NREL – Meet Three Women Making Waves in Marine Energy Research

March 30, 2020

To offer some light in a tough time, the National Renewable Energy Laboratory (NREL) celebrates Women’s History Month and highlights the innovation and leadership of women in marine energy research.

Representing two national laboratories, NREL and Pacific Northwest National Laboratory (PNNL), as well as the Department of Energy (DOE), the three women featured here direct departments to advance marine energy research and technology, conduct research themselves, and manage projects. These researchers demonstrate the impact women have in the water power industry and exemplify the variety of marine energy careers.

Jennifer Daw

As a senior researcher and group manager in NREL’s Integrated Application Center (IAC), Jennifer Daw focuses her work on integrated strategies for energy, water, and land/food systems, with an emphasis on the water systems, including water utilities, wastewater, hydropower, and marine energy.

Daw began working at NREL nearly a decade ago, and her work to leverage the energy-water-food nexus to develop sustainable solutions has become increasingly relevant over the years. When addressing complex, global issues caused by population growth, extreme weather events, obsolete infrastructure, and other factors, Daw believes that a comprehensive, cross-sectoral approach is key to creating balance that supports the environment, communities, and the economy. See how Daw’s background in water systems sustainability supports the IAC’s systems-based approach.

Carrie Schmaus

Carrie Schmaus is an Oak Ridge Institute for Science and Education Science, Technology, and Policy Fellow in DOE’s Water Power Technologies Office (WPTO). She has a background in marine science and policy and joined WPTO as a Sea Grant Knauss Fellow.

For Schmaus, her work at DOE is driven by her passion for marine energy research and the impact it has on communities, the environment, aspiring marine scientists, and “the greater good.” Read why Schmaus encourages diversity in science and technology and her tips on how to get involved in the renewable energy sector.

Genevra Harker-Klimeš

Genevra Harker-Klimeš leads PNNL’s Coastal Sciences Division. An expert in oceanography with a background in the physical aspects of the ocean, Harker-Klimeš develops marine renewable energy devices at PNNL as part of a DOE initiative.

Working in the male-dominated world of oil rigs and boats, she quickly learned that her knowledge and perseverance were useful to advancing in the marine energy field. Harker-Klimeš appreciates that her work at PNNL promotes a cross-section of knowledge, where industry experts collaborate to address the country’s leading energy issues. Learn how Harker-Klimeš’ love for travel, outdoor spaces, and the ocean led her to working in marine energy.

The marine energy industry has the potential to provide consistent, predictable clean power and support global energy demands. Follow in the footsteps of Daw, Schmaus, and Harker-Klimeš and see how other women in water power are paving the way for a more diverse representation in the water power industry through both hydropower and marine energy research.

Heart Attack on a Chip: Scientists Model Conditions of Ischemia on a Microfluidic Device

The microfluidic device containing HL-1 cardiac cells is capable of modeling conditions observed during a heart attack, including a reduction in levels of oxygen. Credit: Tufts University

Researchers led by biomedical engineers at Tufts University invented a microfluidic chip containing cardiac cells that is capable of mimicking hypoxic conditions following a heart attack—specifically when an artery is blocked in the heart and then unblocked after treatment.

The chip contains multiplexed arrays of electronic sensors placed outside and inside the cells that can detect the rise and fall of voltage across individual cell membranes, as well as voltage waves moving across the cell layer, which cause the cells to beat in unison in the chip, just as they do in the heart. After reducing levels of oxygen in the fluid within the device, the sensors detect an initial period of tachycardia (accelerated beat rate), followed by a reduction in beat rate and eventually arrhythmia which mimics cardiac arrest.

The research, published in Nano Letters, is a significant advance toward understanding the electrophysiological responses at the cellular level to ischemic heart attacks, and could be applied to future drug development. The paper was selected by the American Chemical Society as Editors’ Choice, and is available with open access.

