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Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate

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Defence Technology（防务技术） 2024年第2期32卷 222-231页

作者： Haotian Jian Guoqiang zheng Lejian Chen zheng ning Guofu Yin Peng Zhu Ruiqi Shen School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing University of Science and TechnologyNanjing 210094China Anhui Province Key Laboratory of Microsystem the 43rd Research Institute of CETCHefei 230088China Science and Technology on Applied Physical and Chemistry Laboratory Shanxi Applied Physics and Chemistry Research Institute Xi'an 710061China

Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting *** solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting *** oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma *** results of the electric characteristics and the impact pressure were inconsistent with ignition *** only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating ***,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this *** HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric *** longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.

关键词： Exploding foil initiator PDV Plasma spectrum Ignition mechanism Boron potassium nitrate

Intestinal malrotation complicated with gastric cancer: A case report

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World Journal of Clinical Cases 2024年第1期12卷 210-216页

作者： Xiang-Hao Jia Shuai Kong Xin-Xin Gao Bi-Cong Cong Chun-ning zheng School of Clinical Medicine Weifang Medical UniversityWeifang 261053Shandong ProvinceChina Department of Gastrointestinal Surgery Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina

BACKGROUND Intestinal malrotation is a congenital defect of embryonic development caused by various teratogenic *** this condition,the intestinal tube,along with the superior mesenteric artery serving as the axis for the counterclockwise movement,is incomplete or abnormally rotated due to incomplete attachment of the mesentery and abnormal intestinal tube *** a case is usually asymp-tomatic and thus difficult to ***,similar variant malformations are only found during an operation required for other abdominal *** SUMMARY An elderly male patient was admitted to the hospital due to gastric *** abdominal computed tomography(CT)scan with contrast revealed that the ascending and descending colon were parallel on the right side of the abdominal cavity,while the sigmoid colon extended into the right iliac fossa,allowing the diagnosis of congenital midgut *** thorough preoperative preparation,the patient underwent laparoscopic radical gastrectomy to treat his gastric ***,an exploration of the abdominal cavity uncovered the absence of the transverse *** distal colon at the hepatic flexure,along with the ascending colon,extended into the right iliac fossa,where it continued as the sigmoid *** planned,the laparoscopic radical gastrectomy was perform-ed,and the patient was discharged from the hospital 7 d after the *** Asymptomatic intestinal malrotation is best detected by CT,requiring no treatment but possibly interfering with the treatment of other diseases.

关键词： Intestinal malrotation Congenital malformation Gastric cancer Abdominal

Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-Cheng Gu Zhao-Jing Han Ze-Yu Chen Zhao-Xuan Li Sheng-Bao Xia zheng-ning Li Hua Jin Wei-Wei Xu Xing-Jun Liu Shenzhen Research Institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods

晚明颍州的军籍士绅与地方社会——兼论卫所的“民化”

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安徽史学 2024年第3期 134-142页

作者：郑宁上海师范大学人文学院上海200234

在晚明颍州士绅社会的形成过程中,构成士绅核心的科举精英主要来自颍州卫军户,地方豪族也以军户家族为主。军籍士子的科举成就得益于卫所体制的支持,获得功名的军籍士绅与世袭武官紧密联系,维护卫所与军户的利益,形成了有利于军户的正... 详细信息

在晚明颍州士绅社会的形成过程中,构成士绅核心的科举精英主要来自颍州卫军户,地方豪族也以军户家族为主。军籍士子的科举成就得益于卫所体制的支持,获得功名的军籍士绅与世袭武官紧密联系,维护卫所与军户的利益,形成了有利于军户的正向循环。在“民化”的过程中,卫所通过培育和支持军籍士绅,既推动了士绅社会的建构,也增强了军户的势力。凭借社会优势地位,军籍士绅成为颍州基层社会的主导力量,主动引领地方社会的塑造,将卫所的特质深刻融入地方。颍州的案例提示,明代卫所的“民化”存在地域差异,军户融入地方的路径并不单一。在社会环境、政策制度、教育资源等因素的作用下,卫所的“民化”不只是被动融入,也可能成为改造地方社会的重要契机。

关键词：颍州士绅卫所军户

Ultratough Yet Dynamic Crystalline Poly(thiourethane)Network Directly from Low Viscosity Precursors

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CCS Chemistry 2024年第3期6卷 682-692页

作者： Haijun Feng Yi Sheng Guancong Chen Binjie Jin Zizheng Fang Bo Yang Xiaorui Zhou Wenxuan Wu Tao Xie ning zheng State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058 Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310027

Thermosets based on direct curing of multifunctional monomers offer processing flexibility that thermoplastics cannot ***,this type of thermoset is typically amorphous since it is difficult to meet the stringent requirement of long-range molecular regularity for ***,we report here a crystallizable poly(thiourethane)thermoset synthesized directly from the curing of low-viscosity liquid precursors that does not employ any *** crystalline nature results in superior toughness,comparable to commercial high-density polyethylene,in sharp contrast to the brittleness of the typical,rigid,glassy thermoset *** that,the network polymer exhibits shape-memory behavior in which the crystalline transition is utilized for temporary shape fixing/recovery whereas the dynamic thiourethane bonds can be activated for bond exchange as a mechanism for complex shape *** with these combined features represent attractive options for demanding engineering applications due to their high performance and multifunctinality.

