Tag Archives: China

Drive to operationalize transistors that outperform silicon gets a boost

Dexter Johnson has written a Jan. 19, 2017 posting on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers]) about work which could lead to supplanting silicon-based transistors with carbon nanotube-based transistors in the future (Note: Links have been removed),

The end appears nigh for scaling down silicon-based complimentary metal-oxide semiconductor (CMOS) transistors, with some experts seeing the cutoff date as early as 2020.

While carbon nanotubes (CNTs) have long been among the nanomaterials investigated to serve as replacement for silicon in CMOS field-effect transistors (FETs) in a post-silicon future, they have always been bogged down by some frustrating technical problems. But, with some of the main technical showstoppers having been largely addressed—like sorting between metallic and semiconducting carbon nanotubes—the stage has been set for CNTs to start making their presence felt a bit more urgently in the chip industry.

Peking University scientists in China have now developed carbon nanotube field-effect transistors (CNT FETs) having a critical dimension—the gate length—of just five nanometers that would outperform silicon-based CMOS FETs at the same scale. The researchers claim in the journal Science that this marks the first time that sub-10 nanometer CNT CMOS FETs have been reported.

More importantly than just being the first, the Peking group showed that their CNT-based FETs can operate faster and at a lower supply voltage than their silicon-based counterparts.

A Jan. 20, 2017 article by Bob Yirka for phys.org provides more insight into the work at Peking University,

One of the most promising candidates is carbon nanotubes—due to their unique properties, transistors based on them could be smaller, faster and more efficient. Unfortunately, the difficulty in growing carbon nanotubes and their sometimes persnickety nature means that a way to make them and mass produce them has not been found. In this new effort, the researchers report on a method of creating carbon nanotube transistors that are suitable for testing, but not mass production.

To create the transistors, the researchers took a novel approach—instead of growing carbon nanotubes that had certain desired properties, they grew some and put them randomly on a silicon surface and then added electronics that would work with the properties they had—clearly not a strategy that would work for mass production, but one that allowed for building a carbon nanotube transistor that could be tested to see if it would verify theories about its performance. Realizing there would still be scaling problems using traditional electrodes, the researchers built a new kind by etching very tiny sheets of graphene. The result was a very tiny transistor, the team reports, capable of moving more current than a standard CMOS transistor using just half of the normal amount of voltage. It was also faster due to a much shorter switch delay, courtesy of a gate capacitance of just 70 femtoseconds.

Peking University has published an edited and more comprehensive version of the phys.org article first reported by Lisa Zyga and edited by Arthars,

Now in a new paper published in Nano Letters, researchers Tian Pei, et al., at Peking University in Beijing, China, have developed a modular method for constructing complicated integrated circuits (ICs) made from many FETs on individual CNTs. To demonstrate, they constructed an 8-bits BUS system–a circuit that is widely used for transferring data in computers–that contains 46 FETs on six CNTs. This is the most complicated CNT IC fabricated to date, and the fabrication process is expected to lead to even more complex circuits.

SEM image of an eight-transistor (8-T) unit that was fabricated on two CNTs (marked with two white dotted lines). The scale bar is 100 μm. (Copyright: 2014 American Chemical Society)

Ever since the first CNT FET was fabricated in 1998, researchers have been working to improve CNT-based electronics. As the scientists explain in their paper, semiconducting CNTs are promising candidates for replacing silicon wires because they are thinner, which offers better scaling-down potential, and also because they have a higher carrier mobility, resulting in higher operating speeds.

Yet CNT-based electronics still face challenges. One of the most significant challenges is obtaining arrays of semiconducting CNTs while removing the less-suitable metallic CNTs. Although scientists have devised a variety of ways to separate semiconducting and metallic CNTs, these methods almost always result in damaged semiconducting CNTs with degraded performance.

To get around this problem, researchers usually build ICs on single CNTs, which can be individually selected based on their condition. It’s difficult to use more than one CNT because no two are alike: they each have slightly different diameters and properties that affect performance. However, using just one CNT limits the complexity of these devices to simple logic and arithmetical gates.

The 8-T unit can be used as the basic building block of a variety of ICs other than BUS systems, making this modular method a universal and efficient way to construct large-scale CNT ICs. Building on their previous research, the scientists hope to explore these possibilities in the future.

“In our earlier work, we showed that a carbon nanotube based field-effect transistor is about five (n-type FET) to ten (p-type FET) times faster than its silicon counterparts, but uses much less energy, about a few percent of that of similar sized silicon transistors,” Peng said.

“In the future, we plan to construct large-scale integrated circuits that outperform silicon-based systems. These circuits are faster, smaller, and consume much less power. They can also work at extremely low temperatures (e.g., in space) and moderately high temperatures (potentially no cooling system required), on flexible and transparent substrates, and potentially be bio-compatible.”

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

Scaling carbon nanotube complementary transistors to 5-nm gate lengths by Chenguang Qiu, Zhiyong Zhang, Mengmeng Xiao, Yingjun Yang, Donglai Zhong, Lian-Mao Peng. Science  20 Jan 2017: Vol. 355, Issue 6322, pp. 271-276 DOI: 10.1126/science.aaj1628

This paper is behind a paywall.

Soy and cellulose come together for a bionano air filter

A Jan. 18, 2017 news item on Nanowerk describes research into an environmentally friendly air filter from Washington State University,

Washington State University researchers have developed a soy-based air filter that can capture toxic chemicals, such as carbon monoxide and formaldehyde, which current air filters can’t.

The research could lead to better air purifiers, particularly in regions of the world that suffer from very poor air quality. …

Working with researchers from the University of Science and Technology Beijing, the WSU team, including Weihong (Katie) Zhong, professor in the School of Mechanical and Materials Engineering, and graduate student Hamid Souzandeh, used a pure soy protein along with bacterial cellulose for an all-natural, biodegradable, inexpensive air filter.

