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31.
The application of electrochemical sensors for measurement of concentration of pollutant gases in air in the part-per-billion (109) range is reviewed. Performance-limiting factors, particularly the effects of extremes and of relatively rapid changes in ambient temperature and humidity, are noted. Variations in composition of the electrolyte in the meniscus at the electrode–gas interface and instability of the solid–liquid–gas contact line, causing important variations in current due to background electrode reactions, are deduced and suggested as the reason for the performance limitations. Suggestions are made for mitigation through instrument design. 相似文献
32.
The adsorption of particles to air–aqueous interfaces is vital in many applications, such as mineral flotation and the stabilization of food foams. The forces in the system determine whether a particle will attach to an air–aqueous interface. The forces between a particle and an air–aqueous interface are influenced by Derjaguin–Landau–Verwey–Overbeek forces (i.e. van der Waals and electrostatic forces), non–Derjaguin–Landau–Verwey–Overbeek forces (e.g. hydrophobic, hydrodynamic, structural, and capillary forces), liquid drainage, and liquid flow. As an air–aqueous interface can be deformed by a particle, the forces measured between an air–aqueous interface and a particle can differ from those measured between two hard surfaces separated by liquid. The presence of a film at an air–aqueous interface can also change the forces. 相似文献
33.
我们用三角和的性质研究一类三次Gauss和与两项指数和混合均值的计算问题,并给出一个精确的计算公式. 相似文献
34.
The Bayesian model are established for the VaR and related risk measurements. The relationship between VaR and other risk measurements including expect shortfall, tail condition expectation and conditional value at risk are discussed. Furthermore, the Bayesian estimates and Bayesian predictors of these risk measurement are derived. Thirdly, the consistency and asymptotic normality in the exponential risk model are proved. Finally, the numerical simulation method is used to verify the convergence rate under different sample sizes. 相似文献
35.
为解决脉冲电场测试系统中的供电问题,设计了一套激光光纤供电系统,该系统由激光器、多模光纤及光电池构成。重点研究了激光器与光纤的耦合问题,设计了透镜系统对激光器输出光束进行准直和压缩。通过MOCVD法研制了GaAs光电池,并制作了椭球形"光伏眼"来提高光电转换效率。仿真和实验表明:采用透镜耦合时,激光器与光纤的耦合效率可达80%以上,远远高于直接耦合时的16%,改进后的"光伏眼"耦合效率相比直接耦合时提高了54.5%,激光供电系统的转化效率在40%以上。该系统的研制为解决脉冲电场的供电问题提供了一种方案。 相似文献
36.
In this paper, for a finite group, we investigate to what extent its directed (resp. undirected) reduced power graph determines its directed power graph (resp. reduced power graph). Moreover, we investigate the determination of the orders of the elements of a finite group from its directed (resp. undirected) reduced power graph. Consequently, we show that some classes of finite groups are recognizable from their undirected reduced power graphs. Also, we study the relationship between the isomorphism classes of groups corresponding to the equivalence relations induced by the isomorphism of each of these graphs on the set of all finite groups. 相似文献
37.
Hüseyin Bor 《Numerical Functional Analysis & Optimization》2019,40(4):484-489
In this article, we prove a general theorem dealing with an application of quasi-f-power increasing sequences and δ-quasi monotone sequences. This theorem also includes some known and new results. 相似文献
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