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Stagnant lid tectonics:Perspectives from silicate planets,dwarf planets, large moons,and large asteroids 被引量:18
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作者 Robert J.Stern Taras Gerya Paul J.Tackley 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第1期103-119,共17页
To better understand Earth's present tectonic style-plate tectonics—and how it may have evolved from single plate(stagnant lid) tectonics, it is instructive to consider how common it is among similar bodies in th... To better understand Earth's present tectonic style-plate tectonics—and how it may have evolved from single plate(stagnant lid) tectonics, it is instructive to consider how common it is among similar bodies in the Solar System. Plate tectonics is a style of convection for an active planetoid where lid fragment(plate) motions reflect sinking of dense lithosphere in subduction zones, causing upwelling of asthenosphere at divergent plate boundaries and accompanied by focused upwellings, or mantle plumes;any other tectonic style is usefully called "stagnant lid" or "fragmented lid". In 2015 humanity completed a 50+ year effort to survey the 30 largest planets, asteroids, satellites, and inner Kuiper Belt objects,which we informally call "planetoids" and use especially images of these bodies to infer their tectonic activity. The four largest planetoids are enveloped in gas and ice(Jupiter, Saturn, Uranus, and Neptune)and are not considered. The other 26 planetoids range in mass over 5 orders of magnitude and in diameter over 2 orders of magnitude, from massive Earth down to tiny Proteus; these bodies also range widely in density, from 1000 to 5500 kg/m^3. A gap separates 8 silicate planetoids with ρ = 3000 kg/m^3 or greater from 20 icy planetoids(including the gaseous and icy giant planets) with ρ = 2200 kg/m^3 or less. We define the "Tectonic Activity Index"(TAI), scoring each body from 0 to 3 based on evidence for recent volcanism, deformation, and resurfacing(inferred from impact crater density). Nine planetoids with TAI = 2 or greater are interpreted to be tectonically and convectively active whereas 17 with TAI <2 are inferred to be tectonically dead. We further infer that active planetoids have lithospheres or icy shells overlying asthenosphere or water/weak ice. TAI of silicate(rocky) planetoids positively correlates with their inferred Rayleigh number. We conclude that some type of stagnant lid tectonics is the dominant mode of heat loss and that plate tectonics is unusual. To make progress understanding Earth's tectonic history and the tectonic style of active exoplanets, we need to better understand the range and controls of active stagnant lid tectonics. 展开更多
关键词 Stagnant LID Solar system Plate TECTONICS Planets moons
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Many Moons Ago
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《小学生时代(大嘴英语)》 2025年第10期26-29,共4页
从古至今,月亮一直承载着人们对团圆的美好向往。英文中同样藏着许多与月亮有关的诗意表达。这一次,我们烙与M豆一起穿越古今,学习更多与冃亮不肝寸间有关的新表达。
关键词 月亮 Many moons Ago
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Numerical simulations on origin of Galilean moons' magnetic anomalies 被引量:1
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作者 JIAO LiGuo KUANG WeiJia MA ShiZhuang 《Science China Earth Sciences》 SCIE EI CAS 2011年第11期1754-1760,共7页
Galileo mission detected the magnetic anomalies originated from Galilean moons.These anomalies are likely generated in the moons' interiors,under the influence of a strong ambient Jovian field.Among various possib... Galileo mission detected the magnetic anomalies originated from Galilean moons.These anomalies are likely generated in the moons' interiors,under the influence of a strong ambient Jovian field.Among various possible generation mechanisms of the anomalies,we focus on magneto-convection and dynamos in the interiors via numerical simulation.To mimic the electromagnetic environment of the moons,we introduce in our numerical model an external uniform magnetic field B0 with a fixed orientation but varying field strength.Our results show that a finite B0 can substantially alter the dynamo processes inside the core.When the ambient field strength B0 increases to approximately 40% of the field generated by the pure dynamo action,the convective state in the core changes significantly:the convective flow decreases by 80% in magnitude,but the differential rotation becomes stronger in much of the fluid layer,leading to a stronger field generated in the core.The field morphologies inside the core tend to align with the ambient field,while the flow patterns show the symmetry-breaking effect under the influence of B0.Furthermore,the generated field tends to be temporally more stable. 展开更多
