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21.
A study on the orbit of air temperature movement   总被引:1,自引:0,他引:1  
In this paper, we describe an air temperature movement by mapping its time series to the polar coordinates: the value of the time series is plotted on the radial coordinate and the time on the angular coordinate. In this way, both the yearly and daily air temperature movements from five different locations of China are used to demonstrate that, in an intuitionistic view, air temperature movement is neither random nor chaotic, but has its own orbit. We then propose an elliptic orbit model for the air temperature movement. Our proposed model provides quite good results when it is applied to the evaluation of yearly air temperature movements in eight locations in various parts of the world, and the evaluation of daily air temperature movements in five locations in Hunan Province of China on December 17, 2005. Results show that our approach provides a concise and helpful model for air temperature analysis.  相似文献   
22.
A distributed hydrologic modeling and GIS approach is applied for the assessment of land use impact in the Steinsel sub-basin, Alzette, Grand-Duchy of Luxembourg. The assessment focuses on the runoff contributions from different land use classes and the potential impact of land use changes on runoff generation. The results show that the direct runoff from urban areas is dominant for a flood event compared with runoff from other land use areas in this catchment, and tends to increase for small floods and for the dry season floods, whereas the interflow from forested, pasture and agricultural field areas contributes to the recession flow. Significant variations in flood volume, peak discharge, time to the peak, etc., are found from the model simulation based on the three hypothetical land use change scenarios.  相似文献   
23.
Large, complex energy models present considerable challenges to develop and test. Uncertainty assessments of such models provide only partial guidance on the quality of the results. We have developed a model quality assistance checklist to aid in this purpose. The model checklist provides diagnostic output in the form of a set of pitfalls for the model application. The checklist is applied here to an energy model for the problem of assessing energy use and greenhouse gas emissions. Use of the checklist suggests that results on this issue are contingent on a number of assumptions that are highly value-laden. When these assumptions are held fixed, the model is deemed capable of producing moderately robust results of relevance to climate policy over the longer term. Checklist responses also indicate that a number of details critical to policy choices or outcomes on this issue are not captured in the model, and model results should therefore be supplemented with alternative analyses.  相似文献   
24.
内蒙古发展循环经济的方向与政策初探   总被引:1,自引:0,他引:1  
本文从内蒙古资源、经济与环境问题现状出发,分析了发展循环经济的必要性、紧迫性和可行性,提出了我区建立循环经济的发展战略应考虑的基本原则,发展方向和法律、政策方面的建议。  相似文献   
25.
硫酸法钛白生产水洗工序清洁生产技术初探   总被引:1,自引:0,他引:1  
通过开展水洗工段用水审计并试验了温度、偏钛酸ξ电位和漂白工艺对水洗的影响效果,从实践和理论上探讨了为其提高钛白质量改进水洗工艺的清洁生产方案的可行性和合理性。  相似文献   
26.
本文研究了混凝沉淀工艺处理矿井水中天然总α放射性核素铀、镭的技术和条件,通过选择适当的混凝剂、加药量、pH值等条件可将铀的去除率提高到80%左右,使用铀专用混凝剂MHU则可使铀的去除率达到87%。对于镭的去除不能单纯依靠铀混凝剂MHU,尚需添加镭的吸附助剂MHR,则可使镭的去除率提高到80%以上。该工艺的最大优点在于充分利用了煤矿现存的大量矿井水悬浮物处理设施,大大节省了新建工程的投资费用,而且新增加的药剂费用不足0.1元/t水,可在煤矿推广应用。  相似文献   
27.
说到“美食与环保”,人们自然会想到健康食品、无公害食品、绿色食品、自然食品、有机食品之类的标签,脑子里浮现出“土鸡(广东称走地鸡)”、“柴鸡蛋”等鲜活的形象。没污染、低农药残留甚至不施用农药、用农家肥而不是化肥,散养而非圈养等是其获得以上标签的要件。似乎关注环保,食品自然美味。  相似文献   
28.
利用上限元技术(UBET)模拟出薄壁深孔件在变薄拉深成形过程中,几种主要工艺参数对断裂的影响程度,由此得出防止断裂产生的措施。  相似文献   
29.
管式塑料烧结微孔曝气器在炼油污水处理中的应用   总被引:1,自引:0,他引:1  
在吸附再生装置中使用管式塑料烧结微孔曝气器,氧利用率高,动力效率高,服务面积大,布气均匀,耐各种负荷冲击。  相似文献   
30.
Using a case study of the Lake Abitibi Model Forest (LAMF), this study aims to assess the temporal and spatial variability in carbon storage during 1990–2000, and to present a comprehensive estimation of the carbon budget for LAMF's ecosystems. As well, it provided the information needed by local forest managers to develop ecological and carbon-based indicators and monitor the sustainability of forest ecosystems. Temporal and spatial carbon dynamics were simulated at the landscape level using ecosystem model TRIPLEX1.0 and Geographical Information System (GIS). The simulated net primary productivity (NPP) and carbon storage in forest biomass and soil were compared with field data and results from other studies for Canada's boreal forests. The results show that simulated NPP ranged from 3.26 to 3.34 tC ha−1 yr−1 in the 1990s and was consistent with the range measured during the Boreal Ecosystem-Atmosphere Studies (BOREAS) in central Canada. Modeled NPP was also compared with the estimation from remote sensing data. The density of total above-and belowground biomass was 125.3, 111.8, and 106.5 tC ha−1 for black spruce, trembling aspen, and jack pine in the LAMF ecosystem, respectively. The total carbon density of forested land was estimated at 154.4 tC ha−1 with the proportion of 4:6 for total biomass and soil. The analysis of net carbon balance of ecosystem suggested that the LAMF forest ecosystem was acting as a carbon sink with an allowable harvest in the 1990s.  相似文献   
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