Monthly Archives: October 2013

Still time to vote in Argonne National Laboratory’s Art for Science contest

Argonne National Laboratory runs an annual contest, Art for Science, where employees and facility users can submit images. I don’t believe there any prizes associated with the contest other than winning the satisfaction of knowing that your image was aesthetically pleasing and an appearance in an Argonne publication and/or in a public display somewhere. This year’s contest according to an Oct. 27, 2013 news item on Nanowerk is still open for voting,

Help Argonne choose the winners of its 2013 Art of Science contest. The annual contest calls for lab employees and users of Argonne’s facilities to submit images and photographs that showcase their research. Some are computer simulations, some are photographs, and some are taken with incredibly powerful transmission electron microscopes that see down to nearly atomic level; all of them show the stunning intersection of beauty and science in Argonne’s world-class labs. Votes will be accepted through Nov. 1, 2013.

This is one of the submissions,

Lead Titanate Domain Terrain The tallest "mountains" in the landscape below are actually only a few nanometers high (about how long your fingernails have grown while reading this). It's made out of lead titanate, which has unique properties and is widely used in sensors and actuators. The image, which has color added, was created using atomic force microscopy. [Argonne National Laboratory]

Lead Titanate Domain Terrain
The tallest “mountains” in the landscape below are actually only a few nanometers high (about how long your fingernails have grown while reading this). It’s made out of lead titanate, which has unique properties and is widely used in sensors and actuators. The image, which has color added, was created using atomic force microscopy. [Argonne National Laboratory]

You can find this image along with many others in the Argonne National Laboratory 2013 Art for Science survey, Winning entries for the 2012 contest were shown in a variety of locations according to Stephanie Yin’s September 11, 2012 article, Finding a palate for the science palette, for Argonne National Laboratory (Note: Links have been removed),

Images from the contest grace the pages of Argonne publications, adorn laboratory buildings and share cutting-edge research with audiences outside the laboratory through traveling exhibits. They have appeared in public-access libraries, including the University of Chicago’s John Crerar Library and the Downers Grove Public Library.

Most recently, 27 Art of Science posters were installed in an exhibit at O’Hare International Airport in Chicago. The O’Hare exhibit, which is now up and will run through early 2013, is located in the hallways connecting Terminals 2 and 3 adjacent to the Rotunda.

Rising from the dead: the inventory of nanotechnology-based consumer products

The inventory of nanotechnology-based consumer products or the Consumer Products Inventory (CPI) is still cited in articles about nanotechnology and its pervasive use in consumer products despite the fact that the inventory was effectively rendered inactive (i.e., dead) in 2009 and that  it was a voluntary system with no oversight, meaning whoever made the submission to the inventory could make any claims they wanted. Now that it’s 2013, things are about to change according to an Oct. 28, 2013 news item on ScienceDaily,

As a resource for consumers, scientists, and policy makers, the Virginia Tech Center for Sustainable Nanotechnology (VTSuN) has joined the Woodrow Wilson International Center for Scholars to renew and expand the Nanotechnology Consumer Product Inventory, an important source of information about products using nanomaterials.

“We want people to appreciate the revolution, such as in electronics and medicine. But we also want them to be informed,” said Nina Quadros, a research scientist at Virginia Tech’s Institute for Critical Technology and Applied Science and associate director of VTSuN, who leads a team of Virginia Tech faculty members and students on this project. Todd Kuiken, senior program associate, and David Rajeski, director of the science and technology innovation program, lead this project at the Wilson Center.

The Oct. 28, 2013 Virginia Tech (Virginia Polytechnic Institute and State University) news release by Susan Trulove (which originated the news item),provides a brief history of the inventory and a description of its revivification,

The Wilson Center and the Project on Emerging Nanotechnology created the inventory in 2005. It grew from 54 to more than 1,000 products, many of which have come and gone. The inventory became the most frequently cited resource, showcasing the widespread applications of nanotechnology. However, in 2009, the project was no longer funded.

“I used it in publications and presentations when talking about all the ways nano is part of people’s lives in consumer products,” said Matthew Hull, who manages the Institute for Critical Technology and Applied Science’s investment portfolio in nanoscale science and engineering, which includes the Center for Sustainable Nanotechnology. “But the inventory was criticized by researchers, regulators, and manufacturers for the lack of scientific information available to support product claims.”

In a meeting with his friend, Andrew Maynard, director of the University of Michigan Risk Science Center, who had initiated the inventory when he was at the Wilson Center, Hull proposed leveraging Institute for Critical Technology and Applied Science and Center for Sustainable Nanotechnology resources to improve the inventory.

“My role was to ask ‘what if’ and [the Virginia Tech Center for Sustainable Nanotechnology] ran with it,” said Hull.

A partnership was formed and, with funding from the Virginia Tech institute, the Center for Sustainable Nanotechnology restructured the inventory to improve the reliability, functionality, and scientific credibility of the database.

“Specifically, we added scientific significance and usefulness by including qualitative and quantitative descriptors for the products and the nanomaterials contained in these products, such as size, concentration, and potential exposure routes,” said Quadros. For example, an intentional exposure route would be the way a medicine is administered. An unintentional exposure would be when a child chews on a toy that has been treated with silver nanoparticles that are used as an antimicrobial. The potential health effect of nanomaterials on children was Quadros doctoral research and she used the inventory to find products designed for children that use nanomaterials, such as plush toys.

