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Science China(Technological Sciences) 2014年第9期57卷 1729-1737页

作者： luo wei WANG Bo ZHAO HaiSen luo YingLi Department of Mathematics Zhejiang University State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

The induction motor system with fluctuating potential loads is a non-linear complex electro-mechanical *** beam pumping motors as an example,this paper proposes a multiple factor non-linear mathematical model to study the operating performance of the induction motor *** model consists of non-linear time varying electromagnetic field equations,mechanical wave equations of sucker rods and non-linear coupling equation of reducer and four-bar *** equations are numerically solved by combining time-step finite element method(TS-FEM),finite difference method(FDM),a linear dimension reduction method and the Newton-Raphson *** results,which are validated by experiments,reveal the influence of the fluctuating potential load on magnetic field distributions,stator and rotor currents,the input power and the power *** model and simulation results provide theoretical and technical supports for subsequent researches on model simplification and energy saving technologies.

关键词： induction motors electromagnetic field equation wave equations TS-FEM finite difference method

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儿童常见呼吸道病毒感染的治疗进展

医学综述 2025年第1期31卷 59-64页

作者：魏贤超罗红芳贵州医科大学儿科学院贵阳550025 贵州医科大学第二附属医院儿科贵州凯里556000

呼吸道感染,尤其是呼吸道病毒感染作为儿童常见疾病之一,存在引起疾病流行或大流行的风险,严重危害儿童身体健康。儿童常见呼吸道病毒包括腺病毒、新型冠状病毒、呼吸道合胞病毒、流感病毒、猴痘病毒等,病毒感染后可触发多种机制,引起... 详细信息

呼吸道感染,尤其是呼吸道病毒感染作为儿童常见疾病之一,存在引起疾病流行或大流行的风险,严重危害儿童身体健康。儿童常见呼吸道病毒包括腺病毒、新型冠状病毒、呼吸道合胞病毒、流感病毒、猴痘病毒等,病毒感染后可触发多种机制,引起肺组织细胞的溶解和坏死,最终导致肺损伤和肺部后遗症。目前对于大多数病毒感染仍缺乏有效抗病毒药物,且疫苗研发困难,是临床治疗面临的重大挑战。未来对病毒的免疫治疗及疫苗的研发是呼吸道病毒治疗和预防的热点,如制备特异性单克隆抗体、开发具有多重效价的呼吸道病原体疫苗。

关键词：病毒性肺炎腺病毒新型冠状病毒呼吸道合胞病毒流感病毒猴痘病毒埃博拉病毒

Characteristics of rock fragments in different forest stony soil and its relationship with macropore characteristics in mountain area, northern China

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Journal of Mountain Science 2018年第3期15卷 519-531页

作者： MENG Chen NIU jian-zhi YIN Zheng-cong luo Zi-teng LIN Xing-na jia Jing-wei College of Soil and Water Conservation Beijing Forestry University Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees Beijing University of Agriculture Department of Geography Texas A&M University College Station

Rock fragments have major effect on soil macropores and water movement. However, the characteristics of rock fragments and their relationship with macropore characteristics remain elusive in forest stony soils in northern mountainous area of China. The objectives of this study are to(1) use Industrial Computed Tomography(CT) scanning to quantitatively analyze rock fragment characteristics in intact soil columns in different forest lands and(2) identify the relationship between characteristics of rock fragments and that of the macropores. Intact soil columns that were 100 mm in diameter and 300 mm long were randomly taken from six local forest stony soils in Wuzuolou Forest Station in Miyun, Beijing. Industrial CT was used to scan all soil column samples, and then the scanned images were utilized to obtain the three-dimensional(3 D) images of rock fragments and macropore structures. Next, theparameters of the rock fragments and macropore structure were measured, including the volume, diameter, surface area, and number of rock fragments, as well as the volume, diameter, surface area, length, angle, tortuosity and number of macropores. The results showed that no significant difference was found in soil rock fragments content in the 10-30 cm layer between mixed forest and pure forest, but in the 0-10 cm soil layer, the rock fragments in mixed forest were significantly less than in pure forest. The number density of macropores has significant negative correlation with the number of rock fragments in the 0-10 cm soil layer, whereas this correlation is not significant in 10-20 cm and 20-30 cm soil layers. The volume density of macropore was not correlated with the volume density of rock fragments, and there is no correlation between the density of macropore surface area and the density of rock fragment surface area. Industrial CT scanning combined with image processing technology canprovide a better way to explore 3 D distribution of rock fragments in soil. The content of

