There are many long and elastic round cross-section rod structures in quayside container crane, whose frequency are so low that it is easy to arouse crosswind resonance.

岸边起重机结构中有许多长的弹性圆截面杆件，自振频率比较低，很容易发生横风共振。

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The large TPA cross section may result from the intensive linear absorbance of the molecule due to its conjugate rigid plane structure, and the two-photon resonance excitation condition.

该分子具有大的TPA截面是起源于该分子的刚性平面共轭结构所固有的线性吸收特性和TPA共振增强；

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