Tag Archives: Germany

What do nanocrystals have in common with the earth’s crust?

The deformation properties of nanocrystals resemble those in the earth’s crust according to a Nov. 17, 2015 news item on Nanowerk,

Apparently, size doesn’t always matter. An extensive study by an interdisciplinary research group suggests that the deformation properties of nanocrystals are not much different from those of the Earth’s crust.

“When solid materials such as nanocrystals, bulk metallic glasses, rocks, or granular materials are slowly deformed by compression or shear, they slip intermittently with slip-avalanches similar to earthquakes,” explained Karin Dahmen, a professor of physics at the University of Illinois at Urbana-Champaign. “Typically these systems are studied separately. But we found that the scaling behavior of their slip statistics agree across a surprisingly wide range of different length scales and material structures.”

There’s an illustration accompanying the research,

Courtesy of the University of Illinois

Caption: When solid materials such as nanocrystals, bulk metallic glasses, rocks, or granular materials are slowly deformed by compression or shear, they slip intermittently with slip-avalanches similar to earthquakes. Credit: University of Illinois

A Nov. 17, 2015 University of Illinois news release (also on EurekAlert) by Rick Kubetz, which originated the news item, provides more detail,

“Identifying agreement in aspects of the slip statistics is important, because it enables us to transfer results from one scale to another, from one material to another, from one stress to another, or from one strain rate to another,” stated Shivesh Pathak, a physics undergraduate at Illinois, and a co-author of the paper, “Universal Quake Statistics: From Compressed Nanocrystals to Earthquakes,” appearing in Scientific Reports. “The study shows how to identify and explain commonalities in the deformation mechanisms of different materials on different scales.

“The results provide new tools and methods to use the slip statistics to predict future materials deformation,” added Michael LeBlanc, a physics graduate student and co-author of the paper. “They also clarify which system parameters significantly affect the deformation behavior on long length scales. We expect the results to be useful for applications in materials testing, failure prediction, and hazard prevention.”

Researchers representing a broad a range of disciplines–including physics, geosciences, mechanical engineering, chemical engineering, and materials science–from the United States, Germany, and the Netherlands contributed to the study, comparing five different experimental systems, on several different scales, with model predictions.

As a solid is sheared, each weak spot is stuck until the local shear stress exceeds a random failure threshold. It then slips by a random amount until it re-sticks. The released stress is redistributed to all other weak spots. Thus, a slipping weak spot can trigger other spots to fail in a slip avalanche.

Using tools from the theory of phase transitions, such as the renormalization group, one can show that the slip statistics of the model do not depend on the details of the system.

“Although these systems span 13 decades in length scale, they all show the same scaling behavior for their slip size distributions and other statistical properties,” stated Pathak. “Their size distributions follow the same simple (power law) function, multiplied with the same exponential cutoff.”

The cutoff, which is the largest slip or earthquake size, grows with applied force for materials spanning length scales from nanometers to kilometers. The dependence of the size of the largest slip or quake on stress reflects “tuned critical” behavior, rather than so-called self-organized criticality, which would imply stress-independence.

“The agreement of the scaling properties of the slip statistics across scales does not imply the predictability of individual slips or earthquakes,” LeBlanc said. “Rather, it implies that we can predict the scaling behavior of average properties of the slip statistics and the probability of slips of a certain size, including their dependence on stress and strain-rate.”

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

Universal Quake Statistics: From Compressed Nanocrystals to Earthquakes by Jonathan T. Uhl, Shivesh Pathak, Danijel Schorlemmer, Xin Liu, Ryan Swindeman, Braden A. W. Brinkman, Michael LeBlanc, Georgios Tsekenis, Nir Friedman, Robert Behringer, Dmitry Denisov, Peter Schall, Xiaojun Gu, Wendelin J. Wright, Todd Hufnagel, Andrew Jennings, Julia R. Greer, P. K. Liaw, Thorsten Becker, Georg Dresen, & Karin A. Dahmen.  Scientific Reports 5, Article number: 16493 (2015)  doi:10.1038/srep16493 Published online: 17 November 2015

This is an open access paper.

