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271.
272.
Liu Rui Zhou Qixing Zhang Lanying Guo Hao 《Frontiers of Environmental Science & Engineering in China》2007,1(1):114-119
To make a comprehensive assessment on monosodium glutamate (MSG) wastewater pollution, a pollution exposure experiment was
carried out on the seed germination and root elongation of wheat, Chinese cabbage and tomato by using the wastewater discharged
from different processing phases of MSG production. The results showed that there were significantly positive linear relationships
between the inhibitory rates of wheat seed germination and root elongation and the CODcr of the mother liquor scraps. The toxicity of MSG wastewater to the test crops was in the order of tomato > Chinese cabbage
> wheat, indicating that tomato was the most sensitive to the wastewater, and could be considered as an ideal toxic bioindicator.
The half-effect concentrations (IC50) based on the seed germination and root elongation of the test crops exposed to the wastewater discharged from various processing
phases of MSG production was 22.0–32 432 and 17.3–3320 mg/L, respectively.
Translated from Chinese Journal of Applied Ecology, 2006, 17(7): 1286–1290 [译自: 应用生态学报] 相似文献
273.
Nitrobenzene is an important raw material and product,which presents a heavy threat to the ecosystem.The potential impacts of nitrobenzene on sediment oxygen demand (SOD) were studied in lake sediment ... 相似文献
274.
Harish Venkatakrishnan Youming Tan Maszenan bin Abdul Maji Santosh Pathak Antonius Yudi Sendjaj Dongzhe Li Jerry Jian Lin Liu Yan Zhou Wun Jern Ng 《环境科学学报(英文版)》2014,26(4):875-884
A high strength chemical industry wastewater was assessed for its impact on anaerobic microbial com- munity dynamics and consequently mesophilic methane generation. Cumulative methane production was 251 mL/g total chemical oxygen demand removed at standard temperature and pressure at the end of 30 days experimental period with a highest recorded methane percentage of 80.6% of total biogas volume. Volatile fatty acids (VFAs) analysis revealed that acetic acid was the major intermediate VFAs produced with propionic acid accumulating over the experimental period. Quantitative analysis of microbial communities in the test and control groups with quantitative real time polymerase chain reaction highlighted that in the test group, Eubacteria (96.3%) was dominant in comparison with methanogens (3.7%). The latter were dominated by Methanomicrobiales and Methanobacteriales while in test groups increased over the experimental period, reaching a maximum on day 30. Denaturing gradient gel electrophoresis profile was performed, targeting the 16S rRNA gene of Eubacteria and Archaea, with the DNA samples extracted at 3 different time points from the test groups. A phylogenetic tree was constructed for the sequences using the neighborhood joining method. The analysis revealed that the presence of organisms resembling Syntrophomonadaceae could have contributed to increased production of acetic and propionic acid intermediates while decrease of organisms resembling Pelotomaculum sp. could have most likely contributed to accumulation of propionic acid. This study suggested that the degradation of organic components within the high strength industrial wastewater is closely linked with the activity of certain niche microbial communities within eubacteria and methanogens. 相似文献
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277.
重庆市主城区及近郊居民环境意识状况分析 总被引:8,自引:0,他引:8
采用非概率抽样方法,对重庆市主城区及近郊区居民共542户进行入户调查,分析了居民环境意识状况,发现环境意识水平与文化,经济水平以及信息媒体有密切关系,并提出了具体建议。 相似文献
278.
以石家庄市显像管玻壳厂排放的铅尘为研究对象,通过在该玻壳厂周围土壤布点采样,较系统地研究了铅尘在大气和周围土壤中的迁移和转化规律,研究表明,用高斯模式能成功地预测铅尘在大气中的迁移扩散规律,玻壳厂周围土壤表层铅含量较大值出现在当地年主导风向(SSE,N)下风向,铅在土壤中的分布主要集中在0-20cm的耕作层,在20-40cm深度范围内,铅含量呈下降趋势,最大降幅达50%。 相似文献
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280.
聚丙烯酰胺对聚合物驱含油污水中油珠沉降分离的影响 总被引:37,自引:1,他引:37
研究发现阴离子聚丙烯酰胺(HPAM)对聚合物驱含油污水处理有正反2方面影响.聚合物能增加污水粘度,降低油珠上浮速度,而且聚合物能增加油水界面水膜强度,延缓油珠聚并时间,这是聚合物对油珠沉降分离的不利影响;同时,聚丙烯酰胺具有絮凝性,能将水中油珠连接到一起,有利于油珠聚并.当聚丙烯酰胺相对分子质量为2.72×106,浓度小于800mg/L时,絮凝作用大于粘度作用,有利于油珠的沉降分离.初始油珠粒径小是聚合物驱含油污水难处理的主要原因.横向流除油器可以加速油珠聚并,缩短沉降时间,适合处理聚合物驱含油污水. 相似文献