Abstract: By changing the connection condition in the interface between the substrates and viscous liquid in the experiments, the shear elastic property of the liquid with several-ten-micron thickness can be observed under the condition of low shear-strain rate. To confirm the property, the strain-stress signals in the experiments were collected and processed by the discrete Fourier transformation (DFT). From the viewpoint of phase difference of strain and stress in rheology theory, it was proved that liquid has shear elastic properties under some small-scale dimension conditions.

Key words: vibration and wave, boundary connection, shear elastic, DFT, rheology, phase difference

摘要： 通过改善实验流体与基片的边界连接，发现粘性液体在几十μm的厚度下，以低速率、小应变剪切即使远离其相变温度，也可以观察到其具有剪弹性动力学特性。为了进一步揭示这种特性，采集实验中的应力-应变信号，并应用离散傅立叶变换（DFT）对信号进行分析，根据流变学理论从应力与应变的相位差角度证明液体在一定条件下存在剪弹性特性。

关键词: 振动与波, 边界连接, 剪弹性, 离散傅立叶变换, 流变学, 相位差