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Science China Mathematics 2016年第3期59卷 589-608页

作者： dong Xiao Jing he Yin Nian School of Mathematics and Statistics Xi'an Jiaotong University

Based on the finite element method(FEM), some iterative methods related to different Reynolds numbers are designed and analyzed for solving the 2D/3D stationary incompressible magnetohydrodynamics(MHD) numerically. Two-level finite element iterative methods, consisting of the classical m-iteration methods on a coarse grid and corrections on a fine grid, are designed to solve the system at low Reynolds numbers under the strong uniqueness condition. One-level Oseen-type iterative method is investigated on a fine mesh at high Reynolds numbers under the weak uniqueness condition. Furthermore, the uniform stability and convergence of these methods with respect to equation parameters R_e, R_m, S_c, mesh sizes h, H and iterative step m are provided. Finally, the efficiency of the proposed methods is confirmed by numerical investigations.

关键词： stationary incompressible magnetohydrodynamics finite element method iterative method twolevel algorithms

Frontsand strong currents of the upper southeast Indian Ocean

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Acta Oceanologica Sinica 2006年第2期25卷 1-24页

作者： he Zhigang dong Zhaoqian YUAN Xiaojun Department of Oceanography Xiamen University Xiamen 361005 China Polar Research Institute of China Shanghai 200136 China Lamont-Doherty Earth Observatory Columbia University Palisades New York NY 10964-800 USA

Hydrographic data, ADCP velocity and sea level anomaly derived from the satellite altimeter have been jointly analyzed in the southeast lndian Ocean. Results show the locations and orientations of the major oceanic fronts as well as the characteristics of the currents within these fronts in the area. Double subtropical fronts are observed in the section along 120°E, which conflicts with the frontal structure frequently observed before the North Subtropical Front （NSTF） and South Subtropical Front （SSTF） merge into a single STF between 110°-115°E. The Subantarctic Front （SAF）, influenced by the out-of-phase double eddies, runs across 48°S three times between 120° and 127°E. The surface current within the SAF is strengthened up to 105.4 cm/s by the geostrophic effect of these eddies. Furthermore eddies may cause the strong current to split up into two branches within the SAF. The SAF and the primary polar front （PFI） can be identified individually in the ADCP data with a separation distance of about 0.3° at latitude between 140° and 145°E, although they cannot be identified separately in the low-resolution hydrographic data. The different thcrmohaline characteristics of Circumpolar Deep Water （CDW） and Modified Circumpolar Deep Water （MCDW） result in the formation of Southern Antarctic Circumpolar Current Front （SACCF） in the southeast Indian Ocean. It consistently turns northward along the east flank of the Kerguclen Plateau after it runs through the Princess Elizabeth Trough and turns southward sharply north of 60°S with a little seasonal variations. It is shown that the locations and orientations of the SAK the primary PF and SACCF in the ACC of the southeast Indian Ocean can be identified more precisely by the current distribution derived from ADCP data than by hydrographic data, because these fronts are usually accompanied by strong currents. However, the locations and orientations of the STF and the secondary PF are more difficult to be identified through cur

关键词： southeast Indian Ocean front jet

Fatigue Life Evaluation Method for Foundry Crane Metal Structure Considering Load Dynamic Response and Crack Closure Effect

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Computer Modeling in Engineering & Sciences 2020年第2期122卷 525-553页

作者： Qing dong Bin he Gening Xu School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuanChina.

To compensate for the shortcomings of quasi-static law in anti-fatigue analysis of foundry crane metal structures,the fatigue life evaluation method of foundry crane metal structure considering load dynamic response and crack closure effect is *** line with the theory of mechanical vibration,a dynamic model of crane structure during the working cycle is constructed,and dynamic coefficients under diverse actions are *** models of the internal force dynamic change process of dangerous cross-sections and a simulation model of first principal stress-time history are established by using the steel structure design criteria,which is utilised to extract the change of first principal stress of danger points over ***,the double-parameter stress spectrum is obtained by the rain flow counting *** fatigue life calculation formula is corrected by introducing a crack closure parameter that can be calculated by the stress ratio and the effective stress *** the finite element model imported into ***,crack propagation analysis is performed by the growth method in the fatigue integration module *** the metal structure of a 100/40t-28.5m foundry crane with track offset as an example,the accuracy of calculation results and the feasibility and applicability of the proposed method are verified by theoretical calculation and finite element simulation,which provide a theoretical basis for improvement of the fatigue resistance design of foundry cranes.

关键词： Metal structure of foundry crane load dynamic effect crack closure effect crack propagation fatigue life.

