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经济研究导刊 2011年第23期 275-276页

作者：雷忠仁黑龙江省商业职工大学哈尔滨150018

讨论了"网络平台"下如何把网络知识和网络应用技能渗透到整个计算机基础教学过程中,总结和归纳了进一步以提高应用能力为目标的非计算机专业计算机基础教学的方法和经验。

关键词：网络计算机教学

Influence of Sedimentation on Crystallization of Charged Colloidal Particles

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Chinese Journal of Chemical Physics 2012年第3期25卷 318-324,374页

作者： Xuan Du Sheng-hua Xu Zhi-wei Sun lei Liu Key Laboratory of Microgravity Institute oF Mechanics Chinese Academy of Sciences Beijing 100190China National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beiijing100190 China

The method of density matching between the solid and liquid phases is often adopted to effectively eliminate the effect of sedimentation of suspensions on dynamic behavior of a colloidal system. Experiments on crystallization of charged colloidal microspheres with di- ameter of 98 nm dispersed in density-matched and -unmatched media （mixtures of H20 and D20 in proper proportion） are compared to examine the influence of sedimentation. Reflection spectra of colloidal suspensions were used to monitor the crystallization process. Results showed that the crystal size of the density-unmatched （namely, in the presence of sedimentation） sample grew faster than that of the density-matched （in the absence of sedi- mentation） case at the initial stage of the crystallization, and then the latter overtook and outstripped the former. To explain these observations, we assume that in the settling of crystals sedimentation facilitates result in more particles getting into the crystal structures. However, as the crystals increase to varying sizes, the settling velocities become large and hydrodynamic friction strips off some particles from the delicate crystal structures. Overall, the sedimentation appears to accelerate the crystal size growth initially and then retard the growth. In addition, the crystal structures formed under microgravity were more closely packed than that in normal gravity.

关键词： Colloidal crystal Density matching Sedimentation Reflection spectrum

Accurate RGB-D SLAM in dynamic environments based on dynamic visual feature removal

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Science China(Information Sciences) 2022年第10期65卷 256-269页

作者： Chenxin LIU Jiahu QIN Shuai WANG lei YU Yaonan WANG Department of Automation University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center College of Electrical and Information Engineering Hunan University National Engineering Research Center of Robot Visual Perception and Control Technology Hunan University

Visual localization is considered an essential capability in robotics and has attracted increasing interest for the past few years. However, most proposed visual localization systems assume that the surrounding environment is static, which is difficult to maintain in real-world scenarios due to the presence of moving objects. In this paper, we present DFR-SLAM, a real-time and accurate RGB-D SLAM based on ORB-SLAM2 that achieves satisfactory performance in a variety of challenging dynamic scenarios. At the core of our system lies a motion consensus filtering algorithm estimating the initial camera pose and a graph-cut optimization framework combining long-term observations, prior information, and spatial coherence to jointly distinguish dynamic and static visual features. Other systems for dynamic environments detect dynamic components by using the information from short time-span frames, whereas our system uses observations from a long period of keyframes. We evaluate our system using dynamic sequences from the public TUM dataset, and the evaluation demonstrates that the proposed system outperforms the original ORB-SLAM2 system significantly. In addition, our system provides competitive localization accuracy with satisfactory real-time performance compared to closely related SLAM systems designed to adapt to dynamic environments.

关键词： SLAM dynamic environments indoor localization graph-cut robot navigation

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Blood-based Alzheimer’s disease diagnosis using fluorescent peptide nanoparticle arrays

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Chinese Chemical Letters 2022年第4期33卷 1946-1950页

作者： Leming Sun Yang lei Yuerong Wang Dingchang Liu Key Laboratory of Space Bioscience and Biotechnology School of Life SciencesNorthwestern Polytechnical UniversityXi’an 710072China

There is a critical need to diagnose and monitor the progression of Alzheimer’s disease(AD) using bloodbased biomarkers. At present, it is believed that tau biomarkers can be utilized to reliably detect *** techniques are highly sought after for AD diagnosis and progression monitoring. For this purpose, we developed a fluorescent peptide nanoparticles(f-PNPs) arrays that is capable of detecting multiple signals simultaneously. The concentration, aggregation stages, and Young’s modulus of tau biomarkers could be analyzed by monitoring the changes of multimodal fluorescence intensity, nano-morphological,and nano-mechanical properties of the f-PNPs arrays. Experimental results indicated that, compared to healthy human, the concentration, Young’s modulus, and aggregation levels of tau proteins in blood samples of clinically diagnosed AD patients increased continuously with the increase of disease severity. The minimally invasive and multimodal characterization techniques showed high signal-to-noise ratio for AD diagnosis.

