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      in Environment

      Five MIT PhD students awarded 2022 J-WAFS fellowships for water and food solutions

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      The Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) recently announced the selection of its 2022-23 cohort of graduate fellows. Two students were named Rasikbhai L. Meswani Fellows for Water Solutions and three students were named J-WAFS Graduate Student Fellows. All five fellows will receive full tuition and a stipend for one semester, and J-WAFS will support the students throughout the 2022-23 academic year by providing networking, mentorship, and opportunities to showcase their research.

      New this year, fellowship nominations were open not only to students pursuing water research, but food-related research as well. The five students selected were chosen for their commitment to solutions-based research that aims to alleviate problems such as water supply or purification, food security, or agriculture. Their projects exemplify the wide range of research that J-WAFS supports, from enhancing nutrition through improved methods to deliver micronutrients to developing high-performance drip irrigation technology. The strong applicant pool reflects the passion MIT students have to address the water and food crises currently facing the planet.

      “This year’s fellows are drawn from a dynamic and engaged community across the Institute whose creativity and ingenuity are pushing forward transformational water and food solutions,” says J-WAFS executive director Renee J. Robins. “We congratulate these students as we recognize their outstanding achievements and their promise as up-and-coming leaders in global water and food sectors.”

      2022-23 Rasikbhai L. Meswani Fellows for Water SolutionsThe Rasikbhai L. Meswani Fellowship for Water Solutions is a fellowship for students pursuing water-related research at MIT. The Rasikbhai L. Meswani Fellowship for Water Solutions was made possible by a generous gift from Elina and Nikhil Meswani and family.

      Aditya Ghodgaonkar is a PhD candidate in the Department of Mechanical Engineering at MIT, where he works in the Global Engineering and Research (GEAR) Lab under Professor Amos Winter. Ghodgaonkar received a bachelor’s degree in mechanical engineering from the RV College of Engineering in India. He then moved to the United States and received a master’s degree in mechanical engineering from Purdue University.Ghodgaonkar is currently designing hydraulic components for drip irrigation that could support the development of water-efficient irrigation systems that are off-grid, inexpensive, and low-maintenance. He has focused on designing drip irrigation emitters that are resistant to clogging, seeking inspiration about flow regulation from marine fauna such as manta rays, as well as turbomachinery concepts. Ghodgaonkar notes that clogging is currently an expensive technical challenge to diagnose, mitigate, and resolve. With an eye on hundreds of millions of farms in developing countries, he aims to bring the benefits of irrigation technology to even the poorest farmers.Outside of his research, Ghodgaonkar is a mentor in MIT Makerworks and has been a teaching assistant for classes such as 2.007 (Design and Manufacturing I). He also helped organize the annual MIT Water Summit last fall.

      Devashish Gokhale is a PhD candidate advised by Professor Patrick Doyle in the Department of Chemical Engineering. He received a bachelor’s degree in chemical engineering from the Indian Institute of Technology Madras, where he researched fluid flow in energy-efficient pumps. Gokhale’s commitment to global water security stemmed from his experience growing up in India, where water sources are threatened by population growth, industrialization, and climate change.As a researcher in the Doyle group, Devashish is developing sustainable and reusable materials for water treatment, with a focus on the elimination of emerging contaminants and other micropollutants from water through cost-effective processes. Many of these contaminants are carcinogens or endocrine disruptors, posing significant threats to both humans and animals. His advisor notes that Devashish was the first researcher in the Doyle group to work on water purification, bringing his passion for the topic to the lab.Gokhale’s research won an award for potential scalability in last year’s J-WAFS World Water Day competition. He also serves as the lecture series chair in the MIT Water Club.

      2022-23 J-WAFS Graduate Student FellowsThe J-WAFS Fellowship for Water and Food Solutions is funded by the J-WAFS Research Affiliate Program, which offers companies the opportunity to collaborate with MIT on water and food research. A portion of each research affiliate’s fees supports this fellowship. The program is central to J-WAFS’ efforts to engage across sector and disciplinary boundaries in solving real-world problems. Currently, there are two J-WAFS Research Affiliates: Xylem, Inc., a water technology company, and GoAigua, a company leading the digital transformation of the water industry.

      James Zhang is a PhD candidate in the Department of Mechanical Engineering at MIT, where he has worked in the NanoEngineering Laboratory with Professor Gang Chen since 2019. As an undergraduate at Carnegie Mellon University, he double majored in mechanical engineering and engineering public policy. He then received a master’s degree in mechanical engineering from MIT. In addition to working in the NanoEngineering Laboratory, James has also worked in the Zhao Laboratory and in the Boriskina Research Group at MIT.Zhang is developing a technology that uses light-induced evaporation to clean water. He is currently investigating the fundamental properties of how light interacts with brackish water surfaces. With strong theoretical as well as experimental components, his research could lead to innovations in desalinating brackish water at high energy efficiencies. Outside of his research, Zhang has served as a student moderator for the MIT International Colloquia on Thermal Innovations.

