熱電冷却による0°C～50°C可変恒温槽の試作
1961 年 30 巻 2 号 p. 112-117
詳細
1961 年 30 巻 2 号 p. 112-117
In biological and medical research, it is often necessary to keep a sample at constant temperature. Moreover, to know thermodynamic quantities of the sample such as entropy, activation energy, etc., a thermostatic bath which can be easily controlled in a wide range of temperature is highly desirable.
A thermoelectric system is applied for this purpose. A water bath of 100 ml is quickly cooled and warmed between 0°C and 50°C with 4 couples of thermoelements. The thermoelectric power of a couple is α=360×10-6 V deg-1.
Temperature is detected by a thermistor and read directly on a HYS type microammeter. With the aid of a small lamp and a phototransistor mounted on the scale of the ammeter, and a suitable amplifier-relay system, temperature is easily controlled within ±0.1°C.
Theoretical analysis and experimental proof for these thermoelectric systems are described.
