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151.
以首都圈地区现今活动断层上近20年的位移测量资料为依据,用二维线弹性有限元对该区断层的活动特征进行了拟合,并结合有关资料讨论了该区的地震危险性。结果表明:1977-1986年间该区主压应力优势方位与华北较一致,约为N45°-80°E;1986-1990年其主压应力方向向北偏转,约为N5°-60°E;1990年至现在其主压应力又向东偏转,角度大于第一阶段,约为N80°-95°E。该区的张家口-延庆一带近期有发生中强震的可能;丰镇-阳高-大同地区和凉城-古营盘地区应力较高,也应引起注意。 相似文献
152.
The masers of E-type methanol in orion KL and SGR B2 总被引:2,自引:0,他引:2
Using a simplified model the statistical equilibrium and radiative transfer equations of E-type-CH3OH are solved for Orion KL and SgrB2. According to our calculation results and the observation data taken by Matsakiset al. (1980) and Morimotoet al. (1985a, b), the physical conditions of both sources are estimated. In theJ
2-J
1 E methanol maser region of Orion KL, the density, kinetic temperature, dust temperature, and the fractional abundance are 0.8–2×106 cm–3, 150, 30–90 K, 0.8–8×10–6. In the 4–1-30 E and 5–1-40 E methanol maser region of Sgr B2 the correspondance physical conditions above are 104 cm3, 45, 23 K, and 7×10–7, respectively. 相似文献
153.
154.
155.
提出川滇地洼系“四层楼”铜矿床序列的形成与陆壳演化的成生联系,是与本区陆壳由前地槽—地槽—地台—地洼演化各阶段与之相匹配的成矿作用的产物.与此同时,并总结了本区“四层楼”铜矿床序列的成矿作用具有明显的继承性、新生性、旋回性及层控性四大特点和多因复成矿床的成矿模式. 相似文献
156.
G. Z. Xie F. K. Liu Y. Y. Zhu J. H. Fan R. W. Lu 《Astrophysics and Space Science》1991,179(2):321-329
It has become clear in recent years that relativistic beaming is a good explanation for the BL Lac phenomenon. Of studies based on the relativistic beaming model of BL Lac objects, we note that the orientation of jet's axis to the line-of-sight is very small and, therefore, the observed flux emitted from a rapidly moving source is orders of magnitude higher than the flux in its rest-frame:F
obs = 3 +
F
intr, where is the bulk relativistic Doppler factor. Then the observed apparent magnitudem
v
must be corrected for this effect. For our 39 samples, the corrected apparent magnitudem
v
corr
and logZ have a good correlation. 相似文献
157.
We found that the structure of the Universe can be characterized by a set of actions
s
. This means that some discontinuous phenomena in the Universe can be considered as large-scale quantum effects. The behaviour of matter on a typical scale is determined by the behaviour of matter on other scales through the interactions. 相似文献
158.
Deng Zu-Gan Zhou You-Yuan Liu Yong-Zhen Dai He-Jun 《Astrophysics and Space Science》1986,126(2):301-312
In former works (Zhouet al., 1983, 1985), a quantitative method have been developed to take the selection effects in the identification of emission lines of quasars into account. It was proved that these selection effects may be the cause of the unevenness in the redshift distribution of quasars. The present work is a continuation and development of former works. We use results given by the surveys with same limit-apparent magnitude and choose the quasars whose absolute magnitudes are within a specific range as the analysing samples. Using the method given in the former papers we may find out the evolutionary parameter in an evolutionary law with form of (1+z)
y
from the best fitting between the calculative and observational redshift distribution. The result of analysis shows that the evolutionary law of quasars selected by slitless technique isp =p
0(1 + z)6.5 ± 1 up toz=2.8. This result coincides with and generalizes the earlier result given by other authors. 相似文献
159.
160.
The data such as the H-spectrum-spectroheliographic (SSHG) observations, the H-chromospheric observations, etc., of a flare loop prominence which occurred on the western solar limb on 1981 April 27 have been obtained at Yunnan Observatory. The distribution of the internal motions and the macroscopical motion of the flare loop prominence with time and space in the course of its eruption and ascension is derived from the comprehensive analysis of the data. The possible physical pictures and the instability of the motions of the loop are inferred and discussed. 相似文献