Abstract: Temperature compensation for ion-selective electrodes is obtained by positioning a temperature-measuring element in a chamber of limited thermal mass which is in thermal contact with the measuring electrode filling solution but is thermally isolated from other filling solutions in the electrode. In a preferred embodiment, the temperature-measuring element comprises a thermistor enclosed within thin flexible tubing; the electrical leads of the thermistor are forced against a segment of the inner wall of the tubing by an elongated strand of material abutting the thermistor to enhance heat transfer with the thermistor.

Abstract: An improved combination ion-selective electrode has a thin ion-sensing body extending from an outer reference body. The exposed portion of the ion-sensing body is encompassed by a sleeve which effectively forms an extension of the reference body and also provides mechanical stability to the ion-sensing body. One or more fluid channels are formed interior to the sleeve to provide an electrically conductive path from the reference solution within the reference body to the tip of the electrode.

Abstract: Temperature compensation for ion-selective electrodes is obtained by positioning a temperature-measuring element in a chamber of limited thermal mass which is in thermal contact with the measuring electrode filling solution but is thermally isolated from other filling solutions in the electrode. In a preferred embodiment, the temperature-measuring element comprises a thermistor enclosed within thin flexible tubing; the electrical leads of the thermistor are forced against a segment of the inner wall of the tubing by an elongated strand of material abutting the thermistor to enhance heat transfer with the thermistor.

Abstract: An improved combination ion-selective electrode has a thin ion-sensing body extending from an outer reference body. The exposed portion of the ion-sensing body is encompassed by a sleeve which effectively forms an extension of the reference body and also provides mechanical stability to the ion-sensing body. One or more fluid channels are formed interior to the sleeve to provide an electrically path from the reference solution within the reference body to the tip of the electrode.

Abstract: Disclosed are combination glass pH electrodes, the standard potential of which is stabilized by means one or more of the following structural modifications: (a) incorporating a noble metal internal element in the pH half-cell; (b) incorporating a noble metal internal element in the reference half-cell; (c) incorporating an internal pH bulb electrolyte with stable pH and oxidation-reduction potential; (d) incorporating an homogenous reference electrolyte with stable oxidation-reduction potential and equitransferent salt; (e) incorporating a liquid junction composed of a porous, inert material; (f) incorporating a reference electrolyte compartment vent; (g) incorporating a storage sleeve, with or without an absorbent medium located therein.

Abstract: An improved ion-selective electrode with enhanced sensitivity and reliability. The electrode is readily formed from an electrode assembly sealingly joined to the upper end of an electrode chamber whose lower end opens into in a tube bore of substantial path length that provides a conductive path between the electrode assembly and a sensing tip of the electrode. The electrode assembly itself takes the form of a generally helical coil formed on a post extending from the upper end of the assembly and positioning a substantial length of conductive lead remote from the sensing tip of the electrode. The electrode chamber is thermally insulated from the main body of the electrode, and adverse temperature effects are thus greatly minimized. A self-cleaning junction has also been developed. Increased reliability for a given sensitivity have been found to result from the construction.

Abstract: Disclosed are combination glass pH electrodes, the standard potential of which is stabilized by means one or more of the following structural modifications: