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Reflectance conversion methods for the VIS/NIR imaging spectrometer aboard the Chang'E-3 lunar rover: based on ground validation experiment data

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Research in Astronomy and Astrophysics 2013年第7期13卷 862-874页

作者： Bin Liu Jian-Zhong Liu Guang-Liang Zhang Zong-Cheng Ling Jiang Zhang zhi-ping he Ben-Yong Yang Yong-Liao Zou National Astronomical Observatories Chinese Academy of Sciences School of Space Science and Physics Shandong University at Weihai Graduate University of Chinese Academy of Sciences Shanghai Institute of Technical Physics Chinese Academy of Sciences Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences

The second phase of the Chang＇E Program （also named Chang＇E-3） has the goal to land and perform in-situ detection on the lunar surface. A VIS/NIR imaging spectrometer （VNIS） will be carded on the Chang＇E-3 lunar rover to detect the distri-bution of lunar minerals and resources. VNIS is the first mission in history to perform in-situ spectral measurement on the surface of the Moon, the reflectance data of which are fundamental for interpretation of lunar composition, whose quality would greatly affect the accuracy of lunar element and mineral determination. Until now, in-situ de-tection by imaging spectrometers was only performed by rovers on Mars. We firstly review reflectance conversion methods for rovers on Mars （Viking landers, Pathfinder and Mars Exploration rovers, etc）. Secondly, we discuss whether these conversion methods used on Mars can be applied to lunar in-situ detection. We also applied data from a laboratory bidirectional reflectance distribution function （BRDF） using simu- lated lunar soil to test the availability of this method. Finally, we modify reflectance conversion methods used on Mars by considering differences between environments on the Moon and Mars and apply the methods to experimental data obtained from the ground validation of VNIS. These results were obtained by comparing reflectance data from the VNIS measured in the laboratory with those from a standard spectrometer obtained at the same time and under the same observing conditions. The shape and amplitude of the spectrum fits well, and the spectral uncertainty parameters for most samples are within 8%, except for the ilmenite sample which has a low albedo. In conclusion, our reflectance conversion method is suitable for lunar in-situ detection.

关键词： instrumentation: detectors - lunar in-situ detection: VNIS - re-flectance conversion: BRDF

Operating principles and detection characteristics of the Visible and Near-Infrared Imaging Spectrometer in the Chang'e-3

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Research in Astronomy and Astrophysics 2014年第12期14卷 1567-1577页

作者： zhi-ping he Bin-Yong Wang Gang Lü Chun-Lai Li Li-Yin Yuan Rui Xu Bin Liu Kai Chen Jian-Yu Wang Key Laboratory of Space Active Opto-Electronics Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences The Science and Application Center for Moon and Deep Space Exploration National Astronomical Observatories Chinese Academy of Sciences

The Visible and Near-Infrared Imaging Spectrometer （VNIS）, using two acousto-optic tunable filters as dispersive components, consists of a VIS/NIR imag- ing spectrometer （0.45-0.95 μm）, a shortwave IR spectrometer （0.9-2.4 p.m） and a calibration unit with dust-proofing functionality. The VNIS was utilized to detect the spectrum of the lunar surface and achieve in-orbit calibration, which satisfied the re- quirements for scientific detection. Mounted at the front of the Yutu rover, lunar ob- jects that are detected with the VNIS with a 45° visual angle to obtain spectra and ge- ometrical data in order to analyze the mineral composition of the lunar surface. After landing successfully on the Moon, the VNIS performed several explorations and cal- ibrations, and obtained several spectral images and spectral reflectance curves of the lunar soil in the region of Mare Imbrium. This paper describes the working principle and detection characteristics of the VNIS and provides a reference for data processing and scientific applications.

关键词： space vehicles: instruments -- instrumentation: spectrographs -- Moon-- techniques: spectroscopic

Reflectance calibration and shadow effect of VNIS spectra acquired by the Yutu rover

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Reflectance calibration and shadow effect of VNIS spectra ac...

