Abstract: The invention generally relates to the filed of providing a liquid for human consumption. In particular, the invention relates to a system for channeling a liquid such as particularly an aqueous liquid such as water in a circuit and for controlling the contamination of the circulating liquid with microorganisms, as well as to a corresponding method using the same. Furthermore, the invention relates to a method for the effective energy saving in the course of providing a heated liquid for human consumption while controlling the limit values recommended, admissible or acceptable for microorganisms, in which the set temperature of a heating device (8) is adjusted to a value below 60° C., preferably to a value between 40 and 55° C., most preferably to a value between 43 and 48° C.

Abstract: According to at least one aspect of the present disclosure, a reference half-cell for an electrochemical sensor for measuring a medium is disclosed. The reference half-cell includes a housing defining a chamber containing an electrolyte, the housing including a wall having an aperture therethrough, and an electrode disposed in the electrolyte in the chamber. The reference half-cell further includes a reference junction disposed in the aperture such that an interface between the reference junction and the housing wall is impermeable. The reference junction is electrically or ionically conductive and impermeable to the measured medium and the electrolyte, and the reference junction enables a constant potential at the electrode. An electrochemical sensor and oxidation-reduction potential sensor employing the reference junction are also disclosed.

Abstract: The present disclosure relates to an amperometric sensor for determining measurement values of a measurand representing a chlorine dioxide content of a measuring fluid, the sensor including a sensor housing in which a housing chamber is formed, a membrane sealing the housing chamber, a working electrode arranged within the housing chamber, a counter electrode arranged within the housing chamber, an inner electrolyte contained in the housing chamber and in contact with the membrane, the working electrode and the counter electrode, the inner electrolyte having a pH value between 3.5 and 9, inclusive, and a pH buffer stabilizing the inner electrolyte. The sensor further includes a measurement circuit electrically connected with the working electrode and the counter electrode and configured to apply a predetermined, constant voltage between the working electrode and the counter electrode and to generate at least one measurement signal representing a measurement value of the measurand.

Abstract: There are provided a biosensor, and a measurement device in which the biosensor is used, with which accurate puncture is enabled and reliability of measurement results are improved. The biosensor comprises an element substrate, a detector, a connection terminal, a continuity path, and a cutout. The detector is provided over the element substrate, and receives a specimen and detects a specific component contained in the specimen. The connection terminal is provided over the element substrate and acquires current corresponding to the specific component. The continuity path connects the connection terminal and the detector. The cutout is formed along the outer periphery of the detector so as to surround two or more directions of the detector.

Abstract: An apparatus, a control unit and a method are provided for detecting a concentration of chlorate-ions in an aqueous solution containing different types of chlorine oxidants. By applying energy to a defined volume of the aqueous solution to trigger a transformation of substantially all chlorine oxidants and/or chlorine therein to chloride and/or chlorate, and detecting the concentration of chlorate-ions contained in the defined volume, a solution can be provided that enables a simple and cheap measurement for a concentration of chlorate ions in an aqueous solution and that is capable for online measurement of such chlorate concentrations.

Abstract: Oxidation/reduction measurement is described. An aspect provides an oxidation/reduction quantification method, including: receiving intermittent oxidizer/reducer reference measurements from one or more reference sensors; receiving one or more substantially continuous oxidizer/reducer-related measurements from one or more corroboration sensors; and processing the one or more substantially continuous oxidizer/reducer-related measurements with the intermittent oxidizer/reducer reference measurements to generate substantially continuous representative oxidizer/reducer measurements. Other aspects are described.

Abstract: A chronoamperometric method and device to determine concentration of an electrochemically active species in a fluid and pH of the fluid. A plurality of sets of calibration relationships may be determined for a sensor in an aqueous solution, the sensor having one or more working electrodes and one or more reference electrodes. A first plurality of potentials may be applied across the working and reference electrodes of the sensor in solution, and a first plurality of currents and current differences obtained as a function of the applied first plurality of potentials. Concentration of an electrochemically active species may then be determined as a function of the obtained first plurality of currents and current differences using the plural sets of calibration relationships, and pH of the solution may be determined as a function of the obtained first plurality of currents and current differences using the plural sets of calibration relationships.

