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Design,preparation,and characterization of a novel ZnO/CuO/Al energetic diode with dual functionality:Logic and destruction

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Defence Technology（防务技术） 2024年第4期34卷 57-68页

作者： Jialu Yang Jiaheng hu Yinghua Ye Jianbing Xu Yan hu Ruiqi Shen School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing 210094China Institute of Space Propulsion Nanjing University of Science and TechnologyNanjing 210094China

Self-destructing chips have promising applications for securing *** paper proposes a new concept of energetic diodes for the first time,which can be used for self-destructive chips.A simple two-step electrochemical deposition method is used to prepare ZnO/CuO/Al energetic diode,in which N-type ZnO and P-type CuO are constricted to a PN *** paper comprehensively discusses the material properties,morphology,semiconductor characteristics,and exploding performances of the energetic *** results show that the energetic diode has typical rectification with a turn-on voltage of about 1.78 V and a reverse leakage current of about 3×10^(-4)*** a constant voltage of 70 V loads to the energetic diode in the forward direction for about 0.14 s or 55 V loads in the reverse direction for about 0.17 s,the loaded power can excite the energetic diode exploding and the current rises to about100 *** to the unique performance of the energetic diode,it has a double function of rectification and *** energetic diode can be used as a logic element in the normal chip to complete the regular operation,and it can release energy to destroy the chip accurately.

关键词： Energetic diode ZnO—CuO—Al thermite ZnO/CuO PN junction Electrical explosion performance Self-destructing chips

Impact of Polymer Matrix on Polymer Mechanochromism from Excited State Intramolecular Proton Transfer

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Chinese Journal of Chemistry 2024年第6期42卷 611-616页

作者： Yu Wu Xin Cheng huan hu Shui hu Zhimin Ma Zhiyong Ma Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing100029 China Center of Advanced Elastomer Materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China College of Engineering Peking UniversityBeijing100871 China

Mechanochromic polymers based on non-covalent changes have attracted much attention ***,we report the impact of inter/intramolecular hydrogen bonds on polymer mechanochromism from the excited state intramolecular proton transfer (ESIPT) ***-NH2-OH and PhMz=2A are designed and obtained by simple and high-yield synthesis,and are connected into polyurethane and poly(methyl acrylate-co-2-ethylhexyl acrylate),*** the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hydrogen bonds that interrupt the ESIPT reactions but the PhMz=2A@PMA-2-EA sample expresses cyan fluorescence belonging to the excited keto form (K*) emission,implying that the intramolecular hydrogen bonds ***,under stretching,external force can tune the emission of the PhMz=2A@PMA-2-EA sample from K* to E* *** external force can putatively still promote a bond rotation,ESIPT reactions remain equivalently interrupted in both the relaxed and stressed states in a hydrogen-bond donating *** calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/***,PhMz-NH2-OH@PU and PhMz=2A@PMA-2-EA showed disparate initial ESIPT states and further different responses/sensitivity to *** study reports a novel and efficient strategy for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Polymer mechanochromism Excited state intramolecular proton transfer Hydrogen bonding Supramolecular chemistry Elastomers

Allosteric DNAzyme-based encoder for molecular information transfer

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Chinese Chemical Letters 2024年第7期35卷 235-241页

作者： Minghao hu Tianci Xie Yuqiang hu Longjie Li Ting Wang tongbo Wu School of Pharmacy Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Oncology Tongji Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China GI Cancer Research Institute Tongji HospitalHuazhong University of Science and TechnologyWuhan 430030China School of Life Science and Technology Wuhan Polytechnic UniversityWuhan 430023China State Key Laboratory of Bioelectronics National Demonstration Center for Experimental Biomedical Engineering EducationSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China

Dynamic DNA nanotechnology plays a significant role in nanomedicine and information science due to its high programmability based on Watson-Crick base pairing and nanoscale *** DNA machines and networks have been widely used in various fields,including molecular imaging,biosensors,drug delivery,information processing,and logic *** serve as crucial components for information compilation and transfer,allowing the conversion of information from diverse application scenarios into a format recognized and applied by DNA ***,there are only a few encoder designs with DNA ***,the molecular priority encoder is hardly *** this study,we introduce allosteric DNAzyme-based encoders for information *** design of the allosteric domain and the recognition arm allows the input and output to be independent of each other and freely *** pre-packaged mode design achieves uniformity of baseline dynamics and dynamics *** also integrated non-nucleic acid molecules into the encoder through the aptamer design of the allosteric ***,we developed the 2^(n)-n encoder and the EndoⅣ-assisted priority encoder inspired by immunoglobulin's molecular structure and effector *** our knowledge,the proposed encoder is the first enzyme-free DNA encoder with DNA output,and the priority encoder is the first molecular priority encoder in the DNA reaction *** encoders avoid complex operations on a single molecule,and their simple structure facilitates their application in complex DNA circuits and biological scenarios.

