More on AI Learning


It’s as if they read my mind, or something…

After my recent admission that I once stuck a cinnammon red hot up my nose, it was kind of awkward to see that the manufacturer of a ferrofluid toy had thought of me, specifically.

Honestly, it hadn’t even occurred to me that this might be a problem, but I suppose that if you swallowed some ferrofluid and went for an MRI, you’d make a horrible mess of their expensive machine. Thriller-writers, take note: there’s a murder plot hidden in there.

I have a few ultra-powerful magnets and fortunately I have very strong hands; when they slip out of your fingers they’re going to get together no matter what. I wanted to make some ferrofluid ‘slime’ (polyvinyl alcohol and borax and black iron oxide) and my first experiment with the slime was nowhere near as interesting as I hoped it would be, although it was pretty cool to have a very messy-looking substance that sucks right off your finger and vanishes to re-appear on a magnet a few inches away. Some of this stuff is difficult to photograph single-handed because it involves setting up a bunch of elaborate tech: lights, camera tethered on laptop with timing trigger, ultra-macro lens, supporting rail. Technical photography can be a real drag unless you’re into it and you get the right moment: then it’s magic.

I didn’t take the time to really set this up carefully; I just ran down to the kitchen (isn’t that where you keep your ferrofluid?) and played around. By the way – I don’t know if iPhones like strong magnets but I didn’t find out. Why don’t you try it with yours and let me know?

As you can see, when you scare a ferrofluid with a magnet, it gets upset, swells up, and extrudes spikes that are intended to scare away any creature that is thinking of eating it. Between its threatening spikes and nasty, crunchy taste, ferrofluids are pretty safe from predation, though. When ferrofluids get aggressive, they can make quite a mess.

I whipped up a quick batch of ferroslime and didn’t get the proportion of water to PVA solution right, so it was pretty liquid. Check out the way the magnet rips the iron oxide right out of the slime!

Cleaning this up took a while. And, since you’re basically dealing with rust you need to be pretty meticulous.

Speaking of “meticulous” – can you spot the mistake that almost happened in this picture? (spoiler is below) Hint: the spoon is stainless steel.

------ divider ------

Yeah, the beaker is glass. I realized that if the magnet slipped out of my hand, it could go right through the side of the beaker and make a really horrible mess. So: I put plastic down and was really careful. As it happened, I was careful enough.

MRIbtw: MRI machines were developed at Johns Hopkins Hospital while I was an undergrad at the university. I got the $$ for my first motorcycle by serving as a lab-rat on MRI and PET (positron emission tomography) systems. The MRI was pretty cool but the PET was a slog: they drew blood from me every 30 minutes for 2 days, and by the end of that I was pretty tired of people coming at me with a needle! But: $1,500! And a good bike cost $2,000 in those days.  My favorite thing about MRI was the all-titanium toolkit they had to work on it with. It was gorgeous; I love titanium. At the time they weren’t quite sure of all of the things that could go wrong, so they were being very careful about anything ferrous in the area.

Comments

  1. Pierce R. Butler says

    … if you swallowed some ferrofluid and went for an MRI, you’d make a horrible mess of their expensive machine. Thriller-writers, take note: there’s a murder plot hidden in there.

    Tim Dorsey’s annals of Serge A. Storms (see Torpedo Juice, chapter 2) already got that one covered – though with ferrous, ahem, particles – thanks.

  2. says

    Pierce R. Butler@#1:
    Tim Dorsey’s annals of Serge A. Storms (see Torpedo Juice, chapter 2) already got that one covered – though with ferrous, ahem, particles – thanks.

    Well, wow!

  3. says

    Oh, I have to play with that stuff! I haven’t made a massive mess in ages. Very cool!

    I get stuck in MRIs all too often. The stationary ones are fab, the portable ones, not so much. About the size of a coffin. My fave high tech med machine is the CAT, that thing looks straight out of star trek.

  4. says

    I have to play with that stuff!

    I think I sent you some. Just take about 10:1 of the slipperier gunk and add the other stuff slowly, while stirring. I included some UV dye – glowslime is pretty cool looking.

    Just don’t let the rats eat it; it’s glue.

  5. says

    Marcus:

    Just don’t let the rats eat it; it’s glue.

    Oh my, they’d love it then. Glue is one of their favourite things.

  6. says

    Caine@#5:
    Glue is one of their favourite things.

