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Multiple magnetic topologies in flux transfer events: THEMIS measurements

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Science China(Technological Sciences) 2016年第8期59卷 1283-1293页

作者： lV leiQi pu Zuyin XIE lun School of Earth and Space Science Peking University Beijing 100871 China PKU/UClA Joint Research Institute in Science and Engineering Peking University Beijing 100871 China

Flux transfer events （FTEs） are local transient magnetic reconnections at the magnetopause （MP） that provide channels for transport of solar wind energy and plasma into the magnetosphere （MSP）. All current theoretical models suggest that FTEs are open-flux ropes; however, global simulations show that they contain both open and closed magnetic fields. To clarify this to- pology, we analyzed 441 events observed by THEMIS and investigated their magnetic topologies. Only one type of open field line was detected in most magnetosheath （MSH） FTEs, independent of the polarity of the Bn bipolar signatures. Newly formed MSH field lines were also observed. In the all MP boundary layers FTEs and most MSP FTEs, multiple types of topologies were observed, irrelevant to the Bn bipolar polarity. Closed field lines were found in all MP boundary layers and MSP FTEs. Meanwhile very few boundary FTEs contained the newly formed MSH flux. In some situations, only closed field lines were seen in MSP FTEs, which are referred to as the fossil FTEs. These results, which largely differ from the traditional view, demonstrate the existence of complex magnetic topologies in FTEs. Based on these results, we propose a new 3D FTE picture to modify the current FTE models.

关键词： flux transfer events magnetic flux rope magnetic field topology magnetopause

Triboelectric nanogenerators as wearable power sources and self-powered sensors

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National Science Review 2023年第1期10卷 28-48页

作者： Xiong pu Chi Zhang Zhong lin Wang CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and Sensor Beijing Institute of Nanoenergy and NanosystemsChinese Academy of Sciences School of Nanoscience and Technology University of Chinese Academy of Sciences School of Materials Science and Engineering College of EngineeringGeorgia Institute of Technology

Smart we arable technologies are augmenting human bodies beyond our biological capabilities in communication,healthcare and *** supply and information acquisition are essential for wearable electronics,whereas the increasing demands in multifunction are raising the requirements for energy and sensor *** triboelectric nanogenerator(TENG),proven to be able to convert various mechanical energies into electricity,can fulfill either of these two functions and therefore has drawn extensive attention and research efforts *** everyday life of a human body produces considerable mechanical energies and,in the meantime,the human body communicates mainly through mechanical signals,such as sound,body gestures and muscle ***,the TENG has been intensively studied to serve as either wearable sources or wearable self-powered ***,the recent finding on the fundamental understanding of TENGs is revisited briefly,followed by a summary of recent advancements in TENG-based wearable power sources and self-powered *** challenges and prospects of this area are given as well.

关键词： triboelectric nanogenerators power sources self-powered sensors wearable electronics

Knowledge-oriented modeling for influencing factors of battle damage in military industrial logistics:An integrated method

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Defence Technology（防务技术） 2020年第3期16卷 571-587页

作者： Xiong li Xiao-dong Zhao Wei pu Military Exercise and Training Center Army Academy of Armored ForcesBeijing 100072China

Modeling influencing factors of battle damage is one of essential works in implementing military industrial logistics simulation to explore battle damage laws ***,one of key challenges in designing the simulation system could be how to reasonably determine simulation model input and build a bridge to link battle damage model and battle damage laws *** this paper,we propose a novel knowledge-oriented modeling method for influencing factors of battle damage in military industrial logistics,integrating conceptual analysis,conceptual modeling,quantitative modeling and simulation *** conceptualize influencing factors of battle damage by using the principle of hierarchical decomposition,thus classifying the related battle damage knowledge ***,we construct the conceptual model of influencing factors of battle damage by using Entity-Relations hip approach,thus describing their interactions ***,we extract the important influencing factors by using social network analysis,thus evaluating their importance quantitatively and further clarifying the elements of ***,we develop an agent-based military industry logistics simulation system by taking the modeling results on influencing factors of battle damage as simulation model input,and obtain simulation model output,i.e.,new battle damage laws knowledge,thus verifying feasibility and effectiveness of the proposed *** results show that this method can be used to support human decision-making and action.

