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Journal of Thermal Science 2025年第1期 34-49页

作者： WANG Shuang MU lin li xue XIE Jun DONG Ming School of Energy and Power Engineering Dalian University of Technology School of Optical Information and Energy Engineering Wuhan Institute of Technology School of Energy and Environment Shenyang Aerospace University

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method（LES-DEM） *** validity of the LES approach was verified by comparison with available direct numerical simulation（DNS） *** adopted the Johnson-Kendall-Roberts（JKR） contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters（dp=2-20 μm） in the laminar and transition of shear layer（TrSL） flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise（y-direction）.With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

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Amino acid assisted aqueous synthesis of highly stable CsPbBr_(3)nanocrystals for cell imaging

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Nano Research 2025年第1期18卷 675-683页

作者： xue li Yanan Guo Guoying Tan Qingyi liu Nan Song Yu Tang State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China

Lead halide perovskite nanocrystals(NCs)exhibit excellent optoelectronic performance and have drawn great interests in the fields of biological imaging and ***,the poor stability of CsPbX_(3)(X=Cl,Br,I)in water is still a challenge to hinder their practical *** this work,a facile strategy has been developed for aqueous synthesis of CsPbX_(3) nanocrystals,in which L-glutamic acid(LGlu)has been used to replace oleic acid in the synthetic *** from the synergic effects of L-Glu and oleylamine(OAm),CsPbBr_(3)nanocrystals(L-Glu/OAm-CsPbBr_(3)NCs)with high water stability have been directly prepared under a mild condition at room temperature in water,facilitated by the process of crystal phase transformation from Cs_(4)PbBr_(6) to CsPbBr_(3).L-Glu/OAm-CsPbBr_(3)NCs exhibit a high quantum yield of 85%and a narrow full width at half maximum of 16 nm,demonstrating their efficient luminescence in ***,L-Glu on the surface have contributed greatly to an acidic environment and passivation of surface defects,improving the water stability and dispersibility of CsPbBr_(3)***,L-Glu/OAm-CsPbBr_(3)NCs exhibit great biocompatibility due to the presence of L-Glu,resulting in their good performance for HeLa cell ***,we propose a facile and effective method to prepare CsPbBr_(3)nanocrystals with excellent water stability by using L-Glu and OAm as cooperated ligands and expand their application in cell imaging.

关键词： aqueous synthesis cell imaging lead halide perovskite nanocrystals L-glutamic acid phase transformation

Study of the material removal mechanism of glass-ceramics based on consecutive incremental loading in ductile-regime grinding

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Nanotechnology and Precision Engineering 2020年第2期3卷 88-95页

作者： xue li State Key Laboratory of Precision Measuring Technology&Instruments Tianjin UniversityTianjin 300072China

Glass-ceramics have many excellent properties and are widely used in various fields. During the grinding process,the workpiece surface is typically subject to material removal by grit of incremental heights, which has rarely been the focus of research. As such, it is necessary to study the material removal mechanism of glass-ceramics under consecutive incremental loading, which more closely reflects the actual grinding process. In this paper,to analyze the plastic deformation and residual stress of lithium aluminosilicate(LAS) glass-ceramics, a finite element model is established based on the Drucker–Prager yield criterion for ductile regimes. A nano-scratch test was also conducted and the test results show that both the residual depth and residual stress increase with an increase in the number of increments, and that consecutive incremental loading promotes the plastic deformation of glass-ceramics and increases the residual stress of the material in the ductile-regime process. These findings provide guidance for achieving higher dimensional accuracy in the actual grinding of glass-ceramics parts.

