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      in Energy

      Preparing students for the new nuclear

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      As nuclear power has gained greater recognition as a zero-emission energy source, the MIT Leaders for Global Operations (LGO) program has taken notice.

      Two years ago, LGO began a collaboration with MIT’s Department of Nuclear Science and Engineering (NSE) as a way to showcase the vital contribution of both business savvy and scientific rigor that LGO’s dual-degree graduates can offer this growing field.

      “We saw that the future of fission and fusion required business acumen and management acumen,” says Professor Anne White, NSE department head. “People who are going to be leaders in our discipline, and leaders in the nuclear enterprise, are going to need all of the technical pieces of the puzzle that our engineering department can provide in terms of education and training. But they’re also going to need a much broader perspective on how the technology connects with society through the lens of business.”

      The resulting response has been positive: “Companies are seeing the value of nuclear technology for their operations,” White says, and this often happens in unexpected ways.

      For example, graduate student Santiago Andrade recently completed a research project at Caterpillar Inc., a preeminent manufacturer of mining and construction equipment. Caterpillar is one of more than 20 major companies that partner with the LGO program, offering six-month internships to each student. On the surface, it seemed like an improbable pairing; what could Andrade, who was pursuing his master’s in nuclear science and engineering, do for a manufacturing company? However, Caterpillar wanted to understand the technical and commercial feasibility of using nuclear energy to power mining sites and data centers when wind and solar weren’t viable.

      “They are leaving no stone unturned in the search of financially smart solutions that can support the transition to a clean energy dependency,” Andrade says. “My project, along with many others’, is part of this effort.”

      “The research done through the LGO program with Santiago is enabling Caterpillar to understand how alternative technologies, like the nuclear microreactor, could participate in these markets in the future,” says Brian George, product manager for large electric power solutions at Caterpillar. “Our ability to connect our customers with the research will provide for a more accurate understanding of the potential opportunity, and helps provide exposure for our customers to emerging technologies.”

      With looming threats of climate change, White says, “We’re going to require more opportunities for nuclear technologies to step in and be part of those solutions. A cohort of LGO graduates will come through this program with technical expertise — a master’s degree in nuclear engineering — and an MBA. There’s going to be a tremendous talent pool out there to help companies and governments.”

      Andrade, who completed an undergraduate degree in chemical engineering and had a strong background in thermodynamics, applied to LGO unsure of which track to choose, but he knew he wanted to confront the world’s energy challenge. When MIT Admissions suggested that he join LGO’s new nuclear track, he was intrigued by how it could further his career.

      “Since the NSE department offers opportunities ranging from energy to health care and from quantum engineering to regulatory policy, the possibilities of career tracks after graduation are countless,” he says.

      He was also inspired by the fact that, as he says, “Nuclear is one of the less-popular solutions in terms of our energy transition journey. One of the things that attracted me is that it’s not one of the most popular, but it’s one of the most useful.”

      In addition to his work at Caterpillar, Andrade connected deeply with professors. He worked closely with professors Jacopo Buongiorno and John Parsons as a research assistant, helping them develop a business model to successfully support the deployment of nuclear microreactors. After graduation, he plans to work in the clean energy sector with an eye to innovations in the nuclear energy technology space.

      His LGO classmate, Lindsey Kennington, a control systems engineer, echoes his sentiments: This is a revolutionary time for nuclear technology.

      “Before MIT, I worked on a lot of nuclear waste or nuclear weapons-related projects. All of them were fission-related. I got disillusioned because of all the bureaucracy and the regulation,” Kennington says. “However, now there are a lot of new nuclear technologies coming straight out of MIT. Commonwealth Fusion Systems, a fusion startup, represents a prime example of MIT’s close relationship to new nuclear tech. Small modular reactors are another emerging technology being developed by MIT. Exposure to these cutting-edge technologies was the main sell factor for me.”

      Kennington conducted an internship with National Grid, where she used her expertise to evaluate how existing nuclear power plants could generate hydrogen. At MIT, she studied nuclear and energy policy, which offered her additional perspective that traditional engineering classes might not have provided. Because nuclear power has long been a hot-button issue, Kennington was able to gain nuanced insight about the pathways and roadblocks to its implementation.

      “I don’t think that other engineering departments emphasize that focus on policy quite as much. [Those classes] have been one of the most enriching parts of being in the nuclear department,” she says.

      Most of all, she says, it’s a pivotal time to be part of a new, blossoming program at the forefront of clean energy, especially as fusion research grows more prevalent.

      “We’re at an inflection point,” she says. “Whether or not we figure out fusion in the next five, 10, or 20 years, people are going to be working on it — and it’s a really exciting time to not only work on the science but to actually help the funding and business side grow.”

      White puts it simply.

      “This is not your parents’ nuclear,” she says. “It’s something totally different. Our discipline is evolving so rapidly that people who have technical expertise in nuclear will have a huge advantage in this next generation.” More

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      in Environment

      Rescuing small plastics from the waste stream

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      As plastic pollution continues to mount, with growing risks to ecosystems and wildlife, manufacturers are beginning to make ambitious commitments to keep new plastics out of the environment. A growing number have signed onto the U.S. Plastics Pact, which pledges to make 100 percent of plastic packaging reusable, recyclable, or compostable, and to see 50 percent of it effectively recycled or composted, by 2025.

      But for companies that make large numbers of small, disposable plastics, these pocket-sized objects are a major barrier to realizing their recycling goals.

