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Gravity-Driven Instability in a Liquid Film Overlying an Inhomogeneous Porous Layer

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Chinese Physics Letters 2011年第2期28卷 144-147页

作者： ZHAO Si-Cheng liu qiu-sheng NGUYEN-THI Henri BILLIA Bernard Key Laboratory of Microgravity Institute of MechanicsChinese Academy of SciencesBeijing 100190 IM2NP UMR CNRS 6137Universitéd’Aix-Marseille III13397 Marseille Cedex 20France

A new model consisting of a liquid film overlying a saturated and inhomogeneous porous layer is *** concentrate on effects of inhomogeneity on transition of instability *** of the averaged porosity and the gradient of porosity distribution on the instability behaviors of a liquid-porous layer system are *** average permeability of the porous layer is a key factor to determine the penetration of convection in the system.

关键词： porosity porous layer

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蒸发两层流系统的对流不稳定性分析

工程热物理学报 2006年第3期27卷 429-432页

作者：刘荣刘秋生中国科学院力学研究所国家微重力实验室北京100080

关于蒸发液层的Rayleigh-Marangoni-Benard不稳定性的研究中,早期文献中普遍采用的是单层流模型。近年来,一些学者采用两层流模型对蒸发稳定性进行了理论分析,有的文献中没有考虑蒸发率与饱和蒸汽压的耦合关系,所以得到的结果不能完全... 详细信息

关于蒸发液层的Rayleigh-Marangoni-Benard不稳定性的研究中,早期文献中普遍采用的是单层流模型。近年来,一些学者采用两层流模型对蒸发稳定性进行了理论分析,有的文献中没有考虑蒸发率与饱和蒸汽压的耦合关系,所以得到的结果不能完全反应蒸发对系统稳定性的影响。本文建立了一种新的两层流模型,考虑了界面变形对系统稳定性的影响。采用线性稳定性方法对带有蒸发界面的两层流的Rayleigh-Marangoni-Benard对流不稳定性进行了分析,得到了临界 Marangoni数与波数的关系,重点讨论了蒸发系数以及重力对汽液两层流系统的不稳定性的影响。

关键词： Rayleigh—Marangoni—Bénard对流线性稳定性蒸发界面界面变形

两相流层的Marangoni-Bénard不稳定性分析

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工程热物理学报 2005年第2期26卷 264-266页

作者：刘荣刘秋生中国科学院力学研究所国家微重力实验室北京100080

关于液层的Marangoni-Bénard不稳定性的研究中,现有文献中普遍采用的是单层流模型。本文建立了一种新的两层流模型,采用线性稳定性方法对带有蒸发界面的两层流的Marangoni-Bénard对流不稳定性进行了分析,得到了在不同蒸发量下临界Mara... 详细信息

关于液层的Marangoni-Bénard不稳定性的研究中,现有文献中普遍采用的是单层流模型。本文建立了一种新的两层流模型,采用线性稳定性方法对带有蒸发界面的两层流的Marangoni-Bénard对流不稳定性进行了分析,得到了在不同蒸发量下临界Marangoni数与波数的关系,重点讨论了蒸发速率对汽液两层流系统Marangoni-Bénard不稳定性的影响。

关键词： Marangoni-Bénard对流不稳定性蒸发

高频振动影响下双层Marangoni-Bénard对流稳定性研究

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北京交通大学学报 2006年第4期30卷 6-10,14页

作者：刘秋生王安中国科学院力学研究所北京100080

对高频振动影响下双层Marangoni_Bénard对流进行了线性稳定性理论分析,发现了高频振动对于Marangoni_Bénard对流不稳定性特征的双重影响,并分析了硅油与氟液(FC70)典型双层流体实验系统的不稳定性,其结果显示在一定振动运动或残余重... 详细信息

对高频振动影响下双层Marangoni_Bénard对流进行了线性稳定性理论分析,发现了高频振动对于Marangoni_Bénard对流不稳定性特征的双重影响,并分析了硅油与氟液(FC70)典型双层流体实验系统的不稳定性,其结果显示在一定振动运动或残余重力场下的两层流系统具有更复杂的不稳定现象.

