A thermal analysis of cluster-cluster coalescence was performed using a macroscopic model describing: (1) Energy released due to surface area reduction. (2) Energy accumulation in the coalescing particles that can lead to melting. (3) Energy dissipation to the surrounding medium that can lead to evaporation of the heptane and formation of a thin insulating layer of vapor surrounding each particle (in analogy to the Leidenfrost effect in boiling). The simulations reveal the possibility of melting and recrystallization of nanoparticles, thus explaining the formation of single crystals in a medium that is at room temperature.
A microfluidic system for quantum dot synthesis in microemulsions has been designed by coupling a model that describes the two phases of the microemulsion as interpenetrating continua with the mesoscopic model of quantum dot formation in a single nanodroplet. The models were coupled through the interfacial flux of hydrogen selenide. The effects of operating conditions, such as inlet flow rate and supply of hydrogen selenide to the microemulsion, on the growth rate of clusters and nanocrystals have been studied using this multi-scale modeling approach.
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