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NUMERICAL SIMULATION OF 3-D TURBULENT FLOW IN THE MULTI-INTAKES SUMP OF THE PUMP STATION

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Journal of Hydrodynamics 2007年第1期19卷 42-47页

作者： CHEN Hong-xun SHEN xin-rong Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

In this article, a numerical model forthree-dimensional turbulent flow in the sump of the pumpstation was presented. A reasonable boundary condition for the flow in the sump with several water intakes at different flowrates was proposed. The finite volume method was employed tosolve the governing equations with the body fitted gridgenerated by the multi-block grid technique. By using theFluent software, the fluid flow in a model sump of the pumpstation was calculated. Compared with the experimental result,the numerical result of the example is fairly good.

关键词： pumping station sump suction pipe turbulentmodel numerical simulation

Analysis of the heat transfer in unsymmetrically heated triangular microchannels in slip flow regime

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Science China(Technological Sciences) 2004年第4期47卷 436-446页

作者： ZHU xun LIAO Qiang xin Mingdao Institute of Engineering Thermophysics Chongqing University Chongqing 400044 China Institute of Engineering Thermophysics Chongqing University Chongqing 400044 China Institute of Engineering Thermophysics Chongqing University Chongqing 400044 China

A theoretical analysis of heat transfer characteristics is presented for the fully developed laminar flow of the incompressible gas in the triangular microchannels heated unsymmetrically with constant axial heat flux. Through solving the energy equation with temperature jump boundary conditions in slip flow regime by virtue of a computation- oriented method of the orthonormal function analysis, the dimensionless temperature profiles and the average Nusselt number for various thermal boundary conditions are obtained. The effects of Knudsen number, aspect ratio, and thermal boundary conditions on the heat transfer are discussed. The calculated results show that the orthonormal function method can be used to study the heat transfer characteristics of the unsymmetrically heated triangular microchannels. The average Nusselt number in triangular microchannels is lower for slip flow than for no-slip flow, and decreases with increasing Knudsen number. The aspect ratios and thermal boundary conditions of triangular microchannels have significant influences on the change of average Nusselt numbers with the increase in the Knudsen number. For the equilateral triangular microchannels, the decrease of the Nusselt number ratio due to temperature jump is smaller at large Knudsen number and larger at small Knudsen number on the boundary condition of bottom wall heated alone as compared with the one on the boundary condition of two heated hypotenuse walls. The correlations of the average Nusselt number with the Knudsen number for equilateral triangular microchannels are obtained.

关键词： slip flow regime, triangular microchannel, unsymmetrical thermal boundary, heat transfer.

Modeling of Steam Turbine’s Governing System during Main Steam Valve Activity Test and its Application 36

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Modeling of Steam Turbine’s Governing System during Main St...

Study of Enhanced Fine Coal De-sulphurization and De-ashing by Ultrasonic Flotation

第36届中国控制会议

作者： SHENG Kai ZHENG Zhong ZHOU Nianguang xun xin State Grid Hunan Electric Power Corporation Research Institute Hunan Xiangdian Test & Research Institute Co.Ltd State Grid Hunan Electric Power Corporation

ISBN: (纸本)9781538629185

Model of a 300MW thermal power unit’s governing system of steam turbine was established to analyze its load fluctuation during main steam valve activity test. The model contains three sub-models. They are model of turbine’s governor during main steam valve activity test, model of governing valve, model of steam turbine considering governing valve’s discharge characteristic. Based on the established model, the cause of load fluctuation and optimization method were determined. Then the optimization method was applied to actual main steam valve activity test. The test result indicated that load fluctuation was obviously suppressed after optimization.

关键词： main steam valve activity test load fluctuation steam turbine governing system optimization

来源： cnki会议评论

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Journal of China University of Mining and Technology 2007年第3期17卷 358-362页

作者： KANG Wen-ze xun Hai-xin CHEN Jun-tao School of Resource and Environment Heilongjiang Institute of Science and Technology Harbin Heilongjiang 150027 China

The feasibility of using ultrasound to enhance the performance of de-sulphurization and de-ashing during slime flotation was investigated. The Setararn C80 calorimeter, the contact angle gauge DCAT21 and an electrophoresis apparatus were used to study the surface nature of coal, pyrite and refuse before and after ultrasonic conditioning. The yield, ash and sulfur contents of equally sized coal slimes were also measured before and after ultrasonic conditioning. The results show that ultrasonic conditioning can drive the separation of pyrite and refuse from coal. After ultrasonic conditioning the hydrophobicity of coal and hydrophilicity of pyrite and refuse increase. The perfect index of flotation, the perfect index of de-sulphurization and the percentage of de-sulphurization increase by 22.51%, 25.36% and 2.49%, respectively. This study shows that ultrasonic conditioning can enhance the performance of de-sulphurization and de-ashing of coal flotation methods.

关键词： ultrasonic separating hydrophobicity de-sulphurization de-ashing

Preparation and Electrochemical Properties of xLi2MnO3·（1-x）LiMn2O4 Composites

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Chemical Research in Chinese Universities 2013年第2期29卷 307-310页

作者： YAO Su-mei ZHANG Jing-wen GUO xun QIU xin-ping Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of Chemistry Tsinghua University Beo'ing 100084 P. R. China

Li2MnO3-doped spinel LiMn2O4 composites were synthesized by sol-gel method to improve the electro- chemical performance of LiMn2O4. The microstructures, morphologies and electrochemical performance of the obtained xLi2MnO3.（1-x）LiMnEO4 composites were characterized by X-ray diffraction（XRD）, scan electron microsco- py（SEM） and a galvanostatic charge-discharge process. It was found that both Li2MnO3 and LiMn2O4 components exist in xLi2MnO3·（1-x）LiMn204（O〈x〈1） composites. The 0.3Li2MnO3·0.7LiMnEO4 composite shows the optimized electrochemical performance, including discharge capacity and cycle stability. It was demonstrated that LiEMnO3-doped spinel LiMn204 cathode material can work at wide potential window with quite good capacity reten- tion and considerably larger reversible capacity compared to single-phase LiMn204 component.