关键词： Rock fragment Macropore Forest stone soil Mountain area Industrial Computed Tomography

Changes in Water Use Efficiency Caused by Climate Change,CO_(2) Fertilization,and Land Use Changes on the Tibetan Plateau

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Advances in Atmospheric Sciences 2023年第1期40卷 144-154页

作者： Binghao jia Xin luo Longhuan WANG Xin LAI State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China Key Lab of Virtual Geographic Environment(Nanjing Normal University) Ministry of EducationNanjing 210023China jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Plateau Atmosphere and Environment Key Laboratory of Sichuan Province Chengdu University of Information TechnologyChengdu 610225China

Terrestrial ecosystem water use efficiency(WUE)is an important indicator for coupling plant photosynthesis and transpiration,and is also a key factor linking the carbon and water cycles between the land and ***,under the combination of climate change and human intervention,the change in WUE is still unclear,especially on the Tibetan Plateau(TP).Therefore,satellite remote sensing data and process-based terrestrial biosphere models(TBMs)are used in this study to investigate the spatiotemporal variations of WUE over the TP from 2001 to ***,the effects of land use and land cover change(LULCC)and CO_(2) fertilization on WUE from 1981-2010 are assessed using *** show that climate change is the leading contributor to the change in WUE on the TP,and temperature is the most important *** makes a negative contribution to WUE(-20.63%),which is greater than the positive contribution of CO_(2) fertilization(11.65%).In addition,CO_(2) fertilization can effectively improve ecosystem resilience on the *** the northwest plateau,the effects of LULCC and CO_(2) fertilization on WUE are more pronounced during the driest years than the annual *** findings can help researchers understand the response of WUE to climate change and human activity and the coupling of the carbon and water cycles over the TP.

关键词： water use efficiency gross primary productivity evapotranspiration Tibetan Plateau carbon and water cycle

Rapid chemical recycling of waste polyester plastics catalyzed by recyclable catalyst

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Green Chemical Engineering 2024年第2期5卷 257-265页

作者： Yu-Ji luo jia-Yin Sun Zhi Li School of Physical Science and Technology ShanghaiTech UniversityShanghai201210China

Waste plastics are serious environmental threats due to their low degradability and low recycling *** and efficient waste plastics recycling technologies are urgently demanded for a sustainable ***,we report a rapid,closed-loop,and streamlined process to convert polyesters such as poly(ethylene terephthalate)(PET)back to its purified *** trifluoromethanesulfonic acid or metal triflates as the recyclable catalyst,polyesters such as PET can be completely depolymerized by simple carboxylic acids within 1 *** coupling this acidolysis with a subsequent hydrogenolysis process,the consumed carboxylic acid was recovered and the closed-loop of PET depolymerization could be *** catalysts and depolymerization agents are fully recycled while only PET and hydrogen are consumed.

关键词： Chemical recycling Waste polyester plastics Acidolysis Recyclable catalyst

Structural Variation between the Western and Eastern Kuqa Fold-and-thrust Belt,China:Insights from Seismic Interpretation and Analog Modeling

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Acta Geologica Sinica(English Edition) 2023年第4期97卷 1078-1093页

作者： WANG wei XIE Huiwen YIN Hongwei jia Dong XU Zhenping luo Haoyu HE Wanhui YUAN Rui DUAN Yunjiang School of Earth Science and Engineering Nanjing UniversityNanjing 210046China Research Institute of Petroleum Exploration and Development Tarim Oilfield CompanyPetroChinaKorlaXinjiang 841000China

The Kuqa fold-and-thrust belt exhibits apparent structural variation in the western and eastern *** salt layer act as effective decollements and influence the varied *** this study,detailed seismic interpretations and analog modeling are presented to construct the suprasalt and subsalt structures in the transfer zone of the middle Kuqa and investigate the influence of the two salt *** results reveal that the relationship of the two salt layers changes from separated to connected,and then overlapped toward the foreland in the transfer *** structural models are formed in the suprasalt and subsalt units due to the interaction of the two salt *** imbricate thrust faults form two broom-like fault systems in the subsalt *** suprasalt units develop detached folds terminating toward the east in the region near the orogenic ***,two offset anticlines with different trends develop at the frontal edge of the lower salt layer and the trailing edge of the upper salt layer,*** to exploration results in this region,the relationship between suprasalt and subsalt structures has an influence on hydrocarbon *** believe that the connected deformation contains high-risk plays while the decoupled deformation contains well-preserved plays.