关键词： thermosets crystalline polymer thiourethane thermadapt

面向冲突化解的双线交汇区段列车编队双层优化模型

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同济大学学报（自然科学版） 2024年第1期52卷 18-26页

作者：宁正张雷何积丰同济大学上海市轨道交通结构耐久与系统安全重点实验室上海201804 同济大学道路与交通工程教育部重点实验室上海201804

针对虚拟编组列车在双线交汇区段上面临的冲突与通过效率问题,提出了多种速度组编协调策略。将列车汇入时间、次序、编队组合和速度序列决策集成在双层优化模型中,上层模型优化通过效率,下层模型提高编队质量;设计双层嵌套粒子群算法,... 详细信息

针对虚拟编组列车在双线交汇区段上面临的冲突与通过效率问题,提出了多种速度组编协调策略。将列车汇入时间、次序、编队组合和速度序列决策集成在双层优化模型中,上层模型优化通过效率,下层模型提高编队质量;设计双层嵌套粒子群算法,将汇入时间作为双层模型的中间交互变量,使列车群能根据环境需求收敛于不同队形。仿真结果表明,加入协调速度优化可以提高组编过程效率,双层编队模型可以在确保编队结构稳定性和均衡性的同时提高既有线路通过率。

关键词：虚拟编组列车编队方法双层优化模型冲突化解编队协调

Macroscopic,artificial active matter

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National Science Open 2024年第4期3卷 106-141页

作者： Luhui ning Hongwei Zhu Jihua Yang Qun Zhang Peng Liu Ran Ni ning zheng Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum-BeijingBeijing 102249China Basic Research Center for Energy Interdisciplinary College of ScienceChina University of Petroleum-BeijingBeijing 102249China School of Physical Science and Technology Key Laboratory of Magnetism and Magnetic Materials for Higher Education in lnner Mongolia Autonomous RegionBaotou Teachers’CollegeBaotou 014030China School of Physics Beijing Institute of TechnologyBeijing 100081China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological UniversitySingapore 637459Singapore

Artificial active matters on a macroscopic scale,including vibrating particles,robots,and camphor boats,have attracted increasing attentions due to their uniform properties,rich and easily controllable parameters,convenient observation,and the independence of biochemical processes from physical processes,especially providing these unique advantages for researching the collective behaviors under strong confinement and crowded *** this review,we present an overview of motion models,mechanisms,and dynamic characteristics of various active particles,both in free and complex ***,we delve into the collective behaviors of“dry”active matter,covering structural and dynamic properties observed in experiments and theoretical *** summarize the impact of hydrodynamic interactions on the dynamics and structures of these active particles within hydrodynamic ***,we discuss emerging opportunities and challenges for future advancement of macroscopic artificial active matter.

关键词： active particles structure dynamic properties dry active matter hydrodynamic environment

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驱动温度可调的依序自滚动液晶弹性体

高分子学报 2024年第5期55卷 614-623页

作者：周筱睿杨博郑宁浙江大学化学工程与生物工程学院化学工程联合国家重点实验室杭州310058

传统的自驱动液晶弹性体,受限于单一的材料化学设计,仅能在特定条件(或温度范围)下实现自主运动.为了解决这一限制,本研究基于扭曲带状的自驱动液晶弹性体,通过调节网络的交联密度和引入非液晶共聚单体的方法,成功实现了对自驱动液晶弹... 详细信息

传统的自驱动液晶弹性体,受限于单一的材料化学设计,仅能在特定条件(或温度范围)下实现自主运动.为了解决这一限制,本研究基于扭曲带状的自驱动液晶弹性体,通过调节网络的交联密度和引入非液晶共聚单体的方法,成功实现了对自驱动液晶弹性体工作温度的精确设计.在进一步优化材料的驱动性能和力学性能后,获得了工作温度范围不同的自驱动液晶弹性体,分别实现了不同软体驱动器在升温和降温过程中的按需依次滚动.这种可调工作温度的自驱动液晶弹性体将显著拓展软机器人材料的设计应用领域.

关键词：液晶弹性体软体驱动器自主运动

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面向城轨云平台边界安全防护的动态信任管理方法

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同济大学学报（自然科学版） 2024年第2期52卷 157-165,F0002页

作者：张雷徐倩何积丰曾小清宁正同济大学交通运输工程学院上海201804 同济大学上海自主智能无人系统科学中心上海201810

针对城轨云平台边界数量多、边界安全防护薄弱的问题,分析了城轨云与工业控制网络协同交互过程,提出了一种面向城轨云平台边界安全防护的动态信任管理方法,包括异常行为识别、信任评估、信任更新、基于信任值的动态访问控制。根据城轨... 详细信息

针对城轨云平台边界数量多、边界安全防护薄弱的问题,分析了城轨云与工业控制网络协同交互过程,提出了一种面向城轨云平台边界安全防护的动态信任管理方法,包括异常行为识别、信任评估、信任更新、基于信任值的动态访问控制。根据城轨云的综合监控系统网络拓扑,分析了未经授权控制指令、违规控制指令、干扰正常控制指令三类异常行为。结果表明,所提出的动态信任管理方法能够有效抵御恶意节点发起的异常行为;对于不同节点、不同异常行为的信任值变化不同;符合“缓升快降”的规则,能够保障城轨云平台细粒度的边界安全防护。

关键词：信任管理城轨云边界安全防护异常控制指令