Monthly Archives: July 2016

First carbon nanotube mirrors for Cubesat telescope

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A July 12, 2016 news item on phys.org describes a project that could lead to the first carbon nanotube mirrors to be used in a Cubesat telescope in space,

A lightweight telescope that a team of NASA scientists and engineers is developing specifically for CubeSat scientific investigations could become the first to carry a mirror made of carbon nanotubes in an epoxy resin.

Led by Theodor Kostiuk, a scientist at NASA’s [US National Aeronautics and Space Administration] Goddard Space Flight Center in Greenbelt, Maryland, the technology-development effort is aimed at giving the scientific community a compact, reproducible, and relatively inexpensive telescope that would fit easily inside a CubeSat. Individual CubeSats measure four inches on a side.

John Kolasinski (left), Ted Kostiuk (center), and Tilak Hewagama (right) hold mirrors made of carbon nanotubes in an epoxy resin. The mirror is being tested for potential use in a lightweight telescope specifically for CubeSat scientific investigations. Credit: NASA/W. Hrybyk

John Kolasinski (left), Ted Kostiuk (center), and Tilak Hewagama (right) hold mirrors made of carbon nanotubes in an epoxy resin. The mirror is being tested for potential use in a lightweight telescope specifically for CubeSat scientific investigations. Credit: NASA/W. Hrybyk

A July 12, 2016 US National Aeronautics and Space Administration (NASA) news release, which originated the news item, provides more information about Cubesats,

Small satellites, including CubeSats, are playing an increasingly larger role in exploration, technology demonstration, scientific research and educational investigations at NASA. These miniature satellites provide a low-cost platform for NASA missions, including planetary space exploration; Earth observations; fundamental Earth and space science; and developing precursor science instruments like cutting-edge laser communications, satellite-to-satellite communications and autonomous movement capabilities. They also allow an inexpensive means to engage students in all phases of satellite development, operation and exploitation through real-world, hands-on research and development experience on NASA-funded rideshare launch opportunities.

Under this particular R&D effort, Kostiuk’s team seeks to develop a CubeSat telescope that would be sensitive to the ultraviolet, visible, and infrared wavelength bands. It would be equipped with commercial-off-the-shelf spectrometers and imagers and would be ideal as an “exploratory tool for quick looks that could lead to larger missions,” Kostiuk explained. “We’re trying to exploit commercially available components.”

While the concept won’t get the same scientific return as say a flagship-style mission or a large, ground-based telescope, it could enable first order of scientific investigations or be flown as a constellation of similarly equipped CubeSats, added Kostiuk.

With funding from Goddard’s Internal Research and Development program, the team has created a laboratory optical bench made up of three commercially available, miniaturized spectrometers optimized for the ultraviolet, visible, and near-infrared wavelength bands. The spectrometers are connected via fiber optic cables to the focused beam of a three-inch diameter carbon-nanotube mirror. The team is using the optical bench to test the telescope’s overall design.

The news release then describes the carbon nanotube mirrors,

By all accounts, the new-fangled mirror could prove central to creating a low-cost space telescope for a range of CubeSat scientific investigations.

Unlike most telescope mirrors made of glass or aluminum, this particular optic is made of carbon nanotubes embedded in an epoxy resin. Sub-micron-size, cylindrically shaped, carbon nanotubes exhibit extraordinary strength and unique electrical properties, and are efficient conductors of heat. Owing to these unusual properties, the material is valuable to nanotechnology, electronics, optics, and other fields of materials science, and, as a consequence, are being used as additives in various structural materials.

“No one has been able to make a mirror using a carbon-nanotube resin,” said Peter Chen, a Goddard contractor and president of Lightweight Telescopes, Inc., a Columbia, Maryland-based company working with the team to create the CubeSat-compatible telescope.

“This is a unique technology currently available only at Goddard,” he continued. “The technology is too new to fly in space, and first must go through the various levels of technological advancement. But this is what my Goddard colleagues (Kostiuk, Tilak Hewagama, and John Kolasinski) are trying to accomplish through the CubeSat program.”

…

The use of a carbon-nanotube optic in a CubeSat telescope offers a number of advantages, said Hewagama, who contacted Chen upon learning of a NASA Small Business Innovative Research program awarded to Chen’s company to further advance the mirror technology. In addition to being lightweight, highly stable, and easily reproducible, carbon-nanotube mirrors do not require polishing — a time-consuming and often times expensive process typically required to assure a smooth, perfectly shaped mirror, said Kolasinski, an engineer and science collaborator on the project.

To make a mirror, technicians simply pour the mixture of epoxy and carbon nanotubes into a mandrel or mold fashioned to meet a particular optical prescription. They then heat the mold to to cure and harden the epoxy. Once set, the mirror then is coated with a reflective material of aluminum and silicon dioxide.

“After making a specific mandrel or mold, many tens of identical low-mass, highly uniform replicas can be produced at low cost,” Chen said. “Complete telescope assemblies can be made this way, which is the team’s main interest. For the CubeSat program, this capability will enable many spacecraft to be equipped with identical optics and different detectors for a variety of experiments. They also can be flown in swarms and constellations.”