      “Think about items like your toothbrush, your travel-size toothpaste tubes, your travel-size shampoo bottles,” says Alexis Hocken, a second-year PhD student in the MIT Department of Chemical Engineering. “They end up actually slipping through the cracks of current recycling infrastructure. So you might put them in your recycling bin at home, they might make it all the way to the sorting facility, but when it comes down to actually sorting them, they never make it into a recycled plastic bale at the very end of the line.”

      Now, a group of five consumer products companies is working with MIT to develop a sorting process that can keep their smallest plastic products inside the recycling chain. The companies — Colgate-Palmolive, Procter & Gamble, the Estée Lauder Companies, L’Oreal, and Haleon — all manufacture a large volume of “small format” plastics, or products less than two inches long in at least two dimensions. In a collaboration with Brad Olsen, the Alexander and I. Michael Kasser (1960) Professor of Chemical Engineering; Desiree Plata, an associate professor of civil and environmental engineering; the MIT Environmental Solutions Initiative; and the nonprofit The Sustainability Consortium, these companies are seeking a prototype sorting technology to bring to recycling facilities for large-scale testing and commercial development.

      Working in Olsen’s lab, Hocken is coming to grips with the complexity of the recycling systems involved. Material recovery facilities, or MRFs, are expected to handle products in any number of shapes, sizes, and materials, and sort them into a pure stream of glass, metal, paper, or plastic. Hocken’s first step in taking on the recycling project was to tour one of these MRFs in Portland, Maine, with Olsen and Plata.

      “We could literally see plastics just falling from the conveyor belts,” she says. “Leaving that tour, I thought, my gosh! There’s so much improvement that can be made. There’s so much impact that we can have on this industry.”

      From designing plastics to managing them

      Hocken always knew she wanted to work in engineering. Growing up in Scottsdale, Arizona, she was able to spend time in the workplace with her father, an electrical engineer who designs biomedical devices. “Seeing him working as an engineer, and how he’s solving these really important problems, definitely sparked my interest,” she says. “When it came time to begin my undergraduate degree, it was a really easy decision to choose engineering after seeing the day-to-day that my dad was doing in his career.”

      At Arizona State University, she settled on chemical engineering as a major and began working with polymers, coming up with combinations of additives for 3D plastics printing that could help fine-tune how the final products behaved. But even working with plastics every day, she rarely thought about the implications of her work for the environment.

      “And then in the spring of my final year at ASU, I took a class about polymers through the lens of sustainability, and that really opened my eyes,” Hocken remembers. The class was taught by Professor Timothy Long, director of the Biodesign Center for Sustainable Macromolecular Materials and Manufacturing and a well-known expert in the field of sustainable plastics. “That first session, where he laid out all of the really scary facts surrounding the plastics crisis, got me very motivated to look more into that field.”

      At MIT the next year, Hocken sought out Olsen as her advisor and made plastics sustainability her focus from the start.

      “Coming to MIT was my first time venturing outside of the state of Arizona for more than a three-month period,” she says. “It’s been really fun. I love living in Cambridge and the Boston area. I love my labmates. Everyone is so supportive, whether it’s to give me advice about some science that I’m trying to figure out, or just give me a pep talk if I’m feeling a little discouraged.”

      A challenge to recycle

      A lot of plastics research today is devoted to creating new materials — including biodegradable ones that are easier for natural ecosystems to absorb, and highly recyclable ones that hold their properties better after being melted down and recast.

      But Hocken also sees a huge need for better ways to handle the plastics we’re already making. “While biodegradable and sustainable polymers represent a very important route, and I think they should certainly be further pursued, we’re still a ways away from that being a reality universally across all plastic packaging,” she says. As long as large volumes of conventional plastic are coming out of factories, we’ll need innovative ways to stop it from piling onto the mountain of plastic pollution. In one of her projects, Hocken is trying to come up with new uses for recycled plastic that take advantage of its lost strength to produce a useful, flexible material similar to rubber.

      The small-format recycling project also falls in this category. The companies supporting the project have challenged the MIT team to work with their products exactly as currently manufactured — especially because their competitors use similar packaging materials that will also need to be covered by any solution the MIT team devises.

      The challenge is a large one. To kick the project off, the participating companies sent the MIT team a wide range of small-format products that need to make it through the sorting process. These include containers for lip balm, deodorant, pills, and shampoo, and disposable tools like toothbrushes and flossing picks. “A constraint, or problem I foresee, is just how variable the shapes are,” says Hocken. “A flossing pick versus a toothbrush are very different shapes.”

      Nor are they all made of the same kind of plastic. Many are made of polyethylene terephthalate (PET, type 1 in the recycling label system) or high-density polyethylene (HDPE, type 2), but nearly all of the seven recycling categories are represented among the sample products. The team’s solution will have to handle them all.

      Another obstacle is that the sorting process at a large MRF is already very complex and requires a heavy investment in equipment. The waste stream typically goes through a “glass breaker screen” that shatters glass and collects the shards; a series of rotating rubber stars to pull out two-dimensional objects, collecting paper and cardboard; a system of magnets and eddy currents to attract or repel different metals; and finally, a series of optical sorters that use infrared spectroscopy to identify the various types of plastics, then blow them down different chutes with jets of air. MRFs won’t be interested in adopting additional sorters unless they’re inexpensive and easy to fit into this elaborate stream.

      “We’re interested in creating something that could be retrofitted into current technology and current infrastructure,” Hocken says.

