Tag Archives: electricity

Environmentally sustainable electromobility

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Researchers at the Norwegian University of Science and Technology pose an interesting question in a Dec. 8, 2016 news item on Nanowerk,

Does it really help to drive an electric car if the electricity you use to charge the batteries come from a coal mine in Germany, or if the batteries were manufactured in China using coal?

Researchers at the Norwegian University of Science and Technology’s Industrial Ecology Programme have looked at all of the environmental costs of electric vehicles to determine the cradle-to-grave environmental footprint of building and operating these vehicles.

Increasingly, researchers are examining not just immediate environmental impacts but the impact a product has throughout its life cycle as this Dec. 8, 2016 Norwegian University of Science and Technology press release on EurekAlert notes,

In the 6 December [2016] issue of Nature Nanotechnology, the researchers report on a model that can help guide developers as they consider new nanomaterials for batteries or fuel cells. The goal is to create the most environmentally sustainable vehicle fleet possible, which is no small challenge given that there are already an estimated 1 billion cars and light trucks on the world’s roads, a number that is expected to double by 2035.

With this in mind, the researchers created an environmental life-cycle screening framework that looked at the environmental and other impacts of extraction, refining, synthesis, performance, durability and recyclablility of materials.

This allowed the researchers to evaluate the most promising nanomaterials for lithium-ion batteries (LIB) and proton exchange membrane hydrogen fuel cells (PEMFC) as power sources for electric vehicles. “Our analysis of the current situation clearly outlines the challenge,” the researchers wrote. “The materials with the best potential environmental profiles during the material extraction and production phase…. often present environmental disadvantages during their use phase… and vice versa.”

The hope is that by identifying all the environmental costs of different materials used to build electric cars, designers and engineers can “make the right design trade-offs that optimize LIB and PEMFC nanomaterials for EV usage towards mitigating climate change,” the authors wrote.

They encouraged material scientists and those who conduct life-cycle assessments to work together so that electric cars can be a key contributor to mitigating the effects of transportation on climate change.

Here’s a link to and a citation for the paper,

Nanotechnology for environmentally sustainable electromobility by Linda Ager-Wick Ellingsen, Christine Roxanne Hung, Guillaume Majeau-Bettez, Bhawna Singh, Zhongwei Chen, M. Stanley Whittingham, & Anders Hammer Strømman. Nature Nanotechnology 11, 1039–1051 (2016)  doi:10.1038/nnano.2016.237 Published online 06 December 2016 Corrected online 14 December 2016

This paper is behind a paywall.

Monster science (a book announcement and interview)

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Helaine Becker has launched a new children’s science book incorporating monsters with science. The title, unsurprisingly, is: ‘Monster Science’. Here’s more about the book from Helaine’s Oct. 14, 2016 post on Sci/Why where she shares two reviews,

“From Frankenstein’s creation to Nessie, Becker uses the creatures of our scariest stories as a springboard for an introduction to the scientific understandings that might make such creatures possible—or impossible. In addition to man-made monsters and legendary sea creatures, she covers vampires, zombies, werewolves, and wild, humanlike creatures like Bigfoot. Chapter by chapter, she provides references from literature, film, and popular culture, including a bit of science, a bit of history, and a plentiful helping of humor. She includes numerous monster facts, suggests weapons of defense, and concludes each section with a test-yourself quiz. Science topics covered range widely: electricity, genetic engineering, “demonic diseases,” the nature of our blood and the circulatory system, the possibility of immortality, animal classification, evolution, cannibalism, optical illusions, heredity, hoaxes, and the very real profession of cryptozoology, or the search for hitherto unidentified creatures. … Kirkus

Then, there’s this one,

“A highlight of this work is its exploration of the often symbiotic relationship between culture and science; figures such as Shelley, John Polidori (The Vampyre), and filmmaker George Romero (Night of the Living Dead) merged cultural fascination with scientific development to create truly inspiring works and further public interest in science… School Library Journal

Interview with Helaine Becker

Not to be confused with ‘Interview with a vampire’, this one is not novel-length and includes a scoop about an upcoming book in 2017,

Were you surprised by anything when you were researching and/or witting the book?

I learned so much while writing Monster Science – it’s one of the reasons I enjoy writing nonfiction, especially for kids. I always turn up fascinating stuff. I was surprised to learn that werewolves were rounded up and burned at the stake, just like witches, during the period of the Inquisition. Werewolves, it turns out, were thought to be witches – usually male ones – who could shape shift.

My fave fact of all is that vampires would still have to eat their vegetables.

Did you have to leave any monsters/pop culture references/science out of the book? And, why?

Children’s books have very tight space constraints, but my research is comprehensive and complete. That means we have to pick and choose what stays in. It’s gotta be the very best! I work closely with my editors on this, and sometimes we have, shall we say, “heated” discussions.” For Monster Science, I was particularly sorry to see the fascinating back story of the mad scientist trope end up with a stake in its heart.