There could be other applications for these carbon nanotube mirrors according to the news release,

A CubeSat telescope is one possible application for the optics technology, Chen added.

He believes it also would work for larger telescopes, particularly those comprised of multiple mirror segments. Eighteen hexagonal-shape mirrors, for example, form the James Webb Space Telescope’s 21-foot primary mirror and each of the twin telescopes at the Keck Observatory in Mauna Kea, Hawaii, contain 36 segments to form a 32-foot mirror.

Many of the mirror segments in these telescopes are identical and can therefore be produced using a single mandrel. This approach avoids the need to grind and polish many individual segments to the same shape and focal length, thus potentially leading to significant savings in schedule and cost.

Moreover, carbon-nanotube mirrors can be made into ‘smart optics’. To maintain a single perfect focus in the Keck telescopes, for example, each mirror segment has several externally mounted actuators that deform the mirrors into the specific shapes required at different telescope orientations.

In the case of carbon-nanotube mirrors, the actuators can be formed into the optics at the time of fabrication. This is accomplished by applying electric fields to the resin mixture before cure, which leads to the formation of carbon-nanotube chains and networks. After curing, technicians then apply power to the mirror, thereby changing the shape of the optical surface. This concept has already been proven in the laboratory.

“This technology can potentially enable very large-area technically active optics in space,” Chen said. “Applications address everything from astronomy and Earth observing to deep-space communications.”

Dexter Johnson provides some additional tidbits in his July 14, 2016 post (on his Nanoclast blog on the IEEE [Institute for Electrical and Electronics Engineers] about the Cubesat mirrors.

Beatrix Potter and her science on her 150th birthday

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July 28, 2016 was the 150th anniversary of Beatrix Potter‘s birthday. Known by many through her children’s books, she has left an indelible mark on many of us. Hop-skip-jump.com has a description of an extraordinary woman, from their Beatrix Potter 150 years page,

An artist, storyteller, botanist, environmentalist, farmer and impeccable businesswoman, Potter was a visionary and a trailblazer. Single-mindedly determined and ambitious she overcame professional rejection, academic humiliation, and personal heartbreak, going on to earn her fortune and a formidable reputation.

A July 27, 2016 posting by Alex Jackson on the Guardian science blogs provides more information about Potter’s science (Note: Links have been removed),

Influenced by family holidays in Scotland, Potter was fascinated by the natural world from a young age. Encouraged to follow her interests, she explored the outdoors with sketchbook and camera, honing her skills as an artist, by drawing and sketching her school room pets: mice, rabbits and hedgehogs. Led first by her imagination, she developed a broad interest in the natural sciences: particularly archaeology, entomology and mycology, producing accurate watercolour drawings of unusual fossils, fungi, and archaeological artefacts.

Potter’s uncle, Sir Henry Enfield Roscoe FRS, an eminent nineteenth-century chemist, recognised her artistic talent and encouraged her scientific interests. By the 1890s, Potter’s skills in mycology drew Roscoe’s attention when he learned she had successfully germinated spores of a class of fungi, and had ideas on how they reproduced. He used his scientific connections with botanists at Kew’s Royal Botanic Gardens to gain a student card for his niece and to introduce her to Kew botanists interested in mycology.

Although Potter had good reason to think that her success might break some new ground, the botanists at Kew were sceptical. One Kew scientist, George Massee, however, was sufficiently interested in Potter’s drawings, encouraging her to continue experimenting. Although the director of Kew, William Thistleton-Dyer refused to give Potter’s theories or her drawings much attention both because she was an amateur and a female, Roscoe encouraged his niece to write up her investigations and offer her drawings in a paper to the Linnean Society.

In 1897, Potter put forward her paper, which Massee presented to the Linnean Society, since women could not be members or attend a meeting. Her paper, On the Germination of the Spores of the Agaricineae, was not given much notice and she quickly withdrew it, recognising that her samples were likely contaminated. Sadly, her paper has since been lost, so we can only speculate on what Potter actually concluded.

…

Until quite recently, Potter’s accomplishments and her experiments in natural science went unrecognised. Upon her death in 1943, Potter left hundreds of her mycological drawings and paintings to the Armitt Museum and Library in Ambleside, where she and her husband had been active members. Today, they are valued not only for their beauty and precision, but also for the assistance they provide modern mycologists in identifying a variety of fungi.

In 1997, the Linnean Society issued a posthumous apology to Potter, noting the sexism displayed in the handling of her research and its policy toward the contributions of women.

A rarely seen very early Beatrix Potter drawing, A Dream of Toasted Cheese was drawn to celebrate the publication of Henry Roscoe’s chemistry textbook in 1899. Illustration: Beatrix Potter/reproduced courtesy of the Lord Clwyd collection (image by way of The Guardian newspaper)

A rarely seen very early Beatrix Potter drawing, A Dream of Toasted Cheese was drawn to celebrate the publication of Henry Roscoe’s chemistry textbook in 1899. Illustration: Beatrix Potter/reproduced courtesy of the Lord Clwyd collection (image by way of The Guardian newspaper)

I’m sure you recognized the bunsen burner. From the James posting (Note: A link has been removed),

London-born, Henry Roscoe, whose family roots were in Liverpool, studied at University College London, before moving to Heidelberg, Germany, where he worked under Robert Bunsen, inventor of the new-fangled apparatus that inspired Potter’s drawing. Together, using magnesium as a light source, Roscoe and Bunsen reputedly carried out the first flashlight photography in 1864. Their research laid the foundations of comparative photochemistry.

