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Advances in Applied Mathematics and Mechanics 2022年第2期14卷 315-343页

作者： junpu li Zhuojia Fu Yan Gu Qing-Hua Qin School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhouHenan 450001China College of Mechanics and Materials Hohai UniversityNanjingJiangsu 211100China College of Mathematics Qingdao UniversityQingdaoShandong 266071China College of Engineering and Computer Science Australian National UniversityCanberra ACT 2601Australia

With the rapid development of computer technology,numerical simulation has become the third scientiﬁc research tool besides theoretical analysis and experi-mental *** the core of numerical simulation,constructing efﬁcient,accurate and stable numerical methods to simulate complex scientiﬁc and engineering prob-lems has become a key issue in computational *** article outlines the ap-plication of singular boundary method to the large-scale and high-frequency acoustic *** practical application,the key issue is to construct efﬁcient and accurate numerical methodology to calculate the large-scale and high-frequency soundﬁ*** article focuses on the following two research *** are how to discretize partial differential equations into more appropriate linear equations,and how to solve linear equations more efﬁ*** bottle neck problems encountered in the compu-tational acoustics are used as the technical routes,i.e.,efﬁcient solution of dense linear system composed of ill-conditioned matrix and stable simulation of wave propagation at low sampling *** article reviews recent advances in emerging appli-cations of the singular boundary method for computational *** collection can provide a reference for simulating other more complex wave propagation.

关键词： Singular boundary method origin intensity factor high-frequency acoustic problems large-scale acoustic problems Helmholtz equation

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一种模拟大规模高频声场的双层奇异边界法

力学学报 2018年第4期50卷 961-969页

作者：李珺璞陈文河海大学工程与科学数值模拟软件中心水文水资源与水利工程国家重点实验室力学与材料学院南京211100

大规模高频声场的数值模拟是一项非常有计算挑战性的课题.为了解决传统边界型离散方法由于全局支撑的满阵限制,不易应用于大规模高频声场模拟的计算瓶颈,本文提出了一种用于模拟大规模高频声场的双层奇异边界法.在该方法中,通过引入双... 详细信息

大规模高频声场的数值模拟是一项非常有计算挑战性的课题.为了解决传统边界型离散方法由于全局支撑的满阵限制,不易应用于大规模高频声场模拟的计算瓶颈,本文提出了一种用于模拟大规模高频声场的双层奇异边界法.在该方法中,通过引入双层结构,细网格上的全局支撑的满阵被转化为局部支撑的大规模稀疏矩阵,传统奇异边界法模拟大规模问题时所面临的高计算量以及过度存储需求遂得以解决.其次,双层奇异边界法仅通过粗网格评估远场作用,且独立于特定的插值核函数.相较于快速多级方法,该方法具有更强的适应性和灵活性,且多层结构使该方法具有一定的预调节作用,非常适合求解具有大规模、高秩、高条件数特点的高频波矩阵.在其后的散射球模型算例中,双层奇异边界法配置10万个节点,成功模拟了无量纲波数高达160的声散射问题.在对于人头模型的声散射特性分析中,双层奇异边界法比COMSOL软件计算速度快了约78.13%.当配置8万个节点时,双层奇异边界法成功模拟了频率高达25 kHz的工况,该频率已远远超出了人耳的听力极限.

关键词：奇异边界法高频声场计算改进双层算法无网格方法源点强度因子

走向终结的村落——山区人口流失、社会衰微与扶贫政策思考

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理论导刊 2006年第5期 41-43页

作者：李君甫北京工业大学人文社会科学学院北京100022

中国的贫困山区常住人口逐渐减少,近年来人口减少更有加快的趋势,人口的流失导致山区社会日渐衰微,山区人口的公共物品供给相对成本加大,扶贫资源的利用效率越来越低。

关键词：山区人口贫困移民

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode

一种符合Gen2标准的组证明RFID协议GIM-GP

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河南大学学报（自然科学版） 2013年第2期43卷 204-207页

作者：周星汪国安李珺璞河南大学计算机与信息工程学院河南开封475004 河南大学网络信息中心河南开封475004 河海大学大禹学院南京210098

物联网环境下RFID电子标签通常具有明显的群组特性,传统单标签认证协议已不能满足这种需求,标签的群组特性对RFID安全认证协议的设计提出了新的挑战.基于广义逆矩阵,以合理平衡安全和标签的成本为原则,设计了一个符合EPC Class1Gen2标... 详细信息

物联网环境下RFID电子标签通常具有明显的群组特性,传统单标签认证协议已不能满足这种需求,标签的群组特性对RFID安全认证协议的设计提出了新的挑战.基于广义逆矩阵,以合理平衡安全和标签的成本为原则,设计了一个符合EPC Class1Gen2标准的组证明RFID协议GIM-GP,并从安全性、匿名性、离线性、独立性和高效性五个方面对其进行分析.该协议具有处理群组标签认证的能力,为物联网环境中低成本标签的群组认证提供了一个新的解决方案.

关键词： RFID 组证明广义逆矩阵 Gen2标准认证协议

Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode *** this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery *** mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this *** leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/***,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami *** interaction of Al and F is advantageous to realize the defluoridation to some *** is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

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圆锥曲线有序多重签名方案的研究与应用

河南大学学报（自然科学版） 2013年第5期43卷 573-577页

作者：白晨希史蕊李珺璞河南大学软件学院河南开封475004 河海大学大禹学院江苏南京210098

在研究圆锥曲线密码体制的基础上,设计了一个基于双难题的圆锥曲线有序多重数字签名方案,并将其与XML数字签名技术相结合,实现了高校教务管理系统中对学生成绩的多重数字签名,以保证学生成绩信息的有效性、真实性和完整性,提高学生成绩... 详细信息

在研究圆锥曲线密码体制的基础上,设计了一个基于双难题的圆锥曲线有序多重数字签名方案,并将其与XML数字签名技术相结合,实现了高校教务管理系统中对学生成绩的多重数字签名,以保证学生成绩信息的有效性、真实性和完整性,提高学生成绩管理的工作效率,增强教务管理系统的实用性.通过系统的运行验证,以及与椭圆曲线有序多重数字签名方案比较,对学生成绩的有序多重数字签名达到预期效果,系统的安全性和运行效率得到进一步的提高.

