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771.
目的研究吊篮在离心载荷下的力学行为,尤其是强度和刚度性能。方法通过精细化模拟吊篮系统各部件间的接触关系,在对某离心机吊篮初始设计方案进行模拟分析的基础上,开展吊篮的强度性能研究,对吊篮结构的整体布局、主要部件强度考核和降低局部应力集中等多方面开展计算分析。结果在指定工况下吊耳与配重板之间的局部接触导致的应力集中,致使安全系数达不到强度要求。结论提出改进措施,改进设计后的吊篮结构强度得到了较大的提高,满足吊篮设计的强度要求。  相似文献   
772.
从铅蓄电池的生产工艺及产污环节出发,就清洁生产、废气治理、废水治理、危废管理、卫生防护和运行监管等方面提出铅污染防治技术及措施。  相似文献   
773.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). The wire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g.  相似文献   
774.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). Thewire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g.  相似文献   
775.
As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission (GHG), and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment (LCA). Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO2-equivalent (CO2-eq.), 4.43 kg SO2-eq., 4.88 kg NO3--eq., and 3509 m3 water per ton tourist waste were found to be released in terms of global warming (GW), acidification (AC), nutrient enrichment (NE) and spoiled groundwater resources (SGWR), respectively. The total GHG emission was around 3499 ton CO2-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO2-eq., and CH4, CO and other hydrocarbons (HC) were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton CO2-eq. savings could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective.  相似文献   
776.
NOx emissions from biogenic sources in soils play a significant role in the gaseous loss of soil nitrogen and consequent changes in tropospheric chemistry. In order to investigate the characteristics of NOx fluxes and factors influencing these fluxes in degraded sandy grasslands in northern China, diurnal and spatial variations of NOx fluxes were measured in situ. A dynamic flux chamber method was used at eight sites with various vegetation coverages and soil types in the northern steppe of China in the summer season of 2010. Fluxes of NOx from soils with plant covers were generally higher than those in the corresponding bare vegetation-free soils, indicating that the canopy plays an important role in the exchange of NOx between soil and air. The fluxes of NOx increased in the daytime, and decreased during the nighttime, with peak emissions occurring between 12:00 and 14:00. The results of multiple linear regression analysis indicated that the diurnal variation of NOx fluxes was positively correlated with soil temperature (P < 0.05) and negatively with soil moisture content (P < 0.05). Based on measurement over a season, the overall variation in NOx flux was lower than that of soil nitrogen contents, suggesting that the gaseous loss of N from the grasslands of northern China was not a significant contributor to the high C/N in the northern steppe of China. The concentration of NOx emitted from soils in the region did not exceed the 1-hr National Ambient Air Quality Standard (0.25 mg/m3).  相似文献   
777.
Fe2+S2O82-EDTA体系中自由基离子对啶虫脒的氧化降解   总被引:1,自引:0,他引:1  
为探讨水环境中自由基离子对啶虫脒的共降解作用,研究了Fe2+S2O82-EDTA体系中啶虫脒降解的可行性,以及在Fe2+S2O82-EDTA体系中3种组分最佳配比条件下自由基离子和底物浓度对啶虫脒降解率的影响.结果表明,在Fe2+S2O82-EDTA体系下反应360 min后啶虫脒的降解率达到58.25%,c(Fe2+)、c(S2O82-)和c(EDTA)对Fe2+S2O82-EDTA体系的氧化能力均有较大的影响.通过中心复合试验对Fe2+S2O82-EDTA体系中3种离子的最佳配比进行优化,c(EDTA)、c(Fe2+)、c(S2O82-)分别为1.61、3.46、7.99 mmolL.Fe2+S2O82-EDTA体系中·SO4-和·OH等自由基离子的存在是引起啶虫脒降解的主要原因,中性条件最有利于自由基离子的产生并提高啶虫脒高的降解率.然而该体系中自由基离子的量是一定的,过高的c(啶虫脒)(200μmolL)对降解率有明显抑制.  相似文献   
778.
To utilize visible light more effectively in photocatalytic reactions, a fly ash cenosphere (FAC)-supported CeO2-BiV04 (CeO2-BiVO4/FAC) composite photocatalyst was prepared by modified metalorganic decomposition and impregnation methods. The physical and photophysical properties of the composite have been characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and UV-Visible diffuse reflectance spectra. The XRD patterns exhibited characteristic diffraction peaks of both BiVO4 and Ce02 crystalline phases. The XPS results showed that Ce was present as both Ce4+ and Ce3+ oxidation states in Ce02 and dispersed on the surface of BiV04 to constitute a p-n heterojunction composite. The absorption threshold of the CeO2-BiVO4/FAC composite shifted to a longer wavelength in the UV-Vis absorption spectrum compared to the pure Ce02 and pure BiV04. The composites exhibited enhanced photocatalytic activity for Methylene Blue (MB) degradation under visible light irradiation. It was found that the 7.5 wt.% CeO2-BiVO4/FAC composite showed the highest photocatalytic activity for MB dye wastewater treatment.  相似文献   
779.
环保能力建设是环境规划的重要组成部分。物联网作为信息技术的深度拓展应用,在国家和山西省的环境保护“十二五”规划中都提出要推进物联网技术在环保领域的应用,加强环保监管能力建设。本文研究分析了山西省环保监管能力建设现状与需求,围绕环保物联网的三层技术架构和三条业务主线构建了山西省环保物联网建设的总体框架,实现了三个方面的环境管理创新。环保物联网建设对于进一步推动我省环保能力建设向科学化、精细化和智能化转变,实现“十二五”乃至“十三五”环境规划战略目标具有重要意义。  相似文献   
780.
目的基于实测的海洋资料,研究设计海洋内孤立波诊断模型。方法首先对实测的ADCP海洋资料和温度链资料进行质量控制处理,然后利用海洋内波动力学理论和诊断分析技术,建立提取海洋内波特征的诊断模型。结果成功设计了能够提取海洋内波振幅、内波周期、变差流矢量时间序列、内波波致流和内波传播方向的诊断模型。结论该诊断模型通过实测的温度链、潜标、ADCP等连续观测的海洋资料,可诊断出海洋内波周期、内波振幅等特征要素,为实施海洋水文气象保障提供了重要技术手段。  相似文献   
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