理学 >>> 天文学 >>> 天体化学 >>>
搜索结果: 1-15 共查到知识库 天体化学相关记录60条 . 查询时间(2.193 秒)
The understanding of evolution of solar system has been recently entered a phase of major change with the results of new astronomical observation, several primitive extraterrestrial samples includi...
Uranium concentrations in the rivers of Okinawa Island, Japan were determined in this study. Most rivers in the southwestern area of the island showed high U concentrations, the highest of which was ...
中性氢研究的前沿问题     星际介质  中性氢  结构       2012/9/12
氢元素是宇宙中重子物质的一种主要成分。处于中性状态的原子氢(通常简称为中性氢)在宇宙中分布广泛,是恒星和星系的物质基础。中性氢是分子云中的一种重要成分。它在星系中的分布广泛而延展,是研究星系的物质分布、动力学以及暗物质性质很好的示踪物。中性氢的研究已经有较长的历史,随着射电望远镜灵敏度和角分辨率的提高,正在形成越来越多对中性氢的新认识。对中性氢的进一步研究对其他一些天体物理研究也有重要意义。概括中...
快中子俘获过程(r过程)可以解释大约一半比铁重的稳定(和一些长寿命放射性的)富中子核素的产生,这已经被太阳系及各种金属丰度下恒星的观测结果所证实。为建立r过程模型,需要大量的核物理信息:涉及到β稳定谷与中子滴线之间的各种核素的稳定特性及口衰变分支等物理参数,实验和理论都面临巨大的挑战。综述了近年来贫金属星r过程核合成理论的研究情况,包括人们比较关注的主要C过程与弱r过程核合成、元素丰度分布规律及其...
Using the largest sample of narrow emission line galaxies available so far, we show that their spectral characteristics are correlated with different physical parameters, like the chemical abundances,...
In the excursion set approach to structure formation initially spherical regions of the linear density field collapse if the average density contrast within them exceeds some critical value, \delta_c....
Detailed chemical abundances for twenty one elements are presented for four red giants in the anomalous outer halo globular cluster Palomar 1 ($R_{\rm{GC}} = 17.2$ kpc, $Z=3.6$ kpc) using high-resolut...
Over the past decade a new generation of chemical models have included the dust in the treatment of the ISM. This major accomplishment has been spurred by the growing amounts of data on the highly obs...
In this work we obtain isotropic extensions of the usual spherically symmetric vacuum geometries in general relativity. Exact and perturbative solutions are derived. The classes of geometries obtained...
We present a detailed chemical abundance study of evolved stars in 10 open clusters based on Hydra multi-object echelle spectra obtained with the WIYN 3.5m telescope. From an analysis of both equivale...
Barium stars are moderately rare, chemically peculiar objects, which are believed to be the result of the pollution of an otherwise normal star by material from an evolved companion on the asymptotic ...
We report on a detailed investigation of the gamma-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reporte...
\epsilon Auriga is one of the most mysterious objects on the sky. Prior modeling of its light-curve assumed a dark, inclined, non-transparent or semi-transparent, dusty disk with a central hole. The h...
The chemistry of the early Universe is a fascinating field of study. Even in the absence of any elements heavier than lithium, a surprising degree of chemical complexity proves to be possible, giving ...
Until now, axisymmetric, alpha-disc models have been adopted for calculations of the chemical composition of protoplanetary discs. While this approach is reasonable for many discs, it is not appropria...

中国研究生教育排行榜-

正在加载...

中国学术期刊排行榜-

正在加载...

世界大学科研机构排行榜-

正在加载...

中国大学排行榜-

正在加载...

人 物-

正在加载...

课 件-

正在加载...

视听资料-

正在加载...

研招资料 -

正在加载...

知识要闻-

正在加载...

国际动态-

正在加载...

会议中心-

正在加载...

学术指南-

正在加载...

学术站点-

正在加载...