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HelloCthulhu
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- And after reading this paper, I thought testing the electrostatic repulsion of water on a hydrophilic surface would be an interesting experiment. I'd like to see if the water droplet starts dispersing into smaller droplets or not.
https://iopscience.iop.org/article/10.1088/0953-8984/17/28/R01
Even as a layman, I've been fascinated with the structure and activity of water for years. And after reading this paper, I thought testing the electrostatic repulsion of water on a hydrophilic surface would be an interesting experiment. I'd like to see if the water droplet starts dispersing into smaller droplets or not. Here's a snippet of the affect I'd like to get close to recreating:
https://iopscience.iop.org/article/10.1088/0953-8984/17/28/R01
pg. 21, Fig 13
"In the same publication, Vallet et al [31] also reported another phenomenon that occurred only for low conductivity liquids (deionized water and water–ethanol mixtures). For these liquids, the contact line was found to become unstable at high voltage leading to the ejection of small satellite droplets from the edge of the main droplet with a characteristic lateral spacing. This observation was later reproduced by Mugele and Herminghaus [54] for mixtures of water and glycerol (see figure 13). Qualitatively, this instability is due to the mutual repulsion of like charges at the contact line. Beyond a certain threshold voltage, surface tension can no longer balance the electrostatic repulsion and the emission of satellites sets in."
I have distilled water. A digital pipette that can dispense samples as small as 0.1 μL. Adhesive microscope slides. Copper plates I can shape and use as electrodes. A high voltage AC/DC power supply (≤15kV) and it's worked really well for 100 mL water bridge experiments so far. Only thing I don't have yet are lab grade glycerol or silicone oil.
Here's a diy electrowetting setup from Gaudi Labs:
I think they're using silicone oil and oil ink in this demo.
I'd like to just try a sample of 10 mL distilled water on a hydrophilic glass slide with two 10 mm x 10 mm copper electrodes underneath to start and see if any deformities occur during high AC or DC voltage. Any advice is greatly appreciated!
https://iopscience.iop.org/article/10.1088/0953-8984/17/28/R01
pg. 21, Fig 13
"In the same publication, Vallet et al [31] also reported another phenomenon that occurred only for low conductivity liquids (deionized water and water–ethanol mixtures). For these liquids, the contact line was found to become unstable at high voltage leading to the ejection of small satellite droplets from the edge of the main droplet with a characteristic lateral spacing. This observation was later reproduced by Mugele and Herminghaus [54] for mixtures of water and glycerol (see figure 13). Qualitatively, this instability is due to the mutual repulsion of like charges at the contact line. Beyond a certain threshold voltage, surface tension can no longer balance the electrostatic repulsion and the emission of satellites sets in."
I have distilled water. A digital pipette that can dispense samples as small as 0.1 μL. Adhesive microscope slides. Copper plates I can shape and use as electrodes. A high voltage AC/DC power supply (≤15kV) and it's worked really well for 100 mL water bridge experiments so far. Only thing I don't have yet are lab grade glycerol or silicone oil.
Here's a diy electrowetting setup from Gaudi Labs:
I think they're using silicone oil and oil ink in this demo.
I'd like to just try a sample of 10 mL distilled water on a hydrophilic glass slide with two 10 mm x 10 mm copper electrodes underneath to start and see if any deformities occur during high AC or DC voltage. Any advice is greatly appreciated!