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Image motion and experimental study of a 0.1″space pointing measuring instrument for micro-vibration conditions

Chinese Journal of Aeronautics 2023年第2期36卷 191-200页

作者： Lin LI Li YUAN Li WANG Miaomiao WANG Xiaoxue GONG Jie SUI Yanpeng Wu Ran ZHENG Space Optoelectronic Measurement and Perception Lab. Beijing Institute of Control EngineeringBeijing 100190China China Academy of Space Technology Beijing 100094China Science and Technology on Space Intelligent Control Laboratory Beijing 100094China University of Chinese Academy of Sciences Beijing 100049China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Chang Guang Satellite Technology Co. Ltd.Changchun130102China

There exists an increasing need for Milli-Arc-Seconds(MAS)accuracy pointing measurement for current and future space systems.To meet the 0.1″space pointing measurement accuracy requirements of spacecraft in future,the influence of spacecraft micro-vibration on a 0.1″Space Pointing Measuring Instrument(SPMI)is studied.A Quasi-Zero Stiffness Device(QZSD)with adaptive adjustment and variable stroke was proposed.Then,a series of micro-vibration experiments of the SPMI were carried out.The influence of the micro-vibration generated by Guidance Navigation Control(GNC)attitude control components under different attitudes on the SPMI was analyzed.Point spread function of image motion in micro-vibration was also derived.Further,the changes of image motion under the micro-vibration environment were evaluated by extracting the gray centroid of the images,and the experiment processes and results are deeply discussed.The results show that the firstorder frequency of the QZSD system is 0.114 Hz,and it is induced by a double pendulum system;the image motion of single flywheel spinning reached 0.015 pixels;whilst the image motion reached 0.03 pixels when three flywheels are combined spinning.These latest findings provide a beneficial theoretical and technical support for the development of spacecraft with 0·1″pointing accuracy.

关键词： Image motion Micro-vibration Milli-arc-seconds Quasi-zero stiffness device Space pointing measuring instrument

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Recent advances in precision measurement & pointing control of spacecraft

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Chinese Journal of Aeronautics 2021年第10期34卷 191-209页

作者： Lin LI Li YUAN Li WANG Ran ZHENG Yanpeng Wu Xiaoyan WANG Space Optoelectronic Measurement and Perception Lab. Beijing Institute of Control EngineeringBeijing 100190China Science and Technology on Space Intelligent Control Laboratory Beijing 100094China China Academy of Space Technology Beijing 100094China

There exists an increasing need for precision measurement&pointing control and extreme motion stability for current and future space systems,e.g.,Ultra-Performance Spacecraft(UPS).Some notable technologies of realizing Ultra-Pointing(UP)ability have been developed particularly for Ultra-accuracy Ultra-stability Ultra-agility(3 U)spacecraft over recent decades.Usually,Multilevel Compound Pointing Control Techniques(MCPCTs)are deployed in aerospace engineering,especially in astronomical observation satellites and Earth observation satellites.Modern controllers and/or algorithms,which are a key factor of MCPCTs for 3 U spacecraft,especially the jitter phenomena that commonly exist in a UPS Pointing Control System(PCS),have also been effectively used in some UP spacecraft for a number of years.Micro-vibration suppression approaches,however,are often proposed to deal with low-level mechanical vibration or disturbance in the microgravity environment that is common for UPS.This latter approach potentially is one of the most practical UP techniques for 3 U tasks.Some emerging advanced Disturbance-Free Payload(DFP)satellites that exploit the benefits of non-contact actuators have also been reported in the literature.This represents an interesting and highly promising approach for solving some challenging problems in the area.This paper serves as a state-of-the-art review of UP technologies and/or methods which have been developed,mainly over the last decade,specifically for or potentially could be used for 3 U spacecraft pointing control.The problems discussed in this paper are of reference significance to UPS and millisecond optical sensors,which are involved in Gaofeng Project,deep space exploration,manned space flight,and gravitational wave detection.