Did you have a favourite monster before you started? If so, has your favourite changed? Or if you didn’t have one before writing the book, have you since developed a favourite monster?

I’ve had an uneasy relationship with vampires from the age of about 7, after watching an episode of Gilligan’s Island. It featured a “humorous” dream sequence with Gilligan as the vampire. I failed to see the humor at that tender age, and was terrified out of my socks. And anyone remember the original Dark Shadows? Barnabus Collins? Yeah. That show should have never been on in the afternoon. I slept with the blankies up to my ears until my mid-thirties. (Who am I kidding? I still do!)

Are you hoping to tie this book into the Frankenstein bicentennial celebrations?

Illustrated children’s books have very long time lines from concept to finished book. I wrote Monster Science several years ago, before I had any notion of Frankenstein bicentennials. But now that we’ve arrived at this auspicious date, I’m excited! I’d love to participate in some way. I will put on my zzz zzzz zzzt thinking cap.

Where can your fans come to a reading or some other event?

I do dozens of school visits and festival events every year. Some of them might be focused on a specific book, like Monster Science, but most usually feature discussions around several of my titles. This holiday season, for example, I will be doing events around my latest picture book, a very Canadian Christmas-themed title called Deck the Halls. It’s the third in a very popular series. Anyone can drop in to the Sherway Gardens branch of Indigo Book Store [in Toronto] at noon on Sunday, Dec. 4 [2016], to take part in that.

I’ll be doing many events in association with the Forest of Reading, one of North America’s largest children’s choice award programs this spring. More than 250,000 children participate! I am honored to have two science-related books nominated this year, Worms for Breakfast: How to Feed a Zoo (Owlkids) and Everything: Space (National Geographic Kids). I will also be the keynote at the Killaloe Literary Festival in beautiful northern Ontario at the end of May. Best place to look for my latest book and schedule info is my blog, http://helainebecker.blogspot.ca/.

Is there anything you’d like to add?

For insiders only: Coming soon! Look for my upcoming picture book biography of William Playfair, the Victorian era scoundrel who single-handedly invented the field of infographics. It’s called Lines, Bars and Circles and will be published by Kids Can Press early in 2017.

Thank you, Helaine! (I usually don’t get funny interviews. It makes for a good change of pace.)

Getting back to ‘Monster Science’, you can purchase the book here.

Vitamin-driven lithium-ion battery from the University of Toronto

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It seems vitamins aren’t just good for health, they’re also good for batteries. My Aug. 2, 2016 post on vitamins and batteries focused on work from Harvard, this time the work is from the University of Toronto (Canada). From an Aug. 3, 2016 news item on ScienceDaily,

A team of University of Toronto chemists has created a battery that stores energy in a biologically derived unit, paving the way for cheaper consumer electronics that are easier on the environment.

The battery is similar to many commercially-available high-energy lithium-ion batteries with one important difference. It uses flavin from vitamin B2 as the cathode: the part that stores the electricity that is released when connected to a device.

“We’ve been looking to nature for a while to find complex molecules for use in a number of consumer electronics applications,” says Dwight Seferos, an associate professor in U of T’s Department of Chemistry and Canada Research Chair in Polymer Nanotechnology.

“When you take something made by nature that is already complex, you end up spending less time making new material,” says Seferos.

An Aug. 2, 2016 University of Toronto news release (also on EurekAlert) by Peter McMahon, which originated the news item, explains further,

To understand the discovery, it’s important to know that modern batteries contain three basic parts:

  • a positive terminal – the metal part that touches devices to power them – connected to a cathode inside the battery casing
  • a negative terminal connected to an anode inside the battery casing
  • an electrolyte solution, in which ions can travel between the cathode and anode electrodes

When a battery is connected to a phone, iPod, camera or other device that requires power, electrons flow from the anode – the negatively charged electrode of the device supplying current – out to the device, then into the cathode and ions migrate through the electrolyte solution to balance the charge. When connected to a charger, this process happens in reverse.

The reaction in the anode creates electrons and the reaction in the cathode absorbs them when discharging. The net product is electricity. The battery will continue to produce electricity until one or both of the electrodes run out of the substance necessary for the reactions to occur.

Organic chemistry is kind of like Lego

While bio-derived battery parts have been created previously, this is the first one that uses bio-derived polymers – long-chain molecules – for one of the electrodes, essentially allowing battery energy to be stored in a vitamin-created plastic, instead of costlier, harder to process, and more environmentally-harmful metals such as cobalt.

“Getting the right material evolved over time and definitely took some test reactions,” says paper co-author and doctoral student Tyler Schon. “In a lot of ways, it looked like this could have failed. It definitely took a lot of perseverance.”