One final comment, this story reminds me of a few other pieces of research featured here, which focus on repeating patterns in nature. The research was mentioned in an Aug. 27, 2015 posting about white dwarf stars and heartbeats and in an April 14, 2015 posting about gold nanoparticles and their resemblance to the Milky Way. You can also find more in the Wikipedia entry titled ‘Patterns in nature‘.

Nano and Japan and South Korea

It’s not always easy to get perspective about nanotechnology research and commercialization efforts in Japan and South Korea. So, it was good to see Marjo Johne’s Nov. 9, 2015 article for the Globe and Mail,

Nanotechnology, a subfield in advanced manufacturing [?] that produces technologies less than 100 nanometres in size (a human hair is about 800 times wider), is a burgeoning industry that’s projected to grow to about $135-billion in Japan by 2020. South Korea’s government said it is aiming to boost its share of the sector to 20 per cent of the global market in 2020.

“Japan and Korea are active markets for nanotechnology,” says Mark Foley, a consultant with NanoGlobe Pte. Ltd., a Singapore-based firm that helps nanotech companies bring their products to market. “Japan is especially strong on the research side and [South] Korea is very fast in plugging nanotechnology into applications.”

Andrej Zagar, author of a research paper on nanotechnology in Japan, points to maturing areas in Japan’s nanotechnology sector: applications such as nano electronics, coatings, power electronic, and nano-micro electromechanical systems for sensors. “Japan’s IT sector is making the most progress as the implementations here are made most quickly,” says Mr. Zagar, who works as business development manager at LECIP Holdings Corp., a Tokyo-based company that manufactures intelligent transport systems for global markets. “As Japan is very environmentally focused, the environment sector in nanotech – fuel-cell materials, lithium-ion nanomaterials – is worth focusing on.”

A very interesting article, although don’t take everything as gospel. The definition of nanotechnology as a subfield in advanced manufacturing is problematic to me since nanotechnology has medical and agricultural applications, which wouldn’t typically be described as part of an advanced manufacturing subfield. As well, I’m not sure where biomimicry would fit into this advanced manufacturing scheme. In any event, the applications mentioned in the article do fit that definition; its just not a comprehensive one.

Anyone who’s read this blog for a while knows I’m not a big fan of patents or the practice of using filed patents as a measure of scientific progress but in the absence of of a viable alternative, there’s this from Johne’s article,

Patent statistics suggest accelerated rates of nanotech-related innovations in these countries. According to StatNano, a website that monitors nanotechnology developments in the world, Japan and South Korea have the second and third highest number of nanotechnology patents filed this year with the United States Patent and Trademark Office.

As of September, Japan had filed close to 3,283 patents while South Korea’s total was 1,845. While these numbers are but a fraction of the United States’ 13,759 nanotech patents filed so far this year, they top Germany, which has only 1,100 USPTO nanotech patent filings this year, and Canada, which ranks 10th worldwide with 375 filings.

In South Korea, the rise of nanotechnology can be traced back to 2001, when the South Korean government launched its nanotechnology development plan, along with $94-million in funding. Since then, South Korea has poured more money into nanotechnology. As of 2012, it had invested close to $2-billion in nanotech research and development.

The applications mentioned in the article are the focus of competition not only in Japan and South Korea but internationally,

Mr. Foley says nanofibres and smart clothing are particularly hot areas in Japan these days. Nanofibers have broad applications and can be used in water and air filtration systems. He points to Toray Industries Inc. and Teijin Ltd. as leaders in advanced fibre technology.

“We’ve also seen advances in smart clothing in the last year or two, with clothing that can conduct electricity and measure things like heart rate, body temperature and sweat,” he says. “Last year, a sporting company in Japan released smart clothing based on Toray technology.”

