Abstract: A real-time, on-line method and analytical system for determining halohydrocarbons in water which operate by (1) extracting on-line samples; (2) purging volatile halohydrocarbons from the water (e.g., with air or nitrogen); (3) carrying the purge gas containing the analytes of interest over a porous surface where the analytes are adsorbed; (4) recovering the analytes from the porous surface with heat (thermal desorption) or solvent (solvent elution) to drive the analytes into an organic chemical mixture; (5) generating an optical change (e.g., color change) in dependence upon a reaction involving the analytes and a pyridine derivative; and (6) measuring optical characteristics associated with the reaction to quantify the volatile halogenated hydrocarbon concentration.

Abstract: Systems and methods for separating organic chloramines and inorganic chloramines from an aqueous solution. Such a method includes providing a first container containing an aqueous solution that includes organic and inorganic chloramines and free chlorine, providing a second container containing a trapping solution and a tubular hydrophobic membrane through which inorganic chloramines contained in the aqueous solution can diffuse into the trapping solution, pumping the aqueous solution from the first container through the tubular hydrophobic membrane of the second container; and collecting the aqueous solution pumped through the tubular hydrophobic membrane in a third container connected to the tubular hydrophobic membrane. After pumping is completed, the second container contains an aqueous solution containing the inorganic chloramines and the third container contains an aqueous solution containing the organic chloramines and the free chlorine.

Abstract: A real-time, on-line method and analytical system for determining halohydrocarbons in water which operate by (1) extracting on-line samples; (2) purging volatile halohydrocarbons from the water (e.g., with air or nitrogen); (3) carrying the purge gas containing the analytes of interest over a porous surface where the analytes are adsorbed; (4) recovering the analytes from the porous surface with heat (thermal desorption) or solvent (solvent elution) to drive the analytes into an organic chemical mixture; (5) generating an optical change (e.g., color change) in dependence upon a reaction involving the analytes and a pyridine derivative; and (6) measuring optical characteristics associated with the reaction to quantify the volatile halogenated hydrocarbon concentration.

Abstract: There is provided plate equipped with a mechanism to facilitate determination of the amount of a fluid added to or removed from a well in the plate. Other embodiments are also described.

Abstract: The present invention provides a carboxylate-bridged binuclear iron-sulfur clusters fluorescent probe having the structure of Formula I. The preparation method comprises the following steps: anthracenylmethanamine and p-methoxycarbonylphenyl isocyanate have an addition reaction to get a substitutional methyl benzoate, which is hydrolyzed to get a corresponding carboxylic acid; react the resulting carboxylic acid with alkali to get carboxylate, and then coordinate with binuclear iron precursor to obtain the fluorescent probe. Compared with the prior art, the invention firstly provides the carboxylate-bridged binuclear iron-sulfur clusters of metal complex which similar to the central structure of bio-enzyme. The metal complex, as a fluorescent probe, has good selectivity to the fluorinion detection. The fluorescence titration experiment is simple and easy to operate and the fluorescence changes are sensitive.

Abstract: A real-time method and analytical system for determining haloacetic acids in water which operate by: (1) extracting samples on ion-exchange absorbent medium; (2) concentrating haloacetic acids on hyper-crosslinked medium; (3) eluting the analytes from the concentration medium for injection into an HPLC system; (4) separating individual haloacetic acid in reverse-phase chromatography performed by the HPLC system; and (5) measuring optical characteristics (UV-absorbance) of haloacetic acids, to determine concentration. The entire process can be performed using a completely self-contained, in-situ mechanism that sits at a water distribution point for 24/7 testing, with automated control, monitoring, reporting, and employment of remedial measures (e.g., automated adjustment of the water treatment process).

Abstract: A test element (10) used to determine concentration levels of free and total chlorine in a water sample comprises a test pad (12) adhered to a substrate (14), wherein the test pad (12) is impregnated with a stabilized DPD solution. The test pad (12) is color responsive to different concentration levels of chlorine in the water and compared to a color chart to determine the level of free chlorine and/or total chlorine in the water. The stabilized DPD solution may include N,N-diethyl-p-phenylenediamine oxalate salt, a polymeric anhydride such as a methyl-vinyl anhydride and an organo-sulfate such as dimethylsulfone.

