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.

A process of utilizing a water-sensitive fluorophore for moisture content evaluation in a hygroscopic polymer includes forming a blend that includes a hygroscopic polymer resin and a water-sensitive fluorophore. The process includes forming pellets having a particular geometry from the blend, determining fluorescence properties of at least one of the pellets, and determining moisture content of at least one of the pellets. The process also includes generating a calibration curve for the particular pellet geometry by correlating the fluorescence properties with the moisture content. The process further includes providing the calibration curve for non-destructive moisture content evaluation of a material derived from the pellets.

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.

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.

Systems and methods for sensing and measuring local pH, pOH, and other protonic species using reversible excited-state photoacids and photobases are described. Various reversible excited-state photoacids and/or photobases are described that through a dynamic sensing mechanism exhibit varied fluorescence or phosphorescence intensity based on local activity of protonic species. Photoacids and photobases can be used in combination with confocal fluorescent microscopy for quantifying local activity of protonic species.

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.

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.

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.

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.

A process of utilizing a water-sensitive fluorophore for moisture content evaluation in a hygroscopic polymer includes forming a blend that includes a hygroscopic polymer resin and a water-sensitive fluorophore. The process includes forming pellets having a particular geometry from the blend, determining fluorescence properties of at least one of the pellets, and determining moisture content of at least one of the pellets. The process also includes generating a calibration curve for the particular pellet geometry by correlating the fluorescence properties with the moisture content. The process further includes providing the calibration curve for non-destructive moisture content evaluation of a material derived from the pellets.