关键词： Battle damage Industrial logistics Entity-relationship approach Social network analysis Agent-based simulation

Divalent anion intercalation and etching-hydrolysis strategies to construct ultra-stable electrodes for seawater splitting

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Science China Chemistry 2024年第2期67卷 687-695页

作者： Jiajia lu yang liu Han-pu liang Key laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao266101China Henan Provincial Key laboratory of Nanocomposites and Applications Institute of Nano-Structured Functional MaterialsHuanghe Science and Technology CollegeZhengzhou450006China School of Materials Science and Engineering Henan Normal UniversityXinxiang453007China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Shandong Energy Institute Qingdao266101China

Developing stable electrodes for seawater splitting remains a great challenge due to the detachment of catalysts at a large operating current and severe anode corrosion caused by ***,divalent anion intercalation and etching-hydrolysis strategies are deployed to synthesize the ultra-stable anode,dendritic Fe(OH)_(3) grown on Ni(SO_4)_(0.3)(OH)_(1.4)–Ni(OH)_(2).Experimental results reveal that the anode exhibits good activity and excellent stability in alkaline simulated *** 500 h,the current density operated at 1.72 V remains 99.5%,about 210 m A cm^(-2).The outstanding stability originates from the etchinghydrolysis strategy,which strengthens the interaction between the catalyst and the carrier and retards thus the detachment of catalysts at a large current ***,theoretical simulations confirm that the intercalated divalent anions,such as SO_4^(2-) and CO_(3)^(2-),can weaken the adsorption strength of chlorine on the surface of catalysts and hinder the coupling and hybridization between chlorine and nickel,which slows down the anode corrosion and improves catalytic ***,the twoelectrode system shows the remarkable 95.1% energy efficiency at 2,000 A m-2and outstanding stability in 6 mol l^(-1) KOH +seawater at 80 ℃.

关键词： seawater splitting stability divalent anion intercalation etching-hydrolysis

Recommendations on legislative and regulatory framework and regulatory body of nuclear security in China

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Nuclear Science and Techniques 2007年第5期18卷 307-310页

作者： pu Jilong lI Xiaoyan China Guangdong Nuclear Power Holding Co. ltd. Shenzhen 518031 China

This paper describes the definition of nuclear security that has been changing from the cold war age to the post-911 period, and clarifies the close relationship and yet a clear distinction between nuclear security, nuclear safety and nuclear safeguard. Based on analyses of the current state of nuclear security activities in China as well as the requirements and the law infrastructure, a legislative and regulatory framework of nuclear security and the mandate of a regulatory body in China are recommended.

关键词：核安全立法反应堆安全管理

Preparation of fine copper powders and their application in BME-MlCC

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Journal of University of Science and Technology Beijing 2006年第3期13卷 250-255页

作者： Songping Wu Haoli Qin pu li College of Chemistry South China University of Technology Guangzhou 510641 China

The preparation of fine copper powders by chemical reduction method was investigated. The reaction of [Cu（NH3）4]2^＋ complex with hydrazine hydrate gives spherical monodispersed fine copper powders. The spherical copper powder with a uniform size of 3.5 ± 0.5 μtm was processed to obtain flake copper powder having a uniform size of 8-10 μm, excellent dispersibility and uniform shape. The spherical copper powder of 2.5 ±0.3 μm in size, flake copper, glass frit and vehicle were mixed to prepare copper paste, which was fired in 910-920℃ to obtain BME-MlCC （base metal multilayer ceramic capacitor） with a dense surface of end termination, high adhesion and qualified electrical behavior. Polarized light photo and SEM were employed to observe the copper end termination of BME-MlCC. The rough interface from the interracial reaction between glass and chip gives high adhesion.

