Monthly Archives: September 2018

Spooling strips of graphene

An April 18, 2018 news item on phys.org highlights an exciting graphene development at the Massachusetts Institute of Technology (MIT),

MIT engineers have developed a continuous manufacturing process that produces long strips of high-quality graphene.

The team’s results are the first demonstration of an industrial, scalable method for manufacturing high-quality graphene that is tailored for use in membranes that filter a variety of molecules, including salts, larger ions, proteins, or nanoparticles. Such membranes should be useful for desalination, biological separation, and other applications.

A new manufacturing process produces strips of graphene, at large scale, for use in membrane technologies and other applications. Image: Christine Daniloff, MIT

An April 17, 2018 MIT news release (also on EurekAlert) by Jennifer Chu, which originated the news item,. provides more detail,

“For several years, researchers have thought of graphene as a potential route to ultrathin membranes,” says John Hart, associate professor of mechanical engineering and director of the Laboratory for Manufacturing and Productivity at MIT. “We believe this is the first study that has tailored the manufacturing of graphene toward membrane applications, which require the graphene to be seamless, cover the substrate fully, and be of high quality.”

Hart is the senior author on the paper, which appears online in the journal Applied Materials and Interfaces. The study includes first author Piran Kidambi, a former MIT postdoc who is now an assistant professor at Vanderbilt University; MIT graduate students Dhanushkodi Mariappan and Nicholas Dee; Sui Zhang of the National University of Singapore; Andrey Vyatskikh, a former student at the Skolkovo Institute of Science and Technology who is now at Caltech; and Rohit Karnik, an associate professor of mechanical engineering at MIT.

Growing graphene

For many researchers, graphene is ideal for use in filtration membranes. A single sheet of graphene resembles atomically thin chicken wire and is composed of carbon atoms joined in a pattern that makes the material extremely tough and impervious to even the smallest atom, helium.

Researchers, including Karnik’s group, have developed techniques to fabricate graphene membranes and precisely riddle them with tiny holes, or nanopores, the size of which can be tailored to filter out specific molecules. For the most part, scientists synthesize graphene through a process called chemical vapor deposition, in which they first heat a sample of copper foil and then deposit onto it a combination of carbon and other gases.

Graphene-based membranes have mostly been made in small batches in the laboratory, where researchers can carefully control the material’s growth conditions. However, Hart and his colleagues believe that if graphene membranes are ever to be used commercially they will have to be produced in large quantities, at high rates, and with reliable performance.

“We know that for industrialization, it would need to be a continuous process,” Hart says. “You would never be able to make enough by making just pieces. And membranes that are used commercially need to be fairly big – some so big that you would have to send a poster-wide sheet of foil into a furnace to make a membrane.”

A factory roll-out

The researchers set out to build an end-to-end, start-to-finish manufacturing process to make membrane-quality graphene.

The team’s setup combines a roll-to-roll approach – a common industrial approach for continuous processing of thin foils – with the common graphene-fabrication technique of chemical vapor deposition, to manufacture high-quality graphene in large quantities and at a high rate. The system consists of two spools, connected by a conveyor belt that runs through a small furnace. The first spool unfurls a long strip of copper foil, less than 1 centimeter wide. When it enters the furnace, the foil is fed through first one tube and then another, in a “split-zone” design.

While the foil rolls through the first tube, it heats up to a certain ideal temperature, at which point it is ready to roll through the second tube, where the scientists pump in a specified ratio of methane and hydrogen gas, which are deposited onto the heated foil to produce graphene.

“Graphene starts forming in little islands, and then those islands grow together to form a continuous sheet,” Hart says. “By the time it’s out of the oven, the graphene should be fully covering the foil in one layer, kind of like a continuous bed of pizza.”

As the graphene exits the furnace, it’s rolled onto the second spool. The researchers found that they were able to feed the foil continuously through the system, producing high-quality graphene at a rate of 5 centimers per minute. Their longest run lasted almost four hours, during which they produced about 10 meters of continuous graphene.

“If this were in a factory, it would be running 24-7,” Hart says. “You would have big spools of foil feeding through, like a printing press.”

Flexible design

Once the researchers produced graphene using their roll-to-roll method, they unwound the foil from the second spool and cut small samples out. They cast the samples with a polymer mesh, or support, using a method developed by scientists at Harvard University, and subsequently etched away the underlying copper.

“If you don’t support graphene adequately, it will just curl up on itself,” Kidambi says. “So you etch copper out from underneath and have graphene directly supported by a porous polymer – which is basically a membrane.”

The polymer covering contains holes that are larger than graphene’s pores, which Hart says act as microscopic “drumheads,” keeping the graphene sturdy and its tiny pores open.

The researchers performed diffusion tests with the graphene membranes, flowing a solution of water, salts, and other molecules across each membrane. They found that overall, the membranes were able to withstand the flow while filtering out molecules. Their performance was comparable to graphene membranes made using conventional, small-batch approaches.