Here’s an image the researchers have made available,

Bionano air filter before and after filtration. Courtesy: Washington State University

A Jan. 12, 2017 Washington State University news release by Tilda Hilding, which originated the news item, expands on the theme,

Poor air quality causes health problems worldwide and is a factor in diseases such as asthma, heart disease and lung cancer. Commercial air purifiers aim for removing the small particles that are present in soot, smoke or car exhaust because these damaging particles are inhaled directly into the lungs.

With many sources of pollution in some parts of the world, however, air pollution also can contain a mix of hazardous gaseous molecules, such as carbon monoxide, formaldehyde, sulfur dioxide and other volatile organic compounds.

Typical air filters, which are usually made of micron-sized fibers of synthetic plastics, physically filter the small particles but aren’t able to chemically capture gaseous molecules. Furthermore, they’re most often made of glass and petroleum products, which leads to secondary pollution, Zhong said.

Soy captures nearly all pollutants

The WSU and Chinese team developed a new kind of air filtering material that uses natural, purified soy protein and bacterial cellulose – an organic compound produced by bacteria. The soy protein and cellulose are cost effective and already used in numerous applications, such as adhesives, plastic products, tissue regeneration materials and wound dressings.

Soy contains a large number of functional chemical groups – it includes 18 types of amino groups. Each of the chemical groups has the potential to capture passing pollution at the molecular level. The researchers used an acrylic acid treatment to disentangle the very rigid soy protein, so that the chemical groups can be more exposed to the pollutants.

The resulting filter was able to remove nearly all of the small particles as well as chemical pollutants, said Zhong.

Filters are economical, biodegradable

Especially in very polluted environments, people might be breathing an unknown mix of pollutants that could prove challenging to purify. But, with its large number of functional groups, the soy protein is able to attract a wide variety of polluting molecules.

“We can take advantage from those chemical groups to grab the toxics in the air,” Zhong said.

The materials are also cost-effective and biodegradable. Soybeans are among the most abundant plants in the world, she added.

Zhong occasionally visits her native China and has personally experienced the heavy pollution in Beijing as sunny skies turn to gray smog within a few days.

“Air pollution is a very serious health issue,” she said. “If we can improve indoor air quality, it would help a lot of people.”

Patents filed on filters, paper towels

In addition to the soy-based filters, the researchers have also developed gelatin- and cellulose-based air filters. They are also applying the filter material on top of low-cost and disposable paper towel to reinforce it and to improve its performance. They have filed patents on the technology and are interested in commercialization opportunities.

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

Soy protein isolate/bacterial cellulose composite membranes for high efficiency particulate air filtration by Xiaobing Liu, Hamid Souzandeh, Yudong Zheng, Yajie Xie, Wei-Hong Zhong, Cai Wang. Composites Science and Technology Volume 138, 18 January 2017, Pages 124–133         http://dx.doi.org/10.1016/j.compscitech.2016.11.022

This paper is behind a paywall.

Prawn (shrimp) shopping bags and saving the earth

Using a material (shrimp shells) that is disposed of as waste to create a biodegradable product (shopping bags) can only be described as a major win. A Jan. 10, 2017 news item on Nanowerk makes the announcement,

Bioengineers at The University of Nottingham are trialling how to use shrimp shells to make biodegradable shopping bags, as a ‘green’ alternative to oil-based plastic, and as a new food packaging material to extend product shelf life.

The new material for these affordable ‘eco-friendly’ bags is being optimised for Egyptian conditions, as effective waste management is one of the country’s biggest challenges.

An expert in testing the properties of materials, Dr Nicola Everitt from the Faculty of Engineering at Nottingham, is leading the research together with academics at Nile University in Egypt.

“Non-degradable plastic packaging is causing environmental and public health problems in Egypt, including contamination of water supplies which particularly affects living conditions of the poor,” explains Dr Everitt.

Natural biopolymer products made from plant materials are a ‘green’ alternative growing in popularity, but with competition for land with food crops, it is not a viable solution in Egypt.

A Jan. 10, 2017 University of Nottingham press release, which originated the news item,expands on the theme,

This new project aims to turn shrimp shells, which are a part of the country’s waste problem into part of the solution.

Dr Everitt said: “Use of a degradable biopolymer made of prawn shells for carrier bags would lead to lower carbon emissions and reduce food and packaging waste accumulating in the streets or at illegal dump sites. It could also make exports more acceptable to a foreign market within a 10-15-year time frame. All priorities at a national level in Egypt.”

Degradable nanocomposite material

The research is being undertaken to produce an innovative biopolymer nanocomposite material which is degradable, affordable and suitable for shopping bags and food packaging.

Chitosan is a man-made polymer derived from the organic compound chitin, which is extracted from shrimp shells, first using acid (to remove the calcium carbonate “backbone” of the crustacean shell) and then alkali (to produce the long molecular chains which make up the biopolymer).

The dried chitosan flakes can then be dissolved into solution and polymer film made by conventional processing techniques.

Chitosan was chosen because it is a promising biodegradable polymer already used in pharmaceutical packaging due to its antimicrobial, antibacterial and biocompatible properties. The second strand of the project is to develop an active polymer film that absorbs oxygen.

Enhancing food shelf life and cutting food waste

This future generation food packaging could have the ability to enhance food shelf life with high efficiency and low energy consumption, making a positive impact on food wastage in many countries.

If successful, Dr Everitt plans to approach UK packaging manufacturers with the product.

Additionally, the research aims to identify a production route by which these degradable biopolymer materials for shopping bags and food packaging could be manufactured.

I also found the funding for this project to be of interest (from the press release),

The project is sponsored by the Newton Fund and the Newton-Mosharafa Fund grant and is one of 13 Newton-funded collaborations for The University of Nottingham.

The collaborations, which are designed to tackle community issues through science and innovation, with links formed with countries such as Brazil, Egypt, Philippines and Indonesia.

Since the Newton Fund was established in 2014, the University has been awarded a total of £4.5m in funding. It also boasts the highest number of institutional-led collaborations.

Professor Nick Miles Pro-Vice-Chancellor for Global Engagement said: “The University of Nottingham has a long and established record in global collaboration and research.

The Newton Fund plays to these strengths and enables us to work with institutions around the world to solve some of the most pressing issues facing communities.”