Cardiovascular disease (CVD) remains the leading cause of death worldwide, with most patients suffering from cardiac ischemia—which occurs when an artery supplying blood to the heart is partially or fully blocked. If ischemia occurs over an extended period, the heart tissue is starved of oxygen (a condition called “hypoxia”), and can lead to tissue death, or myocardial infarction. The changes in cardiac cells and tissues induced by hypoxia include changes in voltage potentials across the cell membrane, release of neurotransmitters, shifts in gene expression, altered metabolic functions, and activation or deactivation of ion channels.

The biosensor technology used in the microfluidic chip combines multi-electrode arrays that can provide extracellular readouts of voltage patterns, with nanopillar probes that enter the membrane to take readouts of voltage levels (action potentials) within each cell. Tiny channels in the chip allow the researchers to continuously and precisely adjust the fluid flowing over the cells, lowering the levels of oxygen to about 1-4 percent to mimic hypoxia or raising oxygen to 21 percent to model normal conditions. The changing conditions are meant to model what happens to cells in the heart when an artery is blocked, and then re-opened by treatment.

“Heart-on-a-chip models are a powerful tool to model diseases, but current tools to study electrophysiology in those systems are somewhat lacking, as they are either difficult to multiplex or eventually cause damage to the cells,” said Brian Timko, assistant professor of biomedical engineering at Tufts University School of Engineering, and corresponding author of the study. “Signaling pathways between molecules and ultimately electrophysiology occur rapidly during hypoxia, and our device can capture a lot of this information simultaneously in real time for a large ensemble of cells.”

When tested, the extracellular electrode arrays provided a two-dimensional map of voltage waves passing over the layer of cardiac cells, and revealed a predictable wave pattern under normal (21 percent) oxygen levels. In contrast, the researchers observed erratic and slower wave patterns when the oxygen was reduced to 1 percent.

The intracellular nanoprobe sensors provided a remarkably accurate picture of action potentials within each cell. These sensors were arranged as an array of tiny platinum tipped needles upon which the cells rest, like a bed of nails. When stimulated with an electric field, the needles puncture through the cell membrane, where they can begin taking measurements at single cell resolution. Both types of devices were created using photolithography—the technology used to create integrated circuits—which allowed researchers to achieve device arrays with highly reproducible properties.

The extracellular and intracellular sensors together provide information of the eletro-physiological effects of a modeled ischemic attack, including a “time lapse” of cells as they become dysfunctional and then respond to treatment. As such, the microfluidic chip could form the basis of a high throughput platform in drug discovery, identifying therapeutics which help cells and tissues recover normal function more rapidly.

“In the future, we can look beyond the effects of hypoxia and consider other factors contributing to acute heart disease, such as acidosis, nutrient deprivation and waste accumulation, simply by modifying the composition and flow of the medium,” said Timko. “We could also incorporate different types of sensors to detect specific molecules expressed in response to stresses.”

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Study reveals how low oxygen levels in the heart predispose people to cardiac arrhythmias

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More information: Haitao Liu et al, Heart-on-a-Chip Model with Integrated Extra- and Intracellular Bioelectronics for Monitoring Cardiac Electrophysiology under Acute Hypoxia, Nano Letters (2020). DOI: 10.1021/acs.nanolett.0c00076

Journal information: Nano Letters

MIT: An Experimental Peptide could Block Covid-19

MIT chemists are testing a protein fragment that may inhibit coronaviruses’ ability to enter human lung cells.

The research described in this article has been published on a preprint server but has not yet been peer-reviewed by scientific or medical experts.

In hopes of developing a possible treatment for Covid-19, a team of MIT chemists has designed a drug candidate that they believe may block coronaviruses’ ability to enter human cells. The potential drug is a short protein fragment, or peptide, that mimics a protein found on the surface of human cells.

The researchers have shown that their new peptide can bind to the viral protein that coronaviruses use to enter human cells, potentially disarming it.

“We have a lead compound that we really want to explore, because it does, in fact, interact with a viral protein in the way that we predicted it to interact, so it has a chance of inhibiting viral entry into a host cell,” says Brad Pentelute, an MIT associate professor of chemistry, who is leading the research team.