关键词 Galilean moons magnetic fields magneto-convection DYNAMO
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Covariance analysis of periodic and quasi-periodic orbits around Phobos with applications to the Martian Moons eXploration mission 被引量:1
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作者 Edoardo Ciccarelli Nicola Baresi 《Astrodynamics》 CSCD 2023年第3期363-379,共17页
Understanding the internal composition of a celestial body is fundamental for formulating theories regarding its origin.Deep knowledge of the distribution of mass under the body’s crust can be achieved by analyzing i... Understanding the internal composition of a celestial body is fundamental for formulating theories regarding its origin.Deep knowledge of the distribution of mass under the body’s crust can be achieved by analyzing its moments of inertia and gravity field.In this regard,the two moons of the Martian system have not yet been closely studied and continue to pose questions regarding their origin to the space community;thus,they deserve further characterization.The Martian Moons eXploration mission will be the first of its kind to sample and study Phobos over a prolonged period.This study aims to demonstrate that the adoption of periodic and quasi-periodic retrograde trajectories would be beneficial for the scientific value of the mission.Here,a covariance analysis was implemented to compare the estimation of high-order gravitational field coefficients from different orbital geometries and for different sets of processed observables.It was shown that the adoption of low-altitude non-planar quasi-satellite orbits would help to refine the knowledge of the moon’s libration angle and gravitational field. 展开更多
关键词 covariance analysis Martian system GEODETIC navigation Martian moons eXploration(MMX) PHOBOS
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Icy planets and moons bypassing the habitable state
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《Science Foundation in China》 CAS 2017年第4期21-,共1页
Profs.Yang Jun(杨军)and Hu Yongyun(胡永云)at the Department of Atmospheric and Oceanic Sciences,School of Physics,Peking University,and their collaborators recently published a paper in Nature Geoscience(http://www.na... Profs.Yang Jun(杨军)and Hu Yongyun(胡永云)at the Department of Atmospheric and Oceanic Sciences,School of Physics,Peking University,and their collaborators recently published a paper in Nature Geoscience(http://www.nature.com/ngeo/journal/v10/n8/pdf/ngeo2994.pdf).They show 展开更多
关键词 Icy planets and moons bypassing the habitable state NATURE WWW
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土卫家族再添128 星
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作者 彭向梅 《疯狂英语(初中天地)》 2025年第6期44-45,共2页
Astronomers(天文学家)have discovered 128 new moons orbiting the planet Saturn.Now Saturn has 274 moons in total.Saturn holds the title“king of the moons”because it’s the planet with the most moons in our solar syst... Astronomers(天文学家)have discovered 128 new moons orbiting the planet Saturn.Now Saturn has 274 moons in total.Saturn holds the title“king of the moons”because it’s the planet with the most moons in our solar system(太阳系).Jupiter(木星)comes in second with 95 known moons. 展开更多
关键词 solar system moons JUPITER SATURN
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The Origin of Rings
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作者 Mark Linick 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期19-27,共9页
The origin of rings is one of the final arguments in a series explaining solar system formation. Liquid moons placed in circular orbits close to the planet (inside the Roche limit) will deposit ring material as they m... The origin of rings is one of the final arguments in a series explaining solar system formation. Liquid moons placed in circular orbits close to the planet (inside the Roche limit) will deposit ring material as they migrate. Once outside the limit, moons retain this material. Finally, the shape of the moon, Pan, is explained, using the same mechanism that forms rings. 展开更多