These excerpts do not give full justice to James’ piece which I encourage you to read in its entirety.

Should you be going to the UK and inclined to follow up further, there’s a listing of 2016 events being held to honour Potter on the UK National Trust’s Celebrating Beatrix Potter’s anniversary in the Lake District webpage.

Putting a gold atom in a silver nanocluster changes things

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Considering that the King Abdullah University of Science and Technology (KAUST) opened on Sept. 23, 2009 (mentioned in my Sept. 24, 2009 post; scroll down about 50% of the way), the university has done a remarkable job of establishing itself within the research community. Here’s some of the latest news from KAUST in a July 15, 2016 news item on Nanowerk,

The appearance of metals, such as their shiny surface or their electrical conductivity, is determined by the ensemble of atoms that comprise the metal. The situation differs on the molecular scale, and KAUST researchers have shown that replacing a single atom in a cluster of 25 silver atoms with one gold atom fundamentally changes its properties …

Composing a silver nanocrystal: the center silver atom (a) surrounded by a cage of 12 other silver atoms (b) embedded by further atoms (c) and stabilized by further ligands (d). Reproduced with permission from ref 1.© 2016 John Wiley and Sons.

Composing a silver nanocrystal: the center silver atom (a) surrounded by a cage of 12 other silver atoms (b) embedded by further atoms (c) and stabilized by further ligands (d). Reproduced with permission from ref 1.© 2016 John Wiley and Sons.

A July (??), 2016 KAUST news release, which originated the news item, provides more detail,

Metal atom nanoclusters are made from a core of a few metal atoms surrounded by a protective shell of stabilizing ligands. Nanoclusters come in different sizes, but each stable variation of nanoclusters has exactly the same number of metal atoms. This leads to very controllable properties, noted Osman Bakr, KAUST associate professor of material science and engineering and leader of the research team.

“Nanoclusters have unique arrangements of atoms and size-dependent absorption, fluorescence, electronic and catalytic properties,” he said.

A popular metal nanocluster is [Ag25(SR)18]–, which consists of of 25 silver atoms. This nanocluster is unique as it corresponds to a gold nanocluster that has exactly the same number of atoms. Both clusters have different properties due to the different metal used. To understand how exactly the atomic composition affects these properties, the researchers replaced a single silver atom with gold.

Replacing a single atom in a nanocluster is a difficult task. Direct chemical methods can be used, but these give little control over how many atoms are replaced, making it difficult to ascribe particular properties to the nanocluster structure.

Instead, the researchers used a galvanic replacement process that relies on difference in the electrochemical potential between the incoming and outgoing atoms to induce atomic replacements. To their surprise, the process produced a reliable and precise atomic exchange in which only the center silver atom is replaced by gold.

The replacement yielded dramatic changes in the nanocluster. A solution of the silver nanoclusters appears orange, whereas after the replacement of the central atom the color turns dark green.

This indicates more fundamental changes in properties, Bakr said. “The ambient stability and fluorescence of the nanocluster were enhanced by a factor of 25 as a result of this single atom replacement. Furthermore, we are now able to demonstrate the importance of a single atom impurity on nanoparticles and modulate the properties at the single atom level,” he noted.

The reliable replacement of only a single gold atom opens the door to a more systematic investigation of metal nanoclusters, which can help to uncover the mechanisms of the chemical and physical changes arising from the replacement.

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

Templated Atom-Precise Galvanic Synthesis and Structure Elucidation of a [Ag24Au(SR)18]− Nanocluster by Dr. Megalamane S. Bootharaju, Chakra P. Joshi, Dr. Manas R. Parida, Prof. Omar F. Mohammed and Prof. Osman M. Bakr. Angewandte Chemie International Edition DOI: 10.1002/anie.201509381 Version of Record online: 27 NOV 2015

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

They’ve certainly waited a while to tout this research. Ah well. This paper is behind a paywall.

A carbon nanotube ‘bridge’ for nerves

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Italian researchers have developed a three-dimensional carbon nanotube sponge (or bridge) that could be used in conjunction with neural explants according to a July 15, 2016 SISSA press release (also on EurekAlert), which describes the work,

A complex study, lasting several years and involving work groups with specialties in various fields, has shown that a new material (a three-dimensional sponge made of carbon nanotubes) supports the growth of nerve fibers, bridging segregated neural explants and providing a functional re-connection. The study, which was coordinated by the International School for Advanced Studies (SISSA) in Trieste, in collaboration with the University of Rome Tor Vergata and the University of Trieste, also observed biocompatibility in vivo of the material, demonstrating that implanting it into  the brain of small rodents does not cause large scars or a marked immune response.

