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801.
Application of Ruditapes Philippinarum conglutination mud (RPM) for decolorizing synthetic dye solutions was studied. RPM showed good activity for decolorization of Methylene Blue, Crystal Violet, Malachite Green, and Ink Blue. The amount of the RPM had great effect on the decoloration rate of the dye solutions. However, the decoloration rate did not continue to increase when the amount of mud exceeded the optimum dose. The temperature of the dye solution had a remarkable effect on the decolorization rate of Ink Blue solution, but had little effect on the other three dye solutions. The initial pH of the dye solutions evidently affected the decolorization rate of Malachite Green solution, but had less effect on the other three. The decolorization rate of the dye solutions increased significantly with treatment time within 8 hr, but tended to be steady after 8 hr for Methylene Blue, Crystal Violet and Malachite Green solutions, and after 12 hr for Ink Blue solution. The decolorization efficiencies for the four dye solutions under the optimum conditions were all above 90%. Seventeen strains screened from RPM showed flocculation ability for kaolin clay suspension. Out of them, the flocculation rate of strain ZHT3-9 and strain ZHT4-13 were up to 88.14% and 86.01%, respectively. ZHT3-9 was studied, and its decolorization rate for Methylene Blue, Crystal Violet, and Malachite Green reached 90.02%, 89.21%, and 80.29%, respectively. By morphological, physiological and biochemical characteristics analysis and 16S rRNA sequencing, the strain ZHT3-9 was identified as Arthrobacter sp. 相似文献
802.
Laboratory scale experiments were conducted to study the characteristics of N and P removal under different influent organic carbon concentration in a sequencing batch reactor (SBR) with simple anaerobic/aerobic operating mode. Experimental results indicated that, under the operating condition of influent N concentration of 89 mg/L and P concentration of 15 mg/L, when the influent C/N ratio increased from 1.5 to 6.9 (influent C/P ratio from 9 to 41), total N and P removal efficiency improved from 50% and 46% to 78% and 96% respectively. Track studies of N, P and other operating parameters demonstrated that N removal of the SBR was realized through simultaneous nitrification and denitrification (SND) in the aeration phase and anoxic denitrificaiton in the filling phase, P removal was accomplished through conventional anaerobic P release and aerobic P taken-up process. Keeping dissolved oxygen (DO) concentration during the first two aeration hours as low as 0.1-0.6 mg/L is essential for the simultaneous occurrences of nitrification, denitrification and P-taken up. 相似文献
803.
A new type of sponge iron sphere (NSIS) with 1-5 mm diameter, made of concentrated iron powder and possessed high activity and intension, was prepared by mini-pellet sintering integrated with H2 direct reduction. Static state experiment has been carried on to investigate the Cd2+ removal efficiency from wastewater by the NSIS and to explore the Cd2+ removal reaction kinetics. It was suggested that initial pH value and Cd2+ original concentration had significant influence on Cd2+ removal percentage. Cd2+ removal percentage decreased significantly with the increasing of Cd2+original concentration whether the original pH value be adjusted to 3.0 or without adjustment. The results showed that the Cd2+ removal process followed the first order reaction because the reaction order was from 0.803 to 0.996. The apparent reaction rate constant between Cd2+ and NSIS was from 0.0025 to 0.1000 (mg·L?1)1-n·min?1. Compared with SIS reduced by charcoal reduction, NSIS deoxided by hydrogen possessed higher activity, and could remove the same quantity of Cd2+ within a shorter period of time. 相似文献
804.
By using optical microscope, the microstructures of 5083/6082 friction stir welding (FSW) weld and parent materials were analyzed. Meanwhile, at ambient temperature and in 0.2 mol/L NaHS03 and 0.6 mol/L NaCl solutionby gravimetric test, potentiodynamic polarization curve test, electrochemical impedance spectra (EIS) and scanning electron microscope (SEM) observation, the electrochemical behavior of 5083/6082 friction stir welding weld and parent materials were comparatively investigated by gravimetric test, potentiodynamic polarization curve test, electrochemical impedance spectra (EIS) and scanning electron microscope (SEM) observation. The results indicated that at given processing parameters, the anti-corrosion property of the dissimilar weld was superior to those of the 5083 and 6082 parent materials. 相似文献
805.
806.
以近年Landsat TM 遥感图像为基础数据源,利用遥感与GIS技术对沈阳市生态环境状况进行了监测.结果表明,2009年间沈阳市生态环境质量处于一般水平,与2008年相比,生态环境质量指数上升,生态环境状况呈现变好的趋势. 相似文献
807.
在分析沈阳市NOx排放现状及发展趋势基础上,针对NOx总量控制工作中存在基础薄弱、污染物增量大、治理技术上存在不确定因素等实际问题,总结了"增量控制,存量削减"的总体工作思路,并提出了实施电力企业脱硝工程改造的对策和建议. 相似文献
808.
809.
810.
应用氢化物原子荧光法,测定鲤鱼肝脏中痕量Hg和As,该法具有原子吸收和原子发射光谱两种技术优势,同时它具有分析灵敏度高,干扰少,线性范围宽,可多元素同时测定等优点;在KBH4-酸还原体系中同时测定鱼肝中Hg和As,方法检出限分别为Hg:0.33ng/ml和As0.36ng/ml,线性范围分别为:0.1-2.0ng/ml和1.0-20.0ng/ml。加标回收率分别为Hg:96.0%和As:100.6%。分析结果可靠,方法令人满意,并适合大批量样品的分析。 相似文献