      Katharina Fransen is a PhD candidate advised by Professor Bradley Olsen in the Department of Chemical Engineering at MIT. She received a bachelor’s degree in chemical engineering from the University of Minnesota, where she was involved in the Society of Women Engineers. Fransen is motivated by the challenge of protecting the most vulnerable global communities from the large quantities of plastic waste associated with traditional food packaging materials. As a researcher in the Olsen Lab, Fransen is developing new plastics that are biologically-based and biodegradable, so they can degrade in the environment instead of polluting communities with plastic waste. These polymers are also optimized for food packaging applications to keep food fresher for longer, preventing food waste.Outside of her research, Fransen is involved in Diversity in Chemical Engineering as the coordinator for the graduate application mentorship program for underrepresented groups. She is also an active member of Graduate Womxn in ChemE and mentors an Undergraduate Research Opportunities Program student.

      Linzixuan (Rhoda) Zhang is a PhD candidate advised by Professor Robert Langer and Ana Jaklenec in the Department of Chemical Engineering at MIT. She received a bachelor’s degree in chemical engineering from the University of Illinois at Urbana-Champaign, where she researched how to genetically engineer microorganisms for the efficient production of advanced biofuels and chemicals.Zhang is currently developing a micronutrient delivery platform that fortifies foods with essential vitamins and nutrients. She has helped develop a group of biodegradable polymers that can stabilize micronutrients under harsh conditions, enabling local food companies to fortify food with essential vitamins. This work aims to tackle a hidden crisis in low- and middle-income countries, where a chronic lack of essential micronutrients affects an estimated 2 billion people.Zhang is also working on the development of self-boosting vaccines to promote more widespread vaccine access and serves as a research mentor in the Langer Lab. More

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      in Environment

      Architecture isn’t just for humans anymore

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      In a rural valley of northwestern Nevada, home to stretches of wetlands, sagebrush-grassland, and dozens of natural springs, is a 3,800-acre parcel of off-grid land known as Fly Ranch. Owned by Burning Man, the community that yearly transforms the neighboring playa into a colorful free-wheeling temporary city, Fly Ranch is part of a long-term project to extend the festival’s experimental ethos beyond the one-week event. In 2018, the group, in conjunction with The Land Art Generator Initiative, invited proposals for sustainable systems for energy, water, food, shelter, and regenerative waste management on the site. 

      For recent MIT alumni Zhicheng Xu MArch ’22 and Mengqi Moon He SMArchS ’20, Fly Ranch presented a new challenge. Xu and He, who have backgrounds in landscape design, urbanism, and architecture, had been in the process of researching the use of timber as a building material, and thought the competition would be a good opportunity to experiment and showcase some of their initial research. “But because of our MIT education, we approached the problem with a very critical lens,” says Xu, “We were asking ourselves: Who are we designing for? What do we mean by shelter? Sheltering whom?” 

      Architecture for other-than-human worlds

      Their winning proposal, “Lodgers,” selected among 185 entries and currently on view at the Weisner Student Art Gallery, asks how to design a structure that will accommodate not only the land’s human inhabitants, but also the over 100 plant and animal species that call the desert home. In other words, what would an architecture look like that centered not only human needs, but also those of the broader ecosystem? 

      Developing the project during the pandemic lockdowns, Xu and He pored over a long list of hundreds of local plants and animals — from red-tailed hawks to desert rats to bullfrogs — and designed the project with these species in mind. Combining new computational tools with the traditional Western Shoshone and Northern Paiute designs found in brush shelters and woven baskets, the thatched organic structures called “lodgers” feature bee towers, nesting platforms for birds, sugar-glazed logs for breeding beetle larvae, and composting toilets and environmental education classrooms for humans. 

      But it wasn’t until they visited Fly Ranch, in the spring of 2021, that Xu and He’s understanding of the project deepened. For several nights, they camped onsite with other competition finalists, alongside park rangers and longtime Burners, eating community meals together and learning first-hand the complexities of the desert. At one point during the trip, they were caught in a sandstorm while driving a trailer-load of supplies down a dirt road. The experience, they say, was an important lesson in humility, and how such extremes made the landscape what it was. “That’s why we later came to the term ‘coping with the friction’ because it’s always there,” He says, “There’s no solution.” Xu adds, “The different elements from the land — the water, the heat, the sound, the wind — are the elements we have to cope with in the project. Those little moments made us realize we need to reposition ourselves, stay humble, and try to understand the land.” 

      Leave no trace

      While the deserts of the American West have long been vulnerable to human hubris — from large-scale military procedures to mining operations that have left deep scars on the landscape — Xu and He designed the “lodgers” to leave a light footprint. Instead of viewing buildings as permanent solutions, with the environment perceived as an obstacle to be overcome, Xu and He see their project as a “temporary inhabitant.” 

