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201.
The adsorption behaviour of Diphenylamine (DPAM), napthylamine ( NAM), napthylamine ( NAM)and aniline on pyrolusite and activated carbon has been studied.Pyrolusite shows remarkable sorption capacity for DPAM and NAM as compared to aniline; (the adsorption followed theorder:Activated Carbon: DPAM = NAM > AnilinePyrolusite: DPAM: NAM > NAM> Aniline)The maximum adsorption of NAM occurred in theconcentration range 4–20 g mL-1 on pyrolusite (95%)and 4–50 g mL-1 on activated carbon (100%). Theeffect of various doses of activated carbon on the adsorption of NAM confirm Langmuir and Freundlich isotherms where asFreundlich isotherm is obeyed by pyrolusite. The adsorption of NAM on both the absorbents is not affected in presence ofDPAM over a wide range of their initial concentrations (20–60g mL-1). The desorption studies of NAM onpyrolusite was carried out by batch as well as column processes.Excellent results were obtained when a mixture of n-hexane andisopropanol (91:1) was used as eluent.  相似文献   
202.
A field monitoring network was set up within the Stamford canal watershed in 1989 to study both the quantitative and qualitative aspects of storm runoff from this urbanised catchment. The data acquisition equipment comprised a continuous recording rain gauge, a water level recorder and an automatic water sampler capable of sampling storm runoff at preset intervals during rainfall events. Water samples were collected after each storm and laboratory tests were carried out on the physical and chemical properties of the storm water. Preliminary findings on the temporal variations of stormwater quality during single storms and the effects of antecedent dry weather period on the quality are presented. The average ranges of some of the significant quality parameters found in the storm runoff were also established. The quality of storm runoff from the catchment under study was found to be of an acceptable level and could potentially be developed as a water catchment area.  相似文献   
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This paper describes a method for predicting local scour around bridge piers using an artificial neural network (ANN). Methods for selecting input variables, calibrations of network control parameters, learning process, and verifications are also discussed. The ANN model trained by laboratory data is applied to both laboratory and field measurements. The results illustrate that the ANN model can be used to predict local scour in the laboratories and in the field better than other empirical relationships that are currently in use. A parameter study is also carried out to investigate the importance of each input variable as reflected in data.  相似文献   
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The dysgnathia complex (agnathia-otocephaly) (AO) is a lethal malformation that consists of congenital absence of the lower jaw with union or close approximation of the lower ears on the front of the neck, microstomia, and hypoglossia. We present a novel case of agnathia-otocephaly with associated organomegaly and the use of postmortem 3-D computed tomographic rendering. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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