“One of the best things about the new version of the inventory is the additional information and the ability to search by product type or the type of nanomaterial,” she said. “When researchers were first attempting to assess the potential environmental impacts of nanotechnology, one main challenge was understanding how these nanomaterials might end up in the environment in the first place. After searching the CPI and seeing the vast applications of nanotechnologies in consumer products it was easier to narrow down scenarios.”

For example, Quadros said many silver nanoparticles are used in clothing for antimicrobial protection, so we can infer that some silver nanoparticles may end up in wastewater treatment plants after clothes washing. This helped justify some of the research on the effects of silver nanoparticle in the biological wastewater treatment processes. Currently, the inventory lists 188 products under the ‘clothing’ category.”

This team also included published scientific data related to those products, where available, and developed a metric to assess the reliability of the data on each inventory entry.

The team interviewed more than 50 nanotechnology experts with more than 350 combined years of experience in nanotechnology, Quadros said. “Their answers provided valuable guidance to help us address diverse stakeholder needs.”

In addition, the site’s users can log in and add information based on their own expertise. “Anyone can suggest edits. The curator and reviewer will approve the edits, and then the new information will go live,” Quadros said.

“We’ve added the horsepower of [the Center for Sustainable Nanotechnology], but opened it by means of crowdsourcing to new information, such as refuting or supporting claims made about products,” Hull said.

“The goal of this work is to create a living, growing inventory for the exchange of accurate information on nano­enabled consumer products,” Quadros said. “Improved information sharing will allow citizens, manufacturers, scientists, policymakers, and others to better understand how nanotechnology is being used in the consumer marketplace,” she said.

As of October 2013,

The inventory currently lists more than 1,600 consumer products that claim to contain nanotechnology or have been found to contain nanomaterials.

Quadros will give a presentation about the inventory at the Sustainable Nanotechnology Organization conference in Santa Barbara on Nov. 3-5 and will present to the U.S. Environmental Protection Agency and the National Science Foundation in the spring.

Key collaborators at Virginia Tech are Sean McGinnis, an associate research professor in the materials science and engineering department; Linsey Marr, professor of civil and environmental engineering; her postdoc, Eric Vejerano, who was instrumental in development of product categories; and Michael Hochella, a university distinguished professor in the geosciences department and Virginia Tech Center for Sustainable Nanotechnology director.

You can find the Consumer Products Inventory here where it is still hosted by the Woodrow Wilson Center’s Project on Emerging Nanotechnologies. The website for the Second Sustainable Nanotechnology Organization Conference where Quadros will be presenting can be found here and is where this conference description can be found,

The objective of this conference is to bring together scientific experts from academia, industry, and government agencies from around the world to present and discuss current research findings on the subject of nanotechnology and sustainability.

The conference program will address the critical aspects of sustainable nanotechnology such as life cycle assessment, green synthesis, green energy, industrial partnerships, environmental and biological fate, and the overall sustainability of engineered nanomaterials. In principle, this involves the fundamental/applied research on the chemistry of producing new green nanomaterials; eco-manufacturing processing of nanomaterials and products, using nanotechnology to benefit society, and examining possible harmful effects of nanotechnology.

The conference will also foster new collaborations between academic and industrial participants. This community of users, researchers and developers of engineered nanomaterials will provide a long-term, scientific assessment of where the science is for sustainable nano, where it should be heading, and what steps academics, government agencies and others can take now to reach targeted goals. In addition, the conference will serve as the platform to initiate the formation of the Sustainable Nanotechnology Organization (SNO), a non-profit, international professional society dedicated to advancing sustainable nanotechnology through education, research, and promotion of responsible development of nanotechnology.

Finally because I can resist no longer, especially so near to Hallowe’en, I guess you could call the ‘renewed’ CPI, a zombie CPI as it’s back from the dead and it needs brains,

Zombies in Moscow, 26 April 2009 Credit: teujene [downloaded from http://en.wikipedia.org/wiki/File:Zombies_in_Moscow.jpg]

Zombies in Moscow, 26 April 2009 Credit: teujene [downloaded from http://en.wikipedia.org/wiki/File:Zombies_in_Moscow.jpg]

Recycling carbon dioxide with gold nanoparticles

Researchers at Brown University (in Providence, Rhode Island) have developed a technique using gold nanoparticles to capture carbon dioxide and turn it into carbon monoxide (from the Oct. 24, 2013 Brown University news release [also on EurekAlert]),

It’s a 21st-century alchemist’s dream: turning Earth’s superabundance of carbon dioxide — a greenhouse gas — into fuel or useful industrial chemicals. Researchers from Brown have shown that finely tuned gold nanoparticles can do the job. The key is maximizing the particles’ long edges, which are the active sites for the reaction.[This paragraph is present only on the Brown website news release]

By tuning gold nanoparticles to just the right size, researchers from Brown University have developed a catalyst that selectively converts carbon dioxide (CO2) to carbon monoxide (CO), an active carbon molecule that can be used to make alternative fuels and commodity chemicals.

“Our study shows potential of carefully designed gold nanoparticles to recycle CO2 into useful forms of carbon,” said Shouheng Sun, professor of chemistry and one of the study’s senior authors. “The work we’ve done here is preliminary, but we think there’s great potential for this technology to be scaled up for commercial applications.”