“Under the microscope, it looks like a knotted tangle of tubes. It was initially studied by Maurizio De Crescenzi’s team at the University of Rome Tor Vergata for cleaning up spilled hydrocarbons in the sea,” explains Laura Ballerini, SISSA Professor and coordinator of the recently-published study. It was Maurizio Prato’s intuition, however, that pushed them to investigate the possibility of applying such a material to nerve tissue. The idea of developing the hybrids of neurons and nano-materials was the result of a long-term project and collaboration between Prato (University of Trieste) and Ballerini’s (SISSA) groups.

In the present study, Ballerini and her team first investigated the material’s reaction to nerve tissue in vitro. “We explanted two spinal cord segments and cultured them together but separated by 300 microns,” says Sadaf Usmani, a PhD student at the School and first author of the study. “In those conditions, without any scaffolds reconstructing the space between the two explants, we observed growth of nerve fibers which extended in a straight bundles in any direction, but not necessarily towards the other tissue. If we insert a small piece of the carbon sponge into the space between the two, however, we see dense growth of nerve fibers that fill the structure and intertwine with the other sample.”

“Observing fiber reaching the contralateral explant is not enough, however,” points out University of Trieste researcher and one of the authors of the study, Denis Scaini. “You have to show that there is a functional connection between the two populations of neurons.” For this, SISSA Professor, David Zoccolan and his team’s contribution was crucial. “With signal analysis techniques they had already developed, we were able to demonstrate two things: first, that spontaneous nervous activity in the two samples was actually correlated, indicating a connection, that was not there when the sponge was absent, and second,, that by applying an electrical signal to one of the samples, the activity of the second sample could be triggered, but only when the nanotubes were present.”

Tests for Biocompatibility

The results in the lab were extremely positive. But this was not sufficient for Ballerini and her colleagues. “In order to continue to invest additional energy and resources to the study for potential applications, is crucial to test if the material is accepted by living organisms without negative consequences,” says Ballerini.

To perform these tests, Ballerini’s team worked closely with SISSA Post-Doc researcher, and member of Zoccolan’s team, Federica Rosselli. “We implanted small portions of the material into the brain of healthy rodents. After four weeks, we observed that the material was well tolerated. There were limited scars, as well as low immune responses, some biological indicators even showed that there could be positive implications. There was also a progressive invasion of neurons within the sponge. The rats were vital and healthy during the entire four weeks,” says Usmani.

“In conclusion,” says Ballerini, “the excellent results at the structural and functional level in vitro and in vivo showed biocompatibility are encouraging us to continue this line of research. These materials could be useful for covering electrodes used for treating movement disorders like Parkinson’s because they are well accepted by tissue, while the implants being used today become less effective over time because of scar tissue. We hope this encourages other research teams with multidisciplinary expertise to expand this type of study even further.”

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

3D meshes of carbon nanotubes guide functional reconnection of segregated spinal explants by Sadaf Usmani, Emily Rose Aurand, Manuela Medelin, Alessandra Fabbro, Denis Scaini, Jummi Laishram, Federica B. Rosselli, Alessio Ansuini, Davide Zoccola1, Manuela Scarselli, Maurizio De Crescenzi, Susanna Bosi, Maurizio Prato, and Laura Ballerini. Science Advances  15 Jul 2016: Vol. 2, no. 7, e1600087 DOI: 10.1126/sciadv.1600087 Published 01 July 2016

This paper is open access.

H/t July 15, 2016 news item on phys.org.

Synthetic biowire for nanoelectronics

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Apparently this biowire derived by synthetic biology processes can make nanoelectronics a greener affair. From a July 14, 2016 news item on ScienceDaily,

Scientists at the University of Massachusetts Amherst report in the current issue of Small that they have genetically designed a new strain of bacteria that spins out extremely thin and highly conductive wires made up of solely of non-toxic, natural amino acids.

A July 14, 2016 University of Massachusetts at Amherst news release (also on EurekAlert), which originated the news item, provides more information,

Researchers led by microbiologist Derek Lovley say the wires, which rival the thinnest wires known to man, are produced from renewable, inexpensive feedstocks and avoid the harsh chemical processes typically used to produce nanoelectronic materials.

Lovley says, “New sources of electronic materials are needed to meet the increasing demand for making smaller, more powerful electronic devices in a sustainable way.” The ability to mass-produce such thin conductive wires with this sustainable technology has many potential applications in electronic devices, functioning not only as wires, but also transistors and capacitors. Proposed applications include biocompatible sensors, computing devices, and as components of solar panels.

This advance began a decade ago, when Lovley and colleagues discovered that Geobacter, a common soil microorganism, could produce “microbial nanowires,” electrically conductive protein filaments that help the microbe grow on the iron minerals abundant in soil. These microbial nanowires were conductive enough to meet the bacterium’s needs, but their conductivity was well below the conductivities of organic wires that chemists could synthesize.

“As we learned more about how the microbial nanowires worked we realized that it might be possible to improve on Nature’s design,” says Lovley. “We knew that one class of amino acids was important for the conductivity, so we rearranged these amino acids to produce a synthetic nanowire that we thought might be more conductive.”

