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1.
Steady convective mass transfer to or from fluid interfaces in pores of angular cross-section is theoretically investigated.
This situation is relevant to a variety of mass transport process in porous media, including the fate of residual non-aqueous
phase liquid ganglia and gas bubbles. The model incorporates the essential physics of capillarity and solute mass transfer
by convection and diffusion in corner fluid filaments. The geometry of the corner filaments, characterized by the fluid–fluid
contact angle, the corner half-angle and the interface meniscus curvature, is accounted for. Boundary conditions of zero surface
shear (‘perfect-slip’) and infinite surface shear (‘no-slip’) at the fluid–fluid interface are considered. The governing equations
for laminar flow within the corner filament and convective diffusion to or from the fluid–fluid interface are solved using
finite-element methods. Flow computations are verified by comparing the dimensionless resistance factor and hydraulic conductance
of corner filaments against recent numerical solutions by Patzek and Kristensen (J. Colloid Interface Sci 236, 305–317 2001). Novel results are obtained for the average effluent concentration as a function of flow geometry and pore-scale
Peclet number. These results are correlated to a characteristic corner length and local pore-scale Peclet number using empirical
equations appropriate for implementation in pore network models. Finally, a previously published “2D-slit” approximation to
the problem at hand is checked and found to be in considerable error. 相似文献
2.
Wang Weishu Yuan Man Li Yun-Ze Li Chuang Ning Xian-Wen Li Tong 《Journal of Thermal Analysis and Calorimetry》2021,143(1):559-571
Journal of Thermal Analysis and Calorimetry - Sublimator offers effective heat rejection for the spacecraft, which work in warm environments or with peak heat loads, by evaporating or sublimating... 相似文献
3.
本文描述用硬X射线针孔成象法测量简单磁镜装置中ECR等离子体辐射特性的方法及其结果。这种非破坏性的成象法,直接显示了热电子等离子体的空间分布,一次放电可成一帧清晰的象,且由此可得出二维的等发射强度线。大量结果表明电子环是非轴对称的,并非为一个整环,而是在微波注入口的对面有一个缺口。当微波功率改变时,环也在改变。 相似文献
4.
回旋管磁场电流调节器的改进 总被引:1,自引:1,他引:0
一、引言 最近,用电子回旋共振加热(ECRH)产生热电子等离子体引起了人们很大兴趣。为开展ECRH在聚变装置的应用研究,我们在一个简单磁镜MM-2中,用频率15千兆赫回旋管建立热电子等离子体,并开展了一系列热电子环物理实验研究。在该装置实验中,我们发现,回旋管正常工作的关键是它的主磁场电源的稳定度。它要求电源输出500A时,电流稳定度优于0.05%。最早该电源用28只三极管并联作为电流调节器,由于管子参数分散性大,均流和 相似文献
5.
磁阱等离子体源离子注入研究 总被引:1,自引:0,他引:1
本文描述在磁阱装置中利用旋转等离子体的概念给浸泡于等离子体中的样品施加直流高压的实验工作,工件电压高达-22kV,文中还对相关物理问题进行了定性分析。 相似文献
6.
该文给出了一种用于多处理机系统中实现并行计算的最优映射问题的遗传算法,它对于在固定结构的并行系统中充分利用计算资源,提高计算效率具有实用价值,实践表明,采用遗传算法是解决任务最优映射问题的有效的方法. 相似文献
7.
Weishu Zhao Guillemette Picard Gabriela Leu Philip M. Singer 《Transport in Porous Media》2010,81(2):305-315
We report here the quantitative comparisons between the measured NMR flow propagator of a carbonate rock and the flow propagator
calculated with a porous network extracted from the micro-CT image of the twin plug. We developed a numerical model based
on a particle tracking algorithm in pore space. The particle tracking in throats is described using the first arrival time
distribution. As pores have an important volume fraction in the sample considered, we implemented a time-delay mechanism for
particle transport in the pores. We consider that the nodes have volume and there is a transport of the tracking particles
inside the nodes, which leads to an “apparent” time-delay. Simulations of flow propagator show good agreement with low field
NMR experiments performed on the twin plug of the sample used for pore network extraction with a single adjustable parameter
(that describes the dynamics in the pores). These results lead us to a better understanding of the connection between pore
structure and the behavior of NMR flow propagator in fluid-saturated rocks and are essential in interpreting the experimental
data and correlating NMR parameters to petrophysical properties. 相似文献
8.