Abstract: Methods and systems to determine a concentration of bromide ions in an aqueous sample are disclosed. The method involves the oxidation of bromide ions to bromine, followed by bromination of a colored or fluorescent reporter compound which may be detected by spectrophotometric means. The relative change in color or fluorescence upon bromine binding to the reporter compound may then be used to determine a quantitative concentration of bromide ions in the sample. The system utilizes a photocatalytic coating in a sample chamber, a source of reporter compound in fluid communication with the sample chamber, light sources that may activate the photocatalyst and excite the reporter compound, an optical detection unit capable of receiving a light signal from the second light source after it has passed through the sample chamber, and various pumps, valves or injection syringes that regulate the flow of sample and reporter compound into and out of the sample chamber.

Abstract: The invention is directed towards methods and apparatus for accurately detecting the presence and concentration of an oxidant in a turbid water sample. This method is very helpful in allowing accurate and efficient (not too much nor too little) amounts of microbe killing oxidants to be introduced to water supplies that require oxidants but which at present cannot be measured properly. The method comprises the steps of: passing the water through at least one filter array, passing the filtered water to an analyzer, and then returning from the analyzer a measurement of the concentration. The filter array comprises at least one filter constructed and arranged to remove turbidity inducing material but not oxidant from the water sample. The analyzer can be a commonly commercially available analyzer that currently cannot accurately measure the oxidant concentration if the water had not been so filtered.

Abstract: A data processing system and a computer program product for monitoring water consumption. A set of locations in a fluid transport system in a structure is monitored for sounds generated by a fluid flowing at an endpoint of the fluid transport system. Current acoustic data is generated for the sounds detected from monitoring the set of locations. The current acoustic data is compared with historical acoustic data to form a difference. A determination is made as to whether the difference exceeds a threshold. An action is performed in response to determining that the difference exceeds the threshold.

Abstract: Provided is a heat dried reagent composition that is dry, methods of making it, and methods of using it. The heat dried reagent composition can be characterized by one or more of: stability to the heat drying conditions; storage stability of the heat dried reagent composition; fast rehydration time; rapid assay kinetics; and assay precision. The reagent composition is useful for detecting and/or assessing total chlorine in an aqueous sample, such as pool water.

Abstract: Provided is a heat dried reagent composition that is dry, methods of making it, and methods of using it. The heat dried reagent composition can be characterized by one or more of stability to the heat drying conditions; storage stability of the heat dried reagent composition; fast rehydration time; rapid assay kinetics; and assay precision. The reagent composition is useful detecting and/or assessing free chlorine in an aqueous sample, such as pool water.

Abstract: An analytical test cartridge is provided. The analytical test cartridge can be used for medical analyses of liquid samples removed from a patient, for example blood. The analytical test cartridge is configured to provide for titration experiments. An example of a titration experiment that can be performed with the arrangement, is titration of heparin with protamine. Methods of assembly and use are provided.

Abstract: Constant calibration methods and apparatuses for analytical devices that are located in remote positions in order to allow for reliable and automated measurements of various contaminants within water or other liquid samples. The proposed calibration systems allow for certain methods to measure total amounts of certain trihalomethane and haloacetic acid contaminants, at least, in drinking water samples from such remote locations, through the utilization of a standard addition introduction of known concentrations of such contaminant compounds within target samples, followed by separation through a capillary membrane sampling device and measurement of such different contaminants via flow injection analysis (FIA). In such a manner, the on-line, remote system provides the necessary reliability for a water utility or like entity on which to base any further needed water treatment activities without having to perform such measurements in a distinct lab setting.

Abstract: A test element (10) used to determine concentration levels of free and total chlorine in a water sample comprises a test pad (12) adhered to a substrate (14), wherein the test pad (12) is impregnated with a stabilized DPD solution. The test pad (12) is color responsive to different concentration levels of chlorine in the water and compared to a color chart to determine the level of free chlorine and/or total chlorine in the water. The stabilized DPD solution may include N,N-diethyl-p-phenylenediamine oxalate salt, a polymeric anhydride such as a methyl-vinyl anhydride and an organo-sulfate such as dimethyisulfone.

