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Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil
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作者 Chen Li Wenhui Ma +1 位作者 Yang Li Kuixian Wei 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1241-1248,共8页
Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical engineering.It involves systematic and theoretical engineering technology for utilizing planetary resources in sit... Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical engineering.It involves systematic and theoretical engineering technology for utilizing planetary resources in situ.However,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the Earth.In this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil samples.The microstructural characteristics of the lunar soil may drastically change its metallurgical performance.The main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral crystals.The nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar soil.Hydrogen ions injected by solar wind may promote the hydrogen reduction process.The widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar soil.Therefore,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar soil.This is a property that earth samples and tradi-tional simulated lunar soil lack.The application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil. 展开更多
关键词 space metallurgy change-5 lunar soil space weathering metallurgical performance
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miR-30e-5p通过靶向PIK3CD介导PI3K/AKT/mTOR信号通路对肝癌细胞侵袭和迁移的影响
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作者 郝云鹤 邹瑞 +1 位作者 赵晓彪 李铎 《中国现代普通外科进展》 CAS 2024年第1期19-24,共6页
目的:探讨mi R-30e-5p通过靶向磷酸肌醇-3-激酶催化亚基δ肽(PIK3CD)介导磷酸肌醇3激酶(PI3K)/蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路抑制肝癌细胞的侵袭、迁移的机制。方法:将Hep G2通过转染相应质粒后分为对照组、miR-... 目的:探讨mi R-30e-5p通过靶向磷酸肌醇-3-激酶催化亚基δ肽(PIK3CD)介导磷酸肌醇3激酶(PI3K)/蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路抑制肝癌细胞的侵袭、迁移的机制。方法:将Hep G2通过转染相应质粒后分为对照组、miR-30e-5p mimics组、PIK3CD敲低组、阴性对照组、miR-30e-5p mimics+PIK3CD过表达组,实时荧光定量PCR和免疫印迹检测细胞miR-30e-5p、PIK3CD与PI3K/AKT/mTOR信号通路表达;CCK-8法检测各组细胞增殖率;细胞划痕实验和Transwell侵袭实验分别检测各组细胞迁移、侵袭情况;以免疫印迹实验检测各组细胞基质金属蛋白酶(MMP)2、MMP9及E-cadherin、N-cadherin、Vimentin蛋白表达。采用双荧光素酶报告实验检测miR-30e-5p对PIK3CD的靶向调节。结果:与对照组相比,mi R-30e-5p mimics组、PIK3CD敲低组增殖率、迁移率、侵袭数、PIK3CD蛋白与mRNA表达、N-cadherin、MMP2、MMP9、磷酸化PI3K、磷酸化AKT、磷酸化m TOR蛋白表达降低(P<0.05),E-cadherin表达升高(P<0.05)。过表达PIK3CD减弱了miR-30e-5p mimics对肝癌细胞增殖、迁移、侵袭的抑制作用,并升高PI3K/AKT/mTOR通过相关蛋白表达。miR-30e-5p可靶向下调PIK3CD表达。结论:上调miR-30e-5p可通过降低PIK3CD表达而阻止PI3K/AKT/mTOR信号激活,从而抑制肝癌细胞增殖、迁移和侵袭。 展开更多
关键词 miR-30e-5p PIK3CD PI3K/AKT/MTOR 肝肿瘤 侵袭 迁移
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Lunar Penetrating Radar onboard the Chang'e-3 mission 被引量:12
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作者 Guang-You Fang Bin Zhou +11 位作者 Yi-Cai Ji Qun-Ying Zhang Shao-Xiang Shen Yu-Xi Li Hong-Fei Guan Chuan-Jun Tang Yun-Ze Gao Wei Lu Sheng-Bo Ye Hai-Dong Han Jin Zheng Shu-Zhi Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1607-1622,共16页
Lunar Penetrating Radar (LPR) is one of the important scientific instru- ments onboard the Chang'e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structure... Lunar Penetrating Radar (LPR) is one of the important scientific instru- ments onboard the Chang'e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structures. This paper describes the goals of the mission, as well as the basic principles, design, composition and achievements of the LPR. Finally, experiments on a glacier and the lunar surface are analyzed. 展开更多
