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How the Flat Space Cosmology Model Correlates the Recombination CMB Temperature of 3000 K with a Redshift of 1100
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作者 Eugene Terry Tatum U. V. S. Seshavatharam 《Journal of Modern Physics》 2024年第2期174-178,共5页
This paper shows how the Flat Space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is given in support of the recent publication that the... This paper shows how the Flat Space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is given in support of the recent publication that the Tatum and Seshavatharam Hubble temperature formulae can be derived using the Stephan-Boltzmann dispersion law. Thus, as explained herein, the era of high precision Planck scale quantum cosmology has arrived. 展开更多
关键词 Hubble Constant cosmic Microwave Background Quantum Cosmology Stephan-Boltzmann Upsilon Coupling Constant Flat space Cosmology ΛCDM Cosmology
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Pinched Material Einstein Space-Time Produces Accelerated Cosmic Expansion
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作者 M. S. El Naschie 《International Journal of Astronomy and Astrophysics》 2014年第1期80-90,共11页
An instructive analogy between the deformation of a pinched elastic cylindrical shell and the anti-gravity behind accelerated cosmic expansion is established. Subsequently the entire model is interpreted in terms of a... An instructive analogy between the deformation of a pinched elastic cylindrical shell and the anti-gravity behind accelerated cosmic expansion is established. Subsequently the entire model is interpreted in terms of a hyperbolic fractal Rindler space-time leading to the same robust results regarding real energy and dark energy being 4.5% and 95.5% respectively in full agreement with all recent cosmological measurements. 展开更多
关键词 Dark Energy Rindler space-TIME CARTAN Torsion Pinched Elastic Shells Negative Gravity cosmic ACCELERATED EXPANSION Fractal space-TIME Topological Defects Hardy’s Quantum Entanglement Hawking’s Radiation COSSERAT Elasticity
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A Quantum Space Model of Cosmic Evolution: Dark Energy and the Cyclic Universe
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作者 Carlos A. Melendres 《Journal of Modern Physics》 CAS 2022年第11期1305-1313,共9页
We present a Quantum Space Model (QSM) of cosmic evolution based on the theory that space consists of energy quanta from which our universe came about. We used the Friedmann equations to trace its history and predict ... We present a Quantum Space Model (QSM) of cosmic evolution based on the theory that space consists of energy quanta from which our universe came about. We used the Friedmann equations to trace its history and predict its ultimate fate. Results provide further support to our recent proposal that the accelerating expansion of the universe is due to a scalar space field which has become known as Dark Energy. In our model, the universe started from high energy space quanta which were triggered by quantum fluctuations that caused the Big Bang. It then expanded and cooled undergoing phase transitions to radiation, fundamental particles, and matter. Matter agglomerated and grew into stars, galaxies, etc. and was eventually consolidated by gravity into Black Holes, which finally ended in a Big Crunch in a state of deep freeze inside the Black hole at 1.380 trillion years. Fluctuations, quantum tunneling, or some other mechanisms caused a new Bang to start another cycle in its life. Our results are in good agreement with the theoretical predictions of a cyclic universe by Steinhardt and his associates, and by Penrose. Space and energy are equivalent as embodied in the Planck energy equation. They give rise to the two principal long range forces in the universe: the gravitational force and the space force. The latter may be the fifth force in the universe. The two forces could provide the clockwork mechanism operating our cyclic universe. If the Law of Conservation of Energy is universal, then the cosmos is eternal. 展开更多