Infrared spectra and normal coordinate analysis of trinuclear μ_3-oxoacetato complexes of chromium and iron

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Sen Hu Yang-Ting Lin Bin Liu Wei Yang zhi-ping he Wei-Fan Xing Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences 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 Technical Physics Chinese Academy of Sciences China University of Geosciences

Yutu is the first lunar rover after the Apollo program and Luna *** of the payloads on the Yutu rover,the Visible and Near-infrared Imaging Spectrometer(VNIS),has acquired four VIS/NIR images and SWIR spectra near its landing site in Mare *** radiance images were reduced through repairing bad lines and bad points,and applying flat field correction,and then were converted into reflectance values based on the solar irradiance and angles of incidence.A significant shadow effect was observed in the VIS/NIR *** shadowed regions show lower reflectance with a darkening trend compared with illuminated *** reflectance increased by up to 24%for entire images and 17%for the VIS/NIR-SWIR overlapping regions after shadow *** correction for the shadow effect will remarkably decrease the estimate of FeO content,by up to 4.9 wt.%in this *** derived Fe O contents of CD-005～008 after shadow correction are around 18.0 wt.%.

关键词： Moon Chang’e-3 Yutu VNIS shadow reflectance

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Acta Chimica Sinica English Edition 1989年第3期7卷 219-228页

作者： ZHANG Lin-Na LIU zhi-ping he Ling-Jie CAI Su-Hua JIAN Feng-Ying Fujian Institute of Research on the Structure of Matter,Academia Sinica,Fuzhou Fujian Institute of Research on the Structure of Matter Academia Sinica Fuzhou

The IR spectra of four u_3-oxo-acetato complexes of Cr(Ⅲ)and Fe(Ⅲ)are reported in this *** assignments of v(Cr-L)are made empirically by comparing the IR spectra of serial compounds and experimentally by carrying out a variable-temperature experiment in situ. A simplified model was employed for the normal coordinate analysis of two homo-nuclear skeletons and their force constants have been *** terms of the relationship between the IR spectra and their structure the rationality and reliability of the results are *** the same time the as- signments which are discordant in the references are checked by calculation and the more rational results have been obtained.

关键词： oxoacetato complexes of chromium and iron Cr

Positive effect of Mo on mechanical properties of a Ni-42W-10Co-x Mo medium heavy alloy

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China Foundry 2025年

作者： Guo-xin Cao Jian-xin Dong Yong-sheng he he Jiang Fang Hao zhi-hua Nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology Beijing Xi'an Superalloy Technology Co. Ltd. School of Materials Science and Engineering Beijing Institute of Technology Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou University

In this study,a novel Ni-W-Co-Mo medium heavy alloy (MHA) was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-xM o alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypoeutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-xM o alloys is Mo-induced solid solution strengthening and precipitation strengthening.

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Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang Si Liu YiHua he Chang Yang YuYue Jin ZhouKun Deng ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

Reconstructing forest and grassland cover changes in China over the past millennium

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Science China Earth Sciences 2025年第1期68卷 94-110页

作者： Fanneng he Fan YANG Yafei WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and Sustainable Development Henan University University of Chinese Academy of Sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “S” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. Subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： Di Zhang Pengfei Lv Wei Qin Xin he Yuanhua he Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability

Breaking new ground in photocatalysis: lutetium texaphyrin as a trigger for pyroptosis through biomolecular photoredox reactions

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Science China Chemistry 2025年第1期68卷 1-2页

作者： Qihang Ding Mengrong he Meijia Gu Department of Chemistry Korea University Department of Ultrasound Medicine Union Hospital Tongji Medical College Huazhong University of Science and Technology Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (MOE) School of Pharmaceutical Sciences Wuhan University

Malignant neoplasms consistently pose a significant threat to global public health [1,2]. In recent years, immunotherapy has demonstrated remarkable clinical success; however, its efficacy is limited by the scarcity of immune cell infiltration within tumor microenvironments. Cell pyroptosis, a gasdermin-mediated process characterized by cellular swelling,rupture, and the release of intracellular contents such as IL-1β, IL-18, ATP, HMGB1, plays a crucial role in this context[3,4].

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