Abstract: Methods and apparatus are disclosed for an improved water chemistry test. Features disclosed include, without limitation, a test block, colored liquid reagents, and color comparison displays, with test chambers/vials that are generally horizontal. The mouth at the top of each vial is formed along a substantial portion of the vial's horizontal length. The vial's horizontal dimensions enable water to move throughout each vial so that a wave or waves roll from one side of the vial to the other and quickly/thoroughly mixes colored liquid reagents with sample water. At least one ridge, wall, semipermeable barrier, etc. within the vial causes water and chemical reagents to more quickly and thoroughly when the test block is agitated. At least one drain hole is positioned in a wall/side of each vial, with its bottom edge located at the fill level necessary to conduct the water sample. A valve or valves enables a user to easily drain sample water from the vial down to the proper test level.

Abstract: Provided is a method for evaluating of the chemical stability of a polychloroprene latex that permits evaluation of the chemical stability of polychloroprene at high accuracy. First, an aqueous calcium hydroxide or calcium nitrate solution at a concentration of 0.05 to 0.40 mass % is added to a polychloroprene latex having a solid matter concentration of 45 to 65 mass %. The generated precipitate is then collected by filtration and the dry mass is determined, and the precipitation rate (%) is calculated according to the following Formula (I). Precipitation ? ? rate ? ? ( % ) = A { B × ( C ? / ? 100 ) } × 100 ( I ) (wherein, A represents the dry mass (g) of the precipitate; B represents the mass (g) of the polychloroprene latex, and C represents the solid matter concentration (mass %) of the polychloroprene latex.

Abstract: Provided is a heat dried reagent composition that is dry, methods of making it, and methods of using it. The heat dried reagent composition can be characterized by one or more of stability to the heat drying conditions; storage stability of the heat dried reagent composition; fast rehydration time; rapid assay kinetics; and assay precision. The reagent composition is useful detecting and/or assessing free chlorine in an aqueous sample, such as pool water.

Abstract: Provided is a heat dried reagent composition that is dry, methods of making it, and methods of using it. The heat dried reagent composition can be characterized by one or more of: stability to the heat drying conditions; storage stability of the heat dried reagent composition; fast rehydration time; rapid assay kinetics; and assay precision. The reagent composition is useful for detecting and/or assessing total chlorine in an aqueous sample, such as pool water.

Abstract: An aquatic environment monitoring system and method that includes correction for adverse conditions in the monitoring system involving the development of confidence levels for certain conditions in the monitoring system using stored information related to the aquatic environment and/or the monitoring system. Corrections to adverse conditions may be made by the environment monitoring system automatically by the monitoring system and manually via communications to a user of the system.

Abstract: A detection method using colorimetric analysis of the present invention includes: providing a first solution in which two materials selected from metal nanoparticles, an oxidizing agent, and chloride ions are mixed; providing a second solution including one other material that is not included in the first solution among the metal nanoparticles, the oxidizing agent, and the chloride ions; preparing a mixture solution by mixing the first solution and the second solution; and testing and measuring a color change of the mixture solution.

Abstract: The invention relates to a method of monitoring a concentration of a halogenated disinfectant in swimming pools or the like and a device for implementing the method. The method comprises: a liquid-injection step of injecting the liquid to be analyzed into the analysis chamber; a reagent-injection step of injecting a reagent into the analysis chamber; a measurement step of measuring the liquid/reagent mixture by colorimetry; a processing step of processing the measurement in relation to data; and a verification step of verifying the colorimetric measurement when the measurement corresponds to the reagent being bleached or to an absence of reaction color.

Abstract: A method for measuring bromate ion is provided that provides high-sensitivity measurement results more simply and more quickly than conventional bromate ion measurement methods. A fluorescent substance that is quenched by coexistence with bromate ions is added to a sample 130 and the fluorescence intensity of the fluorescent substance after quenching is measured, the measured fluorescence intensity being subtracted from the fluorescence intensity of a standard sample containing no bromate ions to calculated the fluorescence intensity difference. The bromate ion concentration is calculated from the calculated fluorescence intensity difference, using a pre-determined calibration line between the fluorescence intensity difference and the bromate ion concentration.

Abstract: A disposable cartridge adapted to be used with a sensor-dispensing instrument comprises a housing, test sensors, a mechanical mechanism and moveable seals. The housing forms at least one opening therethrough. The test sensors are stacked in the housing. The test sensors are adapted to assist in testing at least one analyte. The mechanical mechanism is adapted to urge the test sensors in a first direction. One of the test sensors is positioned for ejection from the cartridge. The moveable seals is adapted to be in a closed position that seals the at least one opening so as to provide a substantially moisture-proof and a substantially air-tight cartridge, and one of the moveable seals is adapted to be in an open position that allows one of the test sensors to be moved therethrough.