The scientists were trying to solve a major problem with recycling carbon dioxide when using gold (from the news release),

Converting CO2 to CO isn’t easy. Prior research has shown that catalysts made of gold foil are active for this conversion, but they don’t do the job efficiently. The gold tends to react both with the CO2 and with the water in which the CO2 is dissolved, creating hydrogen byproduct rather than the desired CO.

The Brown research team decided to try gold nanoparticles and had a surprising result (from the news release),

The Brown experimental group, led by Sun and Wenlei Zhu, a graduate student in Sun’s group, wanted to see if shrinking the gold down to nanoparticles might make it more selective for CO2. They found that the nanoparticles were indeed more selective, but that the exact size of those particles was important. Eight nanometer particles had the best selectivity, achieving a 90-percent rate of conversion from CO2 to CO. Other sizes the team tested — four, six, and 10 nanometers — didn’t perform nearly as well.

“At first, that result was confusing,” said Andrew Peterson, professor of engineering and also a senior author on the paper. “As we made the particles smaller we got more activity, but when we went smaller than eight nanometers, we got less activity.”

The researchers investigated further and found a relationship between size and shape which affects the gold nanoparticles’ performance (from the news release),

To understand what was happening, Peterson and postdoctoral researcher Ronald Michalsky used a modeling method called density functional theory. They were able to show that the shapes of the particles at different sizes influenced their catalytic properties.

“When you take a sphere and you reduce it to smaller and smaller sizes, you tend to get many more irregular features — flat surfaces, edges and corners,” Peterson said. “What we were able to figure out is that the most active sites for converting CO2 to CO are the edge sites, while the corner sites predominantly give the by-product, which is hydrogen. So as you shrink these particles down, you’ll hit a point where you start to optimize the activity because you have a high number of these edge sites but still a low number of these corner sites. But if you go too small, the edges start to shrink and you’re left with just corners.”

Now that they understand exactly what part of the catalyst is active, the researchers are working to further optimize the particles. “There’s still a lot of room for improvement,” Peterson said. “We’re working on new particles that maximize these active sites.”

The researchers believe these findings could be an important new avenue for recycling CO2 on a commercial scale.

“Because we’re using nanoparticles, we’re using a lot less gold than in a bulk metal catalyst,” Sun said. “That lowers the cost for making such a catalyst and gives the potential to scale up.”

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

Monodisperse Au Nanoparticles for Selective Electrocatalytic Reduction of CO2 to CO by Wenlei Zhu, Ronald Michalsky, Önder Metin, Haifeng Lv, Shaojun Guo, Christopher J. Wright, Xiaolian Sun, Andrew A. Peterson, and Shouheng Sun. J. Am. Chem. Soc., DOI: 10.1021/ja409445p Publication Date (Web): October 24, 2013
Copyright © 2013 American Chemical Society

This article is behind a paywall.

Fluid mechanics and fluid identities at Vancouver’s (Canada) Café Scientifique Oct. 29, 2013 meeting

Vancouver’s Café Scientifique is being held in the back room of the The Railway Club (2nd floor of 579 Dunsmuir St. [at Seymour St.], Vancouver, Canada), on Tuesday, October 29,  2013 at 7:30 pm. Here’s the talk description (from the Oct. 22, 2013 announcement), Café Scientifique,

Our speaker for the evening will be Prof. Bud Homsy. The title of his talk is:

Fluid mechanics – What do the Red Spot of Jupiter and the flagellar motion of e.coli have in common?

Fluid mechanics – the study of the motion of fluids when acted upon by forces – is capable of describing fluid flows on a very wide range of length and time scales, including the Red Spot (roughly three Earth diameters in size), the Earth’s weather system, locomotion of trains, planes and automobiles, and swimming of fish, sperm, and microorganisms on the smallest scale.  It is safe to say that almost every aspect of human existence depends on fluids and their flow properties.  This talk will illustrate all the flows listed above (and more!) with movies and discussion of the mathematics and physics behind their description and understanding.

I found Bud Homsy’s faculty webpage here in the University of British Columbia’s Dept. of Mathematics where he is visiting or perhaps he has a dual appointment. There’s another faculty webpage at the University of California at Santa Barbara where he’s identified as George Homsy, a professor in the Department of Mechanical and Enviromental Engineering. I think it’s the same man; he looks the same in both pictures.

Simon Fraser University scientists peer deeply into fuel cells while University of Toronto experts debate nanotechnoloy: revolution or evolution?

An Oct. 25, 2013 Simon Fraser University (SFU; Vancouver, Canada) news release touts a new centre and a very snazzy piece of equipment (Nano X-ray Computed Tomography [NXCT]) that scientists will be able to build and purchase courtesy of a new grant (Note: Links have been removed),

Powerful scanners that give scientists a direct line of sight into hydrogen fuel cells are the latest tools Simon Fraser University researchers will use to help Ballard Power Systems Inc create more durable, lower-cost fuel cells. Use of these fuel cells in vehicles can substantially reduce harmful emissions in the transportation sector.

The new Nano X-ray Computed Tomography (NXCT) tools will become part of a nationally unique fuel cell testing and characterization facility. The new four-year, $6.5 million project is receiving $3.39 million in funding from Automotive Partnership Canada (APC).

It’s one of 10 university-industry partnerships receiving a total of more than $52 million ($30 million from APC, leveraged by more than $22 million from industry and other partners) announced today by the Natural Sciences and Engineering Research Council of Canada (NSERC).

Research carried out in the new visualization facility, expected to be operational by spring, will further the ongoing research collaboration between Ballard and SFU.

