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Science China(Life Sciences) 2023年第6期66卷 1426-1439页

作者： Jiachao Zhou Thomas W Kuyper Gu Feng College of Resources and Environmental Sciences China Agricultural UniversityBeijing100193China Soil Biology Group Wageningen University&ResearchWageningen6700 AAThe Netherlands

Ecology seeks to explain species coexistence,but experimental tests of mechanisms for coexistence are difficult to *** synthesized an arbuscular mycorrhizal(AM)fungal community with three fungal species that differed in their capacity of foraging for orthophosphate(P)due to differences in soil *** tested whether AM fungal species-specific hyphosphere bacterial assemblages recruited by hyphal exudates enabled differentiation among the fungi in the capacity of mobilizing soil organic P(P_(o)).We found that the less efficient space explorer,Gigaspora margarita,obtained less ^(13)C from the plant,whereas it had higher efficiencies in P_(o)mobilization and alkaline phosphatase(Al Pase)production per unit C than the two efficient space explorers,Rhizophagusintraradices and Funneliformis *** AM fungus was associated with a distinct alp gene harboring bacterial assemblage,and the alp gene abundance and P_(o)preference of the microbiome associated with the less efficient space explorer were higher than those of the two other *** conclude that the traits of AM fungal associated bacterial consortia cause niche *** trade-off between foraging ability and the ability to recruit effective P_(o)mobilizing microbiomes is a mechanism that allows co-existence of AM fungal species in a single plant root and surrounding soil habitat.

关键词： arbuscular mycorrhizal fungi carbon space exploration hyphosphere bacterial assemblages organic phosphorus mobilization

space exploration—a Good or Bad Thing?

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新高考(英语进阶) 2014年第3期 4-4页

作者：郑林茂

2013年12月15日中国"嫦娥三号"携带"玉兔"号月球车成功着陆月球,揭开了中国探索太空的新篇章。太空探索一直都伴随着人类的历史发展,但是对于太空探索的争论也一直不断。有人认为太空探索花费太高,不能对民众的生活带来实质的影响;有人... 详细信息

2013年12月15日中国"嫦娥三号"携带"玉兔"号月球车成功着陆月球,揭开了中国探索太空的新篇章。太空探索一直都伴随着人类的历史发展,但是对于太空探索的争论也一直不断。有人认为太空探索花费太高,不能对民众的生活带来实质的影响;有人认为太空探索带来技术的革新,为人类"星际旅行"打下基础。那么太空探索到底是好还是坏呢?

关键词： Bad space exploration a Good or Bad Thing 太空探索

Strategic Study on the Development of space Science in China and Proposals for Future Missions

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空间科学学报 2024年第4期44卷 699-703页

作者： WANG Chi SONG Tingting LI Ming CAO Song National space Science Center Chinese Academy of SciencesBeijing 100190

Since 2011,the Chinese Academy of Sciences(CAS)has implemented the Strategic Priority Program on space Science(SPP).A series of scientific satellites have been developed and launched,such as Dark Matter Particle Explorer(DAMPE),Quantum Experiments at space Scale(QUESS),Advanced space-based Solar Observatory(ASO-S),Einstein Probe(EP),and significant scientific outcomes have been *** order to plan the future space science missions in China,CAS has organized the Chinese space science community to conduct medium and long-term development strategy studies,and summarized the major scientific frontiers of space science as“One Black,Two Dark,Three Origins and Five Characterizations”.Five main scientific themes have been identified for China’s future breakthroughs,including the Extreme Universe,space-Time Ripples,the Panoramic View of the Sun and Earth,the Habitable Planets,and Biological&Physical Science in *** science satellite missions to be implemented before 2030 are proposed accordingly.