The team also ran the process at different speeds, with different ratios of methane and hydrogen gas, and characterized the quality of the resulting graphene after each run. They drew up plots to show the relationship between graphene’s quality and the speed and gas ratios of the manufacturing process. Kidambi says that if other designers can build similar setups, they can use the team’s plots to identify the settings they would need to produce a certain quality of graphene.

“The system gives you a great degree of flexibility in terms of what you’d like to tune graphene for, all the way from electronic to membrane applications,” Kidambi says.

Looking forward, Hart says he would like to find ways to include polymer casting and other steps that currently are performed by hand, in the roll-to-roll system.

“In the end-to-end process, we would need to integrate more operations into the manufacturing line,” Hart says. “For now, we’ve demonstrated that this process can be scaled up, and we hope this increases confidence and interest in graphene-based membrane technologies, and provides a pathway to commercialization.”

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

A Scalable Route to Nanoporous Large-Area Atomically Thin Graphene Membranes by Roll-to-Roll Chemical Vapor Deposition and Polymer Support Casting by Piran R. Kidambi, Dhanushkodi D. Mariappan, Nicholas T. Dee, Andrey Vyatskikh, Sui Zhang, Rohit Karnik, and A. John Hart. ACS Appl. Mater. Interfaces, 2018, 10 (12), pp 10369–10378 DOI: 10.1021/acsami.8b00846 Publication Date (Web): March 19, 2018

Copyright © 2018 American Chemical Society

This paper is behind a paywall.

Finally, there is a video of the ‘graphene spooling out’ process,

The secret behind the world’s lightest chronograph watch (whisper: it’s graphene)

This latest watch from the Richard Mille company by way of the University of Manchester isn’t the lightest watch the company has ever made but it is their lightest, most complex watch yet at less than 1.5 oz. It also has a breathtaking price tag. More about that later.

An August 29, 2018 news item on Nanowerk announces the publication of research related to the graphene-enhanced watch,

In January 2017 the world’s lightest mechanical chronograph watch was unveiled in Geneva, Switzerland, showcasing innovative composite development by using graphene. Now the research behind the project has been published. The unique precision-engineered watch was a result of collaboration between The University of Manchester [UK], Richard Mille Watches and McLaren Applied Technologies.

An August 29, 2018 University of Manchester press release, which originated the news item, gives further detail,

The RM 50-03 watch was made using a unique composite incorporating graphene to manufacture a strong but lightweight new case to house the watch mechanism which weighed just 40 grams in total, including the strap.

The collaboration was an exercise in engineering excellence, exploring the methods of correctly aligning graphene within a composite to make the most of the two-dimensional materials superlative properties of mechanical stiffness and strength whilst negating the need for the addition of other, weightier materials.

Now the research behind this unique watch has been published in the journal, Composites Part A: Applied Science and Manufacturing. The work was primarily carried out by a group of researchers at The University of Manchester’s National Graphene Institute.

Leading the research Professor Robert Young said: “In this work, through the addition of only a small amount of graphene into the matrix, the mechanical properties of a unidirectionally-reinforced carbon fibre composite have been significantly enhanced.

“This could have future impact on precision-engineering industries where strength, stiffness and product weight are key concerns such in as aerospace and automotive.”

The small amount of graphene used was added to a carbon fibre composite with the goal of improving stiffness and reducing weight by requiring the use of less overall material. Since graphene has high levels of stiffness and strength, its use as a reinforcement

in polymer composites shows huge potential of further enhancing the mechanical properties of composites.

The final results were achieved with only a 2% weight fraction of graphene added to the epoxy resin. The resulting composite with graphene and carbon fibre was then analysed by tensile testing and the mechanisms were revealed primarily by using Raman spectroscopy and X-ray CT scans.

The benefits of this research demonstrate a simple method which can be incorporated into existing industrial processes, allowing for engineering industries to benefit from graphene mechanical properties, such as the manufacture of airplane wings or the body work of high-performance cars.

The research group discovered that when comparing with a carbon fibre equivalent specimen, the addition of graphene significantly improved the tensile stiffness and strength. This occurred when the graphene was dispersed through the material and aligned in in the fibre direction.

Dr Zheling Li, a University of Manchester Research Associate said: “This study presents a way of increasing the axial stiffness and strength of composites by simple conventional processing methods, and clarifying the mechanisms that lead to this reinforcement.”

Aurèle Vuilleumier R&D Manager at Richard Mille said: “This project is a perfect example of technology transfer from the university to the product. The partnership with McLaren Applied Technologies allows a broad diffusion of graphene-enhanced composites in the industry. As a tangible result, a world record light and strong watch was available for our customers: the RM 50-03.”

