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微流控法制备示踪微球用于液滴传质行为

化学工程 2025年第1期53卷 29-35页

作者：孙桂芳刘康佳刘向东姚峰张程宾扬州大学电气与能源动力工程学院江苏扬州225127 苏州科技大学低碳能源高效转化与利用省高校重点实验室江苏苏州215009 东南大学能源与环境学院江苏南京210096

粒子示踪法是可视化液液对流传质过程的重要手段,但传统方法制备的聚苯乙烯示踪微球存在尺寸分布不均匀、表面光洁度不高等问题。采用微流控方法制备聚苯乙烯示踪微球,并与商用聚苯乙烯示踪微球进行性能对比,进一步利用所制备的示踪微... 详细信息

粒子示踪法是可视化液液对流传质过程的重要手段,但传统方法制备的聚苯乙烯示踪微球存在尺寸分布不均匀、表面光洁度不高等问题。采用微流控方法制备聚苯乙烯示踪微球,并与商用聚苯乙烯示踪微球进行性能对比,进一步利用所制备的示踪微球开展液滴对流传质行为研究。结果表明:基于微流控技术制备的示踪微球表现出优异的单分散性,相较于商用聚苯乙烯示踪微球单分散性提升约17%,且在球形度和表面光洁度方面均优于商用聚苯乙烯示踪微球。借助示踪微球在不同质量分数的冰乙酸-水混合溶液下观察到Rayleigh-Bénard效应主导、过渡模式和Marangoni效应主导3种对流传质模式,其中Rayleigh-Bénard对流主要受浮力/重力控制着液滴内部的流体流动,在液滴内部形成对称大涡流组结构,在以Marangoni效应为主导的传质过程中的流体流动主要是由于界面张力梯度产生的,而过渡模式则是由于浮力和重力与界面张力之间的相互竞争所导致的。

关键词：微流控微球液滴对流传质

CONSENSUS AND r-CONSENSUS PROBLEMS FOR SINGULAR SYSTEMS

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Journal of Systems Science & Complexity 2014年第2期27卷 252-262页

作者： ZHANG Lequn feng Jun-e yao Juan School of Mathematics Shandong University

In this paper, the problem of consensus for continuous time singular systems of multi-agent networks is considered. The definition of r-consensus is introduced for singular systems of multi-agent networks. Firstly, linear systems with algebraic constraints are considered, and the corresponding results about consensus and average-consensus are derived. Then r-consensus and consensus problems of singular systems are investigated. Sufficient conditions of r-consensus and consensus are obtained,respectively. Finally, an illustrative example is given to show the effectiveness of the proposed method.

关键词： Balanced graphs consensus r-consensus singular systems strong connected graphs.

HIGH RESOLUTION LASER SPECTROSCOPY STUDY OF THE l(2,-1)TYPE RESONANCE IN CH_3Fv_5 BAND

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Chinese Physics Letters 1984年第2期1卷 69-72页

作者： ZHAO yao SHEN Zhiye ZHU Qing-shi ZHANG cun-hao Dalian Institute of Chemical Physics Academia SinicaDalian

The high resolution laser spectroscopy study on the l(2,-1)type Coriolis resonance in CH_(3)Fv_(5)RQO and pp_(3)was carried *** improved value of E5 is obtained,E_(5)=2.3892(9)x10^(-3)cm^(-1).

关键词： CH3F LASER value

Symplectic system based analytical solution for bending of rectangular orthotropic plates on Winkler elastic foundation

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Acta Mechanica Sinica 2011年第6期27卷 929-937页

作者： Wei-An yao Xiao-Fei Hu feng Xiao State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology 116024 Dalian China Department of Computer Science Dalian Medical University 116044 Dalian China

This paper analyses the bending of rectangular orthotropic plates on a Winkler elastic *** definition of symplectic inner product and symplectic space formed by generalized displacements establish dual variables and dual equations in the symplectic *** operator matrix of the equation set is proven to be a Hamilton operator *** of variables and eigenfunction expansion creates a basis for analyzing the bending of rectangular orthotropic plates on Winkler elastic foundation and obtaining solutions for plates having any boundary *** is discussion of symplectic eigenvalue problems of orthotropic plates under two typical boundary conditions,with opposite sides simply supported and opposite sides *** equations of eigenvalues and symplectic eigenvectors in analytical form *** solutions using two examples are presented to show the use of the new methods described in this *** verify the accuracy and convergence,a fully simply supported plate that is fully and simply supported under uniformly distributed load is used to compare the classical Navier method,the Levy method and the new *** show that the new technique has good accuracy and better convergence speed than other methods,especially in relation to internal forces.A fully clamped rectangular plate on Winkler foundation is solved to validate application of the new methods,with solutions compared to those produced by the Galerkin method.

