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541.
Underground coal mine explosions is perhaps the most hazardous danger in the coal mining industries. Efforts have been made to abate the coal dust explosion by applying rock dust either dry or wet. Dry dust has the best lift characteristic which efficiently quenches the flame propagation of a potential explosion. As a trade-off, undesired respirable dust particles are thereby generated imposing a severe health hazard on coal miners. Wet dusting is an alternative to dry dusting which significantly reduces the exposure to respirable dust particles. However, wet dust is subject to adverse caking issues which lead to a drastic reduction in the dispersibility of the particles. The present work summarizes the studies conducted to date regarding the surface modification of rock dust particles for the purpose of eliminating or alleviating the problems accompanying coal mine dusting applications, meanwhile improving the dispersive properties of dust particles and the ability to suppress the coal dust explosion. 相似文献
542.
543.
成都冬季典型辐射逆温过程分析 总被引:1,自引:0,他引:1
本文利用测温声雷达的探测结果,借助同期探空和地面观测资料,分析了成都平原典型辐射逆温的生消演变规律,指出了其主要特征。这些结果对气候资源利用、污染气象条件的研究等具有重要意义。 相似文献
544.
介绍了国外有关腐蚀性空气环境的分级标准及其检测方法。环境中的腐蚀性气体可对电子元器件及自动控制设备产生腐蚀,影响其性能。根据腐蚀性的严重程度,美国仪器学会标准中将腐蚀性空气环境分为四级。环境腐蚀性置于腐蚀性环境中的铜试条进行检测。 相似文献
545.
化工厂排放SO2对周围植物的影响 总被引:6,自引:0,他引:6
对某厂区及常年盛行风下风向地区植物受SO2危害情况进行了调查,并测定了部分植物叶片中的硫含量。从植物叶片中的硫含量可间接地判断大气被SO2污染的程度及植物对SO2吸收与抵抗能力的强弱。 相似文献
546.
氧化镁法脱硫,具有工艺流程短、脱硫效率高等优点,对控制烟气SO2造成的大气污染是一种行之有效的办法,具有推广应用的广阔前景。 相似文献
547.
Veerasamy Kothandaraman Ralph L. Evans 《Journal of the American Water Resources Association》1981,17(4):607-613
: Chemical quality characteristics of the Illinois waterway covering a stretch of 270 river miles were monitored at approximately 10 mile intervals, during the period June to September of 1978 and 1979. A statistical method was used to define the interstation relationships for the chemical parameters. These mathematical models were used to predict the effects of Lake Michigan diversion. The mineral content of the mixed flow resulting from increased diversions are not likely to be altered drastically. 相似文献
548.
Atmospheric reaeration is a natural mechanism of oxygen transfer from the atmosphere to a water body. In practice, stream water quality models are developed with reaeration coefficients (K2) estimated by predictive equations. This leads to uncertainties in modeling analysis because these equations are empirical in nature and may yield greatly different K2 values for the same stream. Values of K2 may be adjusted in model calibration, but unfortunately, values of other model parameters are no less easy to identify and require adjustment in model calibration as well. Therefore, validity of a stream model would be enhanced significantly if K2 could be determined directly and reliably. In this research, values of K2 in the Canandaiqua Outlet in Central New York have been measured by using a gas tracer method. A successful modeling analysis was conducted using these K2 values. As a result, effluent limitations of several waste water discharges into the Outlet were established. It was concluded that field measurements of reaeration rate would improve modeling results significantly, and that the gas tracer method can be easily incorporated into intensive water quality surveys normally required for stream modeling. 相似文献
549.
Carl D. Settergren Larry C. Tennyson 《Journal of the American Water Resources Association》1979,15(5):1353-1364
ABSTRACT: A number of criteria can be used in the selection of an area for the irrigation disposal of secondary treated waste water. The inherent capacity of the surface soil to retain, or at least detain, the various nutrient ions passing through the profile in the percolating waters becomes the prime consideration in regions with shallow water tables or in Karst areas such as the Missouri Ozarks where the risk of ground water supply contamination is high. A comprehensive study of the nutrient renovation potential of several soils was undertaken at a proposed effluent irrigation site along the Ozark National Scenic Riverways in south central Missouri. The surface soil hydrology was evaluated employing selected soil water parameters. Exchange equilibria studies determined the retention capacity for Ca and Mg while the concentrations of other selected ions were analyzed in the soil water to measure their retention time and net removal. The movement of a bromine tracer was monitored as an index of the renovation capacity of these soils for the more mobile anions such as nitrate. Neutron activation analysis proved to be a useful tool in the water quality analyses. All surface soil profiles demonstrated some degree of nutrient renovation for the various nutrients studied. 相似文献
550.