| 摘要 |
<p>In the proposed method for operating an apparatus (1) for determining trace amounts of sodium ions in a liquid sample (2) by potentiometry, a reference electrode (4) and a sensing electrode (5) comprising a glass body (5a) are used. For reconditioning said sensing electrode (5), the glass body (5a) is exposed to a fluorine ions containing reconditioning liquid (8) which is nominally free from sodium ions. In particular, the reconditioning liquid (8) comprises less than 100 ppb of sodium ions. Preferably, said reconditioning liquid (8) is an aqueous solution of 1 % by weight of acetic acid and 1 % by weight of ammonium fluoride.</p> |