A nonsmooth IMC method for mechanical systems with backlash

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控制理论与应用（英文版） 2013年第4期11卷 600-607页

作者： Ruili dong Yonghong TAN David he College of Mechanical and Electronic Technology Shanghai Normal University Department of Mechanical and Industrial Engineering University of Illinois at Chicago

This paper proposes a discrete-time nonsmooth internal model control （NSIMC） approach for mechanical transmission systems described by so-called sandwich system with backlash. In this method, a dynamic compensator is introduced to compensate for the effect of the input linear subsystem. Thus, the sandwich systems with backlash can be simplified as a pseudo-Hammerstein system with backlash. The corresponding NSIMC strategy is designed to control this system. The design procedure of the controller is presented based on the analysis on the robust stability by considering the model errors involved with the effect of backlash as well as the compensated error of the input linear subsystem. Moreover, as the model is switched among the different operating zones, the robust filters are proposed to guarantee the robust stability and satisfactory control performance of the system.

关键词： Backlash Internal model control Sandwich system Nonsmooth nonlinear systems

Neutrophil-mimetic hybrid liposome with ROS cascade amplification for synergistic ferroptosis-photodynamic therapy of breast cancer

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Nano Research 2024年第11期17卷 9932-9941页

作者： Jiaxin Li Jiaxin Li Jiao he Xuan he dong Chen Ziyan dong Lin Xiong Wenjing Bai Man Li Rong Guo Qin he Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology Med-X Center for Materials West China School of Pharmacy Sichuan University Chengdu 610041 China Department of Biochemistry and Molecular Biology West China School of Basic Medical Sciences and Forensic Medicine Sichuan University Chengdu 610041 China

Photodynamic therapy (PDT) and ferroptosis therapy have received extensive attention in breast cancer treatment. PDT induced apoptosis of tumor cells by producing a large amount of reactive oxygen species (ROS) under laser irradiation. Differently, ferroptosis therapy exerts its antitumor effect by inducing excessive accumulation of lipid peroxides on tumor cell membranes. Based on that, ROS produced by PDT may promote ferroptosis in tumor cells, and ferroptosis therapy is expected eliminate apoptosis-resistant tumor cells. Therefore, a synergistic ferroptosis-photodynamic therapy will be more effective and more potential in breast cancer treatment. Considering PDT has the characteristic of producing ROS, and neutrophil has a natural tendency to ROS, a neutrophil-mimetic hybrid liposome (CR-NML) was designed for co-delivery of the photosensitizer Ce6 and the ferroptosis inducer RSL3. CR-NML targeted tumor through the ROS tendency of neutrophil and the enhanced permeability and retention (EPR) effect of liposome, then induced both apoptosis and ferroptosis in tumor cells, which increased ROS level and finally realized ROS cascade amplification. The synergistic ferroptosis-photodynamic therapy demonstrated significant therapeutic efficacy in 4T1 tumor bearing mice, which provided a promising strategy for breast cancer treatment.

关键词： neutrophil-mimetic hybrid liposome reactive oxygen species(ROS)cascade amplification photodynamic therapy ferroptosis therapy breast cancer

A Comparison of Conventional and Shear-Rate Dependent Mohr-Coulomb Models for Simulating Landslides

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Journal of Mountain Science 2014年第6期11卷 1478-1490页

作者： LIANG dong-fang he Xu-zhen MOE Key Laboratory of Hydrodynamics Shanghai Jiao Tong University Department of Engineering University of Cambridge Trumpington StreetCambridge CB2 1PZ UK

Landslides may cause many fatalities and heavy economic losses,so it is vital to understand their mechanics so as to take appropriate measures to mitigate their ***,the loose soil behaves like frictional material in most circumstances,so Mohr-Coulomb type equations are often used to describe their ***,these models generally do not consider the influence of the shearrate on the Mohr-Coulomb friction angle,so the shear-rate dependence effect on the soil flow and landslide runout is not well *** paper reports on an application of the incompressible Smoothed Particle Hydrodynamics(SPH) method to the dynamics of dry granular *** traditional model with a constant friction angle is compared with the modified Mohr-Coulomb model with a variable friction angle related to the *** is found that the shear-rate dependence effect is negligible for shallow granular flows along mild *** steeper slopes of the ground and larger aspect ratios of the initial soil column,the rate-dependence effect becomes more important.

