Tag Archives: Norway

Gender gaps in science and how statistics prove and disprove the finding

A Feb. 17, 2015 Northwestern University news release by Hilary Hurd Anyaso (also on EurekAlert) features research suggesting that parity in the numbers of men and women students pursuing science degrees is being achieved,

Scholars from diverse fields have long proposed that interlocking factors such as cognitive abilities, discrimination and interests may cause more women than men to leave the science, technology, engineering and mathematics (STEM) pipeline after entering college.

Now a new Northwestern University analysis has poked holes in the much referenced “leaky pipeline” metaphor.

The research shows that the bachelor’s-to-Ph.D. pipeline in science and engineering fields no longer leaks more women than men as it did in the past

Curt Rice, a professor at Norway’s University of Tromsø, has challenged the findings in a Feb. 18, 2015 post on his eponymous website (more about that later).

The news release goes on to describe how the research was conducted and the conclusions researchers drew from the data,

The researchers used data from two large nationally representative research samples to reconstruct a 30-year portrait of how bachelor’s-to-Ph.D. persistence rates for men and women have changed in the United States since the 1970s. For this study, the term STEM persistence rate refers to the proportion of students who earned a Ph.D. in a particular STEM field (e.g. engineering) among students who had earlier received bachelor’s degrees in that same field.

They were particularly surprised that the gender persistence gap completely closed in pSTEM fields (physical science, technology, engineering and mathematics) — the fields in which women are most underrepresented.

Among students earning pSTEM bachelor’s degrees in the 1970s, men were 1.6 to 1.7 times as likely as women to later earn a pSTEM Ph.D. However, this gap completely closed by the 1990s.

Men still outnumber women by approximately three to one among pSTEM Ph.D. earners. But those differences in representation are not explained by differences in persistence from the bachelor’s to Ph.D. degree, said David Miller, an advanced doctoral student in psychology at Northwestern and lead author of the study.

“Our analysis shows that women are overcoming any potential gender biases that may exist in graduate school or undergraduate mentoring about pursing graduate school,” Miller said. “In fact, the percentage of women among pSTEM degree earners is now higher at the Ph.D. level than at the bachelor’s, 27 percent versus 25 percent.”

Jonathan Wai, a Duke University Talent Identification Program research scientist and co-author of the study, said a narrowing of gender gaps makes sense given increased efforts to promote gender diversity in science and engineering.

“But a complete closing of the gap was unexpected, especially given recent evidence of gender bias in science mentoring,” Wai said.

Consequently, the widely used leaky pipeline metaphor is a dated description of gender differences in postsecondary STEM education, Wai added.

Other research shows that gaps in persistence rates are also small to nonexistent past the Ph.D., Miller said.

“For instance, in physical science and engineering fields, male and female Ph.D. holders are equally likely to earn assistant professorships and academic tenure,” Miller said.

The leaky pipeline metaphor is inaccurate for nearly all postsecondary pathways in STEM, Miller said, with two important exceptions.

“The Ph.D.-to-assistant-professor pipeline leaks more women than men in life science and economics,” he said. “Differences in those fields are large and important.”

The implications of the research, Miller said, are important in guiding research, resources and strategies to explain and change gender imbalances in science.

“The leaking pipeline metaphor could potentially direct thought and resources away from other strategies that could more potently increase women’s representation in STEM,” he said.

For instance, plugging leaks in the pipeline from the beginning of college to the bachelor’s degree would fail to substantially increase women’s representation among U.S. undergraduates in the pSTEM fields, Miller said.

Of concern, women’s representation among pSTEM bachelor’s degrees has been decreasing during the past decade, Miller noted. “Our analyses indicate that women’s representation at the Ph.D. level is starting to follow suit by declining for the first time in over 40 years,” he said.

“This recent decline at the Ph.D. level could likely mean that women’s progress at the assistant professor level might also slow down or reverse in future years, so these trends will need to be watched closely,” Wai said.

While the researchers are encouraged that gender gaps in doctoral persistence have closed, they stressed that accurately assessing and changing gender biases in science should remain an important goal for educators and policy makers.

Before moving on to Rice’s comments, here’s a link to and citation for the paper,

The bachelor’s to Ph.D. STEM pipeline no longer leaks more women than men: a 30-year analysis by David I. Miller and Jonathan Wai. Front. Psychol., 17 February 2015, doi: 10.3389/fpsyg.2015.00037

This paper is open access (at least for now).

Maybe the situation isn’t improving after all

Curt Rice’s response titled, The incontinent pipeline: it’s not just women leaving higher education, suggests this latest research has unmasked a problem (Note: Links have been removed),

Freshly published research gives a more nuanced picture. The traditional recitation of percentages at various points along the pipeline provides a snapshot. The new research is more like a time-lapse film.

Unfortunately, the new study doesn’t actually show a pipeline being tightened up to leak less. Instead, it shows a pipeline that is leaking even more! The convergence in persistence rates for men and women is not a result of an increase in the rate of women taking a PhD; it’s the result of a decline in the rate of men doing so. It’s as though the holes have gotten bigger — they used to be so small that only women slipped through, but now men slide out, too.

Rice believes  that this improvement is ‘relative improvement’ i.e. the improvement exists in relation to declining numbers of men, a statistic that Rice gives more weight to than the Northwestern researchers appear to have done. ‘Absolute improvement’ would mean that numbers of women studying in the field had improved while men’s numbers had held steady or improved for them too.

To be fair, the authors of the paper seem to have taken at least some of this decline in men’s numbers into account (from the research paper),,

Reasons for the convergences in persistence rates remain unclear. Sometimes the convergence was driven by declines in men’s rates (e.g., in mathematics/computer science), increases in women’s rates (e.g., in physical science), or both (e.g., in engineering). help account for the changes in persistence rates. …

Overenthusiasm in the news release

Unfortunately, the headline and bullet list of highlights suggest a more ebullient research conclusion than seems warranted by the actual research results.

Think again about gender gap in science
Bachelor’s-to-Ph.D. pipeline in science, engineering no longer ‘leaks’ more women than men, new 30-year analysis finds

Research shows dated ‘leaky pipeline’ assumptions about gender imbalances in science

  • Men outnumber women as Ph.D. earners in science but no longer in doctoral persistence
  • Dramatic increase of women in science at Ph.D., assistant professorship levels since 1970s, but recent decline since 2010 may be of concern for future supply of female scientists
  • Assessing inaccurate assumptions key to correcting gender biases in science

Here’s the researchers’ conclusion,

Overall, these results and supporting literature point to the need to understand gender differences at the bachelor’s level and below to understand women’s representation in STEM at the Ph.D. level and above. Women’s representation in computer science, engineering, and physical science (pSTEM) fields has been decreasing at the bachelor’s level during the past decade. Our analyses indicate that women’s representation at the Ph.D. level is starting to follow suit by declining for the first time in over 40 years (Figure 2). This recent decline may also cause women’s gains at the assistant professor level and beyond to also slow down or reverse in the next few years. Fortunately, however, pathways for entering STEM are considerably diverse at the bachelor’s level and below. For instance, our prior research indicates that undergraduates who join STEM from a non-STEM field can substantially help the U.S. meet needs for more well-trained STEM graduates (Miller et al., under review). Addressing gender differences at the bachelor’s level could have potent effects at the Ph.D. level, especially now that women and men are equally likely to later earn STEM Ph.D.’s after the bachelor’s.

The conclusion seems to contradict the researchers’ statements in the news release,

“But a complete closing of the gap was unexpected, especially given recent evidence of gender bias in science mentoring,” Wai said.

Consequently, the widely used leaky pipeline metaphor is a dated description of gender differences in postsecondary STEM education, Wai added.

Other research shows that gaps in persistence rates are also small to nonexistent past the Ph.D., Miller said.