Dr Broderick Coburn, Senior Mechanical Design Engineer at McLaren Applied Technologies said: “The potential of graphene to enhance composites’ structural properties has been known and demonstrated at a lab-scale for some time now. This application, although niche, is a great example of those structural benefits making it through to a prepreg material, and then into an actual product.”

The University of Manchester will soon be celebrating the opening of its second world-class graphene facility, the Graphene Engineering Innovation Centre (GEIC), set-to open later this year. The GEIC will allow industry to work alongside academic expertise to translate research into prototypes and pilot production and accelerate the commercialisation of graphene.

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

Realizing the theoretical stiffness of graphene in composites through confinement between carbon fibers by Jingwen Chu, Robert J.Young, Thomas J.A.Slater, Timothy L.Burnett, Broderick Coburn, Ludovic Chichignoud, Aurèle Vuilleumier, Zheling Li. Composites Part A: Applied Science and Manufacturing Volume 113, October 2018, Pages 311-317 DOI: https://doi.org/10.1016/j.compositesa.2018.07.032

This paper is open access.

Price tag?

There’s an old saying, ‘if you have to ask, you can’t afford it’. It sprang to mind as I checked out the luxury Swiss watch company’s, Richard MIlle, products. You won’t find a price tag on the company’s RM 50-03’s product page but you will get lots of pictures of the watch mixed in with sports car images alongside chunks of text exhorting the watch and invoking sports car racing, a very expensive sport. And, the sports car images make even more sense when you know that the one of other partners in this academic/commercial venture is a UK leader in the field of motorsport. More from the About page on the McLaren website,

Whatever we apply ourselves to at McLaren, whether in the fields of racing, supercars or technology; we are committed to a journey of relentless improvement that challenges convention, disrupts markets and delivers powerful competitive advantage.

I was not able to find a price list on the Mille or McLaren sites. In fact, the watch does not seem to be mentioned at all on the McLaren website.

Happily, there’s a January 17, 2017 posting by Zach Pina for A Blog To Watch, which kind of reveals the price (Note: Links have been removed),

Forty grams [less than 1.5 oz.]. That’s the total weight, including the strap, of the new Richard Mille RM 50-03 McLaren F1 watch, making it the lightest split-second chronograph with a tourbillon the world has ever seen. Ok, yes – this isn’t exactly an ultra-competitive category – hell, the RM 50-03 is a veritable boat-anchor when compared to the groundbreaking 19-gram [less that .75 oz.] RM 027 Tourbillon Richard Mille built for Rafael Nadal, but that was, by comparison, a much less complicated watch. A mere 40 grams is still an impressive technical feat when you look at just how much is packed into the latest marvel from Richard Mille. The cost for the 40-gram horological wonder? It’ll be seven figures. [The blog post’s title has the price as $1Million.]

Sports cars are expensive and, I guess, so is the technology when it’s adapted to watches. If you’re at all interested, watches, luxury products, and/or the latest high technology, I recommend reading Pina’s entire posting for a lively read,

Richard Mille is no slouch when it comes to passionately creative design and materials (possible understatement of the year, though the year [2017] is still young). However, in breaking new ground for this particular watch, it took a partnership between the Swiss watchmaker, famed British Formula 1 automaker McLaren, and Nobel Prize-winning scientists from the University of Manchester. The product of their collaboration is a case that marries titanium, carbon TPT (thin-ply technology), and a Richard Mille exclusive and apparent watchmaking first: Graph TPT, better known as graphene, that is six times lighter than steel and 200 times as strong. It’s on the cutting edge of materials research and sets the bar for lightweight strength in timepieces.

Should you be hoping for a bargain, I don’t expect they’ve dropped the price in an effort to move product as it reaches its second anniversary since part of the appeal of a luxury product is the cost. In fact, luxury brands destroy product rather than lower the price,

Published on Jul 19, 2018

Burberry is amongst some luxury brands that are burning their stock. Millions of pounds of waste being incinerated to retain exclusivity.

 

Since media have started reporting on this practice, it seems luxury brands are reconsidering their practices.

Pancakes & booze (underground) art show on Sept. 28, 2018 in Toronto and North Carolina’s public call for art for the upcoming exhibition Art’s Work in the Age of Biotechnology: Shaping our Genetic Futures.

Pancakes & booze

From an August 12, 2018 Art/Sci Salon announcement (received via email),

Toronto — Batter sizzles, beer foams, and bare flesh is slathered in paint as gawkers look on. Indie musicians and DJs thunder sound waves off the canvas-lined, graffiti-strewn walls. Revelers stuff their faces with endless pancakes.

What is this, some type of hipster themed IHOP? A Lady Gaga video? Bansky’s mom’s basement? Nah, it’s the Pancakes & Booze Art Show – the hottest pop-up traveling art event in all the land.

This is no stuffy wine-and-cheese, someone-gag-me-with-a-cocktail-napkin gallery. It’s an innovative reimagining of the art show concept, as DIY art movement mayhem. Up-and-coming artists strut and sell their stuff in a freeverse, electric funhouse of mayhem.

