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911.
912.
NANOBUBBLES AT THE LIQUID/SOLID INTERFACE STUDIED BY ATOMIC FORCE MICROSCOPY 总被引:2,自引:0,他引:2
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Bubbles on the nanometer scale were produced by a special method on solid surfaces. Atomic Force Microscopy (AFM) was used to detect these bubbles. It shows that nanobubbles can be seen clearly in the interfaces of liquid/graphite and liquid/mica. In AFM images, the nanobubbles appeared like bright spheres. Some of the bubbles kept stable for hours during the experiments. The bubbles were disturbed under high load during AFM imaging. The conformation of the bubbles is influenced by the atomic steps on the graphite substrate. In addition, a shadow was found around the bubbles, which was due to the interactions between a bubble adhered to the tip and a bubble on the substrate. 相似文献
913.
Feng Huang Qihong Lou Tianyan Yu Jingxing Dong Bo Lei Yunrong Wei 《Optics & Laser Technology》2001,33(2):111
A tunable Ti:sapphire laser pumped by an intracavity frequency-doubled YAG laser was designed, and third-harmonic generation of the tunable Ti:sapphire laser was achieved by rotating the cardinal plane of the crystal through a multi-crystal cascade method. The parameters such as crystal length, time predelay, and intensity ratio related to the efficiency of third-harmonic generation are analyzed by nonlinear equations. 相似文献
914.
915.
Robert Stephen Cantrell Chris Cosner Yuan Lou 《Journal of Differential Equations》2008,245(12):3687-3703
We consider reaction-diffusion-advection models for spatially distributed populations that have a tendency to disperse up the gradient of fitness, where fitness is defined as a logistic local population growth rate. We show that in temporally constant but spatially varying environments such populations have equilibrium distributions that can approximate those that would be predicted by a version of the ideal free distribution incorporating population dynamics. The modeling approach shows that a dispersal mechanism based on local information about the environment and population density can approximate the ideal free distribution. The analysis suggests that such a dispersal mechanism may sometimes be advantageous because it allows populations to approximately track resource availability. The models are quasilinear parabolic equations with nonlinear boundary conditions. 相似文献
916.
917.
了解疏水表面的滑移规律对其在流动减阻方面的应用至关重要.利用耗散粒子动力学(dissipative particle dynamics, DPD)方法研究了微通道疏水表面的滑移现象.采用固定住的粒子并配合修正的向前反弹机制,构建了DPD固体壁面边界模型,利用该边界模型模拟了平板间的Couette流动.研究结果表明,通过调整壁面与流体间排斥作用强度,壁面能实现从无滑移到滑移的转变,壁面与流体间排斥作用越强,即疏水性越强,壁面滑移越明显,并且滑移长度与接触角之间存在近似的二次函数关系.无滑移时壁面附近密度分布均匀,有滑移时壁面附近存在低密度区域,低密度区域阻碍了动量传递,致使壁面产生滑移. 相似文献
918.
Lin He Zhu Qing Huang Chuan Yang Dong-Dong Lou Nan Zhu Shun-Guan Li Hong-Zhen 《Structural chemistry》2019,30(6):2401-2408
Structural Chemistry - The development of high energy density materials (HEDMs) with balanced detonation energy and sensitivity is an urgent task in the current energetic material field. Here, by... 相似文献
919.
本文提出全局优化的一类新的水平值估计方法,研究了方差方程的根与原始问题的最优值之间的等价性,并通过v-方差函数的研究,得出了相应的最优性条件. 相似文献
920.
Li-Li Lou Peng Zhao Zhuo-Yang Cheng Rui Guo Guo-Dong Yao Xiao-Bo Wang 《Natural product research》2019,33(12):1791-1793
In this study, a new coumarin, juglansoside C (1) was isolated from the bark of Juglans mandshurica. Its chemical structure was identified by comprehensive spectroscopic analyses. The in vitro cytotoxicity assay showed that 1 exhibited moderate cytotoxicity against human hepatocellular carcinoma Hep3B cells with an IC50 value of 70.9 μM. Furthermore, Annexin V-FITC/PI staining assay indicated that 1 markedly induced apoptosis in Hep3B cells. 相似文献