A new microwave cavity resonator for determining molecular orientation and dielectric anisotropy of sheet materials
A new microwave cavity resonator for determining molecular orientation and dielectric anisotropy of sheet materials
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DOI：
10.1063/1.1148152
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发表时间：
1997-06-01
影响因子：
1.6
通讯作者：
Osaki, S
中科院分区：
文献类型：
--
作者：
Osaki, S
研制了一种新型的快速测定片状材料分子取向和介电各向异性的微波仪器。它的谐振腔不同于传统的谐振腔，因为波导被一个狭窄的间隙隔开。因此，它由一对矩形波导组成，每个波导由虹膜板分隔。给定的片材被插入到差距中，并且可以围绕垂直于其平面的轴旋转。确定了光阑直径和缝隙宽度，以满足在差距中插入厚膜后，透射微波功率和Q值不明显下降的要求。垂直于片材照射偏振微波，并且当片材以每转6.0秒的速度旋转时，在每1度的旋转角处测量透射波强度。该操作快速给出与给定样品中的分子取向相关的信息。可以在任何旋转角度下进行介电测量，从而允许在几分钟内确定复介电常数的真实的和虚部的角度依赖性，并且因此确定片材的介电各向异性。(C)1997年美国物理研究所。
A new type of microwave instrument is developed for quick determination of the molecular orientation and dielectric anisotropy in sheet materials. Its cavity resonator differs from the conventional one in that the waveguide is separated by a narrow gap. Thus, it consists of a pair of rectangular waveguides, each partitioned by an iris plate. A given sheet is inserted into the gap, and can be rotated around the axis normal to its plane. The iris diameter and gap width are determined so as to meet the requirement that the transmitted microwave power and the Q value may not drop markedly after insertion of thick films into the gap. Polarized microwaves are irradiated perpendicularly to the sheet, and the transmitted wave intensity is measured at every 1 degrees of rotation angle as the sheet is rotated at a speed of 6.0 s per turn. This operation quickly gives information related to the molecular orientation in the given sample. Dielectric measurements can be made at any rotation angles, allowing the angular dependence of the real and imaginary parts of the complex dielectric constant and, thus, the dielectric anisotropy of the sheet to be determined in a few minutes. (C) 1997 American Institute of Physics.