This video covers ground that is more attractively covered in this other unit cell video.
...but this video also goes through the specific math required to calculate the packing factor - the percent of occupied space - for each of the crystal structures.
Plus it has a Pokemon analogy - which the computer animation video doesn't have.
To paraphrase Corey Petersman, an AP chemistry and material science student during our first year of teaching matsci at Princeton, "vaporeon, witches!"
I've never been to the Pacific Northwest - not further north than the Redwoods National and State Parks in Northern California, anyway.
Might have to get to the Tacoma/Seattle area to check out the Museum of Glass.
This video is an un-narrated walking tour of that museum with occasional annotations in the top corner of the video. Not a ton of information - certainly no science - just glances at pretty glass.
I've said it before, but an atomic trampoline demonstration set-up would make for a spectacular gift for your favorite neighborhood blogger.
NileRed took a different route than I've taken - which is mostly just wishing that I would stumble across an atomic trampoline and not really doing anything at all to make that happen - and decided to make a disk of amorphous metal on his own.
Admittedly, one of our ASM Master Teachers has a lead on getting sets of amorphous metal disks for us to have in our classrooms. It involves the material scientists at Apple's headquarters in California and turned out to be much more complicated than expected because - as NileRed finds out - the adhesive used to affix the amorphous metal to the steel base is highly relevant in maintaining the ridiculously bouncy nature of amorphous metals in this application.
Here's to hoping that my strategy of doing nothing and just hoping things will work out will...um...work out.
I'll include the Grand Illusions videos that inspired Steve Mould's video that in turn inspired NileRed's above video...
I love that this is a week-long research project/workshop for high school seniors. I know that we don't do anything nearly that intensive in our material science course at Princeton - partially because of time constraints and partially because we don't have anything that would test concrete's compression strength with any accuracy.
Does anybody know of similar experiences that near you that we could recommend for our high school students?
At some point in my material science and chemistry courses, I speak bluntly to my students that most research suggests that man-made polymers are bad for us.
Some are worse than others, but most research on the effects of polymers on humans seems to suggest that there are bad effects from most man-made polymers. Some are minorly bad, but others - like the family of PFAS - are more obviously and persistently bad.
The video above is short and has a direct message: DuPont is bad (or has acted badly).
The longer video below - from Veritasium - is far longer but is much, much more informative.
If this sounds familiar, you might've seen a semi-recent movie about this story, Dark Waters.
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| Source - Recyclingedu |
But scientists from the University of Amsterdam claim to have found a way to separate cotton from polyester and leave both as usable, recyclable products. The process seems chemically simple, soaking the blended fabrics in concentrated hydrochloric acid so that the cotton decomposes into glucose - which can be used as a monomer for further repolymerization - and leaving the still-polymerized polyester to be reformed into fabric.
Sounds great to me. Hopefully it'll be scaleable, because - as quoted in the article...
Textile production is responsible for 10% of global carbon emissions, more than international flights and maritime shipping combined. This new method could reduce emissions, conserve resources, and lessen our dependence on virgin materials by making recycling easier and more efficient.
Seven or so years ago a non-profit group known as The Ocean Cleanup launched System 001 (aka Wilson) into the Pacific Ocean to begin cleanup on the Great Pacific Garbage Patch, a high-concentration 'soup' of plastic between Hawaii and the Western Coast of the United States.
Initial results were - by their own description - promising, though they did have some "unscheduled learning opportunities" leading to the creation of System 001/B then on to System 002 (aka Jenny).
If you're a long-time blog follower, you might be wondering if this isn't a repeat posting, but it's not.
I did previously post a video titled How NASA Reinvented The Wheel - Shape Memory Alloys, but that one was by Brian at Real Engineering.
The topic are largely the same, though this one goes more deeply into how NiTiNOL works on the stress-strain curve and how the deformation of NiTiNOL is an autenite to twinned martensitic crystal transformation - complete with some nice animations.
It does also mention that the crystal transformation are exo- and endothermic (17:05), something that I don't think I've seen mentioned in other videos. I admit that if hot water is necessary for the martensite to austenite transition, it must be endothermic, but I haven't seen anything demonstrating that transition being both noticeable with bare hands - and a large enough NiTiNOL sample - or via thermal imaging camera. Neat detail there, doctor Derek.