From a total of 68 universities, The University of Nottingham has emerged as the top awardee of British Council Newton Fund Institutional Links grants (13) and is joint top awardee from a total of 160 institutions competing for British Council Newton Fund Researcher Links Workshop awards (6).

Professor Miles added: “This is testament to the incredible research taking place across the University – both here in the UK and in the campuses in Malaysia and China – and underlines the strength of our research partnerships around the world.”

That’s it!

Are there any leaders in the ‘graphene race’?

Tom Eldridge, a director and co-founder of Fullerex, has written a Jan. 5, 2017 essay titled: Is China still leading the graphene race? for Nanotechnology Now. Before getting to the essay, here’s a bit more about Fullerex and Tom Eldridge’s qualifications. From Fullerex’s LinkedIn description,

Fullerex is a leading independent broker of nanomaterials and nano-intermediates. Our mission is to support the advancement of nanotechnology in creating radical, transformative and sustainable improvement to society. We are dedicated to achieving these aims by accelerating the commercialisation and usage of nanomaterials across industry and beyond. Fullerex is active in market development and physical trading of advanced materials. We generate demand for nanomaterials across synergistic markets by stimulating innovation with end-users and ensuring robust supply chains are in place to address the growing commercial trade interest. Our end-user markets include Polymers and Polymer Composites, Coatings, Tyre and Rubber, Cementitious Composites, 3D Printing and Printed Electronics, the Energy sector, Lubricating Oils and Functional Fluids. The materials we cover: Nanomaterials: Includes fullerenes, carbon nanotubes and graphene, metal and metal oxide nanoparticles, and organic-inorganic hybrids. Supplied as raw nanopowders or ready-to-use dispersions and concentrates. Nano-intermediates: Producer goods and semi-finished products such as nano-enabled coatings, polymer masterbatches, conductive inks, thermal interface materials and catalysts.

As for Tom Eldridge, here’s more about him, his brother, and the company from the Fullerex About page,

Fullerex was founded by Joe and Tom Eldridge, brothers with a keen interest in nanotechnology and the associated emerging market for nanomaterials.

Joe has a strong background in trading with nearly 10 years’ experience as a stockbroker, managing client accounts for European Equities and FX. At University he read Mathematics at Imperial College London gaining a BSc degree and has closely followed the markets for disruptive technologies and advanced materials for a number of years.

Tom worked in the City of London for 7 years in commercial roles throughout his professional career, with an expertise in market data, financial and regulatory news. In his academic background, he earned a BSc degree in Physics and Philosophy at Kings College London and is a member of the Institute of Physics.

As a result, Fullerex has the strong management composition that allows the company to support the growth of the nascent and highly promising nanomaterials industry. Fullerex is a flexible company with drive, enthusiasm and experience, committed to aiding the development of this market.

Getting back to the matter at hand, that’s a rather provocative title for Tom Eldridge’s essay,. given that he’s a Brit and (I believe) the Brits viewed themselves as leaders in the ‘graphene race’ but he offers a more nuanced analysis than might be expected from the title. First, the patent landscape (from Eldridge’s Jan. 5, 2017 essay),

As competition to exploit the “wonder material” has intensified around the world, detailed reports have so far been published which set out an in-depth depiction of the global patent landscape for graphene, notably from CambridgeIP and the UK Intellectual Property Office, in 2013 and 2015 respectively. Ostensibly the number of patents and patent applications both indicated that China was leading the innovation in graphene technology. However, on closer inspection it became less clear as to how closely the patent figures themselves reflect actual progress and whether this will translate into real economic impact. Some of the main reasons to be doubtful included:

– 98% of the Chinese patent applications only cover China, so therefore have no worldwide monopoly.
– A large number of the Chinese patents are filed in December, possibly due to demand to meet patent quotas. The implication being that the patent filings follow a politically driven agenda, rather than a purely innovation or commercially driven agenda.
– In general, inventors could be more likely to file for patent protection in some countries rather than others e.g. for tax purposes. Which therefore does not give a truly accurate picture of where all the actual research activity is based.
– Measuring the proportion of graphene related patents to overall patents is more indicative of graphene specialisation, which shows that Singapore has the largest proportion of graphene patents, followed by China, then South Korea.

(Intellectual Property Office, 2015), (Ellis, 2015), (CambridgeIP, 2013)

Then, there’s the question of production,

Following the recent launch of the latest edition of the Bulk Graphene Pricing Report, which is available exclusively through The Graphene Council, Fullerex has updated its comprehensive list of graphene producers worldwide, and below is a summary of the number of graphene producers by country in 2017.

Summary Table Showing the Number of Graphene Producers by Country and Region

The total number of graphene producers identified is 142, across 27 countries. This research expands upon previous surveys of the graphene industry, such as the big data analysis performed by Nesta in 2015 (Shapira, 2015). The study by Nesta [formerly  NESTA, National Endowment for Science, Technology and the Arts) is an independent charity that works to increase the innovation capacity of the UK; see Wikipedia here for more about NESTA] revealed 65 producers throughout 16 countries but was unable to glean accurate data on producers in Asia, particularly China.

As we can now see however from the data collected by Fullerex, China has the largest number of graphene producers, followed by the USA, and then the UK.

In addition to having more companies active in the production and sale of graphene than any other country, China also holds about 2/3rds of the global production capacity, according to Fullerex.

Eldridge goes on to note that the ‘graphene industry’ won’t truly grow and develop until there are substantive applications for the material. He also suggests taking another look at the production figures,

As with the patent landscape, rather than looking at the absolute figures, we can review the numbers in relative terms. For instance, if we normalise to account for the differences in the size of each country, by looking at the number of producers as a proportion of GDP, we see the following: Spain (7.18), UK (4.48), India (3.73), China (3.57), Canada (3.28) [emphasis mine], USA (1.79) (United Nations, 2013).

Unsurprisingly, each leading country has a national strategy for economic development which involves graphene prominently.

For instance, The Spanish Council for Scientific Research has lent 9 of its institutes along with 10 universities and other public R&D labs involved in coordinating graphene projects with industry.

