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Integrated Test System for Large-aperture Telescopes Based on Astrophotonics Interconnections

Instrumentation 2024年第1期11卷 1-9页

作者： Qichang An Kun Wang Xinyue liu hongwen li Jiakang Zhu Changchun Institute of Optical Precision Machinery and Physics Chinese Academy of SciencesChangchunJilin 130033China University of Chinese Academy of Sciences Beijing 100039China Jilin Key Laboratory of Intelligent Wavefront Sensing and Control ChangchunJilin 130033China

This study aims to improve the integrated testing of large-aperture telescopes to clarify the fundamental principles of an integrated testing system based on astrophotonics.Our demonstration and analyses focused on element-position sensing and modulation based on spatial near-geometric beams,high-throughput step-difference measurements based on channel spectroscopy,distributed broadband-transmittance testing,and standard spectral tests based on near-field energy regulation.Comprehensive analyses and experiments were conducted to confirm the feasibility of the proposed system in the integrated testing process of large-aperture telescopes.The results demonstrated that the angular resolution of the light rays exceeded 5arcsec,which satisfies the requirements for component-position detection in future large-aperture telescopes.The measurement resolution of the wavefront tilt was better than 0.45μrad.Based on the channel spectral method—which combined a high signal-to-noise ratio and high sensitivity,along with continuous-spectral digital segmentation and narrowband-spectral physical segmentation—a resolution of 0.050μm and a range of 50μm were obtained.After calibration,the measurement resolution of the pupil deviation improved to exceed 4%accuracy,and the transmission measurements achieved a consistency of over 2%accuracy.Regarding fringe-broadband interferometry measurements,the system maintained high stability,ensuring its operation within the coherence length,and robustly detected the energy without unwrapping the phase.The use of a projector for calibrating broadband-spectrum measurements led to a reduction in contrast from 0.8142 to 0.6038,which further validates the system's applicability in the integrated testing process of large-aperture telescopes.This study greatly enhanced the observational capabilities of large-aperture telescopes while reducing the integrated system's volume,weight,and power consumption.

关键词： curvature sensing wavefront aberration astrophotonics large-aperture telescope

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Experimental study and simulation on the creep characteristics of machineharvested seed cotton

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 241-250页

作者： Ximei Wei hongwen Zhang Jun Wang Shufeng li Lei Wang Xintian Du College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832003XinjiangChina Key Laboratory of Northwest Agricultural Equipment Ministry of AgricultureShihezi 832003XinjiangChina

In view of the unclear understanding of the basic scientific problems such as the rheological mechanism of seed cotton,especially the lack of research on the creep characteristics of seed cotton,the machine-harvested seed cotton in the Xinjiang region was taken as the research object to find out the compression creep characteristics.The universal material testing machine was used to carry out a one-factor creep test,taking moisture content,feed quality,compression times,and trash content as test factors and instantaneous elastic modulus,hysteretic elastic modulus,viscosity coefficient,and delay time as test indicators.The ANOVA and correlation were analyzed by SPSS,and the creep process of the seed cotton was simulated by ADAMS.Results show that moisture content significantly affects the instantaneous elastic modulus,hysteretic elastic modulus,and viscosity coefficient(plity significantly affects the hysteretic elastic modulus and viscosity coefficient(plity.The compression times significantly influence the instantaneous elastic modulus,hysteretic elastic modulus,and viscosity coefficient(plity of cotton bale(mold).

关键词： creep characteristics machine-harvested seed cotton analysis of ANOVA one-factor tests ADAMS

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Novel de novo TRPV4 mutation identified in a Chinese family with metatropic dysplasia inhibits chondrogenic differentiation

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Genes & Diseases 2024年第3期11卷 83-86页

作者： Ping Wei Weizhe Shi Tianying Nong Caixia Xian Xia li Zhaohui li Xin li Jianping Wu liyuan Shang Fulong Xu Yibo Xu hongwen Xu Mingwei Zhu Guangzhou Institute of Pediatrics Guangzhou Women and Children's Medical CenterGuangzhou Medical UniversityGuangdong Provincial Clinical Research Center for Child HealthGuangzhouGuangdong 510623China Department of Pediatric Orthopedics Guangzhou Women and Children's Medical CenterGuangzhou Medical UniversityGuangdong Provincial Clinical Research Center for Child HealthGuangzhouGuangdong 510623China

Metatropicdysplasia(MD,MIM156530)is a rare congenital bone dysplasia primarily characterized by severe platyspondyly with long and wide vertebral bodies and dumbbell deformity of the tubular bones.MD can be caused by heterozygous mutations in the gene encoding transient receptor potential vanilloid family member 4(TRPV4).We identifieda novel de novo mutation,c.2353T>C,in the TRPV4 gene,in a Chinese family with mild MD.

