Abstract: An embodiment provides a method for measuring nitrate in an aqueous sample, including: introducing an aqueous sample containing an amount of nitrate to a cation exchange resin; flowing the aqueous sample over copper metal; adding a reducing reagent to the aqueous sample; adding a colorimetric indicator to the aqueous sample; and measuring the amount of nitrate in the aqueous sample by measuring a change in intensity of the absorbance. Other aspects are described and claimed.

Abstract: An embodiment provides a method for measuring zinc and copper in an aqueous sample, including: reducing an aqueous sample containing an amount of zinc and an amount of copper with a reducing agent; buffering the reduced aqueous sample; chelating the amount of copper in the buffered aqueous sample with a copper(I) chelating agent; measuring the amount of copper in the aqueous sample by measuring a first change in intensity of the absorbance of the copper chelated aqueous sample; chelating the amount of zinc in the buffered aqueous sample with a zinc(II) chelating agent; and measuring the amount of zinc in the aqueous sample by measuring a second change in intensity of the absorbance of the zinc chelated aqueous sample. Other aspects are described and claimed.

Abstract: One embodiment provides a system, including: at least two water analyzers, wherein at least one of the at least two water analyzers is positioned upstream of a purification apparatus and wherein at least another of the at least two water analyzers is positioned downstream of the purification apparatus; at least one processor; and a memory device that stores instructions executable by the processor to: receive water analysis data from the at least two water analyzers, wherein the water analysis data comprises information related to membrane integrity; identify an algorithm for calculating membrane integrity based upon received data corresponding to system attributes; and calculate, using the identified algorithm, the membrane integrity based upon the received water analysis data. Other aspects are described and claimed.

Abstract: An embodiment provides a method for measuring total chlorine in a seawater sample, including: preparing a thiocarbamate-based indicator; introducing the thiocarbamate-based indicator to a seawater sample, wherein the seawater sample contains an amount of total chlorine; adding an additive to the seawater sample, wherein the additive accelerates the reaction rate between the thiocarbamate-based indicator and total chlorine and causes a change in fluorescence of the seawater sample; and measuring the amount of total chlorine in the seawater sample by measuring an intensity of the fluorescence. Other aspects are described and claimed.

Abstract: An embodiment provides a method for measuring total chlorine in a solution, including: preparing a thiocarbamate indicator; introducing the thiocarbamate indicator to a solution, wherein the solution contains an amount of monochloramine; adding an additive to the solution, wherein the additive accelerates the reaction rate between the thiocarbamate indicator and monochloramine and causes a change in fluorescence of the solution; and measuring the amount of monochloramine in the solution by measuring an intensity of the fluorescence. Other aspects are described and claimed.

Abstract: An embodiment provides a method for compensating for inteferants in measurement of alkalinity in a reagent-less system, including: introducing an aqueous sample into a measurement device comprising one or more series of electrodes; applying an electrical signal to the aqueous sample using the one or more series of electrodes, wherein the electrical signal is selected from the group consisting of: current and voltage; identifying, during application of the electrical signal, that the electrical signal reaches an oxidation threshold and measuring, prior to reaching the oxidation threshold, a first electrical response to the electrical signal, the first electrical response attributable to interferants in the aqueous sample; identifying, during application of the electrical signal, that the electrical signal reaches an endpoint and measuring, from the oxidation threshold to the endpoint, a second electrical response to the electrical signal; and measuring an alkalinity of the aqueous sample based upon a differenc

Abstract: An embodiment provides a method for real-time management of device maintenance utilizing quality metrics defined based upon inputs of the device, the method including: receiving inputs corresponding to a particular device, wherein the particular device provides measurements of a parameter of a fluid; generating, from the inputs, quality metrics for and unique to the particular device; monitoring the particular device while the particular device is deployed, wherein the monitoring occurs in view of the quality metrics; and triggering, responsive to detecting information corresponding to the particular device is violating at least one of the quality metrics, a notification to a user to perform an action corresponding to the particular device.

Abstract: An embodiment provides a self-lubricating linear peristaltic pump for delivering precise volumes of fluid, including: a housing comprising a slide area; at least one pinch block located within the slide area of the housing, wherein the at least one pinch block comprises a base end and a face end; a plurality of compression blocks located within the slide area of the housing, wherein each of the plurality of compression blocks comprises a base end and a face end; a cam located within the housing, wherein the mechanically contacts the base end of each of the at least one pinch block and the base end of each of the plurality of compression blocks; a motor mechanically coupled to the cam, wherein the motor moves the cam upon operation of the motor; and at least one tube in contact with the face end of each of the at least one pinch block and the face end of each of the plurality of compression blocks. Other aspects are described and claimed.