      Shared solutions

      “Recycling is a really good example of where pre-competitive collaboration is needed,” says Jennifer Park, collective action manager at The Sustainability Consortium (TSC), who has been working with corporate stakeholders on small format recyclability and helped convene the sponsors of this project and organize their contributions. “Companies manufacturing these products recognize that they cannot shift entire systems on their own. Consistency around what is and is not recyclable is the only way to avoid confusion and drive impact at scale.

      “Additionally, it is interesting that consumer packaged goods companies are sponsoring this research at MIT which is focused on MRF-level innovations. They’re investing in innovations that they hope will be adopted by the recycling industry to make progress on their own sustainability goals.”

      Hocken believes that, despite the challenges, it’s well worth pursuing a technology that can keep small-format plastics from slipping through MRFs’ fingers.

      “These are products that would be more recyclable if they were easier to sort,” she says. “The only thing that’s different is the size. So you can recycle both your large shampoo bottle and the small travel-size one at home, but the small one isn’t guaranteed to make it into a plastic bale at the end. If we can come up with a solution that specifically targets those while they’re still on the sorting line, they’re more likely to end up in those plastic bales at the end of the line, which can be sold to plastic reclaimers who can then use that material in new products.”

      “TSC is really excited about this project and our collaboration with MIT,” adds Park. “Our project stakeholders are very dedicated to finding a solution.”

      To learn more about this project, contact Christopher Noble, director of corporate engagement at the MIT Environmental Solutions Initiative. More

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      in Energy

      New MIT internships expand research opportunities in Africa

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      With new support from the Office of the Associate Provost for International Activities, MIT International Science and Technology Initiatives (MISTI) and the MIT-Africa program are expanding internship opportunities for MIT students at universities and leading academic research centers in Africa. This past summer, MISTI supported 10 MIT student interns at African universities, significantly more than in any previous year.

      “These internships are an opportunity to better merge the research ecosystem of MIT with academia-based research systems in Africa,” says Evan Lieberman, the Total Professor of Political Science and Contemporary Africa and faculty director for MISTI.

      For decades, MISTI has helped MIT students to learn and explore through international experiential learning opportunities and internships in industries like health care, education, agriculture, and energy. MISTI’s MIT-Africa Seed Fund supports collaborative research between MIT faculty and Africa-based researchers, and the new student research internship opportunities are part of a broader vision for deeper engagement between MIT and research institutions across the African continent.

      While Africa is home to 12.5 percent of the world’s population, it generates less than 1 percent of scientific research output in the form of academic journal publications, according to the African Academy of Sciences. Research internships are one way that MIT can build mutually beneficial partnerships across Africa’s research ecosystem, to advance knowledge and spawn innovation in fields important to MIT and its African counterparts, including health care, biotechnology, urban planning, sustainable energy, and education.

      Ari Jacobovits, managing director of MIT-Africa, notes that the new internships provide additional funding to the lab hosting the MIT intern, enabling them to hire a counterpart student research intern from the local university. This support can make the internships more financially feasible for host institutions and helps to grow the research pipeline.

      With the support of MIT, State University of Zanzibar (SUZA) lecturers Raya Ahmada and Abubakar Bakar were able to hire local students to work alongside MIT graduate students Mel Isidor and Rajan Hoyle. Together the students collaborated over a summer on a mapping project designed to plan and protect Zanzibar’s coastal economy.

      “It’s been really exciting to work with research peers in a setting where we can all learn alongside one another and develop this project together,” says Hoyle.

      Using low-cost drone technology, the students and their local counterparts worked to create detailed maps of Zanzibar to support community planning around resilience projects designed to combat coastal flooding and deforestation and assess climate-related impacts to seaweed farming activities. 

      “I really appreciated learning about how engagement happens in this particular context and how community members understand local environmental challenges and conditions based on research and lived experience,” says Isidor. “This is beneficial for us whether we’re working in an international context or in the United States.”

      For biology major Shaida Nishat, her internship at the University of Cape Town allowed her to work in a vital sphere of public health and provided her with the chance to work with a diverse, international team headed by Associate Professor Salome Maswine, head of the global surgery division and a widely-renowned expert in global surgery, a multidisciplinary field in the sphere of global health focused on improved and equitable surgical outcomes.

      “It broadened my perspective as to how an effort like global surgery ties so many nations together through a common goal that would benefit them all,” says Nishat, who plans to pursue a career in public health.

      For computer science sophomore Antonio L. Ortiz Bigio, the MISTI research internship in Africa was an incomparable experience, culturally and professionally. Bigio interned at the Robotics Autonomous Intelligence and Learning Laboratory at the University of Witwatersrand in Johannesburg, led by Professor Benjamin Rosman, where he developed software to enable a robot to play chess. The experience has inspired Bigio to continue to pursue robotics and machine learning.

      Participating faculty at the host institutions welcomed their MIT interns, and were impressed by their capabilities. Both Rosman and Maswime described their MIT interns as hard-working and valued team members, who had helped to advance their own work.  

      Building strong global partnerships, whether through faculty research, student internships, or other initiatives, takes time and cultivation, explains Jacobovits. Each successful collaboration helps to seed future exchanges and builds interest at MIT and peer institutions in creative partnerships. As MIT continues to deepen its connections to institutions and researchers across Africa, says Jacobovits, “students like Shaida, Rajan, Mel, and Antonio are really effective ambassadors in building those networks.” More

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      in Environment

      MIT PhD students shed light on important water and food research

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      One glance at the news lately will reveal countless headlines on the dire state of global water and food security. Pollution, supply chain disruptions, and the war in Ukraine are all threatening water and food systems, compounding climate change impacts from heat waves, drought, floods, and wildfires.

