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931.
本文应用粉煤灰渗滤系统处理北方寒冷地区城市污水,结果细菌数量去除率在89.6%—99.9%之间,粪大肠菌群数量去除率在90%—99.9%之间,此方法成本低、效果好,适合北方中小城镇污水处理。  相似文献   
932.
本文研究了厌氧方法驯化的活性污泥中筛选出的一株活力苯酚厌氧降解菌降解苯酚的最佳条件。结果为:在基础选择培养基中以1.0g(NH4)2SO4作为氮源并且在1 L培养基中加入1 mL微量元素储备液,调节培养基pH值为6.9-7.2,有利于C. albicans PDY-07降解苯酚。  相似文献   
933.
不同微生物菌剂对畜禽粪便堆肥效果的温度指标研究   总被引:1,自引:0,他引:1  
温度是堆料中微生物生命活动的重要标志,它直接影响堆肥反应速率,是堆肥能否顺利进行的主要因素。通过在畜禽粪便(鸡粪、猪粪、牛粪)中加入辅料和不同微生物菌剂,进行好氧堆肥并测定堆料温度,根据温度结果明确不同微生物菌剂对不同粪便的堆肥效果。  相似文献   
934.
五氯苯酚(PCP)是一类危险性较大的环境污染物。PCP比较稳定,容易在动植物体内富集,导致动物肺、肝、肾脏以及神经系统的损伤。根据国内外最新的研究成果,对PCP的化学和生物降解等方法的研究进展进行综述,并对今后PCP的降解趋势进行了展望。  相似文献   
935.
Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory conditions. The degradation half-lives of chlorpyrifos at levels of 4, 8, and 12 mg/kg in soil were calculated to be 14.3, 16.7, and 18.0 d, respectively. The Biolog study showed that average well color development (AWCD) in soils was significantly (P < 0.05) inhibited by chlorpyrifos within the first two weeks and thereafter recovered to the similar level as the control. A similar variation in the diversity indices (Simpson index 1/D and McIntosh index U) in chlorpyrifos-treated soils was observed, no significant difference in the Shannon-Wiener index H' was found in these soils. With increasing chlorpyrifos concentration, the half-lives of chlorpyrifos were significantly (P ≤ 0.05) extended and its inhibitory effects on soil microorganisms were aggravated. It is concluded that chlorpyrifos residues in soil had a temporary or short-term inhibitory effect on soil microbial functional diversity.  相似文献   
936.
Aerobic granular sludge was cultivated in sequencing batch airlift reactors(SBAR) at 25,30,and 35°C,respectively.The effect of temperature on the granules characteristics was analyzed and the microbial community structures of the granules were probed using scanning electron microscope(SEM) and polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE).The results showed that 30°C is optimum for matured granule cultivation,where the granules had a more compact structure,better settling abili...  相似文献   
937.
ITO/CdS/ZnO interface composite films were successfully prepared by subsequent electrodeposition of CdS and ZnO onto indium tin oxide (ITO) glass substrates. The obtained ITO/CdS/ZnO composite films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy. The photocatalytic activity of ITO/CdS/ZnO composite films were investigated using methyl orange (MO) as a model organic compound under UV light irradiation. The influence of operating parameters on MO degradation including initial concentration of MO, pH value of solution, and inorganic anion species over the composite films were examined. A blue shift of absorption threshold was observed for the ITO/CdS/ZnO film in comparison with ITO/ZnO film. ITO/CdS/ZnO composite films prepared under specific conditions showed a higher photocatalytic activity than that of ITO/ZnO films. It was also found that the photocatalytic degradation of MO on the composite filing followed pseudo-first order kinetics.  相似文献   
938.
水解(酸化)工艺预处理难降解有机废水应用技术分析   总被引:1,自引:0,他引:1  
本文对水解(酸化)工艺进行了原理分析,论述了该工艺的优缺点,以及对后续工艺的影响.分析论述了该工艺对几种典型的难降解有机废水的降解机理.认为水解(酸化)作为难降解有机废水的预处理工艺具有很高的推广应用价值.  相似文献   
939.
<正>"生物多样性"很大程度上取决于外来物种在本土环境中的适应和发展.通常来说,当生存环境发生改变时,寄生生物能为其宿主调节生存竞争压力.已有大量证据表明寄生虫和宿主的确具有本土适应性,但是我们对地球上最为丰富的微生物体——细菌和他们的寄生噬菌体却知之甚少.实际上,微生物多样性最终决定了生态系统的功能和环境的变化.最近一系列的科学研究引发了科学界对微生物多样性的另一话题:那就是生物因素和非生物因素对促进生物多样性的相对重要性.  相似文献   
940.
The current modified electro-Fenton system was designed to develop a more convenient and e cient undivided system for practical wastewater treatment. The system adopted a cathode portion that employed magnetic stirring instead of common oxygen gas di usion or gas sparging to supply oxygen gas for the electrolyte solution. Key factors influencing the cathode fabrication and activity were investigated. The degradation of acid fuchsine with a self-made graphite-polytetrafluorethylene cathode was studied using a spectrophotometer. It was found that the cathode generated hydrogen peroxide with high current e ciency and the hydrogen peroxide yield of the cathode did not decay after 10 times reuse. With the Pt anode at a ferrous ion concentration of 0.5 mmol/L, a pH of 3, and using magnetic stirring, dye decolorization could be rapidly accomplished but the destruction of benzene rings and intermediates was fairly di cult. With a Fe anode, dye degradation was more complete.  相似文献   
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