Ruo-Chen Guo Ning Wang Weishu Wang Zeyu Zhang Wendi Luo Yushi Wang Haiqin Du Prof. Yifei Xu Prof. Gongyu Li Prof. Zhilin Yu 《Angewandte Chemie (International ed. in English)》2023,62(49):e202314578
The presence of disordered region or large interacting surface within proteins significantly challenges the development of targeted drugs, commonly known as the “undruggable” issue. Here, we report a heterogeneous peptide-protein assembling strategy to selectively phosphorylate proteins, thereby activating the necroptotic signaling pathway and promoting cell necroptosis. Inspired by the structures of natural necrosomes formed by receptor interacting protein kinases (RIPK) 1 and 3, the kinase-biomimetic peptides are rationally designed by incorporating natural or D-amino acids, or connecting D-amino acids in a retro-inverso (DRI) manner, leading to one RIPK3-biomimetic peptide PR3 and three RIPK1-biomimetic peptides. Individual peptides undergo self-assembly into nanofibrils, whereas mixing RIPK1-biomimetic peptides with PR3 accelerates and enhances assembly of PR3 . In particular, RIPK1-biomimetic peptide DRI-PR1 exhibits reliable binding affinity with protein RIPK3, resulting in specific cytotoxicity to colon cancer cells that overexpress RIPK3. Mechanistic studies reveal the increased phosphorylation of RIPK3 induced by RIPK1-biomimetic peptides, elucidating the activation of the necroptotic signaling pathway responsible for cell death without an obvious increase in secretion of inflammatory cytokines. Our findings highlight the potential of peptide-protein hybrid aggregation as a promising approach to address the “undruggable” issue and provide alternative strategies for overcoming cancer resistance in the future. 相似文献
9.
用碘化钠探测器研究简单磁镜装置MM—2中热电子环特性 总被引:1,自引:1,他引:0
使用碘化钠(NaI)探测器,对MM-2简单磁镜装置中热电子环参数进行了测量,得到热电子温度为140—170keV,热电子环的半径为7cm,其径向厚度为4cm,轴向尺寸边缘区域从±10cm延伸至±20cm,同时也观测到了热电子密度沿径向分布,环的位置与磁场强度的关系以及硬X射线发射的时间特性。 相似文献
10.
Zhang Q Cao F Liu W Lukas K Yu B Chen S Opeil C Broido D Chen G Ren Z 《Journal of the American Chemical Society》2012,134(24):10031-10038
We present detailed studies of potassium doping in PbTe(1-y)Se(y) (y = 0, 0.15, 0.25, 0.75, 0.85, 0.95, and 1). It was found that Se increases the doping concentration of K in PbTe as a result of the balance of electronegativity and also lowers the lattice thermal conductivity because of the increased number of point defects. Tuning the composition and carrier concentration to increase the density of states around the Fermi level results in higher Seebeck coefficients for the two valence bands of PbTe(1-y)Se(y). Peak thermoelectric figure of merit (ZT) values of ~1.6 and ~1.7 were obtained for Te-rich K(0.02)Pb(0.98)Te(0.75)Se(0.25) at 773 K and Se-rich K(0.02)Pb(0.98)Te(0.15)Se(0.85) at 873 K, respectively. However, the average ZT was higher in Te-rich compositions than in Se-rich compositions, with the best found in K(0.02)Pb(0.98)Te(0.75)Se(0.25). Such a result is due to the improved electron transport afforded by heavy K doping with the assistance of Se. 相似文献