Clark cell

Japanese: Clark cell（英語表記）Clarkcell

… E = 1.01864 - 4.06 x 10 ^-5 ( t - 20) - 9.5 x 10 ^-7 ( t - 20) ² + 1 x 10 ^-8 ( t - 20) ^3To obtain an accurate voltage using a cadmium standard cell, it is necessary to take care such as (1) not to allow a relatively large current (1 μA or more) to flow continuously for a certain period of time, (2) not to raise or lower the temperature too much (hysteresis will remain in response to temperature changes), and (3) not to tip it over or subject it to mechanical shock.A standard cell in which the cadmium of a cadmium standard cell is replaced with zinc and the cadmium sulfate with zinc sulfate is called a Clark cell, and the relationship between the electromotive force E (unit: V) and temperature t °C is given by the following equation: E = 1.4325 - 1.19 x 10 ^-3 ( t -15) - 7 x 10 ^-6 ( t -15) ² Clark cells have a larger temperature coefficient than cadmium standard cells, so they are not often used.

*Some of the terminology that mentions "Clark cell" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…E＝1.01864－4.06×10^－5(t－20)－9.5×10^－7(t－20)²＋1×10^－8(t－20)³カドミウム標準電池を用いて正確な電圧を得るためには，(1)比較的大きな電流(1μA以上)をある程度以上連続的に流さない，(2)温度をあまり上げ下げしない(温度変化に対するヒステリシスが残る)，(3)倒したり，機械的衝撃を与えたりしない，などの注意が必要である。なお，カドミウム標準電池のカドミウムを亜鉛に，硫酸カドミウムを硫酸亜鉛に変えた標準電池をクラーク電池Clark cellといい，起電力E(単位V)と温度t℃との関係は次式で与えられる。E＝1.4325－1.19×10^－3(t－15)－7×10^－6(t－15)²クラーク電池はカドミウム標準電池にくらべて温度係数が大きいので，あまり用いられない。…