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81.
硝化液回流比对水解-A/O工艺脱氮效果的影响 总被引:2,自引:0,他引:2
以低碳氮比城市污水为处理对象,在生产性试验规模上,研究不同硝化液回流比情况下水解-A/(缺氧-好氧)O工艺脱氮效果,并以相对小时去除量为评价量,讨论回流比对脱氮效果的影响.结果表明:水解-A/O工艺对COD,TN,NH4+-N,TP的平均去除率分别达到84.0%,64.2%,98.2%和73.2%,出水除TP和SS外,COD,TN以及NH4+-N都达到了GB18918—2002的一级A标准;在高硝化液回流比工况下,工艺运行效果更好;在硝化液回流比为200%的工况下,该工艺系统和水解池出水COD,NH4+-N,TN及TP比硝化液回流比为100%时分别低8.90,0.07,3.74,0.58mg/L和25.40,6.22,4.09,1.46mg/L.通过物料衡算,采用相对小时去除量的比值作为评价量,评价结果表明:在较高硝化液回流比条件下,水解池对污染物的去除能力增强,减轻了A/O生物池的去除负荷,进而增强了整个工艺对污染物的去除能力. 相似文献
82.
Linearity and linear range are the key evaluations of the accuracy in assay validation. The average deviation from linearity (ADL) and the sum of squares of deviations from linearity (SSDL) have been proposed for assessment of the linearity. However, both ADL and SSDL do no consider the variability of the assay for evaluation of linearity. Therefore, we proposed the coefficient of variation of deviations from linearity (CVDL) as an alternative measure for the linearity assessment. For the inference of evaluation of linearity, we proposed testing procedures based on generalized pivotal quantities (GPQ) of ADL and CVDL for evaluation of linearity. The simulation studies were conducted to empirically investigate the size and power between the three methods. The simulation results show that all three methods adequately control size. However, the ADL method is uniformly more powerful than the other two methods. A numeric example illustrates the proposed methods. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
83.
研究Lagrange系统的一类对称性,称为弱Noether对称性.给出弱Noether对称性的判据,证明由这种对称性也可以求得Noether守恒量.弱Noether对称性比Noether对称性有更广泛的应用. 相似文献
84.
In this paper we consider analytic vector fields X0 having a non-degenerate center point e. We estimate the maximum number of small amplitude limit cycles, i.e., limit cycles that arise after small perturbations of X0 from e. When the perturbation (Xλ) is fixed, this number is referred to as the cyclicity of Xλ at e for λ near 0. In this paper, we study the so-called absolute cyclicity; i.e., an upper bound for the cyclicity of any perturbation Xλ for which the set defined by the center conditions is a fixed linear variety. It is known that the zero-set of the Lyapunov quantities correspond to the center conditions (Caubergh and Dumortier (2004) [6]). If the ideal generated by the Lyapunov quantities is regular, then the absolute cyclicity is the dimension of this so-called Lyapunov ideal minus 1. Here we study the absolute cyclicity in case that the Lyapunov ideal is not regular. 相似文献
85.
The Euler equations with two controls are discretized by using the bilinear transformation method. The discrete equations are explicit and exhibit a sufficient number of conserved quantities for integrability. The explicit solution to the discrete controlled Euler top are deduced in terms of elliptic functions. 相似文献
86.
87.
LIU Yang-Kui FANG Jian-Hui PANG Ting LIN Peng 《理论物理通讯》2008,50(9):603-606
Two new types of conserved quantities deduced by Noether-Mei symmetry of nonholonomic mechanical system are studied. The definition and criterion of Noether-Mei symmetry for the system are given. A coordination function is introduced, and the conditions under which the Noether-Mei symmetry leads to the two types of conserved quantities and the forms of the two types of conserved quantities are obtained. An illustrative example is given. The coordination function can be selected according to the demand for finding the gauge function, and the choice of the coordination function has multiformity, so more conserved quantities deduced from Noether-Mei symmetry of mechanical system can be obtained. 相似文献
88.
从一维减幅-增幅谐振子的运动微分方程出发得到系统的运动积分常数,从而得到系统的Lagrange函数和Hamilton函数,再根据Hamilton函数的形式假定守恒量的形式,由Poisson括号的性质得到了系统的三个守恒量,并讨论与三个守恒量相应的无限小变换的Noether对称性与Lie对称性.还对守恒量与对称性的物理意义作了合理的解释.
关键词:
一维减幅-增幅谐振子
守恒量
Noether对称性
Lie对称性 相似文献
89.
90.