Abstract: An electrochemical sensor for the detection and analysis of an analyte in a solution is disclosed. The electrochemical sensor has an electrically non-conductive support; a plurality of electrodes on the support, each electrode having a first surface and an opposite second surface, said first surface facing towards the support and the second surface facing away from the support. The plurality of electrodes includes a reference electrode, a counter electrode, and a working electrode. The working electrode has a reagent composition containing a reagent for detecting an analyte applied directly to the second surface of the working electrode.

Abstract: An electrochemical sensor for the detection and analysis of an analyte in a solution is disclosed. The electrochemical sensor has an electrically non-conductive support; a plurality of electrodes on the support, each electrode formed from an electrode material and having a first surface and an opposite second surface, said first surface facing towards the support and the second surface facing away from the support. The plurality of electrodes includes a reference electrode, a counter electrode, and a working electrode. The working electrode has a reagent composition containing a reagent for detecting an analyte applied directly to the second surface of the working electrode or dispersed throughout the electrode material of the working electrode.

Abstract: A method for determining a salt concentration of a hydrocarbon fluid using a conductivity sensor and a hydrocarbon testing solution includes forming the hydrocarbon testing solution. The electropolymerizable monomer is operable to form a resultant associated polymer at a peak potential of the electropolymerizable polymer. The method includes introducing the hydrocarbon testing solution into the conductivity sensor. The method includes inducing a range of potential across the hydrocarbon testing solution such that at least a portion of the electropolymerizable monomer polymerizes. The range of induced potential includes the peak potential of the electropolymerizable polymer. The method includes detecting a range of electrical current associated with the range of potential induced. The method also includes the step of determining the salt concentration of the hydrocarbon fluid using the range of potential induced and the range of electrical current detected.

Abstract: This disclosure relates to a method of detecting an analyte. The method includes (1) contacting an aqueous solution containing the analyte with an electrochemical detector having a working electrode, a counter electrode, and a solid electrolyte, where the analyte includes a halogen or an oxy-halogen species and the solid electrolyte provides an electrical pathway between the working and counter electrodes; (2) applying a voltage to the detector; and (3) measuring the resultant current change in the detector.

Abstract: A method is provided for measuring an electrolytically-active species concentration in an aqueous or non-aqueous solution for use in providing control of the concentration of the species in a source solution thereof based on the measurements. In the method, a sample containing an electrolytically-active species is added into a measurement cell that has a working electrode and an auxiliary electrode, and a constant current is applied to the measurement cell while the working and auxiliary electrodes are in contact with the sample with monitoring of voltage difference across the electrodes until a change in the voltage difference is detected. A feedback signal is generated based on a parameter of the change in the voltage difference that is directly proportional to the amount of the electrolytically-active species in the sample, which can be used for process control. An apparatus is also described.

Abstract: A method for determining a concentration of an analyte is disclosed. The method includes applying a potential excitation to a fluid sample containing an analyte and determining if a current decay curve associated with the fluid sample has entered an analyte depletion stage. The method also includes measuring a plurality of current values associated with the fluid sample during the analyte depletion stage and calculating an analyte concentration based on at least one of the plurality of current values.

Abstract: The present invention is directed to the detection of target analytes using electronic techniques, particularly AC techniques.

Abstract: Provided are a method for measuring hydrofluoric acid content in a lithium secondary battery electrolyte and an analytical reagent composition used in the same.

Abstract: A titration apparatus comprising a titration reservoir for a non-flowing sample solution to be titrated; an ion source reservoir comprising an ion source solution of selected ions; an ion exchange membrane barrier capable of passing ions from the ion source solution to the titration reservoir, but of blocking bulk liquid flow; a first electrode in electrical communication with the ion source reservoir; and a second electrode in electrical communication with the titration reservoir. Also, an electrolytic titrant generator for use in the titration apparatus.