The Natural Sciences and Engineering Research Council of Canada [NSERC] has placed graphene as one of five research topics in its target area of “Advanced Manufacturing” for Strategic Partnership Grants.

The UK government highlights advanced materials as one of its Eight Great Technologies, within which graphene is a major part of, having received investment for the NGI and GEIC buildings, along with EPSRC and Innovate UK projects. I wrote previously about the UK punching above its weight in terms of research, ( http://fullerex.com/index.php/articles/130-the-uk-needs-an-industrial-revolution-can-graphene-deliver/ ) but that R&D spending relative to GDP was too low compared to other developed nations. It is good to see that investment into graphene production in the UK is bucking that trend, and we should anticipate this will provide a positive economic outcome.

Yes, I’m  particularly interested in the fact Canada becomes more important as a producer when the numbers are relative but it is interesting to compare the chart with Eldridge’s text and to note how importance shifts depending on what numbers are being considered.

I recommend reading Eldridge’s piece in its entirety.

A few notes about graphene in Canada

By the way, the information in Eldridge’s essay about NSERC’s placement of graphene as a target area for grants is news to me. (As I have often noted here, I get more information about the Canadian nano scene from international sources than I do from our national sources.)

Happily I do get some home news such as a Jan. 5, 2017 email update from Lomiko Metals, a Canadian junior exploration company focused on graphite and lithium. The email provides the latest information from the company (as I’m not an expert in business or mining this is not an endorsement),

On December 13, 2016 we were excited to announce the completion of our drill program at the La Loutre flake graphite property. We received very positive results from our 1550 meter drilling program in 2015 in the area we are drilling now. In that release I stated, “”The intercepts of multiple zones of mineralization in the Refractory Zone where we have reported high grade intercepts previously is a very promising sign. The samples have been rushed to the ALS Laboratory for full assay testing,” We hope to have the results of those assays shortly.

December 16, 2016 Lomiko announced a 10:1 roll back of our shares. We believe that this roll back is important as we work towards securing long term equity financing for the company. Lomiko began trading on the basis of the roll back on December 19.

We believe that Graphite has a bright future because of the many new products that will rely on the material. I have attached a link to a video on Lomiko, Graphite and Graphene.  


January 3, 2017 Lomiko announced the extension and modification of its option agreements with Canadian Strategic Metals Inc. for the La Loutre and Lac des Iles properties. The effect of this extension is to give Lomiko additional time to complete the required work under the agreements.

Going forward Lomiko is in a much stronger position as the result of our share roll back. Potential equity funders who are very interested in our forthcoming assay results from La Loutre and the overall prospects of the company, have been reassured by our share consolidation.

Looking forward to 2017, we anticipate the assays of the La Loutre drilling to be delivered in the next 90 days, sooner we hope. We also anticipate additional equity funding will become available for the further exploration and delineation of the La Loutre and Lac des Iles properties and deposits.

More generally, we are confident that the market for large flake graphite will become firmer in 2017. Lomiko’s strategy of identifying near surface, ready to mine, graphite nodes puts us in the position to take advantage of improvements in the graphite price without having to commit large sums to massive mine development. As we identify and analyze the graphite nodes we are finding we increase the potential resources of the company. 2017 should see significantly improved resource estimates for Lomiko’s properties.

As I wasn’t familiar with the term ‘roll back of shares’, I looked it up and found this in an April 18, 2012 posting by Dudley Pierce Baker on kitco.com,

As a general rule, we hate to see an announcement of a share rollback, however, there exceptions which we cover below. Investors should always be aware that if a company has, say over 150 million shares outstanding, in our opinion, it is a potential candidate for a rollback and the announcement should not come as a surprise.

Weak markets, a low share price, a large number of shares outstanding, little or no cash and you have a company which is an idea candidate for a rollback.

The basic concept of a rollback or consolidation in a company’s shares is rather simple.

We are witnessing a few cases of rollbacks not with the purpose of raising more money but rather to facilitate the listing of the company’s shares on the NYSE [New York Stock Exchange] Amex.

I have no idea what situation Lomiko finds itself in but it should be noted that graphere research has been active since 2004 when the first graphene sheets were extracted from graphite. This is a relatively new field of endeavour and Lomiko (along with other companies) is in the position of pioneering the effort here in Canada. That said, there are many competitors to graphene and major international race to commercialize nanotechnology-enabled products.

Are there any leaders in the ‘graphene race?

Getting back to the question in the headline, I don’t think there are any leaders at the moment. No one seems to have what they used to call “a killer app,” that one application/product that everyone wants and which drive demand for graphene.

Sniffing out disease (Na-Nose)

The ‘artificial nose’ is not a newcomer to this blog. The most recent post prior to this is a March 15, 2016 piece about Disney using an artificial nose for art conservation. Today’s (Jan. 9, 2016) piece concerns itself with work from Israel and ‘sniffing out’ disease, according to a Dec. 30, 2016 news item in Sputnik News,

A team from the Israel Institute of Technology has developed a device that from a single breath can identify diseases such as multiple forms of cancer, Parkinson’s disease, and multiple sclerosis. While the machine is still in the experimental stages, it has a high degree of promise for use in non-invasive diagnoses of serious illnesses.

The international team demonstrated that a medical theory first proposed by the Greek physician Hippocrates some 2400 years ago is true, certain diseases leave a “breathprint” on the exhalations of those afflicted. The researchers created a prototype for a machine that can pick up on those diseases using the outgoing breath of a patient. The machine, called the Na-Nose, tests breath samples for the presence of trace amounts of chemicals that are indicative of 17 different illnesses.

A Dec. 22, 2016 Technion Israel Institute of Technology press release offers more detail about the work,

An international team of 56 researchers in five countries has confirmed a hypothesis first proposed by the ancient Greeks – that different diseases are characterized by different “chemical signatures” identifiable in breath samples. …

Diagnostic techniques based on breath samples have been demonstrated in the past, but until now, there has not been scientific proof of the hypothesis that different and unrelated diseases are characterized by distinct chemical breath signatures. And technologies developed to date for this type of diagnosis have been limited to detecting a small number of clinical disorders, without differentiation between unrelated diseases.

