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Journal of Magnesium and Alloys 2023年第6期11卷 2142-2150页

作者： Rui Peng Yongcheng Lu Liang Shi Guoliang Yu Yuanming Lai Gang wang Yuanxun Li Hua su Huaiwu Zhang State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China China Jiliang University Hangzhou 310018China Chengdu University of Technology Chengdu 610059China

With the help of the first principle calculation,the solid-state reaction experiment was conducted to investigate the alteration in the sintering and the microwave dielectric properties of Mg_(3)B_(2)O_(6)ceramic with many Zn^(2+)*** properties were characterized using the scanning electron microscopy,network analyzer,X-ray diffraction,Raman spectroscopy,energy-dispersive spectroscopy,and thermomechanical and differential-thermal *** coexistence of Mg_(3)B_(2)O_(6),Mg_(2)B_(2)O_(5)and ZnO ceramics could be observed with increasing Zn^(2+)addition,and the lattice distortion occurred in the Mg_(2)B_(2)O_(5)and Mg_(3)B_(2)O_(6)ceramics due to the substitution of Mg^(2+)with Zn^(2+).The electron density and the bond property of the MgO_(6)octahedron changed,and a quantitative method was used to discuss the variation in sintering,substitution and phase formation *** densification window was decreased to 1100℃,and the dielectric properties improved with the formation of a three-phase borate solid solution(dielectric constant=6.73,quality factor=112,000 GHz at 16 GHz(Q=7000),temperature coefficient of resonant frequency=-61.2 ppm℃^(-1),and relative density=97.0%).

关键词： DFT Borate Solid solutions Dielectric properties

Proof of Security of a Semi-Device-Independent Quantum Key Distribution Protocol

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Chinese Physics Letters 2017年第2期34卷 7-10页

作者： Peng Xu Wan-su Bao Hong-Wei Li Yang wang Hai-Ze Bao The PLA Information Engineering University Zhengzhou 450001

Semi-device-independent quantum key distribution （SDI-QKD） has been proposed by applying the quantum dimension correlation, and the security relies on the violation of quantum dimension witness inequalities. We prove the security of the SDI-QKD protocol under the depolarization channel by considering the quantum dimension witness inequalities and minimum entropy and the specific process of the QKD protocol, combining with a four- quantum-state preparation and three measurement bases. We also provide the relationship between the dimension witness value, the error rate and the security key rate by the numerical simulation.

关键词： QKD Proof of Security of a Semi-Device-Independent Quantum Key Distribution Protocol SDI

In-materio reservoir computing based on nanowire networks:fundamental,progress,and perspective

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Materials Futures

Materials Futures 2023年第2期2卷 79-93页

作者： Renrui fang Woyu Zhang Kuan Ren Peiwen Zhang Xiaoxin Xu Zhongrui wang Dashan Shang State Key Laboratory of Fabrication Technologies for Integrated Circuits Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029People’s Republic of China Department of Electrical and Electronic Engineering The University of Hong KongHong Kong 999077People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

The reservoir computing(RC)system,known for its ability to seamlessly integrate memory and computing functions,is considered as a promising solution to meet the high demands for time and energy-efficient computing in the current big data landscape,compared with traditional silicon-based computing systems that have a noticeable disadvantage of separate storage and *** review focuses on in-materio RC based on nanowire networks(NWs)from the perspective of materials,extending to reservoir devices and *** common methods used in preparing nanowires-based reservoirs,including the synthesis of nanowires and the construction of networks,are firstly systematically *** physical principles of memristive and memcapacitive junctions are then ***,the dynamic characteristics of nanowires-based reservoirs and their computing capability,as well as the neuromorphic applications of NWs-based RC systems in recognition,classification,and forecasting tasks,are explicated in ***,the current challenges and future opportunities facing NWs-based RC are highlighted,aiming to provide guidance for further research.

关键词： reservoir computing nanowire networks short-term memory dynamic characteristics neuromorphic computing

Air-core characteristics in a swirling tunnel flow

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Journal of Hydrodynamics 2022年第4期34卷 634-646页

作者： Jun-hu Nan Huan Gao Chao-qun wang Kang-ning Ma James Yang Jia-fang Wei Guo-dong Li State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi'an University of TechnologyXi'an 710048China College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Civil and Architectural Engineering Royal Institute of Technology(KTH)StockholmSweden

A cost-effective technique to dissipate the energy in hydropower systems is the formation of a swirling flow within a *** such flows,an air core with a significant cross section usually *** reveal the air-core features in the horizontal tunnel of a high-head shaft spillway,laboratory tests,numerical modeling,and prototype observations are performed,to examine issues such as the formation of the air core,the interjacent air motion,the air-carrying capacity,and the scale *** is shown that the shape of the air core varies greatly in the axial and radial directions along the tunnel and that the center of the core deviates from the axis of the *** motion of the air within the core is caused by the combined action of the water entrainment on the inner surface of the swirling flow and the axial pressure difference in the air *** aeration process can be divided into five processes with respect to the changes of the gate openings.A theoretical expression is established for the air-carrying capacity of the swirling *** vacuum degree is the similarity condition of the air-carrying capacity of the swirling flow between the model and prototype tests based on the Froude law of the similitude,and this similarity condition is verified by both the model and prototype *** work provides a reference for the application of the swirling flows in horizontal hydropower tunnels.

