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61.
Milindkumar S. Kalekar 《Journal of Dispersion Science and Technology》2013,34(7):1027-1034
Adsorption of various surfactants at the gas liquid interface is studied with equilibrium and dynamic surface tension measurements. The Wilhelmey plate method and maximum bubble pressure method are used for this study. Dynamic surface tension of solutions of different surfactants, sodium lauryl sulfate (SLS), polyoxyethylene glycol 4‐tert‐octyl phenyl ether (Triton X 100), poly‐oxyethylene(20) cetyl ether (Brij 58), and tetraethylene glycol mono‐n‐dodecyl ether (Brij 30), is measured at different concentrations. Adsorption of different surfactants is compared on the basis of equilibrium and dynamic behavior. Effectiveness and efficiency of different surfactants is found from equilibrium surface tension measurement. A new parameter is defined to quantify the dynamic behavior of adsorption, which gives the concentration of surfactant needed to reduce surface tension to half of its maximum reduction within a defined time available for adsorption. The dynamics of surfactant solution is quantified by using this parameter. 相似文献
62.
Yan-nan LIU & Huai-yu JIAN Department of Mathematical Sciences Tsinghua University Beijing China 《中国科学A辑(英文版)》2007,50(2):231-239
In this paper, we study the evolution of hypersurface moving by the mean curvature minus an external force field. It is shown that the flow will blow up in a finite time if the mean curvature of the initial surface is larger than some constant depending on the boundness of derivatives of the external force field. For a linear force, we prove that the convexity of the hypersurface is preserved during the evolution and the flow has a unique smooth solution in any finite time and expands to infinity as the time tends to infinity if the initial curvature is smaller than the slope of the force. 相似文献
63.
广义多目标minmax问题的最优性条件和极大熵方法 总被引:1,自引:0,他引:1
本文讨论了广义多目标minmax问题的最优性条件。利用极大熵逼近函数,研究了广义多目标minmax;问题的逼近问题,在较弱的条件下,证明了由极大熵逼近函数导出的多目标逼近问题的临界点的任一极限点均为原广义多目标minmax问题的临界点。 相似文献
64.
We present a density matrix of a mesoscopic RLC circuits to make it possible to analyze the connection between the initial
condition and the certain temperature. Our results show that the quantum state evolution will be closely related to the initial
condition; the system evolves to generalized coherent state if it is in ground state initially, and evolves to squeezed state
if it is in excited state initially. In addition, we also obtain squeezed minimum uncertainty state with satisfying certain
condition in mesoscopic RLC circuit. 相似文献
65.
The linear 2-arboricity la_2(G) of a graph G is the least integer k such that G can be partitioned into k edge-disjoint forests,whose component trees are paths of length at most 2.In this paper,we prove that if G is a 1-planar graph with maximum degree Δ,then la_2(G)≤[(Δ+1)/2]+7.This improves a known result of Liu et al.(2019) that every 1-planar graph G has la_2(G)≤[(Δ+1)/2]+14.We also observe that there exists a 7-regular 1-planar graph G such that la_2(G)=6=[(Δ+1)/2]+2,which implies that our solution is within 6 from optimal. 相似文献
66.
Jih-Hsin Cheng 《数学研究》2020,53(4):471-492
In this paper I would like to make a report on the results about hypersurfaces in the Heisenberg group and invariant curves and surfaces in CR geometry. The
results are contained in the papers [8, 9, 16] and [14]. Besides, I would also report
on the results about the strong maximum principle for a class of mean curvature type
operators in [10]. 相似文献
67.
68.
图像分割是图像分析、识别和理解的基础。图像分割主要是指将图像分成各具特性的区域并提取出感兴趣目标的技术,其研究多年来一直受到人们的高度重视;阈值化法是图像分割的一种重要方法,在图像处理与识别中广为应用;针对图像分割中细节往往被忽略导致后续处理困难的问题,基于模糊关系和最大模糊熵原理提出了一种阈值化方法,对二维直方图进行模糊分割;为了获得图像分割中的细节,提出的方法根据最大熵原则自动确定模糊区域和门限,进而获得二维模糊熵和遗传算法最优解,最后获得图像细节;通过对不同灰度水平和颜色类型图像进行实验比较,实验结果表明提出的方法优于二维非模糊方法和一维模糊熵分割法,得到该方法在图像分割中获得细节的结论。 相似文献
69.
70.