关键词 Quantum space Model spaceons Dark Energy Gravitational Waves cosmic Evolution Expansion of the Universe Black Holes Big Bang Big Crunch Cyclic Universe
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仿紧局部cosmic空间的CL-映象 被引量:1
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作者 谷建胜 《苏州科技学院学报(自然科学版)》 CAS 2004年第4期28-30,共3页
建立了仿紧局部cosmic空间的几类序列覆盖CL-映象的特征。
关键词 仿紧空间 局部cosmic空间 序列覆盖映射 序列商映射 CL-映射
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人法地,地法天,天法道,道法自然——中国风景园林中的师法自然观
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作者 李金路 欧阳高奇 《中国园林》 CSCD 北大核心 2024年第8期12-17,共6页
中国风景园林充分反映了中华民族的师法自然观。中国传统文化中的人、山水、地、天、道、元气、宇宙诸多概念表达出多维度的自然;“人法地,地法天,天法道,道法自然”,系统论述从人到自然之间诸多层次的师法关系。中国风景园林则在从人... 中国风景园林充分反映了中华民族的师法自然观。中国传统文化中的人、山水、地、天、道、元气、宇宙诸多概念表达出多维度的自然;“人法地,地法天,天法道,道法自然”,系统论述从人到自然之间诸多层次的师法关系。中国风景园林则在从人到自然的多层次关系中,通过自然崇拜、君子比德、模山范水、人做天开、宇宙浓缩等诸多形式最终落脚到师法自然,这就使得中国风景园林形成了“外师造化、内得心源”的认识方法、“虽由人作,宛自天开”的价值取向、阴阳和谐山水格局的空间营造手法,以及自然而然的宇宙再现。中国风景园林能艺术地凝练出有形自然、无形自然、万物演化规律的自然和体现宇宙法则的自然,师法自然观在其衍化过程中留下了深深的痕迹。 展开更多
关键词 风景园林 师法自然 宇宙时空 阴阳
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Applying the Stefan-Boltzmann Law to a Cosmological Model (a Brief Note)
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第11期1717-1722,共6页
This brief note brings the reader up-to-date with the recent successes of the new Haug-Tatum cosmology model. In particular, the significance of recent proof that the Stefan-Boltzmann law applies to such a model is em... This brief note brings the reader up-to-date with the recent successes of the new Haug-Tatum cosmology model. In particular, the significance of recent proof that the Stefan-Boltzmann law applies to such a model is emphasized and a rationale for this is given. Remarkably, the proposed solutions of this model have incorporated all 580 supernova redshifts in the Union2 database. Therefore, one can usefully apply this thermodynamic law in the form of a continually expanding black-body universe model. To our knowledge, no other cosmological model has achieved such high-precision observational correlation. 展开更多
关键词 Haug-Tatum Cosmology Stefan-Boltzmann Law Flat space Cosmology CMB cosmic Thermodynamics Rh = ct Cosmology Model Black Body
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COSMIC反演精度和有关特性的检验 被引量:22
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作者 杜明斌 杨引明 丁金才 《应用气象学报》 CSCD 北大核心 2009年第5期586-593,共8页
COSMIC是一个由6颗低轨卫星组成的用于天气、气候和电离层观测的空基GPS星座观测系统,从2006年9月开始每天可提供覆盖全球的约2000-3000个掩星点,掩星过程可提供从40 km高空到近地面的大气温、压、湿的廓线资料。为了有效利用这些资料,... COSMIC是一个由6颗低轨卫星组成的用于天气、气候和电离层观测的空基GPS星座观测系统,从2006年9月开始每天可提供覆盖全球的约2000-3000个掩星点,掩星过程可提供从40 km高空到近地面的大气温、压、湿的廓线资料。为了有效利用这些资料,以探空资料为基准,对2007年1—10月我国及邻近区域的COSMIC掩星资料进行精度、可用性和全天候性的检验。结果表明:COSMIC反演的温度和折射率的精度很高,水汽压的精度相对较差。与NCEP/NCAR再分析资料相比,折射率和湿度廓线有更高精度。 展开更多
关键词 空基GPS气象学 COMIC掩星 飞机下投探空仪
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Cosmic Time Transformations in Cosmological Relativity 被引量:1
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作者 Firmin J. Oliveira 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第2期253-279,共27页
The relativity of cosmic time is developed within the framework of Cosmological Relativity in five dimensions of space, time and velocity. A general linearized metric element is defined to have the form , where the co... The relativity of cosmic time is developed within the framework of Cosmological Relativity in five dimensions of space, time and velocity. A general linearized metric element is defined to have the form , where the coordinates are time , radial distance for spatials x, y and z, and velocity v, with c the speed of light in vacuum and t the Hubble-Carmeli time