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Journal of Thermal Science 2011年第4期20卷 304-311页

作者： Jun LI Hao SUN jinshan wang Zhenping FENG Institute of Turbomachinery Xi＇an Jiaotong University Xi＇an 710049 CHINA

The steady and unsteady leakage flow and heat transfer characteristics of the rotor blade squealer tip were conducted by solving Reynolds-Averaged Navier-Stokes （RANS） equations with k-co turbulence model. The first stage of GE-E3 engine with squealer tip in the rotor was adopted to perform this work. The tip clearance was set to be 1% of the rotor blade height and the groove depth was specified as 2% of the span. The results showed that there were two vortexes in the tip gap which determined the local heat transfer characteristics. In the steady flow field, the high heat transfer coefficient existed at several positions. In the unsteady case, the flow field in the squealer tip was mainly influenced by the upstream wake and the interaction of the blades potential fields. These unsteady effects induced the periodic variation of the leakage flow and the vortexes, which resulted in the fluctuation of the heat transfer coefficient. The largest fluctuation of the heat transfer coefficient on the surface of the groove bottom exceeded 16% of the averaged value on the surface of the squealer tip.

关键词： Gas Turbine Blade Squealer Tip Leakage Flow Heat Transfer Numerical Simulation

SOME COMPARISONS BETWEEN GENERALIZED ORDER STATISTICS

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Applied Mathematics(A Journal of Chinese Universities) 2007年第3期22卷 325-333页

作者： Qiu Guoxin wang jinshan Mathematics Section Dept. of Basic Courses Artillery College of PLA Hefei 230031 China

Some stochastic comparisons of generalized order statistics under the right spread order, the location independent riskier order and the total time transform order are investigated in this paper. The underlying distributions and parameters on which generalized order statistics are based are also surveyed to obtain the conditions for increasing the expectations of spacings between the first two generalized order statistics and between the last two generalized order statistics.

关键词： generalized order statistics location independent riskier order right spread order total time transform order.

High Quality Audio Object Coding Framework Based on Non-Negative Matrix Factorization

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China Communications 2017年第9期14卷 32-41页

作者： Tingzhao Wu Ruimin Hu Xiaochen wang Shanfa Ke jinshan wang National Engineering Research Center for Multimedia Software School of Computer ScienceWuhan University Hubei Key Laboratory of Multimedia and Network Communication Engineering Wuhan University Collaborative Innovation Center of Geospatial Technology

Object-based audio coding is the main technique of audio scene coding. It can effectively reconstruct each object trajectory, besides provide sufficient flexibility for personalized audio scene reconstruction. So more and more attentions have been paid to the object-based audio coding. However, existing object-based techniques have poor sound quality because of low parameter frequency domain resolution. In order to achieve high quality audio object coding, we propose a new coding framework with introducing the non-negative matrix factorization(NMF) method. We extract object parameters with high resolution to improve sound quality, and apply NMF method to parameter coding to reduce the high bitrate caused by high resolution. And the experimental results have shown that the proposed framework can improve the coding quality by 25%, so it can provide a better solution to encode audio scene in a more flexible and higher quality way.

关键词： object-based audio coding non-negative matrix factorization audio scenecoding

Uniform nanoplating of metallic magnesium film on titanium dioxide nanotubes as a skeleton for reversible Na metal anode

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International Journal of Minerals,Metallurgy and Materials 2023年第10期30卷 1868-1877页

作者： jinshan wang Feng Li Si Zhao Lituo Zheng Yiyin Huang Zhensheng Hong Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials College of Physics and EnergyFujian Normal UniversityFuzhou 350117China Academy of Carbon Neutrality of Fujian Normal University Fuzhou 350117China

To meet the low-cost concept advocated by the sodium metal anode,this paper reports the use of a pulsed electrodeposition technology with ionic liquids as electrolytes to achieve uniform nanoplating of metallic magnesium films at around 20 nm on spaced titanium dioxide(TiO_(2))nanotubes(STNA-Mg).First,the sodiophilic magnesium metal coating can effectively reduce the nucleation overpotential of sodium ***,three-dimensional STNA can limit the volume expansion during sodium metal plating and stripping to achieve the ultrastable deposition and stripping of sodium metals with a high Coulombic efficiency of up to 99.5%and a small voltage polarization of 5 mV in symmetric Na||Na *** addition,the comparative study of sodium metal deposition behavior of STNA-Mg and STNA-Cu prepared by the same route further confirmed the advantage of magnesium metal to guide sodium metal ***,the prepared STNA-Mg-Na metal anode and commercial sodium vanadium phosphate cathode were assembled into a full cell,delivering a discharge capacity of 110.2 mAh·g^(-1)with a retention rate of 95.6%after 110 cycles at 1C rate.