How did Foley determine that ‘smart clothing’ is a particularly hot area in Japan? Is it the number of patents filed? Is it the amount of product in the marketplace? Is it consumer demand? And, how do those numbers compare with other countries? Also, I would have liked a little more detail as to what Foley meant by ‘nanofibres’.

This is a very Asia-centric story, which is a welcome change from US-centric and European-centric stories on this topic, and inevitably, China is mentioned,

As the nanotechnology industry continues to gain traction on a global scale, Mr. Foley says Japan and South Korea may have a hard time holding on to their top spots in the international market; China is moving up fast from behind.

“Top Chinese researchers from Harvard and Cambridge are returning to China, where in Suzhou City they’ve built a nanocity with over 200 nanotechnology-related companies,” he says …

The ‘nano city’ Foley mentions is called Nanopolis or Nanopolis Suzhou. It’s been mentioned here twice, first in a Jan. 20, 2014 posting and again in a Sept. 26, 2014 posting. It’s a massive project and I gather that while some buildings are occupied there are still a significant percentage under construction.

‘Nano to go’, a practical guide to safe handling of nanomaterials and other innovative materials in the workplace

If you’ve been looking for a practical guide to handling nanomaterials you may find that nanoToGo fills the bill. From an Oct. 23, 2015 posting by Lynn Bergeson for Nanotechnology Now,

In September 2015, “Nano to go!” was published. See http://nanovalid.eu/index.php/nanovalid-publications/306-nanotogo “Nano to go!” is “a practically oriented guidance on safe handling of nanomaterials and other innovative materials at the workplace.” The German Federal Institute for Occupational Health (BAuA) developed it within the NanoValid project.

From the nanoToGo webpage on the NanoValid project website (Note: Links have been removed),

Nano to go! contains a brochure, field studies, presentations and general documents to comprehensively support risk assessment and risk management. …

Brochure →

The brochure Safe handling of nanomaterials and other advanced materials at workplacessupports risk assessment and risk management when working with nanomaterials. It provides safety strategies and protection measures for handling nanomaterials bound in solid matrices, dissolved in liquids, insoluble or insoluble powder form, and for handling nanofibres. Additional recommendations are given for storage and disposal of nanomaterials, for protection from fire and explosion, for training and instruction courses, and for occupational health.

Field Studies→

The field studies comprise practical examples of expert assessment of safety and health at different workplaces. They contain detailed descriptions of several exposure measurements at pilot plants and laboratories. The reports describe methods, sampling strategies and devices, summarise and discuss results, and combine measurements and non-measurement methods.

General →

Useful information, templates and examples, such as operating instructions, a sampling protocol, a dialogue guide and a short introduction to safety management and nanomaterials.

Presentations →

Ready to use presentations for university lecturers, supervisors and instruction courses, complemented with explanatory notes.

The ‘brochure’ is 56 pages; I would have called it a manual.

As for the NanoValid project, there’s this from the project’s homepage,

The EU FP7 [Framework Programme 7] large-scale integrating project NanoValid (contract: 263147) has been launched on the 1st of November 2011, as one of the “flagship” nanosafety projects. The project consists of 24 European partners from 14 different countries and 6 partners from Brazil, Canada, India and the US and will run from 2011 to 2015, with a total budget of more than 13 mio EUR (EC contribution 9.6 mio EUR). Main objective of NanoValid is to develop a set of reliable reference methods and materials for the fabrication, physicochemical (pc) characterization, hazard identification and exposure assessment of engineered nanomaterials (EN), including methods for dispersion control and labelling of ENs. Based on newly established reference methods, current approaches and strategies for risk and life cycle assessment will be improved, modified and further developed, and their feasibility assessed by means of practical case studies.

I was not expecting to see Canada in there.

