A new class of pH sensitive fluorescent dyes and assays relating thereto are described. The dyes and assays are particularly suited for biological applications including phagocytosis and monitoring intracellular processes. The pH sensitive fluorescent dyes of the present invention include compounds of Formula I: ##STR00001## wherein the variables are described throughout the application.

Provided is a thermosensitive recording medium having excellent oil resistance among various performances required for the thermosensitive recording medium. The thermosensitive recording medium has a thermosensitive recording layer comprising a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate, wherein the thermosensitive recording layer contains N-[2-(3-phenylureido)phenyl] benzenesulfonamide and an urea-based compound represented by the general formula 1 as the electron accepting color developing agents, ##STR00001##
wherein R.sup.1 represents a substituted or unsubstituted alkyl group, aralkyl group or aryl group, and R.sup.2 represents a hydrogen atom or an alkyl group.

Provided is a thermosensitive recording medium having excellent oil resistance among various performances required for the thermosensitive recording medium. The thermosensitive recording medium has a thermosensitive recording layer comprising a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate, wherein the thermosensitive recording layer contains N-[2-(3-phenylureido)phenyl] benzenesulfonamide and an urea-based compound represented by the general formula 1 as the electron accepting color developing agents, ##STR00001##
wherein R.sup.1 represents a substituted or unsubstituted alkyl group, aralkyl group or aryl group, and R.sup.2 represents a hydrogen atom or an alkyl group.

Systems and methods are described whereby a deoxygenated liquid dye material is made by supplying the deoxygenated inert gas to a liquid dye material that is susceptible to oxidation, and mixing the liquid dye material in the presence of the supplied deoxygenated inert gas with water and at least one dye formulation component selected from the group consisting of reducing agents, pH adjusters, foaming agents, wetting agents and auxiliary chemicals to form a deoxygenated aqueous dye composition having an oxygen content of 30 ppm oxygen or less. A supply of inert gas may be provided which is then passed to a gas purifier to reduce oxygen content in the inert gas to, e.g., 1 ppb oxygen or less. The deoxygenated aqueous dye composition that is formed may have an oxygen content of 1 ppm or less.

Systems and methods are described whereby a deoxygenated liquid dye material is made by supplying the deoxygenated inert gas to a liquid dye material that is susceptible to oxidation, and mixing the liquid dye material in the presence of the supplied deoxygenated inert gas with water and at least one dye formulation component selected from the group consisting of reducing agents, pH adjusters, foaming agents, wetting agents and auxiliary chemicals to form a deoxygenated aqueous dye composition having an oxygen content of 30 ppm oxygen or less. A supply of inert gas may be provided which is then passed to a gas purifier to reduce oxygen content in the inert gas to, e.g., 1 ppb oxygen or less. The deoxygenated aqueous dye composition that is formed may have an oxygen content of 1 ppm or less.

A new class of pH sensitive fluorescent dyes and assays relating thereto are described. The dyes and assays are particularly suited for biological applications including phagocytosis and monitoring intracellular processes. The pH sensitive fluorescent dyes of the present invention include compounds of Formula I:

##STR00001## wherein the variables are described throughout the application.

A new class of pH sensitive fluorescent dyes and assays relating thereto are described. The dyes and assays are particularly suited for biological applications including phagocytosis and monitoring intracellular processes. The pH sensitive fluorescent dyes of the present invention include compounds of Formula I:

##STR00001## wherein the variables are described throughout the application.

An aqueous dispersion of an embodiment includes visible-light responsive photocatalytic composite microparticles containing tungsten oxide and zirconium oxide, and an aqueous dispersion medium in which the photocatalytic composite microparticles are dispersed. In the photocatalytic composite microparticles, a ratio of a mass of the zirconium oxide to a mass of the tungsten oxide is in a range of from 0.05% to 200%, and a D50 particle size in particle size distribution is in a range of from 20 nm to 10 ?m. The aqueous dispersion has pH in a range of from 1 to 9.

A new class of pH sensitive fluorescent dyes and assays relating thereto are described. The dyes and assays are particularly suited for biological applications including phagocytosis and monitoring intracellular processes. The pH sensitive fluorescent dyes of the present invention include compounds of Formula I: ##STR00001## wherein the variables are described throughout the application.

A new class of pH sensitive fluorescent dyes and assays relating thereto are described. The dyes and assays are particularly suited for biological applications including phagocytosis and monitoring intracellular processes. The pH sensitive fluorescent dyes of the present invention include compounds of Formula I: ##STR00001## wherein the variables are described throughout the application.