关键词： space science space missions space exploration

Attaining the liquid helium temperature with a compact pulse tube cryocooler for space applications

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Science China(Technological Sciences) 2020年第3期63卷 434-439页

作者： LIU XuMing CHEN LiuBiao WU XianLin YANG Biao WANG Jue ZHU WenXiu WANG JunJie ZHOU Yuan Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Recent breakthroughs in space science have motivated space exploration programs in many countries including China. Cryocoolers, which provide the mandatory low-temperature environment for many sensitive yet delicate space detectors, are crucial for the proper functioning of various systems. One benchmark for the cryocooler performance is attaining the liquid helium temperature. However, even with complex configurations and multiple driving sources, only a few cryocoolers to date can achieve this goal. Here we report a high-frequency pulse tube cryocooler(HPTC) driven by a single non-oil-lubrication compressor which is capable of reaching the liquid helium temperature while offering other advantages such as high compactness, excellent reliability and high efficiency. The HPTC obtains a no-load temperature of 4.4 K, which is the first realization of cooling below the4 He critical point with a gas-coupled two-stage arrangement. The prototype can provide a cooling power of 87 mW at 8 K, and 5.2 mW at 5 K with a 425 W input electric power, showing leading-level efficiency. Moreover, we demonstrate the ability of the cryocooler to simultaneously provide cooling power at different temperature levels to meet different requirements. Therefore, the prototype developed here could be a promising cryocooler for space applications and beyond.

关键词： cryocooler liquid helium temperature space exploration high frequency

Preparation and Characterization of High-Strength Geopolymer Based on BH-1 Lunar Soil Simulant with Low Alkali Content

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Engineering 2021年第11期7卷 1631-1645页

作者： Siqi Zhou Chenghong Lu Xingyi Zhu Feng Li School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China

The construction of a lunar base and habitation on the Moon has always been on researchers’*** materials used in in situ lunar resources are of great significance for saving expensive space *** this study,a new type of lunar soil simulant named Beihang(BH)-1 was *** chemical mineral composition and microstructure of BH-1 closely resemble those of real lunar soil,as verified by X-ray fluorescence spectroscopy(XRF),X-ray diffraction(XRD),scanning electron microscopy(SEM),and reflectance *** research also synthesized a geopolymer based on BH-1 cured at simulated lunar atmospheric *** also investigated the effect of supplementing aluminum(Al)sources on the enhancement of geopolymer strength based on *** rheological behavior of alkali-activated BH-1 pastes was determined for ***,XRD,Fourier transform infrared spectroscopy,SEM coupled with energy dispersive spectroscopy,and 27Al magic angle spinningnuclear magnetic resonance were used to characterize resulting *** test findings showed that the rheology of BH-1 pastes fits the Herschel–Bulkley model,and they behaved like a shear-thinning *** results showed that the 28-day compressive strength of the BH-1 geopolymer was improved by up to 100.8%.Meanwhile,the weight of additives required to produce per unit strength decreased,significantly reducing the mass of materials transported from the Earth for the construction of lunar infrastructure and saving space transportation *** analyses showed that the mechanism to improve the mechanical properties of the BH-1 geopolymer by adding an additional Al source enhances the replacement of silicon atoms by Al atoms in the silicon–oxygen group and generates a more complete and dense amorphous gel structure.

关键词： space exploration Lunar base Geopolymer Lunar soil simulant Rheology

Motion modeling and formation form analysis of spacecraft near collinear libration points

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Journal of Harbin Institute of Technology(New Series) 2009年第5期16卷 687-692页

作者：崔平远李鹏崔祜涛 Deep space exploration Research Center Harbin Institute of Technology

To meet the increasing research demand for deep space exploration,especially for the second libration point (L2) conditional periodic orbit (Halo orbit) in the Sun-Earth system,the methods to get analytical Halo orbit and differential-correction Halo orbit were described firstly,and the corresponding orbits accuracy was ***,based on the results of third-order and differential-correction Halo orbits,the formation form was *** was carried out to discuss the influence of system amplitude,initial phase,and phase difference on the formation form,as well as that of initial orbit values on form ***,some simulation results demonstrate the validity of the proposed methods.