The trick they discovered to accomplish this was to introduce tryptophan, an amino acid not present in the natural nanowires. Tryptophan is a common aromatic amino acid notorious for causing drowsiness after eating Thanksgiving turkey. However, it is also highly effective at the nanoscale in transporting electrons.

“We designed a synthetic nanowire in which a tryptophan was inserted where nature had used a phenylalanine and put in another tryptophan for one of the tyrosines. We hoped to get lucky and that Geobacter might still form nanowires from this synthetic peptide and maybe double the nanowire conductivity,” says Lovley.

The results greatly exceeded the scientists’ expectations. They genetically engineered a strain of Geobacter and manufactured large quantities of the synthetic nanowires 2000 times more conductive than the natural biological product. An added bonus is that the synthetic nanowires, which Lovley refers to as “biowire,” had a diameter only half that of the natural product.

“We were blown away by this result,” says Lovley. The conductivity of biowire exceeds that of many types of chemically-produced organic nanowires with similar diameters. The extremely thin diameter of 1.5 nanometers (over 60,000 times thinner than a human hair) means that thousands of the wires can easily be packed into a very small space.

The added benefit is that making biowire does not require any of the dangerous chemicals that are needed for synthesis of other nanowires. Also, biowire contains no toxic components. “Geobacter can be grown on cheap renewable organic feedstocks so it is a very ‘green’ process,” he notes. And, although the biowire is made out of protein, it is extremely durable. In fact, Lovley’s lab had to work for months to establish a method to break it down.

“It’s quite an unusual protein,” Lovley says. “This may be just the beginning” he adds. Researchers in his lab recently produced more than 20 other Geobacter strains, each producing a distinct biowire variant with new amino acid combinations. He notes, “I am hoping that our initial success will attract more funding to accelerate the discovery process. We are hoping that we can modify biowire in other ways to expand its potential applications.”

As it often does, funding provides some notes of interest,

This research was supported by the Office of Naval Research, the National Science Foundation’s Nanoscale Science and Engineering Center and the UMass Amherst Center for Hierarchical Manufacturing.

Caption: Synthetic biowire are making an electrical connection between two electrodes. Researchers led by microbiologist Derek Lovely at UMass Amherst say the wires, which rival the thinnest wires known to man, are produced from renewable, inexpensive feedstocks and avoid the harsh chemical processes typically used to produce nanoelectronic materials. Credit: UMass Amherst

Caption: Synthetic biowire are making an electrical connection between two electrodes. Researchers led by microbiologist Derek Lovely at UMass Amherst say the wires, which rival the thinnest wires known to man, are produced from renewable, inexpensive feedstocks and avoid the harsh chemical processes typically used to produce nanoelectronic materials. Credit: UMass Amherst

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

Synthetic Biological Protein Nanowires with High Conductivity by Yang Tan, Ramesh Y. Adhikari, Nikhil S. Malvankar, Shuang Pi, Joy E. Ward, Trevor L. Woodard, Kelly P. Nevin, Qiangfei Xia, Mark T. Tuominen, and Derek R. Lovley. Small DOI: 10.1002/smll.201601112 Version of Record online: 13 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 couple of Frankenstein dares from The Frankenstein Bicentennial project

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Drat! I’ve gotten the information about the first Frankenstein dare (a short story challenge) a little late in the game since the deadline is 11:59 pm PDT on July 31, 2016. In any event, here’s more about the two dares,

And for those who like their information in written form, here are the details from the Arizona State University’s (ASU) Frankenstein Bicentennial Dare (on The Franklin Bicentennial Project website),

Two centuries ago, on a dare to tell the best scary story, 19-year-old Mary Shelley imagined an idea that became the basis for Frankenstein. Mary’s original concept became the novel that arguably kick-started the genres of science fiction and Gothic horror, but also provided an enduring myth that shapes how we grapple with creativity, science, technology, and their consequences.
Two hundred years later, inspired by that classic dare, we’re challenging you to create new myths for the 21st century along with our partners National Novel Writing Month (NaNoWriMo), Chabot Space and Science Center, and Creative Nonfiction magazine.

FRANKENSTEIN 200

Presented by NaNoWriMo and the Chabot Space and Science Center

Frankenstein is a classic of Gothic literature – a gripping, tragic story about Victor Frankenstein’s failure to accept responsibility for the consequences of bringing new life into the world. In this dare, we’re challenging you to write a scary story that explores the relationship between creators and the “monsters” they create.

Almost anything that we create can become monstrous: a misinterpreted piece of architecture; a song whose meaning has been misappropriated; a big, but misunderstood idea; or, of course, an actual creature. And in Frankenstein, Shelley teaches us that monstrous does not always mean evil – in fact, creators can prove to be more destructive and inhuman than the things they bring into being

Tell us your story in 1,000 – 1,800 words on Medium.com and use the hashtag #Frankenstein200. Read other #Frankenstein200 stories, and use the recommend button at the bottom of each post for the stories you like. Winners in the short fiction contest will receive personal feedback from Hugo and Sturgeon Award-winning science fiction and fantasy author Elizabeth Bear, as well as a curated selection of classic and contemporary science fiction books and  Frankenstein goodies, courtesy of the NaNoWriMo team.

