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Energy & Environmental Materials 2024年第2期7卷 18-29页

作者： Li yuan Wenlong Cai Yunhong Wei Yiran Pu Can Liu Yun Zhang hao Wu College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026China

Efficient energy storage devices with suitable electrode materials,that integrate high power and high energy,are the crucial requisites of the renewable power source,which have unwrapped new possibilities in the sustainable development of energy and the ***,a facile collagen microstructure modulation strategy is proposed to construct a nitrogen/oxygen dual-doped hierarchically porous carbon fiber with ultrahigh specific surface area(2788 m^(2)g^(-1))and large pore volume(4.56 cm^(3)g^(-1))via local microfibrous breakage/disassembly of natural structured *** operando spectroscopy and density functional theory unveil that the dual-heteroatom doping could effectively regulate the electronic structure of carbon atom framework with enhanced electric conductivity and electronegativity as well as decreased diffusion resistance in favor of rapid pseudocapacitive-dominated Li^(+)-storage(353 mAh g^(-1)at 10 A g^(-1)).Theoretical calculations reveal that the tailored micro-/mesoporous structures favor the rapid charge transfer and ion storage,synergistically realizing high capacity and superior rate performance for NPCF-H cathode(75.0 mAh g^(-1)at 30 A g^(-1)).The assembled device with NPCF-H as both anode and cathode achieves extremely high energy density(200 Wh kg^(-1))with maximum power density(42600 W kg^(-1))and ultralong lifespan(80%capacity retention over 10000 cycles).

关键词： collagen carbon energy storage device theoretical calculations topological structure modulation ultrahigh power and energy density

Absence of metallicity and bias-dependent resistivity in low-carrier-density EuCd_(2)As_(2)

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 119-125页

作者： Yuxiang Wang Jianwen Ma Jian yuan Wenbin Wu Yong Zhang Yicheng Mou Jiaming Gu Peihong cheng Wu Shi Xiang yuan Jinglei Zhang Yanfeng Guo cheng Zhang State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field Laboratory of the Chinese Academy of SciencesHefei 230031China School of Physics and Electronic Science East China Normal UniversityShanghai 200241China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China ShanghaiTech Laboratory for Topological Physics Shanghai 201210China

EuCd_(2)As_(2)was theoretically predicted to be a minimal model of Weyl semimetals with a single pair of Weyl points in the ferromagnet ***,the heavily p-doped Eu Cd_(2)As_(2)crystals in previous experiments prevent direct identification of the semimetal ***,we present a comprehensive magneto-transport study of high-quality Eu Cd_(2)As_(2)crystals with ultralow bulk carrier density(10^(13)cm^(-3)).In contrast to the general expectation of a Weyl semimetal phase,Eu Cd_(2)As_(2)shows insulating behavior in both antiferromagnetic and ferromagnetic states as well as surface-dominated conduction from band ***,the application of a dc bias current can dramatically modulate the resistance by over one order of magnitude,and induce a periodic resistance oscillation due to the geometric *** nonlinear transport results from the high nonequilibrium state induced by an electrical field near the band *** results suggest an insulating phase in Eu Cd_(2)As_(2)and put a strong constraint on the underlying mechanism of anomalous transport properties in this system.

关键词： magnetic Weyl semimetal quantum transport Hall effect nonlinear resistivity

Predominant types of regional cold waves in North China and their historical changes

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Atmospheric and Oceanic Science Letters 2024年第4期17卷 46-51页

作者： Xinyi cheng Yiyi Zhang Jiandong Li Xin hao Center for Climate System Prediction Research/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University of Information Science&TechnologyNanjingChina Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjingChina

寒潮事件对东亚地区的社会经济,生态系统和人体健康影响巨大.根据1980-2019年间10月至次年3月的每日寒潮记录和K-means聚类,本文识别出了中国两种不同类型的区域性寒潮(T1和T2). T1区域性寒潮主要影响东北地区,T2区域性寒潮则主要影响... 详细信息