      Every year, MIT’s Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) offers fellowships to outstanding MIT graduate students who are working on innovative ways to secure water and food supplies in light of these urgent worldwide threats. J-WAFS announced this year’s fellowship recipients last April. Aditya Ghodgaonkar and Devashish Gokhale were awarded Rasikbhai L. Meswani Fellowships for Water Solutions, which are made possible by a generous gift from Elina and Nikhil Meswani and family. James Zhang, Katharina Fransen, and Linzixuan (Rhoda) Zhang were awarded J-WAFS Fellowships for Water and Food Solutions. The J-WAFS Fellowship for Water and Food Solutions is funded in part by J-WAFS Research Affiliate companies: Xylem, Inc., a water technology company, and GoAigua, a company leading the digital transformation of the water industry.

      The five fellows were each awarded a stipend and full tuition for one semester. They also benefit from mentorship, networking connections, and opportunities to showcase their research.

      “This year’s cohort of J-WAFS fellows show an indefatigable drive to explore, create, and push back boundaries,” says John H. Lienhard, director of J-WAFS. “Their passion and determination to create positive change for humanity are evident in these unique video portraits, which describe their solutions-oriented research in water and food,” Lienhard adds.

      J-WAFS funder Community Jameel recently commissioned video portraitures of each student that highlight their work and their inspiration to solve challenges in water and food. More about each J-WAFS fellow and their research follows.

      Play video

      Katharina Fransen

      In Professor Bradley Olsen’s lab in the Department of Chemical Engineering, Katharina Fransen works to develop biologically-based, biodegradable plastics which can be used for food packing that won’t pollute the environment. Fransen, a third-year PhD student, is motivated by the challenge of protecting the most vulnerable global communities from waste generated by the materials that are essential to connecting them to the global food supply. “We can’t ensure that all of our plastic waste gets recycled or reused, and so we want to make sure that if it does escape into the environment it can degrade, and that’s kind of where a lot of my research really comes in,” says Fransen. Most of her work involves creating polymers, or “really long chains of chemicals,” kind of like the paper rings a lot of us looped into chains as kids, Fransen explains. The polymers are optimized for food packaging applications to keep food fresher for longer, preventing food waste. Fransen says she finds the work “really interesting from the scientific perspective as well as from the idea that [she’s] going to make the world a little better with these new materials.” She adds, “I think it is both really fulfilling and really exciting and engaging.”

      Play video

      Aditya Ghodgaonkar

      “When I went to Kenya this past spring break, I had an opportunity to meet a lot of farmers and talk to them about what kind of maintenance issues they face,” says Aditya Ghodgaonkar, PhD candidate in the Department of Mechanical Engineering. Ghodgaonkar works with Associate Professor Amos Winter in the Global Engineering and Research (GEAR) Lab, where he designs hydraulic components for drip irrigation systems to make them water-efficient, off-grid, inexpensive, and low-maintenance. On his trip to Kenya, Ghodgaonkar gained firsthand knowledge from farmers about a common problem they encounter: clogging of drip irrigation emitters. He learned that clogging can be an expensive technical challenge to diagnose, mitigate, and resolve. He decided to focus his attention on designing emitters that are resistant to clogging, testing with sand and passive hydrodynamic filtration back in the lab at MIT. “I got into this from an academic standpoint,” says Ghodgaonkar. “It is only once I started working on the emitters, spoke with industrial partners that make these emitters, spoke with farmers, that I really truly appreciated the impact of what we’re doing.”

      Play video

      Devashish Gokhale

      Devashish Gokhale is a PhD student advised by Professor Patrick Doyle in the Department of Chemical Engineering. Gokhale’s commitment to global water security stems from his childhood in Pune, India, where both flooding and drought can occur depending on the time of year. “I’ve had these experiences where there’s been too much water and also too little water” he recalls. At MIT, Gokhale is developing cost-effective, sustainable, and reusable materials for water treatment with a focus on the elimination of emerging contaminants and low-concentration pollutants like heavy metals. Specifically, he works on making and optimizing polymeric hydrogel microparticles that can absorb micropollutants. “I know how important it is to do something which is not just scientifically interesting, but something which is impactful in a real way,” says Gokhale. Before starting a research project he asks himself, “are people going to be able to afford this? Is it really going to reach the people who need it the most?” Adding these constraints in the beginning of the research process sometimes makes the problem more difficult to solve, but Gokhale notes that in the end, the solution is much more promising.

      Play video

      James Zhang

      “We don’t really think much about it, it’s transparent, odorless, we just turn on our sink in many parts of the world and it just flows through,” says James Zhang when talking about water. Yet he notes that “many other parts of the world face water scarcity and this will only get worse due to global climate change.” A PhD student in the Department of Mechanical Engineering, Zhang works in the Nano Engineering Laboratory with Professor Gang Chen. Zhang is working on a technology that uses light-induced evaporation to clean water. He is currently investigating the fundamental properties of how light at different wavelengths interacts with liquids at the surface, particularly with brackish water surfaces. With strong theoretical and experimental components, his research could lead to innovations in desalinating water at high energy efficiencies. Zhang hopes that the technology can one day “produce lots of clean water for communities around the world that currently don’t have access to fresh water,” and create a new appreciation for this common liquid that many of us might not think about on a day-to-day basis.