关键词 change-3 mission -- moon rover -- Lunar Penetrating Radar
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Development and calibration of the Moon-based EUV camera for Chang'e-3 被引量:4
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作者 Bo Chen Ke-Fei Song +31 位作者 Zhao-Hui Li Qing-Wen Wu Qi-Liang Ni Xiao-Dong Wang Jin-Jiang Xie Shi-Jie Liu Ling-Ping He Fei He Xiao-Guang Wang Bin Chen Hong-Ji Zhang Xiao-Dong Wang Hai-Feng Wang Xin Zheng Shu-Lin E Yong-Cheng Wang Tao Yu Liang Sun Jin-Ling Wang Zhi Wang Liang Yang Qing-Long Hu Ke Qiao Zhong-Su Wang Xian-Wei Yang Hai-Ming Bao Wen-Guang Liu Zhe Li Ya Chen Yang Gao Hui Sun Wen-Chang Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1654-1663,共10页
The process of development and calibration for the first Moon-based ex- treme ultraviolet (EUV) camera to observe Earth's plasmasphere is introduced and the design, test and calibration results are presented. The E... The process of development and calibration for the first Moon-based ex- treme ultraviolet (EUV) camera to observe Earth's plasmasphere is introduced and the design, test and calibration results are presented. The EUV camera is composed of a multilayer film mirror, a thin film filter, a photon-counting imaging detector, a mech- anism that can adjust the direction in two dimensions, a protective cover, an electronic unit and a thermal control unit. The center wavelength of the EUV camera is 30.2 nm with a bandwidth of 4.6nm. The field of view is 14.7° with an angular resolution of 0.08°, and the sensitivity of the camera is 0.11 count s-1 Rayleigh-1. The geomet- ric calibration, the absolute photometric calibration and the relative photometric cal- ibration are carried out under different temperatures before launch to obtain a matrix that can correct geometric distortion and a matrix for relative photometric correction, which are used for in-orbit correction of the images to ensure their accuracy. 展开更多
关键词 change-3 -- EUV camera: development: calibration -- Earth's plas-masphere -- lunar exploration
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Data processing and preliminary results of the Chang'e-3 VIS/NIR Imaging Spectrometer in-situ analysis 被引量:3
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作者 Bin Liu Chun-Lai Li +7 位作者 Guang-Liang Zhang Rui Xu Jian-Jun Liu Xin Ren Xu Tan Xiao-Xia Zhang Wei Zuo Wei-Bin Wen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1578-1594,共17页
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 detecte... 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. 展开更多
关键词 change-3 -- VNIS -- in-situ analysis -- data processing
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黄芩素对人乳腺癌细胞系MDA-MB-231侵袭、迁移、上皮间充质转化的调控作用及其机制
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作者 陈林 梁秋果 +1 位作者 吉杨丹 王恒 《山东医药》 CAS 2024年第6期10-13,共4页