关键词： Self-assembly Alzheimer’s disease Fluorescent peptide nanoparticles Blood-based diagnosis Tau proteins Multimodal

Red soil for sediment capping to control the internal nutrient release under flow conditions

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Frontiers of Environmental Science & Engineering 2016年第6期10卷 63-71页

作者： lei Xia Guo Liu Chunmei Chen Meiyan Wen Yangyang Gao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Sichuan Provincial Environmental Protection Key Laboratory of Groundwater Pollution Prevention and Resource Security Chengdu University of Technology Chengdu 610059 China

Nitrogen （N） and phosphorus （P） released from the sediment to the surface water is a major source of water quality impairment. Therefore, inhibiting sediment nutrient release seems necessary. In this study, red soil （RS） was employed to control the nutrients released from a black-odorous river sediment under flow conditions. The N and P that were released were effectively controlled by RS capping. Continuous-flow incubations showed that the reduction efficiencies of total N （TN）, ammonium （NH4＋-N）, total P （TP） and soluble reactive P （SRP） of the overlying water by RS capping were 77%, 63%, 77% and 92%, respectively, and nitrification and denitrification occurred concurrently in the RS system. An increase in the water velocity coincided with a decrease in the nutrient release rate as a result of intensive water aeration.

关键词： Sediment Red soil capping Flow conditions Nitrogen Phosphorus

Light-induced phosphine-catalyzed asymmetric functionalization of benzylic C–H bonds

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Science China Chemistry 2023年第1期66卷 127-132页

作者： Jiami Guo Zi-An Shen Xueting Zhou lei Dai Yixin Lu Joint School of National University of Singapore and Tianjin University International Campus of Tianjin University Binhai New CityFuzhou 350207China Department of Chemistry National University of SingaporeSingapore 117543Singapore

Despite rapid development in the past two decades,there are still some unsolved synthetic challenges in the field of phosphine *** this report,through photo-induced activation of ortho-alkyl aromatic ketones,we achieved highly enantioselective functionalization of substrates bearing a benzylic C–H *** the presence of amino acid-derived bifunctional phosphine catalysts,a range of benzylic allylation products were obtained in good yields and with excellent *** strategy disclosed herein offers new insight into the activation and functionalization of pronucleophiles containing less acidic C–H bonds in the domain of phosphine catalysis and beyond.

关键词： phosphine catalysis nucleophilc catalysis enantioselective benzylic C-H bonds

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3372-3375页

作者： lei Gao Qiang Lin Department of Medical Imaging North China Petroleum Bureau General HospitalHebei Medical UniversityRenqiu 062552Hebei ProvinceChina Department of Oncology North China Petroleum Bureau General HospitalHebei Medical UniversityRenqiu 062552Hebei ProvinceChina

Gastric cancer ranks as the sixth most prevalent cancer *** recent research within the realm of gastric cancer treatment,the identification and application of immune-related genetic features have emerged as groundbreaking *** study by Ma et al,which developed a prognostic model based on 10 genes,categorizes patients into high and low-risk groups to predict their responsiveness to immune checkpoint inhibitor *** research underscores the potential of immune-related genes as biomarkers for personalized treatment,offering insights into tumor mutation burden and immune phenotype *** advocate for further validation,understanding of biological mechanisms,and integration of diverse datasets to enhance the model's predictive accuracy and clinical application,marking a significant step towards personalized and precise treatment for gastric cancer.

