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Gravitational Deformation Measurement Method for the Main Reflector and Sub-reflector of the 70 m Antenna by Laser Scanner

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Research in Astronomy and Astrophysics 2022年第9期22卷 1-9页

作者： Lian-Bo Fu jian-jun liu Wei Yan De-Qing Kong Xin Ren Chen-Di liu Hong-Bo Zhang Key Laboratory of Lunar and Dep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBejing 100101China Urunaivreyr of Chinese Academy of Sciences Beijing 100049China

Large antennas play an important role in deep space exploration and astronomical research. However, their performances are inevitably affected by the main reflector surface deformation and sub-reflector displacement resulting from the factors of wind, temperature, and gravity, among which the effect of gravity is especially pronounced. In this work, a three-dimensional laser scanner was employed to measure the main reflector and subreflector gravitational deformation of the Tianjin 70 m antenna at different elevation angles. Here, we solved the antenna main reflector deformation and sub-reflector displacement, and analyzed the deformation law of the antenna under the action of gravity. A new measurement method of antenna main reflector deformation and subreflector displacement is realized by mutual verification of the measured results and theoretical simulations. This method will help to improve the antenna performance and provide a reference to optimize the design of largeaperture antennas.

关键词： telescopes techniques:radar astronomy planets and satellites:detection

Two-layer Lagrange-based relay network topology and trajectory design for solar system explorations

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Science China(Information Sciences) 2024年第6期67卷 342-358页

作者： jun CAO jian JIAO Hao liu Rongxing LU Qinyu ZHANG Guangdong Provincial Key Laboratory of Aerospace Communication and Networking Technology Harbin Institute of Technology (Shenzhen) Faculty of Computer Science (FCS) University of New Brunswick

Exploration targeting outer planets and even the edge of the solar system is an emerging direction for the deep-space exploration in the next decades. To address this challenge, a novel two-layer Lagrangebased relay network topology is proposed in this study. Specifically, we utilize the Sun-Mars and Sun-Saturn Lagrange points(LPs) L4 and L5 to build a two-layer backbone relay network, which ensures continuous and high-efficiency communication capability for the exploration of the solar system. Furthermore, we utilize the planetary gravity assist and design the transfer trajectory of backbone relays with the help of planetary celestial body motion equations and Kepler's laws. Moreover, we conduct link budget analysis for multihop relay transmission under Gamma-Gamma distribution, shadowed Rician fading, and additive white Gaussian noise channels in several typical exploration scenarios and validate that the LP relays can effectively support future deep-space exploration missions.

关键词： deep-space communication Lagrangian points backbone relay network transfer trajectory relay selection

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BaCe_(0.8)Fe_(0.1)Ni_(0.1)O_(3−δ)-impregnated Ni-GDC by phase-inversion as an anode of solid oxide fuel cells with on-cell dry methane reforming

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Journal of Advanced Ceramics 2024年第6期13卷 834-841页

作者： Yanya liu jun Luo Cheng Li Bo liu Dong Yan jian Li Lichao Jia School of Materials Science and Engineering State Key Laboratory of Materials Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074China

BaCe_(0.8)Fe_(0.1)Ni_(0.1)O_(3−δ)(BCFN)in a perovskite structure is impregnated consecutively by BCFN solution and BCFN suspension into a phase-inversion prepared NiO–Gd_(0.1)Ce_(0.9)O_(2−δ)(GDC)scaffold as an anode for solid oxide fuel cells(SOFCs)with on-cell dry reforming of methane(DRM).The whole pore surface of the scaffold is covered by small BCFN particles formed by BCFN solution impregnation;the large pores near the scaffold surface are filled by BCFN aerogels with a high specific surface area produced by BCFN suspension impregnation,which act as a catalytic layer for on-cell *** reduction,the anode consists of a Ni–GDC scaffold and BCFN particles with exsolved FeNi3 *** BCFN-impregnated Ni–GDC anode has higher electrical conductivity,electrochemical activity,and resistance to carbon deposition,with which the cell shows maximum power densities between 1.44 and 0.92 W·cm^(−2) when using H_(2) and between 1.09 and 0.50 W·cm^(−2) when using CO_(2)–CH_(4) at temperatures ranging from 750 to 600℃.A stable performance at 400 mA·cm^(−2) and 700℃is achieved using 45%CO_(2)–45%CH_(4)–10%N_(2) for more than 400 h without carbon deposition,benefiting from the impregnated BCFN aerogel with a high specific surface area and water adsorbability.

关键词： aerogel solid oxide fuel cells(SOFCs) phase-inversion dry reforming of methane(DRM) carbon resistance

The mechanism of Yinchenhao decoction in treating obstructivejaundice- induced liver injury based on Nrf2 signaling pathway

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World Journal of Gastroenterology 2022年第32期28卷 4635-4648页

作者： jun-jian liu Yan Xu Shuai Chen Cheng-Fei Hao Jing Liang Zhong-Lian Li The Second Department of Hepatobiliary and Pancreatic Surgery Tianjin Medical University NanKai HospitalTianjin 300102China Graduate School Tianjin Medical UniversityTianjin 3000070China Department of Thoracic Surgery Xuzhou City Hospital of Traditional Chinese MedicineXuzhou 221000Jiangsu ProvinceChina School of Foreign Languages Chengdu University of Traditional Chinese MedicineChengdu 610000Sichuan ProvinceChina