目的观察黄岑素对人乳腺癌细胞系MDA-MB-231的侵袭、迁移及上皮间充质转化(EMT)的调控作用,探讨其可能作用机制。方法取对数生长期MDA-MB-231细胞分为一组、二组、三组及对照组,一组、二组、三组分别加入2.5、5、10μmol/L的黄岑素,对... 目的观察黄岑素对人乳腺癌细胞系MDA-MB-231的侵袭、迁移及上皮间充质转化(EMT)的调控作用,探讨其可能作用机制。方法取对数生长期MDA-MB-231细胞分为一组、二组、三组及对照组,一组、二组、三组分别加入2.5、5、10μmol/L的黄岑素,对照组不做任何处理。培养48 h时采用划痕修复实验观察四组细胞迁移能力、采用Transwell侵袭实验观察四组细胞侵袭能力,采用Western Blotting法检测细胞EMT标志物波形蛋白(vimentin)及E-钙黏蛋白(E-cadherin)、整合素αv、β3、磷酸化黏着斑激酶(p-FAK)、磷酸化磷脂酰肌醇3激酶(整合素p-PI3K)。结果与对照组相比,黄岑素组细胞迁移率降低、侵袭细胞数少,细胞E-cadherin相对表达量高,vimentin、整合素αv、整合素β3、p-FAK、p-PI3K蛋白相对表达量低,且呈剂量依赖性(P均<0.05)。结论黄芩素抑制MDA-MB-231细胞的侵袭、迁移及EMT。黄岑素可能通过抑制整合素αv、整合素β3表达,进一步抑制p-FAK、p-PI3K蛋白表达,抑制MDA-MB-231的侵袭、迁移及EMT。 展开更多
关键词 黄芩素 乳腺癌 细胞侵袭 细胞迁移 上皮间质转化 波形蛋白 e-钙黏蛋白 整合素αv、整合素β3 黏着斑激酶 磷脂酰肌醇3激酶
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Preface: The Chang'e-3 lander and rover mission to the Moon 被引量:1
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作者 Wing-Huen Ip Jun Yan +1 位作者 Chun-Lai Li Zi-Yuan Ouyang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1511-1513,共3页
The Chang'e-3 (CE-3) lander and rover mission to the Moon was an in- termediate step in China's lunar exploration program, which will be followed by a sample return mission. The lander was equipped with a number o... The Chang'e-3 (CE-3) lander and rover mission to the Moon was an in- termediate step in China's lunar exploration program, which will be followed by a sample return mission. The lander was equipped with a number of remote-sensing instruments including a pair of cameras (Landing Camera and Terrain Camera) for recording the landing process and surveying terrain, an extreme ultraviolet camera for monitoring activities in the Earth's plasmasphere, and a first-ever Moon-based ultravi- olet telescope for astronomical observations. The Yutu rover successfully carried out close-up observations with the Panoramic Camera, mineralogical investigations with the VIS-NIR Imaging Spectrometer, study of elemental abundances with the Active Particle-induced X-ray Spectrometer, and pioneering measurements of the lunar sub- surface with Lunar Penetrating Radar. This special issue provides a collection of key information on the instrumental designs, calibration methods and data processing pro- cedures used by these experiments with a perspective of facilitating further analyses of scientific data from CE-3 in preparation for future missions. 展开更多
关键词 change-3 - Moon lander - rover - radar - lunar telescope
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Correlations between plasmapause evolutions and auroral signatures during substorms observed by Chang'e-3 EUV Camera 被引量:2
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作者 XiaoXin Zhang Fei He +2 位作者 Bo Chen Chao Shen HuaNing Wang 《Earth and Planetary Physics》 2017年第1期35-43,共9页
The plasmapause locations determined from the Chang'e-3(CE-3) Extreme Ultraviolet Camera(EUVC) images and the auroral boundaries determined from the Defense Meteorological Satellite Program(DMSP) Special Sensor Ul... The plasmapause locations determined from the Chang'e-3(CE-3) Extreme Ultraviolet Camera(EUVC) images and the auroral boundaries determined from the Defense Meteorological Satellite Program(DMSP) Special Sensor Ultraviolet Spectrographic Imager(SSUSI) images are used to investigate the plasmaspheric evolutions during substorms. The most important finding is a nightside pointing plasmaspheric plume observed at 23:05 UT on 21 April 2014 under quiet solar wind and geomagnetic conditions, which drifted from the dusk sector. High correlations between the plasmapause evolutions and the auroral signatures exist during substorms. After