Abstract: There is provided an apparatus for detecting sodium in a liquid. A concentration of a very small amount of sodium can be repeatedly and accurately measured by correcting baseline fluctuation and sodium concentration variation due to temperature variation on the basis of measured temperature and minimizing noise influence on the concentration measurement. According to the apparatus for detecting sodium in a liquid, the apparatus for detecting sodium in a liquid can accurately and repeatedly measure a concentration of a very small amount of sodium by minimizing noise and temperature variation effects on concentration measurements to ensure measurement accuracy of sodium concentration and the stability of a baseline as a measurement reference.

Abstract: An electrochemical polymerization based salt content analyzer configured to determine salt composition in a direct, fast, and serial manner. The salt content analyzer includes three electrodes: a working electrode, a counter electrode and a reference electrode. In operation, the current passing through the electrodes as a sweeping voltage is applied may be analyzed to determine the salt content of the analyte. When a voltage is applied, an electro-polymerizable monomer forms a thin film on the working electrode. The working electrode includes an access control mechanism to only expose a fraction of the working length of the working electrode to the outside environment at any given time. The access control mechanism is advanced between tests to expose a fresh portion of the working electrode and conceal the portion with a thin film of electro-polymerized monomer. Thus, testing may be performed in a serial manner.

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: 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: This invention relates to a correction liquid for a liquid membrane type ion-selective electrode that makes it possible to measure a ratio between a sodium ion concentration and a potassium ion concentration in urine by correcting for an influence from an ionic strength of the urine. The correction liquid comprises a sodium ion-sensitive part that selectively reacts with the sodium ion and a potassium ion-sensitive part that selectively reacts with the potassium ion, and measures a ratio between a sodium ion concentration and a potassium ion concentration in urine, and comprises the sodium ion, the potassium ion, and an electrolytic ionic strength modifier.

Abstract: A sodium sensor to measure a concentration of sodium methylate in methanol. The sensor assembly includes a solid alkali ion conducting membrane, a reference electrode, and a measurement electrode. The solid alkali ion conducting membrane transports ions between two alkali-containing solutions, including an aqueous solution and a non-aqueous solution. The reference electrode is at least partially within an alkali halide solution of a known alkali concentration on a first side of the solid alkali ion conducting membrane. The measurement electrode is on a second side of the solid alkali ion conducting membrane. The measurement electrode exhibits a measurable electrical characteristic corresponding to a measured alkali concentration within the non-aqueous solution, to which the measurement electrode is exposed.

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 sodium sensor to measure a concentration of sodium methylate in methanol. The sensor assembly includes a solid alkali ion conducting membrane, a reference electrode, and a measurement electrode. The solid alkali ion conducting membrane transports ions between two alkali-containing solutions, including an aqueous solution and a non-aqueous solution. The reference electrode is at least partially within an alkali halide solution of a known alkali concentration on a first side of the solid alkali ion conducting membrane. The measurement electrode is on a second side of the solid alkali ion conducting membrane. The measurement electrode exhibits a measurable electrical characteristic corresponding to a measured alkali concentration within the non-aqueous solution, to which the measurement electrode is exposed.

Abstract: The invention relates to a lithium ion-selective membrane, including a polymer carrier, a plasticizer, a conductive compound and a lithium ion specific ionophoric compound. The invention consists in that said ionophoric compound is dibenzyl-14-crown-4 and derivatives thereof, and represents between 0.5 and 3% by weight of the total composition of the membrane, the polymer carrier representing 25 to 30% by weight of the total composition of the membrane, the plasticizer from 65 to 72% by weight of the total composition of the membrane and the conductive compound from 0.2 to 1.5% by weight of the total composition of the membrane. Said invention can be used to determine the lithium ion concentration of a fluid, such as a primary fluid for a pressurized water reactor in a nuclear power plant.

Abstract: Disclosed is a method of in-situ monitoring a reduction process of uranium oxides by lithium metal, wherein a conversion yield of uranium metal from uranium oxides upon production of uranium metal through a reaction of uranium oxides (UOx, x?3) with lithium metal in the presence of a high-temperature molten salt is measured according to an electrochemical analysis based on an oxidation of an oxygen ion and a reduction of a lithium ion dissociated from lithium oxide obtained as a by-product of the reaction, by use of a measuring device composed of a potentiostat/galvanostat and a reactor provided with an anode and a cathode. The in-situ monitoring method of the current invention is advantageous in terms of fast and simplified measuring techniques, by directly measuring the reduction process of uranium oxides at the anode and cathode connected to the potentiostat/galvanostat in the presence of the high-temperature molten salt.