关键词： Grinding Glass-ceramics Scratch tests Material removal mechanism Consecutive incremental loading

Investigation and measurement of old building response to the overlapped shield tunnel of multiple schemes in the sandy cobble stratum

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Underground Space 2024年第2期15卷 260-274页

作者： xue li Aopeng Geng School of Geoscience and Technology Southwest Petroleum UniversityChengduSichuan 610500China China Railway Construction Bridge Engineering Bureau Group Co. Ltd.Tianjin 300300China

Ground movements due to tunneling are becoming increasingly critical as buildings are located around construction *** study proposes a new combined reinforcement method using a foundation grouting oblique pipe *** former improves the bearing capacity of the subsoil,and the latter blocks the transmission of soil deformation,which weakens the influence of construction during overlapped tunnel *** on this new method,a case study of the shield tunneling response to an old building in line 6 of China’s Chengdu Metro is ***,three-dimensional numerical models without reinforcement,traditional foundation grouting reinforcement,and the new combined reinforcement schemes were *** numerical simulation performance was verified using a set of field instrumentation data,which demonstrated that the old building response to the overlapped tunnels was under control,and the maximum deformation,angular distortion,and principal tensile strain of the building were 5.25 mm,5.1010–6 rad/m,and 0.0081%,*** with the traditional reinforcement scheme,the deformation,angular distortion,and principal tensile strain in the combined reinforcement scheme were reduced by 54.78%,71.02%,and 70.22%,*** results have important implications for the design and construction of shield tunnels and their response to old buildings.

关键词： Overlapped tunnels Reinforcement schemes Under-crossing Old building Numerical simulation

Greedy Optimization for K-Means-Based Consensus Clustering

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Tsinghua Science and Technology 2018年第2期23卷 184-194页

作者： xue li Hongfu liu School of Economics and Management Tsinghua University Beijing 100084 China. Department of Electrical and Computer Engineering Northeastern University Boston MI 02115 USA.

Consensus clustering aims to fuse several existing basic partitions into an integrated one; this has been widely recognized as a promising tool for multi-source and heterogeneous data clustering. Owing to robust and high-quality performance over traditional clustering methods, consensus clustering attracts much attention, and much efforts have been devoted to develop this field. In the literature, the K-means-based Consensus Clustering(KCC) transforms the consensus clustering problem into a classical K-means clustering with theoretical supports and shows the advantages over the state-of-the-art methods. Although KCC inherits the merits from K-means,it suffers from the initialization sensitivity. Moreover, the current consensus clustering framework separates the basic partition generation and fusion into two disconnected parts. To solve the above two challenges, a novel clustering algorithm, named Greedy optimization of K-means-based Consensus Clustering(GKCC) is *** by the well-known greedy K-means that aims to solve the sensitivity of K-means initialization, GKCC seamlessly combines greedy K-means and KCC together, achieves the merits inherited by GKCC and overcomes the drawbacks of the precursors. Moreover, a 59-sampling strategy is conducted to provide high-quality basic partitions and accelerate the algorithmic speed. Extensive experiments on 36 benchmark datasets demonstrate the significant advantages of GKCC over KCC and KCC++ in terms of the objective function values and standard deviations and external cluster validity.

关键词： K-means consensus clustering initialization greedy optimization

Finite element analysis of dynamic stability of bearingless rotor

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航空动力学报 2014年第5期29卷 1112-1121页

作者： WEI li-jun li Shu li xue-chang School of Aeronautic Science and Engineering Beijing University of Aeronautics and Astronautics

Dynamic stability equations of bearingless rotor blades were investigated using a simplified *** aerodynamic loads of blades were evaluated using two-dimensional airfoil *** equations were obtained by linearization of the perturbation.A normal-mode approach was used to transform the equations expressed by nodal degrees of freedom into equations expressed by modal degrees of freedom,which can reduce the dimension of the *** stability results of rotor blades were presented using eigenvalue *** shape function matrix was obtained using spline interpolation,which simplified the analysis and made assembly of the inertial matrix,damping matrix,and stiffness matrix a simple mathematical *** results indicate that the method is efficient and greatly simplifies the analysis.

