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21.
试用暗物质理论解释惯性和惯性力的物理机制(上)   总被引:1,自引:1,他引:0  
基于对暗物质的多年探讨,我们认为宇宙空间是具有质量、相对均匀、连续稳定和有相当弹性暗物质群体(DMG)的空间.自然、宇宙万物终生处于群体引力制约之中,它们因此也获得了相应的惯性.本文立足于上述的宇宙空间,借助宇宙学原理、马赫原理和爱因斯坦等效原理,提出了物质客体的惯性机制和被称为虚力的惯性力机制 同时本文也解读所有惯...  相似文献   
22.
依托2012—2015年福建空管分局进近情况及福州长乐国际机场航班延误情况,由专家及一线管制员为各因素不同延误等级所占比重进行打分,建立延误等级模型,再通过打分情况建立物元评估模型,得出关联隶属度评估机场综合延误程度,以及使用临时航线前后延误程度的变化,最后,得到了福州长乐机场延误影响因素及综合延误程度的定性定量分析结果。  相似文献   
23.
In this review I first describe the nature of the three kinds of High-Mass X-ray Binaries (HMXBs), accreting through: (i) Be circumstellar disc, (ii) supergiant stellar wind, and (iii) Roche lobe filling supergiants.  相似文献   
24.
Observation of Mars shows signs of a past Earth-like climate, and, in that case, there is no objection to the possible development of life, in the underground or at the surface, as in the terrestrial primitive biosphere. Sample analysis at Mars (SAM) is an experiment which may be proposed for atmospheric, ground and underground in situ measurements. One of its goals is to bring direct or indirect information on the possibility for life to have developed on Mars, and to detect traces of past or present biological activity. With this aim, it focuses on the detection of organic molecules: volatile organics are extracted from the sample by simple heating, whereas refractory molecules are made analyzable (i.e. volatile), using derivatization technique or fragmentation by pyrolysis. Gaseous mixtures thus obtained are analyzed by gas chromatography associated to mass spectrometry. Beyond organics, carbonates and other salts are associated to the dense and moist atmosphere necessary to the development of life, and might have formed and accumulated in some places on Mars. They represent another target for SAM. Heating of the samples allows the analysis of structural gases of these minerals (CO2 from carbonates, etc.), enabling to identify them. We also show, in this paper, that it may be possible to discriminate between abiotic minerals, and minerals (shells, etc.) created by living organisms.  相似文献   
25.
可凝性气体对低温光学元件表面污染的测试设备   总被引:3,自引:0,他引:3  
详细介绍了某些可凝性气体对低温光学元件表面污染测试设备的基本原理,基本结构及使用方法;对其主要性能进行了实验测定,并给出了系统误差分析,该设备结构简单,功能齐全,性能可靠,使用方便;测试波段从近红外直至远红外,精度优于3%,与国外同类仪器相当,可用于各类可凝性气冷凝霜层的测试研究,为进一步发展空间技术提供了有效的研究设备。  相似文献   
26.
27.
Cool objects glow in the infrared. The gas and solid-state species that escape the stellar gravitational attraction of evolved late-type stars in the form of a stellar wind are cool, with temperatures typically ?1500 K, and can be ideally studied in the infrared. These stellar winds create huge extended circumstellar envelopes with extents approaching 10191019 cm. In these envelopes, a complex kinematical, thermodynamical and chemical interplay determines the global and local structural parameters. Unraveling the wind acceleration mechanisms and deriving the complicated structure of the envelopes is important to understand the late stages of evolution of ∼97% of stars in galaxies as our own Milky Way. That way, we can also assess the significant chemical enrichment of the interstellar medium by the mass loss of these evolved stars. The Herschel Space Observatory is uniquely placed to study evolved stars thanks to the excellent capabilities of the three infrared and sub-millimeter instruments on board: PACS, SPIRE and HIFI. In this review, I give an overview of a few important results obtained during the first two years of Herschel observations in the field of evolved low and intermediate mass stars, and I will show how the Herschel observations can solve some historical questions on these late stages of stellar evolution, but also add some new ones.  相似文献   
28.
用于深层充电评估的卫星介质电导率测量技术研究   总被引:1,自引:1,他引:0  
准确测量得到卫星介质材料的电导率对于卫星深层充电危害评估具有重要意义。在电荷贮存衰减法的基础上,文章提出了一种获得介质材料暗电导率和辐射诱导电导率的试验测量和数值计算方法,即采用90Sr-90Y β放射源,在温度为20 ℃、束流密度为5 pA/cm2的条件下对卫星常用的聚酰亚胺材料进行辐照试验,通过测得的材料表面电位随时间的变化曲线,拟合得到材料的暗电导率和辐射诱导电导率。该方法已在某卫星产品的充电评估中得到应用,计算结果与模拟试验结果符合较好。  相似文献   
29.
The Dark Matter Particle Explorer (DAMPE) mission is one of the five scientific space science missions within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Science (CAS) approved in 2011. The main scientific objective of DAMPE is to detect electrons and photons in the range of 5GeV-10TeV with unprecedented energy resolution (1.5% at 100GeV) in order to identify possible Dark Matter (DM) signatures. It will also measure the flux of nuclei up to above 500TeV with excellent energy resolution (40% at 800GeV), which will bring new insights to the origin and propagation high energy cosmic rays. With its excellent photon detection capability, the DAMPE mission is well placed for new discoveries in high energy-ray astronomy as well.   相似文献   
30.
In this paper, we give a review of direct detection searches reported by the DAMA (China as a Co-I), and indirect detection searches reported by the ATIC (China as a Co-I). We also outline the future plans of dark matter search in China.   相似文献   
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