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GRAPHENE, THE WONDER MATERIAL
nipper
post Posted: Nov 4 2019, 08:49 AM
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12-18 month trial
QUOTE
Talga (TLG) announced the commencement of a commercial-scale trial of a Talga graphene-enhanced coating applied to a 33,000t container ship.

Believed to be the world’s largest single application of graphene, the 700m2 coating of the cargo vessel’s hull is part of advanced testing of Talga’s functionalised graphene (Talphene®) additive as a performance booster for existing commercial marine coatings (part of the global 54 million tonne per annum paint and coating market).




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"Every long-term security is nothing more than a claim on some expected future stream of cash that will be delivered into the hands of investors over time. For a given stream of expected future cash payments, the higher the price investors pay today for that stream of cash, the lower the long-term return they will achieve on their investment over time." - Dr John Hussman

"If I had even the slightest grasp upon my own faculties, I would not make essays, I would make decisions." ― Michel de Montaigne
 
nipper
post Posted: Apr 13 2019, 05:56 PM
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QUOTE
A new graphene-based foam is the first material to remain soft and squishy even at deep cryogenic temperatures.

Most materials become stiff and brittle in extreme cold. But the new foam stays superelastic even when it’s subjected to the temperature of liquid helium: –269.15° Celsius. A material that remains pliable at such low temperatures could be used to build devices for use in space, researchers report online April 12 in Science Advances....

https://www.sciencenews.org/article/new-gra...st-temperatures



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"Every long-term security is nothing more than a claim on some expected future stream of cash that will be delivered into the hands of investors over time. For a given stream of expected future cash payments, the higher the price investors pay today for that stream of cash, the lower the long-term return they will achieve on their investment over time." - Dr John Hussman

"If I had even the slightest grasp upon my own faculties, I would not make essays, I would make decisions." ― Michel de Montaigne

Said 'Thanks' for this post: mullokintyre  lgrif  
 
nipper
post Posted: Mar 26 2019, 04:47 PM
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Now, here's a twist
https://www-gizmodo-com-au.cdn.ampproject.o...-of-the-year%2F

QUOTE
Last year, a team of physicists led by graduate student Yuan Cao made a discovery as close to shocking as science can get. They stacked a pair of graphene sheets on top of one another, cooled the system down to near absolute zero, and twisted one of the sheets to a 1.1-degree angle relative to the other.

They added a voltage, and the system became a kind of insulator such that the interactions between the particles themselves prevent electrons from moving. When they added more electrons, the system became a superconductor, a kind of system in which electrical charge can move without resistance.

But...
QUOTE
Excitement for bilayer graphene stems from the physics that underlies it, not the promise that it will become useful in tech like quantum computers or solar panels. But the field likely won’t die soon.




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"Every long-term security is nothing more than a claim on some expected future stream of cash that will be delivered into the hands of investors over time. For a given stream of expected future cash payments, the higher the price investors pay today for that stream of cash, the lower the long-term return they will achieve on their investment over time." - Dr John Hussman

"If I had even the slightest grasp upon my own faculties, I would not make essays, I would make decisions." ― Michel de Montaigne
 
nipper
post Posted: Mar 16 2019, 02:36 PM
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In Reply To: mullokintyre's post @ Mar 16 2019, 12:48 PM

QUOTE
...graphene .. may also exhibit properties of second sound at even higher temperatures approaching or exceeding room temperature...
- that's something to aim for. Recharging batteries, for one.



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"Every long-term security is nothing more than a claim on some expected future stream of cash that will be delivered into the hands of investors over time. For a given stream of expected future cash payments, the higher the price investors pay today for that stream of cash, the lower the long-term return they will achieve on their investment over time." - Dr John Hussman

"If I had even the slightest grasp upon my own faculties, I would not make essays, I would make decisions." ― Michel de Montaigne
 
mullokintyre
post Posted: Mar 16 2019, 12:48 PM
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The wonders of Graphene.


QUOTE
But now MIT researchers have observed this seemingly implausible mode of heat transport, known as “second sound,” in a rather commonplace material: graphite — the stuff of pencil lead.

At temperatures of 120 kelvin, or -240 degrees Fahrenheit, they saw clear signs that heat can travel through graphite in a wavelike motion. Points that were originally warm are left instantly cold, as the heat moves across the material at close to the speed of sound. The behavior resembles the wavelike way in which sound travels through air, so scientists have dubbed this exotic mode of heat transport “second sound.”

The new results represent the highest temperature at which scientists have observed second sound. What’s more, graphite is a commercially available material, in contrast to more pure, hard-to-control materials that have exhibited second sound at 20 K, (-420 F) — temperatures that would be far too cold to run any practical applications.

The discovery, published in Science, suggests that graphite, and perhaps its high-performance relative, graphene, may efficiently remove heat in microelectronic devices in a way that was previously unrecognized.