Rules and Mechanics

  • There are no restrictions on content. Entry is limited to one submission per author. Submissions must be in English and between 1,000 to 1,800 words. You must follow all Medium Terms of Service, including the Rules.
  • All entries submitted and tagged as #Frankenstein200 and in compliance with the rules outlined here will be considered.
  • The deadline for submissions is 11:59 PM on July 31, 2016.
  • Three winners will be selected at random on August 1, 2016.
  • Each winner receives the following prize package including:
  • Additionally, one of the three winners, chosen at random, will receive written coaching/feedback from Elizabeth Bear on his or her entry.
  • Select stories will be featured on Frankenscape, a public geo-storytelling project hosted by ASU’s Frankenstein Bicentennial Project. Stories may also be featured in National Novel Writing Month communications and social media platforms.
  • U.S. residents only [emphasis mine]; void where prohibited by law. No purchase is necessary to enter or win.

Dangerous Creations: Real-life Frankenstein Stories

Presented by Creative Nonfiction magazine

Creative Nonfiction magazine is daring writers to write original and true stories that explore humans’ efforts to control and redirect nature, the evolving relationships between humanity and science/technology, and contemporary interpretations of monstrosity.

Essays must be vivid and dramatic; they should combine a strong and compelling narrative with an informative or reflective element and reach beyond a strictly personal experience for some universal or deeper meaning. We’re open to a broad range of interpretations of the “Frankenstein” theme, with the understanding that all works submitted must tell true stories and be factually accurate. Above all, we’re looking for well-written prose, rich with detail and a distinctive voice.

Creative Nonfiction editors and a judge (to be announced) will award $10,000 and publication for Best Essay and two $2,500 prizes and publication for runners-up. All essays submitted will be considered for publication in the winter 2018 issue of the magazine.

Deadline for submissions: March 20, 2017.
For complete guidelines: www.creativenonfiction.org/submissions

[Note: There is a submission fee for the nonfiction dare and no indication as to whether or not there are residency requirements.]

A July 27, 2016 email received from The Frankenstein Bicentennial Project (which is how I learned about the dares somewhat belatedly) has this about the first dare,

Planetary Design, Transhumanism, and Pork Products
Our #Frankenstein200 Contest Took Us in Some Unexpected Directions

Last month [June 2016], we partnered with National Novel Writing Month (NaNoWriMo) and The Chabot Space and Science Center to dare the world to create stories in the spirit of Mary Shelley’s Frankenstein, to celebrate the 200th anniversary of the novel’s conception.

We received a bevy of intriguing and sometimes frightening submissions that explore the complex relationships between creators and their “monsters.” Here are a few tales that caught our eye:

The Man Who Harnessed the Sun
By Sandra Knisely
Eliza has to choose between protecting the scientist who once gave her the world and punishing him for letting it all slip away. Read the story…

The Mortality Complex
By Brandon Miller
When the boogeyman of medical students reflects on life. Read the story…

Bacon Man
By Corey Pressman
A Frankenstein story in celebration of ASU’s Frankenstein Bicentennial Project. And bacon. Read the story… 

You can find the stories that have been submitted to date for the creative short story dare at Medium.com.

Good luck! And, don’t forget to tag your short story with #Frankenstein200 and submit it by July 31, 2016 (if you are a US resident). There’s still lots of time to enter a submission for a creative nonfiction piece.

A method for producing two-dimensional quasicrystals from metal organic networks

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A July 13, 2016 news item on ScienceDaily highlights an advance where quasicrystals are concerned,

Unlike classical crystals, quasicrystals do not comprise periodic units, even though they do have a superordinate structure. The formation of the fascinating mosaics that they produce is barely understood. In the context of an international collaborative effort, researchers at the Technical University of Munich (TUM) have now presented a methodology that allows the production of two-dimensional quasicrystals from metal-organic networks, opening the door to the development of promising new materials.

A July 13, 2016 TUM press release (also on EurekAlert), which originated the news item, explains further,

Physicist Daniel Shechtman [emphasis mine] merely put down three question marks in his laboratory journal, when he saw the results of his latest experiment one day in 1982. He was looking at a crystalline pattern that was considered impossible at the time. According to the canonical tenet of the day, crystals always had so-called translational symmetry. They comprise a single basic unit, the so-called elemental cell, that is repeated in the exact same form in all spatial directions.

Although Shechtman’s pattern did contain global symmetry, the individual building blocks could not be mapped onto each other merely by translation. The first quasicrystal had been discovered. In spite of partially stark criticism by reputable colleagues, Shechtman stood fast by his new concept and thus revolutionized the scientific understanding of crystals and solid bodies. In 2011 he ultimately received the Nobel Prize in Chemistry. To this day, both the basic conditions and mechanisms by which these fascinating structures are formed remain largely shrouded in mystery.

