浓度是描述溶液特性的重要物理量，随温度的改变而发生变化. 基于超声光栅测量透明液体中声速的方法，以透明溶液氯化钠溶液为例，通过控制变量法研究了声速、浓度、温度三者之间的关系，最终定量得出三者所满足的方程，实现了不同温度下浓度的测量. 结果表明，该方法测量液体浓度置信度高，相对误差小，且广泛适用于透明液体浓度的测量，具有时效性高、反映时间短、精度高等优点。

Concentration is an important physical quantity to describe the properties of a solution. It changes with the change of temperature. Based on the method of ultrasonic grating measurement of sound velocity in transparent liquid, taking transparent sodium chloride solution as an example, the relationship among sound velocity, concentration and temperature is studied through the control variable method. Finally, the equations of these three parameters is obtained quantitatively, and the concentration is measured at different temperatures. The results show that the method has high confidence and small relative error, and is widely applicable to the measurement of transparent liquid concentration. It has the advantages of high timeliness, short response time and high precision.