Abstract: A light-emitting element includes an anode electrode, a QD layer containing QDs, and a cathode electrode, in which the QDs are Cd-free quantum dots having a core-shell structure including a core containing at least Ag, Ga, and at least one of S and Se, and a shell containing at least Zn, and exhibit fluorescence characteristics with a fluorescence full-width at half-maximum of 40 nm or less and a fluorescence quantum yield percentage of 70% or more.

Abstract: A light-emitting element includes an anode electrode, a cathode electrode, and a QD layer provided between the anode electrode and the cathode electrode, the QD layer containing the QDs. The QDs are AgInxGa1-xSySe1-y-based or ZnAgInxGa1-xSySe1-y-based Cd-free QDs (0?x<1, 0?y?1) and exhibit fluorescence characteristics having a fluorescent half width of 45 nm or less and a fluorescence quantum yield of 35% or more in a green wavelength region to a red wavelength region.

Abstract: It is intended to provide a method whereby a protein can be separated and purified at a high accuracy by a convenient procedure. A sample containing the desired protein is brought into contact with an ion exchanger under first conditions at a high ionic strength and at pH value not in the vicinity of the isoelectric point of the desired protein. Next, the component adsorbed by the ion exchanger is eluted under second conditions at a lower ionic strength than in the first conditions and at a pH value closer to the isoelectric point of the desired protein than in the first conditions.