关键词： Orthotropic plate Symplectic space Winklerelastic foundation Analytical solution

Adaptive Backstepping Terminal Sliding Mode Control Method Based on Recurrent Neural Networks for Autonomous Underwater Vehicle

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 228-243页

作者： Chao Yang feng yao Ming-Jun Zhang College of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China

The trajectory tracking control problem is addressed for autonomous underwater vehicle(AUV) in marine environ?ment, with presence of the influence of the uncertain factors including ocean current disturbance, dynamic modeling uncertainty, and thrust model errors. To improve the trajectory tracking accuracy of AUV, an adaptive backstepping terminal sliding mode control based on recurrent neural networks(RNN) is proposed. Firstly, considering the inaccu?rate of thrust model of thruster, a Taylor’s polynomial is used to obtain the thrust model errors. And then, the dynamic modeling uncertainty and thrust model errors are combined into the system model uncertainty(SMU) of AUV; through the RNN, the SMU and ocean current disturbance are classified, approximated online. Finally, the weights of RNN and other control parameters are adjusted online based on the backstepping terminal sliding mode controller. In addition, a chattering?reduction method is proposed based on sigmoid function. In chattering?reduction method, the sigmoid function is used to realize the continuity of the sliding mode switching function, and the sliding mode switching gain is adjusted online based on the exponential form of the sliding mode function. Based on the Lyapu?nov theory and Barbalat’s lemma, it is theoretically proved that the AUV trajectory tracking error can quickly converge to zero in the finite time. This research proposes a trajectory tracking control method of AUV, which can e ectively achieve high?precision trajectory tracking control of AUV under the influence of the uncertain factors. The feasibility and e ectiveness of the proposed method is demonstrated with trajectory tracking simulations and pool?experi?ments of AUV.

关键词： Autonomous underwater vehicle(AUV) Trajectory tracking Neural networks Backstepping method Terminal sliding mode Adaptive control

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变频驱动游梁有杆泵系统仿真与频率优化研究

石油机械 2025年第1期53卷 98-105页

作者：张传新姚金杭孔有为褚浩元檀朝东冯子明冯钢新疆油田分公司工程技术研究院中国石油大学(北京)石油工程学院中国石油大学(北京)人工智能学院温州大学机电工程学院西安中控天地科技开发有限公司

针对电机匀速驱动游梁抽油机运行过程中周期性交变载荷变化大、系统能耗高及故障多的问题,分析了电机变频驱动对抽油机运动规律、悬点载荷、变速箱扭矩及电机功率的影响,建立了变频控制抽油系统动态能耗的仿真模型。以电机输出功率均方... 详细信息

针对电机匀速驱动游梁抽油机运行过程中周期性交变载荷变化大、系统能耗高及故障多的问题,分析了电机变频驱动对抽油机运动规律、悬点载荷、变速箱扭矩及电机功率的影响,建立了变频控制抽油系统动态能耗的仿真模型。以电机输出功率均方根最小、输出功率峰值最小和负发电最小为目标函数,综合考虑平均频率不变、上下冲程时间分配、频率范围等约束条件,建立了周期运行频率优化设计的数学模型,并采用粒子群优化算法求解周期频率分布函数的傅里叶系数,即周期运行频率分布。实例分析表明:优化实时频率可以显著改善抽油机的动力性能,悬点载荷、曲柄扭矩和输出功率的峰值均有所降低;电机平均输出功率降低16.2%,负发电减少14.77%,节能效果显著。所得结果可为变频驱动游梁有杆泵系统的设计及应用提供参考。

关键词：游梁抽油机井动态能耗仿真频率分布悬点粒子群算法

Effect of content and spin state of iron on electronic properties and floatability of iron-bearing sphalerite:A DFT+U study

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International Journal of Mining Science and Technology 2023年第12期33卷 1563-1571页

