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831.
以乳化炸药螺杆泵为研究对象,画出系统功能方框图和可靠性方框图,应用故障模式及影响分析方法(FMEA),确定螺杆泵的各种可能故障模式、故障原因和故障影响。同时计算出各故障的风险度,并依次对故障进行分级,找出对螺杆泵危害严重的故障。最后建立FMEA表格,并根据分析结果提出提高其可靠性的建议措施。 相似文献
832.
建立了微波辅助提取,采用氢化物发生原子荧光光谱法不进行价态分离,直接测定土壤中As(Ⅲ)和As(Ⅴ)的方法。通过加入抗坏血酸作为抗氧化剂,以磷酸溶液、L-半胱氨酸分别为提取剂和还原剂,在不还原与还原两种情况下分别进行测量,根据荧光强度与As(Ⅲ)和As(Ⅴ)的质量浓度关系方程式计算提取液中它们的质量浓度。对实验条件进行优化后,As(Ⅲ)、As(Ⅴ)的方法检出限均可达到0.05μg.g-1,实验精密度(RSD,n=11)分别为1.3%和2.1%,样品加标平均回收率分别为As(Ⅲ)为93.2%~110.0%,As(Ⅴ)为92.6%~104.0%。该方法不需要高效液相色谱等大型设备、简单可靠、易于操作、分析速度快、精密度高,具有在各分析测试实验室推广应用价值。方法已用于实际土壤样品中不同价态无机砷质量分数的测定。 相似文献
833.
Khan Irfan Hou Fujun 《Environmental science and pollution research international》2021,28(5):5049-5062
Environmental Science and Pollution Research - We examine the impact of energy consumption and tourism growth on the ecological footprints and economic growth of 38 International Energy Agency... 相似文献
834.
以硫化砷渣为原料,用氯化铜酸性溶液浸出砷渣的全湿法进行实验,着重研究氯化铜浸出砷的过程中氯化铜用量、溶液p H和浸出时间对砷浸出率的影响,探讨用氯化亚锡还原砷盐酸溶液从硫化砷渣得到单质砷的方法。 相似文献
835.
836.
837.
Lifeng Zhang Jiangtian Hou Xiaotao Bi 《Journal of Loss Prevention in the Process Industries》2013,26(6):1328-1334
Electrostatic charges accumulated on wood particles through triboelectrification during their transportation and handling processes can cause hazardous electrical discharge which may further trigger dust explosion. In this work, tribo-charging behavior of different kinds of wood particles was investigated by a vibrating plate charging method. It was found that reduction in the work function difference between contact bodies might contribute to the reduction of tribo-charge generation, while the reduction of electrical resistivity of wood pellets could effectively accelerate the charge dissipation. As the particle size decreases, accumulated charges increase significantly. In contrast, higher moisture content of wood particles leads to lower charge accumulation due to an accelerated charge dissipation rate. Tribo-charging behaviors of white pellets, torrefied pellet, steam treated pellets and dark pellets have also been investigated. Compared to the white pellets, they all have shown a reduction on charge accumulation to some extent. However, results suggested that all of them have nearly equivalent tribo-charge density as coal and wheat grains used as references in this study. 相似文献
838.
Abstract Since the 1990s, the Yellow River stream has been temporarily interrupted for several years, which affects the development of society, the economy and human life, limits the economic potential of the drainage areas, and especially causes great harm to regions on the lower reaches. Based on the analysis of the relationship between the development of society and economy and water scarcity, the author thinks it is necessary to optimize and adjust the industrial structure that has extravagantly consumed enormous amounts of water, and to develop ecological agriculture, industry and tourism which are balanced with the ecological environment. Finally, the author puts forward several pieces of advice and countermeasures about how to build the economic systems by which water can be used economically. 相似文献
839.
Spatial assessment for groundwater quality based on GIS and improved fuzzy comprehensive assessment with entropy weights 总被引:1,自引:0,他引:1
Jingwei Hou 《中国人口.资源与环境(英文版)》2013,11(2):135-141
The objective of the research is to evaluate spatial groundwater quality based on improved fuzzy comprehensive assessment model with entropy weights(FCAEW)in geographical information system(GIS)environment.This paper explores the method of comprehensive evaluation of groundwater and sets up an evaluation model applying GIS and FCAEW.Groundwater samples were collected and analyzed from 29 wells in Zhenping County,China.Six parameters were chosen including chloride,sulfate,total hardness,nitrate,fluoride and color.Better spatial interpolation methods for evaluated parameters are found out and selected according to the minimum cross-validation errors from the interpolation methods.FCAEW model was carried out with the help of GIS which makes the evaluating process simpler and easier and more automatically,effectively,efficiently and intelligently.The result embodies the feasibility and effectiveness of FCAEW in GIS when compared with other comprehensive evaluation methods. 相似文献
840.
Fabrication and performance of PET mesh enhanced cellulose acetate membranes for forward osmosis 总被引:1,自引:0,他引:1
Polyethylene terephthalate mesh(PET) enhanced cellulose acetate membranes were fabricated via a phase inversion process. The membrane fabrication parameters that may affect the membrane performance were systematically evaluated including the concentration and temperature of the casting polymer solution and the temperature and time of the evaporation, coagulation and annealing processes. The water permeability and reverse salt flux were measured in forward osmosis(FO) mode for determination of the optimal membrane fabrication conditions. The optimal FO membrane shows a typical asymmetric sandwich structure with a mean thickness of about 148.2 μm. The performance of the optimal FO membrane was tested using 0.2 mol/L Na Cl as the feed solution and 1.5 mol/L glucose as the draw solution. The membrane displayed a water flux of 3.47 L/(m2·hr) and salt rejection of95.48% in FO mode. While in pressure retarded osmosis(PRO) mode, the water flux was4.74 L/(m2·hr) and salt rejection 96.03%. The high ratio of water flux in FO mode to that in PRO mode indicates that the fabricated membrane has a lower degree of internal concentration polarization than comparable membranes. 相似文献