关键词：振动运动 Marangoni-Bènard对流双层流体线性稳定性微重力

Three-Dimensional Linear Instability Analysis of Thermocapillary Return Flow on a Porous Plane

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Chinese Physics Letters 2010年第2期27卷 165-168页

作者：赵思诚刘秋生 NGUYEN-THI Henri BILLIA Bernard Key Laboratory of Microgravity Institute of Mechanics Chinese Academy of Sciences Beijing 100190 IM2NP UMR CNRS 6137 Université d'Aix-Marseille III 13397 Marseille Cedex 20 France

A three-dimensional linear instability analysis of thermocapillary convection in a fluid-porous double layer system, imposed by a horizontal temperature gradient, is performed. The basic motion of fluid is the surface-tension-driven return flow, and the movement of fluid in the porous layer is governed by Darcy＇s law. The slippery effect of velocity at the fluid-porous interface has been taken into account, and the influence of this velocity slippage on the instability characteristic of the system is emphasized. The new behavior of the thermocapillary convection instability has been found and discussed through the figures of the spectrum.

关键词： Fluid dynamics

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M5型喷嘴喷淋液滴粒径分布实验研究

华东电力 2014年第3期42卷 622-626页

作者：刘秋生神华国华(北京)电力研究院有限公司北京100025

喷嘴是使液体雾化的重要装置,在很多领域都有广泛的应用。针对低温多效海水淡化技术中使用的M5型喷嘴的喷淋粒径分布特性,专门设计并建立了特殊的测量系统,进行了常温常压状态下单喷嘴的喷淋液滴粒径分布实验。实验结果表明:同一流量下... 详细信息

喷嘴是使液体雾化的重要装置,在很多领域都有广泛的应用。针对低温多效海水淡化技术中使用的M5型喷嘴的喷淋粒径分布特性,专门设计并建立了特殊的测量系统,进行了常温常压状态下单喷嘴的喷淋液滴粒径分布实验。实验结果表明:同一流量下,在喷淋液滴所形成锥体的横截面上,液滴直径分布成U形;随着流量增加,液滴直径变小,液滴直径分布更加均匀,同时喷嘴的喷淋角度变大;液滴粒径测量时,遮水板之间的间距为2 cm时的流动状况比间距为4 cm时的流动状况波动剧烈。

关键词：低温多效蒸馏 M5型喷嘴液滴粒径分布喷淋张角

Electrocatalytic cleavage of a lignin β-O-4 model compound and coupling with nitrogen-containing aromatics using Prussian blue analogue-derived nickel–cobalt spinel

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Journal of Energy Chemistry 2025年第1期100卷 628-636页

作者： Yi Qi Xueying Chen Bowen liu Xuliang Lin Xueqing qiu Yanlin Qin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light Industry Guangdong University of Technology Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Guangdong Basic Research Center of Excellence for Ecological Security and Green Development Guangdong University of Technology

Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great *** demonstrate the targeted synthesis and cation modulation of NiCo2O4spinel nanoboxes,synthesized via cation exchange and calcination *** catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and *** catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as *** porous architecture and polymetallic composition of the NiCo2O4spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for *** innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT *** work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.

关键词： Spinel Biomass valorization Electrocatalysis Lignin oxidation Coupling

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风场环境下的巡飞弹航迹跟踪运动补偿算法

兵工学报 2016年第12期37卷 2377-2384页

作者：李增彦李小民刘秋生军械工程学院无人机工程系河北石家庄050003 军械工程学院弹药工程系河北石家庄050003

针对巡飞弹航迹跟踪过程受风速、风向影响的问题,在风场环境下,通过建立运动模型,研究并提出了基于变增益虚拟参考点和系统外回路动态补偿的非线性制导律算法。根据制导律参数中固定距离限制的问题,设计了变增益虚拟参考点并分析了航迹... 详细信息

针对巡飞弹航迹跟踪过程受风速、风向影响的问题,在风场环境下,通过建立运动模型,研究并提出了基于变增益虚拟参考点和系统外回路动态补偿的非线性制导律算法。根据制导律参数中固定距离限制的问题,设计了变增益虚拟参考点并分析了航迹跟踪的稳定性条件,针对系统外回路滞后特性设计了动态反馈补偿因子,同时给出了参数计算方法及运动约束条件。通过数学仿真方法分别对无风及有风条件下的制导律进行验证,考虑到实际飞行试验困难的问题,基于vc++搭建了半实物实时仿真平台,通过硬件在回路仿真,验证了航迹跟踪性能。结果表明:改进制导律可有效克服风干扰、具有较高的跟踪精度且易于工程实现。

关键词：兵器科学与技术巡飞弹航迹跟踪非线性制导律运动补偿半实物仿真

Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

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Science China Earth Sciences 2025年第1期68卷 74-93页

作者： Ye YANG Steven A.BINNIE sheng XU Cong-Qiang liu Tibor J.DUNAI Institute of Surface-Earth System Science School of Earth System Science Tianjin University Institute of Geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

关键词： 10Be-derived denudation rate Climate change Tectonic uplift Topographic gradient Asian mountains