The study of more than 1,400 patients included 17 different and unrelated diseases: lung cancer, colorectal cancer, head and neck cancer, ovarian cancer, bladder cancer, prostate cancer, kidney cancer, stomach cancer, Crohn’s disease, ulcerative colitis, irritable bowel syndrome, Parkinson’s disease (two types), multiple sclerosis, pulmonary hypertension, preeclampsia and chronic kidney disease. Samples were collected between January 2011 and June 2014 from in 14 departments at 9 medical centers in 5 countries: Israel, France, the USA, Latvia and China.

The researchers tested the chemical composition of the breath samples using an accepted analytical method (mass spectrometry), which enabled accurate quantitative detection of the chemical compounds they contained. 13 chemical components were identified, in different compositions, in all 17 of the diseases.

According to Prof. Haick, “each of these diseases is characterized by a unique fingerprint, meaning a different composition of these 13 chemical components.  Just as each of us has a unique fingerprint that distinguishes us from others, each disease has a chemical signature that distinguishes it from other diseases and from a normal state of health. These odor signatures are what enables us to identify the diseases using the technology that we developed.”

With a new technology called “artificially intelligent nanoarray,” developed by Prof. Haick, the researchers were able to corroborate the clinical efficacy of the diagnostic technology. The array enables fast and inexpensive diagnosis and classification of diseases, based on “smelling” the patient’s breath, and using artificial intelligence to analyze the data obtained from the sensors. Some of the sensors are based on layers of gold nanoscale particles and others contain a random network of carbon nanotubes coated with an organic layer for sensing and identification purposes.

The study also assessed the efficiency of the artificially intelligent nanoarray in detecting and classifying various diseases using breath signatures. To verify the reliability of the system, the team also examined the effect of various factors (such as gender, age, smoking habits and geographic location) on the sample composition, and found their effect to be negligible, and without impairment on the array’s sensitivity.

“Each of the sensors responds to a wide range of exhalation components,” explain Prof. Haick and his previous Ph.D student, Dr. Morad Nakhleh, “and integration of the information provides detailed data about the unique breath signatures characteristic of the various diseases. Our system has detected and classified various diseases with an average accuracy of 86%.

This is a new and promising direction for diagnosis and classification of diseases, which is characterized not only by considerable accuracy but also by low cost, low electricity consumption, miniaturization, comfort and the possibility of repeating the test easily.”

“Breath is an excellent raw material for diagnosis,” said Prof. Haick. “It is available without the need for invasive and unpleasant procedures, it’s not dangerous, and you can sample it again and again if necessary.”

Here’s a schematic of the study, which the researchers have made available,

Diagram: A schematic view of the study. Two breath samples were taken from each subject, one was sent for chemical mapping using mass spectrometry, and the other was analyzed in the new system, which produced a clinical diagnosis based on the chemical fingerprint of the breath sample. Courtesy: Tech;nion

There is also a video, which covers much of the same ground as the press release but also includes information about the possible use of the Na-Nose technology in the European Union’s SniffPhone project,

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

Diagnosis and Classification of 17 Diseases from 1404 Subjects via Pattern Analysis of Exhaled Molecules by Morad K. Nakhleh, Haitham Amal, Raneen Jeries, Yoav Y. Broza, Manal Aboud, Alaa Gharra, Hodaya Ivgi, Salam Khatib, Shifaa Badarneh, Lior Har-Shai, Lea Glass-Marmor, Izabella Lejbkowicz, Ariel Miller, Samih Badarny, Raz Winer, John Finberg, Sylvia Cohen-Kaminsky, Frédéric Perros, David Montani, Barbara Girerd, Gilles Garcia, Gérald Simonneau, Farid Nakhoul, Shira Baram, Raed Salim, Marwan Hakim, Maayan Gruber, Ohad Ronen, Tal Marshak, Ilana Doweck, Ofer Nativ, Zaher Bahouth, Da-you Shi, Wei Zhang, Qing-ling Hua, Yue-yin Pan, Li Tao, Hu Liu, Amir Karban, Eduard Koifman, Tova Rainis, Roberts Skapars, Armands Sivins, Guntis Ancans, Inta Liepniece-Karele, Ilze Kikuste, Ieva Lasina, Ivars Tolmanis, Douglas Johnson, Stuart Z. Millstone, Jennifer Fulton, John W. Wells, Larry H. Wilf, Marc Humbert, Marcis Leja, Nir Peled, and Hossam Haick. ACS Nano, Article ASAP DOI: 10.1021/acsnano.6b04930 Publication Date (Web): December 21, 2016

Copyright © 2017 American Chemical Society

This paper appears to be open access.

As for SniffPhone, they’re hoping that Na-Nose or something like it will allow them to modify smartphones in a way that will allow diseases to be detected.

I can’t help wondering who will own the data if your smartphone detects a disease. If you think that’s an idle question, here’s an excerpt from Sue Halpern’s Dec. 22, 2016 review of two books (“Weapons of Math Destruction: How Big Data Increases Inequality and Threatens Democracy” by Cathy O’Neil and “Virtual Competition: The Promise and Perils of the Algorithm-Driven Economy” by Ariel Ezrachi and Maurice E. Stucke) for the New York Times Review of Books,

We give our data away. We give it away in drips and drops, not thinking that data brokers will collect it and sell it, let alone that it will be used against us. There are now private, unregulated DNA databases culled, in part, from DNA samples people supply to genealogical websites in pursuit of their ancestry. These samples are available online to be compared with crime scene DNA without a warrant or court order. (Police are also amassing their own DNA databases by swabbing cheeks during routine stops.) In the estimation of the Electronic Frontier Foundation, this will make it more likely that people will be implicated in crimes they did not commit.

Or consider the data from fitness trackers, like Fitbit. As reported in The Intercept:

During a 2013 FTC panel on “Connected Health and Fitness,” University of Colorado law professor Scott Peppet said, “I can paint an incredibly detailed and rich picture of who you are based on your Fitbit data,” adding, “That data is so high quality that I can do things like price insurance premiums or I could probably evaluate your credit score incredibly accurately.”

