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 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: An analytical system for analyzing a liquid sample includes structure defining an analysis region with an inlet and an outlet, a polychromator system disposed in sensing relation to the analysis region, structure defining a sample inlet port, and structure connecting the sample inlet port to the inlet of the analysis region. The analysis region includes sample excitation apparatus with a pair of spaced metal electrodes, one of the electrodes having an upper surface in spaced juxtaposition to the other electrode and passage structure connected to the inlet of the analysis region. The one metal electrode is disposed with the passage structure extending to an outlet port in the upper surface, and structure in the upper surface defines a plurality of channels extending away from the outlet port of the passage structure for discharge of excess quantities of a liquid sample to be analyzed flowed through the passage structure.

Abstract: An analytical system for analyzing a liquid sample that includes structure defining an analysis region with an inlet and an outlet, a spectrometer system disposed in sensing relation to the analysis region, structure defining a sample inlet port, and structure connecting the sample inlet port to the inlet of the analysis region. The analysis region includes sample excitation apparatus with a pair of spaced metal electrodes, one of the electrodes having an upper surface in spaced juxtaposition to the other electrode and passage structure connected to the inlet of the analysis region, and the other electrode having a lower surface of annular configuration in spaced juxtaposition to the upper surface of the one electrode.

Abstract: A spectroanalytical system includes housing structure with vent structure open to the atmosphere; radiation dispersing apparatus in the housing structure for dispersing radiation into a spectrum for application to sensor apparatus; sample excitation apparatus for exciting sample material to be analyzed to spectroemissive levels for generating a beam of radiation for dispersion by the dispersing structure; a source of gas; structure for flowing gas from the source into the housing structure for exhaust from the housing structure through the vent structure at a flow rate that is less than one percent of the volume of the housing structure per hour; first control structure for maintaining the pressure of the gas in the housing structure at a constant (within about one millibar) pressure independent of atmospheric pressure; and second control structure for maintaining the temperature of the gas within the housing structure constant within about 0.1.degree. F. during system operation.