I'm a fan of I'm With Her. In fact, I have tickets for their concert in Cincinnati on July 11. Great harmonies, great musicianship, loads of fun from three songwriters with great voices. Check out this live performance
That's neither here nor there for today's video, however, as it's focused on the production of the vinyl for their first album. Initially the grooves are carved in a thin lacquer on an aluminum disk to make a master. The disk is then metallized with a thin coating of aluminum which is then copied as another metal disk to create a mother - another metal disk which is then used to make the actual vinyl records.
I'll admit that the general idea - make a positive to make a negative to make a whole bunch of positive copies - is fairly straight forward, but I've never seen the specific process for vinyl records.
Stick with me, folks.
I wouldn't normally turn to Fox News for my science reporting, but their story does the best job - of the ones I quickly searched on YouTube - of explaining the Kopp-Etchells effect in which the edges of helicopter rotor blades get abraded via airborn grains of sand, sending showers of pyrophoric tittanium-nickel alloys into the air and making for a lovely light show - that admittedly shortens the lifespan of the blades and advertises the presence of the helicopters at night.
Effectively, it turns the edges of the blades into sparklers.
It makes for some really pretty pictures, though...
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| Source - reddit |
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| Source - wikipedia |
Here's another video with a little more science presented in meme-ified format.
As promised last week, here's the first Veritasium video about thermite.
I'm not thrilled that Dr Derek's titles seem to be getting more clickbaity and less informative. Again this week, the video's title isn't really what the video is about. It's a minor part of the video - here addressed in about six minutes in the middle of the video - and doesn't really cover the bulk of the video's content.
With that being said, seeing thermite in slow motion and through glass is pretty stunning.
Great video...bad title...
The title of this video - which might change since I'm writing this up just a day after it was posted to YouTube - is a bit misleading. The actual question in the title - why don't railroads need expansion joints - is only answered in the last half minute or so of the video and is answered more thoroughly in a Practical Engineering video that I'll post after a jump.
The bulk of the video is spent explaining how railroad welds using thermite work. The video explains the nuances far better than other thermite videos I've posted before, explaining why the rails must be aligned and peaked, why the rails must be preheated (including a nice demonstration of heat treating), how the crystal structure changes as a result of the weld, and eventually why the rails don't need expansion joints.
This is the second of at least three thermite videos from Dr Derek. I thought I'd posted the first video to both blogs, but I can't seem to find it, so it'll likely show up next week.
I'll admit that I entered the giveaway to hopefully win one of NileRed's atomic trampolines.
No luck, though, so I'll only be able to show the video.
An atomic trampoline is really high on my matsci wish list, though. I want one so desperately.
I certainly watched this NileRed video and came to the conclusion that I'm a lot of money and skills away from making one myself.
I do want Destin to get back to making shorter videos like his initial, six-and-a-half-minute Prince Rupert's drops video, but I understand that he's just working to optimize for the algorithm.
At least the Smarter Every Day videos are quality videos from tip to tail, showing brilliant views and asking questions along the way of the entire manufacturing process.
I learn so much from all of Destin's videos.
And I'm going to get myself some of those MVP discs.
Sprechen sie deutsch?
Ja, aber nur ein bisschen.
In case you don't speak German, the ZEISS folks have provided handy captions so Toni can take us on a bit of a tour to show what a metallographer does.
I will say that there are some metallographers in the world who don't necessarily use exclusively ZEISS microscopes, though, in spite of what this video shows.
#forbiddenfrosting
Most hand manufacturing processes are stunning to watch, and in this case it apparently produces a product that is superior to mass manufactured competitors. It has to be way more expensive and time-consuming, though.
So pretty...so mesmerizing...so colorful...
This video was published by Adam Ragusea in November 2024 about a study from a month or so earlier than that.
The tl;dr of the study is that many black plastics are produced from recycled black plastics that are frequently sourced from electronic waste which contains higher amounts of particularly toxic, flame-retardant chemicals. Those 'new' black plastic items could - especially if used in high heat areas like food flippers and turners on the stovetop - release higher than safe amounts of those chemicals.
In the above video, Adam goes through the possible concerns that this raises as well as noting a possible math error in the study's calculations suggesting that the level of concern is slightly lower than the authors might have initially suggested.
The article was corrected - noting exactly the math error that Adam suggested, and Adam published a spectacular video explaining why that error should not undermine faith in the scientific process or even in the researchers and authors of the original article.