Schon, Seferos and colleagues happened upon the material while testing a variety of long-chain polymers – specifically pendant group polymers: the molecules attached to a ‘backbone’ chain of a long molecule.

“Organic chemistry is kind of like Lego,” he says. “You put things together in a certain order, but some things that look like they’ll fit together on paper don’t in reality. We tried a few approaches and the fifth one worked,” says Seferos.

Building a better power pack

The team created the material from vitamin B2 that originates in genetically-modified fungi using a semi-synthetic process to prepare the polymer by linking two flavin units to a long-chain molecule backbone.

This allows for a green battery with high capacity and high voltage – something increasingly important as the ‘Internet of Things’ continues to link us together more and more through our battery-powered portable devices.

“It’s a pretty safe, natural compound,” Seferos adds. “If you wanted to, you could actually eat the source material it comes from.”

B2’s ability to be reduced and oxidized makes its well-suited for a lithium ion battery.

“B2 can accept up to two electrons at a time,” says Seferos. “This makes it easy to take multiple charges and have a high capacity compared to a lot of other available molecules.”

A step to greener electronics

“It’s been a lot of trial-and-error,” says Schon. “Now we’re looking to design new variants that can be recharged again and again.”

While the current prototype is on the scale of a hearing aid battery, the team hopes their breakthrough could lay the groundwork for powerful, thin, flexible, and even transparent metal-free batteries that could support the next wave of consumer electronics.

Here’s a link to and a citation for the paper,

Bio-Derived Polymers for Sustainable Lithium-Ion Batteries by Tyler B. Schon, Andrew J. Tilley, Colin R. Bridges, Mark B. Miltenburg, and Dwight S. Seferos. Advanced Functional Materials DOI: 10.1002/adfm.201602114 Version of Record online: 14 JUL 2016

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

Osmotic power: electricity generated with water, salt and a 3-atoms-thick membrane

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EPFL researchers have developed a system that generates electricity from osmosis with unparalleled efficiency. Their work, featured in “Nature”, uses seawater, fresh water, and a new type of membrane just three atoms thick.

A July 13, 2016 news item on Nanowerk highlights  research on osmotic power at École polytechnique fédérale de Lausanne (EPFL; Switzerland),

Proponents of clean energy will soon have a new source to add to their existing array of solar, wind, and hydropower: osmotic power. Or more specifically, energy generated by a natural phenomenon occurring when fresh water comes into contact with seawater through a membrane.

Researchers at EPFL’s Laboratory of Nanoscale Biology have developed an osmotic power generation system that delivers never-before-seen yields. Their innovation lies in a three atoms thick membrane used to separate the two fluids. …

A July 14, 2016 EPFL press release (also on EurekAlert but published July 13, 2016), which originated the news item, describes the research,

The concept is fairly simple. A semipermeable membrane separates two fluids with different salt concentrations. Salt ions travel through the membrane until the salt concentrations in the two fluids reach equilibrium. That phenomenon is precisely osmosis.

If the system is used with seawater and fresh water, salt ions in the seawater pass through the membrane into the fresh water until both fluids have the same salt concentration. And since an ion is simply an atom with an electrical charge, the movement of the salt ions can be harnessed to generate electricity.

A 3 atoms thick, selective membrane that does the job

EPFL’s system consists of two liquid-filled compartments separated by a thin membrane made of molybdenum disulfide. The membrane has a tiny hole, or nanopore, through which seawater ions pass into the fresh water until the two fluids’ salt concentrations are equal. As the ions pass through the nanopore, their electrons are transferred to an electrode – which is what is used to generate an electric current.

Thanks to its properties the membrane allows positively-charged ions to pass through, while pushing away most of the negatively-charged ones. That creates voltage between the two liquids as one builds up a positive charge and the other a negative charge. This voltage is what causes the current generated by the transfer of ions to flow.

“We had to first fabricate and then investigate the optimal size of the nanopore. If it’s too big, negative ions can pass through and the resulting voltage would be too low. If it’s too small, not enough ions can pass through and the current would be too weak,” said Jiandong Feng, lead author of the research.

What sets EPFL’s system apart is its membrane. In these types of systems, the current increases with a thinner membrane. And EPFL’s membrane is just a few atoms thick. The material it is made of – molybdenum disulfide – is ideal for generating an osmotic current. “This is the first time a two-dimensional material has been used for this type of application,” said Aleksandra Radenovic, head of the laboratory of Nanoscale Biology

Powering 50’000 energy-saving light bulbs with 1m2 membrane

The potential of the new system is huge. According to their calculations, a 1m2 membrane with 30% of its surface covered by nanopores should be able to produce 1MW of electricity – or enough to power 50,000 standard energy-saving light bulbs. And since molybdenum disulfide (MoS2) is easily found in nature or can be grown by chemical vapor deposition, the system could feasibly be ramped up for large-scale power generation. The major challenge in scaling-up this process is finding out how to make relatively uniform pores.

