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791.
J. R. Philip 《Journal of contaminant hydrology》1998,33(3-4)
The one previous analytical solution to the steady sparging problem in a homogeneous soil was in the boundary-layer approximation that neglects the vertical capillary pressure gradient. The present study gives an analytical solution to the full air-flow equation, with the corresponding boundary-layer solution for comparison. The full solution predicts sparging below the air-injection point, whereas the boundary-layer solution does not. Solutions are expressed both in terms of the dimensionless Kirchhoff potential θ (increasing monotonically with capillary pressure and air saturation also) and the dimensionless Stokes stream function F (mapping the pattern of air flow). Both θ and F show the full solution predicting more effective sparging near the injection point than does the boundary-layer solution. The overall boundary-layer relative error, however, decreases as dimensionless air-injection depth below the undisturbed water-table increases. 相似文献
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We documented the spawning patterns of the leopard grouper, Mycteroperca rosacea, from April to June 2005 in the central Gulf of California, Mexico to draw comparisons with other aggregate-spawning groupers
and provide information useful for management of their fishery. Adults formed spawning aggregations of 150 to >700 individuals
at specific sites, and spawning occurred daily at these sites from late April through early June. Courtship occurred throughout
the day, but spawning was restricted to the evening hours. Adults spawned in groups of 6–40 fish, and pair-spawning was not
observed. The group-spawning behavior of adults and the gonosomatic indices of mature males (maximum = 7.2%) suggest that
sperm competition was present. The site-specificity of leopard grouper spawning aggregations and diel spawning period were
typical of most aggregating groupers, and the size and structure of these aggregations was similar to other species in the
genus Mycteroperca. Leopard grouper behavior patterns were unusual in that spawning aggregations persisted for extended periods, spawning was
not synchronized with the lunar cycle, and adults aggregated during non-spawning periods. The extensive duration and site-specificity
of spawning aggregations and the propensity of M. rosacea to form aggregations year-round increases the vulnerability of the species to overfishing. Policies that limit harvest from
these aggregations are needed to improve the management of leopard grouper fisheries in the Gulf of California. 相似文献
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Philip DeKoninck Julio Jimenez Francesca M. Russo Ryan Hodges Eduard Gratacós Jan Deprest 《黑龙江环境通报》2014,34(10):977-981
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Philip L Wylie 《环境化学》2008,27(4)
以美国环保局(USEPA)8260B方法为基础,分析水中挥发性有机化合物(VOC),虽然8260B方法的适用范围存在一定的局限性,但采用吹扫捕集(P&T)/气质(GC/MS)联用方法分析VOC时,该方法适用于大部分VOC的分析.使用新的"电子方法输入"(eMethod Import)这一化学工作站的特殊功能,能够加载方法和所有的参数,虽然吹扫捕集的参数不能自动输入,便在该电子方法中已包括了吹扫捕集的方法. 相似文献