Abstract: Disclosed herein are methods and devices for evaluating ex-situ chemical degradation of fuel cell membranes. One embodiment of a method for evaluating ex-situ chemical degradation of a membrane comprises submerging a membrane in Fenton solution in a reaction vessel with a non-reactive weight configured to maximize exposure of the membrane to the Fenton solution, sealing the reaction vessel, heating the reaction vessel at a fixed rate to a predetermined temperature, holding the reaction vessel at the predetermined temperature for a predetermined test period, cooling the reaction vessel to room temperature, removing the membrane and analyzing the Fenton solution for fluoride ions.

Abstract: The present invention includes sensors and systems that include a sensor. A sensor includes a sensor polymer, where the polymer includes a repeating unit having an anilineboronic acid-phosphate complex or an anilineboronic acid complexed with an alcohol or diol. The sensor polymer may be a copolymer, such as a random copolymer, a block copolymer, or an alternate copolymer. The present invention also provides methods for using the sensors described herein, including methods for detecting the presence of an analyte, such as CO2, in a fluid.

Abstract: An apparatus, a control unit and a method are provided for detecting a concentration of chlorate-ions in an aqueous solution containing different types of chlorine oxidants. By applying energy to a defined volume of the aqueous solution to trigger a transformation of substantially all chlorine oxidants and/or chlorine therein to chloride and/or chlorate, and detecting the concentration of chlorate-ions contained in the defined volume, a solution can be provided that enables a simple and cheap measurement for a concentration of chlorate ions in an aqueous solution and that is capable for online measurement of such chlorate concentrations.

Abstract: A process for the simultaneous determination of chlorine and chlorate in sodium hypochlorite. First and second streams of sodium hypochlorite are provided. The first stream is treated to generate iodine indicative of chlorine. The second stream is treated to generate iodine indicative of chlorine and chlorate. The iodine of the first stream is subjected to an amperometric measuring cell to generate a first current proportional to a chlorine concentration of the first stream. The iodine of the second stream is subjected to an amperometric measuring cell to generate a second current proportional to the chlorine and chlorate concentration in the second stream. The first current is subtracted from the second current to determine an amount of chlorate.

Abstract: A method and apparatus measures the presence of total residual oxidant species in aqueous environments. More specifically, the apparatus is operable to measure hypohalites (e.g., hypochlorite and hypobromite) in water containing halide salts using electrochemistry. The apparatus can be a sensor having four electrodes—a reference electrode, a working electrode, and two auxiliary electrodes. The fourth electrode, i.e., the second auxiliary electrode, can be used to generate ionized water near and in contact with the working electrode. The ionized water can clean the working electrode to minimize effects due to scaling or biofilm formation. As such, the working electrode does not need the capability to clean itself. Thus, other elements, originally believed to be unsuitable for use in saline aqueous environments, can be used for the electrodes, for example, gold.

Abstract: The present invention concerns a method of measuring the concentration of an analyte in an aqueous solution that comprises the steps of: obtaining an aqueous solution containing an analyte, providing a cyanine indicator, placing the aqueous solution in fluid communication with the cyanine indicator, measuring a detectable property change of the cyanine indicator, and comparing the detectable property change of the cyanine indicator with a calibration curve of the detectable property change of samples containing known concentrations of the analyte to determine the concentration of the analyte, wherein the detectable property change is proportional to the concentration of the analyte in said aqueous solution.

Abstract: The invention relates to a device for measuring at least one physico-chemical parameter of water, said device including a means for measuring the concentration of active chlorine in the form of hypochlorous acid HOC1 in said water. According to the invention, said means for measuring the chlorine concentration in the form of hypochlorous acid HOC1 includes first (21) and second (22) amperometric sensors for detecting chlorine in the form of hypochlorous acid HOC1, each outputting a signal, said two amperometric chlorine sensors (21, 22) having a single common reference electrode (25) and being connected to a double potentiostat, characterised in that said invention includes a means for simultaneously implementing said first (21) and second (22) amperometric sensors, and in that said invention includes a means for measuring a difference between the signals output by said two sensors (21, 22).

Abstract: A electrochemical sensor comprising a mounting having screen printed array of electrodes located thereon, the array comprising a reference electrode, a counter electrode and a plurality of working electrodes, wherein the working electrodes are each overlaid with an insulating layer of insulating material, the insulating layer having an array of apertures, exposing a respective array of working regions of the working electrodes, and a method of making same by applying screen printing technic, and a method of using same for chlorine determination.

