Difference between revisions of "Assignment 5, Part 1: viscosity and diffusivity in glycerolwater mixtures"
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:* From the viscosity calculation, estimate the glycerin/water weight ratio. (This [https://dl.dropboxusercontent.com/u/12957607/Viscosity%20of%20Aqueous%20Glycerine%20Solutions.pdf chart] is a useful reference. If that link doesn't work try [http://profs.engineering.uottawa.ca/biofluid/files/2011/08/viscosityofaqueousglycerinesolutions.pdf this one].)  :* From the viscosity calculation, estimate the glycerin/water weight ratio. (This [https://dl.dropboxusercontent.com/u/12957607/Viscosity%20of%20Aqueous%20Glycerine%20Solutions.pdf chart] is a useful reference. If that link doesn't work try [http://profs.engineering.uottawa.ca/biofluid/files/2011/08/viscosityofaqueousglycerinesolutions.pdf this one].)  
−  {{Template:Assignment Turn Inmessage=for the viscosity part:  +  {{Template:Assignment Turn Inmessage=Turn in for the viscosity part: 
# Procedure  # Procedure  
#* Document the samples you prepared and used and how you captured images (camera settings including frame acquisition rate, number of frames, number of particles in the region of interest, choice of sample plane, etc)  #* Document the samples you prepared and used and how you captured images (camera settings including frame acquisition rate, number of frames, number of particles in the region of interest, choice of sample plane, etc) 
Revision as of 18:39, 6 September 2017
This is Part 1 of Assignment 5.
Estimating the diffusion coefficient by tracking suspended microspheres
1. Track some 0.84μm Nile Red Spherotech polystyrene beads in waterglycerin mixtures (Samples A and B contain 30% and 50% glycerin, respectively).
 Notes: Fluorescent microspheres have been mixed for you by the instructors into waterglycerin solutions A and B. (a) Vortex the stock Falcon tube, and then (b) transfer the bead suspension into its imaging chamber (consisting of a microscope slide, doublesided tape delimiting a 2mm channel, and a 22mm x 40mm No. 1.5 coverslip, and sealed at both ends nail polish).
 Tip 1: Do not choose to monitor particles that remain stably in focus: these are likely to be 'sitting on the coverslip' and their motion will not be representative of diffusion in the viscous waterglycerol fluid.
 Tip 2: Limit the ROI to a region with only 3 or 4 particles. Long movies with the whole field of view is a sure way to make MATLAB complain.
2. Estimate the diffusion coefficient of these samples: MSD = $ \left \langle {\left  \vec r(t+\tau)\vec r(t) \right \vert}^2 \right \rangle=2Dd\tau $, where r(t) = position, d = number of dimensions, D = diffusion coefficient, and $ \tau $= time interval.
Turn in for the viscosity part:

Back to Assignment 5.