关键词： Disturbance-free payload Micro-vibration suppression Modern controllers or algorithms Pointingcontrol system Ultra-performance spacecraft

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Mechanisms of isomerization and hydration reactions of typicalβ-diketone at the air-droplet interface

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Journal of Environmental Sciences 2024年第7期141卷 225-234页

作者： Yuemeng Ji Weiyong Luo Qiuju Shi Xiaohui Ma Ziqi wu Weina Zhang yanpeng Gao Taicheng An Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health Guangdong Key Laboratory of Environmental Catalysis and Health Risk ControlInstitute Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of EducationSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Acetylacetone(AcAc)is a typical class ofβ-diketones with broad industrial applications due to the property of the keto-enol isomers,but its isomerization and chemical reactions at the air-droplet interface are still unclear.Hence,using combined molecular dynamics and quantum chemistry methods,the heterogeneous chemistry of AcAc at the air-droplet interface was investigated,including the attraction of AcAc isomers by the droplets,the distribution of isomers at the air-droplet interface,and the hydration reactions of isomers at the air-droplet interface.The results reveal that the preferential orientation of two AcAc isomers(keto-and enol-AcAc)to accumulate and accommodate at the acidic air-droplet interface.The isomerization of two AcAc isomers at the acidic air-droplet interface is more favorable than that at the neutral air-droplet interface because the“water bridge”structure is destroyed by H_(3)O^(+),especially for the isomerization from keto-Ac Ac to enol-AcAc.At the acidic air-droplet interface,the carbonyl or hydroxyl O-atoms of two AcAc isomers display an energetical preference to hydration.Keto-diol is the dominant products to accumulate at the air-droplet interface,and excessive keto-diol can enter the droplet interior to engage in the oligomerization.The photooxidation reaction of AcAc will increase the acidity of the air-droplet interface,which indirectly facilitate the uptake and formation of more keto-diol.Our results provide an insight into the heterogeneous chemistry ofβ-diketones and their influence on the environment.

关键词： Acetylacetone Air-droplet interface Theoretical simulation Isomerization Hydration reaction mechanism

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A Retrospective Modeling Study of the Targeted Non-Pharmaceutical Interventions During the Xinfadi Outbreak in the Early Stage of the COVID-19 Pandemic — Beijing, China, 2020

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China CDC weekly 2023年第5期5卷 108-112,I0007-I0011页

作者： Yan Wang Kaiyuan Sun Yang Pan Lan Yi Da Huo Yanpeng Wu Shuaibing Dong Jinxin Guo Xiangfeng Dou Wei Wang Shuangsheng wu Xufang Bai Hongjie Yu Quanyi Wang School of Public Health Fudan UniversityKey Laboratory of Public Health SafetyMinistry of EducationShanghai MunicipalityChina Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA Beijing Center for Disease Prevention and Control Beijing MunicipalityChina Shanghai Institute of Infectious Disease and Biosecurity Fudan UniversityShanghai MunicipalityChina

Summary What is already known about this topic?China has repeatedly contained multiple severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)outbreaks through a comprehensive set of targeted nonpharmaceutical int... 详细信息

关键词： acute respiratory assessed

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Study on the method of precision adjustment of star sensor

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Nanotechnology and Precision Engineering 2018年第4期1卷 248-257页

作者： Xiaoyan Wang Ran Zheng Yanpeng Wu Jianbo Sun Jun Zhong Long Wang Miaomiao Wang Beijing Institute of Control Engineering Beijing 100190China

Star sensors are indispensable spatial measurement sensors for high-resolution earth observation and astronomical observations, and the demand for high measurement accuracy of satellite sensors continues to increase; thus, the star sensor optical machine adjustment error cannot be ignored. The commonly used installation error correction method cannot solely meet the precision analysis requirements. In this paper, the relationship between the optical machine installation and the star sensor measurement error is analyzed, and several common adjustment error correction methods are compared. An adjustment method for optical machines is proposed to meet the requirements of very high precision star sensors. The assembly precision requirements of the investigated very high precision star sensor are analyzed considering the whole machine, and then the optical components are controlled through optical precision adjustments to satisfy the precision requirements. Finally, through the complete machine calibration, the star sensor precision adjustment for an optical machine structure is verified. This method meets the requirements of very high precision sensors and is suitable for the precision adjustment of optical machine structures, which is of practical significance to improve the precision of star sensors.