The MIT team reported its initial findings in a preprint posted on bioRxiv, an online preprint server, on March 20. They have sent samples of the peptide to collaborators who plan to carry out tests in human cells.

Molecular targeting

Pentelute’s lab began working on this project in early March, after the Cryo-EM structure of the coronavirus spike protein, along with the human cell receptor that it binds to, was published by a research group in China. Coronaviruses, including SARS-CoV-2, which is causing the current Covid-19 outbreak, have many protein spikes protruding from their viral envelope.

Studies of SARS-CoV-2 have also shown that a specific region of the spike protein, known as the receptor binding domain, binds to a receptor called angiotensin-converting enzyme 2 (ACE2). This receptor is found on the surface of many human cells, including those in the lungs. The ACE2 receptor is also the entry point used by the coronavirus that caused the 2002-03 SARS outbreak.

What Does COVID Mean>

In hopes of developing drugs that could block viral entry, Genwei Zhang, a postdoc in Pentelute’s lab, performed computational simulations of the interactions between the ACE2 receptor and the receptor binding domain of the coronavirus spike protein. These simulations revealed the location where the receptor binding domain attaches to the ACE2 receptor — a stretch of the ACE2 protein that forms a structure called an alpha helix.

“This kind of simulation can give us views of how atoms and biomolecules interact with each other, and which parts are essential for this interaction,” Zhang says. “Molecular dynamics helps us narrow down particular regions that we want to focus on to develop therapeutics.”

The MIT team then used peptide synthesis technology that Pentelute’s lab has previously developed, to rapidly generate a 23-amino acid peptide with the same sequence as the alpha helix of the ACE2 receptor. Their benchtop flow-based peptide synthesis machine can form linkages between amino acids, the buildings blocks of proteins, in about 37 seconds, and it takes less than an hour to generate complete peptide molecules containing up to 50 amino acids.

“We’ve built these platforms for really rapid turnaround, so I think that’s why we’re at this point right now,” Pentelute says. “It’s because we have these tools we’ve built up at MIT over the years.”

They also synthesized a shorter sequence of only 12 amino acids found in the alpha helix, and then tested both of the peptides using equipment at MIT’s Biophysical Instrumentation Facility that can measure how strongly two molecules bind together. They found that the longer peptide showed strong binding to the receptor binding domain of the Covid-19 spike protein, while the shorter one showed negligible binding.

Many variants

Although MIT has been scaling back on-campus research since mid-March, Pentelute’s lab was granted special permission allowing a small group of researchers to continue to work on this project. They are now developing about 100 different variants of the peptide in hopes of increasing its binding strength and making it more stable in the body.

“We have confidence that we know exactly where this molecule is interacting, and we can use that information to further guide refinement, so that we can hopefully get a higher affinity and more potency to block viral entry in cells,” Pentelute says.

In the meantime, the researchers have already sent their original 23-amino acid peptide to a research lab at the Icahn School of Medicine at Mount Sinai for testing in human cells and potentially in animal models of Covid-19 infection.

While dozens of research groups around the world are using a variety of approaches to seek new treatments for Covid-19, Pentelute believes his lab is one of a few currently working on peptide drugs for this purpose. One advantage of such drugs is that they are relatively easy to manufacture in large quantities. They also have a larger surface area than small-molecule drugs.

“Peptides are larger molecules, so they can really grip onto the coronavirus and inhibit entry into cells, whereas if you used a small molecule, it’s difficult to block that entire area that the virus is using,” Pentelute says. “Antibodies also have a large surface area, so those might also prove useful. Those just take longer to manufacture and discover.”

One drawback of peptide drugs is that they typically can’t be taken orally, so they would have to be either administered intravenously or injected under the skin. They would also need to be modified so that they can stay in the bloodstream long enough to be effective, which Pentelute’s lab is also working on.

“It’s hard to project how long it will take to have something we can test in patients, but my aim is to have something within a matter of weeks. If it turns out to be more challenging, it may take months,” he says.

In addition to Pentelute and Zhang, other researchers listed as authors on the preprint are postdoc Sebastian Pomplun, grad student Alexander Loftis, and research scientist Andrei Loas.