作者： yao feng Zhuofan Li Jianhua Chen Ye Chen State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures School of Chemistry&Chemical EngineeringGuangxi UniversityNanning 530004China MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials Guangxi UniversityNanning 530004China School of Resources Environment and MaterialsGuangxi Higher School Key Laboratory of Minerals EngineeringGuangxi UniversityNanning 530004China

Iron is an impurity widely occurred in sphalerite,and its effect on sphalerite flotation is *** this work,the effects of iron content and spin state on electronic properties and floatability of iron-bearing sphalerite are comprehensively studied using density functional theory Hubbard U(DFT+U)calculations combined with coordination chemistry *** band gap of ideal sphalerite is 3.723 eV,and thus electron transition is difficult to occur,resulting in poor *** results suggest the band gap of sphalerite decreases with increasing iron *** low iron content,the decreased band gap facilitates electron transition;at this case,Fe^(2+)in a high-spin state possesses oneπelectron pair,which can form a weakπ-backbonding with xanthate,causing increasing ***,for medium and high iron-bearing sphalerite,with the further decrease of band gap,Fe^(2+)is oxidized to Fe^(3+)due to electrochemical interaction,and henceπ-backbonding is eliminated,leading to lower floatability of iron-bearing sphalerite,which is consistent with the flotation experimental *** work could give a deeper understanding of how sphalerite flotation behaviors are affected by iron content.

关键词： Sphalerite Iron-bearing sphalerite Iron content Spin state Density functional theory

Observation scheduling problem for AEOS with a comprehensive task clustering

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Journal of Systems Engineering and Electronics 2021年第2期32卷 347-364页

作者： CHANG Zhongxiang ZHOU Zhongbao yao feng LIU Xiaolu School of Business Administration Hunan UniversityChangsha 410082China Institute of Data Science and Decision Optimization Hunan UniversityChangsha 410082China Department of Mathematics Simon Fraser UniversitySurrey V3T 0A3Canada School of System Engineering National University of Defense TechnologyChangsha 410073China

Considering the flexible attitude maneuver and the narrow field of view of agile Earth observation satellite(AEOS)together,a comprehensive task clustering(CTC)is proposed to improve the observation scheduling problem for AEOS(OSPFAS).Since the observation scheduling problem for AEOS with comprehensive task clustering(OSWCTC)is a dynamic combination optimization problem,two optimization objectives,the loss rate(LR)of the image quality and the energy consumption(EC),are proposed to format OSWCTC as a bi-objective optimization *** the power of an adaptive large neighborhood search(ALNS)algorithm with a nondominated sorting genetic algorithm II(NSGA-II),a bi-objective optimization algorithm,ALNS+NSGA-II,is developed to solve *** on the existing instances,the efficiency of ALNS+NSGA-II is analyzed from several aspects,meanwhile,results of extensive computational experiments are presented which disclose that OSPFAS considering CTC produces superior outcomes.

关键词： observation scheduling comprehensive task clustering(CTC) bi-objective optimization image quality energy consumption(EC)

Response mechanism study of alternate ZrC-10vol.%SiC/ZrC-70vol.%SiC coatings with various sublayer thicknesses for cyclic and long-term thermal exposure

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Journal of Materials Science & Technology 2023年第9期140卷 153-162页

作者： Guanghui feng Xiyuan yao Yulan Yu Hejun Li State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi’an 710072China

To explore the influence of sublayer numbers on the structure evolution and thermal stress level,an alternate coating consisting of ZrC-10 vol.%SiC and ZrC-70 vol.%SiC sublayers was designed in this *** a basically consistent general thickness,three coatings constituted by 2,4 and 6 sublayers were prepared by plasma spraying,which then were assessed using an oxyacetylene torch under cyclic and long-term *** coating with 6 sublayers was supposed to be the one with the best ablation property,finite element analysis also evidenced its least thermal stress among all these *** being ablated for 240 s,the linear and mass ablation rates of the coating with 6 sublayers decreased by 51.27%and 14.41%as compared to that with 4 ***-test analysis proved the existence of Si-based products,which help the outmost surface to develop a dense ***,the yielded alternate dense/porous scale had a preferable toughness,allowing it to maintain a good integrity.

关键词： Alternate coating Sublayer numbers Carbon/carbon composites High-temperature test Plasma spraying