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研究了 KdV-Burgers-Kuramoto 方程的渐近吸引子,即利用正交分解法构造一个有限维解序列。首先用数学归纳法证明了该解序列不会远离方程的整体吸引子,接着证明解序列在长时间后无限趋于方程的整体吸引子,最后给出渐近吸引子的维数估计。 相似文献
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By means of the numerical solution of time-dependent Schr6dinger equation, we verify a scaling law of photoionization in ultrashort pulses. We find that for a given carrier-envelope phase and duration of the pulse, identical photoionizations are obtained provided that when the central frequency of the pulse is enlarged by k times, the atomic binding potential is enlarged by k times, and the laser intensity is enlarged by ka times. The scaling law allows us to reach a significant control over direction of photoemission and offers exciting prospects of reaching similar physical processes in different interacting systems which constitutes a novel kind of coherent control. 相似文献
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通过在介孔氧化硅材料中原位聚合的方法制备了三苯基膦功能化的有机聚合物@介孔氧化硅复合材料PPh3polymer@FDU-12.采用X射线衍射、氮气吸附脱附、透射电镜和热重等手段对其结构和组成进行了表征.该复合材料与金属前驱体Rh(acac)(CO)2配位后得到的固体催化剂,在长链烯烃1-辛烯的氢甲酰化反应中,醛选择性可达92%–96%,并表现出高于聚合物的活性(99%转化率).这主要归因于介孔氧化硅材料的高比表面积和有序的孔结构更有利于反应物和催化活性中心的接触.研究发现,调变复合材料中聚合物的含量或使用不同孔道结构的氧化硅载体(SBA-15,MCM-41和FDU-12)都会影响固体催化剂的反应活性和选择性.该方法得到的多相催化剂具有较好的循环使用性能,在循环使用15次后仍能保持较好的反应活性,但醛选择性有所降低. 相似文献
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研究了一类非线性梁方程的渐近吸引子.即利用正交分解法构造一个有限维解序列.首先用数学归纳法证明了该解序列不会远离方程的整体吸引子,其次证明了它在长时间后无限趋于方程的整体吸引子,并给出了渐近吸引子的维数估计. 相似文献
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The asymmetric photoionization of atoms irradiated by intense,
few-cycle laser pulses is studied numerically. The results show that
the pulse intensity affects the asymmetric photoionization in three
aspects. First, at higher intensities, the asymmetry becomes
distinctive for few-cycle pulses of longer durations. Second, as the
laser intensity increases, the maximal asymmetry first decreases
then increases after it has reached a minimal value. Last, the value
of the carrier-envelope phase corresponding to the maximal asymmetry
varies with the pulse intensity. This study reveals that the
increasing of pulse intensity is helpful for observing the
asymmetric photoionization. 相似文献