      Play video

      Linzixuan (Rhoda) Zhang

      “Around the world there are about 2 billion people currently suffering from micronutrient deficiency because they do not have access to very healthy, very fresh food,” says chemical engineering PhD candidate Linzixuan (Rhoda) Zhang. This fact led Zhang to develop a micronutrient delivery platform that fortifies foods with essential vitamins and nutrients. With her advisors, Professor Robert Langer and Research Scientist Ana Jaklenec, Zhang brings biomedical engineering approaches to global health issues. Zhang says that “one of the most serious problems is vitamin A deficiency, because vitamin A is not very stable.” She goes on to explain that although vitamin A is present in different vegetables, when the vegetables are cooked, vitamin A can easily degrade. Zhang helped develop a group of biodegradable polymers that can stabilize micronutrients under cooking and storage conditions. With this technology, vitamin A, for example, could be encapsulated and effectively stabilized under boiling water. The platform has also shown efficient release in a simulation of the stomach environment. Zhang says it is the “little, tiny steps every day that are pushing us forward to the final impactful product.” More

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      in Energy

      Finding community in high-energy-density physics

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      Skylar Dannhoff knew one thing: She did not want to be working alone.

      As an undergraduate at Case Western Reserve University, she had committed to a senior project that often felt like solitary lab work, a feeling heightened by the pandemic. Though it was an enriching experience, she was determined to find a graduate school environment that would foster community, one “with lots of people, lots of collaboration; where it’s impossible to work until 3 a.m. without anyone noticing.” A unique group at the Plasma Science and Fusion Center (PSFC) looked promising: the High-Energy-Density Physics (HEDP) division, a lead partner in the National Nuclear Security Administration’s Center for Excellence at MIT.

      “It was a shot in the dark, just more of a whim than anything,” she says of her request to join HEDP on her application to MIT’s Department of Physics. “And then, somehow, they reached out to me. I told them I’m willing to learn about plasma. I didn’t know anything about it.”

      What she did know was that the HEDP group collaborates with other U.S. laboratories on an approach to creating fusion energy known as inertial confinement fusion (ICF). One version of the technique, known as direct-drive ICF, aims multiple laser beams symmetrically onto a spherical capsule filled with nuclear fuel. The other, indirect-drive ICF, instead aims multiple lasers beams into a gold cylindrical cavity called a hohlraum, within which the spherical fuel capsule is positioned. The laser beams are configured to hit the inner hohlraum wall, generating a “bath” of X-rays, which in turn compress the fuel capsule.

      Imploding the capsule generates intense fusion energy within a tiny fraction of a second (an order of tens of picoseconds). In August 2021, the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) used this method to produce an historic fusion yield of 1.3 megajoules, putting researchers within reach of “ignition,” the point where the self-sustained fusion burn spreads into the surrounding fuel, leading to a high fusion-energy gain.  

      Joining the group just a month before this long-sought success, Dannhoff was impressed more with the response of her new teammates and the ICF community than with the scientific milestone. “I got a better appreciation for people who had spent their entire careers working on this project, just chugging along doing their best, ignoring the naysayers. I was excited for the people.”

      Dannhoff is now working toward extending the success of NIF and other ICF experiments, like the OMEGA laser at the University of Rochester’s Laboratory for Laser Energetics. Under the supervision of Senior Research Scientist Chikang Li, she is studying what happens to the flow of plasma within the hohlraum cavity during indirect ICF experiments, particularly for hohlraums with inner-wall aerogel foam linings. Experiments, over the last decade, have shown just how excruciatingly precise the symmetry in ICF targets must be. The more symmetric the X-ray drive, the more effective the implosion, and it is possible that these foam linings will improve the X-ray symmetry and drive efficiency.

      Dannhoff is specifically interested in studying the behavior of silicon and tantalum-based foam liners. She is as concerned with the challenges of the people at General Atomics (GA) and LLNL who are creating these targets as she is with the scientific outcome.

      “I just had a meeting with GA yesterday,” she notes. “And it’s a really tricky process. It’s kind of pushing the boundaries of what is doable at the moment. I got a much better sense of how demanding this project is for them, how much we’re asking of them.”

      What excites Dannhoff is the teamwork she observes, both at MIT and between ICF institutions around the United States. With roughly 10 graduate students and postdocs down the hall, each with an assigned lead role in lab management, she knows she can consult an expert on almost any question. And collaborators across the country are just an email away. “Any information that people can give you, they will give you, and usually very freely,” she notes. “Everyone just wants to see this work.”

      That Dannhoff is a natural team player is also evidenced in her hobbies. A hockey goalie, she prioritizes playing with MIT’s intramural teams, “because goalies are a little hard to come by. I just play with whoever needs a goalie on that night, and it’s a lot of fun.”

      She is also a member of the radio community, a fellowship she first embraced at Case Western — a moment she describes as a turning point in her life. “I literally don’t know who I would be today if I hadn’t figured out radio is something I’m interested in,” she admits. The MIT Radio Society provided the perfect landing pad for her arrival in Cambridge, full of the kinds of supportive, interesting, knowledgeable students she had befriended as an undergraduate. She credits radio with helping her realize that she could make her greatest contributions to science by focusing on engineering.

      Danhoff gets philosophical as she marvels at the invisible waves that surround us.

      “Not just radio waves: every wave,” she asserts. “The voice is the everywhere. Music, signal, space phenomena: it’s always around. And all we have to do is make the right little device and have the right circuit elements put in the right order to unmix and mix the signals and amplify them. And bada-bing, bada-boom, we’re talking with the universe.”

