Lighting systems, methods, and devices for protecting human circadian neuroendocrine function during night use are described. Suitable lighting conditions can be provided for a working environment while protecting the circadian neuroendocrine systems of those occupying the illuminated workplace during the night. Lighting systems, methods, and devices can provide substantive attenuation of the pathologic circadian disruption in night workers. Lighting systems, methods, and devices can attenuate the specific bands of light implicated in circadian disruption. LED lighting systems, methods, and devices can provide increased intensity at a different portion of the spectrum than conventional LEDs, providing a useable white light even when unfavorable portions of the wavelength are attenuated by a notch filter. LED lighting systems, methods, and devices can switch between a daytime configuration and a night time configuration, wherein the daytime configuration provides unfiltered light and the night time configuration provides filtered light.

Alighting apparatus can include a light emitting element that can irradiate light, and an optical conversion layer disposed on the light emitting element for converting the irradiated light. The optical conversion layer can include crystal grains of a first phosphor and crystal grains of a second phosphor, and the crystal grains of the first phosphor and the crystal grains of the second phosphor can be in mixed form in the optical conversion layer.

Alighting apparatus can include a light emitting element that can irradiate light, and an optical conversion layer disposed on the light emitting element for converting the irradiated light. The optical conversion layer can include crystal grains of a first phosphor and crystal grains of a second phosphor, and the crystal grains of the first phosphor and the crystal grains of the second phosphor can be in mixed form in the optical conversion layer.

A curable organosilicon resin composition includes; (A) an organopolysiloxane having a resin structure containing 10 to 60 mol % of an R.sup.1SiO.sub.3/2 unit, 30 to 80 mol % of an (R.sup.2).sub.2SiO.sub.2/2 unit, and 1 to 30 mol % of an (R.sup.3).sub.3SiO.sub.1/2 unit. At least a part of the (R.sup.2).sub.2SiO.sub.2/2 unit is in continuous repeating units with the average number of the repeating units being 3 to 80. The organopolysiloxane has a weight average molecular weight of 5,000 to 50,000; the amount of the hydroxy groups bonded to silicon atoms is 0.001 to 1.0 mol/100 g; and the amount of the alkoxy groups, each having 1 to 10 carbon atoms, bonded to silicon atoms is 1.0 mol/100 g or less. A curable organosilicon resin composition has excellent workability, can give a cured product rapidly, and can make the cured product excellent in mechanical properties, heat resistance, crack resistance, and adhesive property, the surface tackiness being suppressed.

A curable organosilicon resin composition includes; (A) an organopolysiloxane having a resin structure containing 10 to 60 mol % of an R.sup.1SiO.sub.3/2 unit, 30 to 80 mol % of an (R.sup.2).sub.2SiO.sub.2/2 unit, and 1 to 30 mol % of an (R.sup.3).sub.3SiO.sub.1/2 unit. At least a part of the (R.sup.2).sub.2SiO.sub.2/2 unit is in continuous repeating units with the average number of the repeating units being 3 to 80. The organopolysiloxane has a weight average molecular weight of 5,000 to 50,000; the amount of the hydroxy groups bonded to silicon atoms is 0.001 to 1.0 mol/100 g; and the amount of the alkoxy groups, each having 1 to 10 carbon atoms, bonded to silicon atoms is 1.0 mol/100 g or less. A curable organosilicon resin composition has excellent workability, can give a cured product rapidly, and can make the cured product excellent in mechanical properties, heat resistance, crack resistance, and adhesive property, the surface tackiness being suppressed.

Lighting systems, methods, and devices for protecting human circadian neuroendocrine function during night use are described. Suitable lighting conditions can be provided for a working environment while protecting the circadian neuroendocrine systems of those occupying the illuminated workplace during the night. Lighting systems, methods, and devices can provide substantive attenuation of the pathologic circadian disruption in night workers. Lighting systems, methods, and devices can attenuate the specific bands of light implicated in circadian disruption. LED lighting systems, methods, and devices can provide increased intensity at a different portion of the spectrum than conventional LEDs, providing a useable white light even when unfavorable portions of the wavelength are attenuated by a notch filter. LED lighting systems, methods, and devices can switch between a daytime configuration and a night time configuration, wherein the daytime configuration provides unfiltered light and the night time configuration provides filtered light.

Proposed is a three-dimensional chiral metal nanoparticle, comprising a heterometal nanoparticle including: a seed region formed of a first metal; and a heterogeneous region disposed on an external side of the seed region to enclose the seed region and formed of a second metal. The first metal is gold (Au), and the second metal is palladium (Pd). In a rectangular parallelepiped structure, a rectangular band shape rotates in a clockwise direction or a counterclockwise direction on each surface and protrudes towards a center of the surface.

Proposed is a three-dimensional chiral metal nanoparticle, comprising a heterometal nanoparticle including: a seed region formed of a first metal; and a heterogeneous region disposed on an external side of the seed region to enclose the seed region and formed of a second metal. The first metal is gold (Au), and the second metal is palladium (Pd). In a rectangular parallelepiped structure, a rectangular band shape rotates in a clockwise direction or a counterclockwise direction on each surface and protrudes towards a center of the surface.

Photoluminescent sand preferably includes play sand, photoluminescent pigment, a powdered binder and a curing agent. The play sand is preferably mixed with the photoluminescent pigment to form a photo sand mix. The photo sand mix is then mixed with the powered binder and curing agent to form the photoluminescent sand mix. The photoluminescent sand mix is allowed to cure for between 3-7 days to form the photoluminescent sand.

Photoluminescent sand preferably includes play sand, photoluminescent pigment, a powdered binder and a curing agent. The play sand is preferably mixed with the photoluminescent pigment to form a photo sand mix. The photo sand mix is then mixed with the powered binder and curing agent to form the photoluminescent sand mix. The photoluminescent sand mix is allowed to cure for between 3-7 days to form the photoluminescent sand.