寒潮事件对东亚地区的社会经济,生态系统和人体健康影响巨大.根据1980-2019年间10月至次年3月的每日寒潮记录和K-means聚类,本文识别出了中国两种不同类型的区域性寒潮(T1和T2). T1区域性寒潮主要影响东北地区,T2区域性寒潮则主要影响华北和东部地区.与T1区域性寒潮相比, T2区域性寒潮强度更强,持续时间更长,影响范围更广. 1980–2019年期间, T1区域性寒潮的频率显著增加,而T2区域性寒潮的频率则没有趋势变化. T1和T2区域性寒潮事件均与西伯利亚高压增强有关,然而与它们相关的对流层中层波列明显不同.在T1区域性寒潮事件发生期间,西伯利亚-蒙古上空出现负-正模态的500-hPa位势高度异常波列,削弱了东亚大槽,导致西伯利亚冷空气东移.T1区域寒潮频次增加趋势可能与全球变暖引起的500-hPa位势高度的线性趋势变化有关.与T2区域寒潮事件相关的波列则在乌拉尔山脉,蒙古和华北地区形成了脊-槽-脊环流异常,导致冷空气向东南方向入侵.本文得出结论,由于两类区域寒潮影响不同,西伯利亚高压增强和对流层中层波列模态在我国区域性寒潮事件的预报中应综合考虑.

关键词：寒潮 K-means聚类西伯利亚高压波列

Segment differential aggregation representation and supervised compensation learning of ConvNets for human action recognition

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Science China(Technological Sciences) 2024年第1期67卷 197-208页

作者： REN ZiLiang ZHANG QieShi cheng Qin XU ZhenYu yuan Shuai LUO DeLin School of Computer Science and Technology Dongguan University of TechnologyDongguan 523808China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China School of Electronic Engineering and Automation Guilin University of Electronic TechnologyGuilin 541004China Department of the mechanical engineering Erlangen-Nuremberg UniversityErlangen 91508Germany School of Aerospace Engineering Xiamen UniversityXiamen 361102China

With more multi-modal data available for visual classification tasks,human action recognition has become an increasingly attractive ***,one of the main challenges is to effectively extract complementary features from different modalities for action *** this work,a novel multimodal supervised learning framework based on convolution neural networks(Conv Nets)is proposed to facilitate extracting the compensation features from different modalities for human action *** on information aggregation mechanism and deep Conv Nets,our recognition framework represents spatial-temporal information from the base modalities by a designed frame difference aggregation spatial-temporal module(FDA-STM),that the networks bridges information from skeleton data through a multimodal supervised compensation block(SCB)to supervise the extraction of compensation *** evaluate the proposed recognition framework on three human action datasets,including NTU RGB+D 60,NTU RGB+D 120,and *** results demonstrate that our model with FDA-STM and SCB achieves the state-of-the-art recognition performance on three benchmark datasets.

关键词： action recognition segment frame difference aggregation supervised compensation learning ConvNets

Self-initiated static-dynamic state transition behavior and triggering mechanism of strain rockburst using three-dimensional discrete element method

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Underground Space 2024年第3期16卷 143-163页

作者： yuan Qian cheng Zhao Rui Wei Rui Zhang Lin Huang Huiguan Chen Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China School of Engineering Tibet UniversityLhasaTibet850000China

The accurate understanding of rockburst mechanism poses a global challenge in the field of rock *** for strain rockburst,achieving self-initiated static-dynamic state transition is a crucial step in the formation of catastrophic ***,the state transition behavior and its impact on rockburst have not received sufficient attention,and are still poorly ***,this study specifically focuses on the state transition behavior,aiming to investigate its abrupt transition process and formation mechanism,and triggering effects on *** facilitate the study,a novel burst rock-surrounding rock combined laboratory test model is proposed and its effectiveness is validated through experiment ***,corresponding numerical models are established using the three-dimensional(3D)discrete element method(DEM),enabling successful simulation of static brittle failure and rockbursts of varying intensities under quasi-static displacement loading ***,through secondary development,comprehensive recording of the mechanical and energy information pertaining to the combined specimen system and its subsystems is *** a result of numerical investigation studies,the elastic rebound dynamic behavior of the surrounding rock was discovered and identified as the key factor triggering rockburst and controlling its *** impact loading on the burst rock,induced by elastic rebound,directly initiates the dynamic processes of rockburst,serving as the direct ***,the transient work and energy convergence towards the burst rock resulting from elastic rebound are recognized as the inherent cause of ***,it has been observed that a larger extent of surrounding rock leads to a stronger elastic rebound,thereby directly contributing to a more intense *** findings can provide novel theoretical insights for the exploring of rockburst mechanism and the development of monitoring and

关键词： Strain rockburst Static-dynamic state transition Self-initiation Triggering mechanism Elastic rebound Discrete element method

Early peripheral perfusion index predicts 28-day outcome in patients with septic shock

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World Journal of Emergency Medicine 2024年第5期15卷 372-378页