Halpern’s piece is well worth reading in its entirety.

Soft contact lenses key to supercapacitor breaththrough

It seems like pretty exciting news for anyone following the supercapacitor story but they are being awfully cagey about it all in a Dec. 6, 2016 news item on Nanowerk,

Ground-breaking research from the University of Surrey and Augmented Optics Ltd., in collaboration with the University of Bristol, has developed potentially transformational technology which could revolutionise the capabilities of appliances that have previously relied on battery power to work.

This development by Augmented Optics Ltd., could translate into very high energy density super-capacitors making it possible to recharge your mobile phone, laptop or other mobile devices in just a few seconds.

The technology could have a seismic impact across a number of industries, including transport, aerospace, energy generation, and household applications such as mobile phones, flat screen electronic devices, and biosensors. It could also revolutionise electric cars, allowing the possibility for them to recharge as quickly as it takes for a regular non-electric car to refuel with petrol – a process that currently takes approximately 6-8 hours to recharge. Imagine, instead of an electric car being limited to a drive from London to Brighton, the new technology could allow the electric car to travel from London to Edinburgh without the need to recharge, but when it did recharge for this operation to take just a few minutes to perform.

I imagine the reason for the caginess has to do with the efforts to commercialize the technology. In any event, here’s a little more from a Dec. 5, 2016 University of Surrey press release by Ashley Lovell,

Supercapacitor buses are already being used in China, but they have a very limited range whereas this technology could allow them to travel a lot further between recharges. Instead of recharging every 2-3 stops this technology could mean they only need to recharge every 20-30 stops and that will only take a few seconds.

Elon Musk, of Tesla and SpaceX, has previously stated his belief that supercapacitors are likely to be the technology for future electric air transportation. We believe that the present scientific advance could make that vision a reality.

The technology was adapted from the principles used to make soft contact lenses, which Dr Donald Highgate (of Augmented Optics, and an alumnus of the University of Surrey) developed following his postgraduate studies at Surrey 40 years ago. Supercapacitors, an alternative power source to batteries, store energy using electrodes and electrolytes and both charge and deliver energy quickly, unlike conventional batteries which do so in a much slower, more sustained way. Supercapacitors have the ability to charge and discharge rapidly over very large numbers of cycles. However, because of their poor energy density per kilogramme (approximately just one twentieth of existing battery technology), they have, until now, been unable to compete with conventional battery energy storage in many applications.

Dr Brendan Howlin of the University of Surrey, explained: “There is a global search for new energy storage technology and this new ultra capacity supercapacitor has the potential to open the door to unimaginably exciting developments.”

The ground-breaking research programme was conducted by researchers at the University of Surrey’s Department of Chemistry where the project was initiated by Dr Donald Highgate of Augmented Optics Ltd. The research team was co-led by the Principal Investigators Dr Ian Hamerton and Dr Brendan Howlin. Dr Hamerton continues to collaborate on the project in his new post at the University of Bristol, where the electrochemical testing to trial the research findings was carried out by fellow University of Bristol academic – David Fermin, Professor of Electrochemistry in the School of Chemistry.

Dr Ian Hamerton, Reader in Polymers and Composite Materials from the Department of Aerospace Engineering, University of Bristol said: “While this research has potentially opened the route to very high density supercapacitors, these *polymers have many other possible uses in which tough, flexible conducting materials are desirable, including bioelectronics, sensors, wearable electronics, and advanced optics. We believe that this is an extremely exciting and potentially game changing development.”

*the materials are based on large organic molecules composed of many repeated sub-units and bonded together to form a 3-dimensional network.

Jim Heathcote, Chief Executive of both Augmented Optics Ltd and Supercapacitor Materials Ltd, said: “It is a privilege to work with the teams from the University of Surrey and the University of Bristol. The test results from the new polymers suggest that extremely high energy density supercapacitors could be constructed in the very new future. We are now actively seeking commercial partners [emphasis mine] in order to supply our polymers and offer assistance to build these ultra high energy density storage devices.”

I was not able to find a website for Augmented Optics but there is one for SuperCapacitor Materials here.

Creeping gel does ‘The Loco-Motion’

Now it’s the creeping gel’s turn, from an Oct. 24, 2016 news item on phys.org,

Directed motion seems simple to us, but the coordinated interplay of complex processes is needed, even for seemingly simple crawling motions of worms or snails. By using a gel that periodically swells and shrinks, researchers developed a model for the waves of muscular contraction and relaxation involved in crawling. As reported in the journal Angewandte Chemie, they were able to produce two types of crawling motion by using inhomogeneous irradiation.


Courtesy: Angewandte Chemie

Courtesy: Angewandte Chemie

An Oct. 24, 2016 Angewandte Chemie (Wiley) press release (also on EurekAlert), which originated the news item, explains further,

Crawling comes from waves that travel through muscle. These waves can travel in the same direction as the animal is crawling (direct waves), from the tail end toward the head, or in the opposite direction (retrograde waves), from the head toward the tail. While land snails use the former type of wave, earthworms and limpets use the latter. Chitons (polyplacophora) can switch between both types of movement.

With the aid of a chemical model in the form of a self-oscillating gel, researchers working with Qingyu Gao at the China University of Mining and Technology (Jiangsu, China) and Irving R. Epstein at Brandeis University (Waltham, Massachusetts, USA) have been able to answer some of the many questions about these crawling processes.

A gel is a molecular network with liquid bound in the gaps. In this case, the liquid contains all of the ingredients needed for an oscillating chemical reaction (“chemical clock”). The researchers incorporated one component of their reaction system into the network: a ruthenium complex. During the reaction, the ruthenium periodically switches between two oxidation states, Ru2+ and Ru3+. This switch changes the gel so that in one state it can hold more liquid than the other, so the gel swells and shrinks periodically. Like the chemical clock, these regions propagate in waves, similar to the waves of muscle contractions in crawling.

