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191.
192.
MapInfo是目前流行的地理信息系统 (GIS)应用软件之一 ,由于其强大的地图功能 ,在地震监测预报中得到了越来越广泛的应用。安徽省地震局合肥遥测台网不久前完成了台网自己的速报软件的开发研制工作 ,其中运用了MapInfo部分图形操作功能。本文介绍MapInfo技术在台肥遥测台网地震速报中的一些具体应用 相似文献
193.
A. N. Papanicolaou A. Bdour N. Evangelopoulos N. Tallebeydokhti 《Journal of the American Water Resources Association》2003,39(1):191-203
ABSTRACT: This paper presents the results of a statistical analysis performed for the watershed and stream corridor in the South Fork of the Clearwater River (SFCR) basin, in north central Idaho. The analysis was performed for 61 six‐field hydrological unit codes (HUCs) of the SFCR basin using an extensive record (up to 100 years) for 50 watershed and in‐stream parameters, including hydrologic, flow, fish, anthropogenic, and natural activity data. The objective of this research was twofold: first, the development of quantitative relations that describe the Index of Fish Density (IFD) of particular fish species as a function of watershed and instream parameters; and second, to provide a robust confirmation for the effects of some of these parameters, previously recorded by the fisheries profession, by using well established statistical techniques. The uniqueness of this work is the compilation and statistical analysis of large data sets to quantitatively describe the impacts of watershed and instream parameters on the IFD of all salmonids and specific fish species. Factor analysis was employed to regroup parameters that are highly correlated to each other into a set of single factors and to relate the IFD to these factors. Using factor extraction, 12 factors were developed from the 50 watershed and instream parameters. Multiple regression diagnostic tests indicated that only 7 of the 12 factors are strong predictors offish indicators. The strongest predictors are longitude, latitude, elevation, watershed gradient, and water temperature. The analysis indicated that the present model has reasonable predictive power, considering the uncertainty involved in estimating the interdependence of IFD with watershed parameters. 相似文献
194.
粉煤灰静电脱炭技术研究 总被引:1,自引:0,他引:1
本文介绍粉煤灰静电脱炭资源化利用技术的试验研究.利用YNDF-I型立式电场粉煤灰脱炭装置进行优化试验,提出电压、极板间距、摩擦分散器材料、粉尘浓度及气体流量等运行工艺特性参数与静电脱炭率的相关关系.试验结果表明,该立式电场脱炭装置在最优工艺参数条件下运行时,可使粉煤灰脱炭后的精灰含炭量降低到1.20%,脱炭率达86.74%,能够直接代替水泥用作建筑材料或修筑公路路面,具有较高的经济效益、社会效益和环境效益,为粉煤灰资源化利用提供了一种新的途径. 相似文献
195.
液相络合-铁粉还原-酸吸收回收法脱除烟气中NO 总被引:8,自引:0,他引:8
提出了Fe2+螯合剂络合-铁粉还原-酸吸收回收法脱除烟气中NO的新工艺,重点研究了模拟烟气中O2含量对NO络合量的影响,以及铁粉用量、铁粉粒径和搅拌速度对脱氮效率的影响,确定了最佳的铁粉脱氮工艺条件,并对铁粉和铁屑的脱氮效果进行了比较.结果表明:烟气中φ(O2)从0增加到4.2%,NO络合量下降90.2%;脱氮效率随铁粉用量和反应器搅拌速度的增加而增加,随铁粉粒径的增加而降低;最佳工艺参数为,铁粉用量0.8 g,铁粉粒径≥200目(≤0.077 mm),搅拌速度900 r/min,在该条件下,对φ(O2)为5%的模拟烟气在搅拌反应器中可取得90%以上的脱氮效率;用铁粉在1台搅拌反应器中取得的脱氮效率和用铁屑在2个鼓泡反应器串联时所取得的效率相当. 相似文献
196.
The monitoring of surface water quality of rivers is crucial to protect aquatic life and receiving water bodies of economic importance. The aim of the current study was to examine selected physicochemical parameters of River Tajan due to its ecological importance in Iran. Water samples from nine points covering the entire Tajan River and Caspian Sea estuary were collected and analyzed for pH, electrical conductivity (EC), total dissolved solids (TDS), carbonates, chlorides and selected heavy metals including zinc, cadmium, lead and chromium. The pH and levels of EC, TDS, chlorides, carbonates and all metals were within the USEPA reference guidelines for surface water quality standards. Although these water quality parameters are considered safe, continuous monitoring and assessment is recommended in order to protect the coastal receiving waters of Caspian Sea which serves as a tourist attraction in northern Iran. 相似文献
197.
Assessment of seasonal variations of carbon dioxide concentration in Iran using GOSAT data
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Seyed Mohsen Mousavi Samereh Falahatkar Manouchehr Farajzadeh 《Natural resources forum》2017,41(2):83-91
Global warming and climate change have been identified as the most important challenges of the 21st century. Greenhouse Gases Observation Satellite (GOSAT) measures the concentrations of carbon dioxide (CO 2) and methane (CH 4) in the atmosphere column from the earth's surface to the upper atmosphere. In this research, GOSAT Thermal And Near Infrared Sensor for Carbon Observation – Fourier Transform Spectrometer (TANSO‐FTS) level 2 data and meteorological parameters were used in the assessment of changes in CO 2 concentration (XCO 2) from 2009 to 2015. We investigated the relationship between XCO 2 and meteorological parameters (temperature and precipitation) obtained from weather stations and the Normalized Difference Vegetation Index (NDVI) in the year 2013 in Iran. The results reveal a steady increase in the mean atmospheric CO 2 concentration, from 384.89 to 400.39 ppm. It was observed that the XCO 2 varied significantly depending on the month, with the highest concentration of CO 2 in April/May and the lowest concentration in August/September. The correlation between XCO 2 and average monthly air temperature is negative, which means that a reduction in XCO 2 with an increase in temperature is dependent on photosynthetic activities in the growing seasons. The highest and lowest correlation coefficient between the NDVI and XCO 2 was obtained in the spring and in the fall, respectively. These findings are useful for recognizing factors that affect CO 2 concentration in different seasons in arid and semi‐arid regions, and as an initial step toward sustainable management. 相似文献
198.
为了预测汽车排放污染物的浓度,应用简化的高斯烟团模式得到静风条件下的线源扩散预测模式。并结合高斯烟流扩散模式,建立了预测汽车污染物在任意风向下和年平均浓度的预测模式,考虑车道上存在车辆行驶的强烈机械扰动湍流和把繁忙的公路视为线源两个因素,提出了计算初始扩散参数的方法。然后,运用Turner和Pasquill扩散参数,建立了线源扩散参数的确定方法。该模式应用于预测高速公路沿途汽车污染物的浓度表明,计算值与监测值吻合较好,可用于我国公路环境影响的评价。 相似文献
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200.