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Selective N-Methylation of N-Methylaniline with CO_(2) and H_(2) over Cu/In_(2)O_(3) Catalyst

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Chinese Journal of Chemistry 2024年第3期42卷 276-282页

作者： Huan Zheng Bo qian Lin He State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of Chinese Academy of Sciences Beijing100049 China

N-Methylation of amines with CO_(2) and H2 is a potential approach for CO_(2) utilization because N-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported Cu (Cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for N-methylation reaction of N-methylaniline (MA) with CO_(2) and H_(2),showing higher N,N-dimethylaniline (DMA) selectivity than other supported Cu catalysts. On one hand,the dispersion of Cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of CO_(2) through C—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by Cu. The combination of Cu and In_(2)O_(3) is effective in the activation of CO_(2),the adsorption of intermediate N-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of C—N bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： N-Methylation CO_(2) Cu/In_(2)O_(3) Supported catalysts Heterogeneous catalysis

Preface to the“Theory and Applications of Flexoelectricity”Special Issue of Acta Mechanica Solida Sinica

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Acta Mechanica Solida Sinica 2024年第4期37卷 519-520页

作者： qian Deng Yue Zheng Shengping Shen School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074China School of Physics Sun Yat-sen UniversityGuangzhou510275China School of Aerospace Engineering Xi’an Jiaotong UniversityXi’an710049China

Flexoelectricity refers to the electric polarization generated by non-uniform mechanical strains within dielectric materials and *** intriguing effect bridges the fields of materials science,mechanical engineering,and applied physics,offering a promising avenue for innovation in sensor technology,energy harvesting,multiphysics field coupling,among others.

关键词： offering bridges harvesting

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu qian-qian Shi Yu-Feng Meng Yong Zhou Li-Bo Mao Shu-Hong Yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Novel Adaptive Memory Event-Triggered-Based Fuzzy Robust Control for Nonlinear Networked Systems via the Differential Evolution Algorithm

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1836-1848页

作者： Wei qian Yanmin Wu Bo Shen School of Electrical Engineering and Automation Henan Polytechnic UniversityJiaozuo 454000China College of Information Science and Technology Donghua UniversityShanghai 201620China

This article mainly investigates the fuzzy optimization robust control issue for nonlinear networked systems characterized by the interval type-2(IT2)fuzzy technique under a differential evolution *** provide a more reasonable utilization of the constrained communication channel,a novel adaptive memory event-triggered(AMET)mechanism is developed,where two event-triggered thresholds can be dynamically adjusted in the light of the current system information and the transmitted historical *** conditions with less conservative design of the fuzzy imperfect premise matching(IPM)controller are presented by introducing the Wirtinger-based integral inequality,the information of membership functions(MFs)and slack ***,under the IPM policy,a new MFs intelligent optimization technique that takes advantage of the differential evolution algorithm is first provided for IT2 TakagiSugeno(T-S)fuzzy systems to update the fuzzy controller MFs in real-time and achieve a better system control ***,simulation results demonstrate that the proposed control scheme can obtain better system performance in the case of using fewer communication resources.

关键词： Adaptive memory event-triggered(AMET) differential evolution algorithm fuzzy optimization robust control interval type-2(IT2)fuzzy technique.

Reveal more mechanisms of precondition mesenchymal stem cells inhibiting inflammation

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World Journal of Stem Cells 2024年第4期16卷 459-461页

作者： Yi Li qian-qian Chen En-qiang Linghu Department of Gastroenterology First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Gastroenterology and Hepatology First Medical Center of Chinese PLA General HospitalBeijing 100853China

Hypoxia can get more ability to inhibit *** how it impact on survival time of mesenchymal stem cells(MSCs)is confusing and how preconditioned MSCs inhibiting inflammation are partially *** issues decided the value of ... 详细信息

关键词： Mesenchymal stem cell Hypoxia-inducible factor 1α Hypoxia Inflammation Macrophage

SAC-Based Computation Offloading for Reconfigurable Intelligent Surface-Aided Mobile Edge Networks

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China Communications 2024年第6期21卷 261-270页

作者： Li Bin qian Zhen Fei Zesong School of Computer Science Nanjing University of Information Science&TechnologyNanjing 210044China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET) Nanjing University of Information Science&TechnologyNanjing 210044 School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

