%. Highly
frequent intermittent aeration suppressed the activity of nitratebacteria, and also eliminated the influence on the activity
of anaerobic ammonium oxidation (ANAMMOX) bacteria and nitritebacteria. This influence was caused by the accumulation of nitrous
acid and the undulation of pH. During the aeration stage, the concentration of dissolved oxygen was controlled at 1.2–1.4
mg/L. The nitritebacteria became dominant and nitrite accumulated gradually. During the anoxic stage, along with the concentration
debasement of the dissolved oxygen, ANAMMOX bacteria became dominant; then, the nitrite that was accumulated in the aeration
stage was wiped off with ammonium simultaneously.
Translated from Acta Scientiae Circumstantiae, 2006, 26(1): 55–60 [译自: 环境科学学报] 相似文献
159.
Li Jun Peng Yongzhen Gu Guowei Wei Su 《Frontiers of Environmental Science & Engineering in China》2007,1(2):246-250
An aerobic sequencing batch biofilm reactor (SBBR) packed with Bauer rings was used to treat real domestic wastewater for
simultaneous nitrification and denitrification. The SBBR is advantageous for creating an anoxic condition, and the biofilm
can absorb and store carbon for good nitrification and denitrification. An average concentration of oxygen ranging from 0.8
to 4.0 mg/L was proved very efficient for nitrification and denitrification. Volumetric loads of TN dropped dramatically and
effluent TN concentration increased quickly when the concentration of average dissolved oxygen was more than 4.0 mg/L. The
efficiency of simultaneous nitrification and denitrification (SND) increased with increasing thickness of the biofilm. The
influent concentration hardly affected the TN removal efficiency, but the effluent TN increased with increasing influent concentration.
It is suggested that a subsequence for denitrification be added or influent amount be decreased to meet effluent quality requirements.
At optimum operating parameters, the TN removal efficiency of 74%–82% could be achieved.
Translated from Acta Scientiae Circumstantiae, 2006, 26(5): 728–733 [译自: 环境科学学报] 相似文献
160.
SBBR工艺的现状与发展 总被引:9,自引:0,他引:9
序批式生物膜反应器(SBBR)是目前正在研究、应用的一种污水生物处理新工艺,它是在SBR的基础上发展起来的,既保留了SBR的诸多优点,又有不同于SBR的特点。由于SBBR工艺的脱氮除磷效果好,自动化程度高,运行管理简单,基建费用低,运行费用省,推广到城市污水处理中,必将产生良好的环境效益和社会效益,其应用前景十分广阔。 相似文献