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481.
针对电除尘器在运行中出现的问题,利用大小修的机会,先后对电除尘器采取了一些必要的改造措施,达到了提高电除尘器收尘效果和可靠性的目的。 相似文献
482.
通过对某型号卫星贮箱支架的数控加工实践,研究了大型铝合金框架式薄壁结构件的高效数控加工工艺技术。通过合理选择机械加工规程和工艺参数,解决了这类零件加工过程中极易超差等难题,可靠地满足了型号研制的要求。同时利用MastercamX软件研究了高效数控加工问题。 相似文献
483.
陆东庭 《安全.健康和环境》2009,9(1):19-21
分析了蒸馏装置减压塔进料接管角焊缝开裂、泄漏原因,阐述了减压转油线冷紧的重要性及检修中应注意的问题。 相似文献
484.
In an urban-transit bus,fueled by biodiesel in Toledo,Ohio,single inhalable particle samples in October 2008 were collected and detected by scanning electron microscopy and energy dispersive X-ray spectrometry(SEM/EDS).Particle size analysis found bimodal distribution at 0.2 and 0.5 μm.The particle morphology was characterized by 14 different shape clusters:square,pentagon,hexagon,heptagon,octagon,nonagon,decagon,agglomerate,sphere,triangle,oblong,strip,line or stick,and unknown,by quantitative order.The square particles were common in the samples.Round and triangle particles are more,and pentagon,hexagon,heptagon,octagon,nonagon,decagon,strip,line or sticks are less.Agglomerate particles were found in abundance.The surface of most particles was coarse with a fractal edge that can provide a suitable chemical reaction bed in the polluted atmospheric environment.The three sorts of surface patterns of squares were smooth,semi-smooth,and coarse.The three sorts of square surface patterns represented the morphological characteristics of single inhalable particles in the air inside the bus in Toledo.The size and shape distribution results were compared to those obtained for a bus using ultra low sulfur diesel. 相似文献
485.
The sludge, which was collected from a biological coke wastewater treatment plant, was used as a low-cost adsorbent in the removal of reactive dyes (methylene blue (MB) and reactive red 4 (RR4)) from aqueous solution. The pH of dye solution played an important role on the dye uptake. As the solution pH increase, the MB uptake increased, while the RR4 uptake decreased. The maximum uptake of RR4 by protonated sludge was 73.7 mg/g at pH 1, and the maximum uptake of MB by sludge was 235.3 mg/g at pH 9. Three functional groups, including carboxyl, phosphonate, and amine group, were identified by potentiometric titration, fourier transform infrared (FT-IR) spectrometry, and X-ray photoelectron spectroscopy (XPS). The anionic functional groups, phosphonate and carboxyl group, were identified as the binding sites for the cationic MB. Amine groups were identified to bind RR4. The main mechanism of the reactive dyestuffs adsorption is electrostatic interaction. 相似文献
486.
通过对不同土壤环境标准物质和留样进行实测比对,验证了不同品牌的便携式X荧光光谱仪在不同样品情况下的工作性能,然后根据测试结果的准确度、精密度、可比性和仪器的辐射安全性优选出可用的仪器品牌;并对便携式X荧光光谱仪在土壤监测中存在的问题进行了探讨。 相似文献
487.
488.
-PbO2 electrodes were prepared by electro-deposition and characterized by scanning electron microscopy, X-ray diffraction, X-ray
photoelectron spectroscopy, and linear sweep voltammetry. We confirmed pure -PbO2 crystals were on the electrode and it had a high
oxygen evolution potential. The photoactivity and photoelectrochemical (PEC) properties of the -PbO2 electrode were investigated
under visible light irradiation ( > 420 nm) for the decolorization of Methylene Blue. Pseudo first-order kinetics parameter (Kapp) for
dye decolorization using the -PbO2 electrode achieved 6.71×10?4 min?1 under visible light irradiation, which indicated its excellent
visible light-induced photoactivity. The Kapp of the PEC process was as much as 1.41×10?3 min?1 and was 1.71 times that of visible light
irradiation or electrolysis even in the presence of the -PbO2 electrode. A significant synergetic effect was observed in the PEC system.
We also employed TiO2 modified -PbO2 electrodes in this test, which revealed that the TiO2 immobilized on the -PbO2 electrode
inhibited the visible light-induced PEC efficiency despite the amount of TiO2 used for electrode preparation. The -PbO2 electrode was
also superior to the dimensionally stable anode (Ti/Ru0:3Ti0:7O2) in visible light-induced photoactivity and PEC efficiency. 相似文献
489.
Computing payment for ecosystem services in watersheds: An analysis of the Middle Route Project of South-to-North Water Diversion in China 总被引:1,自引:0,他引:1
Zhengju Dong Yan Yan Jing Duan Xiao Fu Qingrong Zhou Xiang Huang Xiangen Zhu Jingzhu Zhao 《环境科学学报(英文版)》2011,23(12):2005-2012
An improved watershed criteria model was developed in light of research on payment for ecosystem services outflows theory. 相似文献
490.