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Porous Organic Cage‑Based Quasi‑Solid‑State Electrolyte with Cavity‑Induced Anion‑Trapping Effect for Long‑Life Lithium Metal Batteries

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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang Li Wen‑Xia su Jia‑Min Hu Hanqin Zou Zhixuan wu Zhiqin Ruan Yue‑Peng Cai Kang Li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of Hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery

Convergence analysis of a nonlinear Lagrange algorithm for general nonlinear constrained optimization problems

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Applied Mathematics(A Journal of Chinese Universities) 2014年第3期29卷 352-366页

作者： HE su-xiang wu Li-xun School of Science Wuhan University of Technology

The convergence analysis of a nonlinear Lagrange algorithm for solving nonlinear constrained optimization problems with both inequality and equality constraints is explored in detail. The estimates for the derivatives of the multiplier mapping and the solution mapping of the proposed algorithm are discussed via the technique of the singular value decomposition of matrix. Based on the estimates, the local convergence results and the rate of convergence of the algorithm are presented when the penalty parameter is less than a threshold under a set of suitable conditions on problem functions. Furthermore, the condition number of the Hessian of the nonlinear Lagrange function with respect to the decision variables is analyzed, which is closely related to efficiency of the algorithm. Finally, the preliminary numericM results for several typical test problems are reported.

关键词： nonlinear Lagrange algorithm general nonlinear constrained optimization problem solutionmapping multiplier mapping condition number.

Changes in Mortality Rates of Major Chronic Diseases Among Populations Aged Over 60 Years and Their Contributions to Life Expectancy Increase-China,2005-2020

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China CDC weekly 2022年第39期4卷 866-870,I0002页

作者： Yue Cai xiang Cui Binbin su Shiyong wu Center for Health Statistics and Information National Health CommissionBeijingChina Department of Epidemiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Key Laboratory of Cardiovascular Epidemiology Chinese Academy of Medical SciencesBeijingChina School of Population Medicine and Public Health Chinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina

summary What is already known about this topic?The impacts of population aging have appeared in China,leading to a marked shift in the major contributors to life *** improvements are now mainly promoted by reductions in mortality rates of the *** is added by this report?This study systematically evaluates both changes in mortality rates of major chronic diseases among populations aged over 60 years as well as their contributions to life expectancy increases in China,from 2005 to *** are the implications for public health practice?The results of this study demonstrate that more attention should be paid to health conditions of the elderly,especially for the prevention and control of major chronic diseases.

关键词： prevention Population Major

Broken-up spectra of the loop-top hard X-ray source during a solar limb flare

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Research in Astronomy and Astrophysics 2019年第12期19卷 207-216页

作者： Hao Ning Yao Chen Jeongwoo Lee Zhao wu Yang su xiang-Liang Kong Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment and Institute of Space SciencesShandong UniversityWeihai 264209China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008China

Solar hard X-rays(HXRs) appear in the form of either footpoint sources or coronal sources. Each individual source provides its own critical information on acceleration of nonthermal electrons and plasma heating. Earlier studies found that the HXR emission in some events manifests a broken-up power-law spectrum, with the break energy around a few hundred keV based on spatially-integrated spectral analysis,and it does not distinguish the contributions from individual sources. In this paper, we report on the brokenup spectra of a coronal source studied using HXR data recorded by Reuven Ramaty High Energy Solar Spectroscopic Imager(RHESSI) during the SOL2017–09–10 T16:06(GOES class X8.2) flare. The flare occurred behind the western limb and its footpoint sources were mostly occulted by the disk. We could clearly identify such broken-up spectra pertaining solely to the coronal source during the flare peak time and after. Since a significant pileup effect on the RHESSI spectra is expected for this intense solar flare, we have selected the pileup correction factor, p = 2. In this case, we found the resulting RHESSI temperature(~30MK) to be similar to the GOES soft X-ray temperature and break energies of 45–60 keV. Above the break energy, the spectrum hardens with time from spectral index of 3.4 to 2.7, and the difference in spectral indices below and above the break energy increases from 1.5 to 5 with time. However, we note that when p = 2 is assumed, a single power-law fitting is also possible with the RHESSI temperature higher than the GOES temperature by ~10MK. Possible scenarios for the broken-up spectra of the loop-top HXR source are briefly discussed.