Upcoming PoetryFilm appearances and events

It’s been a while since I last (in a March 17, 2015 post) featured PoetryFilm. Here’s the latest from the organization’s Oct. 2015 newsletter,

  • I have been invited to join the International Jury for the CYCLOP International Videopoetry Festival, 20-22 November 2015 (Kiev, Ukraine)
  • PoetryFilm Paradox events, featuring poetry films about love, as part of the BFI LOVE season, 6 and 22 December 2015 (London, UK)
  • PoetryFilm screening + Zata Banks in conversation with filmmaker Roxana Vilk at The Scottish Poetry Library, 3 December 2015 (Scotland, UK)
  • I have been invited to judge the Carbon Culture Review poetry film competition (USA)
  • poetryfilmkanal in Germany recently invited me to write an article about the poetry film artform – it can be read here

FYI, the “I” in the announcement’s text is for Zata Banks, the founder and director of PoetryFilm since 2002.

There’s more about the CYCLOP International Videopoetry Festival in a Sept. 13, 2015 posting on the PoetryFilm website,

*The 5th CYCLOP International Videopoetry Festival will take place on 20 – 22 November 2015 in Ukraine (Kyiv). The festival programme features video poetry-related lectures, workshops, round tables, discussions, presentations of international contests and festivals, as well as a demonstration of the best examples of Ukrainian and world videopoetry, a competitive programme, an awards ceremony and other related projects.

One of the projects is a new Contest for International poetry films within the framework of the CYCLOP festival. The International Jury: Alastair Cook (Filmpoem Festival, Edinburgh, Scotland), Zata Banks (PoetryFilm, London, United Kingdom), Javier Robledo (VideoBardo, Buenos Aires, Argentina), John Bennet (videopoet, USA),  Alice Lyons (Videopoet, Sligo, Ireland), Sigrun Hoellrigl (Art Visuals & Poetry, Vienna, Austria), Lucy English (Liberated Words, Bristol, United Kingdom), Tom Konyves (poet, video producer, educator and a pioneer in the field of videopoetry, British Columbia, Canada), Polina Horodyska (CYCLOP Videopoetry Festival, Kyiv, Ukraine) and Thomas Zandegiacomo (ZEBRA Poetry Film Festival, Berlin, Germany).

*Copy taken from the CYCLOP website

You can find the CYCLOP website here but you will need Ukrainian language reading skills.

I can’t find a website for the Carbon Culture Review poetry film competition or a webpage for it on the Carbon Culture Review website but  here’s what they have to say about themselves on the journal’s About page,

Carbon Culture Review is a journal at the intersection of new literature, art, technology and contemporary culture. We define culture broadly as the values, attitudes, actions and inventions of our global society and its subcultures in our modern age. Carbon Culture Review is distributed in the United States and countries throughout the world by Publisher’s Distribution Group, Inc. and Annas International as well as digitally through 0s&1s, Magzter and Amazon. CCR is a member of Councils of Literary Magazines and Presses and also publishes monthly online issues.

The last item from the announcement that I’m highlighting is Zata’s essay for poetryfilmkanal ,

Poetry films offer creative opportunities for exploring new semiotic modes and for communicating messages and meanings in innovative ways. Poetry films open up new methods of engagement, new audiences, and new means of self-expression, and also provide rich potential for the creation, perception and experience of emotion and meaning.

We are surrounded by communicative signs in literature, art, culture and in the world at large. Whilst words represent one system of communicating, there are many other ways of making meanings, for instance, colour semiotics, typographic design, and haptic, olfactive, gustatory and durational experiences – indeed, a comprehensive list could be infinite. The uses of spoken and written words to communicate represent just two approaches among many. Through using meaning-making systems other than words, by communicating without words, or by not using words alone, we can bypass these direct signifiers and tap directly into pools of meaning, or the signifieds, associated with those words. Different combinations of systems, or modes, can reinforce each other, render meanings more complex and subtle, or contrast with each other to illuminate different perspectives. Powerful juxtapositions, associations and new meanings can therefore emerge.

