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Differences between lower extremity joint running kinetics captured by marker-based and markerless systems were speed dependent

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Journal of Sport and Health Science 2024年第4期13卷 569-578页

作者： Hui Tang Barry Munkasy li li Department of Health Sciences and Kinesiology Georgia Southern UniversityStatesboroGA 30458USA Department of Kinesiology and Health Education University of Texas at AustinAustinTX 78712USA

Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical *** research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as *** studies using markerless systems in clinical and sports settings are still ***,the present study compared running biomechanics estimated by marker-based and markerless *** running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating ***:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic *** series analysis and statistical parametric mapping were used to determine system ***:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most ***:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused *** on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless ***-based *** differences were amplified by running speed.

关键词： Biomechanics Motion capture Gait Statistical parametric mapping

Efficient and selective recovery of Gd(Ⅲ)via polyethyleneimine modification of lanthanum-based metal-organic frameworks

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Journal of Rare Earths 2024年第1期42卷 210-219,I0007页

作者： Wenhao li lijinhong Huang Bin Xiao Xiaoguang Duan Haike li Lang li Wanfu Huang Ganzhou Key Laboratory of Basin Pollution Simulation and Control Jiangxi University of Science and TechnologyGanzhou341000China Innovation Center for Water Quality Security Technology at Ganjiang River Basin Jiangxi University of Science and TechnologyGanzhou341000China Faculty of Science and Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin UniversityWAAustralia School of Architecture and Design Jiangxi University of Science and TechnologyGanzhou341000China School of Resources and Architectural Engineering Gannan University of Science and TechnologyGanzhou341000China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA5005Australia School of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China

With the development of the economy and the increasing demand for environmental protection,the efficient and selective recovery of Gd(Ⅲ)from actual wastewater is of critical *** this work,lanthanum-based metal-organic framework(LaBDC)materials were prepared by a hydrothermal method,and then polyethyleneimine(PEI)and LaBDC were combined by an impregnation method to form a novel LaBDC@xPEI *** prepared materials were characterized using Fourier transfo rm infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),B runauer-Emmett-Teller(BET),thermogravimetric analysis(TGA)and X-ray photoelectron spectroscopy(XPS).Experiments show that LaBDC@50%PEI has the highest adsorption capacity(181.77 mg/g)among lanthanum-based MOFs with different PEI loadings at pH=5.5,which is about 5.1 times that of bare *** adsorption isotherm analysis shows that LaBDC@50%PEI follows the Langmuir *** addition,the adsorption kinetics of LaBDC@50%PEI follows a pseudo-second-order kinetic model,indicating that the adsorption process is chemical *** is worth noting that LaBDC@50%PEI maintains good adsorption performance and stability after three recycling tests,and exhibits excellent selectivity in cation interference ***,the LaBDC@50%PEI composites possess good stability and hold great promises in rapid recovery of Gd(Ⅲ)from practical aqueous environments.

关键词： Wet-impregnation method Polyethylene imine Metaleorganic frameworks Lanthanum Recovery of Gd(Ⅲ) Rare earths

Transcriptomics and physiological analyses reveal that sulfur alleviates mercury toxicity in rice(Oryza sativa L.)

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Journal of Environmental Sciences 2024年第1期135卷 10-25页

作者： Yingmei Huang Jicai Yi Xiaomin li Fangbai li National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and ManagementInstitute of Eco-Environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China College of life Sciences South China Agricultural UniversityGuangzhou 510642China SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSouth China Normal UniversityGuangzhou 510006China

Mercury(Hg)is one of the most dangerous contaminants and has sparked global concern since it poses a health risk to humans when consumed through ***(S)is a crucial component for plant growth,and S may reduce Hg accumulation in rice ***,the detailed effects of S and the mechanisms underlying S-mediated responses in Hg-stressed rice plants remain ***,to investigate the effects of S addition on rice growth,Hg accumulation,physiological indexes,and gene expression profiles,rice seedlings were hydroponically treated with Hg(20μmol/L Hg Cl_(2))and Hg plus elemental sulfur(100 mg/L).S application significantly reduced Hg accumulation in Hg-stressed rice roots and alleviated the inhibitory effects of Hg on rice growth.S addition significantly reduced Hg-induced reactive oxygen species generation,membrane lipid peroxidation levels,and activities of antioxidant enzymes while increasing glutathione content in *** analysis of roots identified 3,411,2,730,and 581 differentially expressed genes in the control(CK)***,CK ***+S,and Hg ***+S datasets,*** pathway of S-mediated biological metabolism fell into six groups:biosynthesis and metabolism,expression regulation,transport,stimulus response,oxidation reduction,and cell wall *** majority of biological process-related genes were upregulated under Hg stress compared with CK treatment,but downregulated in the Hg+S *** results provide transcriptomic and physiological evidence that S may be critical for plant Hg stress resistance and will help to develop strategies for reduction or phytoremediation of Hg contamination.