substorm onset, the plasmapause erosion and the equatorward expansion of the auroral oval occur almost simultaneously in both MLT and UT, and then both the erosion and the expansion propagate westward and eastward. It is suggested that the plasmaspheric erosion and its MLT propagations are induced by the enhanced earthward plasma convection during substorm period, and the substorm dipolarization causes pitch-angle scattering of plasma sheet electrons and the resulting precipitation excites aurora emissions at the same time. 展开更多
关键词 PLASMASPHERE change-3 EUVC minimum L Algorithm SUBSTORM
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Deployment Reliability Test and Assessment for Landing Gear of Chang' E-3 Probe 被引量:1
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作者 吴琼 杨建中 +2 位作者 傅惠民 徐青华 满剑锋 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期782-784,800,共4页
Chang'E-3 probe incorporates four landing gears to assure the soft-landing,which are stowed while launching and deployed after separated from rocket. Deployment reliability is quite crucial for this mission. The d... Chang'E-3 probe incorporates four landing gears to assure the soft-landing,which are stowed while launching and deployed after separated from rocket. Deployment reliability is quite crucial for this mission. The deployment reliability test( DRT) method and assessment method were developed in this paper. Then DRT was conducted and the deployment reliability estimate of Chang'E-3probe was used to verify the proposed methods. 展开更多
关键词 change-3 landing gear DEPLOYMENT RELIABILITY test ASSESSMENT
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自然杀伤细胞来源外泌体的miR-30e-3p抑制人食管鳞状细胞癌细胞增殖和侵袭
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作者 孙明月 李洪霖 冯保荣 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2023年第4期295-302,共8页
目的 研究自然杀伤(NK)细胞来源外泌体的miR-30e-3p对食管鳞状细胞癌(ESCC)细胞增殖、凋亡和侵袭的影响。方法 从健康供体的外周血中分离和扩增NK细胞,并分离NK细胞外泌体(EXO)进行鉴定。NK细胞外泌体与NEC细胞进行共培养,随机分为Exo1... 目的 研究自然杀伤(NK)细胞来源外泌体的miR-30e-3p对食管鳞状细胞癌(ESCC)细胞增殖、凋亡和侵袭的影响。方法 从健康供体的外周血中分离和扩增NK细胞,并分离NK细胞外泌体(EXO)进行鉴定。NK细胞外泌体与NEC细胞进行共培养,随机分为Exo1和Exo2组。采用透射电子显微镜观察外泌体形态及大小。Western blot法检测外泌体凋亡相关基因2相互作用蛋白X(ALIX)、抗肿瘤易感基因101(TSG101)、 CD81、钙联蛋白(calnexin)表达。将miR-30e-3p模拟物(miR-30e-3p mimic)、 miR-30e-3p抑制物(miR-30e-3p inhibitor)及阴性对照(miR-NC)转入NK细胞,并分离相应的外泌体与NEC细胞进行共培养。CCK-8法检测细胞增殖,流式细胞术检测细胞周期,异硫氰酸荧光素标记的膜联素Ⅴ/碘化丙啶双染法检测细胞凋亡,Transwell^(TM)侵袭实验检测细胞侵袭能力。实时定量PCR检测NCE细胞和外泌体中miR-23b、 miR-422a、 miR-133b、 miR-124、 miR-30e-3p和miR-99a的表达。结果 NK细胞中CD56+CD3+细胞比例为(0.071±0.008)%,CD56+CD16+细胞比例为(90.6±10.6)%。从NK细胞分离的外泌体直径为30~150 nm,且表达ALIX、 TSG101、 CD81,不表达calnexin。NK细胞来源外泌体抑制NEC细胞增殖和侵袭、增加细胞凋亡,降低S期细胞比例并增加G1期细胞比例。过表达miR-30e-3p的NK细胞来源外泌体抑制NEC细胞增殖和侵袭,并阻滞细胞周期和促进细胞凋亡,敲低miR-30e-3p的NK细胞来源外泌体则相反。结论NK细胞来源外泌体miR-30e-3p阻断人ESCC细胞的细胞周期,抑制其增殖和侵袭并诱导其凋亡。 展开更多
关键词 食管鳞状细胞癌 自然杀伤(NK)细胞 外泌体 miR-30e-3p
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Visualization of Landscape Changes in a 3D Environment Using the Storytelling Approach—The Example of the City of Pristina
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作者 Festina Sadiku 《Journal of Geographic Information System》 2023年第5期482-514,共33页