New Catalyst Recycles Greenhouse Gases into Fuel and Hydrogen Gas: KAIST and Rice University

       The Korea Advanced Institute of Science and Technology (KAIST

Scientists have taken a major step toward a circular carbon economy by developing a long-lasting, economical catalyst that recycles greenhouse gases into ingredients that can be used in fuel, hydrogen gas, and other chemicals. The results could be revolutionary in the effort to reverse global warming, according to the researchers. The study was published on February 14 in Science.

“We set out to develop an effective catalyst that can convert large amounts of the greenhouse gases carbon dioxide and methane without failure,” said Cafer T. Yavuz, paper author and associate professor of chemical and biomolecular engineering and of chemistry at KAIST.

The catalyst, made from inexpensive and abundant nickel, magnesium, and molybdenum, initiates and speeds up the rate of reaction that converts carbon dioxide and methane into hydrogen gas. It can work efficiently for more than a month.

This conversion is called ‘dry reforming’, where harmful gases, such as carbon dioxide, are processed to produce more useful chemicals that could be refined for use in fuel, plastics, or even pharmaceuticals. It is an effective process, but it previously required rare and expensive metals such as platinum and rhodium to induce a brief and inefficient chemical reaction.

Other researchers had previously proposed nickel as a more economical solution, but carbon byproducts would build up and the surface nanoparticles would bind together on the cheaper metal, fundamentally changing the composition and geometry of the catalyst and rendering it useless.

“The difficulty arises from the lack of control on scores of active sites over the bulky catalysts surfaces because any refinement procedures attempted also change the nature of the catalyst itself,” Yavuz said.

The researchers produced nickel-molybdenum nanoparticles under a reductive environment in the presence of a single crystalline magnesium oxide. As the ingredients were heated under reactive gas, the nanoparticles moved on the pristine crystal surface seeking anchoring points. The resulting activated catalyst sealed its own high-energy active sites and permanently fixed the location of the nanoparticles — meaning that the nickel-based catalyst will not have a carbon build up, nor will the surface particles bind to one another. (Article continues below **)

Read More from Rice University: Rice reactor turns greenhouse gas into pure liquid fuel

This schematic shows the electrolyzer developed at Rice to reduce carbon dioxide, a greenhouse gas, to valuable fuels. At left is a catalyst that selects for carbon dioxide and reduces it to a negatively charged formate, which is pulled through a gas diffusion layer (GDL) and the anion exchange membrane (AEM) into the central electrolyte. At the right, an oxygen evolution reaction (OER) catalyst generates positive protons from water and sends them through the cation exchange membrane (CEM). The ions recombine into formic acid or other products that are carried out of the system by deionized (DI) water and gas. Illustration by Chuan Xia and Demin Liu

 

 

 

(** New catalyst recycles greenhouse gases into fuel and hydrogen gas continues)

“It took us almost a year to understand the underlying mechanism,” said first author Youngdong Song, a graduate student in the Department of Chemical and Biomolecular Engineering at KAIST. “Once we studied all the chemical events in detail, we were shocked.”

The researchers dubbed the catalyst Nanocatalysts on Single Crystal Edges (NOSCE). The magnesium-oxide nanopowder comes from a finely structured form of magnesium oxide, where the molecules bind continuously to the edge. There are no breaks or defects in the surface, allowing for uniform and predictable reactions.

“Our study solves a number of challenges the catalyst community faces,” Yavuz said. “We believe the NOSCE mechanism will improve other inefficient catalytic reactions and provide even further savings of greenhouse gas emissions.”

This work was supported, in part, by the Saudi-Aramco-KAIST CO2 Management Center and the National Research Foundation of Korea.

