Abstract: A sensor service prediction system and method are provided for a sensor. The system monitors sensor operations of the sensor, and provides a calendar age odometer which increments a calendar age of the sensor by a first time interval as the sensor operates. The system further provides an accelerated age odometer which increments an accelerated age of the sensor by a second time interval according to the increment of the calendar age and a sensor temperature or other measurable environmental condition associated therewith. The system obtains a value of a sensor property at different calendar ages or accelerated ages of the sensor over time, and predicts and outputs when the sensor property of the sensor is anticipated to reach a sensor property threshold based on the values of the sensor property in relations to the accelerated age.

Abstract: A sensor service prediction system and method are provided for a sensor. The system monitors sensor operations of the sensor, and provides a calendar age odometer which increments a calendar age of the sensor by a first time interval as the sensor operates. The system further provides an accelerated age odometer which increments an accelerated age of the sensor by a second time interval according to the increment of the calendar age and a sensor temperature or other measurable environmental condition associated therewith. The system obtains a value of a sensor property at different calendar ages or accelerated ages of the sensor over time, and predicts and outputs when the sensor property of the sensor is anticipated to reach a sensor property threshold based on the values of the sensor property in relations to the accelerated age.

Abstract: A potentiometric sensor includes an elongate non-glass, non-metal housing having opposite first and second longitudinal ends and a length extending between the first and second longitudinal ends. The housing defines a lumen extending along the length of the housing. A measuring half-cell assembly is received in the lumen of the housing and secured to the housing. The measuring half-cell assembly includes a glass body having opposite first and second longitudinal ends and a length extending between the first and second ends of the glass body. The second longitudinal end of the glass body is adjacent the second longitudinal end of the housing and a longitudinal extent of the glass body is less than the length of the housing.

Abstract: A potentiometric sensor includes an elongate non-glass, non-metal housing having opposite first and second longitudinal ends and a length extending between the first and second longitudinal ends. The housing defines a lumen extending along the length of the housing. A measuring half-cell assembly is received in the lumen of the housing and secured to the housing. The measuring half-cell assembly includes a glass body having opposite first and second longitudinal ends and a length extending between the first and second ends of the glass body. The second longitudinal end of the glass body is adjacent the second longitudinal end of the housing and a longitudinal extent of the glass body is less than the length of the housing.

Abstract: A system for monitoring the viability of an electrochemical cell measures the impedance of the cell over a wide range of impedances and with diminished phase shift over prior methods so that a more nearly accurate assessment of the impedance can be made. The system is particularly useful for four electrode systems, but is not so limited. It may advantageously be incorporated in the cell itself to further minimize cabling artifacts.

Abstract: A pH half-cell method and apparatus includes an electrode, a pH sensitive glass membrane and an electrolyte in electrolytic contact with the electrode and membrane. The membrane includes at least about 15 mole percent lithium, and the electrolyte includes a lithium salt as the predominant monovalent cation. The pH half-cell is used with a reference half-cell and meter to provide an electrochemical potential measurement sensor, optionally with both half-cells disposed within a single housing. The lithium salt electrolyte is also used in a method for storing, conditioning, preserving and/or rehabilitating a pH half-cell.

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: A modular potentiometric sensor includes a housing having measuring and reference half-cells, a temperature sensor, and solution ground combination assembly. An electrical conductor of the combination assembly extends through the housing, while remaining electrically isolated from the housing and half-cells, terminating at an electrically and thermally conductive end cap. Seals at opposite ends of the housing permit portions of the half-cells and the combination assembly to extend therethrough. The seals, measuring half-cell, and the combination assembly define an electrolyte compartment for the reference half-cell. The end cap provides close thermal coupling to the test fluid while also serving as a test fluid ground that is electrically isolated from the electrolyte compartment.

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 pH half-cell method and apparatus includes an electrode, a pH sensitive glass membrane and an electrolyte in electrolytic contact with the electrode and membrane. The membrane includes at least about 15 mole percent lithium, and the electrolyte includes a lithium salt as the predominant monovalent cation. The pH half-cell is used with a reference half-cell and meter to provide an electrochemical potential measurement sensor, optionally with both half-cells disposed within a single housing. The lithium salt electrolyte is also used in a method for storing, conditioning, preserving and/or rehabilitating a pH half-cell.

Abstract: A system for monitoring the viability of an electrochemical cell measures the impedance of the cell over a wide range of impedances and with diminished phase shift over prior methods so that a more nearly accurate assessment of the impedance can be made. The system is particularly useful for four electrode systems, but is not so limited. It may advantageously be incorporated in the cell itself to further minimize cabling artifacts.

Abstract: A multimode electrochemical sensing array formed on an integrated circuit chip is structured to provide electrochemical determination of acidity or alkalinity, as well as electrochemical and potentiometric measurement of oxidation/reduction potentials, conductivity measurements, electrostatic discharge protection, and ground provisioning.

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:

Abstract: Disclosed is an electrochemical cell containing two or more electrodes wherein the half-cell potential of at least one electrode is determined by the concentration of a specific ion anticipated to be present in all test solutions, said ion concentration being measured in the cell by a first electroanalytical technique that does not depend on a known reference electrode potential, such that said electrode, its half-cell potential being calculable from the measured ion concentration, can then serve as a reference electrode in one or more subsequent electroanalytical techniques that do depend on a known reference electrode potential, said subsequent technique or techniques being carried out in the same cell.

Abstract: The present invention is directed to a stable, non-hazardous solution for calibrating oxidation-reduction potential (ORP) measurement cells. The redox standard calibration solution of the present invention consists essentially of an aqueous solution containing the triiodide/iodide redox couple. In a preferred embodiment, the solution of the present invention consists essentially of an aqueous solution containing up to about 0.01 moles per liter of iodine (I2) and at least about 1 mole per liter of potassium iodide. In a most preferred embodiment, the solution of the present invention consists of an aqueous solution of 4 molar potassium iodide (KI) and 0.0067 molar iodine (I2).

Abstract: The present invention provides an electrophoretic separation system on a planar chip of glass or plastic material with on-chip FIA (flow injection analysis) injection and one or multiple sets of electrodes for on-column, end-column, off-column electrical or electrochemical, suppressed or unsuppressed, conductiometric, high-frequency contactless conductiometric, potentiometric and amperometric detection.

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: Disclosed is a two-point calibration procedure, that when used with a mathematical algorithm, improves the accuracy of electrolytic conductivity measurements by correcting for non-linear behavior of conductivity cells. Unlike purely mathematical means of correcting for non-linearity which may use second or higher order equations, this algorithm has the following advantages: it is based on an analysis of the physical phenomena which are responsible for non-linearity; it yields one unique solution, i.e., it uses an equation that has only one root; and it yields diagnostic information concerning the behavior of the cell.