This study proposes a detailed concept of how landscape changes can be transferred and communicated in a 3D environment using the storytelling approach. In 2018, Mocnik and Fairbairn argued that maps are good for repr... This study proposes a detailed concept of how landscape changes can be transferred and communicated in a 3D environment using the storytelling approach. In 2018, Mocnik and Fairbairn argued that maps are good for representing a geographic space but texts have a better benefit than maps for telling a story [1]. A framework is presented on how a landscape change can be retrieved out of textual descriptions. A prototype of a 3D model with a projection on top of it was developed. The case study tells the story of the landscape change in the city of Pristina. The key element of the visualization is a timeline. Several media like cadastral maps, orthophotos, texts, graphics, and background sound are used and combined in an animated light show and the visualization was evaluated within a user study. 展开更多
关键词 Landscape change VISUALIZATION STORYTELLING 3D Models Pristina
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基于机器学习的汾渭平原PM_(2.5)和O_(3)变化特征及影响因素
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作者 李焕 苏慧 +2 位作者 张婷 赵竹子 王璐瑶 《环境化学》 CAS CSCD 北大核心 2024年第5期1585-1598,共14页
本文以2017—2021年汾渭平原典型城市西安大气PM_(2.5)和O_(3)浓度数据为基础,运用机器学习方法分析了PM_(2.5)和O_(3)的变化特征和趋势,讨论了污染气体(NO_(2)、SO_(2)、CO和HCHO)与气象因素(温度、相对湿度、风速、大气压力、边界层... 本文以2017—2021年汾渭平原典型城市西安大气PM_(2.5)和O_(3)浓度数据为基础,运用机器学习方法分析了PM_(2.5)和O_(3)的变化特征和趋势,讨论了污染气体(NO_(2)、SO_(2)、CO和HCHO)与气象因素(温度、相对湿度、风速、大气压力、边界层高度和太阳辐射)对PM_(2.5)和O_(3)浓度变化的交互影响.Theil-Sen趋势分析发现2017—2021年西安市PM_(2.5)和O_(3)分别以每年6.03%和2.06%的速度下降.单因素广义加性模型(GAM)中,NO_(2)、SO_(2)和CO对PM_(2.5)浓度变化影响的模型解释率较高,温度、太阳辐射和大气压对O_(3)浓度变化影响的模型解释率较高.多因素GAM模型中,PM_(2.5)和O_(3)均呈现非线性变化,模型的解释方差分别为84.9%和75.0%,拟合程度较高.通过等高线图分析了多个气象因素和多种污染气体两两交互作用分别对PM_(2.5)和O_(3)浓度的影响,其中温度和污染气体(NO_(2)、SO_(2)、CO和O_(3))对PM_(2.5)浓度的影响更大;温度和太阳辐射对O_(3)的影响更大.NO_(2)和CO分别与气象条件两两相互作用时,PM_(2.5)浓度随NO_(2)和CO的增高而增高,O_(3)浓度则与NO_(2)和CO的变化趋势相反.结合本地污染物源清单,建议加强控制工业源和移动源排放,有助于降低PM_(2.5)和O_(3)的浓度. 展开更多
关键词 PM2.5 O_(3) 机器学习 变化趋势 影响因素
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Organic matter transformation ratio, hydrocarbon expulsion efficiency and shale oil enrichment type in Chang 7_(3) shale of Upper Triassic Yanchang Formation in Ordos Basin, NW China
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作者 ZHAO Wenzhi BIAN Congsheng +4 位作者 LI Yongxin LIU Wei DONG Jin WANG Kun ZENG Xu 《Petroleum Exploration and Development》 2023年第1期14-26,共13页
The major enrichment type of shale oil in the Chang 7_(3) shale of Upper Triassic Yanchang Formation in the Ordos Basin is unknown.This paper analyzes the organic matter transformation ratio,hydrocarbon expulsion effi... The major enrichment type of shale oil in the Chang 7_(3) shale of Upper Triassic Yanchang Formation in the Ordos Basin is unknown.This paper analyzes the organic matter transformation ratio,hydrocarbon expulsion efficiency and roof/floor sealing conditions of the Chang 7_(3) shale,and evaluates the major enrichment type of shale oil in this interval.The average organic matter transformation ratio of the Chang 7_(3) shale is about 45%;in other words,more than 50%of the organic matters have not transformed to hydrocarbons,and the lower the maturity,the greater the proportion of untransformed organic matters.The cumulative hydrocarbon expulsion efficiency of the transformed hydrocarbon is 27.5% on average,and the total proportion of untransformed organic matters plus retained hydrocarbons