关键词： Spinel Composite Electrochemical performance

Effects from changes in pulp nature after ultrasonic conditioning on high-sulfur coal flotation

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Mining Science and Technology 2009年第4期19卷 498-502,507页

作者： KANG Wen-ze xun Hai-xin KONG Xiao-hong LI Ming-ming Resource and Environment Department Heilongjiang Institute of Science and Technology Harbin Heilongjiang 150027 China Mineral Processing Major Laboratory for Education Department of Heilongjiang Province Harbin Heilongjiang 150027 China

A study of the effects of the pulp nature on desulphurization and de-ashing during high-sulfur coal flotation is described in this paper. Highlighted are the use of a solution oxygen gauge, a pH value gauge and a surface tension gauge to investigate changes in the pulp nature related to changes in the oxygen content, the pH value and the interfacial tension. The temperature be- fore and after ultrasonic conditioning was also investigated. The results showed that ultrasonic conditioning resulted in a decrease in the oxygen content and the interracial tension and an increase in the pH value and the temperature of the pulp. The perfect index of flotation and the perfect index of desulphurization of fine coal increased by 25.19% and 18.03%, respectively, after the pulp was ultrasonically conditioned. This study shows that ultrasonic conditioning can change the pulp nature and enhance the degree of desulphurization during high-sulfur coal flotation.

关键词： ultrasonic treatment pulp perfect index of flotation perfect index of desulphurization

The Effect of Career Plateau on Chinese Employees＇ Affective Commitment： An Indigenous Career Plateau Scale and Two-Mediator Model

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Frontiers of Business Research in China 2014年第3期8卷 346-366页

作者： Baoguo Xie xinxin Lu Wenxia Zhou xun xin School of Labor and Human Resources Renmin University of China Beijing 100872 China

The two-dimensional （hierarchical and job content） model have been predominating the extant career plateau literature. However, based on Schein＇s cone-shaped organizational mobility model, we contend that stagnation in organizational centrality （inclusive plateau） may be another dimension of career plateau. Furthermore, grounded in social exchange theory and need-satisfaction models, we aim to examine the effects of career plateau on affective commitment and underlying mechanisms. In Study 1, based on a sample of 219 employees from different professions, we developed a primary validation of our three- dimensional career plateau scale. In Study 2, we examined our hypothesized model with another dataset of 288 employees. The results suggest that job satisfaction fully mediates the relationship between the job content plateau, the inclusive plateau and affective commitment. The analysis demonstrates that the specific indirect effect of job content plateauing and inclusion on affective commitment through intrinsic job satisfaction was greater than through extrinsic job satisfaction. However, the hypothesis regarding the relationship between hierarchical plateau and affective commitment was not supported, when another two dimensions of career plateau were added to the model. Our findings provide some theoretical and practical implications.

关键词： career plateau three-factor structure job satisfaction affectivecommitment

从一个实例看分散控制错误引发强迫功率振荡的可能性

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电力系统自动化 2015年第19期39卷 155-159页

作者：盛锴寻新国网湖南省电力公司电力科学研究院湖南省长沙市410007

针对一起由分散控制系统设置错误引发的机组安全事故,分析了事故的发生原因,并建立了汽轮机调节系统模型,利用实时仿真平台再现了事故经过。进一步地,利用电力系统综合分析程序PSASP建立的单机无穷大系统研究并分析了此时分散控制系统... 详细信息

针对一起由分散控制系统设置错误引发的机组安全事故,分析了事故的发生原因,并建立了汽轮机调节系统模型,利用实时仿真平台再现了事故经过。进一步地,利用电力系统综合分析程序PSASP建立的单机无穷大系统研究并分析了此时分散控制系统故障引起电力系统强迫功率振荡的可能性。研究结果表明,分散控制系统故障可能造成电力系统强迫功率振荡,且分散控制系统控制器的运算周期影响了强迫功率振荡幅度。

关键词：分散控制系统汽轮机调节系统强迫功率振荡运算周期

社会学习理论视角下领导-下属之间的工作重塑传递效应研究

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中国人力资源开发 2017年第3期34卷 18-27页

作者：辛迅西南政法大学管理学院

本研究考察了团队领导的工作重塑对下属工作重塑的影响,揭示了工作重塑在领导-下属之间传导的"黑箱"。根据来自企业中64个工作团队、共250名员工的领导-下属配对数据,检验了一个跨层次的调节中介模型。研究结果表明:(1)团队中的领导工... 详细信息

本研究考察了团队领导的工作重塑对下属工作重塑的影响,揭示了工作重塑在领导-下属之间传导的"黑箱"。根据来自企业中64个工作团队、共250名员工的领导-下属配对数据,检验了一个跨层次的调节中介模型。研究结果表明:(1)团队中的领导工作重塑正向影响员工工作重塑;(2)角色榜样在领导工作重塑与员工工作重塑的关系中起着部分中介作用;(3)授权型领导风格正向调节了角色榜样在领导工作重塑和员工工作重塑之间的中介效应。最后,对研究结论进行讨论,总结了本文的理论贡献和实践意义,并提出了研究局限以及对未来研究的展望。

关键词：领导一下属工作重塑角色榜样授权型领导风格传递效应