In this paper,we concentrate on a reconfigurable intelligent surface(RIS)-aided mobile edge computing(MEC)system to improve the offload efficiency with moving user equipments(UEs).We aim to minimize the energy consumption of all UEs by jointly optimizing the discrete phase shift of RIS,UEs’transmitting power,computing resources allocation,and the UEs’task offloading strategies for local computing and *** formulated problem is a sequential decision making across multiple coherent time ***,the mobility of UEs brings uncertainties into the decision-making *** cope with this challenging problem,the deep reinforcement learning-based Soft Actor-Critic(SAC)algorithm is first proposed to effectively optimize the discrete phase of RIS and the UEs’task offloading ***,the transmitting power and computing resource allocation can be determined based on the *** results demonstrate that the proposed algorithm can be trained more stably and perform approximately 14%lower than the deep deterministic policy gradient benchmark in terms of energy consumption.

关键词： MEC RIS soft actor-critic user mobility

Refinement modeling and verification of secure operating systems for communication in digital twins

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Digital Communications and Networks 2024年第2期10卷 304-314页

作者： Zhenjiang qian Gaofei Sun Xiaoshuang Xing Gaurav Dhiman School of Computer Science and Engineering Changshu Institute of TechnologySuzhou215500China University Centre for Research and Development Department of Computer Science and EngineeringChandigarh UniversityMohali140413India Department of Computer Science and Engineering Graphic Era Deemed to be UniversityDehradun248002India

In traditional digital twin communication system testing,we can apply test cases as completely as possible in order to ensure the correctness of the system implementation,and even then,there is no guarantee that the digital twin communication system implementation is completely *** verification is currently recognized as a method to ensure the correctness of software system for communication in digital twins because it uses rigorous mathematical methods to verify the correctness of systems for communication in digital twins and can effectively help system designers determine whether the system is designed and implemented *** this paper,we use the interactive theorem proving tool Isabelle/HOL to construct the formal model of the X86 architecture,and to model the related assembly *** verification result shows that the system states obtained after the operations of relevant assembly instructions is consistent with the expected states,indicating that the system meets the design expectations.

关键词： Theorem proving Isabelle/HOL Formal verification System modeling Correctness verification

Emerging perovskite materials for supercapacitors:Structure,synthesis,modification,advanced characterization,theoretical calculation and electrochemical performance

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Journal of Energy Chemistry 2024年第2期89卷 41-70,I0003页

作者： Yuehua qian Qingqing Ruan Mengda Xue Lingyun Chen Department of Applied Chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 401331China

As a new generation electrode materials for energy storage,perovskites have attracted wide attention because of their unique crystal structure,reversible active sites,rich oxygen vacancies,and good *** this review,the design and engineering progress of perovskite materials for supercapacitors(SCs)in recent years is ***,the review will focus on four types of perovskites,perovskite oxides,halide perovskites,fluoride perovskites,and multi-perovskites,within the context of their intrinsic structure and corresponding electrochemical performance.A series of experimental variables,such as synthesis,crystal structure,and electrochemical reaction mechanism,will be carefully analyzed by combining various advanced characterization techniques and theoretical *** applications of these materials as electrodes are then featured for various ***,we look forward to the prospects and challenges of perovskite-type SCs electrodes,as well as the future research direction.

关键词： Perovskite Modification engineering Oxygen vacancy Theoretical calculation methodology Supercapacitor

Further Results on Stability Analysis for Sampled-Data Systems via Refined Semi-Looped-Functional

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Journal of Systems Science & Complexity 2024年第1期37卷 318-328页

作者： SHENG Zhaoliang XU Shengyuan MA qian ZHANG Baoyong School of Automation Nanjing University of Science and TechnologyNanjing 210094China

This paper investigates the stability problem for sampled-data systems by adopting a refined semi-looped-functional,which is with the following two ***,the new functional term is with a new integral vectorη0,which contains sampling information of the systems and associates two commonly used ***,the vectorη0 is combined into various zero equations for processing the functional,especially where a new equation is derived fromη*** on the refined functional,further stability results for sampled-data systems are *** the effectiveness of the results is numerically verified through two examples at the end.

关键词： Integral vector sampled-data systems semi-looped-functional stability analysis.