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1.
Experiments on ion implantation were performed in order to better characterize diffusion of noble gases in lunar soil.4He+ at 50 keV with 5×1016 ions/cm2 was implanted into lunar simulants and crystal ilmenite.Helium in the samples was released by stepwise heating experiments.Based on the data,we calculated the helium diffusion coefficient and activation energy.Lunar simulants display similar 4He release patterns in curve shape as lunar soil,but release temperatures are a little lower.This is probably a con... 相似文献
2.
南堡凹陷东营组高精度层序地层格架及沉积体系分析 总被引：1，自引：0，他引：1
在高分辨率三维地震、钻井以及大量地质资料研究基础上,根据层序地层界面特征,将南堡凹陷东营组划分为1个二级层序和4个三级层序。以初始洪泛面和最大洪泛面识别特征为依据,进一步将三级层序划分出体系域。通过层序地层格架特征及其发育位置分析,认为柳南次凹层序地层格架发育的主控因素为构造、物源和湖平面变化。应用层序地层学原理及南堡凹陷沉积充填背景研究,认为柳南次凹的沉积体系类型为冲积扇、扇三角洲、水下扇、重力流及湖泊沉积体系。冲积扇及水下扇体系在低位体系域中发育,高位体系域中扇三角洲体系和重力流发育,湖扩体系域中湖泊体系非常发育。 相似文献
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Zheng Liu Xu-Lin Zhao Fang Huang Xiao-Feng Wang Tian-Meng Zhang Jun-Cheng Chen Tong-Jie Zhang 《天文和天体物理学研究(英文版)》2015,(2):225-236
The optical observations of the type Ic supernova(SN Ic) SN 2012 ap in NGC 1729 are presented. A comparison with other SNe Ic indicates that SN 2012 ap is highly reddened(with E(B- V)host～0.8 mag) and may represent one of the most luminous SNe Ic ever observed, with an absolute V-band peak magnitude of ～-19.3±0.5 mag after extinction correction. The near-maximum-light spectrum shows wide spectral features that are typical of broad-lined SNe Ic. One interesting feature in the spectrum is the appearance of some narrow absorption features that can be attributed to the diffuse interstellar bands, consistent with the large reddening inferred from the photometric method. Based on the light curves and the spectral data, we estimate that SN 2012 ap produced a56 Ni mass of ～ 0.3 ± 0.1M in the explosion, with an ejecta mass of 2.4+0.7-0.7M and a kinetic energy of E5K= 1.1+0.4-0.4× 102 erg. The properties of its progenitor are also briefly discussed. 相似文献
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The statistical mechanics of earthquakes adopts the concepts and methodology of statistical mechanics, especially the theory of critical phenomena, in studying the preparation, initiation, propagation and healing of earthquake rupture, which forms a new branch in the physics of seismic source in recent years. This article introduces to the fundamental concepts of the statistical mechanics of earthquakes. The introduction includes the seismic Hamiltonian, percolation model, earthquake rupture nucleation, and Burridge-Knopoff spring-block model. It is pointed out that some of the statistical mechanical models of earthquakes have a sound seismological basis. There is a smooth "transition" from the "classical" theory to the "modern" theory of seismic source. 相似文献
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STRATIGRAPHY Yao Ling (瑤林) lies 40 li southeast from Chen Hsien city (郴縣), about Long. 112°30′E., Lat. 25°40′N., and is halfway between Chen Hsien city and the well known wolfram mining district, Yao Kang Sien (瑤崗仙). On the 相似文献
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Zhang Jinshan Yu Guohua
Research Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Research Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1995,(3)
- Based on field investigations, this paper analyzes three types of harbour basinns and navigation channel excavated on seabed in Jiaozhou Bay, get a general rule of deposition for excavated trough, it found that pollution is one of crucial factors resulting in the deposition of the excavated trough in the east shore of Jiaozhou Bay. With these results, it predicted the annual deposition thickness for the excavated trough and disclosed the fact that it can't be deposited deadly during one storm. At the same time, with two-dimensional numerical model, it studied the effects of the excavated trough and the reclamation near shore on tidal cureent and said that the excavated trough can decrease the current velocity passing through the trough about 10- 15%, but only limited inside and near the trough and there are no effect on other regions; reclamation can cut off the pollution sources and no obvious effect on the currents of the Jiaozhou Bay. Connecting the deep trough and Cangkou tidal channel with a new 相似文献
10.
Yang Zhengji Zuo Qihua
Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1991,(2)
The wave forces on 1, 2 and 4 vertical circular piles under the action of several wave trains of the same wave parameters, such as Hs,Tp and Mo, but different wave group factor GF are measured in the laboratory. After comparing these forces, it may be concluded that the mean and significant wave forces are almost of no difference for the wave trains with different GF. When GF is larger, the one-tenth of the wave froce extreme is slightly increased and the maximum wave force is much larger than the ones with smaller GF, to which attention must be paid in engineering practice. 相似文献