You know you want to come, right? Hit me up so we can talk about ways to convince your editor to pay you to visit the show and maybe relax that no-alcohol-on-the-job policy. Hell, even bring your boss along If you like.

WHAT: Pancakes & Booze Art Show: Over 80 emerging artists showcasing their hottest work in a Warhol-style, anything-goes, massive warehouse environment–live music, body painting, multimedia displays, and FREE pancakes!   The show originated in 2009 in Los Angeles and since has popped up more than 300 times in over 35 cities around the world. Each show draws as many as 3000 guests throughout the night.

WHEN:
Friday, September 28
8pm – 2am

WHERE:
The Opera House
735 Queen St. E.
Toronto, Ontario M4M 1H1

ABOUT TOM: Tom Kirlin, 40, left his movie career as a Hollywood cameraman to start Pancakes & Booze in 2009. Born in Tucson, Ariz., he’s a travel fiend who has visited over forty countries across every continent but Antarctica. At 6-foot-6, he’s a hell of a ringer in pick-up basketball games. Bug him at info@pancakesandbooze.com

There’s also this summary along with additional details from the announcement:

Toronto’s Premier Underground Art Show featuring:

  • 80+ Emerging Local Artists
  • Live Body Painting
  • Live Art
  • Live Music
  • FREE Pancake Bar
  • 21+ EVENT
  • 8pm – 2am
  • $10 – $13

Event info: https://www.facebook.com/events/390234974807730/

Tickets: https://www.brownpapertickets.com/event/3442689

The Opera House
735 Queen St. E.
Toronto, Ontario M4M 1H1

Wanna show some work?
Submit here: www.pancakesandbooze.com/submit

Check us out on

IG @pancakesandbooze

FB @pancakesandboozeartshow
Twitter @pancakesbooze

#pancakesandbooze

North Carolina: Art’s work in the age of biotechnology: Shaping our genetic futures

This too is from an August 12, 2018 Art/Sci Salon email,

This looks good!
Apply!

The NCSU [North Carolina State University] Libraries, NC State’s Genetic Engineering and Society (GES) Center, and the Gregg Museum of Art & Design have issued a public call for art for the upcoming exhibition Art’s Work in the Age of Biotechnology: Shaping our Genetic Futures.

Planned for fall 2019, the multi-site exhibition will be held simultaneously at the Gregg Museum of Art & Design and in the physical and digital display spaces of the NCSU Libraries–the Exhibit Gallery in the D. H. Hilll Library and the video walls in the James B. Hunt Jr. Library. Outdoor and/or greenhouse spaces are also available.

about

Art’s Work/Genetic Futures poses the question: How do artists and designers contribute materially, rhetorically, and conceptually to modern biotechnology? We are looking for contemporary work and project proposals that will engage viewers in examining how genomic sciences could shape the future of our society. Projects that question and challenge current biotechnology tropes, as well as projects that embrace the transformative potential of biotechnology and biomedicine, are welcome.

Guest curator Hannah Star Rogers will organize Art’s Work/Genetic Futures with a panel from the exhibition partners at NC State. Rogers has curated Making Science Visible: The Photography of Berenice Abbott, which received an exhibits prize from the British Society for the History of Science and resulted in an invited lecture at the Smithsonian Archives of American Art. She is past Director of Research and Collaboration forEmerge: Artists and Scientists Redesign the Future 2016 and served as Guest Bioart Curator for 2017.

This call is open to artists, scientists, designers, and makers at all career stages. Emerging artists, creators who are traditionally underrepresented in the arts and sciences, and artists working outside the U.S. are especially encouraged to apply.

Artists will receive an honorarium of $2,500 and three copies of the full-color catalog with essays by the curator and other contributors. Artists working in a collaborative team will share the honorarium.

The deadline for work and proposals is Monday, Oct. 1, 2018.

A shortlist will be announced Thursday, Nov. 15, 2018. Final notification of acceptance will be Tuesday, Jan. 15, 2019.

Full details about the exhibition, the call for art, and how to submit are available on the Art’s Work/Genetic Futures exhibition website at go.ncsu.edu/artswork.

Good luck!

Killer graphene spikes to kill bacteria on medical implants

Implants of all kinds (hip replacements, knee replacements, etc.) seem to be on the rise and along with that an increasing number of infections. A Swedish research team announces a technology that could make implants safer in an April 16, 2018 news item on Nanowerk,

A tiny layer of graphene flakes becomes a deadly weapon and kills bacteria, stopping infections during procedures such as implant surgery. This is the findings of new research from Chalmers University of Technology, Sweden, recently published in the scientific journal Advanced Materials Interfaces (“Vertically Aligned Graphene Coating is Bactericidal and Prevents the Formation of Bacterial Biofilms”).