Other contributors include Ercan Ozdemir, Sreerangappa Ramesh, Aldiar Adishev, and Saravanan Subramanian, all of whom are affiliated with the Graduate School of Energy, Environment, Water and Sustainability at KAIST; Aadesh Harale, Mohammed Albuali, Bandar Abdullah Fadhel, and Aqil Jamal, all of whom are with the Research and Development Center in Saudi Arabia; and Dohyun Moon and Sun Hee Choi, both of whom are with the Pohang Accelerator Laboratory in Korea. Ozdemir is also affiliated with the Institute of Nanotechnology at the Gebze Technical University in Turkey; Fadhel and Jamal are also affiliated with the Saudi-Armco-KAIST CO2 Management Center in Korea.

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Story Source:

Materials provided by The Korea Advanced Institute of Science and Technology (KAIST). Note: Content may be edited for style and length.

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Journal Reference:

1. Youngdong Song, Ercan Ozdemir, Sreerangappa Ramesh, Aldiar Adishev, Saravanan Subramanian, Aadesh Harale, Mohammed Albuali, Bandar Abdullah Fadhel, Aqil Jamal, Dohyun Moon, Sun Hee Choi, Cafer T. Yavuz. Dry reforming of methane by stable Ni–Mo nanocatalysts on single-crystalline MgO. Science, 2020; 367 (6479): 777 DOI: 10.1126/science.aav2412

A Nanoscale Device to Generate High-Power Terahertz Waves – Penetrating paper, clothing, wood and walls, detecting air pollution … THz sources could revolutionize Security and Medical Imaging Systems

The nanoscale terahertz wave generator can be implemented on flexible substrates. Credit: EPFL / POWERlab

Terahertz (THz) waves fall between microwave and infrared radiation in the electromagnetic spectrum, oscillating at frequencies of between 100 billion and 30 trillion cycles per second. These waves are prized for their distinctive properties: they can penetrate paper, clothing, wood and walls, as well as detect air pollution. THz sources could revolutionize security and medical imaging systems. What’s more, their ability to carry vast quantities of data could hold the key to faster wireless communications.

THz waves are a type of non-ionizing radiation, meaning they pose no risk to human health. The technology is already used in some airports to scan passengers and detect dangerous objects and substances.

Despite holding great promise, THz waves are not widely used because they are costly and cumbersome to generate. But new technology developed by researchers at EPFL could change all that. The team at the Power and Wide-band-gap Electronics Research Laboratory (POWERlab), led by Prof. Elison Matioli, built a nanodevice that can generate extremely high-power signals in just a few picoseconds, or one trillionth of a second, which produces high-power THz waves.

The technology, which can be mounted on a chip or a flexible medium, could one day be installed in smartphones and other hand-held devices. The work first-authored by Mohammad Samizadeh Nikoo, a Ph.D. student at the POWERlab, has been published in the journal Nature.

How it works

The compact, inexpensive, fully electric nanodevice generates high-intensity waves from a tiny source in next to no time. It works by producing a powerful “spark,” with the voltage spiking from 10 V (or lower) to 100 V in the range of a picosecond. The device is capable of generating this spark almost continuously, meaning it can emit up to 50 million signals every second. When hooked up to antennas, the system can produce and radiate high-power THz waves.

The device consists of two metal plates situated very close together, down to 20 nanometers apart. When a voltage is applied, electrons surge towards one of the plates, where they form a nanoplasma. Once the voltage reaches a certain threshold, the electrons are emitted almost instantly to the second plate. This rapid movement enabled by such fast switches creates a high-intensity pulse that produces high-frequency waves.

Conventional electronic devices are only capable of switching at speeds of up to one volt per picosecond—too slow to produce high-power THz waves.

The new nanodevice, which can be more than ten times faster, can generate both high-energy and high-frequency pulses. “Normally, it’s impossible to achieve high values for both variables,” says Matioli. “High-frequency semiconductor devices are nanoscale in size. They can only cope with a few volts before breaking out. High-power devices, meanwhile, are too big and slow to generate terahertz waves. Our solution was to revisit the old field of plasma with state-of-the-art nanoscale fabrication techniques to propose a new device to get around those constraints.”

According to Matioli, the new device pushes all the variables to the extreme: “High-frequency, high-power and nanoscale aren’t terms you’d normally hear in the same sentence.”