关键词： sodium metal anode titanium dioxide nanotubes skeleton electrodeposition metallic magnesium coating

The visual fiducial based pose estimation of mobile manipulator in large-scale components manufacturing

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Science China(Technological Sciences) 2021年第10期64卷 2186-2199页

作者： GONG ZeYu YU SuPu TAO Bo GU ZhenFeng wang jinshan DING Han State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The accurate estimation of the end-effector’s pose in large operating spaces is the key for the mobile manipulator to realize efficient manufacturing of large and complex *** propose a novel pose tracking method in large-range using visual fiducial markers,and further propose the layout optimization method for the encoded fiducial markers.A metric named orientational dilution of precision(ODOP)is proposed to evaluate the magnification of the pose estimation error compared with the measurement error of the coded fiducial *** distribution pattern of the coded markers is analyzed based on ODOP,and the square-shaped layout is determined to be a satisfactory distribution pattern for the minimum positioning unit of markers,and the side length of the square-shaped layout is further *** simulations and experiments prove the effectiveness of the ODOP ***,the square-shaped layout and the designed distribution density for positioning coded markers are adopted to realize the high-precision measurement of large components by the mobile manipulator.

关键词： pose estimation orientational dilution of precision mobile manipulator visual fiducial layout optimization

Global Dynamics of a Multi-group SEIR Epidemic Model with Infection Age

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Chinese Annals of Mathematics,Series B 2021年第6期42卷 833-860页

作者： Vijay Pal BAJIYA Jai Prakash TRIPATHI Vipul KAKKAR jinshan wang Guiquan SUN Department of Mathematics Central University of RajasthanBandar Sindri-305817KishangarhAjmerRajasthanIndia Complex Systems Research Center Shanxi UniversityTaiyuan 030006China Department of Mathematics North University of ChinaTaiyuan 030051China Complex Systems Research Center Shanxi UniversityTaiyuan 030006China.

Consider the heterogeneity(e.g.,heterogeneous social behaviour,heterogeneity due to different geography,contrasting contact patterns and different numbers of sexual partners etc.)of host population,in this paper,the authors propose an infection age multigroup SEIR epidemic *** model system also incorporates the feedback variables,where the infectivity of infected individuals may depend on the infection *** the direction of mathematical analysis of model,the basic reproduction number R_0 has been *** global stability of disease-free equilibrium and endemic equilibrium have been established in the term of R_(0).More precisely,for R_(0)≤1,the disease-free equilibrium is globally asymptotically stable and for R_(0)>1,they establish global stability of endemic equilibrium using some graph theoretic techniques to Lyapunov function *** considering a numerical example,they investigate the effects of infection age and feedback on the prevalence of the *** result shows that feedback parameters have different and even opposite effects on different ***,by choosing an appropriate value of feedback parameters,the disease could be eradicated or maintained at endemic ***,the infection age of infected individuals may also change the behaviour of the disease,global stable to damped oscillations or damped oscillations to global stable.

关键词： Multi-group model Infection age Feedback Graph-theoretic approach Lyapunov function

Protective layer for stable lithium-metal anodes at 60 mA·h/cm^(2) and 60 mA/cm^(2) with ion channel and inductive effect

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Journal of Materiomics 2024年第6期10卷 1252-1260页

作者： Xiao Zhang Zhiwei Chen Jiaojiao Han Qiang wang jinshan wang Juhua Luo Jianguang Xu Chi Chen Wei Yao School of Materials Science and Engineering Jiangsu Provincial Key Laboratory of Eco-Environmental MaterialsYancheng Institute of TechnologyYancheng 224051China School of Materials and Energy Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials and Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021China

Contradiction between ultrafast nucleation and deposition rates of lithium(Li)crystals at high rate and heterogeneity of Li^(+)flux resulting from concentration polarization has compromised the performance of Li metal anodes especially at high areal capacity and current ***,multifunctional protective layer consisting of MoO_(3) nanobelt films(MoO_(3)-NF)is introduced on the surface of Li by a simple rolling *** strong binding energy between Li and MoO_(3) guides the homogeneous nucleation and deposition of Li,while the nanobelt networks provide effective ion channels for uniform distribution of the Li+*** of the novel multifunctional protective layer,the MoO_(3)-NF@Li anodes demonstrate a remarkable stability for 800 h with ultralow overpotential of 159 mV at extreme harsh conditions of 60 mA·h/cm^(2) and 60 mA/cm^(2).MoO_(3)-NF@Li||LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2) full-cells can run 100 cycles with a superior capacity retention of 84.2%under practical test conditions,demonstrating great potential for high output and energy-density metal batteries.

