Abstract: A system for isolating sound generated by an aircraft utilizing a helipad may include a plurality of acoustic scatterers being disposed adjacent to at least a portion of a perimeter of the helipad. Each of the plurality of acoustic scatterers include channels having an open end and a terminal end. Additionally, each of the plurality of acoustic scatterers has an acoustic monopole response and an acoustic dipole response with a resonant frequency that is substantially similar to one another.

Abstract: Systems and devices are disclosed herein for absorbing unwanted target sounds. In one example, an acoustic scatterer for absorbing a target sound includes a housing defining a plurality of channels having an open end and a terminal end. The terminal ends of the plurality of channels are separate from each other and extend along a length of the housing. The acoustic scatterer also includes one or more spacers subdividing the plurality of channels along the length of the housing. In another example, a system for absorbing a target sound includes a plurality of acoustic scatterers, each having a housing that defines a plurality of channels having an open end and a terminal end. The terminal ends of the plurality of channels are separate from each other and extend along a length of the housing. The plurality of acoustic scatterers are stacked on top of each other in a lengthwise direction.

Abstract: The present invention provides a dental glass composition that has excellent fixability to dental prostheses, and that does not need firing and fixing to layer color or enable a build-up of porcelain thereon. The present invention relates to a dental glass composition comprising a glass powder (A) and a wax component (B). The glass powder (A) has an average particle diameter of preferably 0.05 ?m to 50 ?m. The wax component (B) has a boiling point of preferably 400° C. or less.

Abstract: Provided is a zirconia sintered body that suppresses discoloration due to porcelain. The zirconia sintered body comprises at least one of a coloring agent A: erbium oxide and a coloring agent B: nickel oxide, and a composite oxide of zirconium and vanadium.

Abstract: A zirconia sintered body that suppresses discoloration due to porcelain. The zirconia sintered body contains at least one of a coloring agent A, which is erbium oxide and a coloring agent B, which is nickel oxide, and contains a composite oxide of zirconium and vanadium. A composition, containing zirconium oxide, yttrium oxide, and a coloring agent, where the coloring agent contains at least one of a coloring agent A, which is erbium oxide and a coloring agent B, which is nickel oxide, and contains a coloring agent C, which is a composite oxide of zirconium and vanadium.

Abstract: A zirconia sintered body that suppresses discoloration due to porcelain. The zirconia sintered body contains at least one of a coloring agent A, which is erbium oxide and a coloring agent B, which is nickel oxide, and contains a composite oxide of zirconium and vanadium. A composition, containing zirconium oxide, yttrium oxide, and a coloring agent, where the coloring agent contains at least one of a coloring agent A, which is erbium oxide and a coloring agent B, which is nickel oxide, and contains a coloring agent C, which is a composite oxide of zirconium and vanadium.

Abstract: Provided is a zirconia sintered body that suppresses discoloration due to porcelain. The zirconia sintered body comprises at least one of a coloring agent A: erbium oxide and a coloring agent B: nickel oxide, and a composite oxide of zirconium and vanadium.