“These nanodevices, on one side, bring an extremely high level of simplicity and low-cost, and on the other side, show an excellent performance. In addition, they can be integrated with other electronic devices such as transistors. Considering these unique properties, nanoplasma can shape a different future for the area of ultra-fast electronics,” says Samizadeh.

The technology could have wide-ranging applications beyond generating THz waves. “We’re pretty sure there’ll be more innovative applications to come,” adds Matioli.

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Record-breaking terahertz laser beam

A Conversation with a ‘Nano – Entrepreneur’ – Advanced Materials Company Veelo Technologies: National Nanotechnology Initiative

*** Genesis Nanotechnology, Inc. is embarking on a series Interviews and Articles featuring ‘Nano Entrepreneurs’ and University Innovators – their journeys and their stories. To that end we thought to first introduce to our readers the Nanotechnology Entrepreneurship Network (NEN) as resource. You can also Follow Us On Twitter for Updates

 

NNI (National Nanotechnology Initiative) is pleased to launch a new community of interest to support entrepreneurs interested in commercializing nanotechnologies. The Nanotechnology Entrepreneurship Network (NEN) brings new and seasoned entrepreneurs together with the people and resources available to support them.

This emerging network will create a forum for sharing best practices for advancing nanotechnology commercialization and the lessons learned along the technology development pathway. Activities are likely to include a monthly podcast series, webinars, workshops, and town hall discussions.

To kick things off, the inaugural podcast in this series features a conversation between NNCO Director Lisa Friedersdorf and Joe Sprengard, CEO and Founder of Veelo Technologies. Joe talks about his journey as an entrepreneur and shares the advice he received when he was getting started. Check back here for more information, and contact nen@nnco.nano.gov if you would like to join the conversation!

We hope you enjoy watching the Video Below:

More About Veelo Technologies: General Nano manufactures Veelo™, a new-class of lightweight, conductive, multifunctional materials that improve the Size, Weight and Power (SWaP) of next generation air vehicles, including aircraft, rotorcraft, unmanned aerial vehicles (UAV), satellites, and missiles.

Read The Full Story Here

Raising Capital for Early Stage Companies in a Post CoronaVirus Market Meltdown

Recent Market Sell-Offs and Volatility Have Investors on a Roller Coaster of a Ride

After ten years of rising US equities prices, many investors are selling (albeit off the highs) but with large capital gains. This sell-off gives investors a chance to rethink their allocation and potentially focus on private investments in earlier stage companies as a long-term hedge.

Anecdotally having met with hundreds investors over the past 24 months, smaller/private deals were more difficult in an era of seemingly predictable source of 8% plus returns in the public markets.

So what is the case for investing in technology at the earliest stage besides the fact that returns are the best and investors are seeking a long term game now? 

What is Your Investor(s) View of the World?

1. Understand the investor type and hypothesis and craft your pitch in response to their view of the world.A high net worth investor who is an angel, likely has public market exposure, capital gains and a fairly large amount of ongoing hypothesis.

“Take the opportunity to remind your potential angel investors that this is a great time to move investment dollars out of the volatile public markets and into a business that is values-aligned and run by someone they know and trust.”

Angel investing has generated good returns over time for angels. The link below connects to a dense academic paper, however it is recommended that Early Stage Companies should be comfortable with this analysis so you can understand how your potential angels are thinking about this investment

Prediction and Control Under Uncertainty – Outcomes in Angel Investing

Assessing and Comparing Risk

2. Early stage pre-revenue tech startups become in relative terms less risky. At the early stage, risk doesn’t change much in absolute terms but changes dramatically in relative terms. If you at normal times evaluate a pre-seed startup risk to be, say, 100x higher than that of a later-stage company, at the time of crisis this could become only 20x. this of course assumes the crisis is bounded in time.

Finding and Leveraging Unique Advantages

3. Pre-revenue startups have zero exposure to market, and generally benefit from crises, because they can get cheaper workforce (this assumes employees will still want to join a company with financing risk).