关键词： Multifunctional protective layer Ion channel Inductive effect High areal capacity Li metal anodes

Effect of Sb on the grain refinement and tensile properties of Mg-10Zn-5Al alloys

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China Foundry 2010年第3期7卷 236-240页

作者： Zhang Zhaoguang Zhang jinshan Liu Yali wang Xing Zhou Cuilan College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

In the present research, the Sb-alloying method was adopted, and the grain re finement and tensile properties of as-cast Mg-10Zn-5Al alloys with varying Sb addition were *** results showed that with the Sb addition, a new phase (Mg3Sb2) of high melting point forms in the alloy beside the α-Mg matrix, τ-Mg32(Al, Zn)49 phase and φ-Al2Mg5Zn2 *** an appropriate amount of Sb addition, the morphologies of the secondary phases and the matrix are changed and the grains are *** Sb addition is 0.6wt.%, both ambient and high temperature tensile strengths of the alloy reach their *** hardness of the alloy increases with the increasing of Sb *** proper addition of Sb, the tensile failure mode of the alloy changes from cleavage fracture to quasi-cleavage fracture, showing good enhancement effect.

关键词： ZA105 magnesium alloy microstructure tensile properties Mg3Sb2

冷却表面温差对高温质子交换膜燃料电池性能的影响

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化工学报 2024年第5期75卷 2026-2035页

作者：王金山王世学朱禹天津大学机械工程学院天津300350 天津大学国家储能技术产教融合创新平台天津300350

通过建立高温质子交换膜燃料电池数学模型,模拟了冷却表面存在不同温差时燃料电池内热-电-质的传输特性,分析了温差对电池内温度分布、氧浓度分布、极化曲线、膜质子电导率和电流密度的影响。结果表明:膜内温度和质子电导率随着冷却表... 详细信息

通过建立高温质子交换膜燃料电池数学模型,模拟了冷却表面存在不同温差时燃料电池内热-电-质的传输特性,分析了温差对电池内温度分布、氧浓度分布、极化曲线、膜质子电导率和电流密度的影响。结果表明:膜内温度和质子电导率随着冷却表面温度的降低而降低;催化层内的局部氧浓度随着冷却表面温差(即温度梯度)的增大而增大,但电流密度受温度及反应物浓度双重因素影响,电流密度及功率密度随着温度梯度的增大而下降。当冷却表面温度梯度从0增加至0.82 K/cm时,峰值功率密度从0.578 W/cm2下降到0.523 W/cm2,下降了9.52%。控制工作电压大于0.5 V、温度梯度小于0.20 K/cm时可获得较好的电流密度均匀性。当工作电压为0.5 V,冷却表面温度梯度为0.20 K/cm时,电流密度均匀性为92.71%。

关键词：燃料电池传热传质数值模拟电流密度均匀性

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用环糊精合成楔筒状主体分子新模型

化学学报 2002年第8期60卷 1536-1538页

作者：郝爱友王金山山东大学化学与化工学院济南250100 山东师范大学化学系济南250014

用四醋酸铅将七元 (6 O 二甲基叔丁基硅基 ) β 环糊精选择氧化、并用三氟化硼乙醚脱硅基保护基后 ,再经分离、纯化 ,可获得具有“楔筒状”空腔的单 2 ,3 二醛基 β 环糊精 .单 2 ,3 二醛基 β 环糊精较 β 环糊精有更好的水溶性 ... 详细信息

用四醋酸铅将七元 (6 O 二甲基叔丁基硅基 ) β 环糊精选择氧化、并用三氟化硼乙醚脱硅基保护基后 ,再经分离、纯化 ,可获得具有“楔筒状”空腔的单 2 ,3 二醛基 β 环糊精 .单 2 ,3 二醛基 β 环糊精较 β 环糊精有更好的水溶性 .用单 2 ,3 二醛基 β 环糊精作TLC流动相手性添加剂时 ,可将肾上腺素对映体在硅胶薄层板上有效拆分 .

关键词：主体分子 β-环糊精单-2,3-二醛基-β-环糊精楔筒状大环分子主客体化学