【摘 要】
：
Pollution of toxic heavy metals and organic chemicals are most common environmental problem nowadays,for example,the bivalent cadmium(Cd(Ⅱ))and the parachloronitrobenzene.Hence the environment polluti
【机 构】
：
Key Laboratoryof Industrial Biocatalysis of Ministry of Education(Tsinghua University),Department of
论文部分内容阅读
Pollution of toxic heavy metals and organic chemicals are most common environmental problem nowadays,for example,the bivalent cadmium(Cd(Ⅱ))and the parachloronitrobenzene.Hence the environment pollution caused by these two pollutants was a common problem all over the world and their removal was highlighted by many researchers.Zero velent Fe nanoparticles(ZVFeNPs)are one kind of potential reducer to eliminate the toxic pollutants,but the application was plagued by the aggregation-prone problem similar to other nanoparticles.
其他文献
为了研究叶轮出口宽度对离心泵内部压力脉动的影响,在保证其它几何参数不变的前提下设计了5种不同叶轮出口宽度的叶轮,应用CFX软件对离心泵的设计点工况进行定常和非定常计算,得到离心泵内各监测点的压力脉动时域图和频域图.结果表明:数值模拟结果与外特性试验结果相吻合,证实了数值模拟的可行性.随着叶轮出口宽度的递减,轴频峰值变化明显,呈递增趋势,这表明叶轮出口宽度过窄容易导致流道堵塞,阻碍流态的发展.同时,
通常在发动机进气端加装进气防砂装置以保障发动机性能并提高寿命,涡旋管分离器在某种发动机进气防砂装置中是很重要的部件.本文采用离散相模型(Discrete Phase Model,DPM)计算分析了涡旋管分离器内的两相流动状态,并对其工作性能进行了评估.粒子流经涡旋管叶片时受到离心力,从而实现分离,大部分粒子经外侧出口流出,较干净空气经中间出口流入主流通道.给出了涡旋管的基本性能及粒子在涡旋管中的运
水泵水轮机压力脉动特性是影响机组稳定性的关键之一,其影响因素众多,流量、水头、转速、流道形状等的改变都会压力脉动特征发生变化.转轮出口边的形状改变也会使流道形状发生改变,因此本文以某一抽水蓄能电站为例,采用SIMPLE算法以及k-ε湍流模型分别对直线形和凹形两种出口边形状的转轮在水泵水轮机泵工况进行分析,,研究其内部压力脉动特性并使用快速傅里叶变换(FFT)对压力脉动做频域分析,进行结果对比分析.
出水量是光伏水泵系统的重要衡量指标,因而光伏水泵出水量预测模型一直是研究的热点.本文分别基于试验测试和相似理论建立了2种光伏水泵系统出水量预测模型,并用4种典型日照辐射对2个出水量预测模型的预测精度进行了验证.结果表明:在4种典型日照辐射情况下,两个预测模型的相对偏差均处于4％以内,2种出水量预测模型均能够很好的预测日照强度瞬态变化情况下的系统出水量.在日照辐射剧烈波动和缓慢变化时均能准确进行出水
为研究基于水轮机模型的微型水力回收装置在两相流工况条件下的工作特性,本文采用SST k-ω湍流模型和欧拉-欧拉两相流模型,对模型进行全流道数值模拟,分析在给定工况点时不同进口气体体积分数(GVF)下的两相流的流动特性.数值模拟结果表明透平的功率和效率随着气体体积分数的增大而减小.由于工质流体中气体的膨胀,流体的速度随着气体的增加而增加,导致叶轮出口附近的最大负压值区域面积变大.由于气体分子质量小,
Genome editing can introduce predetermined sequence changes to the target genome.In this work,a new genome editing method of tandem repeat assisted genome editing(TRAGE)was developed.This method can r
In contrast to the classical notion that enzymes always carry out highly specific reaction towards particular substrate,recent studies highlight both the widespread and underestimated biological funct
Enzymatic conversion of CO2 to fuel or chemicals is appealing,but is limited by lack of efficient technology for regeneration and reuse of expensive cofactors.Here we show for the first time that cati
The vapor-phase reactions of nascent volatiles derived from the fast pyrolysis of lignin were investigated both experimentally and numerically.Lignin obtained as a residue after enzymatic hydrolysis o
Banana pseudo-stem was liquefied in the mixture of polyhydric alcohols of polyethylene glycol(PEG400)and glycerol at the temperature of 130 ℃ to 170 ℃ with sulfuric acid as a catalyst.Hydroxyl value o