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Synergy of inside doped metals–Outside coated graphene to enhance hydrogen storage in magnesium-based alloys

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Journal of Magnesium and Alloys 2024年第6期12卷 2462-2471页

作者： kun Zhang Yu Chang Jingjing Lei Jing Chen Tingzhi si Xiaoli Ding Ping Cui Hai-Wen li Qingan Zhang Yongtao li School of Materials Science and Engineering&Low-Carbon New Materials Research Center Anhui University of TechnologyMaanshanAnhui 243002China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084 Hefei General Machinery Research Institute HefeiAnhui 230031China Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials of Ministry of Education Anhui University of TechnologyMaanshan 243002China

Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption *** solve this problem,herein we propose a novel method involving synergistic effect of inside embedded metals and outside coated graphene to limit the growth of Mg and its hydride *** graphene coated Mg-Y-Al alloys were selected as a model system for demonstrating this positive effect where the Mg_(91)Y_(3)Al_(6)alloy was first prepared by rapidly solidified method and then high-pressure milled with 5 wt%graphene upon 5 MPa hydrogen gas for obtaining in-situ formed YAl_(2)and YH_(3)embedded in the MgH_(2)matrix with graphene shell(denoted as MgH_(2)-Y-Al@GR).In comparison to pure MgH_(2),the obtained MgH_(2)-Y-Al@GR composites deliver much better kinetics and more stable cyclic *** instance,the MgH_(2)-Y-Al@GR can release about 6.1 wt%H_(2)within 30 min at 300℃ but pure MgH_(2)only desorbs∼1.5 wt%H_(2).The activation energy for desorption of MgH_(2)-Y-Al@GR samples is calculated to be 75.3±9.1 kJ/mol that is much lower than approximately 160 kJ/mol for pure MgH_(2).Moreover,its capacity retention is promoted from∼57%of pure MgH_(2)to∼84%after 50th cycles without obvious particle agglomeration and grain *** synergistic effect of outside graphene coating with inside embedded metals which could provide a huge number of active sites for catalysis as well as inhibit the grain growth of Mg and its hydride is believed to be responsible for these.

关键词： Energy Hydrogen storage Mg alloys Synergy effect

Ultrahigh strength and uniform corrosion in Zn-li alloys through ultrahigh pressure supersaturated solid solution treatment for biodegradable orthopedic applications

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Rare Metals 2024年第10期43卷 5284-5304页

作者： Wan-Ying li Yi-Long Dai Wen-Hao Cai si-Han lin lin Guo De-Chuang Zhang Yuncang li Cuie Wen School of Materials Science and Engineering Xiangtan University Department of Prosthodontics Shanghai Ninth People′s HospitalShanghai Jiao Tong University Key Laboratory of Low Dimensional Materials&Application Technology Ministry of EducationXiangtan University School of Engineering RMIT UniversityMelbourne

Zn-li alloys are considered promising candidate materials for biodegradable orthopedic implant applications due to their high mechanical performance and good ***,the presence of a large number of second-phase particles in this class of Zn alloys can lead to severe localized degradation due to micro-galvanic corrosion,which is detrimental to the mechanical integrity of the alloys during tissue healing in the human *** this study we report ultrahigh strength,uniform corrosion,good cytocompatibility,and effective antibacterial ability in Zn-x li（x=0.3,0.5,0.7;wt%） alloys achieved through supersaturated solid solution treatment （SSST） at 375℃ under ultrahigh pressure of 3 GPa.A high concentration of β-liZn4phases coexisted with the-Zn matrix in the as-cast Zn-x li alloys,whereas almost all the li dissolved into the-Zn matrix of SSST *** yield strength was 437 MPa for SSST Zn-0.3li,592 MPa for SSST Zn-0.5 li and 686 MPa for SSST *** SSST Zn-li alloys showed uniform degradation with remarkably reduced degradation rates compared to their as-cast *** 25% concentration extracts of the Zn-x li alloys demonstrated no cytotoxicity toward MC3T3-E1 cells,and the alloys exhibited effective antibacterial ability agains methicillin-resistant staphylococcus aureus.