Abstract: An embodiment provides a method for measuring free chlorine in a solution, including: preparing a thiocarbamate-based indicator; introducing the thiocarbamate-based indicator to a solution, wherein the solution contains an amount of free chlorine and the introducing causes a change in fluorescence of the solution; and measuring the amount of free chlorine in the solution by measuring a change in intensity of the fluorescence. Other aspects are described and claimed.

Abstract: An embodiment provides a method for measuring sulfate in an aqueous sample, including: introducing an aqueous sample containing an amount of sulfate to a barium dye complex, thereby creating a solution; adding a clarifying agent to the solution, thereby causing the solution to be clarified; and measuring the amount of sulfate in the aqueous sample by measuring a change in color of the solution, the change in color caused by the barium dye complex mixing with the sulfate. Other aspects are described and claimed.

Abstract: An embodiment provides a device for mixing at least two reagent fluids, the mixed at least two reagent fluids being used for the measurement of a chemical attribute of a sample, including: a housing; at least two inlet ports, each to receive fluid in a premix state; an outlet port to dispense fluid in a postmix state; and a surface of a lumen for mixing, located within the housing, having a predetermined length, wherein the surface of the lumen is located between the at least two inlet ports and the outlet port, wherein the at least two inlet ports transition into the surface of the lumen, wherein the predetermined length is of a length allowing for sufficient mixing of the fluids received by the at least two inlet ports, wherein the surface of the lumen comprises at least one anti-siphoning element and a plurality of weirs to create a disturbance of a fluid contained therein, wherein the at least two fluids each comprise a reagent for a measurement of a chemical attribute of a sample.

Abstract: An embodiment provides A method for measuring fluoride concentration in an aqueous solution, including: preparing a metal-ligand complex, wherein the metal-ligand complex comprises chromeazurol S and aluminum; placing the metal-ligand complex in a sample containing fluoride, wherein the placing generates a color change by releasing the chromeazurol S from the metal-ligand complex; and measuring, using colorimetric techniques, a concentration of fluoride within the sample, wherein the measuring comprises measuring an absorbance wavelength of a colorimetric ligand. Other embodiments are described and claimed.

Abstract: An embodiment provides a method for measuring dissolved oxygen of an aqueous sample, including: introducing an aqueous sample into a measurement device comprising at least two dissolved oxygen sensors, wherein at least one of the at least two dissolved sensors comprises a trend sensor and at least another of the at least two dissolved sensors comprises a reference sensor; measuring a first value of dissolved oxygen using the trend sensor, wherein the trend sensor samples at a trend frequency; measuring a second value of dissolved oxygen from a reference sensor, wherein the reference sensor samples at a reference frequency, the reference frequency being less than the trend frequency; and correcting the first value of dissolved oxygen based upon the second value of dissolved oxygen. Other aspects are described and claimed.

Abstract: An embodiment provides a probe, including: an ion selective shell that includes a pH electrode bathed in an electrolyte and/or buffer solution; a plurality of conductive electrodes coaxially arranged respective to the pH electrode; the plurality of conductive electrodes being electrically isolated on a substrate displaced between the pH electrode and a reference electrode, and including: at least a first conductive electrode that is exposed to sample fluid at a terminal end of the probe proximate to the ion selective shell and disposed on the surface of an electrode substrate proximate to a terminal end of the reference electrode; and at least a second conductive electrode that is exposed to the sample fluid at the terminal end of the probe proximate to the ion selective shell and disposed on the surface of an el electrode substrate proximate to the terminal end of the reference electrode; the probe further including the reference electrode arranged about and along a longitudinal axis of the probe and bathed

Abstract: An embodiment provides a method for measuring sulfite in a solution, including: preparing a hemicyanine indicator; introducing the hemicyanine indicator to a solution containing an amount of sulfite, wherein the hemicyanine indicator reacts with the sulfite and causes a change in fluorescence of the solution; and measuring the amount of sulfite in the solution by measuring an intensity of the fluorescence. Other aspects are described and claimed.