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CRYSTAL　STRUCTURES　OF　CHARGE　TRANSFER　SALTS　（TTMTTF）2Cu2Cl6　AND　C40H72N6Se4Ni

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中国科学院大学学报(中英文) 1995年第2期 149-156页

作者： Chen xue-an yang xue-yong Wu Pei-ji Zhu Dao-ben Fu Heng Tang You-qi (Institute of Chemistry, Academia Sinica, Beijing 100080)

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关键词： charge transfer salt crystal structures triclinic space group

Incidence of congenital heart disease in Beijing, China

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Chinese Medical Journal 2009年第10期122卷 1128-1132页

作者： yang xue-yong LI Xiao-feng LV Xiao-dong LIU Ying-long Pediatric Cardiac Center Department of Surgery Cardiovascular Institute and Fu Wai Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100037 China

Background The incidence of congenital heart disease has been studied in developed countries for many years, but rarely in the mainland of China. Fetal echocardiographic screening for congenital heart disease was first performed in Beijing in the early 2000s, but the impact was not clear. The current study was undertaken to determine the incidence of congenital heart disease in Beijing, China and to estimate the impact of fetal echocardiography on the incidence of liveborn congenital heart disease.Methods The study involved all infants with congenital heart disease among the 84 062 total births in Beijing during the period of January 1 and December 31, 2007. An echocardiographic examination was performed on every baby suspected to have congenital heart disease, prenatally or/and postnatally.Results A total of 686 infants were shown to have congenital heart disease among 84 062 total births. The overall incidence was 8.2/1000 total births. Mothers of 128 of 151 babies diagnosed prenatally were chosen to terminate the pregnancy. Two of the 151 infants died in utero. A specific lesion was identified for each infant and the frequencies of lesions were determined for each class of infants （total births, stillbirths and live births）. The incidence of congenital heart disease in stillbirths and live births was 168.8/1000 and 6.7/1000, respectively. The difference between the incidence of total birth and the incidence of live birth was statistically significant （P 〈0.001）. Conclusions The incidence of liveborn congenital heart disease in Beijing is within the range reported in developed countries. Fetal echocardiography reduce significantly the incidence of liveborn congenital heart disease.

关键词： incidence congenital heart disease prenatal diagnosis fetal echocardiography pregnancy termination

Quantum Tunneling Enhanced Hydrogen Desorption from Graphene Surface: Atomic versus Molecular Mechanism

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Chinese Physics Letters 2024年第8期41卷 58-68页

作者： yangwu Tong yong yang Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China Key Lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China

We study the desorption mechanism of hydrogen isotopes from graphene surface using first-principles calculations,with focus on the effects of quantum *** low temperatures,quantum tunneling plays a dominant role in the desorption process of both hydrogen monomers and *** the case of dimer desorption,two types of mechanisms,namely the traditional one-step desorption in the form of molecules(molecular mechanism),and the two-step desorption in the form of individual atoms(atomic mechanism),are studied and *** the ortho-dimers,the dominant desorption mechanism is found to switch from the molecular mechanism to the atomic mechanism above a critical temperature,which is∼300K and 200K for H and D,respectively.

关键词： desorption quantum mechanism

Environment-adaptive phase-separation-porous fluorofilm for highperformance passive radiation cooling

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Nano Research 2024年第6期17卷 5636-5644页

作者： Weiming Tang yong Li xue Meng Shutao Wang Ziguang Zhao School of Future Technology University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Passive radiative cooling is widely recognized as an environmentally sustainable method for achieving significant cooling ***,the mechanical properties and environmental adaptability of current radiative cooling materials are not sufficient to maintain high cooling performance in external *** we reported an environment-adaptive phase-separation-porous fluorofilm for high-performance passive radiation *** to the homogenous fluoro-porous network with limited scattering efficiencies,we modulated the porous structure of the fluorofilm to achieve a strong emissivity of 95.2%(8-13μm)and a high reflectivity of 97.1%(0.3-2.5μm).The fluorofilm demonstrates a temperature drop of 10.5°C and an average cooling power of 81 W·m^(−2)under a sunlight power of 770 W·m^(−2).The high mechanical performance and environmental adaptability of fluorofilms are also *** its significant radiative cooling capability and robust environmental adaptability,the fluorofilm is expected to have a promising future in radiative temperature regulation.

关键词： fluorofilm passive radiation cooling porous optimization thermal regulation

A Review on Engineering Transition Metal Compound Catalysts to Accelerate the Redox Kinetics of Sulfur Cathodes for Lithium–Sulfur Batteries

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Nano-Micro Letters 2024年第5期16卷 300-332页

作者： Liping Chen Guiqiang Cao yong Li Guannan Zu Ruixian Duan yang Bai Kaiyu xue yonghong Fu Yunhua Xu Juan Wang Xifei Li Shaanxi Key Laboratory of Nanomaterials and Nanotechnology Xi’an University of Architecture and TechnologyXi’an 710055People’s Republic of China Institute of Advanced Electrochemical Energy and School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048People’s Republic of China Yulin University Yulin 719000People’s Republic of China School of Materials Science and Engineering Fuzhou UniversityFuzhou 350108People’s Republic of China

Engineering transition metal compounds(TMCs)catalysts with excellent adsorption-catalytic ability has been one of the most effec-tive strategies to accelerate the redox kinetics of sulfur ***,this review focuses on engineering TMCs catalysts by cation doping/anion doping/dual doping,bimetallic/bi-anionic TMCs,and TMCs-based heterostructure *** is obvious that introducing cations/anions to TMCs or constructing heterostructure can boost adsorption-catalytic capacity by regulating the electronic structure including energy band,d/p-band center,electron filling,and valence ***,the elec-tronic structure of doped/dual-ionic TMCs are adjusted by inducing ions with different electronegativity,electron filling,and ion radius,resulting in electron redistribution,bonds reconstruction,induced vacancies due to the electronic interaction and changed crystal structure such as lat-tice spacing and lattice *** from the aforementioned two strategies,heterostructures are constructed by two types of TMCs with different Fermi energy levels,which causes built-in electric field and electrons transfer through the interface,and induces electron redistribution and arranged local atoms to regulate the electronic ***,the lacking studies of the three strategies to comprehensively regulate electronic structure for improving catalytic performance are pointed *** is believed that this review can guide the design of advanced TMCs catalysts for boosting redox of lithium sulfur batteries.

