Agglomeration of Nanoparticles in a Stirred Vessel

The samples taken were stored in a freezer at temperatures below —30°C (3) They were freeze dried by freezing them to temperatures below —70°C by immersing them in an isopropanol-dry ice bath and subjecting them to vacuum. The temperature was gradually brought up to room temperature over a period of 48-72 h. 

The sample tube was removed without opening and placed inside a dessicator within a freezer to maintain it in a water-free environment. 

A small amount of sample was carefully mounted on an SFM sample mount using a thin layer of conductive carbon paste just prior to the procedure. 

The sample was coated with a thin layer of gold to make it conductive. 

The samples mounted were observed in the SEM (JEOL-72C) and micrographs of representative particle populations were obtained. 

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