The essay is a good introduction for beginners and a good refresher for those in need. Btw, I understand Zata got married in March 2015. Congratulations to Zata and Joe!

A nanoscale bacteria power grid

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.

Memristor shakeup

New discoveries suggest that memristors do not function as was previously theorized. (For anyone who wants a memristor description, there’s this Wikipedia entry.) From an Oct. 13, 2015 posting by Alexander Hellemans for the Nanoclast blog (on the IEEE [Institute for Electrical and Electronics Engineers]), Note: Links have been removed,

What’s going to replace flash? The R&D arms of several companies including Hewlett Packard, Intel, and Samsung think the answer might be memristors (also called resistive RAM, ReRAM, or RRAM). These devices have a chance at unseating the non-volatile memory champion because, they use little energy, are very fast, and retain data without requiring power. However, new research indicates that they don’t work in quite the way we thought they do.

The fundamental mechanism at the heart of how a memristor works is something called an “imperfect point contact,” which was predicted in 1971, long before anybody had built working devices. When voltage is applied to a memristor cell, it reduces the resistance across the device. This change in resistance can be read out by applying another, smaller voltage. By inverting the voltage, the resistance of the device is returned to its initial value, that is, the stored information is erased.

Over the last decade researchers have produced two commercially promising types of memristors: electrochemical metallization memory (ECM) cells, and valence change mechanism memory (VCM) cells.

Now international research teams lead by Ilia Valov at the Peter Grünberg Institute in Jülich, Germany, report in Nature Nanotechnology and Advanced Materials that they have identified new processes that erase many of the differences between EMC and VCM cells.

Valov and coworkers in Germany, Japan, Korea, Greece, and the United States started investigating memristors that had a tantalum oxide electrolyte and an active tantalum electrode. “Our studies show that these two types of switching mechanisms in fact can be bridged, and we don’t have a purely oxygen type of switching as was believed, but that also positive [metal] ions, originating from the active electrode, are mobile,” explains Valov.

Here are links to and citations for both papers,

Graphene-Modified Interface Controls Transition from VCM to ECM Switching Modes in Ta/TaOx Based Memristive Devices by Michael Lübben, Panagiotis Karakolis, Vassilios Ioannou-Sougleridis, Pascal Normand, Pangiotis Dimitrakis, & Ilia Valov. Advanced Materials DOI: 10.1002/adma.201502574 First published: 10 September 2015

Nanoscale cation motion in TaOx, HfOx and TiOx memristive systems by Anja Wedig, Michael Luebben, Deok-Yong Cho, Marco Moors, Katharina Skaja, Vikas Rana, Tsuyoshi Hasegawa, Kiran K. Adepalli, Bilge Yildiz, Rainer Waser, & Ilia Valov. Nature Nanotechnology (2015) doi:10.1038/nnano.2015.221 Published online 28 September 2015

Both papers are behind paywalls.

Quantum teleportation

It’s been two years (my Aug. 16, 2013 posting features a German-Japanese collaboration) since the last quantum teleportation posting here. First, a little visual stimulation,

Captain James T Kirk (credit: http://www.comicvine.com/james-t-kirk/4005-20078/)

Captain James T Kirk (credit: http://www.comicvine.com/james-t-kirk/4005-20078/)

Captain Kirk, also known as William Shatner, is from Montréal, Canada and that’s not the only Canadian connection to this story which is really about some research at York University (UK). From an Oct. 1, 2015 news item on Nanotechnology Now,

Mention the word ‘teleportation’ and for many people it conjures up “Beam me up, Scottie” images of Captain James T Kirk.

But in the last two decades quantum teleportation – transferring the quantum structure of an object from one place to another without physical transmission — has moved from the realms of Star Trek fantasy to tangible reality.

