Abstract: A probe for measuring a sample solution includes an outer body configured to receive an operational amount of a reference solution, and a sensor assembly including an inner body at least a portion of which is located inside the outer body. A shield is positioned between the outer surface of the inner body and the inner surface of the outer body. The shield is configured to be in contact with the reference solution and extends above the top surface of the reference solution when the probe is filled with an operational amount of the reference solution.

Abstract: A self-cleaning analyzer system for sensing a chemical characteristic of a fluid sample according to one embodiment includes a sensing chamber including a sample inlet configured to receive the fluid sample and a sample outlet; a sensor configured to sense the chemical characteristic of the fluid sample in the sensing chamber; a plurality of cleaning beads contained in the sensing chamber; and an agitator configured to stir the fluid sample in the sensing chamber. One or more of the plurality of cleaning beads contact the sensor when the agitator stirs the fluid sample. A method for sensing a chemical characteristic of a fluid sample using a self-cleaning analyzer system according to one embodiment includes providing the fluid sample to the sensing chamber; sensing the chemical characteristic of the fluid sample; and stirring the fluid sample causing one or more of the plurality of cleaning beads to contact the sensor.

Abstract: A method of measuring oxidant in an aqueous composition using an electrode system comprising a membrane permeable to a species to be measured, a cathode situated behind the membrane, and an electrolyte between the membrane and cathode. Embodiments of the method may include contacting the membrane and an anode with the aqueous composition, and measuring the current between the cathode and anode in response to a first voltage applied between them. A pulse of a second voltage may be applied between the cathode and the anode, where the second voltage is different from the first voltage. Apparatus and computer program products which may perform the method, are also provided.

Abstract: A method of measuring oxidant in an aqueous composition using an electrode system comprising a membrane permeable to a species to be measured, a cathode situated behind the membrane, and an electrolyte between the membrane and cathode. Embodiments of the method may include contacting the membrane and an anode with the aqueous composition, and measuring the current between the cathode and anode in response to a first voltage applied between them. A pulse of a second voltage may be applied between the cathode and the anode, where the second voltage is different from the first voltage. Apparatus and computer program products which may perform the method, are also provided.

Abstract: A method of measuring oxidant in an aqueous composition using an electrode system comprising a membrane permeable to a species to be measured, a cathode situated behind the membrane, and an electrolyte between the membrane and cathode. Embodiments of the method may include contacting the membrane and an anode with the aqueous composition, and measuring the current between the cathode and anode in response to a first voltage applied between them. A pulse of a second voltage may be applied between the cathode and the anode, where the second voltage is different from the first voltage. Apparatus and computer program products which may perform the method, are also provided.

Abstract: A low maintenance reference electrode has a liquid junction body with a multiplicity of micron-sized capillary channels extending through the body for transporting electrolyte to a test solution. A viscosity-increasing agent thickens the electrolyte to limit its flow to a rate on the order of microliters/day so that a few milliliters of electrolyte suffice to provide an extended electrode life.

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: A low maintenance reference electrode has a liquid junction body with a multiplicity of micron-sized capillary channels extending through the body for transporting electrolyte to a test solution. A viscosity-increasing agent thickens the electrolyte to limit its flow to a rate on the order of microliters/day so that a few milliliters of electrolyte suffice to provide an extended electrode life.

Abstract: A low maintenance reference electrode has a liquid junction body with a multiplicity of micron-sized capillary channels extending through the body for transporting electrolyte to a test solution. A viscosity-increasing agent thickens the electrolyte to limit its flow to a rate on the order of microliters/day so that a few milliliters of electrolyte suffice to provide an extended electrode life.

Abstract: A measurement/calibration cell for potentiometrically measuring ion concentration in a fluid interposes a barrier between measuring and reference electrodes and positions the measuring electrode at a sufficiently higher gravimetric potential above the reference electrode that seepage of electrolyte from the latter to the former is effectively precluded. A controller associated with the cell displays instructions and other desired information on a scrolling display such that a substantial amount of information can be presented in a relatively small display window.

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: A fluoride monitoring electrode comprises a single crystal of a lanthanum series fluoride doped with alkaline earth ions. The sample pre-treatment solution used in conjunction with the electrode includes a buffer that maintains a pH of 5 to 8 and a complexing agent that complexes iron and aluminum.

Abstract: A low maintenance reference electrode has a liquid junction body with a multiplicity of micron-sized capillary channels extending through the body for transporting electrolyte to a test solution. A viscosity-increasing agent thickens the electrolyte to limit its flow to a rate on the order of microliters/day so that a few milliliters of electrolyte suffice to provide an extended electrode life.

Abstract: A fluoride monitoring electrode comprises a single crystal of a lanthanum series fluoride doped with alkaline earth ions. The sample pre-treatment solution used in conjunction with the electrode includes a buffer that maintains a pH of 5 to 8 and a complexing agent that complexes iron and aluminum.

Abstract: A measurement/calibration cell for potentiometrically measuring ion concentration in a fluid interposes a barrier between measuring and reference electrodes and positions the measuring electrode at a sufficiently higher gravimetric potential above the reference electrode that seepage of electrolyte from the latter to the former is effectively precluded. A controller associated with the cell displays instructions and other desired information on a scrolling display such that a substantial amount of information can be presented in a relatively small display window.

Abstract: Described is a combination, PVC-membrane, Ion-Selective Electrode (ISE) with a replaceable sensing module and a single-junction, sleeve-type reference electrode. pH and ion-selective electrodes (ISEs) in the "Combination" configuration, i.e., single probes containing both the sensing and reference half-cells, are more convenient, more economical, and can be used to analyze smaller samples than an equivalent pair of separate half-cell electrodes.

Abstract: Described is a combination, PVC-membrane, Ion-Selective Electrode (ISE) with a replaceable sensing module and a single-junction, sleeve-type reference electrode. pH and ion-selective electrodes (ISEs) in the "Combination" configuration, i.e., single probes containing both the sensing and reference half-cells, are more convenient, more economical, and can be used to analyze smaller samples than an equivalent pair of separate half-cell electrodes.

Abstract: The present invention is a reagent which, when added as a conditioning solution to samples containing calcium and magnesium, selectively converts the calcium into a complex which does not interfere with magnesium ISEs, and thus allows accurate magnesium determinations by ISE in a wide variety of samples. The conditioning solution also eliminates strontium and barium interferences by the same mechanism, but these are of secondary importance because they occur in samples less frequently and because they interfere less severely. Also, the formulation of the reagent was optimized solely in order to eliminate calcium interference and its ability to remove strontium and barium interferences was surprisingly fortuitous.