Abstract: The chloride concentration in an acid copper plating bath is determined from the chloride oxidation current measured under controlled hydrodynamic conditions at a noble metal electrode using specific voltammetric parameters. The measurement is made directly on the undiluted plating bath so that the chloride measurement is fast and no waste stream is generated.

Abstract: In order to provide a method of electrochemically detecting a target substance, a method of electrochemically detecting an analyte, and a detection set which have a theoretical advantage in the measurement sensitivity obtained by a conventional electrochemical detection method using a working electrode with a trapping substance immobilized, can reuse the working electrode, and can detect an analyte regardless of the size thereof, there is provided a method including: attracting the target substance containing a labeling substance in a liquid sample to a working electrode in which a trapping substance for trapping the target substance containing a labeling substance is not present; and electrochemically detecting the target substance containing a labeling substance.

Abstract: A method for determining a concentration of an analyte is disclosed. The method includes applying a potential excitation to a fluid sample containing an analyte and determining if a current decay curve associated with the fluid sample has entered an analyte depletion stage. The method also includes measuring a plurality of current values associated with the fluid sample during the analyte depletion stage and calculating an analyte concentration based on at least one of the plurality of current values.

Abstract: A process for the simultaneous determination of chlorine and chlorate in sodium hypochlorite. First and second streams of sodium hypochlorite are provided. The first stream is treated to generate iodine indicative of chlorine. The second stream is treated to generate iodine indicative of chlorine and chlorate. The iodine of the first stream is subjected to an amperometric measuring cell to generate a first current proportional to a chlorine concentration of the first stream. The iodine of the second stream is subjected to an amperometric measuring cell to generate a second current proportional to the chlorine and chlorate concentration in the second stream. The first current is subtracted from the second current to determine an amount of chlorate.

Abstract: A method for measuring an iodine adsorption number of carbon black includes: (a) electrochemically reducing an unknown amount of iodine adsorbed by a predetermined amount of a carbon black sample; (b) measuring the electrical charge used for reducing the unknown amount of the iodine adsorbed by the carbon black sample; and (c) obtaining the iodine adsorption number from the measured electrical charge. An electrolytic cell and a kit for measuring an iodine adsorption number of carbon black are also disclosed.

Abstract: Apparatus (2) for monitoring chlorine in water (4), which apparatus (2) comprises a flow cell (6), the flow cell (6) containing a chlorine sensor (62) and an automatic calibration system, and the automatic calibration system being such that it comprises a small pair of in-line electrodes (50) for generating low concentrations of free chlorine, and injection means (44) for injecting in use of the apparatus a salt solution (64) of known concentration.

Abstract: A device for monitoring chlorine in water, the device comprising a chlorine sensor adapted to measure a chlorine concentration in water; and a controller adapted to facilitate conversion between an active mode during which water analysis may be performed, and a low energy sleep mode in which the chlorine sensor is still energized but water analysis may not be performed. In sleep mode, a polarization voltage is maintained on an electrode comprised in chlorine sensor, which allows for a substantial reduction in a stabilization time required by the electrode following connection to an energy source after having been disconnected. Conversion between the active mode and the sleep mode may be according to predetermined parameter such as, for example, a predetermined time period, upon receipt of an indication from a independent timer, or by remote initiation from an external source.

Abstract: A electrochemical sensor comprising a mounting having screen printed array of electrodes located thereon, the array comprising a reference electrode, a counter electrode and a plurality of working electrodes, wherein the working electrodes are each overlaid with an insulating layer of insulating material, the insulating layer having an array of apertures, exposing a respective array of working regions of the working electrodes, and a method of making same by applying screen printing technic, and a method of using same for chlorine determination.

Abstract: A biosensor comprising a conducting polymer and a facilitating agent that combine to form a polymeric matrix that interacts with electrophilic compounds, wherein an electrochemical property of the polymer is altered in the presence of an electrophilic compound.