关键词： Corrosion behavior Mechanical property Supersaturated solid solution treatment (SSST) Ultrahigh pressure Zn-li alloy

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描述任务逻辑及其应用

计算机学报 2006年第3期29卷 488-494页

作者：张会李思昆国防科学技术大学计算机学院长沙410073

针对任务逻辑存在的两个缺点:(1)不可判定,无法保证推理过程都能在有限的时间内结束;(2)任务的定义局限于抽象的、逻辑的定义,无法描述任务的具体属性和任务之间的关系,将描述性结构引入任务逻辑,构造了一个可描述具体属性的、可判定的... 详细信息

针对任务逻辑存在的两个缺点:(1)不可判定,无法保证推理过程都能在有限的时间内结束;(2)任务的定义局限于抽象的、逻辑的定义,无法描述任务的具体属性和任务之间的关系,将描述性结构引入任务逻辑,构造了一个可描述具体属性的、可判定的任务逻辑系统———描述任务逻辑.将所构造的逻辑系统应用于具有组织的多主体系统行为建模,建立了基于描述任务逻辑的多主体组织模型和建模框架,并且表明应用描述任务逻辑构造应用系统具有表达能力强、结构紧凑的特点.

关键词：任务逻辑可判定描述语言多主体系统组织模型

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适于社会网络结构分析与可视化的布局算法

软件学报 2011年第10期22卷 2467-2475页

作者：吴鹏李思昆国防科学技术大学计算机学院湖南长沙410073

力导引布局算法是社会网络信息可视化领域的主流布局算法,但却在结构分析显示方面存在缺陷.产生的图像经常是节点聚集在屏幕中央,难以分辨结构信息.因此,提出了子群分析布局SAL(subgroup analysis layout)算法来解决这一问题.该算法通... 详细信息

力导引布局算法是社会网络信息可视化领域的主流布局算法,但却在结构分析显示方面存在缺陷.产生的图像经常是节点聚集在屏幕中央,难以分辨结构信息.因此,提出了子群分析布局SAL(subgroup analysis layout)算法来解决这一问题.该算法通过角色分析和关键属性分析,对社会网络中的子群进行划分与分析,然后根据子群分析结果对力导引布局算法加以改进,包括2D和3D可视化.以对恐怖组织信息进行分析作为实例,也验证了SAL算法在社会网络结构分析与显示方面具有一定的优越性.

关键词：信息可视化社会网络力导引布局算法结构分析子群分析

Predict the evolution of mechanical property of Al-li alloys in a marine environment

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Defence Technology（防务技术） 2024年第1期31卷 557-566页

作者： Wei li lin Xiang Guang Wu Hongli si Jinyan Chen Yiming Jin Yan Su Jianquan Tao Chunyang Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100036China Chongqing Innovation Center Beijing Institute of TechnologyChongqing400044China First Research Institute of the Ministry of Public Security for PR China Beijing100036China Southwest Technology and Engineering Research Institute Chongqing400039China

The ocean is one of the essential fields of national defense in the future,and more and more attention is paid to the lightweight research of Marine equipment and *** study it is to develop a Machine learning(ML)-based prediction method to study the evolution of the mechanical properties of Al-li alloys in the marine *** obtained the mechanical properties of Al-li alloy samples under uniaxial tensile deformation at different exposure times through Marine exposure *** obtained the strain evolution by digital image correlation(DIC).The strain field images are voxelized using 2D-Convolutional Neural Networks(CNN)autoencoders as input data for Long Short-Term Memory(LSTM)neural ***,the output data of LSTM neural networks combined with corrosion features were input into the Back Propagation(BP)neural network to predict the mechanical properties of Al-li *** main conclusions are as follows:*** variation law of mechanical properties of2297-T8 in the Marine atmosphere is *** the increase in outdoor exposure test time,the tensile elastic model of 2297-T8 changes slowly,within 10%,and the tensile yield stress changes significantly,with a maximum attenuation of 23.6%.*** prediction model can predict the strain evolution and mechanical response simultaneously with an error of less than 5%.*** study shows that a CNN/LSTM system based on machine learning can be built to capture the corrosion characteristics of Marine exposure *** results show that the relationship between corrosion characteristics and mechanical response can be predicted without considering the microstructure evolution of metal materials.

关键词： Marine environment Al-li alloy Machine learning Corrosion

Adaptive Consensus of Uncertain Multi-Agent Systems With Unified Prescribed Performance

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IEEE/CAA Journal of Automatica sinica 2024年第5期11卷 1310-1312页

作者： kun li Kai Zhao Yongduan Song The authors are with the School of Automation Chongqing UniversityChongqing 400044China

Dear Editor,An adaptive consensus control algorithm for uncertain multi-agent systems(MAS),capable of guaranteeing unified prescribed performance,is presented in this *** many existing prescribed performance related works,the developed control exhibits some ***,a distributed prescribed time observer is introduced so that not only each follower is able to estimate the leader’s signal within a predetermined time,but also the control design for each agent is independent with its neighbors.

