Article Abstract:
Researchers at Georgia Institute of Technology have developed an acoustic liner material that can withstand temperatures higher than 2,000 degrees F. The liner is made from tiny hollow spheres made at the institute for high-temperature insulation in the 1990s. It can absorb both low and high sound frequencies at levels comparable to traditional bulk-absorbing liners such as glass, fibers and foam. Noise data from an echo-free chamber indicate that the spheres can also control noise in a high- temperature flow environment.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
A method to produce tempered glass stronger and less variable was developed by Dr David J Green, a ceramics and materials professor at the Pennsylvania State University. Other researchers include VM Sglasvo of the University of Trento, Italy, and Dr R Tandon of Caterpillar Inc in Peoria, IL. A glass with an untempered surface, but with a tempered, compressed layer below was crated to have a stronger glass.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
This article discusses the fear of losing to posterity the nation's bird bald eagle and the recent encouraging developments for its restoration to a non-endangered species by the governmental and private agencies. Author mentions that introduction of dichlorodiphenyltrichloroethane made them nearly extinct.
User Contributions:
Comment about this article or add new information about this topic: