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Brownian Motion of a Test Particle with a Normal Classical Velocity in Spacetime with a Plane Boundary

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Communications in Theoretical Physics 2007年第5期47卷 847-850页

作者： fu Xiang-yun yu Hong-Wei Department of Physics and Institute of Physics Hunan Normal University Changsha 410081 China

We study the random motion of a charged test particle with a normal classical constant velocity in a spacetime with a perfectly reflecting plane boundary and calculate both the velocity and position dispersions of the test particle. Our results show that the dispersions in the normal direction are weakened while those in the parallel directions are strengthened as compared to the classical static case when the test particle classically moves away from the boundary. However, if the classical motion reverses its direction, then the dispersions in the normal direction are reinforced while those in the parallel directions get weakened.

关键词： Brownian motion vacuum fluctuation quantum field theory

Latitudinal migration of sunspots based on the ESAI database

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Research in Astronomy and Astrophysics 2018年第1期18卷 83-94页

作者： Juan Zhang fu-yu Li Wen Feng yunnan Observatories Chinese Academy of Sciences Kunming 650011 China Research Center of Analysis and Measurement Kunming University of Science and Technology Kunming 650093 China University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China

The latitudinal migration of sunspots toward the equator,which implies there is propagation of the toroidal magnetic flux wave at the base of the solar convection zone,is one of the crucial observational bases for the solar dynamo to generate a magnetic field by shearing of the pre-existing poloidal magnetic field through differential *** Extended time series of Solar Activity Indices（ESAI）elongated the Greenwich observation record of sunspots by several decades in the *** this study,ESAI＇s yearly mean latitude of sunspots in the northern and southern hemispheres during the years 1854 to 1985 is utilized to statistically test whether hemispherical latitudinal migration of sunspots in a solar cycle is linear or *** is found that a quadratic function is statistically significantly better at describing hemispherical latitudinal migration of sunspots in a solar cycle than a linear *** addition,the latitude migration velocity of sunspots in a solar cycle decreases as the cycle progresses,providing a particular constraint for solar dynamo ***,the butterfly wing pattern with a faster latitudinal migration rate should present stronger solar activity with a shorter cycle period,and it is located at higher latitudinal position,giving evidence to support the Babcock-Leighton dynamo mechanism.

关键词： Sun:activity Sun:general Sun:sunspots methods:data analysis

Effective Elastic Properties of 3-Phase Particle Reinforced Composites with Randomly Dispersed Elastic Spherical Particles of Different Sizes Dedicated to Professor Karl Stark Pister for his 95th birthday

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Computer Modeling in Engineering & Sciences 2021年第12期129卷 1305-1328页

作者： yu-fu Ko Jiann-Wen Woody Ju Civil Engineering and Construction Engineering Management California State UniversityLong BeachCA 90840-5101USA Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095-1593USA

Higher-order multiscale structures are proposed to predict the effective elastic properties of 3-phase particle reinforced composites by considering the probabilistic spherical particles spatial distribution,the particle interactions,and utilizing homogenization with ensemble volume average *** matrix material,spherical particles with radius a1,and spherical particles with radius a2,are denoted as the 0th phase,the 1st phase,and the 2nd phase,***,the two inhomogeneity phases are different particle sizes and the same elastic material *** higher-order(in ratio of spherical particle sizes to the distance between the centers of spherical particles)bounds on effective elastic properties of 3-phase particle reinforced proposed Formulation II and Formulation I derive *** a special case,i.e.,particle size of the 1st phase is the same as that of the 2nd phase,the proposed formulations reduce to 2-phase *** theoretical predictions demonstrate excellent agreement with selected experimental *** addition,several numerical examples are presented to demonstrate the competence of the proposed frameworks.