关键词： Sulfur Mercury Transcriptomics Detoxification

Cerium oxide inclusion nucleation mechanism based on classical nucleation theory and two-step nucleation

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Journal of Rare Earths 2024年第4期42卷 793-802页

作者： Yutang li Jun Wang linzhu Wang Chaoyi Chen Shufeng Yang Junqi li Xiang li School of Materials and Metallurgy Guizhou UniversityGuiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Department of Materials&Metallurgy Engineering Guizhou Institute of TechnologyGuiyang550003China

It is challenging to assess the mechanism responsible for the nucleation of inclusions in metals at high *** present work therefore systematically investigates the nucleation of cerium oxide inclusions according to classical nucleation theory and a two-step nucleation *** nucleation rates and nucleation radii of these inclusions are obtained,and the results demonstrate a considerable difference between theoretical and experimental *** the basis of a two-step nucleation mechanism,(CeO_(2))_(n) and(Ce_(2)O_(3))_(n)(n=1-6)clusters were constructed and the thermodynamic properties of both these clusters and of cerium oxide nanoparticles were *** addition,the entropies and heat capacity changes of cerium oxides were determined using first principles calculations and are found to be consistent with literature *** present data indicate that the cerium oxide inclusion nucleation pathway can be summarized as[Ce]+[O]→(CeO_(2))n/(Ce_(2)O_(3))_(n)→(Ce_(2)O_(3))_(n)→(Ce_(2)O_(3))_(2)→core(Ce_(2)O_(3)crystal)-shell((Ce_(2)O_(3))_(2) cluster)nanoparticles→(Ce_(2)O_(3))bulk.

关键词： Cerium oxide inclusion Classical nucleation theory Two-step nucleation mechanism First principles Rare earths

Boosting Hydrogen Storage Performance of MgH_(2) by Oxygen Vacancy-Rich H-V_(2)O_(5) Nanosheet as an Excited H-Pump

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Nano-Micro Letters 2024年第8期16卷 398-416页

作者： li Ren Yinghui li Zi li Xi lin Chong Lu Wenjiang Ding Jianxin Zou National Engineering Research Center of light Alloys Net Forming&State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Engineering Research Center of Mg Materials and Applications&School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Center of Hydrogen Science Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Instrumental Analysis Center of SJTU Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

MgH_(2) is a promising high-capacity solid-state hydrogen storage material,while its application is greatly hindered by the high desorption temperature and sluggish ***,intertwined 2D oxygen vacancy-rich V_(2)O_(5) nanosheets(H-V_(2)O_(5))are specifically designed and used as catalysts to improve the hydrogen storage properties of MgH_(2).The as-prepared MgH_(2)-H-V_(2)O_(5) composites exhibit low desorption temperatures(Tonset=185℃)with a hydrogen capacity of 6.54 wt%,fast kinetics(Ea=84.55±1.37 kJ mol^(-1) H_(2) for desorption),and long cycling ***,hydrogen absorption can be achieved at a temperature as low as 30℃ with a capacity of 2.38 wt%within 60 ***,the composites maintain a capacity retention rate of~99%after 100 cycles at 275℃.Experimental studies and theoretical calculations demonstrate that the in-situ formed VH_(2)/V catalysts,unique 2D structure of H-V_(2)O_(5) nanosheets,and abundant oxygen vacancies positively contribute to the improved hydrogen sorption ***,the existence of oxygen vacancies plays a double role,which could not only directly accelerate the hydrogen ab/de-sorption rate of MgH_(2),but also indirectly affect the activity of the catalytic phase VH_(2)/V,thereby further boosting the hydrogen storage performance of MgH_(2).This work highlights an oxygen vacancy excited“hydrogen pump”effect of VH_(2)/V on the hydrogen sorption of Mg/MgH_(2).The strategy developed here may pave a new way toward the development of oxygen vacancy-rich transition metal oxides catalyzed hydride systems.

关键词： Hydrogen storage MgH_(2) V_(2)O_(5)nanosheets Oxygen vacancies VH_(2)

铑(Ⅲ)离子印迹聚合物的制备及其作为吸附材料的应用探索

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贵金属 2014年第1期35卷 12-18页

作者：陶晋飞杨赟金李承蹊熊杰刘鹏曹秋娥云南大学化学科学与工程学院昆明650091 昆明冶金研究院昆明650091

以RhCl63-为模板,丙稀酰胺(AM)为功能单体,甲基丙烯酸乙二醇酯(EGDMA)为交联剂,采用分子印迹技术合成了一系列铑离子印迹聚合物(ⅡPs);研究了聚合条件和聚合方法对ⅡPs吸附性能的影响。结果发现,在模板、功能单体和交联剂的加入摩尔比为... 详细信息

以RhCl63-为模板,丙稀酰胺(AM)为功能单体,甲基丙烯酸乙二醇酯(EGDMA)为交联剂,采用分子印迹技术合成了一系列铑离子印迹聚合物(ⅡPs);研究了聚合条件和聚合方法对ⅡPs吸附性能的影响。结果发现,在模板、功能单体和交联剂的加入摩尔比为1:2:40时,用沉淀聚合法制备的铑离子印迹聚合物(ⅡP2)具有较高的吸附容量和最好的印迹效果。该印迹聚合物不仅可重复多次使用,而且在Rh(Ⅲ)与Pd(Ⅱ)、Pt(Ⅳ)、Ru(Ⅲ)、Ir(Ⅳ)、Cu(Ⅱ)、Ni(Ⅱ)及Fe(Ⅲ)之间的吸附选择性系数均在10以上,将其作为吸附材料用于分离富集添加了Rh(Ⅲ)的河水样品中的Rh(Ⅲ),回收率在90%左右,相对标准偏差在5.0%以下。