“This will be an unprecedented, world-class testing facility dedicated entirely to this project over the next four years,” says principal investigator Erik Kjeang, an internationally known fuel cell expert and director of SFU’s Fuel Cell Research Laboratory (FCRel). “Beyond its capabilities, that’s a strength in itself.”

Says Ballard’s Research Manager Shanna Knights: “It’s a unique opportunity, to have dedicated access to highly specialized equipment and access to university experts who are focused on Ballard’s needs.”

Researchers will use the facility to develop and advance the technology required for the company’s next generation of fuel cell products, helping to meet its targets related to extending fuel cell life while improving efficiency.

Kjeang, an assistant professor in SFU’s School of Mechatronic Systems Engineering, says the new, sophisticated nano-scale scanning capabilities will enable researchers to see inside the fuel cell micro-structure and track how its components degrade over time. The research will play an important role in the university’s focus on advancing clean energy initiatives.

“Partnerships with leading companies such as Ballard solidify SFU’s reputation as a world-class innovator in fuel cell research,” says Nimal Rajapakse, dean and professor, Faculty of Applied Sciences. “This unique fuel cell testing facility will be used for cutting edge research and training of HQP (highly qualified personnel) that will help to strengthen the competitiveness of the Canadian automotive and clean energy industry. We are grateful that Automotive Partnership Canada has provided this second round of funding to support the SFU-Ballard research collaboration.”

Adds Kjeang: “Thanks to the APC program, and the support NSERC has provided over the years, I have been able to both explore the fundamentals of fuel cell technology and to successfully work with companies who are making globally leading advances in green automotive technology.”

A former research engineer who began his career at Ballard in 2008, Kjeang came to SFU to continue his own research interests while keeping a foot in industry. He also continues to lead a complementary project with Ballard that involves nearly 40 students and researchers working to improve the durability of heavy-duty bus fuel cells.

You can find the news release with all its links intact here.  I am a little surprised that there isn’t any mention of SFU’s 4D Labs (their nanotechnology showcase project), especially since one of the areas of interest is this (from the 4D Labs Research Areas webpage),

Cleaner Energy
New materials innvovation is critical to lower the costs and improve the performance of promising technologies such as photovoltaics, fuel cells and passive energy control sytems. [emphasis mine]

Meanwhile, experts gathered at the University of Toronto debated nanotechnology by asking this question: revolution or evolution? as  part of a celebratory event extending from Oct. 23 to Oct. 24, 2013. From a University of Toronto Oct. 23, 2013 news release (H/T Hispanic Business.com),

A panel of nanotechnology experts, moderated by U of T Materials Science & Engineering Professor Doug Perovic will explore the possibilities of the technology as part of a celebration marking the University of Toronto’s  Department of Materials Science & Engineering’s 100-year anniversary.

Nanotechnology is the science of manipulating atoms and molecules on a scale so small they can’t be seen with an ordinary microscope. It’s about coaxing them into displaying unusual properties, such as a material 10 times as strong as steel, but a fraction of its weight, or solar panels that produce fuel rather than electricity.

While nanotech has the potential to transform society in ways no one ever thought of before, it’s also been the subject of much hype.

“Some would say it has not met expectations,” says Professor Perovic, Canada’s ‘nabob of nanotechnology.’ “While it hasn’t taken off in the areas people predicted it would take off, it has become huge in unpredictable areas.”

Some of the world’s top nanotechnology experts will be part of the panel and give the big picture.

WHAT: Nanotechnology panel featuring several experts

WHERE: Room#: BA 1130, Bahen Centre for Information Technology, University of Toronto, 40 St. George Street (Google map: http://goo.gl/maps/tXBxP)

WHEN: 10am, Thursday (October 24)

WHO:
Michael F. Ashby
Royal Society Research Professor
Department of Engineering
University of Cambridge

Shawn Qu | MMS PhD 9T5
Chairman, President & CEO
Canadian Solar Inc.

Polina Snugovsky
Chief Metallurgist, Celestica Inc.
Robert B. Storey | MMS 7T7
Managing Partner, Bereskin & Parr LLP

Gino Palumbo
MMS 8T3, MASc 8T5, PhD 8T9
President & CEO, Integran Technologies Inc

Donald R. Sadoway
EngSci 7T2, MMS MASc 7T3, PhD 7T7
John F. Elliot Professor of Materials Chemistry
Department of Materials Science & Engineering, MIT

David S. Wilkinson
EngSci 7T2, MMS MASc 7T4
Vice-President & Provost, Academic
McMaster University

I wonder if the experts came to any conclusions.

Casimir and its reins: engineering nanostructures to control quantum effects

Thank you to whomever wrote this headline for the Oct. 22, 2013 US National Institute of Standards and Technology (NIST) news release, also on EurekAlert, titled: The Reins of Casimir: Engineered Nanostructures Could Offer Way to Control Quantum Effect … Once a Mystery Is Solved, for getting the word ‘reins’ correct.

I can no longer hold back my concern over the fact that there are three words that sound the same but have different meanings and one of those words is often mistakenly used in place of the other.

reins

reigns

rains

The first one, reins, refers to narrow leather straps used to control animals (usually horses), as per this picture, It’s also used as a verb to indicate situation where control must be exerted, e.g., the spending must be reined in.