is greater than 70%.The relative hydrocarbon expulsion efficiency of the Chang 7_(3) shale is 60%on average,that is,about 40% of hydrocarbons retain in the shale.The Chang 7_(3) shale corresponds to Chang 7_(1+2) and Chang 8 sandstones as the roof and floor,respectively,and is further overlaid by Chang 6 shale,where extensive low porosity and low permeability–tight oil reservoirs have formed in the parts with relatively good porosity and permeability.Moreover,the Chang 7_(3) shale is tested to be in a negative pressure system(the pressure coefficient of 0.80–0.85).Therefore,the roof/floor sealing conditions of the Chang 7_(3) shale are poor.The retained hydrocarbons appear mostly in absorbed status,with low mobility.It is concluded that the medium–high mature shale oil is not the major enrichment type of shale oil in the Chang 7_(3) shale,but there may be enrichment opportunity for shale oil with good mobility in the areas where the sealing conditions are good without faults and fractures and oil reservoirs are formed off Chang 7_(1+2),Chang 6 and Chang 8.Furthermore,low–medium mature shale oil is believed to have great potential and is the major enrichment type of shale oil in the Chang 7_(3) shale.It is recommended to prepare relevant in-situ conversion technologies by pilot test and figure out the resource availability and distribution. 展开更多
关键词 organic matter transformation ratio hydrocarbon expulsion efficiency sealing condition continental shale oil major enrichment type chang 7_(3)shale Triassic Ordos Basin
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Reliability Design for the Landing Gear of Chang'E-3 Probe
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作者 杨建中 吴琼 +1 位作者 满剑锋 朱汪 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期1006-1010,共5页
Landing gear is one of the important components of Chang'E-3 Probe.The device was used to absorb the impact energy of Chang'E-3 Probe during the landing process.After landing on the moon,it can support the lan... Landing gear is one of the important components of Chang'E-3 Probe.The device was used to absorb the impact energy of Chang'E-3 Probe during the landing process.After landing on the moon,it can support the lander steadily for a long time.In order to assure the reliability of the landing gear and deal with the extremely severe landing conditions,many reliability measures were adopted in the design procedure,such as selection of cushion materials,optimization of mechanism configuration,design of deployment mode,allocation of buffer force and control of its variation.The successful landing on the moon of Chang'E-3 Probe has completely verified the high reliability of the landing gear. 展开更多
关键词 landing gear change-3 Probe RELIABILITY design material CONFIGURATION
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Comprehensive study of the ultrafast photoexcited carrier dynamics in Sb_(2)Te_(3)–GeTe superlattices
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作者 叶之江 金钻明 +7 位作者 蒋叶昕 卢琦 贾梦辉 钱冬 黄夏敏 李舟 彭滟 朱亦鸣 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期381-387,共7页