Abstract: Low concentrations of fluoride ion in a semiconductor processing solution containing an acid are determined via fluoride ion specific electrode measurements corrected for the effect of the acid concentration. No reagents are used for the fluoride determination.

Abstract: A sensor for measurement of free chlorine and of total chlorine in aqueous solution including a working electrode having a self-assembled monolayer (SAM) formed on the surface thereof, producing a barrier which reduces the generation of background currents when electrical potentials are applied to the electrode, and blocks the reduction or oxidation of interfering species in the solution, is described. Such SAMs have also been found to block the efficient reduction of chlorine as well. However, N,N-diethyl-p-phenylenediamine (DPD) has been found to effectively transport electrons across the SAM; that is, an oxidized form of DPD produced by a reaction with chlorine is capable of penetrating the SAM such that the reduction of the oxidized DPD species can occur. The generated reduction current is correlated with the concentration of chlorine in solution. Total chlorine may be determined by the addition of an iodide salt.

Abstract: A method of adjusting the output of an electrochemical sensor includes the steps of: simulating the presence of an analyte gas electronically; measuring a response of the sensor to the electronic simulation; and adjusting the output of the sensor as a function of the measured response to the electronic simulation. The method of adjusting the output of an electrochemical sensor having a working electrode and a counter electrode preferably includes the steps of: electronically causing a current flow between the working electrode and the counter electrode; measuring a response of the sensor to the current demand; and using the measured response to adjust the sensor output during sampling of an analyte gas.

Abstract: A sensor for measurement of free chlorine and of total chlorine in aqueous solution including a working electrode having a self-assembled monolayer (SAM) formed on the surface thereof, producing a barrier which reduces the generation of background currents when electrical potentials are applied to the electrode, and blocks the reduction or oxidation of interfering species in the solution, is described. Such SAMs have also been found to block the efficient reduction of chlorine as well. However, N,N-diethyl-p-phenylenediamine (DPD) has been found to effectively transport electrons across the SAM; that is, an oxidized form of DPD produced by a reaction with chlorine is capable of penetrating the SAM such that the reduction of the oxidized DPD species can occur. The generated reduction current is correlated with the concentration of chlorine in solution. Total chlorine may be determined by the addition of an iodide salt.

Abstract: The system concerns an electrode system for an electrochemical sensor, comprising, arranged on a conductive substrate (10), a plurality of micro-discs (22) electrically connected to the substrate and a generating electrode (20) insulated from the substrate by an insulating layer (14) and including a plurality of orifices (24) concentric with said micro-discs. A conductive layer (12) and connections (26, 28) enable to connect the electrodes to power sources. The generating electrode enables to modify locally, at the micro-discs, the concentrations of species present in solution opposite said electrodes.

Abstract: There is provided a sample preparation device and method for preparing a sample of liquid for detection of impurities. First (40) and second (38) electrodes are provided, located for immersion in a liquid under test. A semipermeable membrane (42) is positioned to protect the first electrode (40) from a body of liquid under test (32). The semipermeable membrane allows the liquid under test to pass therethrough to reach the first electrode, while preventing solids carried in the liquid from reaching the first electrode, the first electrode being positioned to affect the liquid under test in the vicinity of a sensor (36). Particular embodiments feature a hydrophilic membrane to protect the electrodes from suspended solids in the sample, a thin electrode assembly to achieve a faster response and the addition of a heater for temperature control to achieve consistent detection conditions and improved anti-fouling properties.

Abstract: A fluoride-sensitive electrode having a tubular electrode shaft, a lanthanum fluoride crystal, which closes the end of the electrode shaft, an internal electrolyte sealed between the lanthanum fluoride crystal and a closure in the electrode shaft, and a contact wire which dips into the internal electrolyte, wherein the internal electrolyte has a pH of ?9.0 and a fluoride concentration of ?0.1 M. The invention also includes the method of using the electrode to determine fluoride ion concentration.