关键词： TRPV4 dysplasia congenital

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Design and experiment of pneumatic seed clearing mechanism for pin-hole tube wheat plot precision sowing device

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 85-95页

作者： Xirui Zhang Youming Yang Qingjie Wang hongwen li Zhifu Zhang Junxiao liu School of Mechanical and Electrical Engineering Hainan UniversityHaikou 570228China College of Engineering China Agricultural UniversityBeijing 100083China Sanya Nanfan Research Institute of Hainan University Sanya 572025HainanChina

For the problem that when wheat is sucked up by the air suction method,the seeds are aligned in a small area,making it difficult for the contact seed cleaning mechanism to clean the seeds.The mechanism of seed cleaning airflow on wheat seed was studied,the flow velocity distribution relationship of the jet section was defined,the mathematical model of the jet velocity of circular and plane sections was established,and the key factors that could have a significant influence on seed cleaning effect were explored.A non-contact positive pressure air flow seed cleaning method was proposed.After theoretical calculations,it is concluded that the core section lengths of the circular section jet and the inline jet are 24.8 mm and 28.8 mm,respectively.The clearing distance is set to 20 mm.Through the single-factor test,the best air tube nozzle shape was clarified as a vertical inline nozzle.The angle of seed cleaning,the air velocity of seed cleaning,and the negative supply pressure were selected as influencing factors,and the seed leakage index,seed reabsorption index,and seed qualification index as the evaluation indicators to conduct a 3-factor 5-horizontal rotation test.A mathematical regression model of influencing factors and evaluation indexes was established to analyze the influence of these factors and indexes.The optimal operation parameters were obtained as the seed cleaning Angle of 19°,the seed cleaning air velocity of 58 m/s,and the negative pressure of 8.5 kPa.Under the optimal parameters,the seed leakage suction index is 8.23%,the seed reabsorption index is 0.33%,and the seed qualification index is 91.44%,which meets the design requirements.

关键词： wheat precision seed-metering device clearing seed positive pressure airflow jet flow field

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Design and experiment of the pneumatic pressure control device for no-till planter

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International Journal of Agricultural and Biological Engineering 2023年第3期16卷 37-46页

作者： Xinpeng Cao Qingjie Wang hongwen li Jin He Caiyun Lu Dijuan Xu Xiuhong Wang College of Engineering China Agricultural UniversityBeijing 100083China Cultivated Land Conservation Agricultural Science Observation and Experiment Station Northern Hebei ProvinceMinistry of Agriculture and Rural AffairsBeijing 100083China Beijing Vocational College of Agriculture Beijing 100083China

An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistency of seeding depth can be caused by the pressure fluctuation of the coil-spring pressure control device(CPCD)when the no-till planter is working on the unplowed ground.In this study,a pneumatic pressure control device(PPCD)was designed for the no-till planter,the key structural parameters of air spring for press wheel pressure(PWP)stability were determined by theoretical analysis and parameter calculation.Using the gas-structure coupling finite element simulation method(FESM),the piston radius,piston angle,and cord angle of the air spring are selected as the test factors,and the vertical stiffness was used as the test index to carry out the quadratic rotation orthogonal combination test to establish the regression model of test index and factor.The bench test of the PPCD was carried out under the optimal parameter combination,piston radius of 27.2 mm,piston angle of 11.7°,and cord angle of 30.0°.The vertical stiffness verification test showed that the simulation test was consistent with the bench test result,the vertical stiffness simulation error was 7.1%,and the internal air pressure simulation error was 3.0%;The control response test showed that the average response time of the air spring inflating and deflating was 0.80 s,the maximum overshoot was 4.33%during inflation,and no pressure overshoot during deflation;Under the condition of-40-40 mm surface relief height,the PPCD could effectively reduce the pressure fluctuation compared with the CPCD,and the average reduction of the pressure fluctuation was about 25.1%.