The complex used in this gel also changes oxidation state when irradiated with light. When the right half of the gel is irradiated more strongly than the left, the waves move from right to left, i.e., from a high- to a low-frequency region of gel oscillations. Once the difference in intensity of irradiation reaches a certain threshold, it causes a wormlike motion of the gel from left to right, retrograde wave locomotion. If the difference is increased further, the gel comes to a stop. A further increase in the difference causes the gel to move again, but in the opposite direction, i.e., direct wave locomotion. The nonuniform illumination plays a role analogous to that of anchoring segments and appendages (such as limbs and wings) during cell migration and animal locomotion, which control the direction of locomotion by strengthening direct movement and/or inhibiting the opposite movement.

By using computational models, the researchers were able to describe these processes. Within the gel, there are regions where pulling forces predominate; pushing forces predominate in other areas. Variations in the intensity of the irradiation lead to different changes in the friction forces and the tensions in the gel. When these effects are added up, it is possible to predict in which direction a particular grid element of the gel will move.

One important finding from this model: special changes in the viscoelastic properties of the slime excreted by the snails and worms as they crawl are not required for locomotion, whether retrograde or direct.

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

Retrograde and Direct Wave Locomotion in a Photosensitive Self-Oscillating Gel by Lin Ren, Weibing She, Prof. Dr. Qingyu Gao, Dr. Changwei Pan, Dr. Chen Ji, and Prof. Dr. Irving R. Epstein. Angewandte Chemie International Edition DOI: 10.1002/anie.201608367 Version of Record online: 13 OCT 2016

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

This paper is behind a paywall.

For anyone curious about the song, there’s this from its Wikipedia entry (Note: Links have been removed),

“The Loco-Motion” is a 1962 pop song written by American songwriters Gerry Goffin and Carole King. “The Loco-Motion” was originally written for Dee Dee Sharp but Sharp turned the song down.[1] The song is notable for appearing in the American Top 5 three times – each time in a different decade, performed by artists from three different cultures: originally African American pop singer Little Eva in 1962 (U.S. No. 1);[2] then American band Grand Funk Railroad in 1974 (U.S. No. 1);[3] and finally Australian singer Kylie Minogue in 1988 (U.S. No. 3).[4]

The song is a popular and enduring example of the dance-song genre: much of the lyrics are devoted to a description of the dance itself, usually done as a type of line dance. However, the song came before the dance.

“The Loco-Motion” was also the second song to reach No. 1 by two different musical acts. The earlier song to do this was “Go Away Little Girl”, also written by Goffin and King. It is one of only nine songs to achieve this

I had not realized this song had such a storied past; there’s a lot more about it in the Wikipedia entry.

The volatile lithium-ion battery

On the heels of Samsung’s Galaxy Note 7 recall due to fires (see Alex Fitzpatrick’s Sept. 9, 2016 article for Time magazine for a good description of lithium-ion batteries and why they catch fire; see my May 29, 2013 posting on lithium-ion batteries, fires [including the airplane fires], and nanotechnology risk assessments), there’s new research on lithium-ion batteries and fires from China. From an Oct. 21, 2016 news item on Nanotechnology Now,

Dozens of dangerous gases are produced by the batteries found in billions of consumer devices, like smartphones and tablets, according to a new study. The research, published in Nano Energy, identified more than 100 toxic gases released by lithium batteries, including carbon monoxide.

An Oct. 20, 2016 Elsevier Publishing press release (also on EurekAlert), which originated the news item, expands on the theme,

The gases are potentially fatal, they can cause strong irritations to the skin, eyes and nasal passages, and harm the wider environment. The researchers behind the study, from the Institute of NBC Defence and Tsinghua University in China, say many people may be unaware of the dangers of overheating, damaging or using a disreputable charger for their rechargeable devices.

In the new study, the researchers investigated a type of rechargeable battery, known as a “lithium-ion” battery, which is placed in two billion consumer devices every year.

“Nowadays, lithium-ion batteries are being actively promoted by many governments all over the world as a viable energy solution to power everything from electric vehicles to mobile devices. The lithium-ion battery is used by millions of families, so it is imperative that the general public understand the risks behind this energy source,” explained Dr. Jie Sun, lead author and professor at the Institute of NBC Defence.

The dangers of exploding batteries have led manufacturers to recall millions of devices: Dell recalled four million laptops in 2006 and millions of Samsung Galaxy Note 7 devices were recalled this month after reports of battery fires. But the threats posed by toxic gas emissions and the source of these emissions are not well understood.

Dr. Sun and her colleagues identified several factors that can cause an increase in the concentration of the toxic gases emitted. A fully charged battery will release more toxic gases than a battery with 50 percent charge, for example. The chemicals contained in the batteries and their capacity to release charge also affected the concentrations and types of toxic gases released.

Identifying the gases produced and the reasons for their emission gives manufacturers a better understanding of how to reduce toxic emissions and protect the wider public, as lithium-ion batteries are used in a wide range of environments.

“Such dangerous substances, in particular carbon monoxide, have the potential to cause serious harm within a short period of time if they leak inside a small, sealed environment, such as the interior of a car or an airplane compartment,” Dr. Sun said.

Almost 20,000 lithium-ion batteries were heated to the point of combustion in the study, causing most devices to explode and all to emit a range of toxic gases. Batteries can be exposed to such temperature extremes in the real world, for example, if the battery overheats or is damaged in some way.

The researchers now plan to develop this detection technique to improve the safety of lithium-ion batteries so they can be used to power the electric vehicles of the future safely.

“We hope this research will allow the lithium-ion battery industry and electric vehicle sector to continue to expand and develop with a greater understanding of the potential hazards and ways to combat these issues,” Sun concluded.

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

Toxicity, a serious concern of thermal runaway from commercial Li-ion battery by Jie Sun, Jigang Li, Tian Zhou, Kai Yang, Shouping Wei, Na Tang, Nannan Dang, Hong Li, Xinping Qiu, Liquan Chend. Nano Energy Volume 27, September 2016, Pages 313–319  http://dx.doi.org/10.1016/j.nanoen.2016.06.031

This paper appears to be open access.

