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
Graphite is a soft, crystalline polymorph of carbon, and while it shares the same chemistry as diamond the two have very different physical properties (see diamond for examples).Graphite exhibits both metallic and non-metallic properties.raphite is a soft, crystalline polymorph of carbon, and while it shares the same chemistry as diamond the two have very different physical properties (see diamond for examples).