A toolbox for quasicrystals

Now a group of scientists led by Wilhelm Auwärter and Johannes Barth, both professors in the Department of Surface Physics at TU Munich, in collaboration with Hong Kong University of Science and Technology (HKUST, Prof. Nian Lin, et al) and the Spanish research institute IMDEA Nanoscience (Dr. David Écija), have developed a new basis for producing two-dimensional quasicrystals, which might bring them a good deal closer to understanding these peculiar patterns.

The TUM doctoral candidate José Ignacio Urgel made the pioneering measurements in the course of a research fellowship at HKUST. “We now have a new set of building blocks that we can use to assemble many different new quasicrystalline structures. This diversity allows us to investigate on how quasicrystals are formed,” explain the TUM physicists.

The researchers were successful in linking europium – a metal atom in the lanthanide series – with organic compounds, thereby constructing a two-dimensional quasicrystal that even has the potential to be extended into a three-dimensional quasicrystal. To date, scientists have managed to produce many periodic and in part highly complex structures from metal-organic networks, but never a quasicrystal.

The researchers were also able to thoroughly elucidate the new network geometry in unparalleled resolution using a scanning tunnelling microscope. They found a mosaic of four different basic elements comprising triangles and rectangles distributed irregularly on a substrate. Some of these basic elements assembled themselves to regular dodecagons that, however, cannot be mapped onto each other through parallel translation. The result is a complex pattern, a small work of art at the atomic level with dodecagonal symmetry.

Interesting optical and magnetic properties

In their future work, the researchers are planning to vary the interactions between the metal centers and the attached compounds using computer simulation and experiments in order to understand the conditions under which two-dimensional quasicrystals form. This insight could facilitate the future development of new tailored quasicrystalline layers.

These kinds of materials hold great promise. After all, the new metal-organic quasicrystalline networks may have properties that make them interesting in a wide variety of application. “We have discovered a new playing field on which we can not only investigate quasicrystallinity, but also create new functionalities, especially in the fields of optics and magnetism,” says Dr. David Écija of IMDEA Nanoscience.

For one, scientists could one day use the new methodology to create quasicrystalline coatings that influence photons in such a manner that they are transmitted better or that only certain wavelengths can pass through the material.

In addition, the interactions of the lanthanide building blocks in the new quasicrystals could facilitate the development of magnetic systems with very special properties, so-called “frustrated systems”. Here, the individual atoms in a crystalline grid interfere with each other in a manner that prevents grid points from achieving a minimal energy state. The result: exotic magnetic ground states that can be investigated as information stores for future quantum computers.

The researchers have made an image available,

The quasicrystalline network built up with europium atoms linked with para-quaterphenyl–dicarbonitrile on a gold surface (yellow) - Image: Carlos A. Palma / TUM

The quasicrystalline network built up with europium atoms linked with para-quaterphenyl–dicarbonitrile on a gold surface (yellow) – Image: Carlos A. Palma / TUM

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

Quasicrystallinity expressed in two-dimensional coordination networks by José I. Urgel, David Écija, Guoqing Lyu, Ran Zhang, Carlos-Andres Palma, Willi Auwärter, Nian Lin, & Johannes V. Barth. Nature Chemistry 8, 657–662 (2016) doi:10.1038/nchem.2507 Published online 16 May 2016

This paper is behind a paywall.

For anyone interested in more about the Daniel Schechter story and how he was reviled for his discovery of quasicrystals, there’s more in my Dec. 24, 2013 posting (scroll down about 60% of the way).

European Commission (EC) responds to a 2014 petition calling for a European Union (EU)-wide ban on microplastics and nanoparticles

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Lynn Bergeson’s July 12, 2016 posting on Nanotechnology Now features information about the European Commission’s response to a petition to ban the use of microplastics and nanoparticles throughout the European Union,

On June 29, 2016, the European Commission (EC) provided a notice to the European Parliament regarding its response to a 2014 petition calling for a European Union (EU)-wide ban on microplastics and nanoparticles. … In its response, the EC states that nanoparticles “are ubiquitous in the environment,” and while some manufactured nanomaterials may potentially be carcinogenic, others are not. The EC states that the general regulatory framework on chemicals, along with the sectoral legislation, “are appropriate to assess and manage the risks from nanomaterials, provided that a case-by-case assessment is performed.” The EC notes that the need to modify the Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulation to include more specific requirements for nanomaterials was identified. According to the EC, a final impact assessment of the proposed changes is being prepared, and the modification of technical REACH Annexes to include specific considerations for nanomaterials is planned for early 2017. The EC states that it created a web portal intended to improve communication regarding nanomaterials, and that this web portal will soon be superseded by the EU Nano Observatory, which will be managed by the European Chemicals Agency (ECHA).

I was imagining the petition was made by a consortium of civil society groups but it seems it was initiated by an individual, Ludwig Bühlmeier. You can find the notice of the petition here and the petition itself (PDF) here. I believe the still current EC portal “… intended to improve communication regarding nanomaterials …” is the JRC (Joint Research Centre) Web Platform on Nanomaterials.