Self-healing lithium-ion batteries for textiles

It’s easy to forget how hard we are on our textiles. We rip them, step on them, agitate them in water, splatter them with mud, and more. So, what happens when we integrate batteries and electronics into them? An Oct. 20, 2016 news item on phys.org describes one of the latest ‘textile batter technologies’,

Electronics that can be embedded in clothing are a growing trend. However, power sources remain a problem. In the journal Angewandte Chemie, scientists have now introduced thin, flexible, lithium ion batteries with self-healing properties that can be safely worn on the body. Even after completely breaking apart, the battery can grow back together without significant impact on its electrochemical properties.


© Wiley-VCH

An Oct. 20, 2016 Wiley Angewandte Chemie International Edition press release (also on EurekAlert), which originated the news item, describes some of the problems associated with lithium-ion batteries and this new technology designed to address them,

Existing lithium ion batteries for wearable electronics can be bent and rolled up without any problems, but can break when they are twisted too far or accidentally stepped on—which can happen often when being worn. This damage not only causes the battery to fail, it can also cause a safety problem: Flammable, toxic, or corrosive gases or liquids may leak out.

A team led by Yonggang Wang and Huisheng Peng has now developed a new family of lithium ion batteries that can overcome such accidents thanks to their amazing self-healing powers. In order for a complicated object like a battery to be made self-healing, all of its individual components must also be self-healing. The scientists from Fudan University (Shanghai, China), the Samsung Advanced Institute of Technology (South Korea), and the Samsung R&D Institute China, have now been able to accomplish this.

The electrodes in these batteries consist of layers of parallel carbon nanotubes. Between the layers, the scientists embedded the necessary lithium compounds in nanoparticle form (LiMn2O4 for one electrode, LiTi2(PO4)3 for the other). In contrast to conventional lithium ion batteries, the lithium compounds cannot leak out of the electrodes, either while in use or after a break. The thin layer electrodes are each fixed on a substrate of self-healing polymer. Between the electrodes is a novel, solvent-free electrolyte made from a cellulose-based gel with an aqueous lithium sulfate solution embedded in it. This gel electrolyte also serves as a separation layer between the electrodes.

After a break, it is only necessary to press the broken ends together for a few seconds for them to grow back together. Both the self-healing polymer and the carbon nanotubes “stick” back together perfectly. The parallel arrangement of the nanotubes allows them to come together much better than layers of disordered carbon nanotubes. The electrolyte also poses no problems. Whereas conventional electrolytes decompose immediately upon exposure to air, the new gel is stable. Free of organic solvents, it is neither flammable nor toxic, making it safe for this application.

The capacity and charging/discharging properties of a battery “armband” placed around a doll’s elbow were maintained, even after repeated break/self-healing cycles.

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

A Self-Healing Aqueous Lithium-Ion Battery by Yang Zhao, Ye Zhang, Hao Sun, Xiaoli Dong, Jingyu Cao, Lie Wang, Yifan Xu, Jing Ren, Yunil Hwang, Dr. In Hyuk Son, Dr. Xianliang Huang, Prof. Yonggang Wang, and Prof. Huisheng Peng. Angewandte Chemie International Edition DOI: 10.1002/anie.201607951 Version of Record online: 12 OCT 2016

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

This paper is behind a paywall.

Not enough silver nanoparticles in water supply to be harmful?

While the news of a low concentration of silver nanoparticles in the water supply seems good in the short term, one can’t help wondering what will happen as more of them end up in the our water. As for the news itself, here’s the announcement concerning a review of some 300 papers, from an Oct. 13, 2016 news item on Nanowerk,

Silver nanoparticles have a wide array of uses, one of which is to treat drinking water for harmful bacteria and viruses. But do silver nanoparticles also kill off potentially beneficial bacteria or cause other harmful effects to water-based ecosystems? A new paper from a team of University of Missouri College of Engineering researchers says that’s not the case.

An Oct. 12, 2016 University of Missouri news release (also on EurekAlert), which originated the news item, expands on the theme (Note: Links have been removed),

In their paper, “Governing factors affecting the impacts of silver nanoparticles on wastewater treatment,” recently published in Science of the Total Environment, Civil and Environmental Engineering Department doctoral students Chiqian Zhang and Shashikanth Gajaraj and Department Chair and Professor Zhiqiang Hu worked with Ping Li of the South China University of Technology to analyze the results of approximately 300 published works on the subject of silver nanoparticles and wastewater. What they found was while silver nanoparticles can have moderately or even significantly adverse effects in large concentrations, the amount of silver nanoparticles found in our wastewater at present isn’t harmful to humans or the ecosystem as a whole.

“If the concentration remains low, it’s not a serious problem,” Zhang said.

Silver nanoparticles are used in wastewater treatment and found increasingly in everyday products in order to combat bacteria. In terms of wastewater treatment, silver nanoparticles frequently react with sulfides in biosolids, vastly limiting their toxicity.

Zhang said many of the studies looked at high concentrations and added that if, over time, the concentration rose to much higher levels of several milligrams per liter or higher), toxicity could become a problem. But he explained that it would take decades or even longer potentially to get to that point.

“People evaluate the toxicity in a small-scale system,” he said. “But with water collection systems, much of the silver nanoparticles become silver sulfide and not be harmful.”

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

Governing factors affecting the impacts of silver nanoparticles on wastewater treatment by Chiqian Zhang, Zhiqiang Hu, Ping Li, Shashikanth Gajaraj. Science of The Total Environment http://dx.doi.org/10.1016/j.scitotenv.2016.07.145 Available online 16 August 2016

This study is behind a paywall.

For the curious, I have a Feb. 28, 2013 posting where I contrasted two silver nanoparticle studies one of which found little risk and the other which raised serious concerns. Scroll down about about 60% of the way for the ‘cautionary’ study.

Personally, I’m inclined to agree silver nanoparticles are not an immediate concern but since no one knows what the tipping point might be, now would be a good time to get serious about research, policies, and regulation.