An April 16, 2018 Chalmers University of Technology press release (also on EurekAlert), which originated the news item, provides more detail about the scope of the problem and the proposed solution (Note: A link has been removed),

Operations for surgical implants, such as hip and knee replacements or dental implants, have increased in recent years. However, in such procedures, there is always a risk of bacterial infection. In the worst case scenario, this can cause the implant to not attach to the skeleton, meaning it must be removed.

Bacteria travel around in fluids, such as blood, looking for a surface to cling on to. Once in place, they start to grow and propagate, forming a protective layer, known as a biofilm.

A research team at Chalmers has now shown that a layer of vertical graphene flakes forms a protective surface that makes it impossible for bacteria to attach. Instead, bacteria are sliced apart by the sharp graphene flakes and killed. Coating implants with a layer of graphene flakes can therefore help protect the patient against infection, eliminate the need for antibiotic treatment, and reduce the risk of implant rejection. The osseointegration – the process by which the bone structure grow to attach the implant – is not disturbed. In fact, the graphene has been shown to benefit the bone cells.

Chalmers University is a leader in the area of graphene research, but the biological applications did not begin to materialise until a few years ago. The researchers saw conflicting results in earlier studies. Some showed that graphene damaged the bacteria, others that they were not affected.

“We discovered that the key parameter is to orient the graphene vertically. If it is horizontal, the bacteria are not harmed” says Ivan Mijakovic, Professor at the Department of Biology and Biological Engineering.

The sharp flakes do not damage human cells. The reason is simple: one bacterium is one micrometer – one thousandth of a millimeter – in diameter, while a human cell is 25 micrometers. So, what constitutes a deadly knife attack for a bacterium, is therefore only a tiny scratch for a human cell.

“Graphene has high potential for health applications. But more research is needed before we can claim it is entirely safe. Among other things, we know that graphene does not degrade easily” says Jie Sun, Associate Professor at the Department of Micro Technology and Nanoscience.

Good bacteria are also killed by the graphene. But that’s not a problem, as the effect is localised and the balance of microflora in the body remains undisturbed.

“We want to prevent bacteria from creating an infection. Otherwise, you may need antibiotics, which could disrupt the balance of normal bacteria and also enhance the risk of antimicrobial resistance by pathogens” says Santosh Pandit, postdoc at Biology and Biological Engineering.

Vertical flakes of graphene are not a new invention, having existed for a few years. But the Chalmers research teams are the first to use the vertical graphene in this way. The next step for the research team will be to test the graphene flakes further, by coating implant surfaces and studying the effect on animal cells.

Chalmers cooperated with Wellspect Healthcare, a company which makes catheters and other medical instruments, in this research. They will now continue with a second study.

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

Vertically Aligned Graphene Coating is Bactericidal and Prevents the Formation of Bacterial Biofilms by Santosh Pandit, Zhejian Cao, Venkata R. S. S. Mokkapati, Emanuele Celauro, Avgust Yurgens, Martin Lovmar, Fredrik Westerlund, Jie Sun, Ivan Mijakovic. Advanced Materials Interfaces Volume5, Issue7 April 9, 2018 Pages 1701331 [sic] https://doi.org/10.1002/admi.201701331 First published [online]: 2 February 2018

This paper is behind a paywall.

Finally, here’s a ‘killer spikes’ video made available by Chalmers University of Technology,

Bloodless diabetes monitor enabled by nanotechnology

There have been some remarkable advances in the treatment of many diseases, diabetes being one of them. Of course, we can always make things better.and monitoring a diabetic patient’s glucose without have to draw blood is an improvement that may occur sooner rather than later as an April 9,2018 news item on Nanowerk suggests,

Scientists have created a non-invasive, adhesive patch, which promises the measurement of glucose levels through the skin without a finger-prick blood test, potentially removing the need for millions of diabetics to frequently carry out the painful and unpopular tests.

The patch does not pierce the skin, instead it draws glucose out from fluid between cells across hair follicles, which are individually accessed via an array of miniature sensors using a small electric current. The glucose collects in tiny reservoirs and is measured. Readings can be taken every 10 to 15 minutes over several hours.

Crucially, because of the design of the array of sensors and reservoirs, the patch does not require calibration with a blood sample — meaning that finger prick blood tests are unnecessary.

The device can measure glucose levels without piercing the skin Courtesy: University of Bath

An April 9, 2018 University of Bath press release, which originated the news item, expands on the theme,

Having established proof of the concept behind the device in a study published in Nature Nanotechnology, the research team from the University of Bath hopes that it can eventually become a low-cost, wearable sensor that sends regular, clinically relevant glucose measurements to the wearer’s phone or smartwatch wirelessly, alerting them when they may need to take action.

An important advantage of this device over others is that each miniature sensor of the array can operate on a small area over an individual hair follicle – this significantly reduces inter- and intra-skin variability in glucose extraction and increases the accuracy of the measurements taken such that calibration via a blood sample is not required.