Chalcogenide superlattices Sb_(2)Te_(3)-GeTe is a candidate for interfacial phase-change memory(iPCM) data storage devices.By employing terahertz emission spectroscopy and the transient reflectance spectroscopy togeth... Chalcogenide superlattices Sb_(2)Te_(3)-GeTe is a candidate for interfacial phase-change memory(iPCM) data storage devices.By employing terahertz emission spectroscopy and the transient reflectance spectroscopy together,we investigate the ultrafast photoexcited carrier dynamics and current transients in Sb_(2)Te_(3)-GeTe superlattices.Sample orientation and excitation polarization dependences of the THz emission confirm that ultrafast thermo-electric,shift and injection currents contribute to the THz generation in Sb_(2)Te_(3)-GeTe superlattices.By decreasing the thickness and increasing the number of GeTe and Sb_(2)Te_(3) layer,the interlayer coupling can be enhanced,which significantly reduces the contribution from circular photo-galvanic effect(CPGE).A photo-induced bleaching in the transient reflectance spectroscopy probed in the range of~1100 nm to~1400 nm further demonstrates a gapped state resulting from the interlayer coupling.These demonstrates play an important role in the development of iPCM-based high-speed optoelectronic devices. 展开更多
关键词 Sb_(2)Te_(3)/GeTe superlattices ultrafast carrier dynamics interfacial phase change memory THz emission spectroscopy transient reflectance spectroscopy
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Nitrogen-Induced Change of Magnetic Properties in Antiperovskite-Type Carbide:Mn3InC
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作者 伊木然 孙莹 +3 位作者 邓司浩 史可文 胡鹏伟 王聪 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期159-163,共5页
The effects of N substitution on the magnetic properties of Mn3InC1-xNx (0.0≤ x ≤0.7) are investigated sys- tematically. Partial substitution of N for C leads to the monotonic reduction in both the Curie temperatu... The effects of N substitution on the magnetic properties of Mn3InC1-xNx (0.0≤ x ≤0.7) are investigated sys- tematically. Partial substitution of N for C leads to the monotonic reduction in both the Curie temperature Tc and saturated magnetization Ms. The final results obtained from thermo-magnetie curves demonstrate that Mn3InC1-xNx samples show a magnetic phase transition from a paramagnetic (PM) state to a ferrimagnetic (FIM) state consisting of ferromagnetic (FM) and antiferromagnetie (AFM) components. In addition, there is a competition between the AFM component and the FM component in the FIM state with the change of the N-doped content. Magnetic measurements of Mn3InC at 100 Oe and 5000 Oe indicate the metastability and the coexistence of different magnetic phases at lower temperature. The spans of FIM phase broaden gradually with further N doping. The mechanism for the induction of the complicated magnetic state is still in controversy. However, the results clearly show that the doping at the X site in antiperovskite Mn3AX materials is as useful as that of the A and Mn sites. 展开更多
关键词 Nitrogen-Induced change of Magnetic Properties in Antiperovskite-Type Carbide:Mn3InC FIM Mn AFM
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Improvement in refractive-index change in LiNbO3:Ce:Cu by applying an external electric field
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作者 戴翠霞 刘立人 +3 位作者 刘德安 周煜 柴志方 栾竹 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2491-2495,共5页