作者： cheng Chi hao Gong Kai Yang Peng Peng Xiaoxia Zhang Department of Emergency Peking University People's HospitalBeijing 100044China Department of Emergency Intensive Care Unit the First Affi liated Hospital of Xinjiang Medical UniversityUrumqi 830000China

BACKGROUND:To investigate the prognostic value of the peripheral perfusion index(PPI)in patients with septic ***:This prospective cohort study,conducted at the emergency intensive care unit of Peking University People's Hospital,recruited 200 patients with septic shock between January 2023 and August *** patients were divided into survival(n=84)and death(n=116)groups based on 28-day *** evaluations included laboratory tests and clinical scores,with lactate and PPI values assessed upon admission to the emergency room and at 6 h and 12 h after *** factors associated with mortality were analyzed using univariate and multivariate Cox regression *** operator characteristic(ROC)curve was used to assess predictive *** rates were compared,and Kaplan-Meier survival plots were ***:Compared to the survival group,patients in the death group were older and had more severe liver damage and coagulation dysfunction,necessitating higher norepinephrine doses and increased fl uid *** lactate levels and lower PPI levels at 0 h,6 h,and 12 h were observed in the death *** Cox regression identifi ed prolonged prothrombin time(PT),decreased 6-h PPI and 12-h PPI as independent risk factors for *** area under the curves for 6-h PPI and 12-h PPI were 0.802(95%CI 0.742-0.863,P<0.001)and 0.945(95%CI 0.915-0.974,P<0.001),respectively,which were superior to Glasgow Coma Scale(GCS),Sequential Organ Failure Assessment(SOFA)scores(0.864 and 0.928).Cumulative mortality in the low PPI groups at 6 h and 12 h was signifi cantly higher than in the high PPI groups(6-h PPI:77.52%vs.22.54%;12-h PPI:92.04%vs.13.79%,P<0.001).CONCLUSION:PPI may have value in predicting 28-day mortality in patients with septic shock.

关键词： Peripheral perfusion index Septic shock Prognosis Predictive value

Influences of shale microstructure on mechanical properties and bedding fractures distribution

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Petroleum Science 2024年第3期21卷 1944-1954页

作者： Ming-Zhe Gu Mao Sheng Shi-Zhong cheng Fan-hao Gong Gen-Sheng Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing2249China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Shenyang Center of China Geological Survey ShenyangLiaoning110034China

The difference in microstructure leads to the diversity of shale mechanical properties and bedding fractures distribution *** this paper,the microstructure and mechanical properties of Longmaxi marine shale and Qingshankou continental shale were studied by X-ray diffractometer(XRD),field emission scanning electron microscope(FE-SEM)with mineral analysis system,and ***,the typical bedding layers area was properly stratified using Focused Ion Beam(FIB),and the effects of microstructure and mechanical properties on the distribution patterns of bedding fractures were *** results show that the Longmaxi marine shale sample contains more clay mineral grains,while the Qingshankou continental shale sample contains more hard brittle mineral grains such as *** Longmaxi marine shale sample,hard brittle minerals with grain sizes larger than 20μm is18.24%and those with grain sizes smaller than 20μm is 16.22%.For Qingshankou continental shale sample,hard brittle minerals with grain sizes larger than 20μm is 40.7%and those with grain sizes smaller than 20μm is 11.82%.In comparison to the Qingshankou continental shale sample,the Longmaxi marine shale sample has a lower modulus,hardness,and *** shales are formed by alternating coarse-grained and fine-grained layers during *** average single-layer thickness of Longmaxi marine shale sample is greater than Qingshankou continental shale *** two types of shale have similar bedding fractures distribution patterns and fractures tend to occur in the transition zone from coarse-grained to fine-grained *** orientation of the fracture is usually parallel to the bedding plane and detour occurs in the presence of hard brittle *** fracture distribution density of the Longmaxi marine shale sample is lower than that of the Qingshankou continental shale sample due to the strong heterogeneity of the Qingshankou continental *** current resea

关键词： Shale Nanoindentation Microstructure Mechanical property Fracture

Method of improving pedestrian navigation performance based on chest card

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Journal of Systems Engineering and Electronics 2024年第4期35卷 987-998页

作者： cheng hao GAO Shuang CAI Xiaowen WANG Yuxuan WANG Jie School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China School of Automation and Electronic Information Xiangtan UniversityXiangtan 411105China Navigation Guidance and Control Graduate School of the Second Institute of China Aerospace Science and Industry CorporationBeijing 100854China

