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821.
Donald Rundquist Gene Murray Lloyd Queen 《Journal of the American Water Resources Association》1985,21(6):989-994
The Sandhills region represents a tremendous water resource for the State of Nebraska. Small shallow lakes, marshes, and subirrigated meadows are abundant due to interactions between ground water and surface water. One theory relating ground water to lake-flow systems in the Sandhills has been termed the “flow-through” concept. Thermal-infrared remotely acquired images document the flow-through model for a test site in Western Nebraska. 相似文献
822.
Mike S. Brewer Richard Lee J. David Helvey 《Journal of the American Water Resources Association》1982,18(5):755-759
ABSTRACT: Data from a small forested catchment were used to model peak stream flow as a function of basic hydrologic variables associated with 112 rain storms. Rainfall depth and initial stream flow rate accounted for 87.1 percent of peak flow variability. Forty expressions of rainfall intensity (describing both the temporal sequence of intensity for 20 equal storm intervals, and maximum intensity for 20 separate interval lengths) were used in an attempt to improve the predictability of basic models. None of the intensity parameters improved predictability by as much as 2 percent, apparently because the most intense rainfall bursts generally occurred near the beginning of storm periods. Mean rainfall intensity for entire storms was generally as effective as any of the shorter interval intensities, and its use helped to linearize the relationship between peak flow and rainfall depth and duration. 相似文献
823.
824.
本文从环境保护角度分析了氯化物对环境的影响。从而提出了制订“气田水中氯化物含量排放标准”的建议,讨论了气田水的处理方法。 相似文献
825.
Robert D. Jarrett Loren W. Crow 《Journal of the American Water Resources Association》1988,24(3):615-626
ABSTRACT: An evaluation of the Leadville, Colorado, precipitation records that include a reported record-breaking storm (and flood) at higher elevations in the Rocky Mountains has indicated that the use of an experimental Marvin windshield (designed to decrease the effects of wind on precipitation-gage catchment of snow during winter) resulted in substantially overregistered summer precipitation for 1919 to 1938. The July monthly precipitation for these years was over-registered by an average of 157 percent of the long-term July monthly precipitation at Leadville. The cause of the overregistration of precipitation was the almost 4-foot-top-diameter cone-shaped windshield that had the effect of “funneling” hail and rain splash into the rain gage. Other nearby precipitation gages, which did not use this Marvin windshield, did not have this trend of increased precipitation for the same period. Streamflow records from the Leadville area also do not indicate an increase in streamfiow from 1919 to 1938. The storm of July 27, 1937, considered one of the few, large, intense rainstorms at higher elevations, had a recorded precipitation of total 4.34 inches (4.26 inches in 1 hour). Streamflow-gaging-station records indicate that only 0.09 inch of storm runoff occurred. Paleoflood investigations of channels in the Leadville area and old newspaper accounts also indicate no substantial flood from this storm. This study indicates that the 1937 storm probably totaled about 1.7 inches of precipitation, much of which occurred as hail. 相似文献
826.
为解决医疗行业废物排放量核定难的问题,通过对医疗机构废物产生量的调查、统计、分析,在确定医疗废物排放统计变量的基础上,得出相应的医疗废物排放系数,以供排污申报医疗废物排放量的核定。 相似文献
827.
828.
829.
非平衡放电等离子体治理有害气体 总被引:17,自引:0,他引:17
重点分析了常温常压下非平衡放电等离子体产生的条件及其物理和化学性能,综合评述了放电技术的理烟气中有害气体SO2,NOx,CO2的机理和研究现状。 相似文献
830.
廖业桂 《城市环境与城市生态》2002,(2)
为确保 2 0 0 0 - 2 0 10年桂林漓江上游进入城区水质能保持国家II类水质标准进行纳污总量控制及其水质变化规律研究。采用系数法对 2 0 0 0 - 2 0 10年陆源排污总量进行科学预测 ,按河流功能区划要求 ,首次利用动态数学模型计算河流在不同流量、不同纳污总量条件下保持II类水质的最适纳污值 ,探讨了漓江水质变化规律。为环境管理打下基础 相似文献