Until now, researchers have worked on a membrane with a single nanopore, in order to understand precisely what was going on. ” From an engineering perspective, single nanopore system is ideal to further our fundamental understanding of 8=-based processes and provide useful information for industry-level commercialization”, said Jiandong Feng.

The researchers were able to run a nanotransistor from the current generated by a single nanopore and thus demonstrated a self-powered nanosystem. Low-power single-layer MoS2 transistors were fabricated in collaboration with Andras Kis’ team at at EPFL, while molecular dynamics simulations were performed by collaborators at University of Illinois at Urbana–Champaign

Harnessing the potential of estuaries

EPFL’s research is part of a growing trend. For the past several years, scientists around the world have been developing systems that leverage osmotic power to create electricity. Pilot projects have sprung up in places such as Norway, the Netherlands, Japan, and the United States to generate energy at estuaries, where rivers flow into the sea. For now, the membranes used in most systems are organic and fragile, and deliver low yields. Some systems use the movement of water, rather than ions, to power turbines that in turn produce electricity.

Once the systems become more robust, osmotic power could play a major role in the generation of renewable energy. While solar panels require adequate sunlight and wind turbines adequate wind, osmotic energy can be produced just about any time of day or night – provided there’s an estuary nearby.

Here’s a link to and a citation for the paper,

Single-layer MoS2 nanopores as nanopower generators by Jiandong Feng, Michael Graf, Ke Liu, Dmitry Ovchinnikov, Dumitru Dumcenco, Mohammad Heiranian, Vishal Nandigana, Narayana R. Aluru, Andras Kis, & Aleksandra Radenovic. Nature (2016)  doi:10.1038/nature18593 Published online 13 July 2016

This paper is behind a paywall.

A de-icer and a preventative for airplane wings from Rice University

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I last mentioned this graphene-based work (from James Tour at Rice University in Texas, US) on de-icing not just airplane wings but also windshields, skyscrapers and more in a Sept. 17, 2014 posting. The latest study indicates the technology could be used as a preventative according to a May 23, 2016 news item on phys.org,

Rice University scientists have advanced their graphene-based de-icer to serve a dual purpose. The new material still melts ice from wings and wires when conditions get too cold. But if the air is above 7 degrees Fahrenheit, ice won’t form at all.

A May 23, 2016 Rice University news release (also on EurekAlert), which originated the news item, goes on to describe the work in more detail,

The Rice lab of chemist James Tour gave its de-icer superhydrophobic (water-repelling) capabilities that passively prevent water from freezing above 7 degrees. The tough film that forms when the de-icer is sprayed on a surface is made of atom-thin graphene nanoribbons that are conductive, so the material can also be heated with electricity to melt ice and snow in colder conditions.

The material can be spray-coated, making it suitable for large applications like aircraft, power lines, radar domes and ships, according to the researchers. …

“We’ve learned to make an ice-resistant material for milder conditions in which heating isn’t even necessary, but having the option is useful,” Tour said. “What we now have is a very thin, robust coating that can keep large areas free of ice and snow in a wide range of conditions.”

Tour, lead authors Tuo Wang, a Rice graduate student, and Yonghao Zheng, a Rice postdoctoral researcher, and their colleagues tested the film on glass and plastic.

Materials are superhydrophobic if they have a water-contact angle larger than 150 degrees. The term refers to the angle at which the surface of the water meets the surface of the material. The greater the beading, the higher the angle. An angle of 0 degrees is basically a puddle, while a maximum angle of 180 degrees defines a sphere just touching the surface.

The Rice films use graphene nanoribbons modified with a fluorine compound to enhance their hydrophobicity. They found that nanoribbons modified with longer perfluorinated chains resulted in films with a higher contact angle, suggesting that the films are tunable for particular conditions, Tour said.

Warming test surfaces to room temperature and cooling again had no effect on the film’s properties, he said.

The researchers discovered that below 7 degrees, water would condense within the structure’s pores, causing the surface to lose both its superhydrophobic and ice-phobic properties. At that point, applying at least 12 volts of electricity warmed them enough to retain its repellant properties.

Applying 40 volts to the film brought it to room temperature, even if the ambient temperature was 25 degrees below zero. Ice allowed to form at that temperature melted after 90 seconds of resistive heating.

The researchers found that while effective, the de-icing mode did not remove water completely, as some remained trapped in the pores between linked nanoribbon bundles. Adding a lubricant with a low melting point (minus 61 degrees F) to the film made the surface slippery, sped de-icing and saved energy.