关键词： air spring no-till planter pressure control finite element analysis

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传道授业解惑:医学伦理学究竟教什么?

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医学与哲学 2024年第6期45卷 11-14页

作者：李红文湖南中医药大学马克思主义学院湖南长沙410208

医学伦理学课程究竟传的是什么“道”、授的是什么“业”、解的是什么“惑”?这是医学伦理学教学的元问题。根据其学科性质,主要存在四种不同的教学模式,分别是知识型、技能型、观念型和美德型。这四种模式既有其各自的优点,也有其弊端... 详细信息

医学伦理学课程究竟传的是什么“道”、授的是什么“业”、解的是什么“惑”?这是医学伦理学教学的元问题。根据其学科性质,主要存在四种不同的教学模式,分别是知识型、技能型、观念型和美德型。这四种模式既有其各自的优点,也有其弊端和不足。它们都从某个侧面反映了医学伦理学某个方面的属性和特征,但都难以涵盖整个学科的全貌。在实践教学中,不能采用单一的教学模式而忽略其他维度的存在,最有效的策略是选择综合性的授课方式,帮助医生构建完整的伦理知识体系,有效解决临床实践中的道德难题。

关键词：医学伦理学教学模式伦理知识实践技能医学美德

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多镜面大视场主动光学望远镜调控方法

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光学精密工程 2024年第6期32卷 785-791页

作者：安其昌吴小霞唐境李洪文中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100039 吉林省智能波前传感与控制重点实验室吉林长春130033

为了更好地实现多镜面大视场主动光学望远镜波前像差抑制、提升望远镜探测能力极限,本文基于望远镜视场边缘内置的错位型曲率传感器进行波前感知,并利用功率谱对波前感知结果进行分析,进而基于波前像差的空间频率特征进行调控。首先,基... 详细信息

为了更好地实现多镜面大视场主动光学望远镜波前像差抑制、提升望远镜探测能力极限,本文基于望远镜视场边缘内置的错位型曲率传感器进行波前感知,并利用功率谱对波前感知结果进行分析,进而基于波前像差的空间频率特征进行调控。首先,基于复光场理论分析了非瞳面对系统波前调控的影响机理。其次,分析了本方法在多镜面大视场主动光学望远镜调控过程中的精度特性。再次,利用桌面实验对多镜面大视场主动光学望远镜调控的可行性进行了验证。最终,波前重建结果与理论波前相关性高于0.85。利用功率谱对各个视场的空间频率特性进行了分析,与单纯使用均方根对多镜面影响敏感度进行分析的方法相比,灵敏度提升了20%。

关键词：曲率传感波前像差大视场主动光学大口径望远镜

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镁硅比和养护温度对硅酸镁水泥电磁性能的影响

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建筑材料学报 2024年第2期27卷 139-145页

作者：李悦李洪文金彩云林辉罗晓北京工业大学重庆研究院重庆401121 北京工业大学城市建设学部北京100124 北京工业大学理学部北京100124

采用波导法测定硅酸镁水泥的电磁性能,分析镁硅比和养护温度的影响,并基于微观测试结果进行机理分析.结果表明:提高养护温度可以显著增强硅酸镁水泥的早期强度;硅酸镁水泥的复介电常数实部随着镁硅比和养护温度的提高逐渐增大;提高养护... 详细信息

采用波导法测定硅酸镁水泥的电磁性能,分析镁硅比和养护温度的影响,并基于微观测试结果进行机理分析.结果表明:提高养护温度可以显著增强硅酸镁水泥的早期强度;硅酸镁水泥的复介电常数实部随着镁硅比和养护温度的提高逐渐增大;提高养护温度使硅酸镁水泥的复介电常数虚部和损耗角正切值增大;与镁硅比相比,养护温度对硅酸镁水泥的透射率、反射率和吸收率的影响更为明显.微观测试结果显示含水量和孔结构对硅酸镁水泥的电磁性能有重要影响.