关键词： along-strike variation analog modeling 3D geometric model salt-related structure Kuqa fold-and-thrust belt

Design and cold test of S-BAND cavity BPM for HLS

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 292-295页

作者： luo Qing SUN BaoGen jia QiKa HE DuoHui FANG jia National Synchrotron Radiation Laboratory School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230029China

An S-band cavity BPM is designed for a new injector in National Synchrotron Radiation Laboratory. A re-entrant position cavity is tuned to the TM110 mode as position cavity. Cut-through waveguides are used as pickups to suppress the monopole signal. Theoretical resolution of this design is 31 nm. A prototype cavity BPM system is manufactured for off-line cold tests. The wire scanning method is used to calibrate the BPM and estimate the performance of the on-line BPM system. A cross-talk problem has been detected during the cold test. Racetrack cavity BPM design can be used to suppress the cross-talk. With the nonlinear effect being ignored, transform matrix can be used to correct cross-talk. Analysis of cold test results shows that the position resolution of prototype BPM is better than 3 μm.

关键词： cavity BPM re-entrant cut-through waveguide cold test wire scanning resolution cross-talk

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Quantum Spaces

Acta Mathematica Sinica,English Series 2010年第7期26卷 1323-1330页

作者： wei HE Mao Kang luo Department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China Institute of Mathematics Sichuan University Chengdu 610064 P. R. China

In this paper, a more general concept of quantum space is given by modifying the original concept defined by Borceux and Bossche. We show that a quantum space is a topological analogue of a quantale defined by Mulvey, and also a non-commutative generalization of the Zariski spectrum of a commutative ring. But quantum spaces are not good enough to have much of the properties of topological spaces, such as product spaces and quotient spaces.

关键词： quantale quantum space Zariski spectrum

Anthrazoline Photocatalyst for Promoting Esterification and Etherification Reactions via Photoredox/Nickel Dual Catalysis

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Chinese Journal of Chemistry 2023年第4期41卷 411-416页

作者： Xiaolin Zhu Qiujin Fan wei luo Danfeng Wang Yihui jia Heyang Li Zhen Wang Qi Xiao Xiaoming He Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education School of Chemistry of Chemical EngineeringShaanxi Normal UniversityXi'anShaanxi710119 China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620 China jiangsu Key Laboratory of Fine Petrochemical Engineering School of Petrochemical EngineeringChangzhou UniversityChangzhouJiangsu213164 China

Here,we demonstrate a readily prepared anthrazoline photocatalyst,which can effectively promote C—O bond formation reactions with the aid of Ni(II)*** methodology enables the esterification(36 examples)and etherification(8 examples)with a broad range of scope,allowing aryl and alkyl halides coupled with diverse carboxylic acids/*** metal-free photocatalysts have a potential broad application,may serve as an alternative to some iridium and ruthenium based photocatalysts,and are of potential importance to the pharmaceutical industry.

关键词： Anthrazoline Photocatalysis Photoredox Cross-coupling C-O bond formation

Skeleton-based Violation Action Recognition Method for Safety Supervision in Operation Field of Distribution Network Based on Graph Convolutional Network

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2179-2187页

作者： Bo Wang Fuqi Ma Rong jia Peng luo Xuzhu Dong the School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China the School of Electrical Engineering Xi’an University of TechnologyXi’an 710054China

Safety accidents in the operation field of the distribution network often occur,which seriously endanger the safety and lives of *** identification methods for safety risk can identify static safety risks,such as no-helmet,no-safety gloves,etc.,but fail to identify risks in the dynamic actions of ***,this paper proposes a skeletonbased violation action-recognition method for supervision of safety during operations in a distribution network,i.e.,based on spatial temporal graph convolutional network(STGCN)and key joint attention module(KJAM),which can implement dynamic violation behavior recognition of *** this method,the human posture estimation method,***-Person Pose Estimation,is utilized to extract the skeleton information of operators during operations,and to construct an undirected graph,which reflects the movement and posture of the human ***,the STGCN is utilized to identify actions of operators that can lead to dynamic *** addition,the KJAM captures important joint information of *** effectiveness and superiority of the proposed method are verified in comparison to other action recognition *** experimental results show that the proposed method has higher recognition accuracy for common violations collected at the actual operation site of the distribution network and shows a strong generalization ability,which can be applied to the video monitoring system of field operations to reduce the occurrence of safety accidents.

关键词： Action recognition graph convolutional network power safety risk power vision safety supervision skeleton information