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991.
Possible triggering of solar activity to big earthquakes (Ms ≥ 8) in faults with near west-east strike in China 总被引:1,自引:0,他引:1
HAN Yanben GUO Zengjian WU Jinbing & MA Lihua . National Astronomical Observatories Chinese Academy of Sciences Beijing China . Earthquake Research Institute of Lanzhou CSB Lanzhou China Correspondence should be addressed to Han Yanben 《中国科学G辑(英文版)》2004,(2)
A big earthquake (Ms = 8.1) occurred at western Kunlun Mts gap on November 14, 2001. It is the biggest earthquake in China in the past 50 years and the only one with a magnitude bigger than 8 in China after Dangxiong Earthquake (M = 8) in Tibet in 1951. The big earthquake has drawn wide attention of scientists in seismological, geophysical, geological and astro-geodynamic circles. Scientists are interested in the occurrence regularity of the very big earthquakes and try to find out the fac… 相似文献
992.
993.
ZHANG Han-hui LIN Zheng-zhong HUANG Chang-cang SUN Rui-qing WU Xiao-yuan LIN Zhi-hua 《光谱学与光谱分析》2004,(5)
用FTIR ,NIRFT Raman ,UV VisDRS和荧光光谱等对五个新型具有 [(PO4) 4 MoⅤ6O15]12 -阴离子簇的化合物 :Na·(H4TETA) 3 ·(H3 O) 5·{Zn[(HPO4) 2 (PO4) 2 Mo6O15]2 } (2 ) ,(H2 en) 7·(H3 O) 4 ·{Cu[(HPO4) 2(PO4) 2 Mo6O15]2 }·H2 O (3) ,(H3 DETA) 2 ·(H3 O) 3 ·{Co0 5[(HPO4) 2 (PO4) 2 Mo6O15]}·H2 O (4) ,[Co(H3 TETA) ]2 {Co0 5[(HPO4) (PO4) 3 Mo6O15]}· 3 5H2 O (5 )和 (H3 DETA)· (H3 O ) 4 · {Co1 5[(HPO4) 2(PO4) 2 Mo6O15]}·0 5H2 O (6 ) ,进行研究 ,并探讨其结构和性能的关系。这些化合物具有 {M [(PO4) 4 Mo6O15]2 }二聚体单元 ,化合物 2~ 4的二聚体间通过与有机分子和水分子的氢键形成三维网状结构 ;化合物 5和 6的 {Co[(PO4) 4 Mo6O15]2 }二聚体间是分别通过 [CoH3 TEATA]基团和CoO4四面体组成网状结构。磷钼酸盐的特征振动频率和这些化合物的结构相关 ;化合物的三个UV VisDRS特征谱带分别属于Od→Mo,Oμ→Mo和O→M电荷转移 ;观察到以 2 4 0nm激发 ,在 4 10nm附近出现的由Oμ→Mo跃迁激发引起的较强的荧光发射谱带。 相似文献
994.
We consider the effect of clustering coefficient on the synchronizability of coupled oscillators located on scale-free networks. The analytic result for the value of clustering coefficient aiming at a highly clustered scale-free network model, the Holme-Kim model is obtained, and the relationship between network synchronizability and clustering coefficient is reported. The simulation results strongly suggest that the more clustered the network, the poorer the synchronizability. 相似文献
995.
The double complex symmetric gravitational theory is extended to the parametric symmetric gravitational theory by introducing a parameter β. Hence parametric Friedmann-Robertson-Walker equations are obtained and some characters of dark energy in corresponding spaces are discussed by taking different values of β. In our method some previous results can be included as the special case of our results. It is worth noting that some characters of dark energy can be more intuitively described in our model. By analysis, we can predict that the fate of universe would be a Big Rip in the future, and also find that the state parameters for the two different constraint conditions wФ are consistent with the present cosmological observations. 相似文献
996.
We study the electronic structures of LiMn2O4 by x-ray and ultraviolet photoelectron spectroscopy (XPS, UPS) and resonant photoelectron spectroscopy (RPES). XPS data suggest that the average oxidation state of Mn ions is 3.55, probably due to the small amount of lithium oxides on the surface. UPS and RPES data imply that Mn ions are in a high spin state, and RPES results show strong Mn3d-O2p hybridization in the LiMn2O4 valence band. 相似文献
997.
The entropy squeezing properties for a two-level
atom interacting with a two-mode field via two different competing transitions
are investigated from a quantum information point of view. The influences
of the initial state of the system and the relative coupling strength between the atom and the field
on the atomic information entropy squeezing are discussed. Our results show that
the squeezed direction and the frequency of the information entropy squeezing
can be controlled by choosing the phase of the atom dipole and the relative competing
strength of atom-field, respectively.
We find that, under the same condition, no atomic variance squeezing is predicted from the
HUR while optimal entropy squeezing is obtained from the EUR, so the quantum information
entropy is a remarkable precision measure for the atomic squeezing
in the considered system. 相似文献
998.
999.
1000.