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(12-22-2017, 04:39 PM)unclechuck link Wrote:[quote author=eric link=topic=9890.msg218919#msg218919 date=1513902852]
Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here

https://www.nature.com/articles/s41565-0...cience.com

In Jr High I remember reading some 1950s SciFi about a society of assassins who only used knives since a fast-pressure responsive fabric had been developed that completely resisted projectiles, but could be penetrated by the slow pressure of an edged weapon. My suspension of disbelief is now formally retired; thanks!
[/quote]


I think you may be referring to "The Paradox Men" by Charles Harness circa 1954.  Frank Herbert adopted a similar idea for "Dune."
(12-22-2017, 04:39 PM)unclechuck link Wrote:[quote author=eric link=topic=9890.msg218919#msg218919 date=1513902852]
Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here

https://www.nature.com/articles/s41565-0...cience.com

In Jr High I remember reading some 1950s SciFi about a society of assassins who only used knives since a fast-pressure responsive fabric had been developed that completely resisted projectiles, but could be penetrated by the slow pressure of an edged weapon. My suspension of disbelief is now formally retired; thanks!
[/quote]


I think you may be referring to "The Paradox Men" by Charles Harness circa 1954.  Frank Herbert adopted a similar idea for "Dune."
"Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here"

I'm always a bit dubious about claims made in publications from scientist looking for more funding (all scientists including me).  When one talks about impenetrability, you're talking about "toughness" or strength not hardness.  Diamonds are hard because of their crystalline structure that includes conjugated (alternating with single bonds) double bonds arranged in a crystalline lattice.  Materials like this can be very hard, but because of their crystallinity, can also be brittle.  Diamonds can be easily cleaved.  As far as I know, the strongest, toughest, most impenetrable material is elongated polyethylene, basically the same stuff that's in plastic bags, but in a higher molecular weight version.  This is because the polyethylene's molecule's backbones are held together by carbon-carbon single bonds, some of the strongest atom to atom bonds known.  Honeywell makes a version of this tradenamed "Spectra".  Many people think that Kevlar (DuPont tradename) is the strongest material around, but elongated high molecular weight polyethylenes are considerably stronger.  An interesting application of this material is for hawsers or ropes for tying up large ships since the volume and weight of the ropes on ships is significant.  It is also used for the more obvious applications like bullet-proof vests and helmet liners.  I have a business acquaintance who makes bullet-proof vests and had a promotional film made of his being shot wearing one.  He was literally standing behind his product.  He's also nuts.
"Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here"

I'm always a bit dubious about claims made in publications from scientist looking for more funding (all scientists including me).  When one talks about impenetrability, you're talking about "toughness" or strength not hardness.  Diamonds are hard because of their crystalline structure that includes conjugated (alternating with single bonds) double bonds arranged in a crystalline lattice.  Materials like this can be very hard, but because of their crystallinity, can also be brittle.  Diamonds can be easily cleaved.  As far as I know, the strongest, toughest, most impenetrable material is elongated polyethylene, basically the same stuff that's in plastic bags, but in a higher molecular weight version.  This is because the polyethylene's molecule's backbones are held together by carbon-carbon single bonds, some of the strongest atom to atom bonds known.  Honeywell makes a version of this tradenamed "Spectra".  Many people think that Kevlar (DuPont tradename) is the strongest material around, but elongated high molecular weight polyethylenes are considerably stronger.  An interesting application of this material is for hawsers or ropes for tying up large ships since the volume and weight of the ropes on ships is significant.  It is also used for the more obvious applications like bullet-proof vests and helmet liners.  I have a business acquaintance who makes bullet-proof vests and had a promotional film made of his being shot wearing one.  He was literally standing behind his product.  He's also nuts.
I’m a bit confused.  I thought all the bonds in diamond were carbon-carbon single bonds (each carbon bound to four others in a tetrahedral arrangement).  It was graphite, I thought that had alternating single and double bonds, with one carbon attached to three others in a planar hexagonal pattern, making graphite fairly strong in one direction (perpendicular to the plane), but easily cleaver between planes.

BC
I’m a bit confused.  I thought all the bonds in diamond were carbon-carbon single bonds (each carbon bound to four others in a tetrahedral arrangement).  It was graphite, I thought that had alternating single and double bonds, with one carbon attached to three others in a planar hexagonal pattern, making graphite fairly strong in one direction (perpendicular to the plane), but easily cleaver between planes.