Abstract: A system and method for determining a concentration of total chlorine in dialysis water are provided. The system comprises a main unit housing a KI/water sample chamber and a sodium sulfate chamber. A first electrode pair bridges the two chambers and generates tri-iodide proportional to the amount of total chlorine in the water sample. A second electrode pair in contact with fluid in the KI/water sample detects an amount of tri-iodide generated by the first electrode pair. The system is suitable for use in connection with, or for incorporation into, a water purification system for generating dialysis fluid, and may include a display that alerts the user to stop or prevent a hemodialysis treatment if the total chlorine level exceeds a predetermined level.

Abstract: Techniques related to printing using a metal-surface charging element. A printing system includes a metal-surface charging element and a power supply. The charging element is disposed to deposit electric charge on an imaging surface. The power supply may provide electric power with an alternating current (AC) component and a direct current (DC) component to the charging element.

Abstract: Methods and systems to determine a concentration of bromide ions in an aqueous sample are disclosed. The method involves the oxidation of bromide ions to bromine, followed by bromination of a colored or fluorescent reporter compound which may be detected by spectrophotometric means. The relative change in color or fluorescence upon bromine binding to the reporter compound may then be used to determine a quantitative concentration of bromide ions in the sample. The system utilizes a photocatalytic coating in a sample chamber, a source of reporter compound in fluid communication with the sample chamber, light sources that may activate the photocatalyst and excite the reporter compound, an optical detection unit capable of receiving a light signal from the second light source after it has passed through the sample chamber, and various pumps, valves or injection syringes that regulate the flow of sample and reporter compound into and out of the sample chamber.

Abstract: One or more natural resources (e.g., bodies of water, volumes of air or earth, mineral deposits, or wildlife populations) may be tracked by one or more natural resource quality sensors, each of which may detect and report various natural resource quality indicators (e.g., indicators of purity, biological or chemical contaminants, physical properties, and indicators of various components of a processing facility managing the natural resource, such as a water supply system). These indicators may be reported to one or more natural resource servers, which may store the indicators and, upon request of one or more users, generate a natural resource quality report indicating the quality of various natural resources. Reports may also be generated spontaneously and delivered as an alert based upon alert criteria (e.g., upon detecting a water height in a river correlated with flooding, a natural resource server may notify users residing near the river).

Abstract: Provided is a method for evaluating of the chemical stability of a polychloroprene latex that permits evaluation of the chemical stability of polychloroprene at high accuracy. First, an aqueous calcium hydroxide or calcium nitrate solution at a concentration of 0.05 to 0.40 mass % is added to a polychloroprene latex having a solid matter concentration of 45 to 65 mass %. The generated precipitate is then collected by filtration and the dry mass is determined, and the precipitation rate (%) is calculated according to the following Formula (I). Precipitation ? ? rate ? ? ( % ) = A { B × ( C ? / ? 100 ) } × 100 ( I ) (wherein, A represents the dry mass (g) of the precipitate; B represents the mass (g) of the polychloroprene latex, and C represents the solid matter concentration (mass %) of the polychloroprene latex.

Abstract: A disposable cartridge adapted to be used with a sensor-dispensing instrument comprises a housing, test sensors, a mechanical mechanism and moveable seals. The housing forms at least one opening therethrough. The test sensors are stacked in the housing. The test sensors are adapted to assist in testing at least one analyte. The mechanical mechanism is adapted to urge the test sensors in a first direction. One of the test sensors is positioned for ejection from the cartridge. The moveable seals is adapted to be in a closed position that seals the at least one opening so as to provide a substantially moisture-proof and a substantially air-tight cartridge, and one of the moveable seals is adapted to be in an open position that allows one of the test sensors to be moved therethrough.

Abstract: It is a subject of the present invention to provide a novel polymer; a filler for measuring a perfluoro compound having an acidic group at terminal which comprises said polymer; a column filled with said filler; and a measuring method for a perfluoro compound having an acidic group at terminal by using said column; as well as a filler for measuring a drug comprising the above-described polymer; a column filled with said filler; and a measuring method for a drug by using said column.

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: Quaternary nitrogen heterocyclic boronic acid-containing compounds are described, which are sensitive to glucose and fructose, as well as a variety of other physiologically important analytes, such as aqueous chloride and iodide, and a method of using the compounds. Also disclosed is a contact lens doped with the quaternary nitrogen heterocyclic boronic acid-containing compound, and a method of using the doped contact lens to measure the concentration of analyte in tears under physiological conditions.

Abstract: Congeneric, halogenated, fluorinated aromatic compounds A and B are each phenyl radicals, L=oxygen atom, sulfur atom or alkylene radical and p=0 or 1; processes for their preparation and their use.

Abstract: A multi-purpose reagent composition is used for simultaneously determining concentrations of at least two analytes in a water sample. The two analytes are selected from the group consisting of free chlorine, pH, anionic polymer, and phosphates. In one embodiment, the multi-purpose reagent composition is for simultaneously determining the concentration of free chlorine and pH and comprises a free chlorine sensitive dye and pH indicator. In another embodiment, the reagent composition is for simultaneously determining of free chlorine and anionic polymer and includes a free chlorine sensitive dye, a pH buffer, cationic dye, and organic co-solvent. Thus, the pairs of free chlorine and pH or free chlorine and anionic polymer are determined using a single reagent composition. The reagent composition can also be the main reagent for one analyte analysis when it is used alone and also function as an ancillary reagent when it is combined with a second reagent composition for the determination of another analyte.

Abstract: A water quality analyzer comprises: sensor electrodes 1a, 1b made of different metals from each other, the electrodes in a liquid of inspecting object generating a sense voltage in proportion to the liquid's impurities concentration; an operational amplifier OP1 amplifying the sense voltage without inverting to provide for a CPU 3; a resistor R0 whose one end is connected to the electrode 1a; and a voltage divider 2 applying a voltage obtained by dividing the sense voltage by a prescribed division ratio to R0's another end. The CPU 3 calculates input signal from OP1 to obtain chlorine concentration and displays the calculated result on a LCD 4 in a measurement mode, and sets the division ratio of the divider 2 so that sense voltage across electrodes 1a, 1b soaked in a liquid including prescribed concentration chloride approximately agrees with a reference voltage of prescribed concentration in a sense-voltage calibration mode.

Abstract: A real-time, on-line method and analytical system for determining halohydrocarbons in water which operate by (1) extracting on-line samples; (2) purging volatile halohydrocarbons from the water (e.g., with air or nitrogen); (3) carrying the purge gas containing the analytes of interest over a porous surface where the analytes are adsorbed; (4) recovering the analytes from the porous surface with heat (thermal desorption) or solvent (solvent elution) to drive the analytes into an organic chemical mixture; (5) generating an optical change (e.g., color change) in dependence upon a reaction involving the analytes and a pyridine derivative; and (6) measuring optical characteristics associated with the reaction to quantify the volatile halogenated hydrocarbon concentration.

Abstract: A system for sensing and communicating in a pipeline that contains a fluid. An acoustic signal containing information about a property of the fluid is produced in the pipeline. The signal is transmitted through the pipeline. The signal is received with the information and used by a control.

Abstract: A chemical indicating device (10) for detection of chloride ions in a sample is provided. The chemical indicating device (10) includes a carrier matrix (12) and an indicator (14) having silver and vanadate supported on the carrier matrix (12).

Abstract: Disclosed is a method for controlling microbial growth in an aqueous system containing sulfite and/or bisulfite residues by addition of a peroxy compound at a pH of grater than 5. Also disclosed is a method for stabilizing an active halogen biocide in an aqueous system containing peroxide residues by addition of an N-hydrogen compound to the active halogen biocide before combining it with the peroxide containing aqueous system. Further disclosed is an optimized papermaking biocide program consisting of initially treating sulfite bleached pulp with peroxide followed by application of an N-hydrogen-stabilized active halogen compound to the paper producing white waters and an analytical method for determining peroxide concentrations in aqueous systems in the presence of sulfite and/or bisulfite.