关键词：冶金物理化学铑离子印迹聚合物分子印迹技术吸附分离

A Two-stage Service-oriented Task Offloading Framework with Edge-cloud Collaboration:A Game Theory Approach

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Journal of Systems Science and Systems Engineering 2024年第5期33卷 521-551页

作者： Shiyong li Wenzhe li Huan liu Wei Sun School of Economics and Management Yanshan UniversityQinhuangdao 066004

With the fast development of Mobile Internet,data traffic generated by end devices is anticipated to witness substantial growth in the future ***,processing tasks locally will cause latency due to the limited resources of the end ***-cloud collaboration,an effective solution for latency-sensitive applications,is attracting greater attention from both industry and *** combines the advantages of the cloud center with abundant computing resources and edge nodes with low-latency *** this paper,we propose a two-stage task offloading framework with edge-cloud collaboration to assist end devices processing latency-sensitive tasks either on the edge servers or in the cloud *** for homogeneous task offloading,in the first stage,the competitive end devices offload tasks to the edge *** formulate the selfish task offloading problem among end devices as a potential *** the second stage,the edge nodes request resources from the cloud center to process end devices tasks due to their limited ***,we consider the heterogeneous task offloading problem and use intelligent optimization algorithm to obtain the optimal offloading *** results show that the service prices of edge nodes influence the decisions and task offloading costs of end *** also verify the intelligent optimization algorithm can achieve optimal performance with low complexity and fast convergence.

关键词： Edge-cloud collaboration task offloading potential game simulation annealing algorithm

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城市绿地植物景观密度的测量因子及评价指标

华中建筑 2019年第11期37卷 26-30页

作者：李承玺赵亚琳尹豪北京林业大学园林学院北京林业大学城乡生态环境北京实验室浙江农林大学风景园林与建筑学院

伴随着城市化的推进,城市面积在不断扩大,人们对于城市绿地空间和人居环境的需求也逐渐增加。园林植物是构成城市绿地的基本要素之一,对于城市绿地植物景观的研究也是城市绿地系统和城市规划研究与实践的重要组成部分。该文提出了城市... 详细信息

伴随着城市化的推进,城市面积在不断扩大,人们对于城市绿地空间和人居环境的需求也逐渐增加。园林植物是构成城市绿地的基本要素之一,对于城市绿地植物景观的研究也是城市绿地系统和城市规划研究与实践的重要组成部分。该文提出了城市绿地植物景观密度的相关概念,分析了城市绿地植物景观密度的变化因素,以促进今后城市绿地植物景观的配置合理化、密度适宜化以及物种丰富化,为今后风景园林行业对于城市绿地植物种植密度情况的研究提出建议。

关键词：城市绿地绿地植物景观密度植物群落

Effects of ignition voltage and electrode structure on electric ignition and combustion characteristics of Ammonium Dinitramide(ADN)-based liquid propellants in electric ignition mode in inert gas environment

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Chinese Journal of Aeronautics 2024年第4期37卷 229-242页

作者： Lei li Guoxiu li Hongmeng li Zhaopu YAO Tao ZHANG Jinze WU Shuo ZHANG School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Beijing Institute of Control Engineering Beijing 100190China

Hydrazine is toxic and carcinogenic, which greatly increases the difficulty of application and no longer meets the needs of green aerospace. As a green propellant, the Ammonium Dinitramide(ADN)-based liquid propellant has the advantages of higher specific impulse, being non-toxic,pollution-free, and easy storage. However, an ADN-based space engine in orbit has exposed the problems of high-temperature deactivation of catalysts and cold-start failure. An active ignition technology—electric ignition technology was explored in this paper to break through the technical bottleneck of catalyst deactivation and the inability to a cold start. An experimental system of a constant-volume combustor for the ADN-based liquid propellant based on the electric ignition method was established. The electric ignition and combustion characteristics of the ADN-based liquid propellant in a volume combustor with an electric ignition method were studied. The influencing mechanisms of the ignition voltage and the electrode structure on the electric ignition characteristics of the ADN-based liquid propellant were investigated. An elevation of the ignition voltage could facilitate the ignition process of the ADN-based liquid propellant, curtail electric energy input and heating effect, while exerting an adverse impact on the combustion process of the *** increase in the ignition voltage enhanced the ignition process of the propellant while simultaneously suppressing its combustion process when utilizing mesh electrodes. Compared to the strip electrodes, the mesh electrodes increased the contact area between the electrodes and the propellant,increased the electric energy input power in the electric ignition process, and reduced the ignition delay time. The mesh electrodes could promote the combustion process of the propellant to a certain extent.

关键词： ADN-based liquid propellant Resistive ignition Electrical ignition characteristic Combustion Inert gas