The project is a multidisciplinary collaboration between scientists from the Departments of Physics, Pharmacy & Pharmacology, and Chemistry at the University of Bath.

Professor Richard Guy, from the Department of Pharmacy & Pharmacology, said: “A non-invasive – that is, needle-less – method to monitor blood sugar has proven a difficult goal to attain. The closest that has been achieved has required either at least a single-point calibration with a classic ‘finger-stick’, or the implantation of a pre-calibrated sensor via a single needle insertion. The monitor developed at Bath promises a truly calibration-free approach, an essential contribution in the fight to combat the ever-increasing global incidence of diabetes.”

Dr Adelina Ilie, from the Department of Physics, said: “The specific architecture of our array permits calibration-free operation, and it has the further benefit of allowing realisation with a variety of materials in combination. We utilised graphene as one of the components as it brings important advantages: specifically, it is strong, conductive, flexible, and potentially low-cost and environmentally friendly. In addition, our design can be implemented using high-throughput fabrication techniques like screen printing, which we hope will ultimately support a disposable, widely affordable device.”

In this study the team tested the patch on both pig skin, where they showed it could accurately track glucose levels across the range seen in diabetic human patients, and on healthy human volunteers, where again the patch was able to track blood sugar variations throughout the day.

The next steps include further refinement of the design of the patch to optimise the number of sensors in the array, to demonstrate full functionality over a 24-hour wear period, and to undertake a number of key clinical trials.

Diabetes is a serious public health problem which is increasing. The World Health Organization predicts the world-wide incidence of diabetes to rise from 171M in 2000 to 366M in 2030. In the UK, just under six per cent of adults have diabetes and the NHS spends around 10% of its budget on diabetes monitoring and treatments. Up to 50% of adults with diabetes are undiagnosed.

An effective, non-invasive way of monitoring blood glucose could both help diabetics, as well as those at risk of developing diabetes, make the right choices to either manage the disease well or reduce their risk of developing the condition. The work was funded by the Engineering and Physical Sciences Research Council (EPSRC), the Medical Research Council (MRC), and the Sir Halley Stewart Trust.

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

Non-invasive, transdermal, path-selective and specific glucose monitoring via a graphene-based platform by Luca Lipani, Bertrand G. R. Dupont, Floriant Doungmene, Frank Marken, Rex M. Tyrrell, Richard H. Guy, & Adelina Ilie. Nature Nanotechnology (2018) doi:10.1038/s41565-018-0112-4 Published online: 09 April 2018

This paper is behind a paywall.

Robust reverse osmosis membranes made of carbon nanotubes

Caption: SEM images of MWCNT-PA (Multi-Walled Carbon Nanotube-Polyamide) nanocomposite membranes, for plain PA, and PA with 5, 9.5, 12.5, 15.5, 17 and 20 wt.% of MWCNT, where the typical lobe-like structures appear at the surface. Note the tendency towards a flatter membrane surface as the content of MWCNT increases. Scale bar corresponds to 1.0?μm for all the micrographs. Credit: Copyright 2018, Springer Nature, Licensed under CC BY 4.0

It seems unlikely that the image’s resemblance to a Japanese kimono on display is accidental. Either way, nicely done!

An April 12, 2018 news item on phys.org describes a technique that would allow large-scale water desalination,

A research team of Shinshu University, Japan, has developed robust reverse osmosis membranes that can endure large-scale water desalination. The team published their results in early February [2018] in Scientific Reports.

“Since more than 97 percent of the water in the world is saline water, reverse osmosis desalination plants for producing fresh water are increasingly important for providing a safe and consistent supply,” said Morinobu Endo, Ph.D., corresponding author on the paper. Endo is a distinguished professor of Shinshu University and the Honorary Director of the Institute of Carbon Science and Technology. “Even though reverse osmosis membrane technology has been under development for several decades, new threats like global warming and increasing clean water demand in populated urban centers challenge the conventional water supply systems.”

Reverse osmosis membranes typically consist of thin film composite systems, with an active layer of polymer film that restricts undesired substances, such as salt, from passing through a permeable porous substrate. Such membranes can turn seawater into drinkable water, as well as aid in agricultural and landscape irrigation, but they can be costly to operate and spend a large amount of energy.

To meet the demand of potable water at low cost, Endo says more robust membranes capable of withstanding harsh conditions, while remaining chemically stable to tolerate cleaning treatments, are necessary. The key lays in carbon nanotechnology.

An April 11, 2018 Shinshu University press release, which originated the news item, provides more details about the work,

Endo is a pioneer of carbon nanotubes [sic] synthesis by catalytic chemical vapor deposition. In this research, Endo and his team developed a multi-walled carbon nanotube-polyamide nanocomposite membrane, which is resistant to chlorine–one of the main cause of degradation or failure cases in reverse osmosis membranes. The added carbon nanotubes create a protective effect that stabilized the linked molecules of the polyamide against chlorine.