Here’s a link to and a citation for the paper,

Passive Anti-icing and Active Deicing Films by Tuo Wang, Yonghao Zheng, Abdul-Rahman O. Raji, Yilun Li, William K.A. Sikkema, and James M. Tour. ACS Appl. Mater. Interfaces, Just Accepted Manuscript DOI: 10.1021/acsami.6b03060 Publication Date (Web): May 18, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

Constructing an autonomous Maxwell’s demon as a self-contained information-powered refrigerator

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Aalto University (Finland) was the lead research institution for  INFERNOS, a European Union-funded project concerning Maxwell’s demon. Here’s an excerpt from an Oct. 14, 2013 post featuring the project,

An Oct. 9, 2013 news item on Nanowerk ties together INFERNOS and the ‘demon’,

Maxwell’s Demon is an imaginary creature that the mathematician James Clerk Maxwell created in 1897. The creature could turn heat into work without causing any other change, which violates the second law of thermodynamics. The primary goal of the European project INFERNOS (Information, fluctuations, and energy control in small systems) is to realize experimentally Maxwell’s Demon; in other words, to develop the electronic and biomolecular nanodevices that support this principle.

…

I like the INFERNOS logo, demon and all,

Logo of the European project INFERNOS (Information, fluctuations, and energy control in small systems).

A Jan. 11, 2016 news item on Nanowerk seems to be highlighting a paper resulting from the INFERNOS project (Note: A link has been removed),

On [a] theoretical level, the thought experiment has been an object of consideration for nearly 150 years, but testing it experimentally has been impossible until the last few years. Making use of nanotechnology, scientists from Aalto University have now succeeded in constructing an autonomous Maxwell’s demon that makes it possible to analyse the microscopic changes in thermodynamics. The research results were recently published in Physical Review Letters (“On-Chip Maxwell’s Demon as an Information-Powered Refrigerator”). The work is part of the forthcoming PhD thesis of MSc Jonne Koski at Aalto University.

An image illustrating the theory underlying the proposed device has been made available,

An autonomous Maxwell's demon. When the demon sees the electron enter the island (1.), it traps the electron with a positive charge (2.). When the electron leaves the island (3.), the demon switches back a negative charge (4.). Image: Jonne Koski.

An autonomous Maxwell’s demon. When the demon sees the electron enter the island (1.), it traps the electron with a positive charge (2.). When the electron leaves the island (3.), the demon switches back a negative charge (4.). Image: Jonne Koski.

A Jan. 11, 2016 Aalto University press release, which originated the news item, provides more technical details,

The system we constructed is a single-electron transistor that is formed by a small metallic island connected to two leads by tunnel junctions made of superconducting materials. The demon connected to the system is also a single-electron transistor that monitors the movement of electrons in the system. When an electron tunnels to the island, the demon traps it with a positive charge. Conversely, when an electron leaves the island, the demon repels it with a negative charge and forces it to move uphill contrary to its potential, which lowers the temperature of the system,’ explains Professor Jukka Pekola.

What makes the demon autonomous or self-contained is that it performs the measurement and feedback operation without outside help. Changes in temperature are indicative of correlation between the demon and the system, or, in simple terms, of how much the demon ‘knows’ about the system. According to Pekola, the research would not have been possible without the Low Temperature Laboratory conditions.

‘We work at extremely low temperatures, so the system is so well isolated that it is possible to register extremely small temperature changes,’ he says.

‘An electronic demon also enables a very large number of repetitions of the measurement and feedback operation in a very short time, whereas those who, elsewhere in the world, used molecules to construct their demons had to contend with not more than a few hundred repetitions.’

The work of the team led by Pekola remains, for the time being, basic research, but in the future, the results obtained may, among other things, pave the way towards reversible computing.

‘As we work with superconducting circuits, it is also possible for us to create qubits of quantum computers. Next, we would like to examine these same phenomena on the quantum level,’ Pekola reveals.

Here’s a link to and a citation for the paper,

On-Chip Maxwell’s Demon as an Information-Powered Refrigerator by J.V. Koski, A. Kutvonen, I.M. Khaymovich, T. Ala-Nissila, and J.P. Pekola. Phys. Rev. Lett. 115, 260602 DOI: http://dx.doi.org/10.1103/PhysRevLett.115.260602 Published 30 December 2015

This paper is behind a paywall.

One final comment, this is the 150th anniversary of Maxwell’s publication of a series of equations explaining the relationships between electric charges and electric and magnetic fields (featured here in a Nov. 27, 2015 posting).

The search for James Clerk Maxwell

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The Brits really know how to celebrate an anniversary. In this case it’s the 150th anniversary of James Clerk Maxwell’s electromagnetic theory unifying electricity, magnetism, and light. (My Nov. 27, 2015 posting the first piece here featuring the anniversary and it describes the theory in more detail than you’ll find here.)

