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991.
An energy theory is proposed on the buckling of a ferromagnetic thin plate in a transverse static magnetic field. The analytic
solution of critical field for plates is obtained by using variational method. It is shown that the critical magnetic field
is not only influenced by the ratio of the thickness to the length, but also by the width, total length and the magnetic susceptibility
of the specimen. Theoretical calculations agree with experiments reasonably. 相似文献
992.
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
993.
994.
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
995.
A new calculation method was discussed to treat the Hückel Hamiltonian of any fullerene with a certain point group symmetry. This method was applied to calculating the electronic energy levels of icosahedral fullerenes C\-n(I\-h: n=60h 2, 0相似文献
996.
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
997.
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
998.
Colony-stimulating factor-1 (CSF-1), which is necessary for cell proliferation and differentiation, regulates both immediate
and delayed early responses throughout G1 phase. The binding of CSF-1 to its receptor (CSF-1R) triggers phosphorylation of
the receptor and its intrinsic tyrosine kinase. The activated receptor binds directly to cytoplasmic effector proteins, which
induce multiple-signal transduction pathways. CSF-1 can induce the c-myc gene expression via Ras and Ets-related proteins.
The expression of c-fos/jun family genes is also targeted following the activation of Ras. CSF-1R activates STAT1 and STAT3
to participate in signaling, but JAKs do not appear to contribute to signaling by CSF-1R. CSF-1R activates PI3-kinase, and
PI3-ki can interact with downstream proteins by the MAPKK-related pathway independent of Ras/Raf. PC-PLC can enforce signaling
in response to CSF-1. Furthermore, the turnover and dephosphorylation by the phosphatase SHPTP1 of CSF-1R are the major mechanism
in the negative regulation of signaling by CSF-1R 相似文献
999.
Identification and classification of subspecies of Asian cultivated rice and their hybrids 总被引:2,自引:0,他引:2
Xiangkun Wang Renhua Li Chuanqing Sun Zichao Li Hongwei Cai Xinli Sun 《科学通报(英文版)》1998,43(22):1864-1864
Having reviewed the major classification systems proposed by various scholars across the world, it is found thatindica andjaponica underO. sativa L. are two major directions thoroughly differentiated from the Asian cultivated rice, forming the framework of the classification
structure. A system withindica andjaponica as the only two subspecies is therefore reiterated. There are various ways to determine the indica-japonica identity of hybrid
rice, but the “combined morphological trait index” (CMT index) method is more efficient and easier to handle, although the
isozyme analysis, molecular marker analysis and grain quality assay methods are also feasible. 相似文献
1000.
Carbon isotope anomaly in marbles associated with eclogites from the Dabie Mountains 总被引:1,自引:0,他引:1
This is a report of carbon isotope anomaly in marbles associated with the UHP eclogites from the Dabie Mountains. The results
place constraints on the degree of crust-mantle interaction during the UHP metamorphism. 相似文献