Xiong, Ziye
(2013)
Pattern Formation in Drying Drops of Colloidal Solutions.
Master's Thesis, University of Pittsburgh.
(Unpublished)
This is the latest version of this item.
Abstract
The deposited residue from evaporated drops of colloidal solutions can exhibit a wide variety of interesting and reproducible patterns. A familiar example is the ring-like residue associated with the "coffee ring effect"[1]. This phenomenon was first explained by Deegan, et al as due to outward (radial) flows introduced by evaporation driving the suspended particles to the self-pinned edge, creating a "coffee ring" structure at the drop perimeter. This behavior has drawn the attention of a number of other researchers interested in its applications and relevance to industrial processes and technology (i.e. printing, coating, and medical diagnostics). Recently, certain diseases have been associated with specific patterns in dried drops of blood serum [2]. Important studies on the key mechanisms of the process (e.g. evaporation kinetics, internal flow motions, triple line dynamics role in evaporative self-assembly phenomena) have also appeared. During the evaporation of colloidal sessile droplets, capillary and Marangoni flow and Van der Waals forces work together. With so many factors effecting pattern formation, small changes in solution composition can lead to significant changes in the resulting patterns. In this research project, model solutions are made using a base lysozyme protein aqueous solution mixed with aqueous sodium chloride solutions of various concentrations. Droplet patterns from these colloidal solutions are examined by atomic force microscope and digital optical microscope. The sodium chloride concentration dependent patterns are analyzed and the temporal stability of these patterns in air at room temperature is monitored over several months.
Share
Citation/Export: |
|
Social Networking: |
|
Details
Item Type: |
University of Pittsburgh ETD
|
Status: |
Unpublished |
Creators/Authors: |
|
ETD Committee: |
|
Date: |
27 June 2013 |
Date Type: |
Publication |
Defense Date: |
21 March 2013 |
Approval Date: |
27 June 2013 |
Submission Date: |
25 March 2013 |
Access Restriction: |
No restriction; Release the ETD for access worldwide immediately. |
Number of Pages: |
79 |
Institution: |
University of Pittsburgh |
Schools and Programs: |
Swanson School of Engineering > Materials Science and Engineering |
Degree: |
MS - Master of Science |
Thesis Type: |
Master's Thesis |
Refereed: |
Yes |
Uncontrolled Keywords: |
Pattern formation,colloidal solutions,lysozyme,microdroplet. |
Date Deposited: |
27 Jun 2013 15:01 |
Last Modified: |
15 Nov 2016 14:11 |
URI: |
http://d-scholarship.pitt.edu/id/eprint/18077 |
Available Versions of this Item
-
Pattern Formation in Drying Drops of Colloidal Solutions. (deposited 27 Jun 2013 15:01)
[Currently Displayed]
Metrics
Monthly Views for the past 3 years
Plum Analytics
Actions (login required)
|
View Item |