As part of the celebration there’s a five-episode series titled: Self Drives: Maxwell’s Equations being broadcast on BBC (British Broadcasting Corporation) 4. Stephen Curry writes about the series in a Dec. 9, 2015 posting on the Guardian science blogs (Note: Links have been removed),

There’s a potent antidote to the “Isn’t this amazing?” school of science communication and it’s called Will Self. In Self Drives: Maxwell’s Equations, which was broadcast recently [you can hear it as a podcast by visiting this site] on BBC Radio 4, the curious curmudgeon takes science to task once again as he goes in search of the mathematical and physical genius behind James Clerk Maxwell.

Over five short episodes, Self’s querulous quest takes him from Maxwell’s birthplace in Edinburgh to his family home in Glenlair, to the radio telescope at Jodrell Bank and the Diamond synchrotron near Oxford, and finally to Cambridge, where Maxwell studied mathematics in his youth and returned in his latter years as one of the nation’s most accomplished scientists to head the university’s Cavendish physics laboratory. Accompanying Self along the way is Akram Khan, the same physics professor who joined the errant writer on his earlier orbit of the Large Hadron Collider at CERN. I would have dubbed Khan Sancho Panza to Self’s Don Quixote but for this particular expedition the characters are reversed. It is Khan who wishes to see the poetry of science, while Self is happier to be grounded in prosaic and flawed reality. At CERN he refused truculently to worship in the cathedral of particle physics, stymied in equal measure by the difficulty of the subject matter and the boosterism of its scientific proponents. Here again the journey is mostly one of disappointment and frustration.

But not for the listener. The quest is far from fruitless, and nor is it lacking in emotional and intellectual force. Self’s documentary is not straight biography – you will find out more about Maxwell’s life and work from Wikipedia – but he has a different target in mind. …

Here’s the pair of explorers,

Will Self, Akram Khan and Maxwell’s infamous equations. Photograph: Laurence Grissell/BBC

Will Self, Akram Khan and Maxwell’s infamous equations. Photograph: Laurence Grissell/BBC

It’s good writing and an intriguing look into communicating science in a way that’s not quite so reverent and/or kid friendly as we tend to be in Canada.

James Clerk Maxwell and his science mashup unified theories of magnetism, electricity, and optics

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It’s the 150th anniversary for a series of equations electric charges and electric and magnetic fields that are still being explored. Jon Butterworth in a Nov. 22, 2015 posting on the Guardian science blog network explains (Note: A link has been removed),

The chances are that you are reading this article on some kind of electronic technology. You are definitely seeing it via visible light, unless you have a braille or audio converter. And it probably got to you via wifi or a mobile phone signal. All of those things are understood in terms of the relationships between electric charges and electric and magnetic fields summarised in Maxwell’s [James Clerk Maxwell] equations, published by the Royal Society in 1865, 150 years ago.

Verbally, the equations can be summarised as something like:

Electric and magnetic fields make electric charges move. Electric charges cause electric fields, but there are no magnetic charges. Changes in magnetic fields cause electric fields, and vice versa.

The equations specify precisely how it all happens, but that is the gist of it.

Butterworth got a rare opportunity to see the original manuscript,

Original manuscript of Maxwell’s seminal paper Photograph: Jon Butterworth/Royal Society [downloaded from http://www.theguardian.com/science/life-and-physics/2015/nov/22/maxwells-equations-150-years-of-light]

Original manuscript of Maxwell’s seminal paper Photograph: Jon Butterworth/Royal Society [downloaded from http://www.theguardian.com/science/life-and-physics/2015/nov/22/maxwells-equations-150-years-of-light]

I love this description from Butterworth,

It was submitted in 1864 but, in a situation familiar to scientists everywhere, was held up in peer review. There’s a letter, dated March 1865, from William Thomson (later Lord Kelvin) saying he was sorry for being slow, that he’d read most of it and it seemed pretty good (“decidely suitable for publication”).

Then, there’s this,

The equations seem to have been very much a bottom-up affair, in that Maxwell collected together a number of known laws which were used to describe various experimental results, and (with a little extra ingredient of his own) fitted them into a unified framework. What is amazing is how much that framework then reveals, both in terms of deep physical principles, and rich physical phenomena.

I’m not excerpting any part of Butterworth’s description of how Maxwell fit these equations together for his unification theory as I think it should be read in its totality.

The section on quantum mechanics is surprising,

Now, one thing Maxwell’s equations don’t contain is quantum mechanics [emphasis mine]. They are classical equations. But if you take the quantum mechnical description of an electron, and you enforce the same charge conservation law/voltage symmetry that was contained in the classical Maxwell’s equations, something marvellous happens [emphasis mine]. The symmetry is denoted “U(1)”, and if you enforce it locally – that it, you say that you have to be allowed make different U(1) type changes to electrons at different points in space, you actually generate the quantum mechanical version of Maxwell’s equations out of nowhere [emphasis mine]. You produce the equations that describe the photon, and the whole of quantum electrodynamics.