Reining Sliding Stop Mannheim Maimarkt 2007 Date 01.05.2007 Source  Own work Author AllX [downloaded from http://en.wikipedia.org/wiki/File:Reining_slidingstop.jpg]

Reining Sliding Stop Mannheim Maimarkt 2007 Date 01.05.2007 Credit: AllX [downloaded from http://en.wikipedia.org/wiki/File:Reining_slidingstop.jpg]

 This ‘reign’ usually references people like these,

“Queen Elizabeth II greets employees on her walk from NASA’s Goddard Space Flight Center mission control to a reception in the center’s main auditorium in Greenbelt, Maryland where she was presented with a framed Hubble image by Congressman Steny Hoyer and Senator Barbara Mikulski. Queen Elizabeth II and her husband, Prince Philip, Duke of Edinburgh, visited the NASA Goddard Space Flight Center as one of the last stops on their six-day United States visit.” Credit: NASA/Bill Ingalls [downloaded from http://en.wikipedia.org/wiki/File:Elizabeth_II_greets_NASA_GSFC_employees,_May_8,_2007_edit.jpg]

“Queen Elizabeth II greets employees on her walk from NASA’s Goddard Space Flight Center mission control to a reception in the center’s main auditorium in Greenbelt, Maryland where she was presented with a framed Hubble image by Congressman Steny Hoyer and Senator Barbara Mikulski. Queen Elizabeth II and her husband, Prince Philip, Duke of Edinburgh, visited the NASA Goddard Space Flight Center as one of the last stops on their six-day United States visit.” Credit: NASA/Bill Ingalls [downloaded from http://en.wikipedia.org/wiki/File:Elizabeth_II_greets_NASA_GSFC_employees,_May_8,_2007_edit.jpg]

 And,

Thailand's King Bhumibol Adulyadej waves to well-wishers during a concert at Siriraj hospital in Bangkok on September 29, 2010. Credit: Government of Thailand [downloaded from http://en.wikipedia.org/wiki/File:King_Bhumibol_Adulyadej_2010-9-29.jpg]

Thailand’s King Bhumibol Adulyadej waves to well-wishers during a concert at Siriraj hospital in Bangkok on September 29, 2010. Credit: Government of Thailand [downloaded from http://en.wikipedia.org/wiki/File:King_Bhumibol_Adulyadej_2010-9-29.jpg]

Kings, Queens, etc. reign over or rule their subjects or they have reigns, i.e., the period during which they hold the position of queen/king, etc. There are also uses such as this one found in the song title ‘Love Reign O’er Me’ (Pete Townshend)

I’ve lost count of the times I’ve seen ‘reigns’ used in place of ‘reins’, the worst part being? I’ve caught myself making the mistake. So, a heartfelt thank you to the NIST news release writer for getting it right. As for the other ‘rains’, neither I not anyone else seems to make that mistake (so far as I’ve seen).

Now on to the news,

You might think that a pair of parallel plates hanging motionless in a vacuum just a fraction of a micrometer away from each other would be like strangers passing in the night—so close but destined never to meet. Thanks to quantum mechanics, you would be wrong.

Scientists working to engineer nanoscale machines know this only too well as they have to grapple with quantum forces and all the weirdness that comes with them. These quantum forces, most notably the Casimir effect, can play havoc if you need to keep closely spaced surfaces from coming together.

Controlling these effects may also be necessary for making small mechanical parts that never stick to each other, for building certain types of quantum computers, and for studying gravity at the microscale.

In trying to solve the problem of keeping closely spaced surfaces from coming together, the scientists uncovered another problem,

One of the insights of quantum mechanics is that no space, not even outer space, is ever truly empty. It’s full of energy in the form of quantum fluctuations, including fluctuating electromagnetic fields that seemingly come from nowhere and disappear just as fast.

Some of this energy, however, just isn’t able to “fit” in the submicrometer space between a pair of electromechanical contacts. More energy on the outside than on the inside results in a kind of “pressure” called the Casimir force, which can be powerful enough to push the contacts together and stick.

Prevailing theory does a good job describing the Casimir force between featureless, flat surfaces and even between most smoothly curved surfaces. However, according to NIST researcher and co-author of the paper, Vladimir Aksyuk, existing theory fails to predict the interactions they observed in their experiment.

“In our experiment, we measured the Casimir attraction between a gold-coated sphere and flat gold surfaces patterned with rows of periodic, flat-topped ridges, each less than 100 nanometers across, separated by somewhat wider gaps with deep sheer-walled sides,” says Aksyuk. “We wanted to see how a nanostructured metallic surface would affect the Casimir interaction, which had never been attempted with a metal surface before. Naturally, we expected that there would be reduced attraction between our grooved surface and the sphere, regardless of the distance between them, because the top of the grooved surface presents less total surface area and less material. However, we knew the Casimir force’s dependence on the surface shape is not that simple.”

Indeed, what they found was more complicated.

According to Aksyuk, when they increased the separation between the surface of the sphere and the grooved surface, the researchers found that the Casimir attraction decreased much more quickly than expected. When they moved the sphere farther away, the force fell by a factor of two below the theoretically predicted value. When they moved the sphere surface close to the ridge tops, the attraction per unit of ridge top surface area increased.

“Theory can account for the stronger attraction, but not for the too-rapid weakening of the force with increased separation,” says Aksyuk. “So this is new territory, and the physics community is going to need to come up with a new model to describe it.”