      “Maybe that epitomizes physics to me,” she adds. “We’re trying to listen to the universe, and it’s talking to us. We just have to come up with the right tools and hear what it’s trying to say.” More

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      in Environment

      MADMEC winner identifies sustainable greenhouse-cooling materials

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      The winners of this year’s MADMEC competition identified a class of materials that could offer a more efficient way to keep greenhouses cool.

      After Covid-19 put the materials science competition on pause for two years, on Tuesday SmartClime, a team made up of three MIT graduate students, took home the first place, $10,000 prize.

      The team showed that a type of material that changes color in response to an electric voltage could reduce energy usage and save money if coated onto the panes of glass in greenhouses.

      “This project came out of our love of gardening,” said SmartClime team member and PhD candidate Isabella Caruso in the winning presentation. “Greenhouses let you grow things year-round, even in New England, but even greenhouse pros need to use heating furnaces in the winter and ventilation in the summer. All of that can be very labor- and energy-intensive.”

      Current options to keep greenhouses cool include traditional air conditioning units, venting and fans, and simple cloth. To develop a better solution, the team looked through scientific papers to find materials with the right climate control properties.

      Two classes of materials that looked promising were thermochromic coatings, which change color based on temperature, and electrochromic solutions, which change color based on electric voltage.

      Creating both the thermochromic and electrochromic solutions required the team to assemble nanoparticles and spin-coat them onto glass substrates. In lab tests, the electrochromic material performed well, turning a deep bluish hue to reduce the heat coming into the greenhouse while also letting in enough light for plants. Specifically, the electrochromic cell kept its test box about 1 to 3 degrees Celsius cooler than the test box coated in regular glass.

      The team estimated that greenhouse owners could make back the added costs of the electrochromic paneling through savings on other climate-control measures. Additional benefits of using the material include reducing heat-related crop losses, increasing crop yields, and reducing water requirements.

      Hosted by MIT’s Department of Materials Science and Engineering (DMSE), the competition was the culmination of team projects that began last spring and included a series of design challenges throughout the summer. Each team received guidance, access to equipment and labs, and up to $1,000 in funding to build and test their prototypes.

      “It’s great to be back and to have everyone here in person,” Mike Tarkanian, a senior lecturer in DMSE and coordinator of MADMEC, said at the event. “I’ve enjoyed getting back to normal, doing the design challenges over the summer and celebrating with everyone here today.”

      The second-place prize was split between YarnZ, which identified a nanofiber yarn that is more sustainable than traditional textile fibers, and WasteAway, which has developed a waste bin monitoring device that can identify the types of items thrown into trash and recycling bins and flag misplaced items.

      YarnZ (which stands for Yarns Are Really NanofiberZ), developed a nanofiber yarn that is more degradable than traditional microfiber yarns without sacrificing on performance.

      A large chunk of the waste and emissions in the clothing industry come from polyester, a slow-degrading polymer that requires an energy-intensive melt spinning process before it’s spun into the fibers of our clothes.

      “The biggest thing I want to impress upon you today is that the textile industry is a major greenhouse gas-producing entity and also produces a huge amount of waste,” YarnZ member and PhD candidate Natalie Mamrol said in the presentation.

      To replace polyester, the team developed a continuous process in which a type of nanofiber film collects in a water bath before being twisted into yarn. In subsequent tests, the nanofiber-based yarn degraded more quicky than traditional microfibers and showed comparable durability. YarnZ believes this early data should encourage others to explore nanofibers as a viable replacement in the clothing industry and to invest in scaling the approach for industrial settings.

      WasteAway’s system includes a camera that sits on top of trash bins and uses artificial intelligence to recognize items that people throw away.

      Of the 300 million tons of waste generated in the U.S. each year, more than half ends up in landfills. A lot of that waste could have been composted or recycled but was misplaced during disposal.

      “When someone throws something into the bin, our sensor detects the motion and captures an image,” explains WasteAway’s Melissa Stok, an undergraduate at MIT. “Those images are then processed by our machine-learning algorithm to find contamination.”

      Each device costs less than $30, and the team says that cost could go down as parts are bought at larger scales. The insights gleaned from the device could help waste management officials identify contaminated trash piles as well as inform education efforts by revealing common mistakes people make.

      Overall, Tarkanian believes the competition was a success not only because of the final results, but because of the experience the students got throughout the MADMEC program, which included several smaller, hands-on competitions involving laser cutters, 3-D printers, soldering irons, and other equipment many students said they had never used before.

      “They end up getting into the lab through these design challenges, which have them compete in various engineering tasks,” Tarkanian says. “It helps them get comfortable designing and prototyping, and they often end up using those tools in their research later.” More

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      in Energy

      Simulating neutron behavior in nuclear reactors

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      Amelia Trainer applied to MIT because she lost a bet.

      As part of what the fourth-year nuclear science and engineering (NSE) doctoral student labels her “teenage rebellious phase,” Trainer was quite convinced she would just be wasting the application fee were she to submit an application. She wasn’t even “super sure” she wanted to go to college. But a high-school friend was convinced Trainer would get into a “top school” if she only applied. A bet followed: If Trainer lost, she would have to apply to MIT. Trainer lost — and is glad she did.

      Growing up in Daytona Beach, Florida, good grades were Trainer’s thing. Seeing friends participate in interschool math competitions, Trainer decided she would tag along and soon found she loved them. She remembers being adept at reading the room: If teams were especially struggling over a problem, Trainer figured the answer had to be something easy, like zero or one. “The hardest problems would usually have the most goofball answers,” she laughs.