constant. The metric is accurate to first order in and v/c . The fields and are general functions of the coordinates. By showing that =, a metric of the form is obtained from the general metric, implying that the universe is flat. For cosmological redshift z, the luminosity distance relation is used to fit combined distance moduli from Type 1a supernovae up to z is obtained for the matter density parameter at the present epoch. Assuming a baryon density of , a rest mass energy of (9.79+ 0.47) GeV is predicted for the anti-baryonic and the particles which decay from a hypothetical particle. The cosmic aging function makes good fits to light curve data from two reports of Type 1a supernovae and in fitting to simulated quasar like light curve power spectra separated by redshift . We determine the multipole of the first acoustic peak of the Cosmic Microwave Background radiation anisotropy to be and a sound horizon of on today’s sky. 展开更多
关键词 Flat space cosmic Time Time Dilation Dark Matter
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On the Relationship between Meteorological Variables, Dst Index, Solar Wind Speed, Solar Radio Flux, and Cosmic Rays and COVID-19 Cases
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作者 Maghrabi Abdullrahman 《Atmospheric and Climate Sciences》 CAS 2022年第3期517-531,共15页
This study aims to determine the influential role of the meteorological, solar, and geophysical factors and cosmic rays on the transmission of COVID-19 in Riyadh, Saudi Arabia. The meteorological factors were air temp... This study aims to determine the influential role of the meteorological, solar, and geophysical factors and cosmic rays on the transmission of COVID-19 in Riyadh, Saudi Arabia. The meteorological factors were air temperature, relative humidity, wind speed, and atmospheric pressure. The solar radio flux, Dst index, and solar wind speed were utilized as representatives of the solar and geophysical variables. The association between these variables and the COVID-19 pandemic cases from 3 April 2020 to 1 August 2021 was investigated using the Spearman and Kendall rank correlation tests. The obtained results showed that the air temperature and average wind speed are positively associated with the daily number of reported COVID-19 cases. On the other hand, the mean values of relative humidity and atmospheric pressure are inversely correlated with the number of COVID-19 cases in Riyadh. Moreover, the results showed that the Dst index and cosmic rays are positively correlated with the COVID-19 cases. Contrarily, solar wind speed and radio flux at 10.7 cm have negative correlations with the COVID-19 cases. The obtained results will help the epidemiologists to understand the behavior of the virus against meteorological, solar, and geophysical variables and can be considered as a useful supplement to help national and international organizations and healthcare policymakers in the process of strategizing to combat COVID-19. 展开更多
关键词 COVID-19 Solar Activity METEOROLOGY space Weather cosmic Rays
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地月空间粒子辐射环境及其对月表物质的影响研究进展 被引量:1
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作者 史全岐 张江 +8 位作者 乐超 宗秋刚 谢良海 王慧姿 韩晨尧 傅越 商文赛 郭瑞龙 田安民 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2023年第7期2685-2702,共18页
由于没有全球磁场和稠密大气保护,月球直接受宇宙线、太阳风和地球风粒子的轰击.了解月球空间粒子辐射的特性、粒子的来源和传输等过程,本身是亟待解决的空间科学基础问题,同时还可帮助更好地提供预报和预警,为保障探月和载人登月等活... 由于没有全球磁场和稠密大气保护,月球直接受宇宙线、太阳风和地球风粒子的轰击.了解月球空间粒子辐射的特性、粒子的来源和传输等过程,本身是亟待解决的空间科学基础问题,同时还可帮助更好地提供预报和预警,为保障探月和载人登月等活动的安全提供理论参考;此外,月球空间辐射环境中的粒子与月表作用产生的水等物质对载人登月和月球基地意义重大,且月表物质保存了空间环境较为完整的信息和演化历史,对研究地月系统及太阳系其他天体(乃至系外行星)的宜居性与演化,也具有重要的科学价值.本文在简要总结地月空间粒子辐射环境研究现状的基础上,重点分析了近月粒子辐射环境及其对月表物质所产生的影响,梳理了宇宙线、太阳能量粒子事件、太阳风、地球风以及月源粒子等不同辐射的来源和传输机制,这些粒子与月表作用产生水、赤铁矿、中性原子等物质的过程,以及相关过程对月球空间环境的影响、对地月系统演化的启示等关键科学问题,并提出了解决问题所面临的技术难点,最后对未来可能的重点研究内容进行了展望,可为后续月球探测任务(例如嫦娥四期和国际月球科研站等)相关领域科技规划提供一定的参考. 展开更多
