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
The reaction C(s)diamondâC(s)graphite has a negative change in Gibbs free energy and is therefore thermodynamically favorable at 25Â°C and 1 atm. However, even though favorable, it is so slow that it is not observed. Whether a reaction is thermodynamically favorable does not determine its rate.