关键词： Horizontal tunnel swirlingflow air core air-carrying capacity scale effect

Numerical study on the fracturing mechanism of shock wave interactions between two adjacent blast holes in deep rock blasting

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 735-746页

作者： Yuan Wei Liu Shangge wang Wei su Xuebin Li Zonghong Li Jiaxin Wen Lei Chang Jiangfang sun Xiaoyun School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang 050043 China Hebei Technology and Innovation Center on Safe and Effi cient Mining of Metal Mines Shijiazhuang 050043 China CCCC Second Highway Consultants Co. Ltd. Wuhan 430056 China China National Uranium Co. Ltd. Beijing 100013 China

With the application of electronic detonators, millisecond blasting is regarded as a signifi cant promising approach to improve the rock fragmentation in deep rock blasting. Thus, it is necessary to investigate the fracturing mechanisms of short-delay blasting. In this work, a rectangle model with two circle boreholes is modeled as a particles assembly based on the discrete element method to simulate the shock wave interactions induced by millisecond blasting. The rectangle model has a size of 12 × 6 m (L × W) and two blast holes have the same diameter of 12 cm. The shock waves are simplifi ed as time-varying forces applied at the particles of walls of the two boreholes. Among a series of numerical tests in this study, the spacing between two adjacent boreholes and delay time of millisecond blasting are considered as two primary variables, and the decoupling charge with a coeffi cient of 1.5 is taken into account in each case. The results show that stress superposition is not a key factor for improving rock fragmentation (tensile stress interactions rather than compressive stress superposition could aff ect the generation of cracks), whereas collision actions from isolated particles or particles with weakened constraints play a crucial role in creating the fracture network. The delay time has an infl uence on causing cracks in rock blasting, however, whether it works heavily depends on the distance between the two holes.

关键词： rock fragmentation millisecond blasting shock wave decoupling charge discrete element method

Fe48Co52 Alloy Nanowire Arrays： Effects of Magnetic Field Annealing

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Chinese Journal of Chemical Physics 2009年第1期22卷 82-86页

作者： Hai-lin su Shao-long Tang Rui-long wang Yi-qing Chen Chong Jia You-wei Du School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China National Laboratory of Solid State Microstructure and Department of Physics Nanjing University Nanjing 210093 China

The effects of magnetic field annealing on the properties of Fe48Co52 alloy nanowire arrays with various interwire distances （Di=30-60 nm） and wire diameters （Dw=22-46 nm） were investigated in detail. It was found that the array＇s best annealing temperature and crys- talline structure did not show any apparent dependence on the treatment of applying a 3 kOe magnetic field along the wire during the annealing process. For arrays with small Dw or with large Di, the treatment of magnetic field annealing also had no obvious influence on their magnetic performances. However, such a magnetic field annealing constrained the shift of the easy magnetization direction and improved the coercivity and the squareness obviously for arrays with large Dw or with small Di. The difference in the intensity of the effective anisotropic field within the arrays was believed to be responsible for this different variation of the array＇s magnetic properties after magnetic field annealing.

关键词： FeCo alloy, Nanowire array, Magnetic field annealing, Magnetic property Effective anisotropie field

Decreased Plasma MANF Levels are Associated with Type 2 Diabetes

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Biomedical and Environmental Sciences 2021年第3期34卷 236-240页

作者： wang Cong PENG Jia Jia MAO He LIU Dong fang and ZHANG Li Li Department of Endocrinology the Second Affiliated HospitalChongqing Medical UniversityChongqing 400010China

Type 2 diabetes mellitus(T2DM)is a multifactorial disease caused by both genetic and environmental *** many genes have been reported to be involved in T2DM,much is still unknown about other genes that are involved in the disease and its ***,the exploration of new factors plays a pivotal role in the development of new methods and strategies to prevent this chronic disease.

