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991.
This work was focused on the influence of match degree of structure parameters i.e. molecular size, volume and polarity (denoted as Rd, Vd and Pd) between imprinted cavities in Qu-MIP and Xn on the adsorption selectivity. The results presented that the influence of Rd on the adsorption selectivity was the largest and the most regular, while the influence of Pd was the smallest and the most irregular. Besides, the influence degree of Vd was decreased in general with the increase of Rd. However, as Rd was in the threshold of [0.99, 1.02], Vd would rise to the major influence factor. Furthermore, utilizing data obtained from experiment, the influence authority of Rd, Vd and Pd on the adsorption selectivity was calculated theoretically through multiple linear regression and principal component analysis of IBM SPSS Statistics 20, and results showed the authority order was Rd, Vd and Pd at any circumstance despite the value was different, which was in accordance with the result we directly inducted from the experiment. 相似文献
992.
Haifeng Pan Weidong Pan Shengnan Zhao Yilong Du Yanrong Li Mingyu Yang 《液相色谱法及相关技术杂志》2017,40(7):361-368
The aim of this study was to raise the quality control level of Scutellaria indica. A quick and stable ultra performance liquid chromatography method was established for the fingerprint analysis of S. indica. A total of 32 common peaks were marked with 10 batches S. indica detected in 30?min using similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004A version). Besides, a high-resolution mass spectrometer was used to identify flavonoids in S. indica. A total of 27 flavonoids in S. indica were identified. And a series of fragmentation regularities were obtained, which could be used for the identification of other flavonoids. Therefore, the established liquid chromatography–tandem mass spectrometer method could be successfully utilized for the quality control of S. indica. 相似文献
993.
Xuan Shen Xiaohong Xia Weichun Ye Yongling Du Chunming Wang 《Journal of Solid State Electrochemistry》2017,21(2):409-417
Hexagram-like CoS-MoS2 composites were prepared on indium tin oxide (ITO) conductive glasses via cyclic voltammetry electrodeposition using Co(NO3)2 and (NH4)2MoS2 as precursors and tested for application in hydrogen evolution reaction (HER). The structure of CoS-MoS2 composites was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and X-ray photoelectron spectrum (XPS). Electrochemical characterizations indicate that CoS-MoS2 composites exhibit more excellent catalytic activity and stability than MoS2. Compared with pure MoS2, the hexagram-like CoS-MoS2 composites with increased specific surface area improved the density of exposed active sites, and the Co binding S edges in CoS-MoS2 composites promote the number of highly catalytic edge sites and decreased the binding energy △G H. Moreover, the effects of different substrates on the CoS-MoS2 composites were also investigated. Our further understanding of this highly active hydrogen evolution catalyst can facilitate the development of economical electrochemical hydrogen production systems. 相似文献
994.
995.
In this paper, the nonlinear iterative methods, which are different from the classical algorithms, to solve inverse problems are presented. Our methods by denoting some parameters and some properties of the algorithm in both noise and noiseless cases are studied. Finally, the convergence of the sequence generated by the algorithm without noise is discussed. 相似文献
996.
Home owners are typically charged differently when they consume power at different periods within a day. Specifically, they are charged more during peak periods. Thus, in this paper, we explore how scheduling algorithms can be designed to minimize the peak energy consumption of a group of homes served by the same substation. We assume that a set of demand/response switches are deployed at a group of homes to control the activities of different appliances such as air conditioners or electric water heaters in these homes. Given a set of appliances, each appliance is associated with its instantaneous power consumption and duration, our objective is to decide when to activate different appliances in order to reduce the peak power consumption. This scheduling problem is shown to be NP-Hard. To tackle this problem, we propose a set of appliance scheduling algorithms under both offline and online settings. For the offline setting, we propose a constant ratio approximation algorithm (with approximation ratio \(\frac{1+\sqrt{5}}{2}+1\)). For the online setting, we adopt a greedy algorithm whose competitive ratio is also bounded. We conduct extensive simulations using real-life appliance energy consumption data trace to evaluate the performance of our algorithms. Extensive evaluations show that our schedulers significantly reduce the peak demand when compared with several existing heuristics. 相似文献
997.
Nikolaos S. Papageorgiou Vicenţiu D. Rădulescu Dušan D. Repovš 《Journal of Optimization Theory and Applications》2017,175(2):293-323
We consider a nonlinear, nonhomogeneous Robin problem with an indefinite potential and a nonsmooth primitive in the reaction term. In fact, the right-hand side of the problem (reaction term) is the Clarke subdifferential of a locally Lipschitz integrand. We assume that asymptotically this term is resonant with respect the principal eigenvalue (from the left). We prove the existence of three nontrivial smooth solutions, two of constant sign and the third nodal. We also show the existence of extremal constant sign solutions. The tools come from nonsmooth critical point theory and from global optimization (direct method). 相似文献
998.
The asymptotic field near an interface crack tip is analyzed with the fully nonlinear theory. By dividing the crack tip field
into narrowing sectors and an expanding sector, the asymptotic equations for the crack tip field are derived and solved. The
singular characters of stress and strain near the crack tip are revealed. 相似文献
999.
1000.
板带轧制过程中的三维接触摩擦模型 总被引:3,自引:0,他引:3
为解决压力加工中工具与工件间的接触摩擦问题,根据金属流动对摩擦的反作用,在轧辊和工件之间引入了一层极薄的摩擦单元并将其编入三维弹塑性大变形有限元程序。通过调节摩擦元尺寸厚度和β因子,实现了对薄板轧制过程中间介质的几何尺寸模拟和物理特征模拟。该法不用对摩擦力大小、方向及中性点位置进行假定,通过计算能够得到全部有关信息。 相似文献