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171.
论文探讨了电气石、不同微生物、以及电气石与枯草芽孢杆菌(Baccillus subtilis,简写B.subtilis)联合对Pb2+的吸附效果。研究表明,溶液pH=5时,电气石吸附效率比B.subtilis高7.9%,当溶液pH值升到55时,B.subtilis和电气石对Pb2+的吸附效率均升高,但B.subtili...  相似文献   
172.
典型气浮净水设备评述   总被引:3,自引:0,他引:3  
文章主要从气浮设备的原理与结构、优缺点、应用情况等方面评述了加压溶气气浮设备、涡凹气浮设备、浅层气浮设备、电气浮设备、充气水力旋流器、多段环流气浮塔和旋流-充气气浮系统等气浮设备,并讨论了气浮设备的研究和应用发展趋势。  相似文献   
173.
概述了物化法处理垃圾渗滤液的研究现状和最新进展,并展望了物化法处理垃圾渗滤液的研究方向。  相似文献   
174.
生产聚氨酯(PU)合成革的废水中含有高浓度有机物,其中N,N-二甲基甲酰胺(DMF)毒性大,难生物降解.文章阐述了合成革的生产工艺,分析该过程中DMF废水形成阶段、处理现状及其处理方法.结合各种方法的优缺点,展望了DMF废水的处理研究方向.  相似文献   
175.
生物完整性指数是水体生态系统健康评价的重要指标,已被广泛应用于湖泊河流等的生态系统健康评价中.但利用水体中分解者微生物群落构建IBI评价标准的报道很少,针对地下水生态系统的研究更是鲜见.本研究针对包钢稀土尾矿库周边地下水生态系统健康开展评价工作,基于地下水环境中微生物群落Illumina高通量测序信息,筛选关键环境因子,甄别敏感或耐受微生物分类属,确定候选生物参数,探索针对地下水的微生物完整性指数(microbiome index of biotic integrity,M-IBI)评价流程与标准构建方法.结果表明,总计12个地下水样点中,4个样点属于健康等级(Ⅰ级),占总样点的33.3%;2个样点属于亚健康等级(Ⅱ级),占总样点的16.7%;5个样点属于一般等级(Ⅲ级),占41.7%;1个样点属于较差等级(Ⅳ级),占8.3%;总体来看,靠近尾矿库的样点健康等级较低,而远离尾矿库参照点受到的干扰较小,健康等级较高,这可能与人类活动干扰影响程度密切相关.参照该地区地下水理化参数基础上的水质情况分析结果,发现应用M-IBI指数可较合理地评估包头稀土尾矿区周边地下水生态系统健康状况.结合生态系统健康内涵,本研究初步提出针对地下水生态系统健康的M-IBI指数评价体系构建流程.  相似文献   
176.
The responses of sulfur (S) uptake assimilation-related genes' expression in roots of two rice cultivars to cadmium (Cd), bensulfuron-methyl (BSM) and their co-contamination (Cd+BSM) were investigated by gene-chip microarray analysis and quantitative real-time PCR (QRT-PCR) technology. Treatments of Cd and Cd+BSM induced expression of sulfate transporter and permease genes, and promoted sulfate uptake in rice roots. Cd+BSM could alleviate Cd toxicity to cv. Fengmeizhan seedlings, probably due to Cd+BSM promoting greater S absorption by seedlings. Cd and Cd+BSM induced expression of sulfate assimilation-related genes, and thus activated the sulfur assimilation pathway. Cd and Cd+BSM induced expression of phytochelatin synthase and metallothionein genes, and induced expression of glutathione S-transferases (GSTs), glutathione synthase (GS) and S- containing antioxidation enzyme genes, which detoxified Cd2+. It is suggested that (to cope with the toxicity of Cd, BSM and their co-contamination) the S uptake and assimilation pathway was activated in rice roots by increased expression of related genes, thus enhancing the supply of organic S for synthesis of Cd or BSM resistance-related substances.  相似文献   
177.
Mo-modified Pd/Al2O3catalysts were prepared by an impregnation method and tested for the catalytic combustion of benzene. The catalysts were characterized by N2 isothermal adsorption, X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), temperatureprogrammed desorption of NH3(NH3-TPD), H2temperature-programmed reduction(H2-TPR), and high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM). The results showed that the addition of Mo effectively improved the activity and stability of the Pd/Al2O3catalyst by increasing the dispersion of Pd active components, changing the partial oxidation state of palladium and increasing the oxygen species concentration on the surface of catalyst. In the case of the Pd-Mo/Al2O3catalyst,benzene conversion of 90% was obtained at temperatures as low as 190°C, which was 45°C lower than that for similar performance with the Pd/Al2O3catalyst. Moreover, the 1.0% Pd-5% Mo/Al2O3catalyst was more active than the 2.0% Pd/Al2O3catalyst. It was concluded that Pd and Mo have a synergistic effect in benzene catalytic combustion.  相似文献   
178.
The photocatalytic degradation of methylene blue(MB) over Fe-doped CaTiO3 under UV-visible light was investigated. The as-prepared samples were characterized using X-ray diffraction(XRD), scanning electron microscope(SEM) equipped with an energy dispersive spectrometer(EDS) system, Fourier transform infrared spectra(FT-IR), and UV-visible diffuse reflectance spectroscopy(DRS). The results show that the doping with Fe significantly promoted the light absorption ability of CaTiO3 in the visible light region. The Fe-doped CaTiO3 exhibited higher photocatalytic activity than CaTiO3 for the degradation of MB.However, the photocatalytic activity of the Fe-doped CaTiO3 was greatly influenced by the calcination temperature during the preparation process. The Fe-doped CaTiO3 prepared at500°C exhibited the best photocatalytic activity, with degradation of almost 100% MB(10 ppm)under UV-visible light for 180 min.  相似文献   
179.
Higher concentrations of Hg can be emitted from coal pyrolysis or gasification than from coal combustion, especially elemental Hg. Highly efficient Hg removal technology from coal-derived fuel gas is thus of great importance. Based on the very excellent Hg removal ability of Pd and the high adsorption abilities of activated carbon(AC) for H2 S and Hg, a series of Pd/AC sorbents was prepared by using pore volume impregnation, and their performance in capturing Hg and H2 S from coal-derived fuel gas was investigated using a laboratory-scale fixed-bed reactor. The effects of loading amount, reaction temperature and reaction atmosphere on Hg removal from coal-derived fuel gas were studied. The sorbents were characterized by N2 adsorption, X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS). The results indicated that the efficiency of Hg removal increased with the increasing of Pd loading amount, but the effective utilization rate of the active component Pd decreased significantly at the same time. High temperature had a negative influence on the Hg removal. The efficiency of Hg removal in the N2-H2S-H2-CO-Hg atmosphere(simulated coal gas) was higher than that in N2-H2S-Hg and N2-Hg atmospheres, which showed that H2 and CO, with their reducing capacity, could benefit promote the removal of Hg. The XPS results suggested that there were two different ways of capturing Hg over sorbents in N2-H2S-Hg and N2-Hg atmospheres.  相似文献   
180.
通过对典型大型浮顶储罐雷击事故分析,总结了这些事故的共性问题。结合浮顶储罐雷击形式及雷电火花放电研究,分析了大型浮顶储罐雷击火灾事故的机理。岚山输油站在等电位连接、一次密封形式结构等方面进行技术改造,经过验证这些措施有效减少了大型浮顶储罐火灾事故的发生。  相似文献   
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