Abstract: A measurement system is provided which comprises an analysis device with at least one of a measurement function and a sample collection function, and also at least one magazine configured to receive at least one consumer element therein. The magazine comprises a magazine housing having a pair of openings. The magazine is designed as an exchangeable magazine that can be selectively operatively connected to the analysis device. The analysis device further comprises a closure mechanism having at least one sealing element which is designed to convey at least one consumer element from one of the openings. The sealing element is further configured to sealingly close the openings of the magazine when the sealing element is disposed therein.

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 provides a method and apparatus for determining the amount of various materials in a liquid sample. Because the apparatus is particularly resilient it can be used repeatedly with very harsh liquid samples such as boot water from an oil refinery. The apparatus uses at least one volume and/or concentration independent optical analysis method to determine at least one of: the pH, amount of chloride, and/or amount of iron in the sample. The optical property can be colorimetric, fluorescent or both and result from adding dyes, complexing agents, turbidity inducing compounds, and other optically effecting reagents to the sample. Because the measurements are concentration and volume independent they can be done continuously, quickly, and avoid the inconvenient start and stop procedures in prior art measurement regimens.

Abstract: Naturally present chloride concentration in natural water is utilized for the development of the technique to gauge the performance of percolation tanks in space and time. The chloride mass balance technique is simple, sensitive, reliable and yet powerful enough to resolve the temporal variation due to the effect of silting or climate factors. The percolation efficiency data of percolation tanks can aid in the formulation of guidelines for selection of suitable sites for future tanks with greater efficiency. Otherwise unscientific construction of percolation tanks in sites that yield poor percolation efficiency is uneconomical, and the very purpose of their construction will be forfeited. Thus the technique developed using chloride mass balance in tank water for evaluation of tank performance is highly economy oriented.

Abstract: The present invention relates to a chemical reagent for measuring the halogen-agent content, in particular in swimming pool water, and also to an associated measurement method, and such that the chemical reagent, according to the invention, comprises a polysaccharide, an acid stabilizer compound, potassium iodide, a dye, and distilled water.

Abstract: An apparatus for measuring optimum water-quality and informing quality of water 100 measures an amount of impurities of water, keeps to renew an optimum value by a lowest amount of the impurities until the present use, compares the optimum value with the present amount of the impurities measured in the water and informs the result.

Abstract: A disposable cartridge adapted to be used with a sensor-dispensing instrument comprises a housing, test sensors, a mechanical mechanism and moveable seals. The housing forms at least one opening therethrough. The test sensors are stacked in the housing. The test sensors are adapted to assist in testing at least one analyte. The mechanical mechanism is adapted to urge the test sensors in a first direction. One of the test sensors is positioned for ejection from the cartridge. The moveable seals is adapted to be in a closed position that seals the at least one opening so as to provide a substantially moisture-proof and a substantially air-tight cartridge, and one of the moveable seals is adapted to be in an open position that allows one of the test sensors to be moved therethrough.

Abstract: A compound represented by the following general formula (II): wherein R21 represents hydrogen atom or one to four monovalent substituents substituting on the benzene ring, and when R21 represents two or more substituents, the substituents may be the same or different; R22, R24, R25, and R27 independently represent hydrogen atom, or a monovalent substituent; R23 represents —OH or —N(R28)(R29) (wherein R28 and R29 independently represent an alkyl group which may be substituted); R26 represents —N(R30)(R31) (wherein R30 and R31 independently represent an alkyl group which may be substituted); n represents an integer of 1 to 3; and Y represents —S— or —O—, which is useful for selective measurement of hypochlorite ion.

Abstract: A chemical indicating device (10) for detection of chloride ions in a sample is provided. The chemical indicating device (10) includes a carrier matrix (12) and an indicator (14) having silver and vanadate supported on the carrier matrix (12). A method for detecting chloride ions is also provided.

Abstract: The present invention describes methods and kits for determining the concentration of free chlorine in water. To avoid false readings from other species present in the water, the free chlorine is reacted with ammonia to form monochloramine, which is then reacted to form an indophenol or an indonaphthol. The concentration of the indophenol or indonaphthol is proportional to the total monochloramine present. Subtracting the concentration of residual monochloramine from the total monochloramine yields the concentration of monochloramine formed from the free chlorine and ammonia, and is proportional to the concentration of free chlorine. Embodiments of the present invention will simplify and accelerate accurate measurements of free chlorine in water, without interference from compounds impacting present measurements of free chlorine.