关键词：圆锥曲线密码多重数字签名应用系统系统设计系统实现

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盾构管片接头刚度衰减系数(ACS)的影响

地下空间与工程学报 2018年第3期14卷 683-687页

作者：董新平朱磊李宗艺李君普郑州大学交通运输工程系郑州450002

以盾构隧道衬砌三环原型加载破坏试验为基础,通过严格按照足尺试验尺寸、试验条件建立分析模型并消除环间作用的方法建立了单环加载破坏分析模型,着重就某局部管片接头转动刚度衰减对整环内力(弯矩)的影响进行分析,研究表明:(1)在盾构... 详细信息

以盾构隧道衬砌三环原型加载破坏试验为基础,通过严格按照足尺试验尺寸、试验条件建立分析模型并消除环间作用的方法建立了单环加载破坏分析模型,着重就某局部管片接头转动刚度衰减对整环内力(弯矩)的影响进行分析,研究表明:(1)在盾构隧道管片整环破坏历程中,管片接头转动刚度的变化历程可通过转动刚度衰减系数这一特征变量进行追踪;(2)特定位置管片接头转动刚度衰减时,可导致其他位置管片弯矩发生增加或降低,且增减幅度并不一致;(3)在整环外加荷载增量保持不变的条件下,特定位置管片接头转动刚度的衰减(破坏)可导致管片环其它位置的弯矩迅速增加,从而引起或加速整环管片的破坏。

关键词：隧道工程盾构管片接头刚度衰减系数

Whole-genome Sequencing Reveals Autooctoploidy in Chinese Sturgeon and Its Evolutionary Trajectories

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 51-65页

作者： Binzhong Wang Bin Wu Xueqing liu Yacheng Hu Yao Ming Mingzhou Bai Juanjuan liu Kan Xiao Qingkai Zeng Jing Yang Hongqi Wang Baifu Guo Chun Tan Zixuan Hu Xun Zhao Yanhong li Zhen Yue junpu Mei Wei Jiang Yuanjin Yang Zhiyuan li Yong Gao Lei Chen Jianbo Jian Hejun Du Hubei Key Laboratory of Three Gorges Project for Conservation of Fishes Yichang 443100China Chinese Sturgeon Research Institute China Three Gorges CorporationYichang 443100China Yangtze River Biodiversity Research Center China Three Gorges CorporationWuhan 430014China BGI-Shenzhen Shenzhen 518083China BGI Genomics BGI-ShenzhenShenzhen 518083China Department of Biotechnology and Biomedicine Technical University of DenmarkLyngby 2800Denmark River Basin Complex Administration Center China Three Gorges CorporationYichang 443100China BGI-Sanya BGI-ShenzhenSanya 572025China Yangtze Eco-Environment Engineering Research Center China Three Gorges CorporationBeijing 100038China

The order Acipenseriformes,which includes sturgeons and paddlefishes,represents“living fossils”with complex genomes that are good models for understanding whole-genome duplication(WGD)and ploidy evolution in ***,we sequenced and assembled the first high-quality chromosome-level genome for the complex octoploid Acipenser sinensis(Chinese sturgeon),a critically endangered species that also represents a poorly understood ploidy group in *** results show that *** is a complex autooctoploid species containing four kinds of octovalents(8n),a hexavalent(6n),two tetravalents(4n),and a divalent(2n).An analysis taking into account delayed rediploidization reveals that the octoploid genome composition of Chinese sturgeon results from two rounds of homologous WGDs,and further provides insights into the timing of its ploidy *** study provides the first octoploid genome resource of Acipenseriformes for understanding ploidy compositions and evolutionary trajectories of polyploid fishes.

关键词： Chinese sturgeon Whole-genome sequencing Autooctoploid Polyploidization and diploidization Whole-genome duplication

SEI/dead li-turning capacity loss for high-performance anode-free solid-state lithium batteries

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Journal of Energy Chemistry 2024年第9期96卷 145-152页

作者： Qianwen Yin Tianyu li Hongzhang Zhang Guiming Zhong Xiaofei Yang Xianfeng li Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Long-Duration and Large-Scale Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Laboratory of Advanced Spectro-Electrochemistry and lithium-Ion Batteries Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal ***,the unclear mechanism for the fast capacity decay in AF-SSLBs,either determined by dead li or solid electrolyte interface(SEI),limits the proposal of effective strategies to prolong cycling *** clarify the underlying mechanism,herein,the evolution of SEI and dead li is quantitatively analyzed by a solid-state nuclear magnetic resonance(ss-NMR)technology in a typical liPF6-based polymer *** results show that the initial capacity loss is attributed to the formation of SEI,while the dead li dominates the following capacity loss and the growth rate is 0.141 mA h cm^(−2)cycle−*** reduce the active li loss,the combination of inorganic-rich SEI and self-healing electrostatic shield effect is proposed to improve the reversibility of li deposition/dissolution behavior,which reduces the capacity loss rate for the initial SEI and following dead li generation by 2.3 and 20.1 folds,*** a result,the initial Coulombic efficiency(ICE)and stable CE increase by 15.1%and 15.3%in li-Cu cells,which guides the rational design of high-performance AF-SSLBs.

关键词： Solid-state lithium batteries Solid-state NMR Anode-free SEI Dead li