关键词： Lithium–sulfur battery Redox kinetic Transition metal compounds catalyst Multiple metals/anions

Double Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 75-90页

作者： Meng Chen Wang-xue Chen Rui yang Department of Mathematics and Statistics Jishou UniversityJishou416000China

The traditional simple random sampling(SRS)design method is inefficient in many *** proposed some new designs to increase *** this paper,as a variation of moving extremes ranked set sampling(MERSS),double MERSS(DMERSS)is proposed and its properties for estimating the population mean are *** turns out that,when the underlying distribution is symmetric,DMERSS gives unbiased estimators of the population ***,it is found that DMERSS is more efficient than the SRS and MERSS methods for usual symmetric distributions(normal and uniform).For asymmetric distributions considered in this study,the DMERSS has a small bias and it is more efficient than SRS for usual asymmetric distribution(exponential)for small sample sizes.

关键词： double moving extremes ranked set sampling symmetric distribution efficiency

ZnO/ZnS heterostructure in N-doped porous carbon for anchoring-diffusion-conversion of polysulfides for high-performance lithium-sulfur batteries

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Rare Metals 2024年第8期43卷 3661-3676页

作者： Fei Wang Rong-Wei Huang Wen-Chang Han Chun-Man yang Wen-Hao yang Peng Dong Chao-Ling Wu Yi-yong Zhang xue Li Ying-Jie Zhang National Local Joint Engineering Research Center for LithiumIon Batteries and Materials Preparation Technology Key Laboratory of Advanced Batteries Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China Engineering Research Center of Alternative Energy Materials and Devices Sichuan UniversityMinistry of EducationChengdu 610065China

The shuttle effect of polysulfides is one of the key factors hindering the commercialization of lithiumsulfur batteries(LSBs).Owing to their high conductivity and advantageous structure,heterostructures can be used in sulfur fixation and catalysis of *** this study,a flower-shaped ZnO/ZnS heterostructure on a nitrogendoped porous carbon(NPC) sulfur host was *** ZnO/ZnS heterostructure regulates the electronic structure of the material and exhibits higher metal-like ***,the ZnO/ZnS heterostructure combines the strong adsorption property of ZnO and the high catalytic ability of ZnS to realize the anchoring-diffusionconversion of lithium poly sulfides(LiPSs).Results reveal that the developed ZnO/ZnS@NPC/S cathode has excellent electrochemical performance in LSBs,achieving a high discharge specific capacity of 1365.3 mAh·g^(-1) at 0.1C and excellent rate capability(719 mAh·g^(-1) at 2C;the capacity decay rate is only 0.042% per cycle after 1000 cycles).Even under a high sulfur loading-E/S(electrolyte/sulfur)ratio of 5.1 mg·cm^(-2)-6 μl·mg^(-1),a high specific capacity of 723.7 mAh·g^(-1) is maintained after 60 *** study provides a new strategy for a multifunctional sulfur host that can effectively alleviate the shuttle effect of LiPSs and improve the utilization of sulfur active substances.

关键词： ZnO/ZnS heterostructure Lithium-sulfur batteries Density functional theory Anchor Conversion

UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： xue-yong Yu Wen-Jin Niu Ye Zhu Hong-Bo Zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

Dynamic SLAM Visual Odometry Based on Instance Segmentation:A Comprehensive Review

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Computers, Materials & Continua 2024年第1期78卷 167-196页

作者： Jiansheng Peng Qing yang Dunhua Chen Chengjun yang yong Xu yong Qin College of Automation Guangxi University of Science and TechnologyLiuzhou545000China Department of Artificial Intelligence and Manufacturing Hechi UniversityHechi547000China

Dynamic Simultaneous Localization and Mapping(SLAM)in visual scenes is currently a major research area in fields such as robot navigation and autonomous ***,in the face of complex real-world envi-ronments,current dynamic SLAM systems struggle to achieve precise localization and map *** the advancement of deep learning,there has been increasing interest in the development of deep learning-based dynamic SLAM visual odometry in recent years,and more researchers are turning to deep learning techniques to address the challenges of dynamic *** to dynamic SLAM systems based on deep learning methods such as object detection and semantic segmentation,dynamic SLAM systems based on instance segmentation can not only detect dynamic objects in the scene but also distinguish different instances of the same type of object,thereby reducing the impact of dynamic objects on the SLAM system’s *** article not only introduces traditional dynamic SLAM systems based on mathematical models but also provides a comprehensive analysis of existing instance segmentation algorithms and dynamic SLAM systems based on instance segmentation,comparing and summarizing their advantages and *** comparisons on datasets,it is found that instance segmentation-based methods have significant advantages in accuracy and robustness in dynamic ***,the real-time performance of instance segmentation algorithms hinders the widespread application of dynamic SLAM *** recent years,the rapid development of single-stage instance segmentationmethods has brought hope for the widespread application of dynamic SLAM systems based on instance ***,possible future research directions and improvementmeasures are discussed for reference by relevant professionals.

关键词： Dynamic SLAM instance segmentation visual odometry