Incomplete pipeline

Getting back to Rice, he notes the pipeline in the Northwestern paper is incomplete (Note: Links have been removed),

In addition to the dubious celebration of the decline of persistence rates of men, the new research article also looks at an incomplete pipeline. In particular, it leaves aside the important issue of which PhD institutions students get into. For young researchers moving towards academic careers, we know that a few high-prestige universities are responsible for training future faculty members at nearly all other research universities. Are women and men getting into those high prestige universities in the same numbers? Or do women go to lower prestige institutions?

Following on that thought about lower prestige institutions and their impact on your career, there’s a Feb. 23, 2015 article by Joel Warner and Aaron Clauset in Slate investigating the situation, which applies to both men and women,

The United States prides itself on offering broad access to higher education, and thanks to merit-based admissions, ample financial aid, and emphasis on diverse student bodies, our country can claim some success in realizing this ideal.

The situation for aspiring professors is far grimmer. Aaron Clauset, a co-author of this article, is the lead author of a new study published in Science Advances that scrutinized more than 16,000 faculty members in the fields of business, computer science, and history at 242 schools. He and his colleagues found, as the paper puts it, a “steeply hierarchical structure that reflects profound social inequality.” The data revealed that just a quarter of all universities account for 71 to 86 percent of all tenure-track faculty in the U.S. and Canada in these three fields. Just 18 elite universities produce half of all computer science professors, 16 schools produce half of all business professors, and eight schools account for half of all history professors.

Then, Warner and Clauset said this about gender bias,

Here’s further evidence that the current system isn’t merely sorting the best of the best from the merely good. Female graduates of elite institutions tend to slip 15 percent further down the academic hierarchy than do men from the same institutions, evidence of gender bias to go along with the bias toward the top schools.

I suggest reading the Slate article, Rice’s post, and, if you have time, the Northwestern University research paper.

Coda: All about Curt Rice

Finally, this is for anyone who’s unfamiliar with Curt Rice (from the About page on his website; Note: Links have been removed),

In addition to my work as a professor at the University of Tromsø, I have three other roles that are closely related to the content on this website. I was elected by the permanent faculty to sit on the university board, I lead Norway’s Committee on Gender Balance and Diversity in Research, and I am the head of the Board for Current Research Information System in Norway (CRIStin). In all of these roles, I work to pursue my conviction that research and education are essential to improving society, and that making universities better therefore has the potential to make societies better.

I’m currently writing a book on gender balance. Why do men and women have different career paths? Why should we care? How can we start to make things better? Why is improving gender balance not only the right thing to do, but also the smart thing to do? For a taste of my approach, grab a copy of my free ebook on gender equality.

Beyond this book project, I use my speaking and writing engagements to reach audiences on the topics that excite me the most: gender balance, open access, leadership issues and more. These interests have grown during the past decade while I’ve had the privilege to occupy what were then two brand new leadership positions at the University of Tromsø.

From 2009–2013, I served as the elected Vice Rector for Research & Development (prorektor for forskning og utvikling). Before that, from 2002–2008, I was the founding director of my university’s first Norwegian Center of Excellence, the Center for Advanced Study in Theoretical Linguistics (CASTL). Given the luxury of being able to define those positions, I was able to pursue my passion for improving academic life by working to enhance conditions for education and research.

I’m part of the European Science Foundation’s genderSTE COST action (Gender, Science, Technology and Environment); I helped create the BALANSE program at the Research Council of Norway, which is designed to increase the numbers of women at the highest levels of research organizations. I am on the Advisory Board of the European Commission project EGERA (Effective Gender Equality in Research and Academia); I was on the Science Leaders Panel of the genSET project, in which we advised the European Commission about gender in science; I am a member of the Steering Committee for the Gender Summits.

I also led a national task force on research-based education that issued many suggestions for Norwegian institutions.

The quantum chemistry of nanomedicines

A Jan. 29, 2015 news item on Nanowerk provides an overview of the impact quantum chemical reactions may have on nanomedicines. Intriguingly, this line of query started with computations of white dwarf stars,

Quantum chemical calculations have been used to solve big mysteries in space. Soon the same calculations may be used to produce tomorrow’s cancer drugs.

Some years ago research scientists at the University of Oslo in Norway were able to show that the chemical bonding in the magnetic fields of small, compact stars, so-called white dwarf stars, is different from that on Earth. Their calculations pointed to a completely new bonding mechanism between two hydrogen atoms. The news attracted great attention in the media. The discovery, which in fact was made before astrophysicists themselves observed the first hydrogen molecules in white dwarf stars, was made by UiO’s Centre for Theoretical and Computational Chemistry. They based their work on accurate quantum chemical calculations of what happens when atoms and molecules are exposed to extreme conditions.

A Jan. 29, 2015 University of Oslo press release by Yngve Vogt, which originated the news item, offers a substantive description of molecules, electrons, and more for those of us whose last chemistry class is lost in the mists of time,

The research team is headed by Professor Trygve Helgaker, who for the last thirty years has taken the international lead on the design of a computer system for calculating quantum chemical reactions in molecules.

Quantum chemical calculations are needed to explain what happens to the electrons’ trajectories within a molecule.

Consider what happens when UV radiation sends energy-rich photons into your cells. This increases the energy level of the molecules. The outcome may well be that some of the molecules break up. This is exactly what happens when you sun-bathe.

“The extra energy will affect the behaviour of electrons and can destroy the chemical bonding within the molecule. This can only be explained by quantum chemistry. The quantum chemical models are used to produce a picture of the forces and tensions at play between the atoms and the electrons of a molecule, and of what is required for a molecule to dissociate,” says Trygve Helgaker.

The absurd world of the electrons

The quantum chemical calculations solve the Schrödinger equation for molecules. This equation is fundamental to all chemistry and describes the whereabouts of all electrons within a molecule. But here we need to pay attention, for things are really rather more complicated than that. Your high school physics teacher will have told you that electrons circle the atom. Things are not that simple, though, in the world of quantum physics. Electrons are not only particles, but waves as well. The electrons can be in many places at the same time. It’s impossible to keep track of their position. However, there is hope. Quantum chemical models describe the electrons’ statistical positions. In other words, they can establish the probable location of each electron.

The results of a quantum chemical calculation are often more accurate than what is achievable experimentally.

Among other things, the quantum chemical calculations can be used to predict chemical reactions. This means that the chemists will no longer have to rely on guesstimates in the lab. It is also possible to use quantum chemical calculations in order to understand what happens in experiments.

Enormous calculations

The calculations are very demanding.

“The Schrödinger equation is a highly complicated, partial differential equation, which cannot be accurately solved. Instead, we need to make do with heavy simulations”, says researcher Simen Kvaal.

The computations are so demanding that the scientists use one of the University’s fastest supercomputers.

“We are constantly stretching the boundaries of what is possible. We are restricted by the available machine capacity,” explains Helgaker.

Ten years ago it took two weeks to carry out the calculations for a molecule with 140 atoms. Now it can be done in two minutes.

“That’s 20,000 times faster than ten years ago. The computation process is now running 200 times faster because the computers have been doubling their speed every eighteen months. And the process is a further 100 times faster because the software has been undergoing constant improvement,” says senior engineer Simen Reine.

This year the research group has used 40 million CPU hours, of which twelve million were on the University’s supercomputer, which is fitted with ten thousand parallel processors. This allows ten thousand CPU hours to be over and done with in 60 minutes.

“We will always fill the computer’s free capacity. The higher the computational capacity, the bigger and more reliable the calculations.”

Thanks to ever faster computers, the quantum chemists are able to study ever larger molecules.

Today, it’s routine to carry out a quantum chemical calculation of what happens within a molecule of up to 400 atoms. By using simplified models it is possible to study molecules with several thousand atoms. This does, however, mean that some of the effects within the molecule are not being described in detail.

The researchers are now getting close to a level which enables them to study the quantum mechanics of living cells.