关键词： spherical copper powder flake copper powder chemical reduction BME-MlCC

A New lizard(lepidosauria:Squamata) from the Upper Cretaceous of Henan,China

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Acta Geologica Sinica(English Edition) 2014年第4期88卷 1041-1050页

作者： XU li WU Xiaochun lü Junchang JIA Songhai ZHANG Jiming pu Hanyong ZHANG Xingliao Henan Geological Museum Canadian Museum of Nature Institute of Geology Chinese Academy of Geological Sciences Key lab of Stratigraphy and Paleontology Ministry of Land and Resources of China

Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in luanehuan County, Henan Province. It is the second representative of lizards known from luanchuan and adds a new member to the luanchuan Fauna. F. luanchuanensis is a small-sized lizard and systematically assigned to the Polyglyphanodontidae of the Teiioidea because of the presence of a caniniform tooth and an elongate posterior process of the postorbital. It is distinctive in that the heterodont dentition bears 19 teeth in both the upper and lower jaws, the 3^rd maxillary tooth is large and caniniform, the post-caniniform teeth in maxilla and those posterior to the 3^rd dentary tooth are chisel-like in lateral view, the prefrontal possesses a fossa on its lateral surface, the postorbital with an extremely elongate posterior process and the well-developed retroarticular process has a deep fossa on its dorsal surface. In phylogeny, our analysis suggests a close relationship of Funiusaurus to the large-sized Tianyusaurus from the same basin within the Tuberocephalosaurinae. The discovery of Funiusaurus is significant in confirming the status of the Tuberocephalosaurinae, which includes a group of the Asian members of the Polyglyphanodontidae only.

关键词： Squamata Funiusaurus Qiupa Formation late Cretaceous Henan

An approach for predicting digital material consumption in electronic warfare

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Defence Technology（防务技术） 2020年第1期16卷 263-273页

作者： Xiong li Xiao-dong Zhao Wei pu Military Exercise and Training Center Army Academy of Armored ForcesBeijing 100072China

Electronic warfare is a modern combat mode,in which predicting digital material consumption is a key for material requirements planning(MRP).In this paper,we introduce an insensitive loss function(ε) and propose a ε-SVR-based prediction ***,we quantify values of influencing factors of digital equipments in electronic warfare and a small-sample data on real consumption to form a real combat data set,and preprocess it to construct the sample ***,we establish the ε-SVR-based prediction model based on "wartime influencing factors-material consumption" and perform model *** case study,we give 8 historical battle events with battle damage data and predict 3 representative kinds of digital materials by using the proposed *** results illustrate its higher accuracy and more convenience compared with other current *** data acquisition controller prediction as an example,our model has better prediction performance(RMSE=0.575 7,MAPE(%)=12.037 6 and R^2=0.996 0) compared with BP neural network model(RMSE=1.272 9,MAPE(%)=23.577 5 and R^2=0.980 3) and GM(1,1) model(RMSE=2.095 0,MAPE(%)=24.188 0 and R^2=0.946 6).The fact shows that the approach can be used to support decision-making for MRP in electronic warfare.

关键词： Electronic warfare Support vector regression(SVR) Prediction model Decision-making

Objective triangle functors

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Science China Mathematics 2015年第2期58卷 221-232页

作者： RINGEl Claus Michael ZHANG pu Department of Mathematics Shanghai Jiao Tong University Department of Mathematics King Abdulaziz University

An additive functor F:A→B between additive categories is said to be objective,provided any morphism f in A with F(f)=0 factors through an object K with F(K)=*** concentrate on triangle functors between triangulated *** first aim of this paper is to characterize objective triangle functors F in several ***,we are interested in the corresponding Verdier quotient functors VF:A→A/Ker F,in particular we want to know under what conditions VF is *** third question to be considered concerns the possibility to factorize a given triangle functor F=F2F1with F1a full and dense triangle functor and F2a faithful triangle *** turns out that the behavior of splitting monomorphisms and splitting epimorphisms plays a decisive role.

关键词： triangulated category triangle functor objective functor Verdier functor