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Regulating zinc ion transport behavior and solvated structure towards stable aqueous Zn metal batteries

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Journal of Energy Chemistry 2024年第6期93卷 609-626,I0015页

作者： qiang Ma Aoen Ma Shanguang lv Bowen Qin Yali Xu Xianxiang Zeng wei Ling Yuan Liu Xiongwei Wu College of Materials Engineering Henan International Joint Laboratory of Rare Earth Composite MaterialsHenan University of EngineeringZhengzhou 451191HenanChina Nanozyme Medical Center School of Basic Medical SciencesZhengzhou UniversityZhengzhou 450001HenanChina School of Chemistry and Materials Science Hunan Agricultural UniversityChangsha 410125HunanChina College of Electrical and Information Engineering Hunan UniversityChangsha 410082HunanChina Hunan Province Yin Feng New Energy Co.Ltd. Changsha 410019HunanChina

Aqueous Zn metal batteries(AZMBs)with intrinsic safety,high energy density and low cost have been regarded as promising electrochemical energy storage ***,the parasitic reaction on metallic Zn anode and the incompatibility between electrode and electrolytes lead to the deterioration of electrochemical performance of AZMBs during the *** critical point to achieve the stable cycling of AZMBs is to properly regulate the zinc ion solvated structure and transfer behavior between metallic Zn anode and *** recent years,numerous achievements have been made to resolve the formation of Zn dendrite and interface incompatible issues faced by AZMBs via optimizing the sheath structure and transport capability of zinc ions at electrode-electrolyte *** this review,the challenges for metallic Zn anode and electrode-electrolyte interface in AZMBs including dendrite formation and interface characteristics are *** the influences of different strategies involving designing advanced electrode structu re,artificial solid electrolyte interphase(SEI)on Zn anode and electrolyte engineering to regulate zinc ion solvated sheath structure and transport behavior are summarized and ***,the perspectives for the future development of design strategies for dendrite-free Zn metal anode and long lifespan AZMBs are also given.

关键词： aqueous Zn metal batteries Zn metal anode Transport behavior Solvated structure Dendrite-free

Coupled Lagrangian impingement spray model for doublet impinging injectors under liquid rocket engine operating conditions

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Chinese Journal of Aeronautics 2017年第4期30卷 1391-1406页

作者： qiang wei Guozhu LIANG School of Astronautics Beihang University Beoing 100083 China

To predict the effect of the liquid rocket engine combustion chamber conditions on the impingement spray, the conventional uncoupled spray model for impinging injectors is extended by considering the coupling of the jet impingement process and the ambient gas field. The new coupled model consists of the plain-orifice sub-model, the jet-jet impingement sub-model and the droplet collision sub-model. The parameters of the child droplet are determined with the jet-jet impingement sub-model using correlations about the liquid jet parameters and the chamber *** overall model is benchmarked under various impingement angles, jet momentum and offcenter ratios. Agreement with the published experimental data validates the ability of the model to predict the key spray characteristics, such as the mass flux and mixture ratio distributions in quiescent air. Besides, impinging sprays under changing ambient pressure and non-uniform gas flow are investigated to explore the effect of liquid rocket engine chamber conditions. First, a transient impingement spray during engine start-up phase is simulated with prescribed pressure profile. The minimum average droplet diameter is achieved when the orifices work in cavitation state, and is about 30% smaller than the steady single phase state. Second, the effect of non-uniform gas flow produces off-center impingement and the rotated spray fan by 38°. The proposed model suggests more reasonable impingement spray characteristics than the uncoupled one and can be used as the first step in the complex simulation of coupling impingement spray and combustion in liquid rocket engines.