“This is exciting. The molecules of living cells may contain many hundred thousand atoms, but there is no need to describe the entire molecule using quantum mechanical principles. Consequently, we are already at a stage when we can help solve biological problems.”

There’s more from the press release which describes how this work could be applied in the future,

Hunting for the electrons of the insulin molecule

The chemists are thus able to combine sophisticated models with simpler ones. “This will always be a matter of what level of precision and detail you require. The optimal approach would have been to use the Schrödinger equation for everything.”

By way of compromise they can give a detailed description of every electron in some parts of the model, while in other parts they are only looking at average numbers.

Simen Reine has been using the team’s computer program, while working with Aarhus University [Finland], on a study of the insulin molecule. An insulin molecule consists of 782 atoms and 3,500 electrons.

“All electrons repel each other, while at the same time being pulled towards the atomic nuclei. The nuclei also repel each other. Nevertheless, the molecule remains stable. In order to study a molecule to a high level of precision, we therefore need to consider how all of the electrons move relative to one another. Such calculations are referred to as correlated and are very reliable.”

A complete correlated calculation of the insulin molecule takes nearly half a million CPU hours. If they were given the opportunity to run the program on the entire University’s supercomputer, the calculations would theoretically take two days.

“In ten years, we’ll be able to make these calculations in two minutes.”

Medically important

“Quantum chemical calculations can help describe phenomena at a level that may be difficult to access experimentally, but may also provide support for interpreting and planning experiments. Today, the calculations will be put to best use within the fields of molecular biology and biochemistry,” says Knut Fægri [vice-rector at the University of Oslo].

“Quantum chemistry is a fundamental theory which is important for explaining molecular events, which is why it is essential to our understanding of biological systems,” says [Associate Professor] Michele Cascella.

By way of an example, he refers to the analysis of enzymes. Enzymes are molecular catalysts that boost the chemical reactions within our cells.

Cascella also points to nanomedicines, which are drugs tasked with distributing medicine round our bodies in a much more accurate fashion.

“In nanomedicine we need to understand physical phenomena on a nano scale, forming as correct a picture as possible of molecular phenomena. In this context, quantum chemical calculations are important,” explains Michele Cascella.

Proteins and enzymes

Professor K. Kristoffer Andersson at the Department of Biosciences uses the simpler form of quantum chemical calculations to study the details of protein structures and the chemical atomic and electronic functions of enzymes.

“It is important to understand the chemical reaction mechanism, and how enzymes and proteins work. Quantum chemical calculations will teach us more about how proteins go about their tasks, step by step. We can also use the calculations to look at activation energy, i.e. how much energy is required to reach a certain state. It is therefore important to understand the chemical reaction patterns in biological molecules in order to develop new drugs,” says Andersson.

His research will also be useful in the search for cancer drugs. He studies radicals, which may be important to cancer. Among other things, he is looking at the metal ions function in proteins. These are ions with a large number of protons, neutrons and electrons.

Photosynthesis

Professor Einar Uggerud at the Department of Chemistry has uncovered an entirely new form of chemical bonding through sophisticated experiments and quantum chemical calculations.

Working with research fellow Glenn Miller, Professor Uggerud has found an unusually fragile key molecule, in a kite-shaped structure, consisting of magnesium, carbon and oxygen. The molecule may provide a new understanding of photosynthesis. Photosynthesis, which forms the basis for all life, converts CO2 into sugar molecules.

The molecule reacts so fast with water and other molecules that it has only been possible to study in isolation from other molecules, in a vacuum chamber.

“Time will tell whether the molecule really has an important connection with photosynthesis,” says Einar Uggerud.

I’m delighted with this explanation as it corrects my understanding of chemical bonds and helps me to better understand computational chemistry. Thank you University of Oslo and Yngve Vogt.

Finally, here’s a representation of an insulin molecule as understood by quantum computation,

QuantumInsulinMolecule

INSULIN: Working with Aarhus University, Simen Reine has calculated the tensions between the electrons and atoms of an insulin molecule. An insulin molecule consists of 782 atoms and 3,500 electrons. Illustration: Simen Reine-UiO

 

PlasCarb: producing graphene and renewable hydrogen from food waster

I have two tidbits about PlasCarb the first being an announcement of its existence and the second an announcement of its recently published research. A Jan. 13, 2015 news item on Nanowerk describes the PlasCarb project (Note: A link has been removed),

The Centre for Process Innovation (CPI) is leading a European collaborative project that aims to transform food waste into a sustainable source of significant economic added value, namely graphene and renewable hydrogen.

The project titled PlasCarb will transform biogas generated by the anaerobic digestion of food waste using an innovative low energy microwave plasma process to split biogas (methane and carbon dioxide) into high value graphitic carbon and renewable hydrogen.

A Jan. 13, 2015 CPI press release, which originated the news item, describes the project and its organization in greater detail,

CPI  as the coordinator of the project is responsible for the technical aspects in the separation of biogas into methane and carbon dioxide, and separating of the graphitic carbon produced from the renewable hydrogen. The infrastructure at CPI allows for the microwave plasma process to be trialled and optimised at pilot production scale, with a future technology roadmap devised for commercial scale manufacturing.

Graphene is one of the most interesting inventions of modern times. Stronger than steel, yet light, the material conducts electricity and heat. It has been used for a wide variety of applications, from strengthening tennis rackets, spray on radiators, to building semiconductors, electric circuits and solar cells.

The sustainable creation of graphene and renewable hydrogen from food waste in provides a sustainable method towards dealing with food waste problem that the European Union faces. It is estimated that 90 million tonnes of food is wasted each year, a figure which could rise to approximately 126 million tonnes by 2020. In the UK alone, food waste equates to a financial loss to business of at least £5 billion per year.

Dr Keith Robson, Director of Formulation and Flexible Manufacturing at CPI said, “PlasCarb will provide an innovative solution to the problems associated with food waste, which is one of the biggest challenges that the European Union faces in the strive towards a low carbon economy.  The project will not only seek to reduce food waste but also use new technological methods to turn it into renewable energy resources which themselves are of economic value, and all within a sustainable manner.”

PlasCarb will utilise quality research and specialist industrial process engineering to optimise the quality and economic value of the Graphene and hydrogen, further enhancing the sustainability of the process life cycle.

Graphitic carbon has been identified as one of Europe’s economically critical raw materials and of strategic performance in the development of future emerging technologies. The global market for graphite, either mined or synthetic is worth over €10 billion per annum. Hydrogen is already used in significant quantities by industry and recognised with great potential as a future transport fuel for a low carbon economy. The ability to produce renewable hydrogen also has added benefits as currently 95% of hydrogen is produced from fossil fuels. Moreover, it is currently projected that increasing demand of raw materials from fossil sources will lead to price volatility, accelerated environmental degradation and rising political tensions over resource access.

Therefore, the latter stages of the project will be dedicated to the market uptake of the PlasCarb process and the output products, through the development of an economically sustainable business strategy, a financial risk assessment of the project results and a flexible financial model that is able to act as a primary screen of economic viability. Based on this, an economic analysis of the process will be determined. Through the development of a decentralised business model for widespread trans-European implementation, the valorisation of food waste will have the potential to be undertaken for the benefit of local economies and employment. More specifically, three interrelated post project exploitation markets have been defined: food waste management, high value graphite and RH2 sales.

PlasCarb is a 3-year collaborative project, co-funded under the European Union’s Seventh Framework Programme (FP7) and will further reinforce Europe’s leading position in environmental technologies and innovation in high value Carbon. The consortium is composed of eight partners led by CPI from five European countries, whose complimentary research and industrial expertise will enable the required results to be successfully delivered. The project partners are; The Centre for Process Innovation (UK), GasPlas AS (NO), CNRS (FR), Fraunhofer IBP (DE), Uvasol Ltd (UK), GAP Waste Management (UK), Geonardo Ltd. (HU), Abalonyx AS (NO).