关键词 地月空间环境 空间粒子辐射 宇宙线 太阳风 太阳能量粒子 地球风 月表物质 月球水
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Calculating Radiation Temperature Anisotropy in Flat Space Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2018年第10期1946-1953,共8页
The purpose of this paper is to show how one can use the FSC model of gravitational entropy to calculate cosmic radiation temperature anisotropy for any past cosmic time t since the Planck scale. Cosmic entropy follow... The purpose of this paper is to show how one can use the FSC model of gravitational entropy to calculate cosmic radiation temperature anisotropy for any past cosmic time t since the Planck scale. Cosmic entropy follows the Bekenstein-Hawking definition, although in the correct-scaling form of, which scales 60.63 logs of 10 from the Planck scale. In the FSC model, cosmic radiation temperature anisotropy At = (t/to). The derived past anisotropy value can be compared to current co-moving anisotropy defined as unity (to/to). Calculated in this way, current gravitational entropy and temperature anisotropy have maximum values, and the earliest universe has the lowest entropy and temperature anisotropy values. This approach comports with the second law of thermodynamics and the theoretical basis of the Sachs-Wolfe effect, gravitational entropy as defined by Roger Penrose, and Erik Verlinde’s “emergent gravity” theory. 展开更多
关键词 FLAT space COSMOLOGY cosmic Microwave Background CMB ANISOTROPY COSMOLOGY Theory cosmic ENTROPY Gravitational ENTROPY Black Holes Standard COSMOLOGY
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The Basics of Flat Space Cosmology
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作者 Eugene Terry Tatum U. V. S. Seshavatharam S. Lakshminarayana 《International Journal of Astronomy and Astrophysics》 2015年第2期116-124,共9页
We present a new model of cosmology which appears to show great promise. Our flat space cosmology model, using only four basic and reasonable assumptions, derives highly accurate Hubble parameter H0, Hubble radius R0 ... We present a new model of cosmology which appears to show great promise. Our flat space cosmology model, using only four basic and reasonable assumptions, derives highly accurate Hubble parameter H0, Hubble radius R0 and total mass M0 values for our observable universe. Our model derives a current Hubble parameter of , in excellent agreement with the newly reported (lower limit) results of the 2015 Planck Survey. Remarkably, all of these derivations can be made with only these basic assumptions and the current CMB radiation temperature . The thermodynamic equations we have generated follow Hawking’s black hole temperature formula. We have also derived a variety of other useful cosmological formulae. These include angular velocity and other rotational formulae. A particularly useful hyperbolic equation, , has been derived, which appears to be an excellent fit for the Planck scale as well as the current observable universe scale. Using the flat space Minkowski relativistic formula for Doppler effect, and a formula for staging our cosmological model according to its average mass-energy density at every Hubble time (universal age) in its expansion, a persuasive argument can be made that the observable phenomena attributed to dark energy are actually manifestations of Doppler and gravitational redshift. Finally, a theory of cosmic inflation becomes completely unnecessary because our flat space cosmology model is always at critical density. 展开更多
关键词 FLAT space COSMOLOGY cosmic Inflation Dark Energy Hubble Parameter Critical Density Angular Velocity LIGHT SPEED Expansion LIGHT SPEED Rotation Redshift Universe CMBR
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How a Realistic Linear <i>R<sub>h</sub>= ct </i>Model of Cosmology Could Present the Illusion of Late Cosmic Acceleration
