| 1 | They turned out to be the undiscovered elements scandium, gallium, technetium and germanium. | |
| 2 | The researchers used a gallium nitride semiconductor in the "proof of concept" tests. | |
| 3 | Molecules within the mixture will be automatically arranged in a string of thin, organic molecules in the periphery, gallium salt in the center. | |
| 4 | Each panel contains small lenses that concentrate sunlight by 400 times onto strips containing gallium arsenide photovoltaic cells. Dual-axis trackers follow the sun's trajectory. | |
| 5 | Using more efficient semiconductors, such as gallium arsenide, which is currently too expensive for anyone except NASA, is another. |