You can find PlasCarb here.

The second announcement can be found in a PlasCarb Jan. 14, 2015 press release announcing the publication of research on heterostructures of graphene ribbons,

Few materials have received as much attention from the scientific world or have raised so many hopes with a view to their potential deployment in new applications as graphene has. This is largely due to its superlative properties: it is the thinnest material in existence, almost transparent, the strongest, the stiffest and at the same time the most strechable, the best thermal conductor, the one with the highest intrinsic charge carrier mobility, plus many more fascinating features. Specifically, its electronic properties can vary enormously through its confinement inside nanostructured systems, for example. That is why ribbons or rows of graphene with nanometric widths are emerging as tremendously interesting electronic components. On the other hand, due to the great variability of electronic properties upon minimal changes in the structure of these nanoribbons, exact control on an atomic level is an indispensable requirement to make the most of all their potential.

The lithographic techniques used in conventional nanotechnology do not yet have such resolution and precision. In the year 2010, however, a way was found to synthesise nanoribbons with atomic precision by means of the so-called molecular self-assembly. Molecules designed for this purpose are deposited onto a surface in such a way that they react with each other and give rise to perfectly specified graphene nanoribbons by means of a highly reproducible process and without any other external mediation than heating to the required temperature. In 2013 a team of scientists from the University of Berkeley and the Centre for Materials Physics (CFM), a mixed CSIC (Spanish National Research Council) and UPV/EHU (University of the Basque Country) centre, extended this very concept to new molecules that were forming wider graphene nanoribbons and therefore with new electronic properties. This same group has now managed to go a step further by creating, through this self-assembly, heterostructures that blend segments of graphene nanoribbons of two different widths.

The forming of heterostructures with different materials has been a concept widely used in electronic engineering and has enabled huge advances to be made in conventional electronics. “We have now managed for the first time to form heterostructures of graphene nanoribbons modulating their width on a molecular level with atomic precision. What is more, their subsequent characterisation by means of scanning tunnelling microscopy and spectroscopy, complemented with first principles theoretical calculations, has shown that it gives rise to a system with very interesting electronic properties which include, for example, the creation of what are known as quantum wells,” pointed out the scientist Dimas de Oteyza, who has participated in this project. This work, the results of which are being published this very week in the journal Nature Nanotechnology, therefore constitutes a significant success towards the desired deployment of graphene in commercial electronic applications.

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

Molecular bandgap engineering of bottom-up synthesized graphene nanoribbon heterojunctions by Yen-Chia Chen, Ting Cao, Chen Chen, Zahra Pedramrazi, Danny Haberer, Dimas G. de Oteyza, Felix R. Fischer, Steven G. Louie, & Michael F. Crommie. Nature Nanotechnology (2015) doi:10.1038/nnano.2014.307 Published online 12 January 2015

This article is behind a paywall but there is a free preview available via ReadCube access.

Self-healing (high voltage installations) in the subsea and a search for funding

More concept than reality, nonetheless, the possibilities offered by this Scandinavian research are appealing. From a Dec. 16, 2014 news item on ScienceDaily,

Embryonic faults in subsea high voltage installations are difficult to detect and very expensive to repair. Researchers believe that self-repairing materials could be the answer.

The vital insulating material which encloses sensitive high voltage equipment may now be getting some ‘first aid’.

“We have preliminary results indicating that this is a promising concept, but we need to do more research to check out other solutions and try the technique out under different conditions.” So says SINTEF [largest independent research organisation in Scandinavial researcher Cédric Lesaint, who is hoping that the industry will soon wake up to the idea.

A Nov. 26, 2014 SINTEF press release, which originated the news item, describes the concept in more detail,

The technology used involves so-called ‘microcapsules’, which are added to traditional insulation materials and have the ability to ‘sniff out’ material fatigue and then release repairing molecules. The team working on this project is made up of chemists, physicists and electrical engineers. If they succeed, they may have discovered the next generation of insulating materials which can be applied in costly electrical installations.

The press release then describes a phenomenon named ‘electrical trees’,

So-called electrical trees develop in electrical insulation materials that are approaching the end of their useful lives. Electrical stress fields exploit small weaknesses in the insulation material and generate hair-thin channels that spread through the material like the branches of a tree. When the channels finally reach the surface of the insulation material, the damage is done and short-circuiting will occur.

“Short-circuiting is almost always linked to an electrical tree”, explains Lesaint’s colleague, Øystein Hestad.

Faults of this kind are extremely expensive to repair, especially if they occur in a device installed on an offshore wind farm or a subsea oil production installation – perhaps even under inhospitable Arctic conditions.

Under such conditions, say researchers, self-repairing insulation materials represent a cost-effective alternative to traditional repair methods.

The specific solution the researchers propose (from the press release),

SINTEF researchers have based their work on an established idea developed to repair mechanical damage and cracks in composite materials. The composites are mixed with microcapsules filled with a liquid monomer – single molecules which have the property to join with each other (polymerise) to form long-chain molecules. If cracks or other forms of damage encroach on the capsules, the monomer is released and fills the cracks.

“As far as we know, we’re the first to have tested this technique on damage resulting from electrical stress fields”, says Lesaint.

The microcapsules they incorporated into the insulation materials burst when they encounter one of the branches of an electrical tree. The liquid monomer then invades the thin channels forming the ‘tree’ and polymerises. The channels are filled in and the electrical degradation of the insulation material is halted.

In this way the ‘immune defences’ of the insulation material are strengthened, and the lifetime of the installation extended.

As promising as the research is, the scientists are looking for funds (from the press release),

This summer [2014], the SINTEF research team presented the concept at a conference in Philadelphia, USA.

“Many people were surprised, especially when they realised that we had chosen to share the concept with others”, says Lesaint. “Taking the chance that other researchers might steal such a good idea is a risk we have to take”, he says.

The industry has also expressed some interest, but so far not enough to consider funding further research.

“We’re being met with curious interest, but have been told to come back when we have more test results”, says Lesaint. “The problem is that at present we have insufficient funds to conduct the research needed to carry the project forward”, he says.

Next year [2015?] will thus decide as to whether this self-repairing project will take the step from being a promising concept to becoming the next generation of insulation materials.

You can also find the press release/article by Lars Martin Hjortho here in  a Gemini.no newsletter.

Here’s an illustration the researchers have made available,

Subsea installations can get longer life-time with self-repairing materials. Illustration: SINTEF Energy  [downloaded from http://gemini.no/en/2014/11/self-repairing-subsea-material/]

Subsea installations can get longer life-time with self-repairing materials. Illustration: SINTEF Energy [downloaded from http://gemini.no/en/2014/11/self-repairing-subsea-material/]

Norway and degradable electronics

It’s a bit higgledy-piggledy but a Nov. 20, 2014 news item on Nanowerk highlights some work with degradable electronics taking place in Norway,

When the FM frequencies are removed in Norway in 2017, all old-fashioned radios will become obsolete, leaving the biggest collection of redundant electronics ever seen – a mountain of waste weighing something between 25,000 and 30,000 tonnes.

The same thing is happening with today’s mobile telephones, PCs and tablets, all of which are constantly being updated and replaced faster than the blink of an eye. The old devices end up on waste tips, and even though we in the west recover some materials for recycling, this is only a small proportion of the whole.

And nor does the future bode well with waste in mind. Technologists’ vision of the future is the “Internet of Things”. Electronics are currently printed onto plastics. All products are fitted with sensors designed to measure something, and to make it possible to talk to other devices around them. Davor Sutija is General Manager at the electronics firm Thin Film, and he predicts that in the course of a few years each of us will progress from having a single sensor to having between a hundred and a thousand. This in turn will mean that billions of devices with electronic bar codes will be released onto the market.

Researchers are now getting to grips with this problem. Their aim is to develop processes in which electronics are manufactured in such a way that their entire life cycle is controlled, including their ultimate disappearance.

A Nov. 20, 2014 article by Åse Dragland for the Gemini newsletter (also found as a Nov. 20, 2014 news release on SINTEF [Norwegian: Stiftelsen for industriell og teknisk forskning]), describes the inspiration for the work in Norway while pointing out some signficant differences from US researchers in the approach to creating a commercial application,

In New Orleans in the USA, researchers have made electronic circuits which they implant into surgical wounds following operations on rats. Each wound is sewn up and the electricity in the circuits then accelerates the healing process. After a few weeks, the electronics are dissolved by the body fluids, making it unnecessary to re-open the wound to remove them manually.

In Norway, researchers at SINTEF have now succeeded in making components containing magnesium circuits designed to transfer energy. These are soluble in water and disappear after a few hours.

“We make no secret of the fact that we are putting our faith in the research results coming out of the USA”, says Karsten Husby at SINTEF ICT. “The Americans have made amazing contributions both in relation to medical applications, and towards resolving the issue of waste. We want to try to find alternative approaches to the same problem”, he says.

The circuit containing the small components is printed on a silicon wafer. At only a few nanometres thick, the circuits are extremely thin, and this enables them to dissolve more effectively. Some of the circuit components are made of magnesium, others of silicon, and others of silicon with a magnesium additive.

But the journey to the researchers’ goal from their current position leaves them with more than enough work to do. Making the ultra-thin circuits is a challenge enough in itself, but they also have to find a “coating” or “film” which will act as a protective packaging around the circuits.

The Americans use silk as their coating material, but the Norwegians are not in favour of this. The silk used is made as part of a process which involves the substance lithium, which is banned at MiNaLab – the laboratory where the SINTEF researchers work.

“Lithium generates a technical problem for our lab”, says Geir Uri Jensen, “so we’re considering alternatives, including a variety of plastics”, he says. “In order to achieve this, we’ve brought in some materials scientists here at SINTEF who are very skilled in this field”, he says.

The nature of the coating must be tailored to the time at which the electronics are required to degrade. In some cases this is just one week – in others, four. For example, if the circuit package is designed to be used in seawater, and fitted with sensors for taking measurements from oil spills, the film must be made so that it remains in place for the weeks in which the measurements are being taken.

“When the external fluids penetrate to the “guts” inside the packaging, the circuits begin to degrade. The job must be completed before this happens”, says Karsten Husby.

Geir Uri Jensen makes a sketch and explains how the nano researchers use horizontal and vertical etching processes in the lab to deposit all the layers onto the silicon circuits. And then – how they have to etch and lift the circuit loose from the silicon wafer in order later to transfer it across to the film.

“This works well enough using sensors at full scale”, he says, “but when the wafers are as thin as this, things become more tricky”. Jensen shrugs. “Even if the angle is just a little off, the whole assembly will snap”, he says.

There’s no doubt that as the use of consumer electronics increases, so too does the need to remove obsolete electronic products. Just think of all the cheap electronics built into children’s toys which are thrown away every year.

The removal of “outdated electronics” can also be a very labour-intensive process. Every day, surgeons place implants fitted with sensors into our bodies in order to measure everything from blood pressure and pressure on the brain, to how our hip implants are working. Some weeks later they have to operate again in order to remove the electronics.

But not everyone is interested in the new technologies developing in this field. Electronics companies which manufacture circuits are more interested in selling their products than in investing in research that results in their products disappearing. And companies which rely on recycling for their revenues may regard these new ideas as a threat to their existence.
Eco-friendly electronics are on the way

“It’s important to make it clear that we’re not manufacturing a final product, but a demo that can show that an electronic component can be made with properties that make it degradable”, says Husby. “Our project is now in its second year, but we’ll need a partner active in the industry and more funding in the years ahead if we’re to meet our objectives. There’s no doubt that eco-friendly electronics is a field which will come into its own, also here in Norway. And we’ve made it our mission to reach our goals”, he says.

Here’s an image of dissolving electronic circuits made available by the researchers,

Electronic circuits can be implanted into surgical wounds and assist the healing process by accelerating wound closure. After a few weeks, the electronics are dissolved by the body fluids, making it unnecessary to re-open the wound to remove them manually. Photos: Werner Juvik/SINTEF - See more at: http://gemini.no/en/2014/11/tomorrows-degradable-electronics/#sthash.Erh1sZp2.dpuf

Electronic circuits can be implanted into surgical wounds and assist the healing process by accelerating wound closure. After a few weeks, the electronics are dissolved by the body fluids, making it unnecessary to re-open the wound to remove them manually. Photos: Werner Juvik/SINTEF – See more at: http://gemini.no/en/2014/11/tomorrows-degradable-electronics/#sthash.Erh1sZp2.dpuf

The researcher most associated with this kind of work is John Rogers at the University of Illinois at Urbana-Champaign and you can read more about biodegradable/dissolving electronics in a Sept. 27, 2012 article (open access) by Katherine Bourzac for Nature magazine. You can find more information about Thin Film Electronics or Thinfilm Electronics (mentioned in the third paragraph of the news item on Nanowerk) website here.

Canada’s National Science and Technology Week (Oct. 17 – 26, 2014) followed by Transatlantic Science Week (Oct. 27 – 29, 2014)

Canada’s National Science and Technology Week (it’s actually 10 days) starts on today, Oct. 17, 2014 this year. You can find a listing of events across the country on the National Science and Technology Week Events List webpage (Note: I have reformatted the information I’ve excerpted from the page but all the details remain the same and links have been removed),

Alberta

Medicine Hat     Praxis Annual Family Science Olympics     Medicine Hat High School Taylor Science Centre (enter on 5th street)     Saturday, October 18, 2014, 10:00 a.m. – 3:00 p.m.     Praxis will be hosting their annual Family Science Olympics. The day will consist of ten hands on science challenges that each family can participate in. If you complete eight of the ten, you will be entered into the draw for the grand prize of a remote control helicopter with a camera. Each “family” must have at least one person over the age of 18. The event is free and will have something for all ages.

British Columbia

Vancouver     First Responder’s weekend     Science World at TELUS World of Science     Saturday October 18 & Sunday October 19, 10am – 6pm both days     First responders are an important and integral part of every community. Join Vancouver firefighters, BC paramedics, Vancouver police, Ecomm 911 and the Canadian Border Services Agency as they showcase who our first responders are, what they do, the technology they use and the role that science plays in their work. Explore emergency technology inside and emergency response vehicles outside the building.

Manitoba

Dugald     Bees, Please     Springfield Public Library, Dugald, Manitoba     October 17, 22, and 24th for programs. We will have the display set up for the duration, from Oct 17-26th. 10 a.m to 8 p.m.     Preschool programs all week will feature stories and crafts on bees and their importance in the world. Kids in the Kitchen, menu selections will feature the use of honey all week. We will have displays of honey, bees and farming with local Ag. Society assistance.

New Brunswick

Dieppe     Tech Trek 2014     Dieppe Arts and Culture Centre     Saturday, October 25, 2014, 9 AM – 12 PM     Come join us for a morning filled with science and tech activities for children of all ages! Admission to this event is free!

Ontario

Ottawa     Funfest     Booth Street Complex(Corner of Booth and Carling)     Sunday, October 19, 2014 – 11:00 am to 4:00 pm     Science Funfest is an open house event that takes place at Natural Resources Canada’s Booth Street Complex, at the corner of Carling Avenue and Booth Street in Ottawa. It’s a wonderful opportunity for children and anyone interested in science to engage in presentations and gain hands on science experience by participating in activities that will showcase the importance of science in a fun and interactive way. Last year’s event featured approximately 70 interactive exhibits on subjects ranging from ‘Slime’ to ‘Canada’s Forest Insects’.

