The clustering properties of Luminous Red Galaxies     

X.F. Deng  S.Y. Zou  J.Z. He  P. Jiang  X.X. Tang  X.X. Qian 《Astronomische Nachrichten》2008,329(1):69-76

By cluster analysis, we study the clustering properties of Luminous Red Galaxies (LRGs) and compare them with those of Main galaxies. We find that the clustering properties of Luminous Red Galaxies is different from those of Main galaxies, and that LRGs cluster mainly in form of close double and multiple galaxies, galaxy groups. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

Morphological dependence in the spatial orientations of galaxies around the Local Supercluster     

B. Aryal  D. Neupane  W. Saurer 《Astrophysics and Space Science》2008,314(1-3):177-191

We study the spatial orientation of 5 169 galaxies that have radial velocity 3 000 to 5 000 km s⁻¹. The ‘position angle–inclination’ method is used to find the spin vector and the projections of spin vector of the galaxy rotation axes. The spatial isotropic distribution is assumed to examine the non-random effects. For this, we have performed chi-square, Fourier, and auto-correlation tests. We found a random alignment of spin vectors of total galaxies with respect to the equatorial coordinate system. The spin vector projections of total galaxies is found to be oriented tangentially with respect to the equatorial center. The spiral galaxies show a similar orientation as shown by the total sample. Five subsamples of barred spiral (late-type) galaxies show a preferred alignment. However, early-type barred spirals show a random orientation. A weak morphological dependence is noticed in the subsamples of late type barred spirals. A comparison with the previous works and the possible explanation of the results will be presented.  相似文献   

我国摄影测量与遥感发展现状   总被引：1，自引：0，他引：1  

万幼川  刘良明  舒宁 《地理空间信息》2004,2(4):1-3,7

随着摄影测量发展到数字摄影测量阶段及多传感器、多分辨率、多光谱、多时段遥感与其他边缘学科交叉渗透、相互融合,摄影测量与遥感学科已逐渐发展为一门新型的地球空间信息科学。近年来,我国摄影测量与遥感技术表现出许多新的特点,本文分别从十一个方面予以总结。  相似文献   

陕西省恒温层深度主要影响因素及其估算     

周阳  张卉  江星辰  许泽润  王克  穆根胥 《中国地质调查》2019,6(3):81-86

恒温层深度的预测与地热能开发利用、地下空间建设等密切相关,陕西省区域恒温层的研究工作进展较慢。通过探讨恒温层深度的影响因素认为: 导热系数与恒温层深度呈弱负相关; 地表与大气间表面传热系数与恒温层深度呈弱正相关; 大气温度年振幅与恒温层深度呈正相关; 导温系数与恒温层深度呈明显的正相关。介绍并验证了一种土壤恒温层深度的计算方法,通过该方法,计算了全省不同地貌单元恒温层深度的理论值。全省恒温层深度介于10.5~23.8 m之间: 陕北地区恒温层深度为10.5~23.8 m; 关中盆地恒温层深度为11~17.4 m; 陕南地区恒温层深度为11.7~18.6 m。该研究系统地划分了陕西省区域恒温层的深度范围,为陕西省“绿色”追赶超越政策的实施做出贡献。  相似文献   

Statistical microanalysis applied to garnet growth zoning and to cordierite fluid content     

J. PAQUET  F. DELAY  D. LEMAGUER 《Journal of Metamorphic Geology》1989,7(5):529-537

An analytical study to evaluate quantitatively weak zoning of a garnet from a high-grade kinzigite has been performed with an electron microprobe. The technique consists of the reconstruction of a profile step-by-step by successive analyses performed during relatively long counting times (30 s), along a radial profile of 2,500 μm length. The successive analytical data along this profile are statistically treated by Fisher's test and compared with the χ² values (Pearson's law). These statistical tests were applied to assess microprobe stability and analysis homogeneity, and as a consequence to assure high credibility of the radial variations of the garnet. From core to rim, and for each element, zoning appears as the radial juxtaposition of stationary Poissonian samples. These samples being associated, the garnet appears to be constituted of successive concentric domains with stationary compositions. Different substitutions between Mg, Fe, Mn and Ca are evidenced. Such an analytical approach to chemical zoning can be useful for understanding growth mechanisms, and the possible diffusion reactions with the environment at each growth step. In addition, such a procedure can be used to evaluate accurately the fluid content of cordierite, and to appreciate the nature of the fluids concerned. As an example, the fluid content of a cordierite from a similar high-grade kinzigite has been evaluated.  相似文献   

Are many pulsars processed in binary systems?     

A. A. Deshpande  R. Ramachandran  G. Srinivasan 《Journal of Astrophysics and Astronomy》1995,16(1):53-67

A detailed statistical analysis of pulsarcurrent is presented. The conclusions reached are the following: (1) The birthrate of pulsars is about one in 75 ± 15 years. (2) There is evidence forinjection of pulsars into the population of solitary pulsars. Such an injection is particularly pronounced in the magnetic field range 12 < logB < 12.6. (3) This is interpreted as due torecycled pulsars being released into the population. (4) We tentatively conclude that as much as 10 – 15% of all pulsars may have been born and processed in binary systems.  相似文献   

地幔激子热传导机制初步研究     

何安明 《地球科学与环境学报》1990,(2)

本文采用Bose量子统计方法,对地幔矿物的激子热传导问题进行了详细讨论,得到了激子热导率K_(ex)的表达式,并指出在高压和高温下,激活能A对激子热导率的变化速率有重要影响。讨论结果表明,激子热传导作用有可能在下地幔发生,但它却不是热传导的主要机制。  相似文献   

The shape of pebbles     

F. J. Bloore 《Mathematical Geology》1977,9(2):113-122

A theory of pebble erosion is presented, based on the assumption that the rate of erosion at a point on the surface is a function Vof the curvature there. It is proved that for physically reasonable functions V,the sphere is the only shape of pebble which can maintain its proportions as it wears away. An argument is given which leads to a particular form for the function Vand a few qualitative consequences of this form are indicated. The surface of the pebble at time tmay be described using spherical polar coordinates θ, Φ by the radius function r (θ, Φ, t). This function is given by a highly nonlinear partial differential equation. However, in the case of the erosion of a deformed sphere, when terms which are of second order or higher in the deformation are neglected, the equation becomes linear and is a version of the diffusion equation. The stability of the spherical shape against deformations of the various harmonic types is then easily analyzed.  相似文献   

Broken-line and complex frequency distributions     

C. R. Burch  P. N. Murgatroyd 《Mathematical Geology》1971,3(2):135-155

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The Value Of The β Coefficient In The Relaxed Eddy Accumulation Method In Terms Of Fourth-Order Moments     

R. Milne  A. Mennim  K. Hargreaves 《Boundary-Layer Meteorology》2001,101(3):359-373

The commonly measured value of in the relaxed eddy accumulationmethod of about 0.56is shown to arise from the non-Gaussiannature of turbulence. Fourth-orderGram–Charlier functions forthe two-dimensional probability distributionsof variation in the horizontal component of wind velocityand concentrations of water vapour, carbondioxide and methane with respect to thevertical component of wind velocity are used to examinethe value of .An analytical solution for ispresented in terms of fourth-order moments.Under mean conditions, this solution givesa value for of0.557. Variation of is shown to be controlledprimarily by the ratio of the mean ofc'w3 (where c'is relevant to the entity of interest andw' is vertical component of windvelocity) to the correlationcoefficient between the entity concentrationand vertical component of wind velocity.  相似文献