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作者 Eugene Terry Tatum U. V. S. Seshavatharam 《Journal of Modern Physics》 2018年第7期1397-1403,共7页
Realistic FLRW cosmic coasting models which contain matter now appear to be a reasonable alternative in explaining the accumulated Supernova Cosmology Project data since 1998. In sharp contrast to the unrealistic orig... Realistic FLRW cosmic coasting models which contain matter now appear to be a reasonable alternative in explaining the accumulated Supernova Cosmology Project data since 1998. In sharp contrast to the unrealistic original classic Milne universe, which was entirely devoid of matter, these modified Milne-type models containing matter, often referred to as realistic linear Rh = ct models, have rapidly become the primary competition with standard cosmology. This paper compares the expected relative luminosity distances and relative angular diameter distances for given magnitudes of redshift within these two competing models. A simple ratio formula is derived, which explains how expected luminosity distances and angular diameter distances for given magnitudes of redshift within a realistic Milne-type cosmic expansion could create the illusion (for standard model proponents) of cosmic acceleration where none exists. 展开更多
关键词 Dark Energy Survey COSMOLOGY Theory cosmic COASTING cosmic Flatness Type Ia Supernovae CMBR Flat space COSMOLOGY MILNE Universe Theories
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Predicted Dark Matter Quantitation in Flat Space Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2018年第8期1559-1563,共5页
The purpose of this paper is to show how the dark matter predictions of FSC differ with respect to the standard cosmology assertion of a universal dark matter-to-visible matter ratio of approximately 5.3-to-1. FSC pre... The purpose of this paper is to show how the dark matter predictions of FSC differ with respect to the standard cosmology assertion of a universal dark matter-to-visible matter ratio of approximately 5.3-to-1. FSC predicts the correct ratio to be approximately 9-to-1, based primarily on the universal observations of global spatial flatness in the context of general relativity. The FSC Friedmann equations incorporating a Lambda?&Lambda;?cosmological term clearly indicate that a spatially flat universe must have equality of the positive curvature (matter mass-energy) and negative curvature (dark energy) density components. Thus, FSC predicts that observations of the Milky Way and the nearly co-moving galaxies within 100 million light years will prove the 5.3-to-1 ratio to be incorrect. The most recent galactic and perigalactic observations indicate a range of dark matter-to-visible matter ratios varying from essentially zero (NGC 1052-DF2) to approximately 23-to-1 (Milky Way). The latter ratio is simply astonishing and promises an exciting next few years for astrophysicists and cosmologists. Within the next few years, the mining of huge data bases (especially the Gaia catalogue and Hubble data) will resolve whether standard cosmology will need to change its current claims for the cosmic energy density partition to be more in line with FSC, or whether FSC is falsified. A prediction is that standard cosmology must eventually realize the necessity of resolving the tension between their flatness observations and their assertion of dark energy dominance. The author makes the further prediction that FSC will soon become the new paradigm in cosmology. 展开更多
关键词 FLAT space COSMOLOGY Standard COSMOLOGY COSMOLOGY Theory Dark Matter cosmic Microwave Background PLANCK Collaboration GRAVITATIONAL Entropy Black Holes
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Cosmic Time as an Emergent Property of Cosmic Thermodynamics
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作者 Eugene Terry Tatum U. V. S. Seshavatharam 《Journal of Modern Physics》 2018年第10期1941-1945,共5页
