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Science

New Class of "Non-Joulian" Magnets Change Volume In Magnetic Field 39

Zothecula notes an announcement from the University of Maryland saying they have developed a new class of magnets, called "Non-Joulian" magnets, which physically expand in the presence of a magnetic field. "In the 1840s, physicist James Prescott Joule discovered that iron-based magnetic materials changed their shape but not their volume when placed in a magnetic field. This phenomenon is referred to as "Joule Magnetostriction," and since its discovery 175 years ago, all magnets have been characterized on this basis." Another significant property of these new magnets is that they can harvest or convert energy with very little waste heat (abstract). The magnets are created when thermally-treated, iron-based alloys are heated in a furnace, then rapidly cooled. When they reach room temperature, they have an odd, almost cellular shape on the microscopic level. The researchers say the magnets have numerous applications for energy-efficient sensors and actuators.
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New Class of "Non-Joulian" Magnets Change Volume In Magnetic Field

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  • by Anonymous Coward on Friday May 22, 2015 @10:56AM (#49751735)

    sure, we lose money on every magnet we produce and sell, but we make it up on volume.

  • by pushing-robot ( 1037830 ) on Friday May 22, 2015 @11:04AM (#49751809)

    Now for a Jamming Gripper [cornell.edu] that works...in space!

  • by konohitowa ( 220547 ) on Friday May 22, 2015 @11:48AM (#49752239) Journal

    According to the articles, the alloy isn't particularly exotic and the processing isn't difficult. I'd love to know what they specifically used. Sadly, they published in Nature. So I can view the paper for $5 or download as PDF for $32. Or, you know, subscribe for $200. What I don't get is why I, as one of the millions of taxpayers that funded this research, don't have free access to the paper.

    Yes. I know. Preaching to the choir, OA journals, etc. That still doesn't change the fact that I find this both irritating and wrong.

    • by ceoyoyo ( 59147 )

      Go to a library.

      • by konohitowa ( 220547 ) on Friday May 22, 2015 @12:26PM (#49752637) Journal
        When you say "go to a library" you are implying that everyone has access to a University library or similarly large, well-funded location. Not all libraries have access to journals. Although I don't have a reference for this, I suspect that the vast majority of libraries don't. I'm fortunate in the fact that I can spend an hour of total travel time (granted, 20 minutes of this will be spent waiting for the train) to get to a major University. I envision that one day there will be a series of tubes that give us access to this type of information from nearly anywhere and not a severely limited number of physical locations.
        • I envision that one day there will be a series of tubes that give us access to this type of information from nearly anywhere and not a severely limited number of physical locations.

          Yeah, but then they'll charge access for it, and the copyright cartel will insist we're not allowed to see anything without paying them a trillion dollars.

          Hey, wait a minute ... that's exactly what we have now.

        • It's available in all libraries, you just have to know where to look. They're down in the cellar, in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying 'Beware of the Leopard'.

      • by lgw ( 121541 )

        Go to a library.

        What century are you living in?

        The results of publicly funded research must be made publicly available, in a manner appropriate for the current century.

        • Todays library is called The Pirate bay.

          • by lgw ( 121541 )

            Can you actually find torrents for academic journals? That would be quite a public service by whoever's taking the time to scan them.

        • by ceoyoyo ( 59147 )

          OMG, I can't leave my basement! Everything MUST come to me in a form I consider most convenient!

          If you go to an appropriate library they have computers on which you download academic journals (funded by your tax dollars even!). If you go to the wrong library, they might have to order a paper copy for you, but paper does have a long and glorious history. Embrace it!

          Or you can read the open access journals. Just don't, uh, believe everything you read. Or you can wait the six months until the authors have

    • by GameboyRMH ( 1153867 ) <gameboyrmh@@@gmail...com> on Friday May 22, 2015 @12:53PM (#49752913) Journal

      Aaron Swartz thought the same thing...

    • by cyn1c77 ( 928549 )

      What I don't get is why I, as one of the millions of taxpayers that funded this research, don't have free access to the paper.

      Yes. I know. Preaching to the choir, OA journals, etc. That still doesn't change the fact that I find this both irritating and wrong.

      You don't get free access because the authors chose not to post a preprint/author's draft online and also chose not to submit to an open access journal. Why not pay the $35 and then deduct it from your taxes? :)

      Frankly, I'd be more pissed about how you also don't have free access to the Trans-Pacific Partnership agreement.

    • What I don't get is why I, as one of the millions of taxpayers that funded this research, don't have free access to the paper.

      Costs are public, profits are private.

      That's a compromise reached after raw capitalism's "costs are someone else's problem" resulted in near-collapse of the entire system. The problem is, it's impossible to calculate the ultimate costs of any action (install automation? That causes layoffs, which causes poverty, which causes crime, which caused the hit-and-run that killed your cousi

      • so we maintain a public fund - state budget - which pays for them, and which everyone is forced to pay to according to their ability, which we call taxes

        ...which almost everyone is forced to pay according to their inability to avoid* them...

        *In the form of paying for lawyers, accountants and legislators to facilitate avoiding them.


        The rest of your post is right on the money. I stay awake a lot of nights wondering what the other side of that phase transition from capitalism will look like. Obviously,

  • Deducing Fe-Ga (Score:5, Interesting)

    by konohitowa ( 220547 ) on Friday May 22, 2015 @12:00PM (#49752363) Journal
    Looks like I can deduce Fe73.9–Ga26.1 from one of the images [nature.com] attached to the abstract [nature.com].
  • ...non-Joulian magnets, how do they work?

Every nonzero finite dimensional inner product space has an orthonormal basis. It makes sense, when you don't think about it.

Working...