A Sept. 30, 2015 York University (UK) press release, which originated the news item, describes the quantum teleportation research problem and solution,

Quantum teleportation is an important building block for quantum computing, quantum communication and quantum network and, eventually, a quantum Internet. While theoretical proposals for a quantum Internet already exist, the problem for scientists is that there is still debate over which of various technologies provides the most efficient and reliable teleportation system. This is the dilemma which an international team of researchers, led by Dr Stefano Pirandola of the Department of Computer Science at the University of York, set out to resolve.

In a paper published in Nature Photonics, the team, which included scientists from the Freie Universität Berlin and the Universities of Tokyo and Toronto [emphasis mine], reviewed the theoretical ideas around quantum teleportation focusing on the main experimental approaches and their attendant advantages and disadvantages.

None of the technologies alone provide a perfect solution, so the scientists concluded that a hybridisation of the various protocols and underlying structures would offer the most fruitful approach.

For instance, systems using photonic qubits work over distances up to 143 kilometres, but they are probabilistic in that only 50 per cent of the information can be transported. To resolve this, such photon systems may be used in conjunction with continuous variable systems, which are 100 per cent effective but currently limited to short distances.

Most importantly, teleportation-based optical communication needs an interface with suitable matter-based quantum memories where quantum information can be stored and further processed.

Dr Pirandola, who is also a member of the York Centre for Quantum Technologies, said: “We don’t have an ideal or universal technology for quantum teleportation. The field has developed a lot but we seem to need to rely on a hybrid approach to get the best from each available technology.

“The use of quantum teleportation as a building block for a quantum network depends on its integration with quantum memories. The development of good quantum memories would allow us to build quantum repeaters, therefore extending the range of teleportation. They would also give us the ability to store and process the transmitted quantum information at local quantum computers.

“This could ultimately form the backbone of a quantum Internet. The revised hybrid architecture will likely rely on teleportation-based long-distance quantum optical communication, interfaced with solid state devices for quantum information processing.”

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

Advances in quantum teleportation by S. Pirandola, J. Eisert, C. Weedbrook, A. Furusawa, & S. L. Braunstein. Nature Photonics 9, 641–652 (2015) doi:10.1038/nphoton.2015.154 Published online 29 September 2015

This paper is behind a paywall.


Cleaning up carbon dioxide pollution in the oceans and elsewhere

I have a mini roundup of items (3) concerning nanotechnology and environmental applications with a special focus on carbon materials.

Carbon-capturing motors

First up, there’s a Sept. 23, 2015 news item on ScienceDaily which describes work with tiny carbon-capturing motors,

Machines that are much smaller than the width of a human hair could one day help clean up carbon dioxide pollution in the oceans. Nanoengineers at the University of California, San Diego have designed enzyme-functionalized micromotors that rapidly zoom around in water, remove carbon dioxide and convert it into a usable solid form.

The proof of concept study represents a promising route to mitigate the buildup of carbon dioxide, a major greenhouse gas in the environment, said researchers. …

A Sept 22, 2015 University of California at San Diego (UCSD) news release by Liezel Labios, which originated the news release, provides more details about the scientists’ hopes and the technology,

“We’re excited about the possibility of using these micromotors to combat ocean acidification and global warming,” said Virendra V. Singh, a postdoctoral scientist in Wang’s [nanoengineering professor and chair Joseph Wang] research group and a co-first author of this study.

In their experiments, nanoengineers demonstrated that the micromotors rapidly decarbonated water solutions that were saturated with carbon dioxide. Within five minutes, the micromotors removed 90 percent of the carbon dioxide from a solution of deionized water. The micromotors were just as effective in a sea water solution and removed 88 percent of the carbon dioxide in the same timeframe.

“In the future, we could potentially use these micromotors as part of a water treatment system, like a water decarbonation plant,” said Kevin Kaufmann, an undergraduate researcher in Wang’s lab and a co-author of the study.

The micromotors are essentially six-micrometer-long tubes that help rapidly convert carbon dioxide into calcium carbonate, a solid mineral found in eggshells, the shells of various marine organisms, calcium supplements and cement. The micromotors have an outer polymer surface that holds the enzyme carbonic anhydrase, which speeds up the reaction between carbon dioxide and water to form bicarbonate. Calcium chloride, which is added to the water solutions, helps convert bicarbonate to calcium carbonate.

