Drying of poly(ethylene oxide) droplet viewed from beneath

submitted by: David Fairhurst
Drying of a 75μL droplet of 20% poly(ethylene oxide) solution in water, viewed from beneath using an inverted microscope (Nikon Eclipse TE2000-S) with 2x objective lens. The image measure 5mm across and the frame rate is increased by a factor of 300. The bright specks in the droplet are small clusters of polymer that would not dissolve, and help to visualise the flow within the droplet. Pinned drying (stage 1) occurs for the first 5 seconds, during which there is clear evidence for...

Drying of 40% poly(ethylene oxide) droplet

submitted by: David Fairhurst
Drying of a 75μL droplet of 40% poly(ethylene oxide) solution in water. The duration of the experiment was approximately 2 hours, the distance across the image approximately 10mm. Timings given below are given relative to the video, to aid identification of the various stages and processes. The droplet shows a very short stage 1, around 1 second. The contact angle increases until 3 seconds and bootstrap deposition (stage 3) continues until 4 seconds. However, there is still liquid inside...

Drying of 25% poly(ethylene oxide) droplet

submitted by: David Fairhurst
Drying of a 75μL droplet of 25% poly(ethylene oxide) solution in water. The duration of the experiment was approximately 2 hours, the distance across the image approximately 10mm. Timings given below are given relative to the video, to aid identification of the various stages and processes. The droplet exhibits stage 1 pinned drying for the first 5 seconds. However, the solid deposit is already much thicker for this droplet, than those with lower concentration. As the contact angle is...

Drying of 8% poly(ethylene oxide) droplet

submitted by: David Fairhurst
Drying of a 75μL droplet of 8% poly(ethylene oxide) solution in water. The duration of the experiment was approximately 2 hours, the distance across the image approximately 10mm. Timings given below are given relative to the video, to aid identification of the various stages and processes. The droplet exhibits pinned drying (stage 1) for around the first 5 seconds, at which point the contact line depins and the droplet undergoes a dewetting transition (stage 2) until 9 seconds. At this...

Drying of 5% poly(ethylene oxide) droplet

submitted by: David Fairhurst
Drying of a 75μL droplet of 5% poly(ethylene oxide) solution in water. The duration of the experiment was approximately 2 hours, the distance across the image approximately 10mm. Timings given below are given relative to the video, to aid identification of the various stages and processes. The droplet exhibits pinned drying (stage 1) for around the first 5 seconds, before depinning when the contact angle becomes lower than the measured receding contact angle. Stage 2 and bootstrap...

SDSU Geological Sciences Webinar - Stephen T. Hasiotis

submitted by: tcarrasc
Ichnology for the 21st Century: Understanding the differences between continental and marine trace fossils, with implications to the diversity, distribution, and evolution of soil biota ; Department of Geological Sciences, San Diego State University, Seminar Series ; The study of ichnology has come a long way since its inception and it continues to evolve. In particular, progress is being made in understanding the implications of trace fossils in the continental realm and how they can be...

How Much Water Do We Use?

submitted by: CUAHSI-dk

Developed as part of the CUAHSI Watershed Media Project.

Safe Hydrogel Padding: use in safe clothing

submitted by: GZE

Polymer effect (Hydrogel particles inside PU melt matrix):
The polymer coating will absorb and bind the excess of moisture migrating through the FR cotton fabric if the temperature is maintained below the threshold.
In case temperature increases, the coating will release the sweat accumulated, reproducing the human natural sweating process through evaporative cooling.
Projected and developed by Grado Zero Espace -www.gzespace.com