    I’m endlessly amazed by the digestive capabilities of some animals. My dogs used to eat week-old dead woodchuck and would burp happily a couple times. My horse P-nut used to love to chow down on hemlock branches – I suppose it made his tongue tingle – because he would foam and drool with a big grin on his face.

  7. says

    That is a bit runny. I usually muck up my first tries too. Do you have any plans for the magnetic goo?

    I spend a lot of time looking at MRI images and I’ve had a big fascination for what iron oxide does in the brain. It’s easy to get excited since when iron oxide shows up in the news and biology quantum effects are involved (birds and magnetic sense, bacteria and the same, primates have it in the cornea). But right now the research is mostly focused on the brain and iron metabolism gone wrong since research tends to follow medicine. There’s no settled big picture stories on what iron does but we know where it accumulates with increasing accuracy, but memory is one connection. This post prompted me to do a new search and I found a new piece of eye-candy.
    >Automated segmentation of midbrain structures with high iron content.
    http://www.ncbi.nlm.nih.gov/m/pubmed/28602813

  8. says

    Brony, Social Justice Cenobite@#7:
    That is a bit runny. I usually muck up my first tries too. Do you have any plans for the magnetic goo?

    Yeah, I made another batch, better than the bad batch, then banged and beat it and did stuff! I’ll post some tomorrow. I felt embarrassed at the terrible quality of the iphone video.

    I’ve had a big fascination for what iron oxide does in the brain

    I had no idea…
    I haven’t been particularly cautious around my powdered iron (of various forms) hopefully that’s not an “uh oh!” I generally assume that exposure to common elements is probably something we’ll have evolved to handle – aside from things like “trying to breathe water” I mean.

  9. says

    @Marcus
    A rational concern. In my experience it is not considered toxic in general handling. In fact some papers were investigating it’s use in treating tumors. I can’t say there is no risk but I can’t think of one that would require any extra safety like would be required by say osmium tetraoxide (I coincidentally have an osmium mission on Elite).

  10. bmiller says

    Awesome!

    Off Topic: Can I just say that Brony, Social Justice Cenobite, may be my favorite user name ever.

  11. says

    Marcus:

    I’m endlessly amazed by the digestive capabilities of some animals. My dogs used to eat week-old dead woodchuck and would burp happily a couple times. My horse P-nut used to love to chow down on hemlock branches – I suppose it made his tongue tingle – because he would foam and drool with a big grin on his face.

    I don’t even keep superglue in my studio anymore, they will go to any length to get it. Very little seems to be beyond a rat’s digestive capabilities. Used to have a cat that would go out to a pine tree by the front porch, get a huge mouthful of sap, then come in and jaw it down for an hour or two. Asked our vet about it, he stared at us for a few beats then said “you guys have the weirdest fucking animals.”

  12. says

    @biller
    Thank you. For genetal interest the “Brony” was meant to be bait for irresponsibility macho-types in arguments (in addition to the fandom I’m on the peripjery of) but sadly does not work as often as I thought. The rest is stealing a conservative insult and a reference to the Hellraiser horror movie series.

  13. Raucous Indignation says

    Stainless steel spoon: most stainless steels are non-magnetic or only slightly magnetic.

  14. says

    Raucous Indignation@#15:
    Stainless steel spoon: most stainless steels are non-magnetic or only slightly magnetic.

    Yep, that’s the hint: I was OK using a non-magnetic spoon but I wasn’t using “strong magnet safe” containers. I suppose I could set up my slow motion camera and record the explosion of shards you’d get when a magnet slammed into a beaker full of ferrofluid but I don’t want to clean up the mess.

  15. Reginald Selkirk says

    I just tested one spoon and one fork, from different patterns and presumably different manufacturers, both clearly marked “stainless steel”, with a handy magnet. Both adhered nicely. Some formulations of stainless are magnetic, some are not. Also I wonder if like silver plate, cheap utensils are stainless all the way through, or only on the surface.

    Laugh if you want, but magnet ingestion, mostly by children, is a real health concern.
    Magnets in the bowel: A sticky problem!
    Stronger (e.g. rare earth) magnets are available these days, and even commonplace. If a child swallows two strong magnets, they can attract each other from different chambers or folds in the digestive system, which can lead to bad stuff happening.

    Couldn’t figure out how to display this JPEG diagram, so here’s the link:
    http://ipcblog.org/wp-content/uploads/2012/12/stomach-150×150.jpg

Leave a Reply