Abstract: The present invention relates to an electrochemical sensor for determining the concentration of a group IA metal in a fluid such as molten metal. The sensor comprises a substantially pure quantity of the group 1A metal as a reference electrode (13) contained in a sensor housing (3), and a solid electrolyte constituting at least part of the sensor housing (3). The electrolyte is in electrical contact with the reference electrode (13) and the sensor is capable of operating at temperatures in excess of 973K. In a preferred arrangement, the sensor comprises a two part elongate conductor (15), a first part (17) of which extends from the reference electrode (13) into a refractory seal (11a), and a second part (19) of which extends from within the refractory seal (11a) externally of the sensor, the two parts (17, 19) being welded together.

Abstract: Plasticizer-free ion-detecting sensors for detecting a target ion in a sample are provided. The sensor comprises a plasticizer-free copolymer comprised of polymerized units of methacrylate monomers and a polymerizable ion exchanger, wherein the methacrylated monomers have pendent alkyl groups of different length and wherein the functionalized ion-exchanger is grafted into the copolymer through covalent linkages. The ion exchanger comprises a C-derivative of a halogenated closo-dodecacarborane anion having a polymerizable moiety. Sensors of this invention include carrier-based ion-selective electrodes or optodes such as thin film ion-specific optodes, particle-based optodes, or bulk optodes.

Abstract: A plasticizer-free ion detective sensor for detecting a target ion in a sample is provided. The sensor comprises a copolymer of methacrylate monomers with pendant alkyl groups of different length, and an ionophore for detecting the target ion. The copolymer matrix of the present invention may be in a form of membrane or particles. The sensors of the present invention may be Carrier-based ion-selective electrodes (ISEs) or optodes such as thin film ion-specific optodes or particle-based optodes. The ionophore may be a target ionophore selective for a target ion H+, Li+, Na+, K+, Ca2+, or Mg2+. The ion detective sensor of the present invention may further include an ion exchanger such as halogenated carboranes. Also provided is an ion detective sensor comprising halogenated carboranes as ion exchangers. Particularly, trimethylammonium-2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 undecabromocarborane (TMAUBC) is used as ion exchangers.

Abstract: Ion-detecting sensors for detecting a target ion in a sample are provided. The sensor comprises a plasticizer-free copolymer comprised of polymerized units of methacrylate monomers having pendent alkyl groups of different length and a functionalized ionophore of said ion, wherein at least a portion of the functionalized ionophore is grafted into the copolymer through covalent linkages. Sensors may comprise ionophores such as hydrophilic crown ethers or functionalized derivative of 3-oxapentandiaminde-type ionophores. This invention further provides sensors for detecting target ions in a sample, comprising plasticizer-free molecularly imprinted polymers, wherein the polymers comprise polymerized units of methacrylate monomers having pendent alkyl groups of different length and a functionalized ionophore of said ion. In particular, a magnesium ion sensor comprising a functionalized derivative of a 3-oxapentandiaminde-type calcium ion-selective ionophore is provided.

Abstract: A method for reducing interference caused by contaminants on the detection and/or measurement of an analyte in a biological sample includes providing a chemical sensor that contains carboxylated polyvinyl chloride (PVC—COOH) as a polymer component of the sensor's polymeric membrane. A biological sample containing the analyte of interest and a contaminant is placed in contact with the chemical sensor that includes PVC—COOH as a polymer component of the sensor's polymeric membrane. The analyte of interest in the biological sample is then measured and/or detected by the chemical sensor without interference by the contaminant.

Abstract: A method and apparatus for measuring a target constituent of an electroplating solution using an electroanalytical technique is set forth. In accordance with the method, at least two electrodes are employed to execute the electroanalytical technique. Gasses that are trapped or generated at the surface of one or both of the electrodes of the pair are reduced and/or removed by directing a flow of solution toward the electrode surface. This flow of solution against the electrode surface acts to automatically flush the generated gasses (typically in the form of small bubbles) from the electrode surface and generally eliminates the need for manual purging by an operator. Elimination of these gasses reduces or eliminates variability in the open circuit potential, and concomitant noise that would otherwise occur in the electroanalytical measurements.

Abstract: Improved dry-operative ion-selective electrodes and their use are described. The dry-operative ion-selective electrodes include an internal reference electrode comprising a water-soluble salt dispersed in a polymer binder consisting essentially of a monomer having at least one carboxyl group and a hydrophobic monomer. The polymer provides reduced brittleness, good interlayer adhesion and high salt tolerance.

Abstract: An electrochemical process is provided for treatment of molten kraft smelt produced from black liquor in a kraft recovery boiler. Treated smelt can be contacted with water to produce white liquor which can be re-used or recycled in the kraft process.