BC
(12-23-2017, 07:35 AM)Mick link Wrote:[quote author=unclechuck link=topic=9890.msg219026#msg219026 date=1513985999]
[quote author=eric link=topic=9890.msg218919#msg218919 date=1513902852]
Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here

https://www.nature.com/articles/s41565-0...cience.com

In Jr High I remember reading some 1950s SciFi about a society of assassins who only used knives since a fast-pressure responsive fabric had been developed that completely resisted projectiles, but could be penetrated by the slow pressure of an edged weapon. My suspension of disbelief is now formally retired; thanks!
[/quote]


I think you may be referring to "The Paradox Men" by Charles Harness circa 1954.  Frank Herbert adopted a similar idea for "Dune."
[/quote]

Mick - you nailed it! Paradox Men was the one I was thinking of. Thanks, will now chase that down for a re-read and see how it holds up. Cheers.
(12-23-2017, 07:35 AM)Mick link Wrote:[quote author=unclechuck link=topic=9890.msg219026#msg219026 date=1513985999]
[quote author=eric link=topic=9890.msg218919#msg218919 date=1513902852]
Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here

https://www.nature.com/articles/s41565-0...cience.com

In Jr High I remember reading some 1950s SciFi about a society of assassins who only used knives since a fast-pressure responsive fabric had been developed that completely resisted projectiles, but could be penetrated by the slow pressure of an edged weapon. My suspension of disbelief is now formally retired; thanks!
[/quote]


I think you may be referring to "The Paradox Men" by Charles Harness circa 1954.  Frank Herbert adopted a similar idea for "Dune."
[/quote]

Mick - you nailed it! Paradox Men was the one I was thinking of. Thanks, will now chase that down for a re-read and see how it holds up. Cheers.
(12-23-2017, 02:02 PM)unclechuck link Wrote:[quote author=Mick link=topic=9890.msg219046#msg219046 date=1514039701]
[quote author=unclechuck link=topic=9890.msg219026#msg219026 date=1513985999]
[quote author=eric link=topic=9890.msg218919#msg218919 date=1513902852]
Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here

https://www.nature.com/articles/s41565-0...cience.com

In Jr High I remember reading some 1950s SciFi about a society of assassins who only used knives since a fast-pressure responsive fabric had been developed that completely resisted projectiles, but could be penetrated by the slow pressure of an edged weapon. My suspension of disbelief is now formally retired; thanks!
[/quote]


I think you may be referring to "The Paradox Men" by Charles Harness circa 1954.  Frank Herbert adopted a similar idea for "Dune."
[/quote]

Mick - you nailed it! Paradox Men was the one I was thinking of. Thanks, will now chase that down for a re-read and see how it holds up. Cheers.
[/quote]

Happy Holidays to you, as well.  I read Paradox Men and Dune back to back in high school; I thought they were both entertaining reads, though I enjoyed Dune quite a bit more.

I had a Science Fiction class in 1981 -- my frosh year -- and I still remember our professor's opening statement, to wit: "98% of all science fiction is absolute dreck.  The remaining 2% will be the best fiction you'll ever read."

I don't remember the entire syllabus, but we had to read a book every other week.  I recall The Stars My Destination, A Canticle for Leibowitz, Man in a High Castle, and an anthology with an amazing short story written by Isaac Asimov in 1941 when he was a chemistry grad student called "Nightfall."  To my 17 year old self, it was electric.  It answered the question, "What if a planet only experienced nightfall once every millenium?" (because said planet had five or six suns, I can't remember which).
(12-23-2017, 02:02 PM)unclechuck link Wrote:[quote author=Mick link=topic=9890.msg219046#msg219046 date=1514039701]
[quote author=unclechuck link=topic=9890.msg219026#msg219026 date=1513985999]
[quote author=eric link=topic=9890.msg218919#msg218919 date=1513902852]
Scientists Discover Process for Transitioning Two-Layer Graphene into a Diamond-Hard Material on Impact

The innovation could enable development of a range of flexible, impenetrable materials capable of protecting the body and fragile objects

http://www.asrc.cuny.edu/2017/12/18/diamene-study/

the paper is here

https://www.nature.com/articles/s41565-0...cience.com

In Jr High I remember reading some 1950s SciFi about a society of assassins who only used knives since a fast-pressure responsive fabric had been developed that completely resisted projectiles, but could be penetrated by the slow pressure of an edged weapon. My suspension of disbelief is now formally retired; thanks!
[/quote]


I think you may be referring to "The Paradox Men" by Charles Harness circa 1954.  Frank Herbert adopted a similar idea for "Dune."
[/quote]

Mick - you nailed it! Paradox Men was the one I was thinking of. Thanks, will now chase that down for a re-read and see how it holds up. Cheers.
[/quote]

Happy Holidays to you, as well.  I read Paradox Men and Dune back to back in high school; I thought they were both entertaining reads, though I enjoyed Dune quite a bit more.