Toronto     Science Literacy Week     Gerstein Science Information Centre, University of Toronto     September 22-28, 2014   [emphasis mine]  Science literacy week is a city wide effort to provide access to some of the best science communicators of all time.  Through book displays, links to online content, documentary screenings and lecture series, the aim is to showcase how captivating science really is.    The science literacy week’s goal is to give people the opportunity to marvel at the discoveries and developments of the last few centuries of scientific thought.

Québec

Sherbrooke     Conférence “La crystallographie : art, science et chocolat!” Par Alexis Reymbault     Musée de la nature et des sciences de Sherbrooke     October 22, 2014     French only.

Saskatchewan

Saskatoon     See the Light: Open House at the Canadian Light Source     Canadian Light Source, 44 Innovation Blvd.     Saturday, October 18, 2014, 9-11:30 am and 1-4 pm     Tour the synchrotron and talk with young researchers and see where and how they use the synchrotron to study disease. Advance registration required: http://fluidsurveys.usask.ca/s/CLS/

At this point, there seem to be fewer events than usual but that may be due to a problem the organizer (Canada’s Science and Technology Museums Corporation) has been dealing with since Sept. 11, 2014. That day, they had to close the country’s national Science and Technology Museum due to issues with airbourne mould (Sept. 11, 2014 news item on the Globe and Mail website). As for what Toronto’s Science Literacy Week 2014, which took place during September, is doing on a listing of October events is a mystery to me unless this is an attempt to raise awareness for the 2015 event mentioned on the Science Literacy Week 2014  webpage.

Transatlantic Science Week (Oct. 26 – 29, 2014), which is three days not a week, is being held in Toronto, Ontario and it extends (coincidentally or purposefully) Canada’s National Science and Technology Week (Oct. 17 – 26, 2014). Here’s more about Transatlantic Science Week from a UArctic (University of the Arctic) Sept. 12, 2014 blog posting (Note 1: UArctic announced the dates as Oct. 27 – 29, 2014 as opposed to the dates from the online registration website for the event; Note 2: Despite the error with the dates the information about the week is substantively the same as the info. on the registration webpage)

The Transatlantic Science Week is an annual trilateral science and innovation conference that promotes the collaboration between research, innovation, government, and business in Canada, the United States and Norway.  Held in Toronto, Canada, this year’s theme focuses on “The Arctic: Societies, Sustainability, and Safety”.

The Transatlantic Science Week 2014 will examine challenges and opportunities in the Arctic through three specialized tracks: (1) Arctic climate science, (2) Arctic safety and cross border knowledge, and (3) Arctic research-based industrial development and resource management. Business opportunities in the Arctic is an essential part of the program.

The evernt [sic] provides a unique arena to facilitate critical dialogue and initiate new collaboration between key players with specific Arctic knowledge.

You can find more information about the programme and other meeting details here but you can no longer register online, all new registrations will be done onsite during the meeting.

Germany’s nano-supercapacitors for electric cars

Kudos to the writer for giving a dull topic, supercapacitors and electric cars, a jolt of life. From a July 24, 2014 news item on ScienceDaily,

Innovative nano-material based supercapacitors are set to bring mass market appeal a good step closer to the lukewarm public interest in Germany. [emphasis mine] This movement is currently being motivated by the advancements in the state-of-the-art of this device.

A July 1, 2014 Fraunhofer-Gesellschaft press release (also on EurekAlert), which originated the news item and, sadly, did not reveal the writer’s name, goes on in this refreshing fashion,

Electric cars are very much welcomed in Norway and they are a common sight on the roads of the Scandinavian country – so much so that electric cars topped the list of new vehicle registrations for the second time. This poses a stark contrast to the situation in Germany, where electric vehicles claim only a small portion of the market. Of the 43 million cars on the roads in Germany, only a mere 8000 are electric powered. The main factors discouraging motorists in Germany from switching to electric vehicles are the high investments cost, their short driving ranges and the lack of charging stations. Another major obstacle en route to the mass acceptance of electric cars is the charging time involved. The minutes involved in refueling conventional cars are so many folds shorter that it makes the situation almost incomparable. However, the charging durations could be dramatically shortened with the inclusion of supercapacitors. These alternative energy storage devices are fast charging and can therefore better support the use of economical energy in electric cars. Taking traditional gasoline-powered vehicles for instance, the action of braking converts the kinetic energy into heat which is dissipated and unused. Per contra, generators on electric vehicles are able to tap into the kinetic energy by converting it into electricity for further usage. This electricity often comes in jolts and requires storage devices that can withstand high amount of energy input within a short period of time. In this example, supercapacitors with their capability in capturing and storing this converted energy in an instant fits in the picture wholly. Unlike batteries that offer limited charging/discharging rates, supercapacitors require only seconds to charge and can feed the electric power back into the air-conditioning systems, defogger, radio, etc. as required.

So, the Norwegians have embraced electric cars while the Germans have remained reluctant. The writer offers a clear explanation of supercapacitors and mentions a solution for improving the electric vehicle acceptance rate in Germany (from the press release)

Rapid energy storage devices are distinguished by their energy and power density characteristics – in other words, the amount of electrical energy the device can deliver with respect to its mass and within a given period of time. Supercapacitors are known to possess high power density, whereby large amounts of electrical energy can be provided or captured within short durations, albeit at a short-coming of low energy density. The amount of energy in which supercapacitors are able to store is generally about 10% that of electrochemical batteries (when the two devices of same weight are being compared). This is precisely where the challenge lies and what the “ElectroGraph” project is attempting to address.

ElectroGraph is a project supported by the EU and its consortium consists of ten partners from both research institutes and industries. One of the main tasks of this project is to develop new types of supercapacitors with significantly improved energy storage capacities. As the project is approaches its closing phase in June, the project coordinator at Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart, Carsten Glanz explained the concept and approach taken en route to its successful conclusion: “during the storage process, the electrical energy is stored as charged particles attached on the electrode material.” “So to store more energy efficiently, we designed light weight electrodes with larger, usable surfaces.”

Next, the ‘nano’ aspect (graphene) of this particular project is explained,

In numerous tests, the researcher and his team investigated the nano-material graphene, whose extremely high specific surface area of up to 2,600 m2/g and high electrical conductivity practically cries out for use as an electrode material. It consists of an ultrathin monolayer lattice made of carbon atoms. When used as an electrode material, it greatly increases the surface area with the same amount of material. From this aspect, graphene is showing its potential in replacing activated carbon – the material that has been used in commercial supercapacitors to date – which has a specific surface area between 1000 and 1800 m2/g.

“The space between the electrodes is filled with a liquid electrolyte,” revealed Glanz. “We use ionic liquids for this purpose. Graphene-based electrodes together with ionic liquid electrolytes present an ideal material combination where we can operate at higher voltages.” “By arranging the graphene layers in a manner that there is a gap between the individual layers, the researchers were able to establish a manufacturing method that efficiently uses the intrinsic surface area available of this nano-material. This prevents the individual graphene layers from restacking into graphite, which would reduce the storage surface and consequently the amount of energy storage capacity. “Our electrodes have already surpassed commercially available one by 75 percent in terms of storage capacity,” emphasizes the engineer. “I imagine that the cars of the future will have a battery connected to many capacitors spread throughout the vehicle, which will take over energy supply during high-power demand phases during acceleration for example and ramming up of the air-conditioning system. These capacitors will ease the burden on the battery and cover voltage peaks when starting the car. As a result, the size of massive batteries can be reduced.”

Whether this effort has already been or, at some time in the future, will be demonstrated is not entirely clear to me,

In order to present the new technology, the ElectroGraph consortium developed a demonstrator consisting of supercapacitors installed in an automobile side-view mirror and charged by a solar cell in an energetically self-sufficient system. The demonstrator will be unveiled at the end of May [2015?] during the dissemination workshop at Fraunhofer IPA.

I imagine improved supercapacitors will be prove to be an enticement for more than one reluctant electric car purchaser no matter where they reside.

