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821.
The problems about the almost periodic solution to singular systems are studied. The criterion that the singular systems have
almost periodic solutions is obtained. At the same time, the applied example is given. 相似文献
822.
823.
On homotopy regular monomorphisms 总被引:1,自引:0,他引:1
Jixiang Chen 《科学通报(英文版)》1998,43(1):27-27
A concept of homotopy regular monomorphism is introduced which is strictly between homotopy monomorphism and homotopy equivalence.
And it characterizes homotopy equivalence in some sense. 相似文献
824.
Comprehensive evaluation of mechanism of “chimney effect” using principles of magnetism, geochemistry and mineralogy 总被引:1,自引:0,他引:1
Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data. 相似文献
825.
In the transitional region between the Loess Plateau and deserts, 4 sections located respectively at Yuling, Hengshan, Dingbian
and Huining of China are studied. The high-resolution paleoclimatic records obtained show that environmental events on varying
time scales have happened over East Asia. These events are dated with the time scales established using the recently-developed
approach of Automatic Orbital Tuning. This leads to the establishment of the chronology of the environmental events. 相似文献
826.
827.
The shear-wave splitting was analyzed on the deep seismic sounding profile crossing the Dabieshan area. The direction difference
between Sg and SmS fast wave polarization indicates that the modem regional tectonic stress field in the Dabieshan area exists
only in uppcr crust, while the crack alignment caused by the Triassic collision between the North China and the Yangtze blocks
had been preserved in mid-lower curst. 相似文献
828.
The fourth axiom in the definition of real random normed module is superfluous. A necesmry and sufficient condition is given
that continuous random linear functionals over complex random normed spaces are a. s. bounded, and furthermore, in the sense
of inometrical isomorphism it is proved the fourth axiom in the complex random normed module is superfluous. 相似文献
829.
An all solid-state electrochromic smart window employing prussian blue and electrodeposited WO3 film with poly (vinyl chloride) (PVC) gel electrolyte that has high conductivity (2 mS/cm) at room temperature has been fabricated
for the first time. The smart window has beell found to be excellent for electrochromism and memory characteristics. 相似文献
830.
InSb nanocrystals embedded in SiO2 thin films were prepared by rf magnetron cosputtering technique. THe observation by transmission electron microscope showed
that InSb nanocrystals dispersed uniformly in SiO2 matrices. InSb nanocrystals with different sizes can be obtained by changing the annealing condition. The average size of
InSb nanocrystals depended on annealing temperature and time, but not on the t1/3 rules. X-ray photoelectron spectroscopy and X-ray diffraction were also applied to the analyses of the composite thin films. 相似文献