If you expect the crisis will take x number of months, and the startup has >x runway, you know it will survive. There are almost no other variables except in the Coronavirus instance, we don’t know x number of months yet.

There’s always capital for companies that have the product market fit and a strong relationship with a diversified set of customers.

Companies should rework their financial models and capital strategy to ensure they can hold-off on deploying capital until they understand business drivers that enable them to become category-owning companies offering a defensible product or service.

If you are able to organize your company to qualify for opportunity zone funding, that could help your potential investor with the capital gains associated with their most recent public company stock sale. 

Source William Rosellini

New Carbon Membrane Generates a Hundred Times More Power – Opens up New Possibilities for Power Generation, Desalination and More Efficient Fuel Cells

A new carbon membrane could someday be used in commercial desalination plants

Leiden chemists have created a new ultrathin membrane only one molecule thick. The membrane can produce a hundred times more power from seawater than the best membranes used today. The researchers have published their findings in Nature Nanotechnology.

Thin and porous

When fresh and saltwater meet, an exchange of salt and other particles takes place. A membrane placed in water is able to harness energy from particles moving from one side to the other. A similar process can also be used to desalinate seawater. Leiden chemists have developed a new membrane that can produce a hundred times more energy than classic membranes and known prototype membranes in scientific literature.

How much power is generated depends on the thickness of the membrane and how porous it is. Researchers were able to create a carbon based membrane that is both porous and thin. That is why it can produce more energy than current membranes, which are either porous or thin, but not both.

Credit: Xue Liu

To create this new membrane, Xue Liu and Grégory Schneider spread a large number of oily molecules on a water surface. These molecular building blocks then form a thin film on their own. By heating the film, the molecules are locked in place, creating a stable and porous membrane. According to Xue Liu, the membrane can be adapted for specific requirements. Liu: “The membrane we’ve created is only two nanometers thick and permeable to potassium ions. We can change the properties of the membrane by using a different molecular building block. That way we can adapt it to suit any need.”

Graphene

The new carbon membrane is similar to graphene, a large flat membrane made up of only carbon atoms. But according to Grégory Schneider, this new membrane is in a whole different category. Schneider: “When making a membrane, a lot of researchers start out with graphene, which is very thin, but not porous. They then try to punch holes in it to make more permeable. We’ve done the reverse by assembling small molecules and building a larger porous membrane from those molecules. Compared to graphene, it contains imperfections, but that’s what gives it its special properties.”

This new membrane combines the best of both worlds. Schneider: “Much of the research in this field was focused on creating better catalysts, membranes were somewhat of a dead end. This new discovery opens up whole new possibilities for power generation, desalination and for building much more efficient fuel cells.”

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Water desalination picks up the pace

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More information: Xue Liu et al. Power generation by reverse electrodialysis in a single-layer nanoporous membrane made from core–rim polycyclic aromatic hydrocarbons, Nature Nanotechnology (2020). DOI: 10.1038/s41565-020-0641-5

Journal information: Nature Nanotechnology

Graphene solar heating film offers new opportunity for efficient thermal energy harvesting

Credit: CC0 Public Domain

Researchers at Swinburne University of Technology’s Centre for Translational Atomaterials have developed a highly efficient solar absorbing film that absorbs sunlight with minimal heat loss and rapidly heats up to 83°C in an open environment.

The graphene metamaterial film has great potential for use in solar thermal energy harvesting and conversion, thermophotovoltaics (directly converting heat to electricity), solar seawater desalination, wastewater treatment, light emitters and photodetectors.

The researchers have developed a prototype to demonstrate the photo-thermal performance and thermal stability of the film. They have also proposed a scalable and low-cost manufacturing strategy to produce this graphene metamaterial film for practical applications.

“In our previous work, we demonstrated a 90 nm graphene metamaterial heat-absorbing film,” says Professor Baohua Jia, founding Director of the Centre for Translational Atomaterials.

“In this new work, we reduced the film thickness to 30 nm and improved the performance by minimising heat loss. This work forms an exciting pillar in our atomaterial research.”

