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101.
引入新变量,并利用高阶泰勒展开完成半导体平板微腔自发发射的空间积分,由此得到半导体平板微腔TE模式自发发射的近似表达式.在腔长为半个中心波长和高反射率腔面的半导体平板微腔中,结合电子和空穴的费米分布函数,用近似方法计算垂直方向小角度内自发发射谱和总的自发发射谱,分别与数值空间积分基本相同,可以用于计算量子阱平板微腔自发发射谱.  相似文献   
102.
Total glucosides of paeony are the active constituents of Paeoniae Radix Alba. In this study, a novel strategy was proposed to find more metabolites and the differences between paeoniflorin, albiflorin and total glucosides of paeony (TGP). This strategy was characterized as follows: firstly, the animals were divided into three groups (paeoniflorin, albiflorin and TGP) to identify the source of TGP metabolites from paeoniflorin or albiflorin; secondly, a generic information‐dependent acquisition scan for the low‐level metabolites was triggered by the multiple mass defect filter and dynamic background subtraction; thirdly, the metabolites were identified with a combination of data‐processing methods including mass defect filtering, neutral loss filtering and product ion filtering; finally, a comparative study was used in the metabolism of paeoniflorin, albiflorin and TGP. Based on the strategy, 18 metabolites of TGP, 10 metabolites of paeoniflorin and 13 metabolites of albiflorin were identified respectively. The results indicated that the hydrolysis, conjugation reaction and oxidization were the major metabolic pathways, and the metabolic sites were the glycosidic linkage, the ester bond and the benzene ring. This study is first to explore the metabolism of TGP, and these findings enhance our understanding of the metabolism and the interactions of paeoniflrin and albiflorin in TGP. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
103.
In this paper, we propose a parareal algorithm for stochastic differential equations (SDEs), which proceeds as a two-level temporal parallelizable integrator with the Milstein scheme as the coarse propagator and the exact solution as the fine propagator. The convergence order of the proposed algorithm is analyzed under some regular assumptions. Finally, numerical experiments are dedicated to illustrating the convergence and the convergence order with respect to the iteration number $k$, which show the efficiency of the proposed method.  相似文献   
104.
In this paper, we couple the parareal algorithm with projection methods of the trajectory on a specific manifold, defined by the preservation of some conserved quantities of stochastic differential equations. First, projection methods are introduced as the coarse and fine propagators. Second, we apply the projection methods for systems with conserved quantities in the correction step of original parareal algorithm. Finally, three numerical experiments are performed by different kinds of algorithms to show the property of convergence in iteration, and preservation in conserved quantities of model systems.  相似文献   
105.
NiSO_4/γ-Al_2O_3的酸性强烈影响其催化丙烯齐聚的活性。CO中毒实验和ESR表征证明,在反应过程中有Ni~+产生,并成为反应的活性中心。推测NiSO_4/γ-Al_2O_3上丙烯齐聚反应除通过酸中心上酸催化进行外,还通过Ni~+上配位催化进行。  相似文献   
106.
Summary Formylferrocenyl-3-hydroxyl-2-naphthoylhydrazone and its transition metal coordination compounds have been synthesized and characterized by elemental analyses, i.r., 1H-n.m.r., u.v.-vis., t.g.-d.t.a. and molar conductivities. The results show that the ligand coordinates to transition metal ions in the enolic form, accompanied by the release of acetate or nitrate.  相似文献   
107.
本文研究了在三种情况下直线上的区间图的最小独立控制集的计算问题:1.相交于一点的直线簇,2.除一条直线外,其余的直线都平行的直线簇,3.一条直线和直线上t个赋权的点,使得其最小独立控制集所覆盖的点的权和最大.本文给出了这三个问题的多项式时间算法,问题1可以在O(n)时间内求解,借助动态规划方法问题2和问题 3分别可以在O(n log n),O(n t)时间内求解.  相似文献   
108.
An experiment of laser propagation was carried out at the urban terrain range of 3.5 km during the period of March to May of 2006. The received intensity scintillations and atmosphere turbulence strength in complex urban atmosphere circumstance were simultaneously measured concentratively. The results show the statistical characteristics of irradiance scintillation and atmosphere turbulence strength and link fade margin for urban free-space optical links.  相似文献   
109.
The purpose of this study was to develop a novel, simple and precise ligand-exchange capillary electrophoresis method to separate the diastereomer pairs of four major cinchona alkaloids (quinine/quinidine and cinchonine/cinchonidine). The l-lysine and copper(II) were chosen as the ligand and the central ion, respectively. Optimal separation conditions of four alkaloids were 4.0 mM l-lys, 2.0 mM copper(II) and 30 mM NH4Ac at pH 8.9 and a applied voltage of 15 kV . Meanwhile, the first-order derivative electropherogram was used for resolving the overlapping peaks of cinchonidine and quinidine. Under the optimum condition, good linearities were obtained with correlation coefficients from 0.9908 to 0.9935. The limits of detection (LOD, S/N?=?3) and the limits of quantitation (LOQ, S/N?=?10) ranged from 0.24 to 0.41 μg/mL and from 0.73 to 1.35 μg/mL, respectively. The recoveries ranged between 95.38 and 106.03%. The proposed ligand-exchange capillary electrophoresis method was suitable for the quantitative determination of four cinchona alkaloids in some preparations such as Compound Quinine Injection, Tonic Water and Klorane quinine and Vitamin B complex Shampoo.  相似文献   
110.
13C 2D-PASS spectra of two new cis-dioxo catecholatomolybdenum complexes (NH2CH2NH2CHCH2)2(H+)3[MovO 2(C6H4O2)2] and (NH2CH2CH2CH2NH2)2(H+)3[Mo(v)O2 (C2H2O2)2] have been obtained by solid-state nuclear magnetic resonance (NMR), in which the spinning sidebands were well-separated. The principal components of the 13C shielding tensors were extracted by theoretically fitting the intensities of 13C spinning sidebands. The effects of counter cations on 13C chemical shift isotropy and shielding tensor of cis-dioxo catecholatomolybdenum complex anion [Mo (v)O2(C6H4O2)2]3− were studied, comparing the 13C CSA of those carbon sites in complex anions with that of the counter cations. Based on the known structure of the molybdenum complex crystal, theoretical values of 13C shielding tensors were calculated by the ainitio GIAO method, in comparison with the experimental results.  相似文献   
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