关键词： Particle reinforced composites micromechanics spherical particle interactions ensemble volume average homogenization probabilistic spatial distribution higher-order bounds multiscale

Organic Electrofluorescent Materials Using Pyridine-Containing Macrocyclic Compounds

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维普期刊数据库

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Journal of Materials Science & Technology 2008年第5期24卷 753-756页

作者： Tingxi LI Long fu Wenwen yu Renhe HUANG School of Materials Science and Engineering Shandong University of Science ＆ Technology Qingdao 266510 China

Novel pyridine-containing macrocyclic compounds, such as 6,12,19,25-tetramethyl-7,11,20,24-dinitrilo-dibenzo [b,m]1,4,12,15-tetra-azacyclodoc osine （TMCD）, were synthesized and used as electron transport layer in organic electroluminescent devices. Devices with a structure of glass/indium-tin oxide/arylamine derivative/ tris（quinolinolato）aluminum（Ⅲ）（Alq）/TMCD/LiF/Al exhibited green emission from the Alq layer with external quantum efficiency of 0.84% and luminous efficiency of 1.3 lm/W. The derivatives of TMCD were synthesized and characterized as well. These compounds were also found to be useful as the electron-transporting materials in organic electroluminescent devices.

关键词： Pyridine-containing macrocyclic compound Organic electroluminescent Electron-transporting material

Formation Control for Water-Jet USV Based on Bio-Inspired Method

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China Ocean Engineering 2018年第1期32卷 117-122页

作者： fu Ming-yu WANG Duan-song WANG Cheng-long College of Automation Harbin Engineering University

The formation control problem for underactuated unmanned surface vehicles(USVs) is addressed by a distributed strategy based on virtual leader strategy. The control system takes account of disturbance induced by external environment. With the coordinate transformation, the advantage of the proposed scheme is that the control point can be any point of the ship instead of the center of gravity. By introducing bio-inspired model, the formation control problem is addressed with backstepping method. This avoids complicated computation, simplifies the control law,and smoothes the input signals. The system uniform ultimate boundness is proven by Lyapunov stability theory with Young inequality. Simulation results are presented to verify the effectiveness and robust of the proposed controller.

关键词： water-jet USV bio-inspired model backstepping formation control

Multi-Behavior fusion Based Potential Field Method for Path Planning of Unmanned Surface Vessel

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China Ocean Engineering 2019年第5期33卷 583-592页

作者： fu Ming-yu WANG Sha-sha WANG yuan-hui College of Automation Harbin Engineering University

The problem of the unmanned surface vessel (USV) path planning in static and dynamic obstacle environments is addressed in this paper. Multi-behavior fusion based potential field method is proposed, which contains three behaviors: goal-seeking, boundary-memory following and dynamic-obstacle avoidance. Then, different activation conditions are designed to determine the current behavior. Meanwhile, information on the positions, velocities and the equation of motion for obstacles are detected and calculated by sensor data. Besides, memory information is introduced into the boundary following behavior to enhance cognition capability for the obstacles, and avoid local minima problem caused by the potential field method. Finally, the results of theoretical analysis and simulation show that the collision-free path can be generated for USV within different obstacle environments, and further validated the performance and effectiveness of the presented strategy.

关键词： USV path planning potential field method multi-behavior fusion activation conditions local minima

Biogenic isoprene emissions over China:sensitivity to the CO2 inhibition effect

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Atmospheric and Oceanic Science Letters 2016年第4期9卷 277-284页

作者： fu yu LIAO Hong Climate Change Research Center(CCRC) Chinese Academy of SciencesBeijingChina School of Environmental Science and Engineering Nanjing University of Information Science&TechnologyNanjingChina

Isoprene emissions emitted from vegetation are one of the most important precursors for tropospheric ozone and secondary organic aerosol formation. The authors estimate the biogenic isoprene emissions in China over 2006-2011 using a global chemical transport model （GEOS- Chem） driven by meteorological fields from the assimilated meteorological data from MERRA. The authors incorporate three different parameterizations of isoprene-CO2 interaction into the model, and perform three sensitivity simulations to investigate the effect of CO2 inhibition on isoprene emissions for the period 2006-2011 in China. The annual isoprene emissions rate across China is simulated to be 12.62 Tg C yr-1, averaged over 2006-2011, and decreases by about 2.7%-7.4% when the CO2 inhibition schemes are included. The CO2 inhibition effect might be significant in regions where the CO2 concentration and isoprene emissions are high. Estimates of isoprene emissions can differ depending on the scheme of CO2 inhibition. According to the results obtained from the sensitivity simulations, the authors find that the CO2 inhibition effect leads to 5.6% ±2.3% reductions in annual isoprene emissions over China. The authors also find that inclusion of CO2 inhibition can substantially alter the sensitivity of isoprene emissions to the changes in meteorological conditions during the study period.