I encourage you to read Butterworth’s Nov. 22, 2015 posting where he also mention two related art/science projects and has embedded a video animation of the principles discussed in his posting.

For anyone unfamiliar with Butterworth, there’s this description at the Guardian,

Jon Butterworth is a physics professor at University College London. He is a member of the UCL High Energy Physics group and works on the Atlas experiment at Cern’s Large Hadron Collider. His book Smashing Physics: The Inside Story of the Hunt for the Higgs was published in May 2014

A nanoscale bacteria power grid

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It’s not often you see the word ‘spectacular’ when reading a science news item but it can be found in an Oct. 21, 2015 news item on ScienceDaily,

Electrical energy from the socket — this convenient type of power supply is apparently used by some microorganisms. Cells can meet their energy needs in the form of electricity through nano-wire connections. Researchers from the Max Planck Institute for Marine Microbiology in Bremen have discovered these possibly smallest power grids in the world when examining cell aggregates of methane degrading microorganisms. They consist of two completely different cell types, which can only jointly degrade methane. Scientists have discovered wire-like connections between the cells, which are relevant in energy exchanges.

It was a spectacular [emphasis mine] scientific finding when researchers discovered electrical wiring between microorganisms using iron as energy source in 2010. Immediately the question came up if electric power exchange is common in other microbially mediated reactions. One of the processes in question was the anaerobic oxidation of methane (AOM) that is responsible for the degradation of the greenhouse gas methane in the seafloor, and therefore has a great relevance for Earth climate. The microorganisms involved have been described for the first time in 2000 by researchers from Bremen and since then have been extensively studied.

This image accompanies the research,

Caption: Electron micrograph of the nanowires shows connecting archaea and sulphate reducing bacteria. The wires stretch out for several micrometres, longer than a single cell. The white bar represents the length of one micrometre. The arrows indicate the nanowires (A=ANME-Archaeen, H=HotSeep-1 partner bacteria). Credit: MPI f. Biophysical Chemistry

Caption: Electron micrograph of the nanowires shows connecting archaea and sulphate reducing bacteria. The wires stretch out for several micrometres, longer than a single cell. The white bar represents the length of one micrometre. The arrows indicate the nanowires (A=ANME-Archaeen, H=HotSeep-1 partner bacteria).
Credit: MPI f. Biophysical Chemistry

A Oct. 21, 2015 Max Planck press release (also on EurekAlert), which originated the news item, provides more information about methane in the ocean, power wires, and electron transporters,

In the ocean, methane is produced from the decay of dead biomass in subsurface sediments. The methane rises upwards to the seafloor, but before reaching the water column it is degraded by special consortia of archaea and bacteria. The archaea take up methane and oxidise it to carbonate. They pass on energy to their partner bacteria, so that the reaction can proceed. The bacteria respire sulphate instead of oxygen to gain energy (sulphate reducers). This may be an ancient metabolism, already relevant billions of years ago when the Earth’s atmosphere was oxygen-free. Yet today it remains unknown how the anaerobic oxidation of methane works biochemically.

Gunter Wegener, who authors the publication together with PhD student Viola Krukenberg, says: “We focused on thermophilic AOM consortia living at 60 degrees Celsius. For the first time we were able to isolate the partner bacteria to grow them alone. Then we systematically compared the physiology of the isolate with that of the AOM culture. We wanted to know which substances can serve as an energy carrier between the archaea and sulphate reducers.” Most compounds were ruled out quickly. At first, hydrogen was considered as energy source. However, the archaea did not produce sufficient hydrogen to explain the growth of sulphate reducers – hence the researchers had to change their strategy.

Direct power wires and electron transporters

One possible alternative was to look for direct connections channelling electrons between the cells. Using electron microscopy on the thermophilic AOM cultures this idea was confirmed. Dietmar Riedel, head of electron microscopy facilities at the Max Planck Institute in Goettingen says: “It was really challenging to visualize the cable-like structures. We embedded aggregates under high pressure using different embedding media. Ultrathin sections of these aggregates were then examined in near-native state using transmission electron microscopy.”

Viola Krukenberg adds: “We found all genes necessary for biosynthesis of the cellular connections called pili. Only when methane is added as energy source these genes are activated and pili are formed between bacteria and archaea.”

With length of several micrometres the wires can exceed the length of the cells by far, but their diameter is only a few nanometres. These wires provide the contact between the closely spaced cells and explain the spatial structure of the consortium, as was shown by a team of researchers led by Victoria Orphan from Caltech.

