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Reconstructing the landing trajectory of the CE-3 lunar probe by using images from the landing camera

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Research in Astronomy and Astrophysics 2014年第12期14卷 1530-1542页

作者： jian-jun liu Wei Yan Chun-Lai Li Xu Tan Xin Ren Ling-Li Mu Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences

An accurate determination of the landing trajectory of Chang＇e-3 （CE-3） is significant for verifying orbital control strategy, optimizing orbital planning, accu- rately determining the landing site of CE-3 and analyzing the geological background of the landing site. Due to complexities involved in the landing process, there are some differences between the planned trajectory and the actual trajectory of CE-3. The land- ing camera on CE-3 recorded a sequence of the landing process with a frequency of 10 frames per second. These images recorded by the landing camera and high-resolution images of the lunar surface are utilized to calculate the position of the probe, so as to reconstruct its precise trajectory. This paper proposes using the method of trajectory reconstruction by Single Image Space Resection to make a detailed study of the hov- ering stage at a height of 100 m above the lunar surface. Analysis of the data shows that the closer CE-3 came to the lunar surface, the higher the spatial resolution of im- ages that were acquired became, and the more accurately the horizontal and vertical position of CE-3 could be determined. The horizontal and vertical accuracies were 7.09 m and 4.27 m respectively during the hovering stage at a height of 100.02 m. The reconstructed trajectory can reflect the change in CE-3＇s position during the powered descent process. A slight movement in CE-3 during the hovering stage is also clearly demonstrated. These results will provide a basis for analysis of orbit control strategy, and it will be conducive to adjustment and optimization of orbit control strategy in follow-up missions.

关键词： Moon - methods: data analysis - techniques: image processing

Structural and electrical properties of carbon-ion-implanted ultrananocrystalline diamond films

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Chinese Physics B 2018年第9期27卷 426-433页

作者： Hui Xu jian-jun liu Hai-Tao Ye D J Coathup A V Khomich Xiao-jun Hu College of Materials Science and Engineering Zhejiang University of Technology Hangzhou 310014 China Aston Institute of Materials Research School of Engineering and Applied Science Aston University Birmingham B4 7ET United Kingdom V. A. Kotelnikov Institute of Radio-Engineering and Electronics Russian Academy of Sciences Moscow 14l 190 Russia National Research Nuclear University MEPhI Moscow Russia

We investigate the structural and electrical properties of carbon-ion-implanted ultrananocrystalline diamond（UNCD）films. Impedance spectroscopy measurements show that the impedance of diamond grains is relatively stable, while that of grain boundaries（GBs）（Rb） significantly increases after the C~＋ implantation, and decreases with the increase in the annealing temperature（Ta） from 650℃ to 1000℃. This implies that the C~＋ implantation has a more significant impact on the conductivity of GBs. Conductive atomic force microscopy demonstrates that the number of conductive sites increases in GB regions at Ta above 900℃, owing to the formation of a nanographitic phase confirmed by high-resolution transmission electronic microscopy. Visible-light Raman spectra show that resistive trans-polyacetylene oligomers desorb from GBs at Ta above 900℃, which leads to lower Rb of samples annealed at 900 and 1000℃. With the increase in Ta to 1000℃, diamond grains become smaller with longer GBs modified by a more ordered nanographitic phase, supplying more conductive sites and leading to a lower Rb.

关键词： ultrananocrystalline diamond C-ion implantation annealing electrical properties

6-gingerol protects nucleus pulposus-derived mesenchymal stem cells from oxidative injury by activating autophagy

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World Journal of Stem Cells 2020年第12期12卷 1603-1622页

作者： Li-Ping Nan Feng Wang Yang liu Zhong Wu Xin-Min Feng jun-jian liu Liang Zhang Department of Orthopedic Tongji University School of MedicineShanghai Tenth People’s HospitalTenth People’s Hospital of Tongji UniversityShanghai 200072China Department of Spine Surgery Tongji University School of MedicineShanghai East HospitalShanghai 200120China Department of Orthopedic West China Hospital of Sichuan UniversityChengdu 610000Sichuan ProvinceChina Department of Orthopedics Shanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200072China Department of Orthopedics Clinical Medical College of Yangzhou UniversityYangzhou 225000Jiangsu ProvinceChina