With the development of positioning technology,loca-tion services are constantly in demand by *** a primary location service pedestrian navigation has two main approaches based on radio and inertial *** pedestrian naviga-tion based on radio is subject to environmental occlusion lead-ing to the degradation of positioning *** pedestrian navigation based on micro-electro-mechanical system inertial measurement unit(MIMU)is less susceptible to environmental interference,but its errors dissipate over *** this paper,a chest card pedestrian navigation improvement method based on complementary correction is proposed in order to suppress the error divergence of inertial navigation *** suppress atti-tude errors,optimal feedback coefficients are established by pedestrian motion *** extend navigation time and improve positioning accuracy,the step length in subsequent movements is compensated by the first step *** experi-mental results show that the positioning accuracy of the pro-posed method is improved by more than 47%and 44%com-pared with the pure inertia-based method combined with step compensation and the traditional complementary filtering com-bined method with step *** proposed method can effectively suppress the error dispersion and improve the positioning accuracy.

关键词： pedestrian navigation micro-electro-mechanical sy-stem(MEMS) inertial navigation complementary filtering

Effect of Active–Passive Deformation on the Thrust by the Pectoral Fins of Bionic Manta Robot

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Journal of Bionic Engineering 2024年第2期21卷 718-728页

作者： Yang Lu Shaomin Meng cheng Xing Yiwei hao Yonghui Cao Guang Pan Yong Cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo315103China State Key Lab of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringZhejiang UniversityHangzhou310027China

Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient *** manta wings’deformation is evident during the swimming *** improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is *** this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)*** APD fin was actively controlled by two servo motors and could be passively deformed to variable *** APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of *** results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan *** average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral *** obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).

关键词： Manta ray Bionic pectoral fin Fin Ray®effect Active-passive deformation(APD)

Long-term efficacy and safety of Huangqi(Radix Astragali Mongolici)-based Traditional Chinese Medicine in diabetic peripheral neuropathy:a Meta-analysis of randomized controlled trials

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Journal of Traditional Chinese Medicine 2024年第2期44卷 229-242页

作者： PING Jing hao Hongzheng WU Zhenqi ZOU Meijuan LI Zuojing cheng Gang School of Life Sciences and Biopharmaceutics Shenyang Pharmaceutical UniversityShenyang 110000China Department of Endocrinology Affiliated Hospital of Liaoning University of Traditional Chinese MedicineShenyang 110000China Department of Research Administration Affiliated Hospital of Liaoning University of Traditional Chinese MedicineShenyang 110000China School of Pharmacy Shenyang Pharmaceutical UniversityShenyang 110000China

OBJECTIVE:To assess the long-term effectiveness of Huangqi(Radix Astragali Mongolici,HQ)-based Traditional Chinese Medicine(TCM)in the treatment of diabetic peripheral neuropathy(DPN).METHODS:Nine databases were searched to retrieve available randomized controlled trials that compared HQbased TCM and Western Medicines in the treatment of *** methodological quality of the included studies was assessed using the Cochrane bias risk tool,and RevMan 5.4 was used for data *** effect estimates of interest were risk ratio(RR),mean difference(MD)or standardized mean difference(SMD)with 95%confidence interval(CI).RESULTS:The results from 48 available studies assessing 3759 patients demonstrated that cases administered HQ-based TCM[RR=1.30,95%CI(1.21,1.40),P<0.00001]or HQ-based TCM combined with Western Medicines[RR=1.25,95%CI(1.19,1.31),P<0.00001]exhibited higher total efficacy rates than individuals who received Western Medicine *** results showed that the HQ-based TCM group had decreased Toronto Clinical Scoring System scores[MD=-1.50,95%CI(-1.83,-1.17),P<0.00001],and reduced serum interleukin 6[SMD=-0.57,95%CI(-0.87,-0.27),P=0.0002]and tumor necrosis factors-αlevels[SMD=-0.60,95%CI(-0.95,-0.25),P=0.0009].In addition,both HQ-based TCM and HQbased TCM combined with Western Medicine increased nerve conduction velocity and decreased glycaemia compared with Western Medicine *** terms of blood lipids,oxidative stress and adverse drug reactions,there were no significant differences between the HQ-based TCM groups and the Western Medicine control ***:The current Meta-analysis revealed that HQ-based TCM yields higher efficacy and safety than Western Medicine alone for the treatment of DPN,although further well-designed RCTs are required to validate these findings.

关键词： Huangqi(Radix Astragali Mongolici) medicine Chinese traditional diabetic peripheral neuropathy Meta-analysis