关键词： acceleration of particles sun:corona sun:flares sun:UV radiation sun:X-rays gamma rays

surface Patterning of Self-healing P(MMA/nBA)Copolymer for Dynamic Control Cell Behaviors

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Chinese Journal of Polymer Science 2020年第7期38卷 696-703,I0005页

作者： su-su Liu Ze-Hong xiang Zhi-Fang Ma Xue-Wen wu Qiang Shi Shing-Chung Wong Jing-Hua Yin School of Chemical Engineering Xiangtan UniversityXiangtan 411105China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Mechanical Engineering University of AkronOhio 44323-3903USA

Cell behaviors are regulated by a dynamic and complex environment characterized by biophysical,mechanical and biochemical ***,most works regulate cell behaviors under static conditions or by external *** control cell adhesion and proliferation with a dynamic and mechanical environment,we pattern the surface on self-healing copolymer P(MMA/nBA).The copolymer P(MMA/nBA)with the composition of 48/52(MMA/nBA)recovers nearly 100%of its original tensile strains after 86 h of recovery from *** physical patterns on P(MMA/nBA)film are obtained over large areas and the size of the hole and the width of connecting bar are in line with the copper grid *** patterned surface tends to be fiat after 12 h with almost 75%-80%*** with cell incubation on polystyrene fiat and patterned surface of P(MMA/nBA)film without self-healing capability,the number and morphology of cells are well manipulated on the patterned surface of self-healing P(MMA/nBA)*** approach provides a convenient method for dynamically regulating the cell behaviors on the surface of self-healing materials without chemical or biological modifications.

关键词： surface pattern Self-healing Cell behavior Dynamic

Microstructural characterization and oxidation resistance of multicomponent equiatomic CoCrCuFeNi–TiO high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1286-1293页

作者： Qing-dong Qin Jin-bo Qu Yong-e Hu Yu-jiao wu xiang-dong su Key Laboratory of Light Metal Materials Processing Technology of Guizhou Province Guizhou Institute of TechnologyGuiyang 550003China Department of Materials&Metallurgy Engineering Guizhou Institute of TechnologyGuiyang 550003China Merchant Marine college Shanghai Maritime UniversityShanghai 201306China 2011 Special Functional Materials Collaborative Innovation Center of Guizhou Province Guiyang 550003China

CoCrCuFeNi–TiO was prepared by arc melting of the pure elements and Ti_2CO powder under an Ar atmosphere. Both CoCrCuFe Ni and CoCrCuFeNi–TiO alloys are composed of a face-centered cubic(fcc) solid solution, whereas the alloys of CoCrCuFeNi–TiO are basically composed of an fcc solid solution and TiO crystals. The microstructures of CoCrCuFeNi–TiO are identified as dendrite and interdendrite structures such as CoCrCuFeNi. The morphology of TiO is identified as an equiaxed crystal with a small amount of added Ti_2CO. By increasing the amount of Ti_2CO added, the TiO content was dramatically increased and part of the equiaxed crystals changed to a dendrite structure. A test of the oxidation resistance demonstrates that the oxidation resistance of CoCrCuFeNi–TiO is better than that of CoCrCu Fe Ni. However, as the TiO content increases further, a corresponding decrease is observed in the oxidation resistance.