关键词： Combustion chamber Doublet impinging injector Impingement spray model Lagrangian method Liquid rocket engine

Kinematics-based four-state trajectory tracking control of a spherical mobile robot driven by a 2-DOF pendulum

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Chinese Journal of Aeronautics 2019年第6期32卷 1530-1540页

作者： wei LI qiang ZHAN Robotics Institute Beihang UniversityBeijing 100083China Ecole Centrale de Pékin Beihang UniversityBeijing 100083China

Spherical mobile robot has compact structure, remarkable stability, and flexible motion,which make it have many advantages over traditional mobile robots when applied in those unmanned environments, such as outer planets. However, spherical mobile robot is a special highly under-actuated nonholonomic system, which cannot be transformed to the classic chained form. At present, there has not been a kinematics-based trajectory tracking controller which could track both the position states and the attitude states of a spherical mobile robot. In this paper, the four-state(two position states and two attitude states) trajectory tracking control of a type of spherical mobile robot driven by a 2-DOF pendulum was studied. A controller based on the shunting model of neurodynamics and the kinematic model was deduced, and its stability was demonstrated with Lyapunov’s direct method. The control priorities of the four states were allocated according to the magnification of each state tracking error in order to firstly ensure the correct tracking of the position states. The outputs(motor speeds) of the controller were regulated according to the maximum speeds and the maximum accelerations of the actuation motors in order to solve the speed jump problem caused by initial state errors, and continuous and bounded outputs were obtained. The effectiveness including the anti-interference ability of the proposed trajectory tracking controller was verified through MATLAB simulations.

关键词： Kinematics Lyapunov methods Neurodynamics Nonholonomic systems Spherical mobile robot Trajectory tracking

From Liquid to Solid‑State Lithium Metal Batteries:Fundamental Issues and Recent Developments

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Nano-Micro Letters 2024年第2期16卷 68-125页

作者： Zhao Zhang wei‑qiang Han School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027People’s Republic of China

The widespread adoption of lithium-ion batteries has been driven by the proliferation of portable electronic devices and electric vehicles,which have increasingly stringent energy density *** metal batteries(LMBs),with their ultralow reduction potential and high theoretical capacity,are widely regarded as the most promising technical pathway for achieving high energy density *** this review,we provide a comprehensive overview of fundamental issues related to high reactivity and migrated interfaces in ***,we propose improved strategies involving interface engineering,3D current collector design,electrolyte optimization,separator modification,application of alloyed anodes,and external field regulation to address these *** utilization of solid-state electrolytes can significantly enhance the safety of LMBs and represents the only viable approach for advancing *** review also encompasses the variation in fundamental issues and design strategies for the transition from liquid to solid *** noteworthy is that the introduction of SSEs will exacerbate differences in electrochemical and mechanical properties at the interface,leading to increased interface inhomogeneity—a critical factor contributing to failure in all-solidstate lithium metal *** on recent research works,this perspective highlights the current status of research on developing high-performance LMBs.

关键词： Lithium metal batteries All-solid-state lithium metal battery Li dendrite Solid electrolyte Interface

Existence of Positive Periodic Solutions for Nonautonomous Predator-prey Systems with Discrete and Continuously Distributed Delays

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Acta Mathematicae Applicatae Sinica 2007年第1期23卷 39-48页

作者： Yan lv wei lv Jian-hua Sun Department of Mathematics Nanjing University Nanjing 210008 China Department of Mathematics Xi'an Jiao Tong University Xi'an 710049 China

By using the continuation theorem of coincidence degree theory, the sufficient conditions to guarantee the existence of positive periodic solutions are established for nonautonomous predator-prey systems with discrete... 详细信息

关键词： Predator-prey system time delay positive periodic solution Fredholm operator coincidence degree

Recent Advances and Perspectives of Lewis Acidic Etching Route:An Emerging Preparation Strategy for MXenes

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Nano-Micro Letters 2023年第5期15卷 187-235页

作者： Pengfei Huang wei-qiang Han School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027People’s Republic of China

