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Joined 1 year ago
Cake day: June 26th, 2023
  • thefartographer@lemm.eetoScience@beehaw.org•New nanogenerators offer 140x power density, could replace solar cells
    5·
    19 days ago

    Okay, I’m gonna try my best here, but first a disclosure:
    I am not a scientist nor engineer or whatever. I’ve been recognized and won some awards for a class I created teaching about solar panels to young kids, but this is with no formal background. I’m going to make some assumptions about the new technology being discussed, which could be wrong. I’m going to make some comparisons to photovoltaics, which could also be wrong. I’m trusting that the researchers who told me that I explained solar cells correctly weren’t lying to me.

    I apologize in advance if this comes off like an elia5, but that’s the youngest age I taught this shit to, so I’m just falling back into old habits.

    Solar cells, while relying on a lot of really cool molecular properties can be broken down into over-simplified kinetic mechanisms. Solar cells at their most basic three components are: a material which is relatively negatively charged, a material which is relatively positively charged, and a material that allows for the flow of electrons under the right conditions.

    Electrons are these tiny parts of the stuff that makes up everything. They’re like a dot in space, sometimes attached to atoms, sometimes just flying around looking for something to attach to. They’re negatively charged and try to find places or things that are more positively charged than themselves kinda like how the negative pole of a magnet tries to find the positive pole of a magnet.

    To make a solar cell generate electricity, you have to hit it with the right kind of light. Light is one of those tricky things that can exist as both a particle and a wave. Particles of light are photons, and photons are a lot like electrons in that they’re a dot in space, just flying around, looking to crash into stuff! Sometimes they crash into a surface, or bounce off and then crash into. your eyeballs and that’s how you see things.

    If you could imagine photons and electrons as steel marbles, you can imagine what would happen when a photon hits an electron: it can cause the electron to move! But electrons don’t really like to move unless they have somewhere to go. If you roll one marble at another, you’ll never get the second marble moving quicker than the first. But consider that the electron marbles don’t love being close to each other, just like when you hold the same poles of two magnets next to each other. So, when you hit your first negatively charged material with photons, you can get some electrons to fly off of it! Especially if you hit it hard enough.

    But if you put that negatively charged material inside of something that makes it a little bit harder for the electron to move, when it gets hit by a photon, it might move a little, but it won’t actually leave because moving is hard and it has nowhere to go. Now, if you add a relatively more positively charged material to this setup, any electrons that move a little have somewhere else to go! So, if you hit the electrons just hard enough, they’ll fly off the negative material and shoot at the positive material!

    What’s really cool is that because the electron is kinda stuck on the negative material, but attracted tot he positive material, you can actually get the electron to move with quite a bit more energy than you’d expect! Even cooler than that is if you have something near the materials that conducts electricity, like a wire, you can get the electron to hit other electrons in the positive material and that pushes a chain of electrons forward just hard enough that you generate a voltage!

    If you’d like to see this for yourself, here’s a really cool experiment you can do at home:

    1. Get some copper flashing and cut two pieces of it.
    2. One of the pieces, leave it just as it is. The other piece, heat it on an electric stove top at high temperature. I mean really heat it. Let it cook until it turns deeper red and even beyond that until it gains a black film. Keep going a little longer until some of the black film start to flake and jump off of the copper flashing. That black film means you’ve oxidized the copper and made it more negatively charaged than regular copper.
    3. Now, wash your oxidized copper with soap and water, trying to scrub off as much of the black film as possible without scrubbing off the red stuff underneath it.
    4. Fill a clear container with VERY salty water, then place each piece of copper on opposite ends of the container.
    5. Attach alligator clips jumper wires to the pieces of copper and read the voltage with a voltmeter. You’ll notice a very very small charge!
    6. Shine a really bright light on your setup and you should see the voltage go up a little. Try taking the setup outside into direct sunlight and see it go up a little more! Congratulations, you’ve made a rudimentary photovoltaic cell!

    Finally, let’s equate this to the new technology:
    On a dry day, try wearing socks and rubbing them on some carpet and then touch a doorknob—you should feel a shock! This is static electricity. Rubbing the socks on the ground builds up extra electrons in your body just like the negatively charged part of a solar panel. The doorknob is like the relatively positively charged part. The air is like the salt water or material that only lets electrons flow under the right conditions. In this instance, the right conditions are touching the negative and positive parts to each other. This is a very different setup, but similar concept to how photovoltaics works.

    It sounds like this new technology works like this but on a much smaller scale. Your movements causes part of the material to build up static electricity and become negatively charged. Once you’ve built up enough extra electrons and (I think) bend the technology in the right way to get the relatively positively charged side close to your static electricity side, the extra electrons jump from one material to the other, generating a charge!

    In a really really REALLY roundabout way, it’s all exactly the same as solar technology except that all the parts are different, there’s a different catalyst, your energy input and voltage differentials are completely different.

    You know what? It’s not similar at all, but I think I get what they’re going for.

  • thefartographer@lemm.eetoWorld News@beehaw.org•Iraq Proposes Law To Reduce Legal Age Of Marriage For Girls To 9
    6·
    1 month ago

    Why are y’all making me do your research for you?

    Also, you put that text in quotes, but I don’t see it anywhere in that page, which is very misleading to do.

    It’s literally stated within the summary of the page; third paragraph from the bottom.

    That’s contradicted by the link content.

    Try clicking the links within the content to see if maybe you’re missing some context.

    Michigan

    The name of the state is hyperlinked, click on it and you’ll find section of the Michigan Legislature contains statutory age limits on marriage. The site linked from my quote is out of date because the minimum age is now 18. This is an absolute win and something to be celebrated, it just sucks that it took until 2023 to bump the age up and remove a judge’s ability to enter a child into marriage. I considered editing my quote to cross out Michigan, but that seemed dishonest. Can’t really win either way, apparently.

    Mississippi

    Let’s click the name of this state and we end up at a summary page with a specific comment:

    Minors under minimum age may obtain license with parental consent and approval of court. Minor females age 15 yrs. and older and males 17 yrs. and older but under 21 may obtain license with parental consent and court order.

    But since we’re “doing our own research” (you’re welcome), let’s not trust the content on a third party site and instead look up the listed section of the Mississippi code dealing with conditions of issuing a marriage license in which we find that

    If the male applicant is under seventeen (17) years of age or the female is under fifteen (15) years of age, and satisfactory proof is furnished to the judge of any circuit, chancery or county court that sufficient reasons exist and that the parties desire to be married to each other and that the parents or other person in loco parentis of the person or persons so under age consent to the marriage, then the judge of any such court in the county where either of the parties resides may waive the minimum age requirement and by written instrument authorize the clerk of the court to issue the marriage license to the parties if they are otherwise qualified by law.

    Same info! They’re not lying! Wait… That’s bad news. Damnit!

    There appears to be an amendment that I can’t tell if it’s passed or not, but it only raises the minimum age of girls (15) to that of boys (17). I refuse to say “men” and “women” because 17 is still a child.

    Washington

    Great news! Two months ago, Washington passed a law eliminating marriage of minors! I genuinely had no clue about this one. Obviously, the site wouldn’t have this update, but there you have it.

    Anyway, there you have it. The info you could’ve read for yourself, but chose not to before declaring yourself a victim of misinformation.

    HAVE A GREAT WEEKEND!