关键词： space exploration collinear libration point Halo orbit formation flying form analytical solution and differential-correction

China's space Science Program(2025-2030):Strategic Priority Program on space Science(Ⅲ)

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空间科学学报 2022年第4期42卷 514-518页

作者： WANG Chi SONG Tingting SHI Peng LI Ming FAN Quanlin National space Science Center Chinese Academy of SciencesBeijing100190

The Strategic Priority Program(SPP)on space Science,which is under the leadership of the Chinese Academy of Sciences(CAS),has established China’s space science satellite series from scratch.A number of major scientific achievements have been made by the first phase of the Program(SPPⅠ),while SPPⅡhas been currently being *** future development of space science needs urgent top-level planning and advanced layout to clarify the overall goal and investment portfolio from 2025 to *** will briefly introduce the initiative and possible space science missions of SPPⅢ,including the preparatory work which already started in July *** the effective administrative tradition since SPPⅠ,National space Science Center(NSSC,CAS)is responsible for the whole procedure,including soliciting,assessment,and implementation of SPPⅢ.Brief information on the 13 candidate missions will be described,including missions in the fields of astronomy&astrophysics,exoplanets,heliophysics and planetary&Earth science,respectively.

关键词： space science Strategic Priority Program(SPP) space science missions space exploration

Analysis of Growth Characteristics and Differentially Expressed Homologous Genes in Rhodobacter sphaeroides under Normal and Simulated Microgravity Conditions

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Advances in Microbiology 2023年第11期13卷 539-558页

作者： Weerakkody Ranasinghe Eduardo Gutierrez Zelaya Alyson Sabrina Vazquez Ashleigh Ogg Rajesh Prabhu Balaraman Hyuk Cho Madhusudan Choudhary Department of Biological Sciences Sam Houston State University Huntsville Texas USA Department of Computer Science Sam Houston State University Huntsville Texas USA

The term “microgravity” is used to describe the “weightlessness” or “zero-g” circumstances that can only be found in space beyond earth’s atmosphere. Rhodobacter sphaeroides is a gram-negative purple phototroph, used as a model organism for this study due to its genomic complexity and metabolic versatility. Its genome has been completely sequenced, and profiles of the differential gene expression under aerobic, semi-aerobic, and photosynthetic conditions were examined. In this study, we hypothesized that R. sphaeroides will show altered growth characteristics, morphological properties, and gene expression patterns when grown under simulated microgravity. To test that, we measured the optical density and colony-forming units of cell cultures grown under both microgravity and normal gravity conditions. Differences in the cell morphology were observed using scanning electron microscopy (SEM) images by measuring the length and the surface area of the cells under both conditions. Furthermore, we also identified homologous genes of R. spheroides using the differential gene expression study of Acidovorax under microgravity in our laboratory. Growth kinetics results showed that R. sphaeroides cells grown under microgravity experience a shorter log phase and early stationary phase compared to the cells growing under normal gravity conditions. The length and surface area of the cells under microgravity were significantly higher confirming that bacterial cells experience altered morphological features when grown under microgravity conditions. Differentially expressed homologous gene analysis indicated that genes coding for several COG and GO functions, such as metabolism, signal-transduction, transcription, translation, chemotaxis, and cell motility are differentially expressed to adapt and survive microgravity.

关键词： Simulated Microgravity Differential Gene Expression Bacteria Gene Homology space exploration

The Truth behind the Solar System in the Universe

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Advances in Aerospace Science and Technology 2021年第3期6卷 158-169页

作者： Rami Ayoob University of Bahrain Manama Kingdom of Bahrain

This research focuses on multiple facts regarding the earth gravity and the space mechanism, mainly on the solar systems including the Sun and the planets belonging to it. Our solar system consists of our star, the Sun, and everything bound to it by gravity based on Albert Einstein and Isaac Newton theories. The planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto, dozens of moons, millions of asteroids, Comets and meteoroids [1]. Also, it will discuss about The Geocentric model and how scientifically proofed that the Earth is not orbiting the sun as it has a fixed position in the universe with the rotation around its axis and the sun is orbiting the Earth in one solar year. The output of the Geocentric model led to that the gravity is a feature generated by the planet itself to be measured reference to the weight granted to the matter.

关键词： Astronomy Deep space Earth Sun Galaxy Gravitation Heliocentric Model Geocentric Model Orbit Planet Solar System space exploration Sidereal

Automatic Instruction Generation for Application Specific Co-processor

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Automatic Instruction Generation for Application Specific Co...