In a surface modification method for fluoride luminescent materials, an inorganic coating layer A.sub.xMF.sub.y coated substrate A.sub.xMF.sub.y:Mn.sup.4+ is mixed with an organic solution containing a metal phosphate, an alkoxysilane, an organic carboxylic acid or an organic amine. The solution is evaporated to give the organic-inorganic coating layer coated surface-modified fluoride luminescent material. The phosphor photoluminescence intensity and quantum efficiency of the modified phosphors can be maintained at 85%-95% under high temperature and high humidity conditions. After being coated with the inorganic coating layer, the surface defects of the phosphor are reduced, and the photoluminescence intensity and quantum yield of the phosphor are increased by 5%-15%. After being coated with the organic coating layer, the photoluminescence intensity of the phosphor is reduced <3%.

The present invention provides a quantum dot of which a surface is passivated with a short chain ligand, and a method of passivating a surface of the quantum dot using a ligand exchange reaction.

An organometallic compound represented by Formula 1: ##STR00001## wherein in Formula 1, groups and variables are the same as described in the specification.

An organometallic compound represented by Formula 1: ##STR00001## wherein in Formula 1, groups and variables are the same as described in the specification.

A conjugated polymer comprises repeating units as represented by formula (I),
A-B.sub.p  (I) p is the number of the repeating units, and p is an integer more than or equal to 1; and A has a structure as represented by formula (II), and B has a structure as represented by formula (II) or formula (III). ##STR00001## The described conjugated polymer has a higher triplet energy level and a higher charge transfer property.

The present invention provides an anti-counterfeit marking technique for verifying authenticity of objects using x-rays fluorescence (XRF) analysis.

The present invention provides an anti-counterfeit marking technique for verifying authenticity of objects using x-rays fluorescence (XRF) analysis.

A method of applying a trivalent chromium or chromium-free conversion coating to a metallic substrate including mixing a dye compound that interacts with electromagnetic radiation outside the human visual spectrum but not electromagnetic radiation that is within the human visual spectrum to produce an observable emission into the trivalent chromium or chromium-free conversion coating mixture to allow for inspection of the coating after applied with a correlating electromagnetic radiation source.

A wavelength conversion element includes: a plate; and a wavelength conversion layer disposed on the plate and including: an inorganic matrix; an inorganic wavelength conversion material dispersed in the inorganic matrix and configured to emit light having a different wavelength than does incident light; and a polymer material in the inorganic matrix, wherein both the inorganic matrix and the polymer material are in contact with the plate.

A phosphor plate including a base material, and a plate-shaped composite including phosphors dispersed in the base material, in which a main component of the base material is alumina, the phosphor includes an α-type sialon phosphor, and L* value satisfies 73.5 or more and 85.0 or less, a* value satisfies 4.4 or more and 8.0 or less, and b* value satisfies 10.8 or more and 13.0 or less in L*a*b* color coordinates of the phosphor plate in a case of being measured in accordance with JIS Z 8781-4.