Chemistry

Jaw-dropping “unmixing” demo appears to reverse entropy

I identify as a scientist, but I gotta admit: When I saw this video from Steve Spangler Science, my first impulse was to jump back from the computer, cross myself, and douse the screen with holy water. It reminded me of a line from John Carpenter’s underappreciated 1987 horror movie, Prince of Darkness:

And we assume time is an arrow because it is as a clock…Cause precedes effect – fruit rots, water flows downstream. We’re born, we age, we die. The reverse NEVER happens…

Unless, apparently, you’re dealing with a system operating under conditions of laminar flow. Obviously, there is no real “violation” of the second law of thermodynamics, here, but because almost all of our intuitions about how liquids are going to behave are formed under conditions of turbulent flow, it sure does seem like it.

Continue Reading Sean Michael Ragan14
Make: Projects – PVC utility sink stand

Make: Projects – PVC utility sink stand

All the kitchen chemistry at my last place left the sink in no condition for human habitation, so I replaced it when I moved out, and took the old one with me. After some diligent scrubbing, it was ready to serve as a utility sink in my garage/workshop, hooked up to the washer/dryer connection there. All I lacked was a stand, and since I’d recently scored a bunch of these cool orange-colored Blazemaster PVC fittings at the Habitat for Humanity ReStore for a song, I decided to make one out of PVC.

Continue Reading Sean Michael Ragan

Jeri homebrews her own EL ink!

Our geek BFF, Jeri Ellsworth, has tickled our exploratory fancies again (and continued to push the “don’t try this at home” envelope) with a chemistry hack of re-doping common ZnS:Cu green glow powder to arrive at her own blue electroluminescent (EL) powder. Nice work, Jer! Make Electroluminescent (EL) Ink at Home – Re-doping Glow Powder

Continue Reading Gareth Branwyn2
Homemade high resolution DLP 3D printer

Homemade high resolution DLP 3D printer

This link came in the mailbag from one Junior Veloso, of Singapore, who has produced this very impressive homemade photopolymer-based 3D printer. Traditional stereolithography uses a scanning UV laser to cure the liquid resin, one layer at a time. A DLP printer is similar, but uses a micromirror-based video projector to expose each layer, as shown in the diagram. Junior’s version exposes each layer for four to eight seconds, resulting in print times on the order of several hours. The resin has to be opaque to prevent “shadowing” from light transmitted through the printing layer.

Continue Reading Sean Michael Ragan11

Programmable blobs

Blob Motility is an attempt of actuated shape display using fluid programmable matter. We have developed an environment where we can program the shape of gel geometrically and topologically using our unique magnetic fluid called pBlob. This enables us to experience organic shape changes in real space, like a metaball in the CG world. The […]

Continue Reading John Baichtal