检索结果-南通市图书馆

Toward long-life Zn anode using highly polar electrolyte additives

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第2期101卷 651-660页

作者： Nengbin Cai Hongming Chen Busheng Zhang Zijing Liu Xinbo He Dan Zhou Beijing Advanced innovation center for Materials Genome Engineering University of Science and Technology Beijing Shunde innovation School University of Science and Technology Beijing School of Textile Science and Engineering Wuyi University

Unstable Zn interface caused by rampant dendrite growth and parasitic side reactions always hinders the practical application of aqueous zinc metal batteries（AZMBs）,Herein,tyrosine（Tyr） with high molecular polarity was introduced into aqueous electrolyte to modulate the interfacial electrochemistry of Zn *** AZMBs,the positively charged side of Tyr can be well adsorbed on the surface of Zn anode to form a water-poor layer,and the exposed carboxylate side can be easily coordinated with Zn2+,favoring inducing uniform plating of Zn2+and inhibiting the occurrence of water-induced side *** in turn enable the achievement of highly stable Zn ***,the Zn anodes achieve outstanding cyclic stability(3000 h at 2 mA cm-2,2 mA h cm-2and 1300 h at 5 mA cm-2,5 mA h cm-2),high average Coulombic efficiency（99.4% over 3200 cycles）,and high depth of discharge（80% for 500 h）.Besides,the assembled Zn‖NaV3O8·1.5H2O full cells deliver remarkable capacity retention and ultra-long lifetime(61.8% over 6650 cycles at 5 A g-1) and enhanced rate capability(169 mA h g-1at 5 A g-1).The work may promote the design and deep understanding of electrolyte additives with high molecular polarity for high-performance AZMBs.

关键词： AZMBs Electrolyte additives Highly stable Zn anode Interfacial electrochemistry Tyr

An asymmetrically variable wingtip anhedral angles morphing aircraft based on incremental sliding mode control:Improving lateral maneuver capability

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2025年第1期38卷 455-470页

作者： Xiaodong LIU Yong XU Jianqiao LUO School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing innovation center Beijing Institute of TechnologyChongqing 401120China

This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver ***,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual ***,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown *** whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function ***,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and *** dynamic models are incorporated to ensure physical realizability of designed allocation ***,comparative experimental results validate the effectiveness of the designed control system and control allocation *** NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),*** design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering.

关键词： Morphing aircraft Lateral maneuver capability Incremental sliding mode control Multi-Lyapunov function method Control theory Control allocation law

Status analysis on sputtering and erosion evaluation methods of ion optic systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2025年第1期38卷 254-270页

作者： Long MIAO Tongxun YANG Zhengxi ZHU Chang LU Zhiwen WU Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing innovation center Beijing Institute of TechnologyChongqing 404100China Advanced Aerospace Power and Energy Research center Beijing Institute of TechnologyZhuhai 519088China

In the past few decades,ion engines have been widely used in deep-space propulsion and satellite *** aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion *** one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming *** this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid *** advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are *** different types of experimental methods of grid assembly erosion patterns are *** analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid ***,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime.

关键词： Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation

Mixed-charge glycopolypeptides as antibacterial coatings with long-term activity

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2025年第2期36卷 270-278页

作者： Fangping Yang Jin Shi Yuansong Wei Qing Gao Jingrui Shen Lichen Yin Haoyu Tang Institute of Functional Nano & Soft Materials(FUNSOM) Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow University

Planktonic bacteria adhere and subsequently form biofilms on implantable medical devices can cause severe infections that have become the major types of hospital-acquired infections. Traditional coatings for the implants are frequently lack of long-term antifouling and bactericidal activities. It is still a big challenge to simultaneously improve the antifouling and bactericidal activities of the coatings. Herein,we report that mixed-charge glycopolypeptide coatings are of long-term antibacterial activities to efficiently inhibit the biofilm growth. The glycosylation of mixed-charge polypeptides has led to a significant improvement of both antifouling and bactericidal activities. The cooperative effect of the saccharide residues and mixed-charge residues improved the resistance of the polypeptide coatings against protein adsorption. The saccharide and L-glutamic acid(E) residues collectively enhanced the bacterial membrane-disruption of cationic L-lysine(K) residues, leading to potent bactericidal activity. Meanwhile,the glycopolypeptide coatings showed superior biocompatibility, long-term antibiofilm and anti-infection properties in two types of mouse subcutaneous infection models and one type of mouse urinary tract infection model. This work provides a new strategy to achieve antibacterial coatings with long-term activities for preventing implantable medical device associated infections.