Since the discovery in 2011,MXenes have become the rising star in the field of two-dimensional *** from the metallic-level conductivity,large and adjustable gallery spacing,low ion diffusion barrier,rich surface chemistry,superior mechanical strength,MXenes exhibit great application prospects in energy storage and conversion,sensors,optoelectronics,electromagnetic interference shielding and ***,two issues seriously deteriorate the further development of *** is the high experimental risk of common preparation methods such as HF etching,and the other is the difficulty in obtaining MXenes with controllable surface ***,Lewis acidic etching,as a brand-new preparation strategy for MXenes,has attracted intensive attention due to its high safety and the ability to endow MXenes with uniform ***,a comprehensive review of Lewis acidic etching method has not been reported ***,we first introduce the Lewis acidic etching from the following four aspects:etching mechanism,terminations regulation,in-situ formed metals and delamination of multi-layered ***,the applications of MXenes and MXene-based hybrids obtained by Lewis acidic etching route in energy storage and conversion,sensors and microwave absorption are carefully ***,some challenges and opportunities of Lewis acidic etching strategy are also presented.

关键词： Lewis acidic etching MXenes Etching mechanism Termination regulation In-situ formed metals Delamination Application

定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLO W_(6)C_(6)团簇

维普期刊数据库博看期刊

Sliding Dynamics of Slide-Ring Polymers Based on the Bead-Spring Model

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Chinese Journal of Polymer Science 2023年第9期41卷 1410-1424,I0007页

作者： Zhong-qiang Xiong wei Yu Advanced Rheology Institute Department of Polymer Science and EngineeringState Key Laboratory for Metal Matrix Composite MaterialsShanghai Jiao Tong UniversityShanghai200240China

Understanding the sliding dynamics is critical for developing rotaxane-based mechanically interlocked *** this work,we studied the sliding behavior of a sliding ring and its influence on the dynamics of attached polymer chains based on the heterogeneous beadspring *** sliding constraint was treated as direction-related confinement with the heterogeneous friction coefficient and constraint *** relaxation spectrum,the diffusion dynamics,and the sliding dynamics under/after drag were studied for typical sliding chain topologies,namely,the sliding dangling chain,the constraint sliding chain,and the sliding *** with the non-sliding chains(such as the free chain,the dangling chain,and the network strand),the slide of one or two chain ends induces an additional slow process in the transition from the Rouse-type behavior to the long-time terminal *** effect of the sliding-related process on the diffusion of specific chain segments relies on the chain *** slow sliding relaxation process is also observed in the sliding process during and after chain deformation,whose characteristic time is at least three times the terminal relaxation time of the free chain with the same length,and will increase with the friction coefficient(i.e.,the interaction)between the ring and the polymer *** results of this work will benefit the understanding of the sliding dynamics in experiments.

关键词： Sliding chain Bead-spring model Heterogeneity Diffusion Mean conformation

Optimization of preparation process of high-strength pellets from Panzhihua ilmenite concentrate

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Journal of Iron and Steel Research International 2023年第12期30卷 2391-2402页

作者： Gang-wei Zhou wei lv Fu-rong Chen Zheng-gen Liu Man-sheng Chu Xue-wei lv School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina College of Materials Science and Engineering Chongqing UniversityChongqing400044China

The preparation of high-strength pellets from Panzhihua ilmenite concentrate is important for the hydrogen-rich smelting of titania slag and was *** effects of the magnetite concentrate and heating procedure including the pre-heating temperature and period as well as roasting temperature and period on the compressive strength of the roasted pellets were ***-strength ilmenite concentrate pellets(>2000 N)were prepared by optimizing the roasting *** addition of magnetite concentrate is beneficial for increasing the compressive strength of the Panzhihua ilmenite concentrate pellet by oxidizing hematite which filled the pseudobrookite particles,functioned as a bridge bond,and improved the interconnection between the *** compressive strength can reach up to 2900 N when the ilmenite concentrate pellet with 15%magnetite concentrate is pre-heated above 800℃ for 20 min and then roasted at 1250℃ for 20 *** addition,there is an overall upward trend in the compressive strength with an increase in the pre-heating temperature and period as well as the roasting temperature and *** micromorphology and strengthening consolidation mechanism of Panzhihua ilmenite concentrate pellets were also discussed.

关键词： Ilmenite concentrate Pelletizing Roasting Compressive strength-Pellet