BACKGROUND To date,there has been no effective treatment for intervertebral disc degeneration(IDD).Nucleus pulposus-derived mesenchymal stem cells(NPMSCs)showed encouraging results in IDD treatment,but the overexpression of reactive oxygen species(ROS)impaired the endogenous repair abilities of NPMSCs.6-gingerol(6-GIN)is an antioxidant and anti-inflammatory reagent that might protect NPMSCs from *** To investigate the effect of 6-GIN on NPMSCs under oxidative conditions and the potential *** The cholecystokinin-8 assay was used to evaluate the cytotoxicity of hydrogen peroxide and the protective effects of *** levels were measured by 2´7´-dichlorofluorescin diacetate *** metalloproteinase(MMP)was detected by the tetraethylbenzimidazolylcarbocyanine iodide *** assay and Annexin V/PI double-staining were used to determine the apoptosis ***,autophagy-related proteins(Beclin-1,LC-3,and p62),apoptosisassociated proteins(Bcl-2,Bax,and caspase-3),and PI3K/Akt signaling pathwayrelated proteins(PI3K and Akt)were evaluated by Western blot *** were detected by transmission electron microscopy in ***-3 was also detected by *** mRNA expression of collagen II and aggrecan was evaluated by real-time polymerase chain reaction(RT-PCR),and the changes in collagen II and MMP-13 expression were verified through an immunofluorescence *** 6-GIN exhibited protective effects against hydrogen peroxide-induced injury in NPMSCs,decreased hydrogen peroxide-induced intracellular ROS levels,and inhibited cell apoptosis.6-GIN could increase Bcl-2 expression and decrease Bax and caspase-3 *** MMP,Annexin V-FITC/PI flow cytometry and TUNEL assay results further confirmed that 6-GIN treatment significantly inhibited NPMSC apoptosis induced by hydrogen peroxide.6-GIN treatment promoted extracellular matrix(ECM)expression by reducing the oxidative stress injury-induced increas

关键词： Nucleus pulposus-derived mesenchymal stem cells 6-Gingerol Intervertebral disc degeneration Oxidative stress Autophagy Apoptosis

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

Effect of electroacupuncture at Sibai on the gastric myoelectric acitivities of denervated rats

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World Journal of Gastroenterology 2006年第36期12卷 5897-5901页

作者： Xiao-Rong Chang Jie Yan Yan-Ling Zhao jiang-Shang Li jian-Hua liu jun-Feng He College of Acupuncture and Massage Hunan University of Traditional Chinese Medicine Changsha 410007 Hunan Province China

AIM： To explore the mechanism of the exciting effects of electro-acupuncture （EA） at Sibai on the gastric myoelectric activities. METHODS： A total of 32 rats were randomly divided into four groups. Through intraperitoneal injection with atropine （the anti-cholinergic agent by blockade of muscarinic receptors）, hexarnethonium （automatic nerve ganglion-blocking agent） and reserpine （anti-adrenergic agent by depleting the adrenergic nerve terminal of its norepinephrine store）, effects of EA at Sibai on the gastric myoelectric activities of the denervated rats were observed. RESULTS： After intraperitoneal injection of atropine and hexamethonium, the average amplitude and ratio of period to time in the phase of high activity of gastric myoelectric slow wave, and the average numbers of the peaks of gastric myoelectric fast wave were significantly decreased （P 〈 0.01, P 〈 0.05, P 〈 0.01）, while after intraperitoneal injection of reserpine, the aforementioned three parameters were increased （P 〈 0.01, P 〈 0.05, P 〈 0.01）. EA at Sibai point partially relieved the inhibitory effect of atropine and hexamethonium on the gastric myoelectric activities in the rats （P 〈 0.05 or P 〉 0.05）. CONCLUSION： Cholinergic and adrenergic nervous systems and autonomic nerve ganglion participate in the peripheral passage of the controlling effects of EA at Foot Yangming Channel on gastrointestinal tract.

关键词： Electro-acupuncture Rats Sibai Nerve block Gastric myoelectric activities

Scientific data products and the data pre-processing subsystem of the Chang'e-3 mission

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Research in Astronomy and Astrophysics 2014年第12期14卷 1682-1694页

作者： Xu Tan jian-jun liu Chun-Lai Li jian-Qing Feng Xin Ren Fen-Fei Wang Wei Yan Wei Zuo Xiao-Qian Wang Zhou-Bin Zhang Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences

The Chang＇e-3 （CE-3） mission is China＇s first exploration mission on the surface of the Moon that uses a lander and a rover. Eight instruments that form the scientific payloads have the following objectives：（1） investigate the morphological features and geological structures at the landing site; （2） integrated in-situ analysis of minerals and chemical compositions; （3） integrated exploration of the structure of the lunar interior; （4） exploration of the lunar-terrestrial space environment, lunar sur- face environment and acquire Moon-based ultraviolet astronomical observations. The Ground Research and Application System （GRAS） is in charge of data acquisition and pre-processing, management of the payload in orbit, and managing the data products and their applications. The Data Pre-processing Subsystem （DPS） is a part of GRAS. The task of DPS is the pre-processing of raw data from the eight instruments that are part of CE-3, including channel processing, unpacking, package sorting, calibration and correction, identification of geographical location, calculation of probe azimuth angle, probe zenith angle, solar azimuth angle, and solar zenith angle and so on, and conducting quality checks. These processes produce Level 0, Level 1 and Level 2 data. The computing platform of this subsystem is comprised of a high-performance computing cluster, including a real-time subsystem used for processing Level 0 data and a post-time subsystem for generating Level 1 and Level 2 data. This paper de- scribes the CE-3 data pre-processing method, the data pre-processing subsystem, data classification, data validity and data products that are used for scientific studies.

关键词： Moon: data products -- methods: data pre-processing -- space vehicles:instruments

Leading Edge Film Cooling Enhancement for an Inlet Guide Vane with Fan-Shaped Holes

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Journal of Thermal Science 2010年第6期19卷 514-518页

作者： jian-jun liu, Bai-Tao AN, Jie liu and Zhan W Institute of Engineering Thermophysics, Chinese Academy of Sciences, P. O. Box 2706, Beijing 100190, China Professor,PhD Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

This paper describes the improvement of leading edge film cooling effectiveness for a turbine inlet guide vane by using fan-shaped film cooling holes. The modification details are presented in comparison with the base-line configuration of cylindrical holes. Numerical simulations were carried out for the base-line and modified configurations by using CFX, in which the k-ε turbulence model and scalable wall function were chosen. Contours of adiabatic film cooling effectiveness on the blade surfaces and span-wise distributions of film cooling effectiveness downstream the rows of cooling holes interested for the different cooling configurations were compared and discussed. It is showed that with the use of fan-shaped cooling holes around the leading edge, the adiabatic film cooling effectiveness can be enhanced considerably. In comparison with the cylindrical film cooling holes, up to 40% coolant mass flow can be saved by using fan-shaped cooling holes to obtain the comparable film cooling effectiveness for the studied inlet guide vane.

关键词： Inlet Guide Vane Film Cooling Effectiveness Fan-Shaped Hole Leading Edge

Data processing and preliminary results of the Chang'e-3 VIS/NIR Imaging Spectrometer in-situ analysis

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Research in Astronomy and Astrophysics 2014年第12期14卷 1578-1594页

作者： Bin liu Chun-Lai Li Guang-Liang Zhang Rui Xu jian-jun liu Xin Ren Xu Tan Xiao-Xia Zhang Wei Zuo Wei-Bin Wen Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Space Active Opto-Electronics Technology Shanghai Institute of TechnicalPhysics Chinese Academy of Sciences

The Chang＇e-3 Visible and Near-infrared Imaging Spectrometer （VNIS） is one of the four payloads on the Yutu rover. After traversing the landing site during the first two lunar days, four different areas are detected, and Level 2A and 2B ra- diance data have been released to the scientific community. The released data have been processed by dark current subtraction, correction for the effect of temperature, radiometric calibration and geometric calibration. We emphasize approaches for re- flectance analysis and mineral identification for in-situ analysis with VNIS. Then the preliminary spectral and mineralogical results from the landing site are derived. After comparing spectral data from VNIS with data collected by the Ma instrument and samples of mare that were returned from the Apollo program, all the reflectance data have been found to have similar absorption features near 1000 nm except lunar sample 71061. In addition, there is also a weak absorption feature between 1750-2400nm on VNIS, but the slopes of VNIS and Ma reflectance at longer wavelengths are lower than data taken from samples of lunar mare. Spectral parameters such as Band Centers and Integrated Band Depth Ratios are used to analyze mineralogical features. The results show that detection points E and N205 are mixtures of high-Ca pyroxene and olivine, and the composition of olivineat point N205 is higher than that at point E, but the compositions of detection points S3 and N203 are mainly olivine-rich. Since there are no obvious absorption features near 1250 nm, plagioclase is not directly identified at the landing site.

关键词： Chang'e-3 -- VNIS -- in-situ analysis -- data processing