“Consortia of archaea and bacteria are abundant in nature. Our next step is to see whether other types also show such nanowire-like connections. It is important to understand how methane-degrading microbial consortia work, as they provide important functions in nature”, explains Antje Boetius, leader of the research group at the Institute in Bremen.

Here’s a link to and a citation for the paper,

Intercellular wiring enables electron transfer between methanotrophic archaea and bacteria by Gunter Wegener, Viola Krukenberg, Dietmar Riedel, Halina E. Tegetmeyer, & Antje Boetius. Nature 526, 587–590 (22 October 2015) doi:10.1038/nature15733 Published online 21 October 2015

This paper is behind a paywall.

US Navy invests in graphene

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More usually, I feature research from DARPA (Defense Advanced Research Progects Agency) which I think belongs to the US Army and the US Air Force Research Office. The US Navy has featured here only once before (a Nov. 1, 2011 posting) and even then it was tangentially. I think it’s long past time that the US Navy gets some attention.

A July 22, 2015 news item on Nanowerk explains the Navy’s interest in electricity and graphene,

The U.S. Navy distributes electricity aboard most of its ships like a power company. It relies on conductors, transformers and other bulky infrastructure.

The setup works, but with powerful next generation weapons on the horizon and the omnipresent goal of energy efficiency, the Navy is seeking alternatives to conventional power control systems.

One option involves using graphene, which, since its discovery in 2004, has become the material of choice for researchers working to improve everything from solar cells to smartphone batteries.

Accordingly, the Office of Naval Research has awarded University at Buffalo engineers an $800,000 grant to develop narrow strips of graphene called nanoribbons that may someday revolutionize how power is controlled in ships, smartphones and other electronic devices.

A July 20, 2015 University of Buffalo news release by Cory Nealon, which originated the news item, expands on the theme,

“We need to develop new nanomaterials capable of handling greater amounts of energy densities in much smaller devices. Graphene nanoribbons show remarkable promise in this endeavor,” says Cemal Basaran, PhD, a professor in UB’s Department of Civil, Structural and Environmental Engineering, School of Engineering and Applied Sciences, and the grant’s principal investigator.

Graphene is a single layer of carbon atoms packed together like a honeycomb. It is extremely thin, light and strong. It’s also the best known conductor of heat and electricity.

“The beauty of graphene is that it can be grown like biological organisms as opposed to manufacturing materials with traditional techniques,” says Basaran, director of UB’s Electronic Packaging Laboratory and a researcher in UB’s New York State Center of Excellence in Materials Informatics. “These bio-inspired materials allow us to control their atomic organizations like controlling genetic DNA makeup of a lab-grown cell.”

While promising, researchers are just beginning to understand graphene and its potential uses. One area of interest is power control systems.

Like overhead power lines, most ships rely on copper or other metals to move electricity. Unfortunately, this process is relatively inefficient; electrons bash into each other and create heat in a process called Joule heating.

“You lose a great deal of energy that way,” Basaran says. “With graphene, you avoid those collisions because it conducts electricity in a different process, known as semi-ballistic conduction. It’s like a high-speed bullet train versus bumper cars.”

Another limitation of metal-based power distribution is the bulky infrastructure – transistors, copper wires, transformers, etc. – needed to move electricity. Whether in a ship or tablet computer, the components take up space and add weight.

Graphene nanoribbons offer a potential solution because they can act as both a conductor (instead of copper) and semiconductor (instead of silicon). Moreover, their ability to withstand failure under extreme energy loads is roughly 1,000 times greater than copper.

That bodes well for the Navy, which, like segments of the automotive industry, is pivoting toward electric vehicles.

It recently launched an all-electric destroyer; the ship’s propellers and drive shafts are turned by electric motors, as opposed to being connected to combustion engines. The integrated power-generation and distribution system may also be used to fire next generation weapons, such as railguns and powerful lasers. And the automation has allowed the Navy to reduce the ship’s crew, which places fewer sailors in potentially dangerous situations.

Graphene nanoribbons could improve these systems by making them more robust and energy-efficient, Basaran said. He and a team of researchers will:

·         Design complex simulations that examine how graphene nanoribbons can be used as a power switch.

·         Explore how adding hydrogen and other elements, a process known as “doping,” to graphene nanoribbons could improve their performance.

·         Investigate graphene nanoribbons’ failure limit under high power loads and try to find ways to improve it.

The research will be performed over the next four years.

I was particularly intrigued by the caption for this image included with the news release,

The technology may lead to more powerful weapons, energy savings and reduced crew numbers [Downloaded from http://www.buffalo.edu/news/releases/2015/07/021.html]

The technology may lead to more powerful weapons, energy savings and reduced crew numbers [Downloaded from http://www.buffalo.edu/news/releases/2015/07/021.html]

Presumably “reduced crew numbers’ means fewer jobs. I wonder if they’ll figure out that people without jobs are without money to pay taxes to fund these projects.