“Carbon nanotechnology has been expected to bring benefits, and this is one promising example of the contribution of carbon nanotubes to a very critical application: water purification,” Endo said. “Carbon nanotubes and fibers are already superb reinforcements for other applications in materials science and engineering, and this is yet another field where their exceptional properties can be used for improving conventional technologies.”

The researchers are working to stabilize and expand the production and processing of multi-walled carbon nanotube-polyamide nanocomposite membranes.

“We are currently working on scaling up our method of synthesis, which, in principle, is based on the same method used to prepare current polyamide membranes,” Endo said. He also noted that his team is planning a collaboration to produce commercial membranes.

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

Robust water desalination membranes against degradation using high loads of carbon nanotubes by J. Ortiz-Medina, S. Inukai, T. Araki, A. Morelos-Gomez, R. Cruz-Silva, K. Takeuchi, T. Noguchi, T. Kawaguchi, M. Terrones, & M. Endo. Scientific Reports volume 8, Article number: 2748 (2018) doi:10.1038/s41598-018-21192-5 Published online: 09 February 2018

This paper is open access.

Clean up oil spills (on water and/or land) with oil-eating bacterium

Quebec’s Institut national de la recherche scientifique (INRS) announced an environmentally friendly way of cleaning up oil spills in an April 9, 2018 news item on ScienceDaily,

From pipelines to tankers, oil spills and their impact on the environment are a source of concern. These disasters occur on a regular basis, leading to messy decontamination challenges that require massive investments of time and resources. But however widespread and serious the damage may be, the solution could be microscopic — Alcanivorax borkumensis — a bacterium that feeds on hydrocarbons. Professor Satinder Kaur Brar and her team at INRS have conducted laboratory tests that show the effectiveness of enzymes produced by the bacterium in degrading petroleum products in soil and water. Their results offer hope for a simple, effective, and eco-friendly method of decontaminating water and soil at oil sites.

An April 8, 2018 INRS news release by Stephanie Thibaut, which originated the news item, expands on the theme,

In recent years, researchers have sequenced the genomes of thousands of bacteria from various sources. Research associate Dr.Tarek Rouissi poured over “technical data sheets” for many bacterial strains with the aim of finding the perfect candidate for a dirty job: cleaning up oil spills. He focused on the enzymes they produce and the conditions in which they evolve.

A. borkumensis, a non-pathogenic marine bacterium piqued his curiosity. The microorganism’s genome contains the codes of a number of interesting enzymes and it is classified as “hydrocarbonoclastic”—i.e., as a bacterium that uses hydrocarbons as a source of energy. A. borkumensis is present in all oceans and drifts with the current, multiplying rapidly in areas where the concentration of oil compounds is high, which partly explains the natural degradation observed after some spills. But its remedial potential had not been assessed.

“I had a hunch,” Rouissi said, “and the characterization of the enzymes produced by the bacterium seems to have proven me right!” A. borkumensis boasts an impressive set of tools: during its evolution, it has accumulated a range of very specific enzymes that degrade almost everything found in oil. Among these enzymes, the bacteria’shydroxylases stand out from the ones found in other species: they are far more effective, in addition to being more versatile and resistant to chemical conditions, as tested in coordination by a Ph.D. student, Ms. Tayssir Kadri.

To test the microscopic cleaner, the research team purified a few of the enzymes and used them to treat samples of contaminated soil. “The degradation of hydrocarbons using the crude enzyme extract is really encouraging and reached over 80% for various compounds,” said Brar. The process is effective in removing benzene, toluene, and xylene, and has been tested under a number of different conditions to show that it is a powerful way to clean up polluted land and marine environments.”

The next steps for Brar’s team are to find out more about how these bacteria metabolize hydrocarbons and explore their potential for decontaminating sites. One of the advantages of the approach developed at INRS is its application in difficult-to-access environments, which present a major challenge during oil spill cleanup efforts.

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

Ex-situ biodegradation of petroleum hydrocarbons using Alcanivorax borkumensis enzymes by Tayssir Kadri, Sara Magdouli, Tarek Rouissi, Satinder Kaur Brar. Biochemical Engineering Journal Volume 132, 15 April 2018, Pages 279-287 DOI: https://doi.org/10.1016/j.bej.2018.01.014

This paper is behind a paywall.

In light of this research, it seems remiss not to mention the recent setback for Canada’s Trans Mountain pipeline expansion. Canada’s Federal Court of Appeal quashed the approval as per this August 30, 2018 news item on canadanews.org. There were two reasons for the quashing (1) a failure to properly consult with indigenous people and (2) a failure to adequately assess environmental impacts on marine life. Interestingly, no one ever mentions environmental cleanups and remediation, which could be very important if my current suspicions regarding the outcome for the next federal election are correct.

