Quantum dots that are cadmium-free and/or stoichiometrically tuned are disclosed, as are methods of making them. Inclusion of the quantum dots and others in a stabilizing polymer matrix is also disclosed. The polymers are chosen for their strong binding affinity to the outer layers of the quantum dots such that the bond dissociation energy between the polymer material and the quantum dot is greater than the energy required to reach the melt temperature of the cross-linked polymer.

This fluorescence observation method is a method of observing a living organism into which a fluorescent dye is injected. The method includes the steps of: irradiating the living organism with excitation light including a wavelength for exciting the fluorescent dye using a light irradiation means, acquiring a first fluorescence image of the living organism generated by the irradiation with the excitation light using an image acquisition means, specifying an observation object in the living organism on the basis of the first fluorescence image; acquiring a second fluorescence image of the observation object generated by the irradiation with the excitation light using the image acquisition means; and specifying a linear fluorescence pattern appearing in the second fluorescence image.

This fluorescence observation method is a method of observing a living organism into which a fluorescent dye is injected. The method includes the steps of: irradiating the living organism with excitation light including a wavelength for exciting the fluorescent dye using a light irradiation means, acquiring a first fluorescence image of the living organism generated by the irradiation with the excitation light using an image acquisition means, specifying an observation object in the living organism on the basis of the first fluorescence image; acquiring a second fluorescence image of the observation object generated by the irradiation with the excitation light using the image acquisition means; and specifying a linear fluorescence pattern appearing in the second fluorescence image.

According to one embodiment, a scintillator includes a host material having the chemical formula: A.sub.2BX.sub.6, where A includes a monovalent ion, B includes a tetravalent ion, and X includes a halide ion.

According to one embodiment, a scintillator includes a host material having the chemical formula: A.sub.2BX.sub.6, where A includes a monovalent ion, B includes a tetravalent ion, and X includes a halide ion.

Compositions relating to three-dimensional (3D) printing. In particular, a photochromatic composition for use in 3D printing comprising a photochrome core with polymeric resin shell disposed thereon and a polymeric component.

A crystal material that is represented by a general formula (1): (RE.sub.xA.sub.1-x-y-sB.sub.yM.sub.s).sub.2+?(Si.sub.1-t,M.sub.t).sub.2+?O.sub.7+? (1), the crystal material having a pyrochlore type structure, being a nonstoichiometric composition, and being a congruent melting composition, wherein in Formula (1), A contains at least one or more selected from Gd, Y, La, Sc, Yb, and Lu; B contains at least one or more selected from La, Gd, Yb, Lu, Y, and Sc; 0.1?y<0.4; RE contains at least one or more selected from Ce, Pr, Nd, Eu, Tb, and Yb; 0<x<0.1; M and M contain at least one or more selected from Li, Na, K, Mg, Ca, Sr, Ba, Ti, Zr, Hf, Fe, Ta, and W; 0?s<0.01 and 0?t<0.01; and 0<|?|<0.3 and 0?|?|<0.3 and 0?|?|<0.5.

A wavelength-converting polymer, a method for fabricating the same and a wavelength-converting device employing the same are provided. The wavelength-converting polymer has a chemical structure represented by formula (I): ##STR00001## In formula (I), B and D are the same or different and independently include hydrogen, C1-8 alkyl group, C1-8 alkoxy group, aryloxy group, carboxyl group, COOK, COONa or NH.sub.2, or B and D are connected to form a heteroaromatic ring, ##STR00002##
wherein Z is hydrogen, C1-8 alkyl group, cycloalkyl group or aryloxy group, X.sub.1-X.sub.4 are the same or different and independently include hydrogen, halogen, C1-8 alkyl group or C1-8 alkoxy group, R is C1-8 alkyl group with or without substitution, and n is an integer of 5 to 1,000.

An object of the invention is to provide a high-performance organic electroluminescence device and an electronic device including the organic electroluminescence device. An organic electroluminescence device includes an anode, a cathode and an emitting layer, in which the emitting layer includes a first compound and a second compound, the first compound is a delayed fluorescent compound, and the second compound is represented by a formula (2) below. ##STR00001##

According to one embodiment, an illumination device includes a light emitting chip including a main surface and a side surface and emitting light, a sealing member including a scattering member and sealing the main surface and the side surface, and a wavelength converting member converting a wavelength of the light emitted from the light emitting chip.