I had a Science Fiction class in 1981 -- my frosh year -- and I still remember our professor's opening statement, to wit: "98% of all science fiction is absolute dreck.  The remaining 2% will be the best fiction you'll ever read."

I don't remember the entire syllabus, but we had to read a book every other week.  I recall The Stars My Destination, A Canticle for Leibowitz, Man in a High Castle, and an anthology with an amazing short story written by Isaac Asimov in 1941 when he was a chemistry grad student called "Nightfall."  To my 17 year old self, it was electric.  It answered the question, "What if a planet only experienced nightfall once every millenium?" (because said planet had five or six suns, I can't remember which).
Great selections by the prof, though nothing surprising.

Paradox Men is one I haven't heard of. I'll have to see if I can find it. I did recognize the similar idea used in Dune.
Great selections by the prof, though nothing surprising.

Paradox Men is one I haven't heard of. I'll have to see if I can find it. I did recognize the similar idea used in Dune.
Mick - may have had a similar history: nerd buddies in high school furiously swapping paperbacks while ignoring the Charles Dickens we were supposed to be reading. Took the SciFi class @ Stanford in 1970, when taught by our resident radical prof: Bruce Franklin. Syllabus was different with first half focused on classical stuff from Verne up thru the 1920s-30s; evolution of the robot meme from the traditional golem tales of folklore & Frankenstein, and iterations of dystopian visions from Victorian times forward.

He intentionally stayed away from some of the more epic works; e.g. Assimov's Foundation series or James Blish's Cities in Flight, as unsuitable due to a similar book(s) per week timeline. Also, Herbert's Dune, plus Vonnegut & Robert Heinlein were seen as contemporary and assumed to be read by folks taking the class. Still, a great survey and perspective course that I never would have worked through on my own time.
Mick - may have had a similar history: nerd buddies in high school furiously swapping paperbacks while ignoring the Charles Dickens we were supposed to be reading. Took the SciFi class @ Stanford in 1970, when taught by our resident radical prof: Bruce Franklin. Syllabus was different with first half focused on classical stuff from Verne up thru the 1920s-30s; evolution of the robot meme from the traditional golem tales of folklore & Frankenstein, and iterations of dystopian visions from Victorian times forward.

He intentionally stayed away from some of the more epic works; e.g. Assimov's Foundation series or James Blish's Cities in Flight, as unsuitable due to a similar book(s) per week timeline. Also, Herbert's Dune, plus Vonnegut & Robert Heinlein were seen as contemporary and assumed to be read by folks taking the class. Still, a great survey and perspective course that I never would have worked through on my own time.
(12-23-2017, 10:19 AM)Boston Card link Wrote:I’m a bit confused.  I thought all the bonds in diamond were carbon-carbon single bonds (each carbon bound to four others in a tetrahedral arrangement).  It was graphite, I thought that had alternating single and double bonds, with one carbon attached to three others in a planar hexagonal pattern, making graphite fairly strong in one direction (perpendicular to the plane), but easily cleaver between planes.

BC

You're quite right.  I was looking at the title graphene and simultaneously thinking diamond and conflated the two in my increasingly feeble mind.  Diamonds have all sigmatropic (single) bonding, otherwise pure diamond wouldn't be clear.  Thinking more about this, if you had very extensive sheets of graphene in each macromolecule (if that is the correct word on that scale), you might end up with quite a strong material.  While I haven't worked personally with graphene, people working next to me in the lab were.  I got the impression that the individual macromolecules are not that extensive.  If that is the case shear down through the material perpendicular to the graphene planes might cause them to sllde apart.  Graphite is quite a good lubricant, I suspect because of the this sort of reaction to shear.  The reason that a similar thing doesn't occur in high molecular weight polyethylene materials like Spectra is that the individual molecular strands are entangled with each other and cannot slide past each other.  Because the planar graphene macromolecules are very flat, they do not entangle and while there will be some interaction between planes, it will be a lot less strong than in the entangled polyethylene strands.
At any rate that's where I was trying to go in my poorly written previous post.  Also, I'm a liquid crystal guy (1-D molecules not 2-D molecules) and this whole thing is pretty rank supposition on my part.  I apologize for the confusion.
(12-23-2017, 10:19 AM)Boston Card link Wrote:I’m a bit confused.  I thought all the bonds in diamond were carbon-carbon single bonds (each carbon bound to four others in a tetrahedral arrangement).  It was graphite, I thought that had alternating single and double bonds, with one carbon attached to three others in a planar hexagonal pattern, making graphite fairly strong in one direction (perpendicular to the plane), but easily cleaver between planes.