For the curious, here’s a link to and a citation for the research paper,

Strong Casimir force reduction through metallic surface nanostructuring by Francesco Intravaia, Stephan Koev, Il Woong Jung, A. Alec Talin, Paul S. Davids, Ricardo S. Decca, Vladimir A. Aksyuk, Diego A. R. Dalvit, & Daniel López. Nature Communications 4, Article number: 2515 doi:10.1038/ncomms3515 Published 27 September 2013.

This article is open access.

Ballooning with carbon nanotubes on behalf of climate science

What a gorgeous picture!

Scientific balloon launched from New Mexico in September 2013 carrying an experimental instrument designed to collect and measure the energy of light emitted by the Sun, with the help of NIST chips coated with carbon nanotubes. Credit: LASP

Scientific balloon launched from New Mexico in September 2013 carrying an experimental instrument designed to collect and measure the energy of light emitted by the Sun, with the help of NIST chips coated with carbon nanotubes.
Credit: LASP

US National Institute of Standards and Technology (NIST) researchers made the carbon nanotube chips which help the instruments in the pictured balloon (above) to collect data about light. From the Oct. 24, 2013 news item on Nanowerk,,

A huge plastic balloon floated high in the skies over New Mexico on Sept. 29, 2013, carrying instruments to collect climate-related test data with the help of carbon nanotube chips made by the National Institute of Standards and Technology (NIST).

The onboard instrument was an experimental spectrometer designed to collect and measure visible and infrared wavelengths of light ranging from 350 to 2,300 nanometers. Simpler, lighter and less expensive than conventional counterparts, the spectrometer was tested to determine how accurately it can measure the relative energy of light emitted by the Sun and subsequently reflected or scattered by the Earth and Moon.

The Oct. 22, 2013 NIST news release, which originated the news item, provides some additional detail (Note: Footnotes have been removed),

Researchers at NIST’s Boulder, Colo., campus made the spectrometer’s “slit,” a high-precision chip that selected the entering light. The device was made under a recent agreement between NIST and the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics (LASP). The slit was then calibrated at NIST’s Gaithersburg, Md., headquarters.

For nearly a decade, NIST Boulder researchers have been using carbon nanotubes, the darkest material on Earth, to make coatings for laser power detectors. Nanotubes efficiently absorb nearly all light across a broad span of wavelengths, a useful feature for reducing internal scatter in the balloon imager. NIST also has facilities for, and expertise in, pairing nanotubes with micromachined silicon chips.

The Oct. 1, 2013 LASP (University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics) news release about the project offers information about the climate change data the researchers are hoping to collect and about the spectrometer being used for that purpose,

The instrument, funded by a $4.7 million NASA Earth Science Technology Office Instrument Incubator Program contract, is intended to acquire extremely accurate radiometric measurements of Earth relative to the incident sunlight. Over time, such measurements can tell scientists about changes in land-use, vegetation, urban landscape use, and atmospheric conditions on our planet. Such long-term radiometric measurements from the HyperSpectral Imager for Climate Science (HySICS) instrument can then help scientists identify the drivers of climate change.

Greg Kopp, HySICS Principal Investigator and CU-LASP research scientist, said, “HySICS allows us to acquire an accurate baseline of current Earth conditions so that we can monitor changes that are so relevant to society. This high altitude balloon flight was the first of two to demonstrate the instrument’s potential space capabilities needed to extend the measurements around the globe and over longer times.”

The instrument relies on precise measurements of the Sun for on-orbit calibrations. These solar measurements provide calibrations of the Earth measurements against this well-measured solar reference that other high accuracy space assets provide. Based on accurate solar calibrations, the HySICS radiometric measurements of the Earth can thus establish a long-term data record that is ten times more accurate than any current measurements.

For anyone interested in a more technical description of the device, the NIST news release has this,

For the balloon spectrometer, known as HySICS (HyperSpectral Imager for Climate Science), NIST made two types of custom chips that were stacked together in a sandwich. In the middle were aperture chips, coated with aluminum to block light transmission through the silicon, with small rectangular openings etched into the chip to allow light into the instrument.

A precision spectrometer must ensure that it only gathers light coming directly from its target, so the two outer layers of the sandwich were masking chips—larger openings etched at an angle and coated with tall, thin carbon nanotubes. These VANTAs (“vertically aligned nanotube arrays”) act as superefficient sponges to absorb scattered or stray light across the entire spectral range of the Sun.

While the balloon was in flight, the spectrometer scanned the slit across the Sun to measure solar irradiance. Spectral filters were calibrated by scanning the slit across the Moon and making measurements with and without filters in the beam path. The spectrometer also imaged light emitted from the Earth using the Sun as a reference light source.

For the information junkies amongst us, the Oct. 22, 2013 NIST news release offers links to more information about carbon nanotubes, etc. while the Oct. 1, 2013 LASP news release offers contact information for lead researcher, Greg Kopp.

First ever UN (United Nations) Scientific Advisory Board launches with 26 members

Thanks to David Bruggeman and his Oct. 23, 2013 posting (on the Pasco Phronesis blog where he tracks science policy issues in the US and other countries/jurisdictions as he is able) for information about the UN (United Nations) and its new scientific advisory board (Note: Links have been removed),

Ending the beginning of a process that has been at least a year in the making, the United Nation named the first members of the Secretary-General’s Scientific Advisory Board (H/T ScienceInsider).