Connecting chaos and entanglement

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Researchers seem to have stumbled across a link between classical and quantum physics. A July 12, 2016 University of California at Santa Barbara (UCSB) news release (also on EurekAlert) by Sonia Fernandez provides a description of both classical and quantum physics, as well as, the research that connects the two,

Using a small quantum system consisting of three superconducting qubits, researchers at UC Santa Barbara and Google have uncovered a link between aspects of classical and quantum physics thought to be unrelated: classical chaos and quantum entanglement. Their findings suggest that it would be possible to use controllable quantum systems to investigate certain fundamental aspects of nature.

“It’s kind of surprising because chaos is this totally classical concept — there’s no idea of chaos in a quantum system,” Charles Neill, a researcher in the UCSB Department of Physics and lead author of a paper that appears in Nature Physics. “Similarly, there’s no concept of entanglement within classical systems. And yet it turns out that chaos and entanglement are really very strongly and clearly related.”

Initiated in the 15th century, classical physics generally examines and describes systems larger than atoms and molecules. It consists of hundreds of years’ worth of study including Newton’s laws of motion, electrodynamics, relativity, thermodynamics as well as chaos theory — the field that studies the behavior of highly sensitive and unpredictable systems. One classic example of chaos theory is the weather, in which a relatively small change in one part of the system is enough to foil predictions — and vacation plans — anywhere on the globe.

At smaller size and length scales in nature, however, such as those involving atoms and photons and their behaviors, classical physics falls short. In the early 20th century quantum physics emerged, with its seemingly counterintuitive and sometimes controversial science, including the notions of superposition (the theory that a particle can be located in several places at once) and entanglement (particles that are deeply linked behave as such despite physical distance from one another).

And so began the continuing search for connections between the two fields.

All systems are fundamentally quantum systems, according [to] Neill, but the means of describing in a quantum sense the chaotic behavior of, say, air molecules in an evacuated room, remains limited.

Imagine taking a balloon full of air molecules, somehow tagging them so you could see them and then releasing them into a room with no air molecules, noted co-author and UCSB/Google researcher Pedram Roushan. One possible outcome is that the air molecules remain clumped together in a little cloud following the same trajectory around the room. And yet, he continued, as we can probably intuit, the molecules will more likely take off in a variety of velocities and directions, bouncing off walls and interacting with each other, resting after the room is sufficiently saturated with them.

“The underlying physics is chaos, essentially,” he said. The molecules coming to rest — at least on the macroscopic level — is the result of thermalization, or of reaching equilibrium after they have achieved uniform saturation within the system. But in the infinitesimal world of quantum physics, there is still little to describe that behavior. The mathematics of quantum mechanics, Roushan said, do not allow for the chaos described by Newtonian laws of motion.

To investigate, the researchers devised an experiment using three quantum bits, the basic computational units of the quantum computer. Unlike classical computer bits, which utilize a binary system of two possible states (e.g., zero/one), a qubit can also use a superposition of both states (zero and one) as a single state. Additionally, multiple qubits can entangle, or link so closely that their measurements will automatically correlate. By manipulating these qubits with electronic pulses, Neill caused them to interact, rotate and evolve in the quantum analog of a highly sensitive classical system.

The result is a map of entanglement entropy of a qubit that, over time, comes to strongly resemble that of classical dynamics — the regions of entanglement in the quantum map resemble the regions of chaos on the classical map. The islands of low entanglement in the quantum map are located in the places of low chaos on the classical map.

“There’s a very clear connection between entanglement and chaos in these two pictures,” said Neill. “And, it turns out that thermalization is the thing that connects chaos and entanglement. It turns out that they are actually the driving forces behind thermalization.

“What we realize is that in almost any quantum system, including on quantum computers, if you just let it evolve and you start to study what happens as a function of time, it’s going to thermalize,” added Neill, referring to the quantum-level equilibration. “And this really ties together the intuition between classical thermalization and chaos and how it occurs in quantum systems that entangle.”

The study’s findings have fundamental implications for quantum computing. At the level of three qubits, the computation is relatively simple, said Roushan, but as researchers push to build increasingly sophisticated and powerful quantum computers that incorporate more qubits to study highly complex problems that are beyond the ability of classical computing — such as those in the realms of machine learning, artificial intelligence, fluid dynamics or chemistry — a quantum processor optimized for such calculations will be a very powerful tool.

“It means we can study things that are completely impossible to study right now, once we get to bigger systems,” said Neill.

Experimental link between quantum entanglement (left) and classical chaos (right) found using a small quantum computer. Photo Credit: Courtesy Image (Courtesy: UCSB)

Experimental link between quantum entanglement (left) and classical chaos (right) found using a small quantum computer. Photo Credit: Courtesy Image (Courtesy: UCSB)

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

Ergodic dynamics and thermalization in an isolated quantum system by C. Neill, P. Roushan, M. Fang, Y. Chen, M. Kolodrubetz, Z. Chen, A. Megrant, R. Barends, B. Campbell, B. Chiaro, A. Dunsworth, E. Jeffrey, J. Kelly, J. Mutus, P. J. J. O’Malley, C. Quintana, D. Sank, A. Vainsencher, J. Wenner, T. C. White, A. Polkovnikov, & J. M. Martinis. Nature Physics (2016)  doi:10.1038/nphys3830 Published online 11 July 2016

This paper is behind a paywall.