“There’s a huge push to make things smaller and denser for devices like our computers and electronics, and thermal management becomes more difficult at these scales,” says Keith Nelson, the Haslam and Dewey Professor of Chemistry at MIT. “There’s good reason to believe that second sound might be more pronounced in graphene, even at room temperature. If it turns out graphene can efficiently remove heat as waves, that would certainly be wonderful.”Normally, heat travels through crystals in a diffusive manner, carried by “phonons,” or packets of acoustic vibrational energy. The microscopic structure of any crystalline solid is a lattice of atoms that vibrate as heat moves through the material. These lattice vibrations, the phonons, ultimately carry heat away, diffusing it from its source, though that source remains the warmest region, much like a kettle gradually cooling on a stove.

The kettle remains the warmest spot because as heat is carried away by molecules in the air, these molecules are constantly scattered in every direction, including back toward the kettle. This “back-scattering” occurs for phonons as well, keeping the original heated region of a solid the warmest spot even as heat diffuses away.

However, in materials that exhibit second sound, this back-scattering is heavily suppressed. Phonons instead conserve momentum and hurtle away en masse, and the heat stored in the phonons is carried as a wave. Thus, the point that was originally heated is almost instantly cooled, at close to the speed of sound.

Previous theoretical work in Chen’s group had suggested that, within a range of temperatures, phonons in graphene may interact predominately in a momentum-conserving fashion, indicating that graphene may exhibit second sound. Last year, Huberman, a member of Chen’s lab, was curious whether this might be true for more commonplace materials like graphite.

Building upon tools previously developed in Chen’s group for graphene, he developed an intricate model to numerically simulate the transport of phonons in a sample of graphite. For each phonon, he kept track of every possible scattering event that could take place with every other phonon, based upon their direction and energy. He ran the simulations over a range of temperatures, from 50 K to room temperature, and found that heat might flow in a manner similar to second sound at temperatures between 80 and 120 K.

Huberman had been collaborating with Duncan, in Nelson’s group, on another project. When he shared his predictions with Duncan, the experimentalist decided to put Huberman’s calculations to the test.

“This was an amazing collaboration,” Chen says. “Ryan basically dropped everything to do this experiment, in a very short time.”

“We were really in the express lane with this,” Duncan adds.

Upending the norm

Duncan’s experiment centered around a small, 10-square-millimeter sample of commercially available graphite.

Using a technique called transient thermal grating, he crossed two laser beams so that the interference of their light generated a “ripple” pattern on the surface of a small sample of graphite. The regions of the sample underlying the ripple’s crests were heated, while those that corresponded to the ripple’s troughs remained unheated. The distance between crests was about 10 microns.

Duncan then shone onto the sample a third laser beam, whose light was diffracted by the ripple, and its signal was measured by a photodetector. This signal was proportional to the height of the ripple pattern, which depended on how much hotter the crests were than the troughs. In this way, Duncan could track how heat flowed across the sample over time.

If heat were to flow normally in the sample, Duncan would have seen the surface ripples slowly diminish as heat moved from crests to troughs, washing the ripple pattern away. Instead, he observed “a totally different behavior” at 120 K.

Rather than seeing the crests gradually decay to the same level as the troughs as they cooled, the crests actually became cooler than the troughs, so that the ripple pattern was inverted — meaning that for some of the time, heat actually flowed from cooler regions into warmer regions.

“That’s completely contrary to our everyday experience, and to thermal transport in almost every material at any temperature,” Duncan says. “This really looked like second sound. When I saw this I had to sit down for five minutes, and I said to myself, ‘This cannot be real.’ But I ran the experiment overnight to see if it happened again, and it proved to be very reproducible.”

According to Huberman’s predictions, graphite’s two-dimensional relative, graphene, may also exhibit properties of second sound at even higher temperatures approaching or exceeding room temperature. If this is the case, which they plan to test, then graphene may be a practical option for cooling ever-denser microelectronic devices.

“This is one of a small number of career highlights that I would look to, where results really upend the way you normally think about something,” Nelson says. “It’s made more exciting by the fact that, depending on where it goes from here, there could be interesting applications in the future. There’s no question from a fundamental point of view, it’s really unusual and exciting.”

ya gotta love science, as distinct from modelling.

Mick



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sent from my Olivetti Typewriter.

Said 'Thanks' for this post: nipper  lgrif  
 
nipper
post Posted: Nov 17 2018, 02:33 PM
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In Reply To: blacksheep's post @ Nov 17 2018, 01:55 PM

QUOTE
the lack of standards for graphene production gives rise to bad quality of the material sold in the open market. This has been stalling the development of the future applications...
- I could imagine this is a real problem. Inconsistency, too.