Regardless of which party forms the Canadian government after the 2019 federal election, I believe that either Liberals or Conservatives would be equally dedicated to bringing this pipeline to the West Coast. The only possibility I can see of a change lies in a potential minority government is formed by a coalition including the NDP (New Democratic Party) and/or the Green Party; an outcome that seems improbable at this juncture.

Given what I believe to be the political will regarding the Trans Mountain pipeline, I would dearly love to see more support for better cleanup and remediation measures.

Proposed nanodevice made possible by particle that is its own antiparticle (Majorana particle)

I’m not sure how much the mystery of Ettore Majorana’s disappearance in 1938 has to do with the latest research from Brazil on Majorana particles but it’s definitely fascinating,. From an April 6, 2018 news item on ScienceDaily,

In March 1938, the young Italian physicist Ettore Majorana disappeared mysteriously, leaving his country’s scientific community shaken. The episode remains unexplained, despite Leonardo Scascia’s attempt to unravel the enigma in his book The Disappearance of Majorana (1975).

Majorana, whom Enrico Fermi called a genius of Isaac Newton’s stature, vanished a year after making his main contribution to science. In 1937, when he was only 30, Majorana hypothesized a particle that is its own anti-particle and suggested that it might be the neutrino, whose existence had recently been predicted by Fermi and Wolfgang Pauli.

Eight decades later, Majorana fermions, or simply majoranas, are among the objects most studied by physicists. In addition to neutrinos — whose nature, whether or not they are majoranas, is one of the investigative goals of the mega-experiment Dune — another class not of fundamental particles but of quasi-particles or apparent particles has been investigated in the field of condensed matter. These Majorana quasi-particles can emerge as excitations in topological superconductors.

An April 6, 2018 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) press release on EurekAlert, which originated the news item,  reveals more about the Brazilian research (Note: Links have been removed),

A new study by PhD student Luciano Henrique Siliano Ricco with a scholarship from the São Paulo Research Foundation – FAPESP, in collaboration with his supervisor Antonio Carlos Ferreira Seridonio and others, was conducted on the Ilha Solteira campus of São Paulo State University (UNESP) in Brazil and described in an article in Scientific Reports.

“We propose a theoretical device that acts as a thermoelectric tuner – a tuner of heat and charge – assisted by Majorana fermions,” Seridonio said.

The device consists of a quantum dot (QD), represented in the Figure A by the symbol ε1. QDs are often called “artificial atoms.” In this case, the QD is located between two metallic leads at different temperatures.

The temperature difference is fundamental to allowing thermal energy to flow across the QD. A quasi-one-dimensional superconducting wire – called a Kitaev wire after its proponent, Russian physicist Alexei Kitaev, currently a professor at the California Institute of Technology (Caltech) in the US – is connected to the QD.

In this study, the Kitaev wire was ring- or U-shaped and had two majoranas (η1 and η2) at its edges. The majoranas emerge as excitations characterized by zero-energy modes.

“When the QD is coupled to only one side of the wire, the system behaves resonantly with regard to electrical and thermal conductance. In other words, it behaves like a thermoelectric filter,” said the principal investigator for the FAPESP fellowship.

“I should stress that this behavior as a filter for thermal and electrical energy occurs when the two majoranas ‘see’ each other via the wire, but only one of them ‘sees’ the QD in the connection.”

Another possibility investigated by the researchers involved making the QD “see” the two majoranas at the same time by connecting it to both ends of the Kitaev wire.

“By making the QD ‘see’ more of η1 or η2, i.e., by varying the system’s asymmetry, we can use the artificial atom as a tuner, where the thermal or electrical energy that flows through it is redshifted or blueshifted,” Seridonio said (see Figure B for illustrative explanation).

This theoretical paper, he added, is expected to contribute to the development of thermoelectric devices based on Majorana fermions.

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

Tuning of heat and charge transport by Majorana fermions by L. S. Ricco, F. A. Dessotti, I. A. Shelykh, M. S. Figueira & A. C. Seridonio. Scientific Reportsvolume 8, Article number: 2790 (2018) doi:10.1038/s41598-018-21180-9 Published online: 12 February 2018

This paper is open access.

As I prepared to publish this piece I stumbled across a sad Sept. 3, 2018 article about Brazil and its overnight loss of heritage in a fire by Henry Grabar for slate.com (Note: Links have been removed),

On Sunday night, a fire ripped through Brazil’s National Museum in Rio de Janeiro, destroying the country’s most valuable storehouse of natural and anthropological history within hours.

Most of the 20 million items housed inside—including the skull of Luzia, the oldest human remains ever found in the Americas; one of the world’s largest archives of South America’s indigenous cultures; more than 26,000 fossils, 55,000 stuffed birds, and 5 million insect specimens; and a library of more than 500,000 books—are thought to have been destroyed.

The loss is a symptom of a larger problem as Grabar notes in his article.