This paper, in conjunction with recent Flat Space Cosmology (FSC) publications, provides theoretical support for cosmic time being an emergent property of cosmic entropy and temperature. Therefore, if Verlinde’s “em... This paper, in conjunction with recent Flat Space Cosmology (FSC) publications, provides theoretical support for cosmic time being an emergent property of cosmic entropy and temperature. Therefore, if Verlinde’s “emergent gravity” theory is correct, both time and gravity are most fundamentally emergent properties of cosmic thermodynamics. Since emergent properties within complex systems with a huge number of degrees of freedom are often not definable at the smallest scales, these results suggest that quantum time and quantum gravity may be no more definable than consciousness within two connecting neurons. String theorists now struggling to define quantum space-time and quantum gravity should bear this in mind. 展开更多
关键词 Flat space COSMOLOGY COSMOLOGY Theory Emergent Gravity DARK Matter cosmic Entropy Entropic ARROW of TIME Universal Temperature Black HOLES
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基于暗物质粒子探测卫星的宇宙线直接探测研究
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作者 袁强 《天文学报》 CAS CSCD 北大核心 2023年第5期1-9,共9页
高能宇宙线的起源、加速和传播是重大的前沿科学问题,回答该问题需要对宇宙线的能谱、各向异性以及各类高能天体电磁辐射进行精确观测.通过空间粒子探测器对宇宙线各成分能谱的直接测量是研究宇宙线物理问题的重要手段.中国于2015年底... 高能宇宙线的起源、加速和传播是重大的前沿科学问题,回答该问题需要对宇宙线的能谱、各向异性以及各类高能天体电磁辐射进行精确观测.通过空间粒子探测器对宇宙线各成分能谱的直接测量是研究宇宙线物理问题的重要手段.中国于2015年底发射并持续运行至今的暗物质粒子探测卫星以其大接受度、高能量分辨率等特点,在宇宙线直接探测方面取得了系列重要成果,揭示出质子、氦核、硼碳和硼氧比例等宇宙线能谱的新结构,为理解宇宙线起源等科学问题提供了新的依据.介绍了暗物质粒子探测卫星的仪器设置、运行状况、科学成果及其物理意义. 展开更多
关键词 空间天文 宇宙线 辐射机制:非热 粒子天体物理
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空间辐射对空间站航天员的剂量影响分析
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作者 吴康 方美华 +5 位作者 张昭 周宏涛 陈建飞 梁筝 王彪 宋定一 《航天器环境工程》 CSCD 北大核心 2023年第5期475-483,共9页
为有效实施对航天员的空间辐射防护,采用计算机断层扫描数据(CT)建立了精细化男性体素模型;基于Geant4建立蒙特卡罗程序计算空间站轨道辐射经过舱壁(5 g·cm^(-2)等效铝屏蔽)后在体模中的辐射剂量;分析了不同辐射粒子在体素模型组... 为有效实施对航天员的空间辐射防护,采用计算机断层扫描数据(CT)建立了精细化男性体素模型;基于Geant4建立蒙特卡罗程序计算空间站轨道辐射经过舱壁(5 g·cm^(-2)等效铝屏蔽)后在体模中的辐射剂量;分析了不同辐射粒子在体素模型组织或器官中的吸收剂量、当量剂量和有效剂量。计算结果表明:航天员体内吸收剂量大约80%来源于地球辐射带(ERB)质子;大约14%来源于银河宇宙线(GCR)质子;α粒子的剂量贡献占比约为5%;其余重离子的剂量贡献占比在1%左右。另外,航天员吸收的当量剂量和有效剂量50%左右来自于ERB质子,另50%左右来自于GCR粒子。计算结果将有助于评估航天员在空间站舱内的潜在辐射风险并提供辐射防护参考。 展开更多
关键词 空间站 航天员 辐射防护 地球辐射带 银河宇宙线 辐射剂量 Geant4软件
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空间碎片与空间环境 被引量:49
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作者 李春来 欧阳自远 都亨 《第四纪研究》 CAS CSCD 北大核心 2002年第6期540-551,共12页
空间碎片起源于人类的航天活动 ,目前空间碎片的空间密度已经对航天器的安全造成威胁 ,且其数量仍在高速增长 ,已成为一个引人瞩目的环境问题 ,航天器受空间碎片撞击的事件时有发生。大空间碎片的撞击会使航天器姿态和轨道发生改变 ,更... 空间碎片起源于人类的航天活动 ,目前空间碎片的空间密度已经对航天器的安全造成威胁 ,且其数量仍在高速增长 ,已成为一个引人瞩目的环境问题 ,航天器受空间碎片撞击的事件时有发生。大空间碎片的撞击会使航天器姿态和轨道发生改变 ,更严重的是会导致航天器破损甚至完全解体 ;小空间碎片的撞击会使航天器表面性能改变 ,部分器件损伤或失效 ,使航天器丧失功能。目前地基设备只能对厘米级及更大的碎片进行观测、跟踪和编目 ,航天器可以根据空间碎片的轨道参数进行规避和机动飞行 ,以避免撞毁 ;小空间碎片 (<1cm)数量众多 ,但无法进行轨道测量 ,只能通过天基直接探测和样品回收获得数据 ,数值建模和超高速撞击模拟实验是进行小空间碎片风险评估和撞击效应研究的有效方法。对小空间碎片只能采取被动防护的方法 ,在航天器总体设计、防护结构和材料方面着手 ,降低空间碎片的威胁。改善空间环境 ,减少空间碎片的最根本方法是对航天器采取钝化措施 ,减少空间碎片的产生 ,理论上还可以采取措施 ,清扫、清除或回收空间碎片。 展开更多
关键词 空间碎片 宇宙尘 空间环境 撞击 航天器 航天活动
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在生物堆试验中用塑料核径迹探测器作高游离宇宙线重核的辐射生物学研究 被引量:14
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作者 黄荣庆 蒋兴村 +3 位作者 李金国 刘宗贤 顾瑞琦 李群 《核技术》 CAS CSCD 北大核心 1991年第7期428-429,共2页
本文报道1988年8月首次在中国返回型卫星舱内放置的两个封闭生物堆试验中应用塑料核径迹探测器跟踪定位测量高游离宇宙线重核粒子对植物的辐射损伤情况。在空间诱变育种研究方面得到了令人满意的初步结果。
关键词 宇宙线 生物堆 径迹探测器
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仿紧局部cosm ic空间的一些性质 被引量:4
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作者 李进金 《数学研究》 CSCD 2000年第3期340-344,共5页
给出仿紧局部 cosmic空间的一个特征 ;建立了仿紧局部 cosmic空间的几类序列覆盖L映象的特征 ;证明了闭 L映射和商 ss映射保持仿紧局部 cosmic空间的性质 .此外 ,还给出仿紧局部 cosmic空间的一些映射性质 .
关键词 仿紧空间 局部cosmic空间 序列覆盖映射 商映射 闭L映射 SS映射
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