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841.
New methods of local helioseismology and uninterrupted time series of solar oscillation data from the Solar and Heliospheric
Observatory (SOHO) have led to a major advance in our understanding of the structure and dynamics of active regions in the
subsurface layers. The initial results show that large active regions are formed by repeated magnetic flux emergence from
the deep interior, and that their roots are at least 50 Mm deep. The active regions change the temperature structure and flow
dynamics of the upper convection zone, forming large circulation cells of converging flows. The helioseismic observations
also indicate that the processes of magnetic energy release, flares and coronal mass ejections, might be associated with strong
(1–2 km/s) shearing flows, 4–6 Mm below the surface. 相似文献
842.
L.H. Deng Z.Q. Qu T. Liu W.J. Huang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
We investigate the north–south (N–S) asynchrony of the polar faculae and compare it with the hemispheric asynchrony of solar activity at low latitudes. We find that, (1) both the solar activity at high and low latitudes do not synchronously occur in the northern and southern hemispheres, there is phase shifts between the two hemispheres; (2) the N–S asynchrony of the polar faculae is a function of latitudes, implying that the asynchrony of the polar faculae between the two hemispheres is related to the hemispheric asymmetry and latitudinal distribution of the polar faculae. 相似文献
843.
M. Kruglanski M. De Mazire A.C. Vandaele D. Hurtmans 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,37(12):2160-II
A non-empirical algorithm is presented to retrieve the optical depth in the 750–1250 cm−1 spectral range, of aerosol located in the boundary layer over the ocean, from nadir high-resolution radiance spectra in the thermal infrared. The algorithm is based on a line-by-line radiative transfer forward model and used the Optimal Estimation Method for the retrieval. Its performance strongly depends on the quality of the a priori temperature and H2O atmospheric profiles. To demonstrate the relevance of the algorithm, distributions of maritime aerosol parameters have been retrieved from IMG/ADEOS data for December 1996, using the algorithm with the LBLRTM radiative transfer code, and ERA40 (ECMWF) a priori atmospheric profiles and surface conditions. 相似文献
844.
Jorge Casares Phil Charles 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2731-2736
The determination of fundamental parameters in X-ray luminous (persistent) X-ray binaries has been classically hampered by the large optical luminosity of the accretion disc. New methods, based on irradiation of the donor star and burst oscillations, provide the opportunity to derive dynamical information and mass constraints in many persistent systems for the first time. These techniques are here reviewed and the latest results presented. 相似文献
845.
Jean-Marie Hameury Jean-Pierre Lasota 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2857-2861
Outer radius variations play an important role in the disc structure and evolution. We consider theoretical and observational consequences of such variations in cataclysmic binaries and low-mass X-ray binaries. We find that the action of tidal torques must be important well inside the tidal radius. We also conclude that it is doubtful that the tidal–thermal instability is responsible for the superoutburst/superhump phenomena. 相似文献
846.
用SIMOX(Separationby Implanted Oxygen,即氧注入隔离)技术制备SOI-CMOS用的SOI(Silicon OnInsu lator,即绝缘体上长单晶硅膜)样品;对SOI样品红外吸收光谱的分析,从而计算了SOI结构材料中SiO2埋层的厚度;测试样品不同点的红外吸收光谱,可考察样品SiO2埋层厚度的不均匀性,据此,并可分析与之相关的SOI样品的质量参数.这种分析方法,是一种无损的检测手段,具有实用价值. 相似文献
847.
S. Karakula W. Tkaczyk F. Giovannelli 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
In the spherical accretion onto massive objects, the matter may be heated up to temperatures as high as 1012 °K. In such a hot plasma, the thermal bremsstrahlung (e-e and e-p) and π° decay from inelastic collisions of protons are the main γ-ray sources. We determined the γ -ray production spectra from the π° decay and from bremsstrahlung for different temperatures. The expected γ-ray spectra were evaluated too in order to fit experimental data. We have fitted COS B data from 3C 273 using a two temperatures plasma model. The best fit is for
(M8 is the black hole mass in 108 M) which gives
. The hard X-ray measurements do not contradict the bremsstrahlung spectrum. 相似文献
Full-size image (1K)
848.
提供两种方法,确定结构刚度指标。第一种方法是已知刚度变差系数Cf,确定结构刚度指标。第二种方法是借助卡埃分布表,确定结构刚度指标。这两种方法都能得到满意的结果。文中还列举了许多实例,并指出了需要注意的问题。 相似文献
849.
研制出一种在晶化激光功率为4mW时晶化时间为180ns的可逆相变型光纪录介质。其擦写循环次数可达10~6次。分析了其快速晶化机理。 相似文献
850.
本文通过在硅衬底上用MOCVD方法生长的砷化镓外延薄膜的变激发强度的近红外光致发光,研究了在液氮温度下峰值为1.13与1.04eV两个发光带的发光特性。 相似文献