Energy Conversion: Speeding Up Material Discovery

Energy conversion: Speeding up material discovery

Algorithm take months, not years, to find material for improved energy conversion

In even the most fuel-efficient cars, about 60 percent of the total energy of gasoline is lost through heat in the exhaust pipe and radiator. To combat this, researchers are developing new thermoelectic materials that can convert heat into electricity. These semiconducting materials could recirculate electricity back into the vehicle and improve fuel efficiency by up to 5 percent.

The challenge is, current thermoelectric materials for waste heat recovery are very expensive and time consuming to develop. One of the state of the art materials, made from a combination of hafnium and zirconium (elements most commonly used in nuclear reactors), took 15 years from its initial discovery to optimized performance.

Now, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed an algorithm that can discover and optimize these materials in a matter of months, relying on solving quantum mechanical equations, without any experimental input.

“These thermoelectric systems are very complicated,” said Boris Kozinsky, a recently appointed Associate Professor of Computational Materials Science at SEAS and senior author of the paper. “Semiconducting materials need to have very specific properties to work in this system, including high electrical conductivity, high thermopower, and low thermal conductivity, so that all that heat gets converted into electricity. Our goal was to find a new material that satisfies all the important properties for thermoelectric conversion while at the same time being stable and cheap.”

UK Chancellor: I must cut tax benefits for working poor to help them

George Osborne, born to a titled millionaire, has explained that he is cutting the tax-credits that let the working poor survive, despite the Tory party’s election promise not to do any such thing – because it will reduce the deficit and therefore save them from the cuts that the country would have to pay in the future in order to pay down those debts.

Osborne did not moot the possibility of taxing the country’s billionaires, including the “non-doms” who get to pretend that they live in an offshore tax-haven and duck their taxes. He also neglected to mention that countries are not companies, and that having a national bank and your own mint means that national debts are completely unlike the debts taken on by firms or households.

Osborne also didn’t mention the possibility of taxing the companies that pretend that their profits are made in tax-havens and that all their UK income must be remitted to an offshore firm in nonsensical trademark licenses.

Finally, Osborne didn’t mention the situation in which people working full-time jobs (or piecing together a full-time living from zero-hours contracts) can’t afford to pay for rent and food for their families and require benefits to remain solvent enough to show up for work each day, meaning that the firms paying the sub-survival wages are getting a massive tax subsidy in the form of a fed and housed workforce that comes at tax-payers’ expense.

Instead, Osborne explained that he would make the poorest workers in the UK even poorer, for their own benefit.

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dotmpotter

9 years ago

A Merry-Go-Round That Turns The Power Of Play Into Electricity - Vlad Vilenski posted in Green, Electricity and Non Profit

Empower Playgrounds is a nonprofit that has come up with an intriguing solution: Harnessing the power of play, it provides merry-go-rounds to schools in Ghana that generate and store electricity as they are spun around, even while teeming with laughing and smiling kids.

Continue to fastcodesign.com

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dotmpotter

9 years ago

Amazing Maps of the World

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dotmpotter

9 years ago

Ifixit repair kits: everything you need to fix everything

Ifixit produce open repair guides for everything imaginable, in a variety of languages, and help sustain a global community of independent repairers who divert electronics from e-waste dumps and keep poor and marginalized people connected to their work, school and families.

The Ifixit repair kits are thoughtful, high-specification, low-cost toolkits designed to work on all modern gadgets, as well as traditional ones (for example, Ifixit manufacture their own drivers for Apple’s bizarre “pentalobe” screws, which Apple had instructed its Genius Bar staff to quietly swap in during routine repairs).

The big daddy of Ifixit kits is the $130 128-bit Universal Bit Kit, which comes in a handsome wooden case and is covered by Ifixit’s lifetime warranty.

But Ifixit makes smaller, more specialized kits, including theSmartphone Repair Kit, priced at $25, specifically aimed at the budgets of enterprising high-school students who want to start their own smartphone repair businesses, using Ifixit’s manuals.

http://boingboing.net/2015/12/02/ifixit-repair-kits-everything.html

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dotmpotter

9 years ago

Can an army of voluntary "mappers" (like you) help end child slavery on Lake Volta, Ghana?

LEARN MORE about being a “mapper” here.

Consider a 100% tax-deductible DONATION to free a child from slavery on Lake Volta here: madeinafreeworld.com/ghana

Silica nanoparticles could be used to repair damaged teeth

Researchers at the University of Birmingham have shown how the development of coated silica nanoparticles could be used in restorative treatment of sensitive teeth and preventing the onset of tooth decay.

The study, published in the Journal of Dentistry, shows how sub-micron silica particles can be prepared to deliver important compounds into damaged teeth through tubules in the dentine.

The tiny particles can be bound to compounds ranging from calcium tooth building materials to antimicrobials that prevent infection.

Professor Damien Walmsley, from the School of Dentistry at the University of Birmingham, explained, “The dentine of our teeth have numerous microscopic holes, which are the entrances to tubules that run through to the nerve. When your outer enamel is breached, the exposure of these tubules is really noticeable. If you drink something cold, you can feel the sensitivity in your teeth because these tubules run directly through to the nerve and the soft tissue of the tooth.”

“Our plan was to use target those same tubules with a multifunctional agent that can help repair and restore the tooth, while protecting it against further infection that could penetrate the pulp and cause irreversible damage.”

The aim of restorative agents is to increase the mineral content of both the enamel and dentine, with the particles acting like seeds for further growth that would close the tubules.

Previous attempts have used compounds of calcium fluoride, combinations of carbonate-hydroxypatite nanocrystals and bioactive glass, but all have seen limited success as they are liable to aggregate on delivery to the tubules. This prevents them from being able to enter the opening which is only 1 to 4 microns in width.

However, the Birmingham team turned to sub-micron silica particles that had been prepared with a surface coating to reduce the chance of aggregation.

When observed using high definition SEM (Scanning Electron Microsopy), the researchers saw promising signs that suggested that the aggregation obstacle had been overcome.

Professor Zoe Pikramenou, from the School of Chemistry at the University of Birmingham, said, “These silica particles are available in a range of sizes, from nanometre to sub-micron, without altering their porous nature. It is this that makes them an ideal container for calcium based compounds to restore the teeth, and antibacterial compounds to protect them. All we needed to do was find the right way of coating them to get them to their target. We have found that different coatings does change the way that they interact with the tooth surface.”

“We tested a number of different options to see which would allow for the highest level particle penetration into the tubules, and identified a hydrophobic surface coating that provides real hope for the development of an effective agent.”

Our next steps are to optimise the coatings and then see how effective the particles are blocking the communication with the inside of the tooth. The ultimate aim is to provide relief from the pain of sensitivity.

University of Birmingham

Nanotechnology World Association