Abstract: A simple analytical method for determining antioxidant level in food product and body fluids such as urine is based on reduction of elemental iodine. The method adds an aqueous solution of iodine and an iodophor to the sample to be tested. Polyvinylpyrrolidone is a preferred iodophor. Antioxidant materials in the sample reduce the elemental iodine and the reaction is monitored by measuring either a decrease in iodine or an increase in iodide ion. A preferred method of practicing the invention is to measure the change in iodide ion with an ion selective electrode and an appropriate electronic meter. The method rapidly and inexpensively produces antioxidant measurements that are comparable to those produced by my more complex and cumbersome methods.

Abstract: The invention relates to a method for determining an amount of a component in a mixture without calibration, including the steps of oxidizing a component of a mixture of gases to remove electrons from the mixture, measuring a current based upon the removed electrons, and determining an amount of molecules of the component present in the mixture based upon the measured current.

Abstract: A thick film electrochemical microsensor device for measuring or regulating chlorine and bromine in water, comprising a substrate to which is applied an optimum arrangement of at least two electrodes. The device is especially useful for measuring or regulating chlorine and bromine levels in swimming pool or spa water. A method of measuring or regulating ions of at least one of chlorine and bromine in water is also described, which comprises contacting the water with the microsensor of the present invention; measuring the current output of the microsensor; determining the level of at least one of chlorine and bromine indicated by the current output; and generating a signal.

Abstract: The concentration of chloride ion in an acid copper electroplating bath is determined from the effect that chloride exerts on the copper electrodeposition rate in the presence of organic additives. A cyclic voltammetric stripping (CVS) rate parameter is measured, before and after standard addition of a plating bath sample, in an acid copper electrodeposition solution containing little or no chloride and at least one organic additive. Cross contamination and waste disposal issues associated with the reagents and reaction products involved in chloride titration analyses are avoided. The method may also be applied to analysis of other halides (bromide and iodide) and other solutions.

Abstract: A fluoride-sensitive electrode having a tubular electrode shaft, a lanthanum fluoride crystal, which closes the end of the electrode shaft, an internal electrolyte sealed between the lanthanum fluoride crystal and a closure in the electrode shaft, and a contact wire which dips into the internal electrolyte, wherein the internal electrolyte has a pH of ≧9.0 and a fluoride concentration of ≧0.1 M. The invention also includes the method of using the electrode to determine fluoride ion concentration.

Abstract: A monitoring method and system to monitor an environment in which an object is located includes monitoring one or more environmental factors associated with corrosion of materials in the environment. Thereafter, an exposure index representative of cumulative exposure of the object to the one or more environmental factors is determined. For example, such environmental factors may include chloride ion concentration, pH level, humidity, and temperature.

Abstract: This invention is directed to a method and apparatus for controlling and optimizing the feed of two or more oxidizers to an aqueous stream, thereby providing a synergistic effect. The system combines the use of amperometric or ORP based sensor technology with amperometric sensor technology employing a gas permeable membrane, thereby providing definitive control of each oxidizer feed stream.

Abstract: A free fluoride ion sensitive electrode with longer service life can be obtained by eliminating the use of any cement or similar adhesive to hold the fluoride sensing crystal of the electrode in place within the rest of the structure of the electrode, using instead a pressure sealed combination of the fluoride sensing crystal and upper and lower elastomeric gaskets. This arrangement also permits replacing the crystal and sealing gaskets if needed, without replacing any of the other components of the electrode.

Abstract: The present invention relates to an electrochemical gaseous chlorine sensor. The sensor is characterized by covering one of the electrodes with a polymer material having a sensing activity and conductivity. The sensor includes: an ionic permeable film for separating a measuring chamber and a reference chamber, the ionic permeable film being a solid polymer electrolyte; a first electrode and a second electrode formed on two opposite sides of the ionic permeable film, the first electrode and the second electrode being conductors with catalytic activities; and a conductive polymer film formed on the first electrode. A fixed voltage ranging from −0.3 to 1.3V, preferably 0 to 0.2V, between said first electrode and said second electrode is maintained with a device, when the sensor is in use.

Abstract: This invention is directed to a method and apparatus for controlling and optimizing the feed of two or more oxidizers to an aqueous stream, thereby providing a synergistic effect. The system combines the use of amperometric or ORP based sensor technology with amperometric sensor technology employing a gas permeable membrane, thereby providing definitive control of each oxidizer feed stream.