关键词 LIQUID moons Roche Limit
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磁控溅射制备MoON薄膜电极及其电化学储能性质
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作者 万志鑫 余威 +2 位作者 张敏轩 徐格 冒爱琴 《高等学校化学学报》 北大核心 2025年第12期88-96,共9页
采用磁控溅射法制备了具有梯度氧含量的MoON薄膜材料,研究了制备过程中N_(2)/O_(2)分压对MoON薄膜微观结构、晶型、化学键合、导电性以及电化学储能性质的影响.结果表明,在优化氧含量下,当Ar/N_(2)/O_(2)的流量(sccm)比为240∶50∶10时,... 采用磁控溅射法制备了具有梯度氧含量的MoON薄膜材料,研究了制备过程中N_(2)/O_(2)分压对MoON薄膜微观结构、晶型、化学键合、导电性以及电化学储能性质的影响.结果表明,在优化氧含量下,当Ar/N_(2)/O_(2)的流量(sccm)比为240∶50∶10时,MoON薄膜电极材料展现出最优的电化学储能性质,在1 mol/L Na_(2)SO_(4)溶液中,其面积比电容从纯MoN薄膜电极的134 mF/cm^(2)提升至211 mF/cm^(2),增加了57.5%,而且具有优异的循环稳定性,在充放电10000次之后电容量没有衰减. 展开更多
关键词 MoON薄膜 磁控溅射 薄膜电极 电化学储能性质
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Two probes head to the Moon for water search
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作者 韩宁 《疯狂英语(新悦读)》 2025年第7期41-43,78,共4页
1 If astronauts want to stay on the Moon for more than a few days,they must find local resources,and water is one of the most crucial ones.Scientists believe there's water on the Moon,but they're unsure of whe... 1 If astronauts want to stay on the Moon for more than a few days,they must find local resources,and water is one of the most crucial ones.Scientists believe there's water on the Moon,but they're unsure of where it lies.2 Two probes are on their way to the Moon to solve this mystery.They will be launched on the same SpaceX Falcon 9 rocket from Cape Canaveral.If everything goes as planned,the first probe to reach the Moon will be Athena.Timothy Crain,the chief technology officer of Intuitive Machines,says it will take about 3 to 4 days,depending on the launch time.They'll orbit the Moon for 2 to 3 days to wait for the Sun to reach the landing site,because the lander's solar panels need sunlight to generate power.It only takes about 15 minutes to land softly after the engine is started. 展开更多
关键词 SpaceX Falcon WATER intuitive machinessays ATHENA MOON probes spacex falcon rocket ASTRONAUTS
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A promising view to the Moon:Anticipations for Tianwen-2 samples returned from Kamo’oalewa
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作者 WenZhe Li Yong Wei +1 位作者 Jian-Yang Li Wei Yang 《Earth and Planetary Physics》 2025年第4期782-788,共7页
The exploration of asteroids has received increasing attention since the 1990s because of the unique information these objects contain about the history of the early solar system.Quasi-satellites are a population of a... The exploration of asteroids has received increasing attention since the 1990s because of the unique information these objects contain about the history of the early solar system.Quasi-satellites are a population of asteroids that co-orbit closely with,but are outside the gravitational control of,the planet.So far,only five Earth quasi-satellites have been recognized,among which(469219)Kamo’oalewa(provisionally designated as 2016 HO3)is currently considered the most stable and the closest of these.However,little is known about this particular asteroid or this class of near-Earth asteroids because of the difficulties of observing them.China has announced that Tianwen-2,the asteroid sample-return mission to Kamo’oalewa,will be launched in 2025.Here,we review the current knowledge of Kamo’oalewa in terms of its physical characteristics,dynamic evolution,surface environment,and origin,and we propose possible breakthroughs that the samples could bring concerning the asteroid Kamo’oalewa as an Earth quasi-satellite.Confirming the origin of Kamo’oalewa,from its prevailing provenance as debris of the Moon,could be a promising start to inferring the evolutionary history of the Moon.This history would probably include a more comprehensive view of the lunar farside and the origin of the asymmetry between the two sides of the Moon.Comparing the samples from the Moon and Kamo’oalewa would also provide new insights into the Earth wind. 展开更多
关键词 Tianwen-2 Kamo’oalewa(2016 HO_(3)) returned samples evolutionary history of the Moon the Earth–Moon system
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WORLD NEWS
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《ChinAfrica》 2025年第10期12-13,共2页
ITALY A crescent moon rises at sunset behind Monte Camicia in Teramo on 3 September US A dog rides the waves with its trainer during the 20th annual Surf Dog Surf-a-Thon in Del Mar,California,on 7 September.