Here’s more from the Oct. 18, 2013 UN press release,

Twenty-six eminent scientists, representing natural, social and human sciences and engineering, have been appointed to a Scientific Advisory Board, announced by the UN Secretary-General, Ban Ki-moon. The new Board will provide advice on science, technology and innovation (STI) for sustainable development to the UN Secretary-General and to Executive Heads of UN organizations. UNESCO will host the Secretariat for the Board.

The members of the Scientific Advisory Board are:

·         Tanya Abrahamse (South Africa), CEO, South African National Biodiversity Institute;

·         Susan Avery (United States of America), President and Director, Woods Hole Oceanographic Institution;

·         Hilary McDonald Beckles (Barbados), Pro-Vice Chancellor and Principal, University of the West Indies;

·         Joji Cariño (Philippines), Director, Forest Peoples Programme;

·         Rosie Cooney (Australia), Visiting Fellow, University of Sciences, Sydney;

·         Abdallah Daar (Oman), Professor of Public Health, University of Toronto, Canada;

·         Gebisa Ejeta (Ethiopia), Professor of Agronomy, Purdue University, United States;

·         Vladimir Fortov (Russian Federation), President of the Russian Academy of Sciences;

·         Fabiola Gianotti (Italy), Research physicist and former Coordinator of ATLAS Experiment, CERN, Geneva, Switzerland;

·         Ke Gong (China), President of Nankai University;

·         Jörg Hinrich Hacker (Germany), President, German National Academy of Sciences – Leopoldina;

·         Maria Ivanova (Bulgaria), Professor of Global Governance, University of Massachusetts, United States;

·         Eugenia Kalnay (Argentina), Professor of Atmospheric and Ocean Sciences, University of Maryland, Unites States;

·         Eva Kondorosi (Hungary), Research Professor, Biological Research Centre, Academy of Sciences of Hungary;

·         Reiko Kuroda (Japan), Professor, Research Institute for Science and Technology, Tokyo University of Science;

·         Dong-Pil Min (Republic of Korea), Emeritus Professor, Seoul National University;

·         Carlos Nobre (Brazil), Senior Climate Scientist, National Secretary for R&D Policies;

·         Rajendra Kumar Pachauri (India), Director-General, The Energy and Resources Institute (TERI); Chair, Intergovernmental Panel on Climate Change – Nobel Laureate for Peace;

·         Shankar Sastry (United States of America), Dean, College of Engineering, University of California, Berkeley;

·         Hayat Sindi (Saudi Arabia), Founder and CEO, Institute of Imagination and Ingenuity;

·         Wole Soboyejo (Nigeria), President, African University of Science and Technology (AUST), Garki;

·         Laurence Tubiana (France), Director, Institute of Sustainable Development and International Relations (IDDRI), Paris;

·         Judi Wakhungu (Kenya), Professor of Energy Resources Management, First Cabinet Secretary, Ministry for Environment, Water and Natural Resources;

·         Ada Yonath (Israel), Director, Helen and  Milton A. Kimmelman Centre for Biomolecular Structure and Assembly, Weizmann Institute of Sciences; Nobel Laureate in Chemistry;

·         Abdul Hamid Zakri (Malaysia), Science Advisor to the Prime Minister of Malaysia; Chair, Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES);

·         Ahmed Zewail (Egypt), Director, Department of Chemistry and Chemical Engineering, California Institute of Technology, United States; Nobel Laureate in Chemistry.

The countries listed beside the individual member’s names appears to be their country of origin, e.g., Abdallah Daar (Oman), Professor of Public Health, University of Toronto, Canada, which may or may not be where they are currently located. In any event, they seem to have representation from every continent in one way or another. One other observation, it seems that the gender split is either 50/50 or tilted toward participation from women. (I’m not familiar enough with some of the language groups to be able to identify male as opposed to female first names, not to mention names that are androgynous.)

Moving on, I found these passages of the UN’s news release of particular interest,

“The creation of the Scientific Advisory Board follows on a wide-ranging consultation work entrusted to UNESCO by the UN Secretary-General Ban Ki-moon,” said UNESCO Director-General Irina Bokova.  “It brings together scientists of international stature, and will serve as a global reference point to improve links between science and public policies.”

The Board is the first such body set up by the UN Secretary-General to influence and shape action by the international community to advance sustainable development and eradicate poverty. The initiative derives from the report of the UN Secretary-General’s High-level Panel on Global Sustainability Resilient People, Resilient Planet: A Future worth choosing (January, 2012). This report recommended the launch of a “major global scientific initiative to strengthen the interface between policy and science. This should include the preparation of regular assessments and digests of the science around such concepts as “planetary boundaries”, “tipping points” and “environmental thresholds” in the context of sustainable development”.

The fields covered by the Board range from the basic sciences, through engineering and technology, social sciences and humanities, ethics, health, economic, behavioral, and agricultural sciences, in addition to the environmental sciences.[emphasis mine]

Board members will act in their personal capacity and will provide advice on a strictly independent basis. They will serve pro bono for two years, with the possibility of renewal for one further two-year term, upon the decision of the Secretary-General. The first session of the Board will be held at the beginning of 2014.

I applaud the range of fields they’ve tried to include in the advisory board. As for serving pro bomo for two years, that’s very good of the individual appointees. Still, It’s hard to know how much time will be required and I doubt anyone is going to be out-of-pocket, as presumably there will be trips and other perks courtesy of the UN or home institutions or someone’s national budget. There’s also the prestige associated with being appointed by the UN to this advisory council (good for the CV), not to mention the networking possibilities that could open up.