关键词： Gastric cancer Personalized treatment Immune-related genes Immunotherapy Genomics

A novel multi-fidelity coupled simulation method for flow systems

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Chinese Journal of Aeronautics 2013年第4期26卷 868-875页

作者： Wang Peng Zheng Yun Zou Zhengping Qi lei Zhou Zhixiang National Key Laboratory of Science & Technology on Aero-Engine Aero-thermodynamics School of Energy and Power Engineering Beihang University Aeroengine Numerical Simulation Research Center School of Energy and Power Engineering Beihang University Chinese Aviation Powerplant Research Institute

For the numerical simulation of flow systems with various complex components, the traditional one-dimensional （1D） network method has its comparative advantage in time consuming and the CFD method has its absolute advantage in the detailed flow capturing. The proper coupling of the advantages of different dimensional methods can strike balance well between time cost and accuracy and then significantly decrease the whole design cycle for the flow systems in modern machines. A novel multi-fidelity coupled simulation method with numerical zooming is developed for flow systems. This method focuses on the integration of one-, two-and three-dimensional codes for various components. Coupled iterative process for the different dimensional simulation cycles of sub-systems is performed until the concerned flow variables of the whole system achieve convergence. Numerical zooming is employed to update boundary data of components with different dimen-sionalities. Based on this method, a highly automatic, multi-discipline computing environment with integrated zooming is developed. The numerical results of Y-Junction and the air system of a jet engine are presented to verify the solution method. They indicate that this type of multi-fidelity simulationmethod can greatly improve the prediction capability for the flow systems.

关键词： Complex flow system Coupling Jet engine Multi-fidelity Zooming

Determination of thermal expansion coefficients for unidirectional fiber-reinforced composites

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Chinese Journal of Aeronautics 2014年第5期27卷 1180-1187页

作者： Ran Zhiguo Yan Ying Li Jianfeng Qi zhongxing Yang lei School of Aeronautics Science and Engineering Beihang University

In the present work, the coefficients of thermal expansion（CTEs） of unidirectional（UD）fiber-reinforced composites are studied. First, an attempt is made to propose a model to predict both longitudinal and transverse CTEs of UD composites by means of thermo-elastic mechanics analysis. The proposed model is supposed to be a concentric cylinder with a transversely isotropic fiber embedded in an isotropic matrix, and it is subjected to a uniform temperature change. Then a concise and explicit formula is offered for each CTE. Finally, some finite element（FE） models are created by a finite element program MSC. Patran according to different material systems and fiber volume fractions. In addition, the available experimental data and results of other analytical solutions of CTEs are presented. Comparisons are made among the results of the cylinder model,the finite element method（FEM）, experiments, and other solutions, which show that the predicted CTEs by the new model are in good agreement with the experimental data. In particular, transverse CTEs generally offer better agreements than those predicted by most of other solutions.

关键词： Analytical solution Coefficient of thermal expansion Thermo-elastic Transversely isotropic Unidirectional composites

Nickel nanopore arrays as promising current collectors for constructing solid-state supercapacitors with ultrahigh rate performance

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Frontiers of Chemical Science and Engineering 2018年第3期12卷 339-345页

作者： Huaping Zhao Long Liu Yaoguo Fang Ranjith Vellacheri Yong lei Institute of Physics and IMN MacroNano Ilmenau University of Technology Ilmenau 98693 Germany

In this work, nickel nanopore arrays with a highly-oriented nanoporous structure inherited from por- ous alumina membranes were used as nanostructured current collectors for constructing ultrahigh rate solid-state supercapacitors. A thin layer of poly（3,4-ethylenediox- ythiophene）（PEDOT） as electroactive materials was conformally coated onto nickel nanopores to form heterostructured electrodes. The as-prepared electrodes have a large specific surface area to ensure a high capacity, and the highly-oriented nanoporous structure of nickel nanopores reduces the ion transport resistance, allowing the ions in the solid-state electrolytes to quickly access the PEDOT surface during the fast charge-discharge process. As a result, the assembled solid-state supercapacitor in a symmetric configuration exhibits an ideal capacitive behavior and a superior rate capability even at an ultrahigh scan rate of 50 V· s^-1.

关键词： supercapacitor ultrahigh rate metallic nanopore arrays current collectors PEDOT