关键词：硅酸镁水泥镁硅比养护温度电磁性能

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Design and experiment of seed furrow cleaning device based on throwing and sliding for no-till maize seeding

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International Journal of Agricultural and Biological Engineering 2022年第4期15卷 95-102页

作者： Panpan Yuan hongwen li Caiyun Lu Qingjie Wang Jin He Shenghai Huang Dandan Cui College of Engineering China Agricultural UniversityBeijing 100083China College of Mechanical and Electrical Engineering Xinjiang Agricultural UniversityUrumqi 830052China Key Laboratory of Agricultural Equipment for Conservation Tillage Ministry of Agricultural and Rural AffairsBeijing 100083China

In order to solve the serious problems of seeds are covered by residual film and overhead by straw during no-till seeding,a seed furrow cleaning device for no-till maize seeding was developed,which adopted a collaborative cleaning method of rotating spring teeth and curved sliding shovel.The movement process and motion trajectory of throwing residual film and straw were constructed.The maximum distance of throwing to one side in horizontal and maximum height in vertical were obtained.The motion trajectory of adjacent spring teeth was analyzed by Matlab,the motion trajectories of adjacent spring teeth at different speeds of 120 r/min,150 r/min and 180 r/min were achieved,the theoretical analysis results showed that the area of omitted area decreased with the increase of rotation speed.Based on theoretical and simulation analysis of critical parameters,the forward speed of machine,rotation speed of spring teeth,and dip angle between spring teeth and rotary disc were selected as the influencing factor.Straw cleaning rate(SCR)and residual film cleaning rate(RFCR)were selected as the response values for three factors and three levels of orthogonal experiment design.The optimal combination of the selected parameters was obtained,and the field test verification was also conducted.The results showed that the rotation speed of spring teeth,forward speed and dip angle of spring teeth significantly affect SCR and RFCR were in decreasing order.The field test results indicated that when forward speed was 6 km/h,rotation speed of spring teeth was 180 r/min and dip angle of spring teeth was 40°,SCR and RFCR were 88.27%and 84.31%,respectively.This study provides a reference for the development of no-till seeder in Xinjiang and the northwestern regions of China.

关键词： maize conservation tillage no-till seeding seed furrow cleaning straw residual film

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电催化二氧化碳还原用铜基催化剂设计策略

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洁净煤技术 2024年第4期30卷 41-57页

作者：郑逸群李敦闵媛媛李雨窈黄宏文济宁学院化学化工与材料学院山东曲阜273155 湖南大学材料科学与工程学院湖南长沙410082

随着全球经济增长,对能源需求不断攀升,进而推动了能源的开发与利用,不可避免导致CO_(2)排放量的持续上升。为有效应对这一环境挑战,电催化CO_(2)还原(CO_(2)RR)技术应运而生,并迅速成为研究热点。该技术不仅可将CO_(2)转换为燃料和化学... 详细信息

随着全球经济增长,对能源需求不断攀升,进而推动了能源的开发与利用,不可避免导致CO_(2)排放量的持续上升。为有效应对这一环境挑战,电催化CO_(2)还原(CO_(2)RR)技术应运而生,并迅速成为研究热点。该技术不仅可将CO_(2)转换为燃料和化学品,而且有助于实现可再生能源储存。在众多催化剂中,铜基催化剂因其能高效将CO_(2)直接转化为高价值多碳化学品(如乙烯和乙醇)而受到关注。近年来,铜基CO_(2)RR催化剂优化设计进展显著,主要集中在提高催化活性、选择性和稳定性上。重点综述了近年来电催化CO_(2)RR用铜基催化剂的优化设计策略研究进展。从调控催化活性和选择性以及稳定性2方面,分别讨论了晶面工程、合金化处理、铜氧化态调节、催化剂表面功能化和缺陷工程等代表性调控策略的研究进展,探讨了电催化剂的核心参数(组成、微观结构、形貌、尺寸等)对催化剂性能的协同效应。最后对未来电催化CO_(2)RR技术的发展前景进行展望,并分析当前面临的挑战。

关键词：二氧化碳电化学还原电催化剂铜基催化剂纳米晶体合成改性高值化学品

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