      Simulating neutron behavior

      As a doctoral student, hard problems in math, specifically computational reactor physics, continue to be Trainer’s forte.

      Her research, under the guidance of Professor Benoit Forget in MIT NSE’s Computational Reactor Physics Group (CRPG), focuses on modeling complicated neutron behavior in reactors. Simulation helps forecast the behavior of reactors before millions of dollars sink into development of a potentially uneconomical unit. Using simulations, Trainer can see “where the neutrons are going, how much heat is being produced, and how much power the reactor can generate.” Her research helps form the foundation for the next generation of nuclear power plants.

      To simulate neutron behavior inside of a nuclear reactor, you first need to know how neutrons will interact with the various materials inside the system. These neutrons can have wildly different energies, thereby making them susceptible to different physical phenomena. For the entirety of her graduate studies, Trainer has been primarily interested in the physics regarding slow-moving neutrons and their scattering behavior.

      When a slow neutron scatters off of a material, it can induce or cancel out molecular vibrations between the material’s atoms. The effect that material vibrations can have on neutron energies, and thereby on reactor behavior, has been heavily approximated over the years. Trainer is primarily interested in chipping away at these approximations by creating scattering data for materials that have historically been misrepresented and by exploring new techniques for preparing slow-neutron scattering data.

      Trainer remembers waiting for a simulation to complete in the early days of the Covid-19 pandemic, when she discovered a way to predict neutron behavior with limited input data. Traditionally, “people have to store large tables of what neutrons will do under specific circumstances,” she says. “I’m really happy about it because it’s this really cool method of sampling what your neutron does from very little information,” Trainer says.

      Amelia Trainer — Modeling complicated neutron behavior in nuclear reactors

      As part of her research, Trainer often works closely with two software packages: OpenMC and NJOY. OpenMC is a Monte Carlo neutron transport simulation code that was developed in the CRPG and is used to simulate neutron behavior in reactor systems. NJOY is a nuclear data processing tool, and is used to create, augment, and prepare material data that is fed into tools like OpenMC. By editing both these codes to her specifications, Trainer is able to observe the effect that “upstream” material data has on the “downstream” reactor calculations. Through this, she hopes to identify additional problems: approximations that could lead to a noticeable misrepresentation of the physics.

      A love of geometry and poetry

      Trainer discovered the coolness of science as a child. Her mother, who cares for indoor plants and runs multiple greenhouses, and her father, a blacksmith and farrier, who explored materials science through his craft, were self-taught inspirations.

      Trainer’s father urged his daughter to learn and pursue any topics that she found exciting and encouraged her to read poems from “Calvin and Hobbes” out loud when she struggled with a speech impediment in early childhood. Reading the same passages every day helped her memorize them. “The natural manifestation of that extended into [a love of] poetry,” Trainer says.

      A love of poetry, combined with Trainer’s propensity for fun, led her to compose an ode to pi as part of an MIT-sponsored event for alumni. “I was really only in it for the cupcake,” she laughs. (Participants received an indulgent treat).

      Play video

      MIT Matters: A Love Poem to Pi

      Computations and nuclear science

      After being accepted at MIT, Trainer knew she wanted to study in a field that would take her skills at the levels they were at — “my math skills were pretty underdeveloped in the grand scheme of things,” she says. An open-house weekend at MIT, where she met with faculty from the NSE department, and the opportunity to contribute to a discipline working toward clean energy, cemented Trainer’s decision to join NSE.

      As a high schooler, Trainer won a scholarship to Embry-Riddle Aeronautical University to learn computer coding and knew computational physics might be more aligned with her interests. After she joined MIT as an undergraduate student in 2014, she realized that the CRPG, with its focus on coding and modeling, might be a good fit. Fortunately, a graduate student from Forget’s team welcomed Trainer’s enthusiasm for research even as an undergraduate first-year. She has stayed with the lab ever since. 

      Research internships at Los Alamos National Laboratory, the creators of NJOY, have furthered Trainer’s enthusiasm for modeling and computational physics. She met a Los Alamos scientist after he presented a talk at MIT and it snowballed into a collaboration where she could work on parts of the NJOY code. “It became a really cool collaboration which led me into a deep dive into physics and data preparation techniques, which was just so fulfilling,” Trainer says. As for what’s next, Trainer was awarded the Rickover fellowship in nuclear engineering by the the Department of Energy’s Naval Reactors Division and will join the program in Pittsburgh after she graduates.

      For many years, Trainer’s cats, Jacques and Monster, have been a constant companion. “Neutrons, computers, and cats, that’s my personality,” she laughs. Work continues to fuel her passion. To borrow a favorite phrase from Spaceman Spiff, Trainer’s favorite “Calvin” avatar, Trainer’s approach to research has invariably been: “Another day, another mind-boggling adventure.” More

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      in Energy

      Building better batteries, faster

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      To help combat climate change, many car manufacturers are racing to add more electric vehicles in their lineups. But to convince prospective buyers, manufacturers need to improve how far these cars can go on a single charge. One of their main challenges? Figuring out how to make extremely powerful but lightweight batteries.

      Typically, however, it takes decades for scientists to thoroughly test new battery materials, says Pablo Leon, an MIT graduate student in materials science. To accelerate this process, Leon is developing a machine-learning tool for scientists to automate one of the most time-consuming, yet key, steps in evaluating battery materials.