The fast and continuous motion of the micromotors in solution makes the micromotors extremely efficient at removing carbon dioxide from water, said researchers. The team explained that the micromotors’ autonomous movement induces efficient solution mixing, leading to faster carbon dioxide conversion. To fuel the micromotors in water, researchers added hydrogen peroxide, which reacts with the inner platinum surface of the micromotors to generate a stream of oxygen gas bubbles that propel the micromotors around. When released in water solutions containing as little as two to four percent hydrogen peroxide, the micromotors reached speeds of more than 100 micrometers per second.

However, the use of hydrogen peroxide as the micromotor fuel is a drawback because it is an extra additive and requires the use of expensive platinum materials to build the micromotors. As a next step, researchers are planning to make carbon-capturing micromotors that can be propelled by water.

“If the micromotors can use the environment as fuel, they will be more scalable, environmentally friendly and less expensive,” said Kaufmann.

The researchers have provided an image which illustrates the carbon-capturing motors in action,

Nanoengineers have invented tiny tube-shaped micromotors that zoom around in water and efficiently remove carbon dioxide. The surfaces of the micromotors are functionalized with the enzyme carbonic anhydrase, which enables the motors to help rapidly convert carbon dioxide to calcium carbonate. Image credit: Laboratory for Nanobioelectronics, UC San Diego Jacobs School of Engineering.

Nanoengineers have invented tiny tube-shaped micromotors that zoom around in water and efficiently remove carbon dioxide. The surfaces of the micromotors are functionalized with the enzyme carbonic anhydrase, which enables the motors to help rapidly convert carbon dioxide to calcium carbonate. Image credit: Laboratory for Nanobioelectronics, UC San Diego Jacobs School of Engineering.

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

Micromotor-Based Biomimetic Carbon Dioxide Sequestration: Towards Mobile Microscrubbers by Murat Uygun, Virendra V. Singh, Kevin Kaufmann, Deniz A. Uygun, Severina D. S. de Oliveira, and oseph Wang. Angewandte Chemie DOI: 10.1002/ange.201505155 Article first published online: 4 SEP 2015

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This article is behind a paywall.

Carbon nanotubes for carbon dioxide capture (carbon capture)

In a Sept. 22, 2015 posting by Dexter Johnson on his Nanoclast blog (located on the IEEE [Institute for Electrical and Electronics Engineers] website) describes research where carbon nanotubes are being used for carbon capture,

Now researchers at Technische Universität Darmstadt in Germany and the Indian Institute of Technology Kanpur have found that they can tailor the gas adsorption properties of vertically aligned carbon nanotubes (VACNTs) by altering their thickness, height, and the distance between them.

“These parameters are fundamental for ‘tuning’ the hierarchical pore structure of the VACNTs,” explained Mahshid Rahimi and Deepu Babu, doctoral students at the Technische Universität Darmstadt who were the paper’s lead authors, in a press release. “This hierarchy effect is a crucial factor for getting high-adsorption capacities as well as mass transport into the nanostructure. Surprisingly, from theory and by experiment, we found that the distance between nanotubes plays a much larger role in gas adsorption than the tube diameter does.”

Dexter provides a good and brief summary of the research.

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

Double-walled carbon nanotube array for CO2 and SO2 adsorption by Mahshid Rahimi, Deepu J. Babu, Jayant K. Singh, Yong-Biao Yang, Jörg J. Schneider, and Florian Müller-Plathe. J. Chem. Phys. 143, 124701 (2015); http://dx.doi.org/10.1063/1.4929609

This paper is open access.