BACKGROUND Obstructive jaundice(OJ)is caused by bile excretion disorder after partial or complete bile duct *** may cause liver injury through various *** Chinese medicine(TCM)has a lot of advantages in treating *** recovery of liver function can be accelerated by combining Chinese medicine treatment with existing clinical *** decoction(YCHD),a TCM formula,has been used to treat *** much progress has been made in recent years in understanding the mechanism of YCHD in treating OJ-induced liver injury,it is still not *** To investigate chemical components of YCHD that are effective in the treatment of OJ and predict the mechanism of *** The active components and putative targets of YCHD were predicted using a network pharmacology *** Ontology biological process and Kyoto Encyclopedia of Genes and Genomes path enrichment analysis were carried out by cluster *** predicted the biological processes,possible targets,and associated signaling pathways that YCHD may involve in the treatment of *** male Sprague–Dawley rats were randomly divided into three groups,each consisting of 10 rats:the sham group(Group S),the OJ model group(Group M),and the YCHDtreated group(Group Y).The sham group only received *** OJ model was established by ligating the common bile duct twice in Groups M and *** 1 wk,rats in Group Y were given a gavage of YCHD(3.6 mL/kg)twice daily,whereas rats in Groups S and M were given the same amount of physiological saline after intragastric administration *** 7 d,all rats were killed,and the liver and blood samples were collected for histopathological and biochemical *** bilirubin(TBIL),direct bilirubin(DBIL),alanine aminotransferase(ALT),and aspartate transaminase(AST)levels in the blood samples were *** gene expression levels of inducible nitric oxide synthase(iNOS)and endothelial nitric oxide synthase(eNOS),and th

关键词： Yinchenhao decoction Obstructive jaundice Network pharmacology Liver injury Animal models Oxidative stress

The New Wuqing 70 m Radio Telescope and Measurements of Main Electronic Properties in the X-band

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Research in Astronomy and Astrophysics 2022年第3期22卷 122-132页

作者： De-Qing Kong Chun-Lai Li Hong-Bo Zhang Yan Su jian-jun liu Xin-Ying Zhu jun-Duo Li Xi-Ping Xue Chen Li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The new Wuqing 70 m radio telescope is first used for the downlink data reception in the first Mars exploration mission of China,and will be used for the other deep space communications and radio astronomical observations in the *** main specifications and measurement results of some properties in the X-band are introduced in this paper,such as pointing calibration,gain and efficiency,system noise temperature,system equivalent flux density,and variations with *** 23 parameters pointing calibration model considering the atmospheric refraction correction in real time is presented in the telescope,and the pointing accuracy reaches 570 in azimuth direction and 607 in elevation direction for different weather *** than 62%efficiencies are achieved at full elevation range,and more than 70%in the *** system equivalent flux density of the X-band in the mid-elevation reaches 26 Jy.

关键词： telescopes astronomical instrumentation methods and techniques atmospheric effects

Recent advances in vacancy engineering for reliable lithiumsulfur batteries

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Rare Metals 2024年第2期43卷 455-477页

作者： Wen-Dong liu Xiao Tang jun-An Feng Chao-Yue Zhang Hao liu Chuan Shi Xiao-Xian Zhao jian-jun Song College of Physics School of Chemistry and Chemical EngineeringQingdao UniversityQingdao266071China Faculty of Science Centre for Clean Energy TechnologySchool of Mathematical and Physical SciencesUniversity of Technology SydneySydneyNSW2007Australia Department of Chemistry College of ScienceHebei Agricultural UniversityBaoding071001China

The high-energy-density and low-cost features endow lithium-sulfur batteries with broad application ***,many drawbacks,especially the detrimental shuttle effect,have hindered the further development of *** response,a lot of new structures have been applied to suppress the shuttle effect and promote the development of ***,vacancy engineering has gained the attention of researchers due to its unique electronic *** review aims to analyze the application of vacancy engineering in ***,the electrochemistry of LSBs has been systematically discussed and the existing challenges as well as improvement tactics of LSBs have also been ***,the preparation methods and characterization technologies of various vacancies are summarized,including oxygen vacancies,sulfur vacancies,selenium vacancies,other anion vacancies,cation vacancies,*** latest applications of vacancy engineering in LSBs are also summarized in this ***,some prospects and insights for further investigation and practical application of vacancy engineering in LSBs are put forward.

关键词： Lithium-sulfur batteries(LSBs) Defects Vacancy engineering Electronic structure Shuttle effect

Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao jian Zheng Jin Guo Yunbo Shi Hengzhen Feng jun Tang jun liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

Preparation and Rheological Characterization of Long Chain Branching Polyglycolide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin liu Ming-Fu Lyu Heng-Yuan Zhang jian-Ye liu Shi-jun Zhang Beijing University of Chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.

关键词： Polyglycolide(PGA) Long chain branching(LCB) Rheology

Influences of Inflow Condition on Non-Axisymmetric Flows in Turbine Exhaust Hoods

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Journal of Thermal Science 2008年第4期17卷 305-313页

作者： Jing-Lun FU jian-jun liu Institute of Engineering ThermophysicsChinese Academy of Sciences Beijing 100190 China

在一台蒸气汽轮机的复杂 3D 流动与不同入口用尽兜帽模型打漩并且入口总数压力光线的分布被采用 CFX-5 模仿了并且在这分析了纸。它发现了在中心的正切的流动角度有的入口 exhaust 兜帽表演上的否定效果，当时光线的分发有的入口总数压... 详细信息

在一台蒸气汽轮机的复杂 3D 流动与不同入口用尽兜帽模型打漩并且入口总数压力光线的分布被采用 CFX-5 模仿了并且在这分析了纸。它发现了在中心的正切的流动角度有的入口 exhaust 兜帽表演上的否定效果，当时光线的分发有的入口总数压力的一个否定坡度兜帽表演上的积极影响。它数字地也证实了在兜帽入口罐头的全部的压力的合适的分布成功地消除由不恰当的入口引起的否定效果打漩分发并且改进兜帽空气动力学的性能。

关键词：涡轮电磁感应轴对称流入物