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研究了兼氧型MBR工艺中,当溶解氧控制在0.1~3.0 mg/L时,兼性厌氧菌和厌氧菌所占比例达80%。实验进水COD浓度为60~600 mg/L,COD去除率平均达93%;MLVSS浓度一直保持稳定,平均值为11 090 mg/L,而无机灰分浓度逐渐积累,实验开始时为3 107 mg/L,实验结束时达5 830 mg/L。结果表明,兼氧型MBR工艺可实现污泥自消化,不排放有机性污泥。兼氧型MBR工艺还对膜组件有一定自清洁作用,运行周期可达4个月。实验证明,兼氧型MBR工艺具有处理效率高、不排放有机污泥以及减轻膜污染的特点,是一种创新性的污水处理技术。 相似文献
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Soil samples were collected from three plots under different land utilization patterns including degradation,farming,and restoration.The abundances of methanotrophs were quantified using real-time polymerase chain reaction(PCR)based on the pmoA and 16S rRNA genes,and the community fingerprint was analyzed using denaturing gradient gel electrophoresis(DGGE)aiming at pmoA gene.Significantly lower 16S rRNA and pmoA genes copies were found in the degradation treatment than in farming and restoration.Higher abundances of Type Ⅰ than those of Type Ⅱ methanotrophs were detected in all treatments.The treatment of farming was clearly separated from degradation and restoration according to the DGGE profile by cluster analysis.The lowest diversity indices were observed in the F(farming plot),suggesting that the community structure was strongly affected by farming activities.There were significantly positive correlations between the copy numbers of pmoA also Type Ⅱ-related 16S rRNA genes and soil available K content.Strong negative and positive correlations were found between Type Ⅰ and soil pH,and available P content,respectively.We concluded that the vegetation cover or not,soil characteristics including pH and nutrients of P and K as a result of anthropogenic disturbance may be key factors affecting methanotrophic communities in upland soil. 相似文献
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