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"Every long-term security is nothing more than a claim on some expected future stream of cash that will be delivered into the hands of investors over time. For a given stream of expected future cash payments, the higher the price investors pay today for that stream of cash, the lower the long-term return they will achieve on their investment over time." - Dr John Hussman

"If I had even the slightest grasp upon my own faculties, I would not make essays, I would make decisions." ― Michel de Montaigne
 

sentifi.com

Share Cafe Sentifi Top themes and market attention on:


blacksheep
post Posted: Nov 17 2018, 01:55 PM
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The worth of sorting graphene flakes from fakes
15 Nov 2018 Anna Demming
extract
QUOTE
Suffering from a few too many
The miraculous properties of graphene have attracted headlines ever since the material was isolated and characterized by Kostya Novoselov and Andre Geim, who were awarded a Nobel Prize for the work in 2010. Strictly speaking graphene is a single layer of carbon atoms arranged in a honeycomb like lattice, but “few-layer” graphene can retain much of the fascinating alliance of extraordinary electrical and mechanical properties. However when the number of layers starts to number more than just a few, the wonder material behaves less and less like graphene and more and more like graphite, also known as pencil lead.

The importance of distinguishing graphene from graphite has been recognized for several years, prompting the International Standardization Organization to set a precise definition for what can be defined as graphene – fewer than 10 layers. While this clarifies things for patent attorneys, a definition is little use to the graphene sector if suppliers continue to supply graphite in place of graphene, and users lack the resources to distinguish graphene flakes from graphene fakes.

“Whether producers of the counterfeit graphene are aware of the poor quality is unclear,” says Neto. “Regardless, the lack of standards for graphene production gives rise to bad quality of the material sold in the open market. This has been stalling the development of the future applications.”

The results of the NUS study come just months after the establishment of the Graphene Service in the UK, a collaboration between the National Physical Laboratory in Teddington and the National Graphene Institute at the University of Manchester. The Graphene Service aims to leverage the expertise in the two institutions to characterize samples for users and provide advice on their potential uses.

https://physicsworld.com/a/the-value-of-sor...kes-from-fakes/



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The herd instinct among forecasters makes sheep look like independent thinkers. Edgar Fiedler

If the freedom of speech is taken away then dumb and silent we may be led, like sheep to the slaughter. George Washington
 
blacksheep
post Posted: Oct 15 2018, 11:56 AM
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The Graphene Promise - Disruptor or Disrupted
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By Bob Kohut | 15.10.2018

What’s the “next big thing” to hit the market? This question has tantalized rabid investors in search of the big payoff since forever.

Next big thing candidates typically are involved in business operations that have the potential to make a significant impact on the way things get done in the world. Many are technology firms. As far back as 2012 an article appearing on the website of Canadian metals dealer Kitco heralded graphite as the “new black gold.” Active investors at that time know Kitco was not alone in touting graphite, in large part for its application potential in yet another big thing, the coming boom in Electric Vehicles (EVs).

Many investors focused on the robust demand projections for graphite. The following graph presents more recent data.

Yet that optimistic picture has not saved the fortunes of Australia’s largest graphite producer, Syrah Resources (SYR) from a volatile share price and third place on the ASX Top Thirty Short List.

As is typical of suddenly “hot” commodities like graphite, producers rush in to capitalise on rising demand, only to see commodity prices drop due to oversupply concerns. Demand is only half of the equation with which investors need to be concerned.


3 ASX listed stocks focused on graphene get a mention - TLG, FGR and AXE
QUOTE
Buried in the graphite hype back then was a material made from graphite, hailed at the time as having applications so revolutionary the disruptive effect was compared to the advent of electricity—graphene. This “wonder” material also earned the accolade of “new black gold”.

For many investors, what the business world could do with graphene was more important than its composition or how it is made. And the list of applications read like something out of science fiction.


read more - http://www.thebull.com.au/premium/a/77664-...-disrupted.html



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The herd instinct among forecasters makes sheep look like independent thinkers. Edgar Fiedler

If the freedom of speech is taken away then dumb and silent we may be led, like sheep to the slaughter. George Washington
 
blacksheep
post Posted: Jun 20 2018, 11:02 PM
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The world's first-ever graphene sports shoes
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(Nanowerk News) The world’s first-ever sports shoes to utilise graphene – the strongest material on the planet – have been unveiled by The University of Manchester and British brand inov-8.

Collaborating with graphene experts at National Graphene Institute, the brand has been able to develop a graphene-enhanced rubber. They have developed rubber outsoles for running and fitness shoes that in testing have outlasted 1,000 miles and are scientifically proven to be 50% harder wearing.


https://www.nanowerk.com/nanotechnology-new...ewsid=50476.php
Attached image(s)
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--------------------
The herd instinct among forecasters makes sheep look like independent thinkers. Edgar Fiedler

If the freedom of speech is taken away then dumb and silent we may be led, like sheep to the slaughter. George Washington
 
blacksheep
post Posted: Jun 16 2018, 02:34 PM
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Interesting video - http://imgne.com/

QUOTE
Imagine all the graphene
IMAGINE Intelligent Materials has developed an electrically conductive geotextile from graphene that can detect holes in coal seam gas waste storage ponds and tanks during construction.


featured in Mining Monthly - http://www.miningmonthly.com/innovation/ne...ll-the-graphene



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The herd instinct among forecasters makes sheep look like independent thinkers. Edgar Fiedler

If the freedom of speech is taken away then dumb and silent we may be led, like sheep to the slaughter. George Washington
 
 


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