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61.
分析了煤种含硫量、灰份及粉尘化学组成对除尘效率的影响,研究了电除尘器效率考核存在的问题,提出了校核除尘效率的方法,并结合生产实际进行了核算。 相似文献
62.
An efficient, reproducible and rapid fused silica capillary column gas chromatographic method, in splitless mode, for analysing of the three chloroanthracene isomers is described. The method affords efficient separation and good linearity for each isomer in the range of 0.2 -200 μg/ml. The method can also be used in separation and determination of another thirty three aromatic and their halosubstituted compounds. This paper also presents the applications of the method in analysing of complex products mixture from reaction of the selected aromatic compounds with hydrogen chloride on fly ash surface from municipal incinerator. 相似文献
63.
利用合肥市臭氧和VOCs连续观测数据分析了合肥市臭氧及其前体物污染特征,并使用NAQPMS模型研究了合肥市不同季节臭氧来源情况。结果表明:O3已经成为影响合肥市环境质量的主要污染因子,O3高值区主要集中在5—6月和9月。合肥市大气VOCs中烷烃含量最丰富,其次是烯烃、芳香烃和炔烃;主要物种为乙烷、丙烷、乙炔、正戊烷、乙烯、环戊烷、异戊烷、正丁烷、异丁烷和甲苯。合肥市O3生成主要受VOCs控制,其中,烯烃是合肥市O3生成贡献最大的关键活性组分,乙烯的OFP贡献率居首位。合肥市不同季节O3来源差异较大,其中,本地排放是主要来源,夏季占比为50%,其余季节占比为30%~45%,O3存在跨省长距离输送特征,主导风向的变化是造成合肥市臭氧来源季节性变化的重要因素。 相似文献
64.
65.
The officer of the deck (OOD) of a US Navy ship is in charge of the safe and proper operation of the ship, and accountable to the commanding officer for every event that occurs during his or her OOD watch. This paper discusses the development of a prototype behavioral marker system to evaluate, and provide feedback on, the nontechnical (cognitive, social, and personal resource) skills of OODs.An initial set of 17 categories of nontechnical skills were identified from a literature review. A focus group with four qualified OODs used the skills identified from the literature review to develop an initial taxonomy of five categories, each with two or three corresponding behavioral elements. This taxonomy was then used to classify 149 statements concerned with the nontechnical skills of OODs collected from 16 critical incident interviews. After three iterations of adaptations to the taxonomy, two independent raters were able to reach acceptable levels of reliability in using the taxonomy to classify the statements. Although further development work is required, it is suggested that the prototype behavioral marker system has implications for improving safety and performance on military and civilian ships. 相似文献
66.
评述了典型认知模型及其在人因可靠性分析中的应用.首先,强调了在人因可靠性分析中使用认知模型的必要性; 然后,介绍了认知心理学、行为科学等学科所建立的几种典型认知模型,包括信息处理模型、决策过程的阶梯模型和通用认知模型,分别分析了它们的基本结构和功能,讨论了各自的优缺点; 随后,介绍了几种人因可靠性分析方法中所建立或使用的认知模型,包括HCR方法使用的SRK框架、ATHEANA方法使用的信息处理模型、CREAM方法建立的COCOM模型以及IDAC方法构建的IDA模型,分别分析了这些模型的特点; 最后,提出了建立认知模型所要遵循的基本原则,并展望了认知模型的未来发展方向. 相似文献
67.
Simulation of soil loss processes based on rainfall runoff and the time factor of governance in the Jialing River Watershed,China 总被引:1,自引:0,他引:1
Jialing River is the largest tributary in the catchment area of Three Gorges Reservoir, and it is also one of the important
areas of sediment yield in the upper reaches of the Yangtze River. In recent years, significant changes of water and sediment
characteristics have taken place. The "Long Control" Project implemented since 1989 had greatly changed the surface appearance
of the Jialing River Watershed (JRW), and it had made the environments of the watershed sediment yield and sediment transport
change significantly. In this research, the Revised Universal Soil Loss Equation was selected and used to predict the annual
average amount of soil erosion for the special water and sediment environments in the JRW after the implementation of the
"Long Control" Project, and then the rainfall–runoff modulus and the time factor of governance were both considered as dynamic
factors, the dynamic sediment transport model was built for soil erosion monitoring and forecasting based on the average sediment
yield model. According to the dynamic model, the spatial and temporal distribution of soil erosion amount and sediment transport
amount of the JRW from 1990 to 2007 was simulated using geographic information system (GIS) technology and space-grid algorithm.