关键词： Antibacterial coating Bactericidal activity Biofilm Fouling Glycopolypeptide

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： Xia JIANG Yanyan FANG Xianlin ZENG Jian SUN Jie CHEN National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of technology Chongqing innovation center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie ZHANG Cancan WU Yuting ZHANG Yi LU Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of TechnologyBeijing 100124China

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings(φ),i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/(Δp)^(1/3)was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29%to 17.18%over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

维普期刊数据库

Likelihood-based modified Kalman filter for estimating vehicle lateral states with random measurement delay

在线全文

学校读者我要写书评

暂无评论

Science China Technological Sciences 2025年第3期68卷 314-322页

作者： Chao YANG Ruixin ZHANG Weida WANG Yuhang ZHANG Jiayi FANG Qi WANG Shouwen YAO School of Mechanical Engineering Beijing Institute of Technology Chongqing innovation center Beijing Institute of Technology

Accurate lateral state estimation is crucial for ensuring the stability and safety of vehicles. The Kalman filter is widely utilized to estimate the lateral state of vehicles. However, vehicle state measurement suffers from inherent time delays and model discrepancies. The existence of fractional and random delays necessitates long sampling periods for the inputs of the Kalman filter,leading to update mismatch and deterioration of the accuracy of the estimation. This situation poses a threat to driving *** addition, the tire cornering stiffness, a critical model parameter, exhibits nonlinear and dynamic variations that cannot be measured in real time. This inherent variability significantly affects the accuracy of lateral state estimation. Considering internal and external uncertainties, an observer framework for vehicle lateral state estimation based on the Kalman filter was designed in this work. First, a modified delayed Kalman filter method that considers the random fractional delays was developed. The relationship correlation between the delayed measurement and the prior state was constructed based on a likelihood ***, the tire cornering stiffness was estimated online by an algorithm based on recursive least squares. This parameter was used to dynamically adjust the vehicle model for the Kalman filter. Finally, two simulations and a real vehicle experiment were performed to verify the effectiveness of the proposed method. In particular, the root mean squared error(RMSE) of the slip angle decreased by 30.70%, and that of the yaw rate decreased by 61.03% in the double lane change scenario. Actual vehicle experiments demonstrated that the algorithm can be effectively applied in real situations.

关键词： measurement delay Kalman filter parameter identification likelihood estimation

Taming of trinitromethyl-oxadiazole to access high density and high oxygen balance via a dual modulation strategy

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Defence technology(防务技术) 2025年第1期43卷 142-149页

作者： Jinya Zhang Teng Fei Jingwei Meng Jinxiong Cai Lei Zhang Siping Pang Chunlin He School of Materials Science&Engineering Beijing Institute of TechnologyBeijing 100081China Experimental center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China hongqing innovation center Beijing Institute of TechnologyChongqing 401120China

Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense *** this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive *** this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic ***,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),***,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and *** work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials.

关键词： Energetic materials High oxygen balance High density Dual modulation Trinitromethyl group

维普期刊数据库

Potential dependence in electrocatalysis:a theoretical perspective

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming Xia Zeyu Wang Yinjuan Chen Hai Xiao Department of Chemistry Tsinghua UniversityBeijing 100084China Fundamental Science center of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119China Key Laboratory of Advanced Catalytic Materials and technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China

Electrocatalysis is a key technology for the new energy era and sustainable development,serving as the interface for interconversion of electrical and chemical energies,which spans a wide spectrum of applications in sustainable energy and environmental *** reactions including electrochemical CO_(2)reduction reaction(eCO_(2)RR),hydrogen evolution reaction(HER),and oxygen evolution/reduction reactions(OER/ORR),hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

关键词： spectrum interface Electrocatalysis

维普期刊数据库