Despite pointing out that this is not entirely selfless service, I wish the members of UN’s Scientific Advisory Board well in their efforts.

Chameleon materials

Harvard’s School of Engineering and Applied Sciences researchers discovered some unexpected properties when testing a new coating according to an Oct. 22, 2013 news item on Azonano,

Active camouflage has taken a step forward at the Harvard School of Engineering and Applied Sciences (SEAS), with a new coating that intrinsically conceals its own temperature to thermal cameras.

In a laboratory test, a team of applied physicists placed the device on a hot plate and watched it through an infrared camera as the temperature rose. Initially, it behaved as expected, giving off more infrared light as the sample was heated: at 60 degrees Celsius it appeared blue-green to the camera; by 70 degrees it was red and yellow. At 74 degrees it turned a deep red—and then something strange happened. The thermal radiation plummeted. At 80 degrees it looked blue, as if it could be 60 degrees, and at 85 it looked even colder. Moreover, the effect was reversible and repeatable, many times over.

The Oct. 21, 2013 Harvard University news release (also on EurekAlert), which originated the news item, discusses the potential for this discovery and describes the process of discovery in more detail (Note: A link has been removed),

Principal investigator Federico Capasso, Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering at Harvard SEAS, predicts that with only small adjustments the coating could be used as a new type of thermal camouflage or as a kind of encrypted beacon to allow soldiers to covertly communicate their locations in the field.

The secret to the technology lies within a very thin film of vanadium oxide, an unusual material that undergoes dramatic electronic changes when it reaches a particular temperature. At room temperature, for example, pure vanadium oxide is electrically insulating, but at slightly higher temperatures it transitions to a metallic, electrically conductive state. During that transition, the optical properties change, too, which means special temperature-dependent effects—like infrared camouflage—can also be achieved.

The insulator-metal transition has been recognized in vanadium oxide since 1959. However, it is a difficult material to work with: in bulk crystals, the stress of the transition often causes cracks to develop and can shatter the sample. Recent advances in materials synthesis and characterization—especially those by coauthor Shriram Ramanathan, Associate Professor of Materials Science at Harvard SEAS—have allowed the creation of extremely pure samples of thin-film vanadium oxide, enabling a burst of new science and engineering to take off in just the last few years.

“Thanks to these very stable samples that we’re getting from Prof. Ramanathan’s lab, we now know that if we introduce small changes to the material, we can dramatically change the optical phenomena we observe,” explains lead author Mikhail Kats, a graduate student in Capasso’s group at Harvard SEAS. “By introducing impurities or defects in a controlled way via processes known as doping, modifying, or straining the material, it is possible to create a wide range of interesting, important, and predictable behaviors.”

By doping vanadium oxide with tungsten, for example, the transition temperature can be brought down to room temperature, and the range of temperatures over which the strange thermal radiation effect occurs can be widened. Tailoring the material properties like this, with specific outcomes in mind, may enable engineering to advance in new directions.

The researchers say a vehicle coated in vanadium oxide tiles could potentially mimic its environment like a chameleon, appearing invisible to an infrared camera with only very slight adjustments to the tiles’ actual temperature—a far more efficient system than the approaches in use today.

Tuned differently, the material could become a component of a secret beacon, displaying a particular thermal signature on cue to an infrared surveillance camera. Capasso’s team suggests that the material could be engineered to operate at specific wavelengths, enabling simultaneous use by many individually identifiable soldiers.

And, because thermal radiation carries heat, the researchers believe a similar effect could be employed to deliberately speed up or slow down the cooling of structures ranging from houses to satellites.

The Harvard team’s most significant contribution is the discovery that nanoscale structures that appear naturally in the transition region of vanadium oxide can be used to provide a special level of tunability, which can be used to suppress thermal radiation as the temperature rises. The researchers refer to such a spontaneously structured material as a “natural, disordered metamaterial.”

“To artificially create such a useful three-dimensional structure within a material is extremely difficult,” says Capasso. “Here, nature is giving us what we want for free. By taking these natural metamaterials and manipulating them to have all the properties we want, we are opening up a new area of research, a completely new direction of work. We can engineer new devices from the bottom up.”

Here’s an image, from the scientists, illustrating the material’s thermal camouflage (or chameleon) properties,

A new coating intrinsically conceals its own temperature to thermal cameras. (Image courtesy of Mikhail Kats.)

A new coating intrinsically conceals its own temperature to thermal cameras. (Image courtesy of Mikhail Kats.)

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

Vanadium Dioxide as a Natural Disordered Metamaterial: Perfect Thermal Emission and Large Broadband Negative Differential Thermal Emittance by Mikhail A. Kats, Romain Blanchard, Shuyan Zhang, Patrice Genevet, Changhyun Ko, Shriram Ramanathan, and Federico Capasso. Phys. Rev. X » Volume 3 » Issue 4  or Phys. Rev. X 3, 041004 (2013) DOI:10.1103/PhysRevX.3.041004

This paper is published in an open access journal according to the Harvard news release,

About Physical Review X

Launched in August 2011, PRX (http://prx.aps.org) is an open-access, peer-reviewed publication of the American Physical Society (www.aps.org), a non-profit membership organization working to advance and diffuse the knowledge of physics through its outstanding research journals, scientific meetings, and education, outreach, advocacy and international activities. APS represents 50,000 members, including physicists in academia, national laboratories and industry in the United States and throughout the world.