Simulation results showed that the average relative error of sediment transport was less than 10% except for the extreme hydrological
year. The relationship between water and sediment from 1990 to 2007 showed that sediment interception effects of the soil
and water conservation projects were obvious: the annual average sediment discharge reduced from 145.3 to 35 million tons,
the decrement of sediment amount was about 111 million tons, and decreasing amplitude was 76%; the sediment concentration
was also decreased from 2.01 to 0.578 kg/m3. These data are of great significance for the prediction and estimation of the future changing trends of sediment storage
in the Three Gorges Reservoir and the particulate non-point source pollution load carried by sediment transport from watershed
surface. 相似文献
68.
69.
Hui Zhou Aihong Meng Yanqiu Long Qinghai Li 《Journal of the Air & Waste Management Association (1995)》2014,64(5):597-616
Municipal solid waste (MSW) has been normally sorted into six categories, namely, food residue, wood waste, paper, textiles, plastics, and rubber. In each category, materials could be classified further into subgroups. Based on proximate and ultimate analysis and heating value, statistical methods such as analysis of variance (ANOVA) and cluster analysis were applied to analyze the characteristics of MSW in every subgroup and to try to distinguish their relative properties. The chemical characteristics analysis of MSW showed that polyethylene (PE), polypropylene (PP), and polystyrene (PS) had the highest volatile matter content, with almost no ash and fixed carbon, while polyethylene terephthalate (PET) had high carbon content but low hydrogen content. Bones and vegetables had the highest ash content, while nutshells and rubber had the highest fixed carbon content. Paper and starch food had the highest oxygen content, and wool and bones had the highest nitrogen and sulfur content. Polyvinyl chloride (PVC) had the highest chlorine content at about 55%. PE, PP, and PS had the highest heating value, followed by chemical products such as rubber and chemical fiber. Conversely, paper, vegetables and bones had the lowest heating value. The results of cluster analysis of MSW components showed that fruit peel, weeds, wood, bamboo, leaves and nutshells could be classified as the lignocellulose category; starch food, cotton, toilet paper, printing paper and cardboard could be classified as the glucose monomer category; wood and chemical fiber could be classified as the high nitrogen and sulfur category; and PE, PP, and PS could be cluster as the polyolefin category.
Implications: The yield of municipal solid waste (MSW) is constantly increasing and waste to energy (WTE) has been used extensively all over the world. During the processes of incineration, pyrolysis, or gasification, the impact of physical and chemical properties of MSW is of great significance. However, the traditional classification of MSW is too general to provide more detailed information in many investigations. It is necessary to perform the investigation of characteristics of combustible MSW to distinguish different categories of MSW and find out their subclassification. 相似文献
70.
A two-dimensional numerical model for evaluating the wind flow and pollutant dispersion within a street canyon was first developed using the FLUENT code, which was then validated against a wind tunnel experiment. Then, the effects of the upstream building width and upwind building arrangement on the airflow and pollutant dispersion inside an isolated street canyon were investigated numerically. The numerical results revealed that: (1) the in-canyon vortex center shifts downwards as the upstream building width increases; (2) the recirculation zone covers the entire upstream building roof for the cases when W/H = 0.5, 1.0, 1.5, and 2.0 (W is the upstream building width and H is the building height), whereas the flow reattaches the upstream building roof for the cases when W/H = 2.5 and 3.0; (3) when the upstream building width is shorter than the critical width WC (= 2H), an increase in the upstream building width leads to an increase in the pollution level on the leeward wall of the canyon and a decrease in the roof-level concentrations at the upstream building; (4) when the upstream building width is longer than the critical width, the roof-level concentrations at the upstream building are negligibly small and the pollution level on the leeward wall of the canyon is almost unaffected by a further increase in the upstream building width; (5) when the buildings are placed upwind of the canyon, the flow attaches the upstream building roof and, therefore, almost none of the pollutants are distributed on the upstream building roof; and (6) the pollution levels inside the canyon and on the downstream building roof increase significantly with the number of upwind buildings. 相似文献