Provided is an oxysulfide luminescent material. The luminescent material has a general chemical formula of Ln.sub.2xO.sub.2S:Eu.sub.x.sup.3+@M.sub.y, wherein@ is coating, Eu is doped in Ln.sub.2xO.sub.2S, Ln.sub.2xO.sub.2S:Eu.sup.x.sub.3+has a porous structure, and M is located in pores of the Ln.sub.2xO.sub.2S:Eu.sub.x.sup.3+. In the oxysulfide luminescent material, metal nano particles coating is used to form a core-shell structure, which increases luminescent efficiency of the oxysulfide luminescent material in a same excitation condition; in addition, a hollow structure is formed between a core and a shell layer of the oxysulfide luminescent material, which effectively reduces usage of rare earth elements in the shell layer and lowers cost of the luminescent material. Also provided is a preparation method for the oxysulfide luminescent material.

The invention belongs to the field of luminescent materials. Disclosed are silicate luminescent materials doped with metal nano particles and preparation methods there for. The silicate luminescent materials doped with metal nano particles are represented by the chemical formula:MLn.sub.1-xSiO.sub.4:xRE,yA; wherein M is one or two elements selected from Li, Na and K; Ln is one or two elements selected from Y, Sc, La and Lu; A is a metal nano particle selected from Ag, Au, Pt, Pd and Cu; RE is one or two ions selected from Eu, Gd, Tb, Tm, Sm, Ce and Dy; 0<x0.1; 0<y0.005. When silicate luminescent materials doped with metal nano particles of the invention are excitated by electron beam, they have higher luminescent efficiency. The luminescent materials are good to be used in field emission light source devices.

Provided is a carbon nanostructure including a plurality of organic molecules that are decomposition products of an organic solvent. The carbon nanostructure includes a carbon nanostructure core and a plurality of organic molecules bound to and grown on the carbon nanostructure core, wherein the carbon nanostructure core is a combination of the organic molecules.

Provided is a carbon nanostructure including a plurality of organic molecules that are decomposition products of an organic solvent. The carbon nanostructure includes a carbon nanostructure core and a plurality of organic molecules bound to and grown on the carbon nanostructure core, wherein the carbon nanostructure core is a combination of the organic molecules.

Provided are compounds comprising a ligand L.sub.A of Formula I ##STR00001##
where the ligand L.sub.A is coordinated to Ir.

Provided are compounds comprising a ligand L.sub.A of Formula I ##STR00001##
where the ligand L.sub.A is coordinated to Ir.

Provided are compounds comprising a ligand L.sub.A of Formula I

##STR00001##

where the ligand L.sub.A is coordinated to Pt.

Provided are compounds comprising a ligand L.sub.A of Formula I

##STR00001##

where the ligand L.sub.A is coordinated to Pt.

Novel clay stabilization compounds comprising metal-doped carbon quantum dots, methods of their manufacture, oilfield drilling fluid compositions containing the clay stabilization compounds and methods of their use are disclosed. The novel clay stabilization compounds are useful, inter alia, to reduce clay swelling in use, have higher penetration rates than oil-based fluids, are more environmentally acceptable, employable at much lower concentrations, are reusable, may be used in a wider range of drilling fluids including, for example, seawater-based drilling fluids and/or more cost-effective in use.

Novel clay stabilization compounds comprising metal-doped carbon quantum dots, methods of their manufacture, oilfield drilling fluid compositions containing the clay stabilization compounds and methods of their use are disclosed. The novel clay stabilization compounds are useful, inter alia, to reduce clay swelling in use, have higher penetration rates than oil-based fluids, are more environmentally acceptable, employable at much lower concentrations, are reusable, may be used in a wider range of drilling fluids including, for example, seawater-based drilling fluids and/or more cost-effective in use.