关键词： Very high precision star sensor Optical machine structure Alignment precision Precision adjustment

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Transmission Dynamics and Epidemiological Characteristics of the SARS-CoV-2 Delta Variant ― Hunan Province, China, 2021

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China CDC weekly 2023年第3期5卷 56-62,I0006-I0009页

作者： Kaiwei Luo Yanpeng Wu Yan Wang Ziyan Liu Lan Yi Shanlu Zhao Xuemei Yan Hao Yang Kaiyuan Sun Marco Ajelli Shixiong Hu Hongjie Yu Hunan Provincial Center for Disease Control and Prevention Workstation for Emerging Infectious Disease Control and PreventionChinese Academy of Medical SciencesChangsha CityHunan ProvinceChina Shanghai Institute of Infectious Disease and Biosecurity Fudan UniversityShanghai MunicipalityChina School of Public Health Fudan UniversityKey Laboratory of Public Health SafetyMinistry of EducationShanghai MunicipalityChina Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA Laboratory of Computational Epidemiology and Public Health Department of Epidemiology and BiostatisticsIndiana University School of Public HealthBloomingtonINUSA

Monitoring changes in the epidemiologic features between different severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants is key to understanding the evolution of viral fitness in the host population.Here,we analyzed a successfully contained local outbreak of the Delta variant that took place in Hunan,China,in July–August,2021.Detailed data on SARS-CoV-2 infections and their contacts were collected during the outbreak.By leveraging these data,we estimated key epidemiological parameters,including the incubation period,serial interval,and generation time.We constructed a generalized linear mixed-effects model(GLMM)to quantify risk factors for Delta infection and transmission.Between July 28 and August 15,2021,a total of 129 infections and their 2,118 close contacts were identified during the outbreak in Hunan Province.

关键词： Hunan population Province

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Gold nanorods and nanohydroxyapatite hybrid hydrogel for preventing bone tumor recurrence via postoperative photothermal therapy and bone regeneration promotion

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Bioactive Materials 2021年第8期6卷 2221-2230页

作者： Jinfeng Liao Kun Shi yanpeng Jia Yanting wu Zhiyong Qian State Key Laboratory of Oral Diseases National Clinical Research Centre for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengdu610041P.R.China State Key Laboratory of Biotherapy State Key Laboratory and Collaborative Innovation Center of BiotherapyWest China HospitalSichuan UniversityChengdu610041SichuanP.R.China

Osteosarcoma is a malignant bone tumor,which often occurs in adolescents.However,surgical resection usually fails to completely remove the tumor clinically,which has been the main cause of postoperative recurrence and metastasis,resulting in the high death rate of patients.At the same time,osteosarcoma invades a large area of the bone defect,which cannot be self-repaired and seriously affects the life quality of the patients.Herein,a bifunctional methacrylated gelatin/methacrylated chondroitin sulfate hydrogel hybrid gold nanorods(GNRs)and nanohydroxyapatite(nHA),which possessed excellent photothermal effect,was constructed to eradicate residual tumor after surgery and bone regeneration.In vitro,K7M2wt cells(a mouse bone tumor cell line)can be efficiently eradicated by photothermal therapy of the hybrid hydrogel.Meanwhile,the hydrogel mimics the extracellular matrix to promote proliferation and osteogenic differentiation of mesenchymal stem cells.The GNRs/nHA hybrid hydrogel was capable of photothermal treatment of postoperative tumors and bone defect repair in a mice model of tibia osteosarcoma.Therefore,the hybrid hydrogel possesses dual functions of tumor therapy and bone regeneration,which shows great potential in curing bone tumors and provides a new hope for tumor-related bone complex disease.

关键词： Bone tumor Gold nanorods Hybrid hydrogel Photothermal therapy Bone regeneration

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Effect of Retained Austenite on Corrosion Behavior of Ultrafine Bainitic Steel in Marine Environment

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Acta Metallurgica Sinica(English Letters) 2023年第5期36卷 717-731页

作者： Xian Zhang Li Gong yanpeng Feng Zhihui Wang Miao Yang Lin Cheng Jing Liu Kaiming wu Hubei Province Key Laboratory of Systems Science in Metallurgical Process The State Key Laboratory of Refractories and MetallurgyCollaborative Innovation Center for Advanced SteelsWuhan University of Science and TechnologyWuhan430081China School of Chemistry Chemical Engineering and Life SciencesWuhan University of TechnologyWuhan430070China

