Solar cells that provide as much as 50% more power for Earth-orbiting satellites will help flash back telephone and television signals from space. The cells are based on the two-junction, gallium indium phosphide on gallium arsenide designs developed at the Department of Energy's National Renewable Energy Laboratory (NREL) (Golden, CO). TECSTAR Inc. (City of Industry, CA) licensed two patents covering the technology for space use. It has adapted the NREL technology to use germanium substrates for the epitaxial growth of the cells. This, in turn, should result in greater efficiencies and reduced costs for space missions. Commonly used silicon cells lose about half of their efficiency after five years in space. The gallium indium phosphide top layers of the new NREL cells have far more resistance to radiation damage, giving them a much longer space life. E-mail email@example.com.
The choice between helical and spur gears in gearboxes may seem straightforward. But with planetary gearboxes, however, the choice between helical and spur gears requires some additional thought. Here’s what you need to know to make the right choice.
Cas Smith is a biological engineer at Terrapin Bright Green, a consulting firm that specializes in green and sustainable design. At the core of his work is to explore how biomimicry can inform sustainable design. He discussed biomimicry and its implications for design and solving some of the world’s sustainability issues in an interview with Design News.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.