noun, Biology. 1. an orientation of an organism to an external stimulus, as light, especially by growth rather than by movement. Origin of tropism. 1895-1900. First recorded in 1895-1900; independent use of -tropism. Related forms. tropismatic.
Friction on as-grown graphene (Fig. 1c) is ultra-low and rather uniform with its magnitude close to the previous reports4. In contrast, friction on graphene after ï¬uorination becomes
1 This illustration shows the simulation results of tensile and compression tests on 3-D graphene. 2  3-D-printed gyroid models such as this one were used to test the strength and mechanical properties of a new lightweight material. 3  This illustration shows the simulation results of tensile and compression tests on 3-D graphene.