Martini with your salad? an update on Janus particles and emulsification

Close to a year since I first posted about this research (my July 8, 2013 posting about oil, electricity, and emulsification), scientists have published their latest work on using electricity to control nanoparticles. A June 26, 2014 Polish Academy of Sciences press release (also on EurekAlert) provides this summary,

Everything depends on how you look at them. Looking from one side you will see one face; and when looking from the opposite side – you will see a different one. So appear Janus capsules, miniature, hollow structures, in different fragments composed of different micro- and nanoparticles. Theoreticians were able to design models of such capsules, but a real challenge was to produce them. Now, Janus capsules can be produced easily and at low cost.

Before describing the process for producing Janus capsules, an explanation of Janus (a Roman god) and the problem the scientists were trying to solve (from the press release),

Janus, the old Roman god of beginnings and transitions, attracted believers’ attention with his two faces, each looking to different direction of the world. Janus capsules – ‘bubbles’ made up of two shells stuck one another, each composed of micro- or nanoparticles of different properties – have been for some time attracting the researchers’ attention. They see in the capsules an excellent tool for transporting drugs and a vehicle leading to innovative materials. To have, however, Janus capsules generally accessible, efficient methods for their mass production must be developed. An important step in this direction is the achievement of researchers from the Norwegian and French research institutions and the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, reported recently in one of the most reputable scientific journals: “Nature Communications”.

At present, it is not a problem to produce Janus spheres – round, entirely filled micro- and nanoobjects with one part having different properties than the other. Such spheres can be, for instance, produced by sticking together two drops of different substances. After merging, the new drop requires a sufficiently fast fixation only, e.g., by cooling it down or initiating polymerisation of its materials. For instance, Janus spheres are particles with white and black halves, used for image generation in electrophoretic displays incorporated in e-book reading devices.

“Janus capsules differ from Janus spheres: the former are hollow structures, and their partially permeable shell is made of colloidal particles. How to make such a ‘two-faced bubble’ using micro- and nanoparticles? Many researchers reflect on the problem. We proposed a really not complicated solution”, says Dr Zbigniew Rozynek (IPC PAS [Institute of Physical Chemistry Polish Academy of Sciences]), who experimentally studied Janus capsules during his postdoctoral training at Norwegian University of Science and Technology in Trondheim.

Here’s an illustration the researchers have provided,

Caption: These are typical capsules (mainly Janus capsules) obtained with the method described in the press release of the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw. Credit: adopted from Nat. Commun. 5, 3945 (2014)

Caption: These are typical capsules (mainly Janus capsules) obtained with the method described in the press release of the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw.
Credit: adopted from Nat. Commun. 5, 3945 (2014)

Here’s how the researchers solved their problem (from the press release),

In their experiments, an international team of researchers produced Janus capsules with drops of single millilitres in volume. The drops were coated, for instance, with polystyrene or glass nanoparticles with diameters of about 500 nm (billionth parts of a meter) or 1000 nm, respectively. Also differently coloured polyethylene particles were used.

The experiments were performed with oil drops suspended in another oil. To a so prepared environment micro- or nanoparticles of one type were placed and deposited on the surface of a selected drop. Then, particles of another type were brought to the surface of the second drop. Due to the action of capillary forces, the particles were durably kept on the surfaces of both drops, being approximately uniformly distributed.

When an external electric field was turned on, microflows were induced inside and outside the drops. The microflows transported the particles toward the electric ‘equator’. In this step, the packing of colloidal particles could be controlled by shaking the drops in a slowly alternating electric field. The way how the particles are packed is an important factor, as it determines the number and size of pores of the future capsule, and consequently the capsule permeability.

The microflows around the electric equators of the drops resulted in formation of a ring-shaped ribbon, composed of densely packed particles , whereas both electric ‘poles’ became particles-free regions. At the same time, the poles of each drop were acquiring opposite electric charges.

Opposite electric charges attract one another, so the drops with charged poles were heading to each other. In this step, the only thing to do was to convince both drops not only to adjoin with their poles, but actually to merge. For that purpose the long-known electrocoalescence was used: the drops were stimulated for faster merging by an electric field. Finally the drops electrocoalesced, resulting in the formation of a Janus capsule. Due to a dense packing of particles within the capsule the particles of different types virtually did not mix with each other.

It’s like the famous James Bond’s martini: it was always to be shaken, not stirred“, laughs Dr Rozynek. [emphasis mine]

The ultimate capsule appearance was determined by the number of particles deposited on the surfaces of initial drops. If the particles covered both drops with a uniform film, extending almost to the poles, the coalescence resulted in a non-spherical structure. When empty areas around the poles were suitably larger, the Janus capsules acquired a spherical shape. Finally, if the ribbons around the equators of the initial drops were narrow, the coalescence resulted in formation of a structure, which could be called a Janus ring.

The rings with two parts composed of two different types of particles provide interesting opportunities. They can be further stuck each other and produce more complex striped structures. The capsules could be then composed of alternately placed strips of particles, with each strip having different properties than its neighbours.

Janus capsules enable encapsulation of microobjects, nanoparticles or molecules, which must be protected against the environment because of their sensitivity or reactivity. Different properties of both capsule parts make it easier to control the movement of the capsules and the release of their contents. In view of these factors, Janus capsules may find numerous applications. The proposed method for producing the Janus capsules is potentially of great importance for pharmaceutical, dye or food industries, as well as for the development of materials engineering and medicine.

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

Electroformation of Janus and patchy capsules by Zbigniew Rozynek, Alexander Mikkelsen, Paul Dommersnes, & Jon Otto Fossum. Nature Communications 5, Article number: 3945 doi:10.1038/ncomms4945 Published 23 May 2014

This is an open access paper,

Preparing nanocellulose for eventual use in* dressings for wounds

Michael Berger writes about a medical application for wood-based nanocellulose in an April 10, 2014 Nanowerk Spotlight article by featuring some recent research from Norway (Note: Links have been removed),

Cellulose is a biopolymer consisting of long chains of glucose with unique structural properties whose supply is practically inexhaustible. It is found in the cell walls of plants where it serves to provide a supporting framework – a sort of skeleton. Nanocellulose from wood – i.e. wood fibers broken down to the nanoscale – is a promising nanomaterial with potential applications as a substrate for printing electronics, filtration, or biomedicine.

Researchers have now reported on a method to control the surface chemistry of nanocellulose. The paper appeared in the April 8, 2014 online edition of the Journal of Biomaterials Applications (“Pretreatment-dependent surface chemistry of wood nanocellulose for pH-sensitive hydrogels”).

Using a specific chemical pretreatment as example (carboxymethylation and periodate oxidation), a team from the Paper and Fibre Research Institute (PFI) in Norway demonstrated that they could manufacture nanofibrils with a considerable amount of carboxyl groups and aldehyde groups, which could be applied for functionalizing the material.

The Norwegian researchers are working within the auspices of PFI‘s NanoHeal project featured in my Aug. 23, 2012 posting. It’s good to see that progress is being made. From the Berger’s article,

A specific activity that the PFI researchers and collaborators are working with in the NanoHeal project is the production of an ultrapure nanocellulose which is important for biomedical applications. Considering that the nanocellulose hydrogel material can be cross-linked and have a reactive surface chemistry there are various potential applications.

“A concrete application that we are working with in this specific case is as dressing for wound healing, another is scaffolds,” adds senior research scientist and co-author Kristin Syverud.

“Production of an ultrapure nanocellulose quality is an activity that we are intensifying together with our research partners at the Institute of Cancer Research and Molecular Medicine in Trondheim,” notes Chinga-Carrasco [Gary Chinga-Carrasco, a senior research scientist at PFI]. “The results look good and we expect to have a concrete protocol for production of ultrapure nanocellulose soon, for an adequate assessment of its biocompatibility.”

