The nanoparticle size distribution can be determined using numerous commercially available instruments. However, such techniques make very convenient but too simplistic assumption that every particle is a sphere. The following tutorial shows how to describe particles size using multiple length and width measures based on SEM (Scanning Electron Microscope) image. 

http://youtu.be/D5KL40CFXqA

This method provides greater accuracy and allows us to determine surface-to-volume ratio which together with size effects of nanoparticles introduces many size/shape-dependent phenomena such as chemical, electrochemical, electronic, magnetic and mechanical properties. This approach is based on manual measurement of each particle which may be very time consuming. However, it may be the only solution to get accurate particle size distribution and aspect ratio when automated image analysis methods fail (i.e. most cases). 

Subscribe to KEEP CALM and PUBLISH PAPERS YouTUBE channel that includes a number of graphical video tutorials to scientific publishing. 

https://www.youtube.com/channel/UCqKuaNlHwxUVDSRt8iLPeNw

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