In this study,the impact of retained austenite on corrosion initiation,propagation,and resistance of ultrafine bainitic steels in marine environments based on the one-step and two-step bainitic isothermal transformation was investigated using a combination of theoretical calculations and experimental methods.According to the results,the microstructure of ultrafine bainitic steels was composed of parallel arranged bainite ferrite(BF)and retained austenite(RA).The fraction of the block RA was significantly reduced,whereas the amount of the film RA increased through the two-step bainitic transformation.In the initial stage of corrosion,micro-galvanic effects occurred between the multiphases due to the difference in nobility,leading to the selective dissolution of BF sheaves,which is adjacent to the block RA in the one-step bainitic steel.However,uniformly distributed film RA in the two-step bainitic steel acted as a barrier against corrosion propagation.The electrochemical measurements and neutral salt spray tests revealed a relatively lower corrosion rate for the two-step bainitic steel,indicating a higher corrosion resistance than the one-step bainitic steel.The corrosion products layer mainly consisted ofα-FeOOH,γ-FeOOH,and Fe_(3)O_(4),which were stable and favorable for the formation of a protective rust layer.

关键词： Ultrafine bainitic steel Retained austenite Marine environment Corrosion behavior First principle modeling

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Effects of imperfect experimental conditions on stress waves in SHPB experiments

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Acta Mechanica Sinica 2015年第6期31卷 827-836页

作者： Xianqian wu Qiuyun Yin yanpeng Wei Chenguang Huang Key Laboratory of Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences

Experimental and numerical simulations were undertaken to estimate the effects of imperfect conditions on stress waves in split Hopkinson pressure bar （SHPB） experiments. The photonic Doppler velocimetry （PDV） measurement results show that the rise and fall times of an incident wave increases with an increasing inclination angle; also, the fluctuations of the incident wave disappear gradually with the increase of inclination angle. The following characteristics for various defects in the SHPB were obtained by numerical simulation：（1） the influence of a curved bar was negligible; （2） misalignment modestly affects the fluctuation characteristics, and bending waves were generated at this condition; （3） inclination and indentation of the impact end- surface had a great impact on the incident waves, and both of them increase the rise time of the incident wave by increasing the degree of defects. In view of the results, misalignment, inclination, and indentation in SHPB experiments should be minimized.

关键词： Imperfect experimental conditions SHPBexperiments Stress waves PDV measurement. Numericalsimulation

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Cell Membrane-camouflaged Multi-functional Dendritic Large Pore Mesoporous Silica Nanoparticles for Combined Photothermal Therapy and Radiotherapy of Cancer

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Chemical Research in Chinese Universities 2022年第2期38卷 562-571页

作者： wu Liting XIN Yujia GUO Zhaoyang GAO Wei ZHU yanpeng WANG Yinsong RAN Ruixue YANG Xiaoying Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics(Theranostics) School of PharmacyTianjin Medical UniversityTianjin 300070P.R.China

Combining photothermal therapy and radiotherapy(PTT-RT) with reducing tumor hypoxia acts as an important antitumor modality. However, it is a great challenge to realize photothermal therapy, radiotherapy and exogenous oxygen supply in one nanosystem. To realize a combination of the three functions, we fabricated a red blood cell membrane(RBCm)-camouflaged, red blood cell content(RBCc) and the copper sulfide(CuS) co-loaded dendritic large pore mesoporous silica nanoparticle(DLMSN/CuS/RBCc/ RBCm). The cell membrane coating endowed the nanoparticles with good stability in the physiological environment, and CuS allowed the nanoparticle exhibiting good photothermal and radiosensitization properties. RBCc loaded nanoparticle DLMSN/CuS/RBCc enhanced superior anti-tumor effect than DLMSN/CuS during combined PTT-RT therapy because the introduction of RBCc increased the exogenous oxygen supply. The in vitro study further demonstrated that the combination of photothermal therapy and radiotherapy induced superior antitumor efficacy than single therapy. Our work thus presents a unique multifunctional nanoscale platform favorable for combined PTT and RT.

关键词： Dendritic large pore mesoporous silica nanoparticle Photothermal therapy Radiosensitization Red blood cell membrane Oxygen carrying

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