关键词： Isoprene emissions C02 inhibition GEOS-Chemmodel

化州柚花浸提液中黄酮成分及其抗氧化活性分析

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农产品加工 2025年第2期 61-65页

作者：刘影杨鑫苏洁如付遇庞富茂名职业技术学院化学工程系广东茂名525000 茂名市橘多宝科技有限公司广东茂名525000

对化州柚花共沸蒸馏浸提液中黄酮类物质进行分析,明确浸提液的应用价值,为化州柚花的多级提取和综合利用提供参考。采用紫外分光光度法测定浸提液中总黄酮的含量,高效液相色谱法测定浸提液中柚皮苷和野漆树苷的含量,通过对DPPH自由基和A... 详细信息

对化州柚花共沸蒸馏浸提液中黄酮类物质进行分析,明确浸提液的应用价值,为化州柚花的多级提取和综合利用提供参考。采用紫外分光光度法测定浸提液中总黄酮的含量,高效液相色谱法测定浸提液中柚皮苷和野漆树苷的含量,通过对DPPH自由基和ABTS+自由基的清除作用评价浸提液的抗氧化活性,并与甲醇提取法进行对比分析。结果表明,蒸馏浸提液中总黄酮的含量虽略低于甲醇提取法,但二者的差异未达到显著水平。蒸馏浸提液中柚皮苷含量和野漆树苷含量均显著低于甲醇提取法。蒸馏浸提液对不同自由基表现出不同的清除能力,对DPPH自由基的清除能力显著高于甲醇提取法,但对ABTS+自由基的清除能力则显著低于甲醇提取法。蒸馏浸提液中总黄酮、柚皮苷、野漆树苷含量与DPPH,ABTS+自由基清除能力均呈显著或极显著的正相关关系。化州柚花共沸蒸馏浸提液中含有丰富的柚皮苷、野漆树苷等黄酮类化合物,有较强的抗氧化活性,具有进一步的应用价值。

关键词：化州柚花总黄酮柚皮苷野漆树苷抗氧化活性

Therapeutic strategies for the costimulatory molecule OX40 in T-cell-mediated immunity

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Acta Pharmaceutica Sinica B 2020年第3期10卷 414-433页

作者： yu fu Qing Lin Zhirong Zhang Ling Zhang Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyCollege of Polymer Science and EngineeringWest China School of PharmacySichuan UniversityChengdu 610064China Department of Pharmacology Yale University School of MedicineNew HavenCT 06510USA

The T cell co-stimulatory molecule OX40 and its cognate ligand OX40 L have attracted broad research interest as a therapeutic target in T cell-mediated *** preclinical evidence highlights the therapeutic efficacy of both agonist and blockade of the OX40-OX40 L *** this progress,many questions about the immuno-modulator roles of OX40 on T cell function remain *** this review we summarize the impact of the OX40-OX40 L interaction on T cell subsets,including Th1,Th2,Th9,Th17,Th22,Treg,Tfh,and CD8+T cells,to gain a comprehensive understanding of anti-OX40 mAb-based *** potential therapeutic application of the OX40-OX40 L interaction in autoimmunity diseases and cancer immunotherapy are further discussed;OX40-OX40 L blockade may ameliorate autoantigen-specific T cell responses and reduce immune activity in autoimmunity *** also explore the rationale of targeting OX40-OX40 L interactions in cancer *** of OX40 with targeted agonist anti-OX40 mAbs conveys activating signals to T *** combined with other therapeutic treatments,such as anti-PD-1 or anti-CTLA-4 blockade,cytokines,chemotherapy,or radiotherapy,the anti-tumor activity of agonist anti-OX40 treatment will be further *** data collectively suggest great potential for OX40-mediated therapies.

关键词： OX40 CD4^+ CD8^+ Treg Autoimmunity diseases Cancer immunotherapy