By jointly solving two-centre material equations with a nonzero external electric field and coupled-wave equations, we have numerically studied the dependence of the non-volatile holographic recording in LiNbO3:Ce:C... By jointly solving two-centre material equations with a nonzero external electric field and coupled-wave equations, we have numerically studied the dependence of the non-volatile holographic recording in LiNbO3:Ce:Cu crystals on the external electric field. The dominative photovoltaic effect of the non-volatile holographic recording in doubly doped LiNbO3 crystals is directly verified. And an external electric field that is applied in the positive direction along the c-axis (or a large one in the negative direction of the c-axis) in the recording phase and another one that is applied in the negative direction of the c-axis in the fixing phase are both proved to benefit strong photorefractive performances. Experimental verifications are given with a small electric field applied externally. 展开更多
关键词 non-volatile holographic recording external electric field refractive-index change LiNbO3:Ce:Cu crystals
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合水地区长6_(3)深水重力流沉积特征研究
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作者 车雨恒 魏钦廉 +5 位作者 陈曦 田伟 李小军 张洪军 赵爱彬 唐婧 《石油地质与工程》 CAS 2024年第2期58-65,共8页
合水地区是鄂尔多斯盆地近年来原油勘探的重点区块,在系统分析沉积构造、岩石学特征、结构粒度特征等沉积相识别标志的基础上,结合区域沉积背景,开展了合水地区长6_(3)重力流沉积类型及展布特征研究。结果表明,合水地区长6_(3)油层亚组... 合水地区是鄂尔多斯盆地近年来原油勘探的重点区块,在系统分析沉积构造、岩石学特征、结构粒度特征等沉积相识别标志的基础上,结合区域沉积背景,开展了合水地区长6_(3)重力流沉积类型及展布特征研究。结果表明,合水地区长6_(3)油层亚组为湖泊-重力流沉积体系,发育半深湖-深湖沉积亚相,可进一步划分为浊流沉积、砂质碎屑流、滑塌沉积三种重力流沉积类型;其中砂质碎屑流及浊流为主要控砂微相,主要分布在研究区的中部、南部区域,为区内有利储集相带。 展开更多
关键词 鄂尔多斯盆地合水地区 长6_(3)油层亚组 重力流沉积 砂质碎屑流 浊流
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Na_(2)CO_(3)·10H_(2)O-Na_(2)HPO_(4)·12H_(2)O/SiO_(2)复合定形相变材料的制备及应用
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作者 王璇 李再超 +2 位作者 吴亚楠 唐炳涛 张宇昂 《精细化工》 EI CAS CSCD 北大核心 2024年第3期623-629,656,共8页
以Na_(2)CO_(3)·10H_(2)O(SCD)、Na_(2)HPO_(4)·12H_(2)O(DHPD)为相变主体制备了共晶体系,通过绘制凝固点变化图与DSC测试共同确定在m(SCD)∶m(DHPD)=4∶6时形成共晶,FTIR和XRD结果显示,2种水合盐间没有发生化学反应,但其晶... 以Na_(2)CO_(3)·10H_(2)O(SCD)、Na_(2)HPO_(4)·12H_(2)O(DHPD)为相变主体制备了共晶体系,通过绘制凝固点变化图与DSC测试共同确定在m(SCD)∶m(DHPD)=4∶6时形成共晶,FTIR和XRD结果显示,2种水合盐间没有发生化学反应,但其晶型结构发生改变。通过添加质量分数为2%的Na2SiO3·9H_(2)O作为成核剂降低体系的过冷度,且经历50次相变循环体系未出现相分离,相变焓值仅下降0.25%。进一步使用质量分数为25%的气相SiO_(2)作为支撑材料,采用浸渍法制备了相变前后形状稳定的共晶水合盐/SiO_(2)定形相变材料(SSPCM)。所得SSPCM的相变温度为24.08℃,相变焓值为146.6J/g,过冷度为0.55℃,热导率为0.4571W/(m·K)。同保温泡沫相比,其可将模拟房内部中心温度的升温时间延长了1.81倍,降温时间延长了0.39倍。 展开更多
关键词 Na_(2)CO_(3)·10H_(2)O Na_(2)HPO_(4)·12H_(2)O 共晶水合盐 复合相变材料 建筑节能 功能材料
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E-64d对大鼠视网膜缺血再灌注损伤中Calpain和Caspase-3表达的调控作用 被引量:6
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作者 陈芝清 姚克 +2 位作者 徐雯 章征 朱雅琴 《眼科研究》 CSCD 北大核心 2007年第1期44-48,共5页
目的探讨E-64d(半胱氨酸蛋白酶抑制剂及钙激活中性蛋白酶抑制剂)在大鼠视网膜缺血再灌注损伤(RIRI)中对Calpain/Caspase-3表达的调节作用。方法将80只SD大鼠随机分为正常组、视网膜缺血再灌注组、对照组和E-64d治疗组,并分为1、3、6、24... 目的探讨E-64d(半胱氨酸蛋白酶抑制剂及钙激活中性蛋白酶抑制剂)在大鼠视网膜缺血再灌注损伤(RIRI)中对Calpain/Caspase-3表达的调节作用。方法将80只SD大鼠随机分为正常组、视网膜缺血再灌注组、对照组和E-64d治疗组,并分为1、3、6、24、72h5个时间段。通过前房穿刺加压法制成RIRI动物模型,采用Western-blot以及RT-PCR方法测定在大鼠RIRI模型中的Calpian、Caspase-3蛋白和mRNA表达情况。结果缺血再灌注24hm-Calpain、Caspase-3蛋白的表达缺血再灌注组较正常组上升,而E-64d组表达与正常组相似,比缺血再灌注组下降。E-64d能下调视网膜缺血再灌注后m-Calpain/Calpastatin的mRNA比值,在24h与缺血组有显著统计学差异。结论E-64d能降低视网膜缺血再灌注时m-Calpain、Caspase-3蛋白的表达,调控m-Calpain和Calpastatin的mRNA比值。 展开更多
关键词 e-64d 视网膜缺血再灌注损伤 CALPAIN CASPASe-3
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