Why graphene hasn't taken over the world...yet

As long as they don't make ropes of graphene and have a 200,000-person tug of war, I'm all good with most uses of graphene.

The idea of mixing graphene in with ink and printing circuits on fabric seems pretty outstanding to me. I love the image of clothing that could include its own circuitry and would be fully durable no matter how we treat it.

What is the NEW Silver Play Button REALLY made of?!

The video description doesn't remotely need that ?! at the end.

That being said, the process that the youtubers here go through to find out what specific elements are in the 'silver' play button is fascinating. The (?) Energy Dispersive X-ray Spectrometer is something that's new to me.

I'm particularly fascinated by the results at 5:39 showing the elemental makeup at various depths of the 'button.'

Yeah, all that's interesting, but what's the 'gold' play button award made of? And what's beyond the gold button?

Your old phone is a veritable gold mine

Honest question - how do I make sure my data is cleared from the electronics before I let them be recycled?

The most stunning fact in this video - recovering metals like gold from e-waste is now more efficient than digging it up from the Earth.

But it makes sense if the facts (1:40) are true. If a typical gold mine has 5-6 grams of gold per ton of Earth and a ton of mobile phones (typical e-waste) contains 350 grams, that's a brilliant source of gold.

Now we just have to find ways to get to the gold.

Notice the 'nothing you do to gold does anything to it (I'm paraphrasing, admittedly)' fact? That's because it's really low on the activity series. It's a noble metal.

Oh, and the fact that we haven't ratified the Basel Convention reminds us that the US is an awful global citizen. From wikipedia, "The 10 UN member states that are not party to the treaty are East Timor, Fiji, Grenada, Haiti, San Marino, Solomon Islands, South Sudan, Tuvalu, United States, and Vanuatu."

Quenching Steel: Understanding The Why's and Wherefore's

(Edit: 6/28/21 I can't find another upload of this video. The channel that hosted it is still there, but this video seems to have disappeared. I'll check again and hope that Trent brings the video back.)

Trent's back!

Honestly he never left, but I didn't look any further into his videos than his "Moronic Jet Fuel 9/11 argument" video.

Turns out he has more to tell us...

This video goes through differences of oil versus water quenching...what quenching does to the steel of the blade (with an interesting to a latex glove as an analogy to the quenched steel)...and comes to the final lesson, "if you do not know what steel you are dealing with, you will not know how to properly quench it or harden it or temper it"...

He does, I warn you, use the word 'retard' again at about 0:28 - the "new samurai retard squad". C'mon, Trent, spread the word to end the word.

What quenching and tempering does to SWORDS

Trigger warning: Aussie accent...keep hacky comedians and actors away lest they start doing the Philosophers song.

There's a whole bunch of high-quality explanation in this one...

• 1:19 - percentage breakdown of carbon in various steels (low carbon, medium carbon, high carbon)
• 1:49 - "When the iron is hot...reaches the austenite phase...lost magnetic interaction...body centered cubic or face centered..." Honestly, he screws up the crystals verbally (though the graphics are correct) but does nicely say that "there's more room in between the iron atoms when it's this hot which means carbon atoms can all fit around evenly wherever they want" and that "when iron is cool...they try and squeeze out the carbon in between these iron atoms" and shows ferrite in the graphic
• 2:56 - micrograph of ferrite and cementite as the carbon in squeezed out from between the iron atoms, making pearlite
• 4:16 - Say "crystals" not "structure", man...c'mon
• 4:44 - discussion of work hardening and how that's lost once the metal is reheated, "it loosens the insides. It basically gives the opportunity for the stresses to be released and moved around and become uniform...as soon as you heat it up, you're losing whatever benefits - but also detriments - you might've put into the steel"
• 8:16 - "When heated up to where austenite is formed in the steel, the carbon is not forced into these veins/pocket/lines...and if you were to cool it down rapidly, you can actually give those iron atoms not enough time to force [carbon] out into these more condensed pockets...and a different, amazing crystalline structure is formed within the steel called martensite"
• 9:40 - "[Martensite] can be very useful to swords because you want swords to have a very hard edge, but you don't want them to be too brittle"...Goldilocks of metals, eh
• 10:05 - how the Japanese solved the problem, great diagram of the anatomy of a samurai sword (ion core, pearlite jacket, martensite edge) created via clay control of cooling rate
• 11:50 - tempering makes its appearance...we've been waiting, Shad
• 12:30 - showing quench of a katana with differential cooling causing bending in both directions (flubbed vocals but corrected captions)
• 13:10 - "[tempering] releases stress between these dislocations creating a much greater level of ductility and flex in between the crystal structure that's being formed within it" - nice micrographs of martensite and tempered martensite
• 15:00 onward...what makes for a good sword, particularly its sharpness...not so much material science