关键词： DNAzyme Encoder Nucleic acids DNA circuit DNA strand displacement Dynamic DNA nanotechnology

Fracture mechanism of inclusions in thick plate center under tensile loading

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1196-1209页

作者： Lei hu Li-qin Zhang Feng hu Guo-hong Zhang Kuan Zheng Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081HubeiChina Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081HubeiChina Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081HubeiChina

Segregation of solute atoms in the center of thick plates of the tempered steel can cause an inhomogeneous structural transformation and generate micron-sized inclusions,which leads to lamellar tearing of thick plate and decreases the plasticity and *** formation and fragmentation mechanisms of micron-sized inclusions,like MnS and(Nb,Ti)C,in the center of thick plates were investigated by using thermodynamic calculations,finite element simulations,and electron backscatter diffraction characterization *** results show that micron-sized inclusions nucleate and grow in the liquid phase,and under tensile loading,they exhibit three fragmentation *** local stress during the fragmentation of inclusions is lower than the critical fracture stress of adjacent grains,and phase boundaries can effectively impede crack propagation into the *** existence of a low proportion of high-angle grain boundaries(58.1%)and high Kernel average misorientation value(0.534°)in the segregation band promotes inclusions fragmentation and crack *** difference in crack initiation and propagation direction caused by the morphology of inclusions and physical properties,as well as different matrix arrest abilities,is the main reasons for the diversity of inclusion fragmentation.

关键词： Thick plate Inclusion Finite element simulation Critical fracture stress Fracture mechanism

世界高水平乒乓球运动员马龙与樊振东“关键分”技战术运用效果比较研究

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体育科技文献通报 2024年第5期32卷 52-56页

作者：胡涛兰彤武汉体育学院湖北武汉430079

世界高水平乒乓球运动员竞技实力相当,往往容易在一局比赛中进入到“关键分”。运动员在比赛中对“关键分”的处理会影响每局甚至是整场比赛结果的走势,所以对运动员“关键分”进行研究十分有必要。本文采用文献资料法、录像观察法、四... 详细信息

世界高水平乒乓球运动员竞技实力相当,往往容易在一局比赛中进入到“关键分”。运动员在比赛中对“关键分”的处理会影响每局甚至是整场比赛结果的走势,所以对运动员“关键分”进行研究十分有必要。本文采用文献资料法、录像观察法、四段指标评估法、数理统计法、对比分析法,对马龙与樊振东“关键分”技战术运用效果进行比较分析,以期为其他运动员提高“关键分”处理能力提供参考。结果显示:马龙与樊振东“关键分”时的发抢段、接抢段及相持II段表现出卓越的得分效果;2人在发抢段“关键分”的主要得分手段为发球抢攻;马龙接抢段“关键分”偏向于稳健,樊振东单板质量突出,双方在2-4板战术组合方面善于突破对方反手位区域;相持I段和相持II段起始和结束位置都集中在双方的左半台区域。

关键词：马龙樊振东乒乓球比赛关键分技战术运用效果

ZIFs材料对Fe/N/C催化剂氧还原性能的影响

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材料导报 2024年第10期38卷 45-51页

作者：宋冬梅郑秋燕潘廷仙胡长刚同鑫田娟贵州师范大学化学与材料科学学院贵阳550001 贵州省功能材料化学重点实验室贵阳550001

过渡金属/氮/碳(M/N/C)催化剂是替代铂基催化剂用于氧还原反应(ORR)的理想材料。沸石咪唑骨架(ZIFs)材料结合了无机沸石的高稳定性和MOFs材料的高比表面积、高孔隙率及可调孔结构等特点,是制备M/N/C催化剂的优良前驱体。本工作以FeSO4·... 详细信息