关键词 surf dog surf thon monte camicia WAVES teramo crescent moon sunset
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Space weathering characteristics of lunar permanently shadowed regions soils:Evidence from experimental simulation
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作者 Zixuan Han Yang Li +7 位作者 Chen Li Ronghua Pang Sizhe Zhao Zhuang Guo Kairui Tai Rui Li Zhenhao Hu Li Liu 《Acta Geochimica》 2025年第1期1-10,共10页
Permanently shadowed regions(PSRs)on the Moon are potential reservoirs for water ice,making them hot spots for future lunar exploration.The water ice in PSRs would cause distinctive changes in space weathering there,i... Permanently shadowed regions(PSRs)on the Moon are potential reservoirs for water ice,making them hot spots for future lunar exploration.The water ice in PSRs would cause distinctive changes in space weathering there,in particular reduction-oxidation processes that diff er from those in illuminated regions.To determine the characteristics of products formed during space weathering in PSRs,the lunar meteorite NWA 10203 with artifi cially added water was irradiated with a nanosecond laser to simulate a micro-meteorite bombardment of lunar soil containing water ice.The TEM results of the water-incorporated sample showed distinct amorphous rims that exhibited irregular thickness,poor stratifi cation,the appearance of bubbles,and a reduced number of npFe^(0).Additionally,EELS analysis showed the presence of ferric iron at the rim of the nanophase metallic iron particles(npFe^(0))in the amorphous rim with the involvement of water.The results suggest that water ice is another possible factor contributing to oxidation during micrometeorite bombardment on the lunar surface.In addition,it off ers a reference for a new space weathering model that incorporates water in PSRs,which could be widespread on asteroids with volatiles. 展开更多
关键词 Space weathering Permanently shadowed regions The Moon laser irradiation Water ice
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A GALLERY OF PEOPLE AND PLACES
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《ChinAfrica》 2025年第8期12-13,共2页
GREECE A full moon rises behind the Temple of Poseidon in Sounion on 10 July GERMANY Visitors attend the CosDay anime convention in Frankfurt on 5 July CROATIA A ceremonial parade is held at the 59th#akovo Embroidery ... GREECE A full moon rises behind the Temple of Poseidon in Sounion on 10 July GERMANY Visitors attend the CosDay anime convention in Frankfurt on 5 July CROATIA A ceremonial parade is held at the 59th#akovo Embroidery Festival in#akovo on 6 July。 展开更多
关键词 akovo embroidery festival full moon sounion ceremonial parade cosday anime convention temple poseidon FRANKFURT
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基于NT-Xent损失函数优化的MOON算法在图像处理中的应用研究
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作者 詹睿 《信息与电脑》 2025年第11期4-6,共3页
如今机器学习发展得很快,可处理高维图像数据时,训练过程麻烦不断。特别是在多设备协作场景下,既要保护数据隐私不泄露,又得解决不同设备数据分布不均衡的问题,这都成了研究难点。老一套集中式深度学习方法,在隐私保护这块有明显短板,... 如今机器学习发展得很快,可处理高维图像数据时,训练过程麻烦不断。特别是在多设备协作场景下,既要保护数据隐私不泄露,又得解决不同设备数据分布不均衡的问题,这都成了研究难点。老一套集中式深度学习方法,在隐私保护这块有明显短板,很难满足当下需求。这篇文章重点研究模型对比联邦学习(Model-Contrastive Federated Learning,MOON)算法在图像处理里的应用和改进。先是把MOON算法复现出来,在通用数据集上跑实验,和其他算法对比性能,看看它到底强在哪、弱在哪。针对发现的问题,提出专门的优化方案,目标就是提升算法处理复杂异构数据的能力。从实验结果来看,优化后的MOON算法确实给力,不管是图像分类还是目标检测任务,训练时收敛速度变快了,遇到新数据也能更好地适应,泛化能力明显增强。这一成果,给联邦学习在隐私保护和异构数据处理方向的研究,提供了新的思路和参考。 展开更多
