High-temperature superconductor (Yttrium barium copper oxide) floating in the magnetic field of Neodymium magnets. This phenomenon is called the Meißner-Ochsenfeld-Effect and was discovered in 1933. The superconductor has to be cooled with liquid nitrogen which has a temperature of 77 K or −196 °C. If it is placed in a strong magnetic field it remains in its position. It also works if you turn the track upside down
But this video of Penn State’s Breazeale nuclear reactor “pulsing” is the first time I’ve ever seen any moving pictures of the phenomenon, which are somehow way more impressive. And since this is a phenomenon few of us will ever have an opportunity to witness first-hand, the 15 seconds it takes to watch the video definitely count as time well spent in my book. Note how the blue glow persists for some time after the reactor itself has been shut off.
Really amazing. What’s going on in this cool time-lapse video from Italian YouTuber wwwperiodictableru isn’t a chemical reaction per se–it’s not oxidation or some other type of traditional corrosion. Turns out metallic or “white” tin spontaneously changes its so-called alpha crystal structure at temperatures below XX to the crumbly beta structure of “gray” tin. It’s the same stuff before and after–just different allotropes of the same element. The transformation, known as “tin pest” (Wikipedia), catalyzes itself–once it starts it just gets faster and faster.
As a man with a degree in philosophy, another degree in chemistry, and three engineers in my immediate family, I have to admit this strip from Zach Weiner of Saturday Morning Breakfast Cereal pretty much hit me right between the eyes. [Thanks, Matt Mets!]
So I don’t want to go too far down the “funny warning signs” rabbit hole (you could get a whole blog out of that, I think), but a commenter on last Tuesday’s “Big Scary Laser” warning sign post linked to this design, of hers, for a warning sign to go on robotic power tools. I get a huge kick out of the giant menacing robot with the buzz-saw hand. [Thanks, Jennifer!]
On Wednesday morning, Evan Ackerman over at BotJunkie posted about MIT’s Flyfire system. The idea behind the system is simple and very exciting: Swarms of tiny LED-carrying robot helicopters arrange themselves in the air to make 2D or 3D displays in which each bot serves as a single pixel. Evan linked to the project’s homepage on MIT’s SENSEable City Lab server and embedded a video posted by the group to YouTube showing the individual prototype swarmbots, which already exist, and some computer renderings of what the working displays would look like. Exciting, eh?
Accidental blindness has never been so funny! You can download a high-res version from the always-entertaining Mike’s Electric Stuff. [via Boing, which is to say Boing]