关键词： T2DM Diabetes Type

Prediction model for atmospheric corrosion of 7005-T4 aluminum alloy in industrial and marine environments

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1313-1319页

作者： Xiao-guang sun Peng Lin Cheng Man Jian Cui Hai-bo wang Chao-fang Dong Xiao-gang Li CRRC Qingdao Sifang Co. Ltd. Corrosion and Protection Center University of Science and Technology Beijing

Accelerated corrosion tests of the 7005-T4 aluminum alloy were conducted to determine a suitable service life prediction method by using alternating wet–dry cycles in three kinds of solutions. The morphology and composition analysis of the corrosion product revealed that slight corrosion occurred on the surfaces of the samples immersed in a 0.25 wt% Na_2S_2O_8 solution. However, pitting corrosion occurred on the surfaces of the samples immersed in a 3.5 wt% NaCl solution, whereas exfoliation corrosion occurred on the surfaces of the samples immersed in a mixture of 0.25 wt% Na_2S_2O_8 and 3.5 wt% NaCl solutions. A power exponent relationship was observed between the mass loss and exposure time of the 7005-T4 aluminum alloy immersed in the three kinds of solutions. In the mixture of 0.25 wt% Na_2S_2O_8 and 3.5 wt% NaCl solutions, the mass loss of the aluminum alloy yielded the maximum value. Based on the calculation of the correlation coefficients, the alternating wet–dry procedure in a 3.5 wt% NaCl solution could be used to predict the corrosion behavior of 7005-T4 aluminum alloy exposed in the atmosphere of Qingdao, China. The prediction model is as follows: T = 104.28×t^(0.91), where T is the equivalent time and t is the exposure time.

关键词： aluminum alloy atmospheric corrosion accelerated test correlation coefficient relational model

THREE ASPECTS ON SOLVING QUEUING SERVICE SYSTEM IN SHANGHAI WORLD EXPO

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Journal of Systems Science and Systems Engineering 2013年第3期22卷 340-361页

作者： Jifa GU Shanying XU Yong fang Kan SHI Benfu LV Geng PENG Bo wang Li SONG Rong XIE Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Management University of Chinese Academy of Sciences School of Management Shanghai University of Science and Technology Institute of Image Communication and Information Processing Shanghai Jiaotong University

This paper analyzes the queuing problem that was experienced during the Shanghai World Expo of 2010. The queuing problem will be discussed at three levels. The three levels include the physical, psychological, and social aspects of the queuing problem. The collective behavior of visitors is studied through analyzing the information from the different sources, such as, the network of electronic eyes, the evaluation platform based on mobile phone system and the Internet. A hybrid information network technology is implemented. Based on the Wuli-Shili-Renli （WSR） system methodology, a new theoretical analysis framework for the queuing problem is proposed.

关键词： Shanghai world expo queuing system psychology satisfactory

On the role of Zn and Fe doping in nitrogen-carbon electrocatalysts for oxygen reduction

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Nano Research 2024年第11期17卷 9564-9572页

作者： Yanan Zou Yuanyuan su Yongchao Yu Jinliang Luo Xiaomin Kang Jun Zhang Linghan Lan Tianshi wang Jun Li College of Mechanical Engineering University of South China Hengyang 421001 China Key Laboratory of Low-grade Energy Utilization Technologies and Systems Chongqing University Ministry of Education of China Chongqing 400044 China College of New Energy Zhengzhou University of Light Industry Zhengzhou 450002 China School of Mechanical and Electrical Engineering Guilin University of Electronic Technology Guilin 541004 China

Zn is a frequently used and sometimes even an inevitably involved element (when zeolitic imidazolate framework-8 (ZIF-8) is adopted as the precursor) for preparing high-performance Fe-N-C oxygen reduction reaction (ORR) catalysts. However, how the Zn element affects the physicochemical architecture of the catalysts, how it enhances the catalytic activity and whether Zn atoms serve as the active centers remain unclear. Herein, we proposed a novel route that adopted pyrrole as the precursor and flexibly controlled the addition of exogenous Zn and Fe dopants before pyrrole polymerization. In this way, a series of nitrogen-carbon catalysts with or without Zn or Fe doping were synthesized. The detailed characterization revealed the role of Zn and Fe doping in the catalyst morphology, pore structure, active site configurations, ORR catalytic activity and fuel cell performance. Importantly, the findings revealed that Zn doping has little effect on the ORR mechanism and pathway. It enhances ORR activity primarily by increasing the number of active sites via introducing more micro- and meso-pores, rather than by creating new active sites. While Fe doping participated in forming both pores and active site centers. Moreover, the catalyst that co-doped with Zn and Fe atoms (Zn-FeNC), synthesized via this simple and template-free route we proposed, presented a unique hollow and hierarchical pore structure with highly boosted ORR activity. It exhibited a 40 mV higher E 1/2 value than Pt/C in alkaline media, along with a rapid current response in air-cathode of the direct formate fuel cell. These results are valuable in guiding the synthesis of high-performance Fe-N-C catalysts.

关键词： oxygen reduction reaction Fe-N-C catalysts hollow porous nanocarbon Zn doping direct formate fuel cell