关键词 NT-Xent损失函数 MOON算法 机器学习 图像处理 异构数据处理
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Detecting the Lunar Wrinkle Ridges Through Deep Learning Based on DEM and Aspect Data
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作者 Xin Lu Jiacheng Sun +2 位作者 Gaofeng Shu Jianhui Zhao Ning Li 《Research in Astronomy and Astrophysics》 2025年第8期167-179,共13页
Lunar wrinkle ridges are an important stress geological structure on the Moon, which reflect the stress state and geological activity on the Moon. They provide important insights into the evolution of the Moon and are... Lunar wrinkle ridges are an important stress geological structure on the Moon, which reflect the stress state and geological activity on the Moon. They provide important insights into the evolution of the Moon and are key factors influencing future lunar activity, such as the choice of landing sites. However, automatic extraction of lunar wrinkle ridges is a challenging task due to their complex morphology and ambiguous features. Traditional manual extraction methods are time-consuming and labor-intensive. To achieve automated and detailed detection of lunar wrinkle ridges, we have constructed a lunar wrinkle ridge data set, incorporating previously unused aspect data to provide edge information, and proposed a Dual-Branch Ridge Detection Network(DBR-Net) based on deep learning technology. This method employs a dual-branch architecture and an Attention Complementary Feature Fusion module to address the issue of insufficient lunar wrinkle ridge features. Through comparisons with the results of various deep learning approaches, it is demonstrated that the proposed method exhibits superior detection performance. Furthermore, the trained model was applied to lunar mare regions, generating a distribution map of lunar mare wrinkle ridges;a significant linear relationship between the length and area of the lunar wrinkle ridges was obtained through statistical analysis, and six previously unrecorded potential lunar wrinkle ridges were detected. The proposed method upgrades the automated extraction of lunar wrinkle ridges to a pixel-level precision and verifies the effectiveness of DBR-Net in lunar wrinkle ridge detection. 展开更多
关键词 MOON methods:data analysis planets and satellites:surfaces techniques:image processing
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Ownership of Mineral Resources in Outer Space
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作者 Kassim B.Kipanga Taw-Wong Youyod 《Aerospace China》 2025年第2期55-68,共14页
Ownership is an increasingly important conflict in outer space at this moment in time.Despite the principle in the Outer Space Treaty(1967),that emphasizes the importance of all states'free access to outer space b... Ownership is an increasingly important conflict in outer space at this moment in time.Despite the principle in the Outer Space Treaty(1967),that emphasizes the importance of all states'free access to outer space based on equality for exploration and use.Moreover,outer space including the Moon and other celestial bodies is not subject to national appropriation by claim of sovereignty,by means of use or occupation,or by any other means.However,outer space activity is not free from sovereignty and jurisdiction after all.Anyway,the legal situation relating to space resource exploitation and utilization activities under the adoption of United Nations is a