Lead author Dr. Keng-Te Lin says: “Our cost-effective and scalable structured graphene metamaterial selective absorber is promising for energy harvesting and conversion applications. Using our film an impressive solar to vapour efficiency of 96.2 percent can be achieved, which is very competitive for clean water generation using renewable energy source.”

Co-author Dr. Han Lin adds: “In addition to the long lifetime of the proposed graphene metamaterial, the solar-thermal performance is very stable under working conditions, making it attractive for industrial use. The 30 nm thickness significantly reduced the amount of the graphene materials, thus saving the costs, making it accessible for real-life applications.”

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Novel form of graphene-based optical material developed

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More information: Keng-Te Lin et al. Structured graphene metamaterial selective absorbers for high efficiency and omnidirectional solar thermal energy conversion, Nature Communications (2020). DOI: 10.1038/s41467-020-15116-z

Journal information: Nature Communications

Provided by Swinburne University of Technology

Unmasking a hidden killer: Successfully detecting cancer in blood of patients undergoing treatment

Dr Yuling Wang. Credit: CNBP

Pancreatic cancer is one of the most lethal cancers, but difficult to diagnose: few sufferers have symptoms until the cancer has become large or already spread to other organs. Even then, symptoms can be vague and easily misconstrued as more common conditions.

This is why Dr. Yuling Wang is so excited by results of a trial completed in late 2019, which—using plasmonic nanoparticles developed by the Centre for Nanoscale BioPhotonics (CNBP)—successfully detected signs of the cancer in blood of patients undergoing treatment. The paper was recently published in the journal American Chemical Society—Sensors.

“The test gave a very high signal in the blood for late-stage or very serious tumors, where other techniques cannot detect anything,” said Dr. Wang, an associate investigator at the Centre’s Macquarie University node in Sydney, in work led by Prof Nicolle Packer. “We need to test many more patient samples to validate the approach, but the strength of the signal was very encouraging.”

They did this by developing a method, using surface-enhanced Raman spectroscopy nanotags, that simultaneously detects three known pancreatic cancer biomarkers in blood. Known as extracellular vesicles, or EVs, they contain DNA and proteins for cell-to-cell communication and are shed from pancreatic cancer cells into surrounding body fluids. The CNBP method zeros in on three: Glypican-1, epithelial cell adhesion molecules and CD44V6.

Non-invasive screening of cancer biomarkers from blood with handheld Raman reader. Credit: CNBP

For the experiment, biopsies of healthy donors were provided alongside those of known sufferers of pancreatic cancer, in double-blind tests where the researchers did not know which was which. Nevertheless, the blood of sufferers was easily identified. The technique was so sensitive it could spot EVs as small as 113 nanometres in diameter—or less than 1% the width of a human hair—in every millilitre of blood.

The pancreas is part of the digestive system, secreting insulin into the bloodstream to regulate the body’s sugar level as well as important enzymes and hormones into the small intestine to help break down food. Pancreatic cancer is the fifth biggest cancer killer in Australia and has a 5-year survival rate of 8.7%. More than 3000 Australians are diagnosed annually, and surgery to remove the cancer is a long and complex process, requiring long hospital stays.

Because existing blood tests for the protein biomarkers of pancreatic cancer are unreliable, imaging with endoscopic ultrasound or MRI scans is necessary. Even then, anomalies can only be confirmed with a biopsy of the organ, which is invasive and ultimately relies on a trained pathologist to recognize signs of the cancer under a microscope. As a result, there’s some subjectivity involved and cancer can be present but still be missed.

“Our approach is non-invasive—we don’t need to take tissue from the patient, we just use a handheld device to test blood for targeted biomarkers, which gives a very quick result,” Dr. Wang said. It may also help provide earlier diagnosis of the cancer.

While the work is a proof-of-concept, it was also able to detect colorectal and bladder cancer biomarkers—although not as clearly as those for pancreatic cancer. Nevertheless, the results are so encouraging that a commercial partner has committed funding to CNBP so it can develop a handheld spectrometer for cancer biomarkers in blood.

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