关键词：无轴承转子动态稳定性有限元法样条插值特征值分析

Controllability of Nonlinear Discrete Systems with Degeneracy

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 293-305页

作者： Yue LYU xue-li TAN xue YANG Yong li School of Mathematics Jilin UniversityChangchun130012China Center for Mathematics and Interdisciplinary Sciences Northeast Normal UniversityChangchun 130024China

This paper concerns the controllability of autonomous and nonautonomous nonlinear discrete systems,in which linear parts might admit certain *** introducing Fredholm operators and coincidence degree theory,sufficient conditions for nonlinear discrete systems to be controllable are *** addition,applications are given to illustrate main results.

关键词： nonlinear discrete systems controllability degeneracy Fredholm operators coincidence degree theory

Density Functional Theory Investigation on the Reaction Mechanisms of Ti(^3F)with CH2Cl2 and CHCl3 to CH2=TiCl2 and HC÷TiCl3

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Chinese Journal of Structural Chemistry 2016年第2期35卷 193-198页

作者： CHENG xue-li (School of Chemistry and Chemical Engineering Taishan UniversityTai'anShandong 271021China

The reaction mechanisms of Ti（~3F）＋ CH2C12→CH2=TiCl2 and Ti（~3F）＋ CHC13→HC÷TiCl3 were investigated with Gaussian 03 program package at the B3PW91/6-311＋＋G（d,p）*** computational results revealed that：1） Both reaction systems are initiated by Ti（~3F） atom attacking the C atom of CH2C12 and CHCl3 to activate a C-Cl bond;2） Both reaction systems were carried out via triplet reaction channels;3） CH2=TiCl2 has singlet and triplet isomers,and the singlet one is more stable;4） The HOMO of CH2=TiCl2（S） illustrates a π-bonding interaction between C and Ti;5） Only singlet HC÷TiCl3 was located,and the Mulliken atomic spin densities show that the two single electrons are mostly on the C atom.

关键词： B3PW91 reaction mechanism Ti(~3F) CH2=TiCl2 HOTiCl3

Rheological properties of a multiscale granular system during mixing of cemented paste backfill:A review

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International Journal of Minerals,Metallurgy and Materials 2023年第8期30卷 1444-1454页

作者： Cuiping li xue li Zhu’en Ruan Key Laboratory of the Ministry of Education of China for High-efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing100083China Shunde Innovation School of University of Science and Technology Beijing Foshan528399China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China

The technology of cemented paste backfill(CPB)is an effective method for green *** CPB,mixing is a vital process aiming to prepare a paste that meets the non-stratification,non-segregation,and non-bleeding *** a multiscale granular system,homogenization is one of the challenges in the paste-mixing *** to the high shearing,high concentration,and multiscale characteristics,paste exhibits complex rheological properties in the mixing *** overview of the mesomechanics and structural evolution is presented in this *** effects of various influencing factors on the paste's rheological properties were investigated,and the rheological models of the paste were outlined from the macroscopic and mesoscopic *** results show that the mechanical effects and structural evolution are the fundamental factors affecting the rheological properties of the *** problems and future development trends are presented to change the practice where the CPB process comes first and the theory lags.

关键词： cemented paste backfill rheology mixing process mesomechanics structural evolution

Binomial Proportion Estimation in Longitudinal Data with Non-ignorable Non-response

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Acta Mathematicae Applicatae Sinica 2013年第3期29卷 623-630页

作者： xue-li WANG School of Science Beijing University of Posts and Telecommunications

Non-random missing data poses serious problems in longitudinal studies. The binomial distribution parameter becomes to be unidentifiable without any other auxiliary information or assumption when it suffers from ignorable missing data. Existing methods are mostly based on the log-linear regression model. In this article, a model is proposed for longitudinal data with non-ignorable non-response. It is considered to use the pre-test baseline data to improve the identifiability of the post-test parameter. Furthermore, we derive the identified estimation （IE）, the maximum likelihood estimation （MLE） and its associated variance for the post-test parameter. The simulation study based on the model of this paper shows that the proposed approach gives promising results.

关键词： Binomial proportion information matrix identifiability non-ignorable non-response variance estimation