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51.
Reaction rate of alkaline supernatant of waste activated sludge (WAS) as carbon sources for denitrification was investigated to determine the recycling dosage preliminarily. WAS was digested under alkaline conditions and batch tests were carried out under different VFA/N ratio at SRT=9d to examine the denitrification rate and choose the optimal ratio. And then a comparative test was carried out for actual sewage wastewater and pure sewage wastewater to investigate its feasibility in recycle and the recycling dosage. It was found that denitrification curve of all ratios could be divided into four stages and the denitrification rate increased obviously with the increase of VFA/N ratio, which was consistent with that of the pH curve. While as the ratio increased beyond 2.47, the denitrification rate increased slowly. Furthermore, when the supernatant was added to the sewage wastewater to some extent, denitrification rate increased significantly and the removal amount of nitrate in two parallel tests were 47.0 and 33.9 mg/L, respectively. 相似文献
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A coking plant extended many times, and its capacity of the cooling water system is not match with it, the consumption of new water is much more than that used by others in the same industry. The water system renovation is addressed for an extended coking plant. The installation of two 600 m3/h cooling towers and restoration the existing two cooling towers are to promote the cooling capacity so that the amount of discharge and feed could be reduced. At the same time, the pipe net for waste water reutilisation is installed, by which part of the waste water is reused as supplement water for quenching hot coke and the other was piped to ironworks for reuse. With the field test, the water consumption per ton of coke production is cut down from 9.03 m3 to 3.21 m3. And the annual water saving is more than 6×106 m3. Furthermore, the electric consumption is reduced by 2×106 kWh and about 3×106 yuan of annual running cost is saved. 相似文献
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为了了解喷头内部流场的变化情况,根据计算流体力学的基本理论,运用Fluent软件对卷盘式喷灌机喷头内部流场进行了仿真。对在相同压力下不同规格型号的喷头以及相同规格型号的喷头在不同工作压力下的内部流场进行了分析,通过该仿真分析可直观了解在不同条件下,喷头内部流场的分布情况和变化趋势。因此对喷头内部流场的仿真分析在喷头设计或选型中都起着积极作用。 相似文献
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MYB转录因子家族基因具有保守的DNA结合域,是植物最大的转录因子家族之一,广泛参与植物的代谢调控,在植物生长发育和胁迫响应等方面发挥重要作用。为改良品种性状和提高生产实践能力,本研究采用RT-PCR法克隆蒺藜苜蓿MYB转录因子基因MtMYB,其编码区长255 bp,编码84个氨基酸。生物信息学分析表明,该基因编码蛋白与其他物种MYB蛋白具有很高的同源性,其中与红三叶同源性最高。荧光定量结果表明,MtMYB基因在蒺藜苜蓿叶片中的表达量最高。MtMYB基因在外源IAA、6-BA的诱导下,总体都呈现先上升后下降的趋势。同时本研究成功构建35S::MtMYB的植物表达载体,并通过转基因技术将其转化至拟南芥中,PCR检测表明,MtMYB已成功整合至转基因拟南芥基因组中。RT-PCR检测表明,MtMYB能够在转基因拟南芥中正常转录。本研究为进一步探明MtMYB基因的功能提供了数据参考和实验材料。 相似文献
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The high grade gray water was pre treated by biologic contact oxidation on load of 0.72 KgBOD5·m-3·d-1, and then post treated by constructed wetland. On the basis of experiment, it was found that: Totle nitrogen (TN) was the restrictive index of the combinational technique. To meet the reclaimed water quality standard and reuse for waterscape, the peak hydraulic load of constructed wetland was 0.50 m·d-1 in summer (30~36 ℃), and 0.33 m·d-1 in winter (8~12 ℃). And the load ratio of the peak hydraulic under the summer and winter conditions was 3:2. With the experimental results and reclaimed water quantity requirements in different seasons of buildings, treatment scale can be determined. 相似文献
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