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通过近一年的“大学物理学”教材的使用,开始逐步学习到了在教学中怎样建立与培养学生科学研究的意识以及进行科学研究的操练,同时也目睹了研究性教学所发挥的潜在作用. 相似文献
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Hawking radiation of Weyl neutrinos in a rectilinearly non—uniformly accelerating Kinnersley black hole 下载免费PDF全文
The quantum thermal effect of Weyl neutrinos in a rectilinearly non-uniformly accelerating Kinnersley black hole is investigated using the generalized tortoise coordinate transformation.The equations that determine the location,the Hawking temperature of the event horizon and the thermal radiation spectrum of neutrinos are derived.Our results show that the location and the temperature of the event horizon depend not only on the time but also on the angle. 相似文献
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To clarify the randomness of protein sequences,we make a detailed analysis of a set of typical protein sequences representing each fold by using the nonlinear prediction method developed in nonlinear dynamics theory.No deterministic structures are found in these protein sequences and this implies that they behave as random chains.We also explain the controversial results obtained in previous investigations. 相似文献
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From Discreteness to Continuity: Dislocation Equation for Two-Dimensional Triangular Lattice 下载免费PDF全文
A systematic method from the discreteness to the continuity is presented for the dislocation equation of the triangular lattice. A modification of the Peierls equation has been derived strictly. The modified equation includes the higher order corrections of the discrete effect which are important for the core structure of dislocation. It is observed that the modified equation possesses a universal form which is model-independent except the factors. The factors, which depend on the detail of the model, are related to the derivatives of the kernel at its zero point in the wave-vector space. The results open a way to deal with the complicated models because what one needs to do is to investigate the behaviour near the zero point of the kernel in the wave-vector space instead of calculating the kernel completely. 相似文献
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Using the daily precipitation data of 740 stations in China from 1960 to 2000, the analysis on the variations and distributions of the frequency and the percentage of extreme precipitation to the annual rainfall have been performed in this paper. Results indicate that the percentage of heavy rains (above 25mm/day) in the annual rainfall has increased, while on average the day number of heavy rains has slightly reduced during the past 40 years. In the end of 1970s and the beginning of 1980s, both the number of days with extreme precipitation and the percentage of extreme precipitation abruptly changed over China, especially in the northern China. By moving t test, the abrupt change year of extreme precipitation for each station and its spatial distribution over the whole country are also obtained. The abrupt change years concentrated in 1978-1982 for most regions of northern China while occurred at various stations in southern China in greatly different/diverse years. Besides the abrupt change years of extreme precipitation at part stations of Northwest China happened about 5 years later in comparison with that of the country's average. 相似文献
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