关键词： multicomponent equiatomic high-entropy alloys microstructure oxidation resistance

Numerical and experimental studies of hydrodynamic performance of bionic leading-edge tubercle airfoil

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Journal of Hydrodynamics 2019年第6期31卷 1240-1249页

作者： Chun-yu Guo Zuo-tian Zhang Xu-xiang Cao Tie-cheng wu Yu-min su College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China

This paper studies the bionic tubercle airfoils based on the NACA 0020 prototype airfoil,with 7 models derived from different designs of the span-chord ratios and different tubercle types,along with the option of the wave airfoil surface matching the leading-edge *** water experiments are conducted to test the airfoil profile at a Reynolds number of 3×10^5 and an angle of attack of 0°-30°.Data are recorded by a four-component force balance and the resulted lift,drag,and force moment are *** the analysis of the hydrodynamic characteristics and the flow field characteristics,it is shown that the stall of the tubercle airfoils is milder without an evident stalling angle as compared with that of the normal airfoil *** lift coefficient of the optimized airfoil is significantly elevated at the angle where the NACA 0020 airfoil is in the stall *** lift-drag ratio is also markedly improved at the same *** optimal airfoil profile is finally identified and a further optimization plan is proposed based on the comparison results against the CFD numerical simulation.

关键词： Bionic tubercle computational fluid dynamics stall

Numerical Simulation for the Optimization of Polygonal Pin Profiles in Friction Stir Welding of Aluminum

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Acta Metallurgica Sinica(English Letters) 2021年第8期34卷 1065-1078页

作者： Hao su Chuansong wu MOE Key Lab for Liquid-Solid Structure Evolution and Materials Processing Institute of Materials JoiningShandong UniversityJinan 250061China

The tool with polygonal pin profile has been widely employed in friction stir welding(FSW) of aluminum, but there is hardly an effective optimization methodology existed as the thermomechanical characteristics affected by pins with various flats number have not been understood comprehensively. Therefore, the present work employs a 3-dimensional computational fluid dynamics(CFD) model to have an integrated observation of the FSW process with the effect of polygonal pin profiles. Both the heat generation modes due to contact friction at the tool–workpiece interface and volumetric viscous dissipation in the vicinity of the tool are considered. The model is utilized to give a quantitative analysis of the heat generation, temperature distribution, plastic material flow and welding loads during the FSW process for various tools with polygonal pin profiles, as well as a variety of shoulder diameters, welding speeds and tool rotation speeds. The calculated results of thermal cycles, tool torques and joint cross sections for some typical polygonal pins and welding parameters are all found to be compared well with the experimental ones, which demonstrates the feasibility and applicability of the present numerical model. Particularly, a methodology is developed for the optimization of the flats number by identifying the torque components in both parallel and vertical direction of the pin-side flat region. The results show that the optimized pin flats number increases with increasing tool rotation speed, while the influence of both welding speed and shoulder diameter can be supposed to be insignificant. Moreover, the dependability of the optimized results is also discussed by considering wear tendency and service life of the pin for multiple welding conditions.

关键词： Friction stir welding Polygonal pin Numerical simulation Optimization design Aluminum

Improved MIMO-OFDM scheme for the next generation WLAN

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Journal of Systems Engineering and Electronics 2013年第1期24卷 52-59页

作者： Zhanji wu xiang Gao School of Information and Communication Engineering Beijing University of Posts and Telecommunications

The research and application of wireless local area networks （WLAN） technology are in a stage of rapid development. It has been one of research focuses of the wireless communications field. Through the use of enhanced single-user （su）/multi-user （MU） multiple input multiple output （MIMO）-orthogonal frequency division multiplexing （OFDM） technology, the next generation WLAN IEEE 802.1 lac dramatically increases the throughput. An improved MIMO-OFDM scheme based on modulation diversity is proposed for the next generation WLAN. It uses two-dimensional modulation diversity to the current IEEE 802.11ac transmission scheme. Through the space-time-frequency component inter- leaver and the rotational modulation, the proposed scheme ex- hibits high spectral efficiency and low error rate in fading channels. The simulation results show that the proposed scheme significantly outperforms the su/MU MIMO-OFDM scheme in the current IEEE 802.11 ac standard, which is up to 5 dB.

关键词： wireless local area networks (WLAN) I EEE 802.1 lac modulation diversity multiple input multiple output (MIMO) orthog- onal frequency division multiplexing (OFDM).