BC

You're quite right.  I was looking at the title graphene and simultaneously thinking diamond and conflated the two in my increasingly feeble mind.  Diamonds have all sigmatropic (single) bonding, otherwise pure diamond wouldn't be clear.  Thinking more about this, if you had very extensive sheets of graphene in each macromolecule (if that is the correct word on that scale), you might end up with quite a strong material.  While I haven't worked personally with graphene, people working next to me in the lab were.  I got the impression that the individual macromolecules are not that extensive.  If that is the case shear down through the material perpendicular to the graphene planes might cause them to sllde apart.  Graphite is quite a good lubricant, I suspect because of the this sort of reaction to shear.  The reason that a similar thing doesn't occur in high molecular weight polyethylene materials like Spectra is that the individual molecular strands are entangled with each other and cannot slide past each other.  Because the planar graphene macromolecules are very flat, they do not entangle and while there will be some interaction between planes, it will be a lot less strong than in the entangled polyethylene strands.
At any rate that's where I was trying to go in my poorly written previous post.  Also, I'm a liquid crystal guy (1-D molecules not 2-D molecules) and this whole thing is pretty rank supposition on my part.  I apologize for the confusion.
Entertaining Ted talk on graphene:

[url=http://][/url]

OK, this is OT for this thread, but since it is fascinating and has nothing to do with Stanford football...

Apparently, yesterday it snowed in the Sahara desert.  The images are super cool:

http://www.bbc.com/news/av/world-africa-...ara-desert

And, dolphins are like wicked smart:

https://www.theguardian.com/science/2003...ch.science

Quote:All the dolphins at the institute are trained to hold onto any litter that falls into their pools until they see a trainer, when they can trade the litter for fish. In this way, the dolphins help to keep their pools clean.

Kelly has taken this task one step further. When people drop paper into the water she hides it under a rock at the bottom of the pool. The next time a trainer passes, she goes down to the rock and tears off a piece of paper to give to the trainer. After a fish reward, she goes back down, tears off another piece of paper, gets another fish, and so on....

But it gets better.  Kelly has figured out how to game the system even more:

Quote:One day, when a gull flew into her pool, she grabbed it, waited for the trainers and then gave it to them. It was a large bird and so the trainers gave her lots of fish. This seemed to give Kelly a new idea. The next time she was fed, instead of eating the last fish, she took it to the bottom of the pool and hid it under the rock where she had been hiding the paper. When no trainers were present, she brought the fish to the surface and used it to lure the gulls, which she would catch to get even more fish. After mastering this lucrative strategy, she taught her calf, who taught other calves, and so gull-baiting has become a hot game among the dolphins.

BC
How did I miss this article relevant to this oft-resurrected thread...

https://www.extremetech.com/extreme/2597...dium=title

Quote:According to Samsung, graphene balls can be used to boost battery capacity by 45 percent and charging speed by a whopping 500 percent.

I'm skeptical, but still.

BC
(01-23-2018, 10:50 AM)Boston Card link Wrote:How did I miss this article relevant to this oft-resurrected thread...

https://www.extremetech.com/extreme/2597...dium=title

Quote:According to Samsung, graphene balls can be used to boost battery capacity by 45 percent and charging speed by a whopping 500 percent.

I'm skeptical, but still.

BC

I guess you missed post 67........ :)

Recently, a team of researchers at the Samsung Advanced Institute of Technology (SAIT) developed a “graphene ball,” a unique battery material that enables a 45% increase in capacity, and five times faster charging speeds than standard lithium-ion batteries. The breakthrough provides promise for the next generation secondary battery market, particularly related to mobile devices and electric vehicles.

https://news.samsung.com/global/samsung-...ging-speed
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