过渡金属/氮/碳(M/N/C)催化剂是替代铂基催化剂用于氧还原反应(ORR)的理想材料。沸石咪唑骨架(ZIFs)材料结合了无机沸石的高稳定性和MOFs材料的高比表面积、高孔隙率及可调孔结构等特点,是制备M/N/C催化剂的优良前驱体。本工作以FeSO4·7H2O为铁源,1,10-菲啰啉为氮源,探究不同ZIFs材料对FeN/C-Zx催化剂ORR性能的影响。通过X射线衍射、比表面积和孔径分布测试、透射电子显微镜等对催化剂进行结构表征,使用线性扫描伏安法对催化剂ORR催化活性进行测试。结果表明:FeN/C-Z8催化剂表现出最佳的ORR活性,具有较小的Tafel斜率(64.98 mV/dec)且反应过程是近四电子过程;在经过25000次循环后,FeN/C-Z8催化剂的半波电位仅有20 mV的负移,表现出良好的稳定性。FeN/C-Z8催化剂中存在的Fe3C化合物可有效提高催化剂的催化性能;Zn2+在碳化过程中挥发使FeN/C-Z8催化剂具有较高比表面积(550.09 m2/g)、孔体积(1.36 cm3/g)及丰富的微孔、介孔结构,并促进了过渡金属在ZIFs材料上的均匀分布,使FeN/C-Z8催化剂颗粒较小、分散均匀,这是该催化剂表现出较好的ORR催化性能的可能原因。

关键词：氧还原反应非贵金属催化剂沸石咪唑骨架 FeN掺杂

Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang Zhong Jiang Pei-Da hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

Trajectory tracking guidance of interceptor via prescribed performance integral sliding mode with neural network disturbance observer

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Defence Technology（防务技术） 2024年第2期32卷 412-429页

作者： Wenxue Chen Yudong hu Changsheng Gao Ruoming An School of Astronautics Harbin Institute of TechnologyHarbin 150001China

This paper investigates interception missiles’trajectory tracking guidance problem under wind field and external disturbances in the boost ***,the velocity control in such trajectory tracking guidance systems of missiles is *** our contribution,the velocity control channel is designed to deal with the intractable velocity problem and improve tracking *** global prescribed performance function,which guarantees the tracking error within the set range and the global convergence of the tracking guidance system,is first proposed based on the traditional ***,a tracking guidance strategy is derived using the integral sliding mode control techniques to make the sliding manifold and tracking errors converge to zero and avoid ***,an improved switching control law is introduced into the designed tracking guidance algorithm to deal with the chattering problem.A back propagation neural network(BPNN)extended state observer(BPNNESO)is employed in the inner loop to identify *** obtained results indicate that the proposed tracking guidance approach achieves the trajectory tracking guidance objective without and with disturbances and outperforms the existing tracking guidance schemes with the lowest tracking errors,convergence times,and overshoots.

关键词： BP network neural Integral sliding mode control(ISMC) Missile defense Prescribed performance function(PPF) State observer Tracking guidance system

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基于自动化私有协议识别的挖矿流量检测

北京航空航天大学学报 2024年第7期50卷 2304-2313页

作者：童瑞谦胡夏南刘优然秦研张宁王强西安电子科技大学网络与信息安全学院西安710071 中国科学院大学网络空间安全学院北京100049 中国科学院信息工程研究所北京100093

面向虚拟货币挖矿过程中私有协议流量检测识别需求,提出面向未知挖矿行为通信协议流量的自动化识别方法。改进N-gram报文格式分割算法和字典树正则表达式生成算法,实现私有协议特征签名自动化生成,对明文通信的挖矿流量进行精确匹配;基... 详细信息

面向虚拟货币挖矿过程中私有协议流量检测识别需求,提出面向未知挖矿行为通信协议流量的自动化识别方法。改进N-gram报文格式分割算法和字典树正则表达式生成算法,实现私有协议特征签名自动化生成,对明文通信的挖矿流量进行精确匹配;基于经典加密流量分类模型,改进基于流交互特征的流量分析方法,实现轻量级的挖矿行为识别模型,对加密通信的挖矿流量进行实时检测。测试结果表明:所提方法生成的挖矿通信协议特征签名可覆盖当前3种主流明文挖矿流量,在实网验证过程中可达到0.996的识别精确率和0.985的召回率。

关键词：虚拟货币挖矿流量私有协议自动化正则签名加密流量识别