关键词： agent prescribed Uncertain

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基于悖论分析和增量求解的快速反例压缩算法

软件学报 2006年第5期17卷 1034-1041页

作者：沈胜宇李思昆国防科学技术大学计算机学院湖南长沙410073

使用反例压缩算法,从反例中剔除冗余信息,从而使反例易于理解,是目前的研究热点.然而,目前压缩率最高的BFL（brute force lifting）算法,其时间开销过大.为此,提出一种基于悖论分析和增量式SAT（boolean satisfiablilty problem）的快... 详细信息

使用反例压缩算法,从反例中剔除冗余信息,从而使反例易于理解,是目前的研究热点.然而,目前压缩率最高的BFL（brute force lifting）算法,其时间开销过大.为此,提出一种基于悖论分析和增量式SAT（boolean satisfiablilty problem）的快速反例压缩算法.首先,根据反证法和排中律原理,该算法对每一个自由变量v,构造一个SAT问题,以测试v是否能够避免反例.而后对其中不可满足的SAT问题,进行悖论分析,抽取出导致悖论的变量集合.所有不属于该集合的变量,均可作为无关变量直接剔除.同时,该算法使用增量式SAT求解方法,以避免反复搜索冗余状态空间.理论分析和实验结果表明,与BFL算法相比,该算法能够在不损失压缩率的前提下获得1～2个数量级的加速.

关键词：模型检验反例压缩悖论分析增量式求解安全断言

An effective strategy for dendrite free li metal anodes:Nickel foam decorated with high lattice-matching CoN and CoF_(2) nanosheets for dense deposition

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Nano Research 2024年第5期17卷 4069-4078页

作者： Wenlong liu Jianzong Man Xiaodong Sun Ning Zhang Yehong Du kun liu Zhongsheng Wen Song li Juncai Sun Institute of Materials and Technology Dalian Maritime UniversityDalian 116026China Shandong Provinvial Key Laboratory of Chemical Energy Storage and Novel Cell Technology and School of Chemistry and Chemical enginneringLiaocheng UniversityLiaocheng 252000China Department of Public Security Management Liaoning Police CollegeDalian 116036China

The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/***,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free *** Ni foam offers abundant space to receive deposited li *** CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of li^(+)***,the nanosheet structure with lithiophilicity would accelerate the move of li+and decrease the nucleation barrier,due to the high lattice-matching of li and ***,the CoF_(2) could increase the content of F(liF)in the SEI layer,which enhances the strength and avoids the destruction of SEI *** the cooperation of CoN and CoF_(2),the composited anode(li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the liFePO_(4) and li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic *** strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.

关键词： CoN and CoF_(2) lattice-matching nanosheet lithiophilicity lithium metal anodes

Effectiveness of cardioneuroablation in different subtypes of vasovagal syncope

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Journal of Geriatric Cardiology 2024年第6期21卷 651-657页

作者： Bin TU Zi-Hao LAI Ai-Yue CHEN Zhi-Yuan WENG si-Min CAI Zhu-Xin ZHANG li-kun ZHOU li-Hui ZHENG Yan YAO Arrhythmia Center Fuwai HospitalNational Center for Cardiovascular DiseasesNational Key LaboratoryChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Cardiac Center Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina Cardiovascular Department The First Affiliated HospitalFujian Medical UniversityFujian Institute of HypertensionFujianChina Department of Cardiovascular The Second Affiliated Hospital of Zhejiang University School of MedicineZhejiangChina

BACKGROUND Cardioneuroablation(CNA)has shown encouraging results in patients with vasovagal syncope(VVS).However,data on different subtypes was *** This observational study retrospectively enrolled 141 patients[mean age:40±18 years,51 males(36.2%)]with the diagnosis of *** characteristics among different types of VVS and the outcomes after CNA were *** After a mean follow-up of 4.3±1.5 years,41 patients(29.1%)experienced syncope/pre-syncope events after ***/pre-syncope recurrence significantly differed in each subtype(P=0.04).The cardioinhibitory type of VVS had the lowest recurrence rate after the procedure(n=6,16.7%),followed by mixed(n=26,30.6%)and vasodepressive(n=9,45.0%).Additionally,a significant difference was observed in the analyses of the Kaplan-Meier survival curve(P=0.02).Syncope/pre-syncope burden was significantly reduced after CNA in the vasodepressive type(Psive types with recurrent syncope/pre-syncope after CNA have a lower baseline deceleration capacity(DC)level than those without(7.4±1.0 ms vs.9.0±1.6 ms,P=0.01).Patients with DCsiONS Different subtypes exhibit different event-free *** vasodepressive type exhibited the lowest event-free rate,but those patients with DC≥8.4 ms might benefit from CNA.

关键词： syncope subtypes diagnosis