Pegg D E, Hayes A R, Diaper M P
Pflugers Arch. 1984 Jun;401(2):209-12. doi: 10.1007/BF00583884.
The accurate measurement of flow rates in isolated-organ perfusion experiments remains a problem. This paper describes an instrument that is based upon the familiar drop counter, but permits greater accuracy, resolution and convenience of recording output than has hitherto been available with such a device. Long-term stability at low flow rates is excellent. The input transducer is a conventional drip chamber with platinum electrodes arranged so that each drop produces an electrical pulse. The time between pulses is measured (or groups of 10 pulses for higher flow rates) and a voltage output proportional to flow is derived by analogue computing elements. Calibration requires only the measurement of the volume of drops forming at very low flows, and a simple procedure to do this is described. Four switched ranges covering 0.1-30 ml/min are provided, and the agreement between flow recorded by the instrument and by timed collections of perfusate is generally better than 3% of full scale.
在离体器官灌注实验中，准确测量流速仍然是一个问题。本文介绍了一种基于常见滴数计数器的仪器，但它在记录输出方面比以往此类装置具有更高的准确性、分辨率和便利性。在低流速下具有出色的长期稳定性。输入换能器是一个传统的滴液室，配有铂电极，其布置方式使得每一滴都会产生一个电脉冲。测量脉冲之间的时间（对于较高流速则测量10个脉冲的组），并通过模拟计算元件得出与流速成比例的电压输出。校准仅需测量在极低流速下形成的液滴体积，并描述了一个简单的操作程序。该仪器提供四个切换量程，覆盖0.1 - 30毫升/分钟，仪器记录的流速与定时收集灌注液之间的一致性通常优于满量程的3%。