关键词： Landslides Granular flows MohrCoulomb model Smoothed Particle Hydrodynamics

Rapid heating thermal shock study of ultra high temperature ceramics using an in situ testing method

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Journal of Advanced Ceramics 2017年第4期6卷 279-287页

作者： Rujie he Zhaoliang QU dong LIANG Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China

In this paper,the rapid cooling thermal shock behaviors of ZrB_(2)-SiC ceramics were measured using traditional water quenching method,and the rapid heating thermal shock behaviors of ZrB_(2)-SiC ceramics were investigated using a novel in situ testing *** measured critical thermal shock temperature difference for rapid cooling thermal shock was 373.6℃;however,the critical thermal shock temperature difference for rapid heating thermal shock of ZrB_(2)-SiC ceramics was measured to be as high as 1497.2℃.The thermal stress distribution states after rapid cooling thermal shock and rapid heating thermal shock testing were analyzed using finite element analysis(FEA)*** FEA results showed that there is a tensile stress existed on the surface for rapid cooling thermal shock,whereas there is a compressive stress existed on the surface for rapid heating thermal *** difference of thermal stress distribution resulted in the difference of the critical temperature difference for rapid cooling thermal shock and rapid heating thermal shock.

关键词： ultra high temperature ceramics(UHTCs) thermal shock behavior thermal stress finite element analysis(FEA)

On the GF(p) Linear Complexity of Hall's Sextic Sequences and Some Cyclotomic-Set-Based Sequences

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Chinese Annals of Mathematics,Series B 2016年第4期37卷 515-522页

作者： Xianmang he Liqin HU dong LI School of Information Science and Technology Ningbo University School of Computer Science and Technology Fudan University Department of Mathematics Nanjing University of Aeronautics and Astronautics Information Center National Natural Science Foundation of China

Klapper(1994) showed that there exists a class of geometric sequences with the maximal possible linear complexity when considered as sequences over GF(2), but these sequences have very low linear complexities when considered as sequences over GF(p)(p is an odd prime). This linear complexity of a binary sequence when considered as a sequence over GF(p) is called GF(p) complexity. This indicates that the binary sequences with high GF(2) linear complexities are inadequate for security in the practical application, while,their GF(p) linear complexities are also equally important, even when the only concern is with attacks using the Berlekamp-Massey algorithm [Massey, J. L., Shift-register synthesis and bch decoding, IEEE Transactions on Information Theory, 15(1), 1969, 122–127]. From this perspective, in this paper the authors study the GF(p) linear complexity of Hall's sextic residue sequences and some known cyclotomic-set-based sequences.

关键词： Linear complexity Hall's sextic residues sequence Cyclotomic set

System Integration of Terrestrial Mobile Communication and Satellite Communication——The Trends, Challenges and Key Technologies in B5G and 6G

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China Communications 2020年第12期17卷 156-171页

作者： Shanzhi Chen shaohui Sun Shaoli Kang State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunication TechnologyBeijing 100191China

Mobile communication standards have been developed into a new era of B5G and *** recent years,low earth orbit(LEO)satellites and space Internet have become hot *** integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in *** paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within *** on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.

关键词： satellite communication terrestrial mobile communication system integration B5G 6G space internet

Lignite-Based Hierarchical Porous C/SiO_(x)Composites as High-Performance Anode for Potassium-Ion Batteries

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Energy & Environmental Materials 2024年第4期7卷 107-117页

作者： Zexu Yang Shouwang Zhao Rongji Jiao Gengyu Hao Yunying Liu Wenxiu he Jingwei Chen Guixiao Jia Jinlong Cui shaohui Li School of Chemistry and Chemical Engineering Aerogel Functional Nanomaterials LaboratoryInner Mongolia University of Science&TechnologyBaotou 014010China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Silicon oxide(SiO_(x),0heoretical capacity,suitable electrochemical potential,and earth ***,it... 详细信息

Silicon oxide(SiO_(x),0heoretical capacity,suitable electrochemical potential,and earth ***,it is intrinsically poor electronic conductivity and excessive volume expansion during potassiation/depotassiation process hinder its application in potassium-ion ***,we reported a hierarchical porous C/SiO_(x)potassium-ion batteries anode using lignite as raw material via a one-step carbonization and activation *** amorphous C skeleton around SiO_(x)particles can effectively buffer the volume expansion,and improve the ionic/electronic conductivity and structural integrity,achieving outstanding rate capability and *** expected,the obtained C/SiO_(x)composite delivers a superb specific capacity of 370 mAh g^(-1)at 0.1 A g^(-1)after 100 cycles as well as a highly reversible capacity of 208 mAh g^(-1)after 1200 cycles at 1.0 A g^(-1).Moreover,the potassium ion storage mechanism of C/SiO_(x)electrodes was investigated by ex-situ X-ray diffraction and transmission electron microscopy,revealing the formation of reversible products of K_(6.8)Si_(45.3)and K_(4)SiO_(4),accompanied by generation of irreversible K2O after the first *** work sheds light on designing low-cost Si-based anode materials for high-performance potassium-ion batteries and beyond.

关键词： anode hierarchical porous C/SiO_(x) K_(4)SiO_(4) lignite potassium-ion batteries