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131.
提供了一种简单而有效的利用计算机辅助进行塔板布置的方法。给出了相应的计算内容和程序。有较好的通用性。适用于浮阀塔板和筛孔塔板。 相似文献
132.
Huu D Doan Jiangning Wu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(9):1076-1083
Wastewater containing propylene glycol methyl ether from a powder and E‐coating plant was treated biologically. The wastewater was circulated through a packed column at rates of 0.014, 0.028, and 0.042 m3 m?2 s?1 (14, 28, and 42 kg m?2 s?1) with an airflow in a countercurrent direction. Various air flowrates from 0.034 to 0.10 m3 m?2 s?1 (0.041–0.12 kg m?2 s?1) were used. The removal of the biological oxygen demand (BOD) of the wastewater did not change significantly with the air flowrate. After 4 days of treatment in the packed column the BOD was reduced by about 70% while a BOD reduction of 10% was observed with the wastewater in a stagnant tank. BOD removal with aeration in the packed column was about 40% higher than that without aeration. At the air flowrate of 0.068 m3 m?2 s?1 and the liquid flowrate of 0.028 m3 m?2 s?1, BOD removal for the wastewater seeded with Polyseed® increased by about 25% compared with that of the unseeded wastewater. In order to minimize the power consumption, cyclic pumping of the liquid to the packed column with aeration was also tested. For the liquid‐pumping cycle of 2‐h on and 4‐h off, BOD removal was about the same as that with a continuously pumping operation. © 2002 Society of Chemical Industry 相似文献
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The aim of this study was the qualitative and quantitative assessment of impacts on the physicochemical characteristics of the water column and the sediment caused by an intensive marine fish farm. The study area was the Plateia Island which is located in an open seawater area in the outer part of Argolikos Gulf (Northeastern Peloponnese, Greece). The particular plant has been in operation since 1988, producing about 350-400 tons per year of Gilthead seabream (Sparus auratus) and European seabass (Dicentrarchus labrax). The samples were taken on a three-season period started in August 2001 and ended in May 2002. During this study, the main physical and geochemical parameters on the water column and the sediment were investigated. Specifically, the parameters that were measured included: ammonium-nitrogen, phosphate and suspended solids in the water column and organic matter, organic carbon, and phosphorus (total and inorganic) in the sediment samples. The conclusions drawn from this work clearly verify that the most important impacts, mainly identified as increased nutrients and organics concentrations both in the water column and the sediment, were realized at the stations closest to the farm. These concentrations gradually decreased with increasing distance from the cages. The peak values in most of the parameters measured were obtained during summer or spring. However, it has to be mentioned that although the measured concentrations clearly depict the influence of the fish farm especially on the sediment, their values were, in general, considerably lower than those reported in relative studies in Greek fish farms. 相似文献
135.
气相色谱法测定饲料香味剂中香味成分的含量 总被引:2,自引:0,他引:2
用气相色谱氢火焰离子化检测器,SE-52毛细管柱对四甲苯做内标,分别饲料香味剂中NB-68200香精液组分的含量,分离效果好。 相似文献
136.
垂直管内弹状气泡上升中壁面传递的实验研究 总被引:2,自引:0,他引:2
垂直管内弹状流壁面传递是诸多工业应用中需研究的重要问题之一。今用极限扩散电流技术,对弹状气泡上升时瞬时壁面剪应力和传质系数进行了测定,结果显示:当基于表观气速的Froude数FrG < 0.74时,壁面剪应力随弹状气泡和液塞的到来呈现方向相反的交替变化,壁面传质系数亦相应变化;而当FrG > 0.74时,剪应力方向一直向下,说明液膜向下流动,且弹状气泡和液塞的到来对壁面传质系数的影响很小。这说明下落液膜射流穿透了液塞段,控制了整个壁面传递过程。研究还对下落液膜区、尾迹区及液塞段的不同传递特征及机理进行了分析, 并结合气泡塔熔融结晶器中弹状气泡上升时的传热,对结晶操作条件的合理选择进行了讨论。 相似文献
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Electrochemical parameters of the nanoporous carbide-derived carbon|organic electrolyte have been studied by cyclic voltammetry and electrochemical impedance spectroscopy. The gas adsorption measurements have been used for evaluating the specific surface area, pore size distribution and porosity as the essential parameters influencing the double layer performance of carbon. The region of ideal polarizability, values of series and parallel resistance, capacitance and other important electrical double layer parameters were established. It was shown that specific capacitance of typical nanoporous carbon derived from titanium carbide is in the range of 70-90 F cm−3 or 100-130 F g−1 and it depends on the synthesis conditions. The influence of the electrolyte solvent to the capacitance was insignificant, although acetonitrile was advantageous with respect of smaller viscosity. 相似文献
140.