challenge.Some scholars implied that the Outer Space Treaty(1967)clearly prohibits appropriation of whole celestial bodies but is far less clear concerning the rights of over-extracted resources.Nevertheless,the Moon Agreement(1979)promotes the idea of property ownership of over-extracted resources.It permits states to collect and remove samples of lunar minerals and other substances for further interest in scientific investigation.The application of the Moon Agreement(1979)is not only to the Moon itself but to other celestial bodies,thus potentially covering the planets and asteroids where the mining potential is considered to be limitless.Under this circumstance,numerous countries,such as the United States,Luxembourg,The United Arab Emirates,and Japan have enacted legal regimes that glorify the rights of their entities in mineral resources in outer space.However,these regimes could be disputed under the international legal framework if countries have merely interpreted and applied their rights and obligations on a national level as they understand them.Therefore,this paper purports to clarify the ownership rights in outer space and analyze the purpose of the legal situation relating to space resource exploitation and utilization activities under the adoption of the United States,Luxembourg,The United Arab Emirates,and Japan. 展开更多
关键词 Outer Space Treaty(1967) Moon Agreement(1979) mineral resources in outer space
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Once in a blue moon
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作者 姜颖 《疯狂英语(初中天地)》 2025年第3期46-47,共2页
我们可能在英语影视剧、文学作品中看到过一个短语叫“once in ablue moon”,这个短语用来描述很少发生的事件或情况,意味着某件事非常罕见,你可能很长时间都遇不到一次。例如,如果一个人偶尔玩一次游戏,你可以说他们“play games once ... 我们可能在英语影视剧、文学作品中看到过一个短语叫“once in ablue moon”,这个短语用来描述很少发生的事件或情况,意味着某件事非常罕见,你可能很长时间都遇不到一次。例如,如果一个人偶尔玩一次游戏,你可以说他们“play games once in a blue moon”。 展开更多
关键词 once in a blue moon
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月球的地体构造与起源模式 被引量:6
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作者 刘建忠 欧阳自远 +2 位作者 张福勤 李春来 邹永廖 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第8期2011-2016,共6页
按照月球表面物质成分分布的特点,月壳可以划分为三个主要的化学地体:1)风暴洋克里普地体(PKT);2)斜长质高地地体(FHT);3)南极爱特肯地体(SPAT),综合对比天体化学和固体地球科学研究的前缘和热点,本文建立了月球地体构造及其起源的星子... 按照月球表面物质成分分布的特点,月壳可以划分为三个主要的化学地体:1)风暴洋克里普地体(PKT);2)斜长质高地地体(FHT);3)南极爱特肯地体(SPAT),综合对比天体化学和固体地球科学研究的前缘和热点,本文建立了月球地体构造及其起源的星子堆积模式,对月球化学分布的不均匀性的起因给出了较为简单和合理的解释。 展开更多
关键词 月球表面 地体构造 源模式 the MOON accumulation model 天体化学 地球科学研究 EXPLANATION structure 综合对比 成分分布 堆积模式 不均匀性 research origin FHT three found 星子 物质
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磁共振波谱技术及其在神经科学研究领域中的应用 被引量:5
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作者 侯莉娟 刘晓莉 乔德才 《中国康复医学杂志》 CAS CSCD 北大核心 2010年第12期1207-1210,共4页
1973年Moon和Richard等利用磁共振波谱分析(magnetic resonance spectroscopy,MRS)技术对离体红细胞的特征物质变化进行了测定。这一研究成为MRS技术在生物学领域应用的开端。
关键词 磁共振波谱技术 科学研究 应用 磁共振波谱分析 RICHARD 神经 MOON 红细胞
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中秋月饼考 被引量:2
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作者 黄涛 王心愿 《温州大学学报(社会科学版)》 2014年第2期33-41,共9页
关于中秋月饼产生的时间和原因,有多种说法。经过文献考证可知,中国饼食的制作有古远的历史,而月饼的前身是汉代以来的胡饼。关于中秋月饼产生于唐代和宋代的说法都是没有确凿依据的。有充分资料证明,作为中秋节节令食品的月饼正式出现... 关于中秋月饼产生的时间和原因,有多种说法。经过文献考证可知,中国饼食的制作有古远的历史,而月饼的前身是汉代以来的胡饼。关于中秋月饼产生于唐代和宋代的说法都是没有确凿依据的。有充分资料证明,作为中秋节节令食品的月饼正式出现于明代,开始它是拜月的供品,后来才演变为节令食品。 展开更多
关键词 中秋节 月饼 胡饼 渊源 MOON Cake(月饼) HU Cake(胡饼)
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