      With his tool in hand, Leon plans to help search for new materials to enable the development of powerful and lightweight batteries. Such batteries would not only improve the range of EVs, but they could also unlock potential in other high-power systems, such as solar energy systems that continuously deliver power, even at night.

      From a young age, Leon knew he wanted to pursue a PhD, hoping to one day become a professor of engineering, like his father. Growing up in College Station, Texas, home to Texas A&M University, where his father worked, many of Leon’s friends also had parents who were professors or affiliated with the university. Meanwhile, his mom worked outside the university, as a family counselor in a neighboring city.

      In college, Leon followed in his father’s and older brother’s footsteps to become a mechanical engineer, earning his bachelor’s degree at Texas A&M. There, he learned how to model the behaviors of mechanical systems, such as a metal spring’s stiffness. But he wanted to delve deeper, down to the level of atoms, to understand exactly where these behaviors come from.

      So, when Leon applied to graduate school at MIT, he switched fields to materials science, hoping to satisfy his curiosity. But the transition to a different field was “a really hard process,” Leon says, as he rushed to catch up to his peers.

      To help with the transition, Leon sought out a congenial research advisor and found one in Rafael Gómez-Bombarelli, an assistant professor in the Department of Materials Science and Engineering (DMSE). “Because he’s from Spain and my parents are Peruvian, there’s a cultural ease with the way we talk,” Leon says. According to Gómez-Bombarelli, sometimes the two of them even discuss research in Spanish — a “rare treat.” That connection has empowered Leon to freely brainstorm ideas or talk through concerns with his advisor, enabling him to make significant progress in his research.

      Leveraging machine learning to research battery materials

      Scientists investigating new battery materials generally use computer simulations to understand how different combinations of materials perform. These simulations act as virtual microscopes for batteries, zooming in to see how materials interact at an atomic level. With these details, scientists can understand why certain combinations do better, guiding their search for high-performing materials.

      But building accurate computer simulations is extremely time-intensive, taking years and sometimes even decades. “You need to know how every atom interacts with every other atom in your system,” Leon says. To create a computer model of these interactions, scientists first make a rough guess at a model using complex quantum mechanics calculations. They then compare the model with results from real-life experiments, manually tweaking different parts of the model, including the distances between atoms and the strength of chemical bonds, until the simulation matches real life.

      With well-studied battery materials, the simulation process is somewhat easier. Scientists can buy simulation software that includes pre-made models, Leon says, but these models often have errors and still require additional tweaking.

      To build accurate computer models more quickly, Leon is developing a machine-learning-based tool that can efficiently guide the trial-and-error process. “The hope with our machine learning framework is to not have to rely on proprietary models or do any hand-tuning,” he says. Leon has verified that for well-studied materials, his tool is as accurate as the manual method for building models.

      With this system, scientists will have a single, standardized approach for building accurate models in lieu of the patchwork of approaches currently in place, Leon says.

      Leon’s tool comes at an opportune time, when many scientists are investigating a new paradigm of batteries: solid-state batteries. Compared to traditional batteries, which contain liquid electrolytes, solid-state batteries are safer, lighter, and easier to manufacture. But creating versions of these batteries that are powerful enough for EVs or renewable energy storage is challenging.

      This is largely because in battery chemistry, ions dislike flowing through solids and instead prefer liquids, in which atoms are spaced further apart. Still, scientists believe that with the right combination of materials, solid-state batteries can provide enough electricity for high-power systems, such as EVs. 

      Leon plans to use his machine-learning tool to help look for good solid-state battery materials more quickly. After he finds some powerful candidates in simulations, he’ll work with other scientists to test out the new materials in real-world experiments.

      Helping students navigate graduate school

      To get to where he is today, doing exciting and impactful research, Leon credits his community of family and mentors. Because of his upbringing, Leon knew early on which steps he would need to take to get into graduate school and work toward becoming a professor. And he appreciates the privilege of his position, even more so as a Peruvian American, given that many Latino students are less likely to have access to the same resources. “I understand the academic pipeline in a way that I think a lot of minority groups in academia don’t,” he says.

      Now, Leon is helping prospective graduate students from underrepresented backgrounds navigate the pipeline through the DMSE Application Assistance Program. Each fall, he mentors applicants for the DMSE PhD program at MIT, providing feedback on their applications and resumes. The assistance program is student-run and separate from the admissions process.

      Knowing firsthand how invaluable mentorship is from his relationship with his advisor, Leon is also heavily involved in mentoring junior PhD students in his department. This past year, he served as the academic chair on his department’s graduate student organization, the Graduate Materials Council. With MIT still experiencing disruptions from Covid-19, Leon noticed a problem with student cohesiveness. “I realized that traditional [informal] modes of communication across [incoming class] years had been cut off,” he says, making it harder for junior students to get advice from their senior peers. “They didn’t have any community to fall back on.”

      To help fix this problem, Leon served as a go-to mentor for many junior students. He helped second-year PhD students prepare for their doctoral qualification exam, an often-stressful rite of passage. He also hosted seminars for first-year students to teach them how to make the most of their classes and help them acclimate to the department’s fast-paced classes. For fun, Leon organized an axe-throwing event to further facilitate student cameraderie.

      Leon’s efforts were met with success. Now, “newer students are building back the community,” he says, “so I feel like I can take a step back” from being academic chair. He will instead continue mentoring junior students through other programs within the department. He also plans to extend his community-building efforts among faculty and students, facilitating opportunities for students to find good mentors and work on impactful research. With these efforts, Leon hopes to help others along the academic pipeline that he’s become familiar with, journeying together over their PhDs. More