The market for nanotechnology-enabled environmental applications

Coincident with stumbling across these two possible capture solutions, I found this Sept. 23, 2015 BCC Research news release,

A groundswell of global support for developing nanotechnology as a pollution remediation technique will continue for the foreseeable future. BCC Research reveals in its new report that this key driver, along with increasing worldwide concerns over removing pollutants and developing alternative energy sources, will drive growth in the nanotechnology environmental applications market.

The global nanotechnology market in environmental applications is expected to reach $25.7 billion by 2015 and $41.8 billion by 2020, conforming to a five-year (2015-2020) compound annual growth rate (CAGR) of 10.2%. Air remediation as a segment will reach $10.2 billion and $16.7 billion in 2015 and 2020, respectively, reflecting a five-year CAGR of 10.3%. Water remediation as a segment will grow at a five-year CAGR of 12.4% to reach $10.6 billion in 2020.

As nanoparticles push the limits and capabilities of technology, new and better techniques for pollution control are emerging. Presently, nanotechnology’s greatest potential lies in air pollution remediation.

“Nano filters could be applied to automobile tailpipes and factory smokestacks to separate out contaminants and prevent them from entering the atmosphere. In addition, nano sensors have been developed to sense toxic gas leaks at extremely low concentrations,” says BCC research analyst Aneesh Kumar. “Overall, there is a multitude of promising environmental applications for nanotechnology, with the main focus area on energy and water technologies.”

You can find links to the report, TOC (table of contents), and report overview on the BCC Research Nanotechnology in Environmental Applications: The Global Market report webpage.

Structural memory of water and the picosecond timescale

Water is a unique liquid and researchers from Germany and the Netherlands can detail at least part of why that’s so according to a Sept. 18, 2015 news item on Nanowerk,

A team of scientists from the Max Planck Institute for Polymer Research (MPI-P) in Mainz, Germany and FOM Institute AMOLF in the Netherlands have characterized the local structural dynamics of liquid water, i.e. how quickly water molecules change their binding state. Using innovative ultrafast vibrational spectroscopies, the researchers show why liquid water is so unique compared to other molecular liquids. …

With the help of a novel combination of ultrafast laser experiments, the scientists found that local structures persist in water for longer than a picosecond, a picosecond (ps) being one thousandth of one billionth of a second ((1012 s). This observation changes the general perception of water as a solvent.

A Sept. 18, 2015 Max Planck Institute for Polymer Research press release (also on EurekAlert), which originated the news item, details the research,

… “71% of the earth’s surface is covered with water. As most chemical and biological reactions on earth occur in water or at the air water interface in oceans or in clouds, the details of how water behaves at the molecular level are crucial. Our results show that water cannot be treated as a continuum, but that specific local structures exist and are likely very important” says Mischa Bonn, director at the MPI-P.

Water is a very special liquid with extremely fast dynamics. Water molecules wiggle and jiggle on sub-picosecond timescales, which make them undistinguishable on this timescale. While the existence of very short-lived local structures – e.g. two water molecules that are very close to one another, or are very far apart from each other – is known to occur, it was commonly believed that they lose the memory of their local structure within less than 0.1 picoseconds.

The proof for relatively long-lived local structures in liquid water was obtained by measuring the vibrations of the Oxygen-Hydrogen (O-H) bonds in water. For this purpose the team of scientists used ultrafast infrared spectroscopy, particularly focusing on water molecules that are weakly (or strongly) hydrogen-bonded to their neighboring water molecules. The scientists found that the vibrations live much longer (up to about 1 ps) for water molecules with a large separation, than for those that are very close (down to 0.2 ps). In other words, the weakly bound water molecules remain weakly bound for a remarkably long time.

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

Strong frequency dependence of vibrational relaxation in bulk and surface water reveals sub-picosecond structural heterogeneity by Sietse T. van der Post, Cho-Shuen Hsieh, Masanari Okuno, Yuki Nagata, Huib J. Bakker, Mischa Bonn & Johannes Hunger. Nature Communications 6, Article number: 8384 doi:10.1038/ncomms9384 Published 18 September 2015

This is an open access paper,