Abstract

This review is dedicated to the topic of longitudinal rheology, a branch of rheology that is complementary to traditional shear rheology, and yet not as widely explored. Longitudinal rheology differs from typical shear rheology by the type of stress applied. Longitudinal stress is a wave, which causes liquid expansion and compression that occurs when ultrasound propagates through such liquid. The penetration depth of a longitudinal stress is much longer than for a shear stress, which allows this method to be used for studying liquid bulk properties at the MHz range. The concept of longitudinal rheology has been known for centuries, but only became available in commercial instruments as recently as the 1990s. We describe here the main principles of this technique, as well as present an overview of existing published applications, which include:

—Bulk viscosity

—Microviscosity

—Hookean coefficient of inter-particle bonds

—Newtonian liquid test at MHz range

—Compressibility

—Sol-gel transition

—Micellar systems

—Dissolution of polymers

—Liquid mixtures

中文翻译：

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纵向（超声）模式下的流变学。审查

摘要

这篇评论是专门针对纵向流变学的，这是流变学的一个分支，与传统的剪切流变学是互补的，但尚未得到广泛的研究。纵向流变学与典型的剪切流变学的不同之处在于所施加的应力类型。纵向应力是一个波，当超声波通过这种液体传播时，会引起液体膨胀和压缩。纵向应力的穿透深度比剪切应力的穿透深度长得多，这使得该方法可用于研究MHz范围内的液体体积特性。纵向流变学的概念已经有数百年的历史了，但直到1990年代才在商业仪器中出现。我们在这里描述该技术的主要原理，并概述现有已发布的应用程序，其中包括：

—堆积粘度

—微粘度

—粒子间键的霍克系数

—牛顿液体测试，MHz范围

—可压缩性

-溶胶凝胶转变

—胶束系统

—聚合物溶解

—液体混合物