“We have various groups working with assessment of the suitability of nanocellulose as a barrier against wound bacteria and also with the assessment of the cytotoxicity and biocompatibility,” he says. “However, as a first step we have intensified our work on the production of nanocellulose that we expect will be adequate for wound dressings, part of these activities are described in this paper.”

I suggest reading Berger’s article in its totality for a more detailed description of the many hurdles researchers still have to overcome. For the curious, here’s a link to and a citation for the paper,

Pretreatment-dependent surface chemistry of wood nanocellulose for pH-sensitive hydrogels by Gary Chinga-Carrasco & Kristin Syverud. Published online before print April 8, 2014, doi: 10.1177/0885328214531511 J Biomater Appl April 8, 2014 0885328214531511

This paper is behind a paywall.

I was hoping to find someone from this group in the list of speakers for 2014 TAPPI Nanotechnology conference website here (officially known as 2014 TAPPI [Technical Association of the Pulp and Paper Industry] International Conference on Nanotechnology for Renewable Materials) being held in Vancouver, Canada (June 23-26, 2014) but had no luck.

* ‘as’ changed to ‘in’ Apr.14.14 10:50 am PDT in headline

Norwegians hoping to recover leftover oil with nanotechnology-enabled solutions

Sabina Griffith’s Jan. 21, 2013 article for Dailyfusion.net profiles two petroleum-themed research projects funded by the Research Council of Norway,

Two new research projects are receiving funding from the Research Council of Norway to develop nanoparticles that can dislodge leftover oil that remains trapped in reservoirs after conventional recovery has been completed.

Every percentage point of enhanced oil recovery rate represents billions in revenues.

“Nanotechnology is a generic technology with the potential for a wide variety of industrial applications,” says Aase Marie Hundere, Special Adviser at the Research Council and part of the NANO2021 program secretariat. “The petroleum industry is Norway’s largest, with vast international potential. Collaboration with the PETROMAKS 2 program provides an excellent opportunity to attract projects that involve specific users from industry.”

A Jan. 17, 2014 Research Council of Norway news release by Claude R. Olsen/Else Lie. Translation: Darren McKellep/Carol B. Eckmann describes first one project and its proponents,

Plugging errant water paths with gel

One of the problems with reservoirs that have been producing petroleum for an extended period is that the water injected flushes less and less oil out. Eventually the injected water is wasted, flowing through the same water-saturated zones rather than being diverted through new areas still containing mobile oil.

SINTEF [Scandinavia’s largest independent research organization] Petroleum Research is heading a project to develop chemical systems that can seal off these zones by sending a solution of nanoparticles and polymers down into the reservoir to the areas where the operator wants to prevent water from flowing. Once they are in position the particles, together with the polymers, will form a gelatinous structure (a gel) that prevents water from flowing through.
It may take the particles weeks or months to make their way through the reservoir, so the project researchers will have to figure out how to keep the gel from forming before the particles have reached their intended destination.

Another critical point will be to discover how the particles are transported through the porous rock: Will they slip through easily to their destination or get caught up in the pore walls along the way?

Together with NTNU, the University of Kansas and a number of petroleum companies, SINTEF will investigate two alternative solutions. Both are based on silica nanoparticles whose surface has been engineered to bind polymers together and form a gel. Developed by SINTEF Materials and Chemistry, the nanoparticles are similar to those used in certain products by Norwegian paint producer Jotun and in other products.

In the first alternative, chemicals will be used to deactivate the surface of the nanoparticles – keeping them passive for weeks or even months – before being activated to bind the polymers together at their destination point.

In the second alternative, active nanoparticles will be packaged into larger nanoparticles that transport them to the point where they are to be released in order to form the gel. The smaller particles will be produced by SINTEF. The University of Kansas has developed the transport particles and is already testing them in field experiments at North American oil reservoirs.

Project manager Torleif Holt of SINTEF Petroleum Research sees great potential for the technology, if successful.

“In the course of our three-and-a-half-year project period, we hope to have learned enough to know whether this method is viable,” he explains. “We would then able to estimate the quantities of nanoparticles needed and have some idea about when this is a financially feasible option.”

Here’s an image of trapped oil, gas, and water,

Functionalised particles to speed up oil flow While the SINTEF project focuses on plugging holes, the NTNU-led project is looking to speed up the flow of oil. Much of a reservoir’s oil remains trapped in small rock pores. NTNU researchers will be customising nanoparticles that can help to dislodge this oil and dramatically increase the amount of oil that can be recovered.  One method will utilise “Janus particles”, which feature a special surface of two different hemispheres: one is hydrophilic (attracted to water), the other hydrophobic (attracted to oil). Down in the reservoir, where both oil and water are found, the nanoparticles will spin like wheels and push the oil forward. “This is an early-stage project,” says project manager Jianying He, an associate professor at the NTNU Nanomechanical Lab. “But the idea is very exciting and has major potential for raising the recovery rate of Norwegian oil.” The petroleum companies Det norske and Wintershall are signed on as partners, and project researchers will be communicating with Statoil as well. The University of Houston is the research partner. The second method involves changing the surface charge of nanoparticles to make them capable of slipping between a reservoir’s oil and rock. If development proceeds as planned, Professor He estimates that the nanoparticles will be on the market in roughly seven years. She sees two challenges to using nanoparticles for enhanced recovery: HSE and production capacity. HSE should not be problematic in this case, as studies show that silica-based particles are not hazardous to the environment. Production capacity, however, may prove to be an obstacle to large-scale utilisation of nanoparticles. Petroleum companies would need millions of tonnes of nanoparticles daily. Currently there is no facility that can produce such quantities.  [downloaded from http://www.forskningsradet.no/en/Newsarticle/Nanotechnology_to_recover_stubborn_oil/1253992231414/p117731575391]

Microscope image of reservoir rock. The rock pores (shown in blue) may contain trapped oil, gas and water. Nanoparticles can be used to recover more of the residual oil. (Photo: Ingrid Anne Munz) [downloaded from http://www.forskningsradet.no/en/Newsarticle/Nanotechnology_to_recover_stubborn_oil/1253992231414/p117731575391]

The news release then describes the other project and its proponents,

Functionalised particles to speed up oil flow

While the SINTEF project focuses on plugging holes, the NTNU [Norges teknisk-naturvitenskapelige universitet; Norwegian University of Science and Technology]-led project is looking to speed up the flow of oil. Much of a reservoir’s oil remains trapped in small rock pores. NTNU researchers will be customising nanoparticles that can help to dislodge this oil and dramatically increase the amount of oil that can be recovered.

One method will utilise “Janus particles”, which feature a special surface of two different hemispheres: one is hydrophilic (attracted to water), the other hydrophobic (attracted to oil). Down in the reservoir, where both oil and water are found, the nanoparticles will spin like wheels and push the oil forward.

“This is an early-stage project,” says project manager Jianying He, an associate professor at the NTNU Nanomechanical Lab. “But the idea is very exciting and has major potential for raising the recovery rate of Norwegian oil.”

The petroleum companies Det norske and Wintershall are signed on as partners, and project researchers will be communicating with Statoil as well. The University of Houston is the research partner.

The second method involves changing the surface charge of nanoparticles to make them capable of slipping between a reservoir’s oil and rock.

If development proceeds as planned, Professor He estimates that the nanoparticles will be on the market in roughly seven years. She sees two challenges to using nanoparticles for enhanced recovery: HSE  [health, safety, and environment?] and production capacity. HSE should not be problematic in this case, as studies show that silica-based particles are not hazardous to the environment.

Production capacity, however, may prove to be an obstacle to large-scale utilisation of nanoparticles. Petroleum companies would need millions of tonnes of nanoparticles daily. Currently there is no facility that can produce such quantities.

I had no idea Norway was so dependent on the petroleum industry. As for the nanoparticles referred to throughout the descriptions for both projects, I’d love to know more about them.