标题： Kärger模型与双指数模型：理论见解和实验验证 显示英文标题

标题： The Kärger vs bi-exponential model: theoretical insights and experimental validations

摘要： 我们修订了三种常见的模型，用于解释脉冲梯度自旋回波测量中的水交换：一个具有时间依赖性水分数的双指数模型，Kärger 模型，以及一个为受限扩散设计的修改后的 Kärger 模型，例如在细胞内部的情况。 这三个模型进行了比较，并应用于酵母细胞悬浮液的实验数据。 Kärger 模型和修改后的 Kärger 模型得出的结果非常接近，并能准确拟合数据。 虽然双指数模型不够严谨，但它具有自然的物理解释，并暗示了一种新的实验方法来估计水交换时间。 显示英文摘要

摘要： We revise three common models accounting for water exchange in pulsed-gradient spin-echo measurements: a bi-exponential model with time-dependent water fractions, the K\"arger model, and a modified K\"arger model designed for restricted diffusion, e.g. inside cells. The three models are compared and applied to experimental data from yeast cell suspensions. The K\"arger model and the modified K\"arger model yield very close results and accurately fit the data. The bi-exponential model, although less rigorous, has a natural physical interpretation and suggests a new experimental modality to estimate the water exchange time.