      To reduce carbon emissions, their goal was to adopt low-cost, low-tech, recycled materials that could be used without the need for special training or heavy equipment, so that the construction itself could be open to everyone in the community. In addition to scrap wood collected onsite, the project uses two-by-four lumber, among the most common and cheapest materials in American construction, and thatching for the facades created from the dry reeds and bulrush that grow abundantly in the region. If the structures are shut down, the use of renewable materials allows them to decompose naturally. 

      Fly Ranch at MIT 

      Now, the MIT community has the opportunity to experience part of the Nevada desert — and be part of the process of participatory design. “We are very fortunate to be funded by the Council of the Arts at MIT,” says Xu. “With that funding, we were able to expand the team, so the format of the exhibition was more democratic than just designing and building.” With the help of their classmates Calvin Zhong ’18 and Wuyahuang Li SMArchS ’21, Xu and He have brought their proposal to life. The ambitious immersive installation includes architectural models, field recordings, projections, and artifacts such as the skeletons of turtles and fish collected at Fly Ranch. Inside the structure is a large communal table, where Xu and He hope to host workshops and conversations to encourage more dialogue and collaboration. Having learned from the design build, Xu and He are now collecting feedback from MIT professors and colleagues to bring the project to the next level. In the fall, they will debut the “lodgers” at the Lisbon Architectural Triennale, and soon hope to build a prototype at Fly Ranch itself. 

      The structures, they hope, will inspire greater reflection on our entanglements with the other-than-human world, and the possibilities of an architecture designed to be impermanent. Humans, after all, are often only “occasional guests” in this landscape, and part of the greater cycles of emergence and decay. “To us, it’s a beautiful expression of how different species are entangled on the land. And us as humans is just another tiny piece in this entanglement,” says Xu. 

      Established as a gift from the MIT Class of 1983, the Wiesner Gallery honors the former president of MIT, Jerome Wiesner, for his support of the arts at the Institute. The gallery was fully renovated in fall 2016, thanks in part to the generosity of Harold ’44 and Arlene Schnitzer and the Council for the Arts at MIT, and now also serves as a central meeting space for MIT Student Arts Programming including the START Studio, Creative Arts Competition, Student Arts Advisory Board, and Arts Scholars. “Lodgers: Friction Between Neighbors” is on view in the Wiesner Student Art Gallery through April 29, and was funded in part by the Council for the Arts at MIT, a group of alumni and friends with a strong commitment to the arts and serving the MIT community. More

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      in Energy

      A better way to separate gases

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      Industrial processes for chemical separations, including natural gas purification and the production of oxygen and nitrogen for medical or industrial uses, are collectively responsible for about 15 percent of the world’s energy use. They also contribute a corresponding amount to the world’s greenhouse gas emissions. Now, researchers at MIT and Stanford University have developed a new kind of membrane for carrying out these separation processes with roughly 1/10 the energy use and emissions.

      Using membranes for separation of chemicals is known to be much more efficient than processes such as distillation or absorption, but there has always been a tradeoff between permeability — how fast gases can penetrate through the material — and selectivity — the ability to let the desired molecules pass through while blocking all others. The new family of membrane materials, based on “hydrocarbon ladder” polymers, overcomes that tradeoff, providing both high permeability and extremely good selectivity, the researchers say.

      The findings are reported today in the journal Science, in a paper by Yan Xia, an associate professor of chemistry at Stanford; Zachary Smith, an assistant professor of chemical engineering at MIT; Ingo Pinnau, a professor at King Abdullah University of Science and Technology, and five others.

      Gas separation is an important and widespread industrial process whose uses include removing impurities and undesired compounds from natural gas or biogas, separating oxygen and nitrogen from air for medical and industrial purposes, separating carbon dioxide from other gases for carbon capture, and producing hydrogen for use as a carbon-free transportation fuel. The new ladder polymer membranes show promise for drastically improving the performance of such separation processes. For example, separating carbon dioxide from methane, these new membranes have five times the selectivity and 100 times the permeability of existing cellulosic membranes for that purpose. Similarly, they are 100 times more permeable and three times as selective for separating hydrogen gas from methane.

      The new type of polymers, developed over the last several years by the Xia lab, are referred to as ladder polymers because they are formed from double strands connected by rung-like bonds, and these linkages provide a high degree of rigidity and stability to the polymer material. These ladder polymers are synthesized via an efficient and selective chemistry the Xia lab developed called CANAL, an acronym for catalytic arene-norbornene annulation, which stitches readily available chemicals into ladder structures with hundreds or even thousands of rungs. The polymers are synthesized in a solution, where they form rigid and kinked ribbon-like strands that can easily be made into a thin sheet with sub-nanometer-scale pores by using industrially available polymer casting processes. The sizes of the resulting pores can be tuned through the choice of the specific hydrocarbon starting compounds. “This chemistry and choice of chemical building blocks allowed us to make very rigid ladder polymers with different configurations,” Xia says.

      To apply the CANAL polymers as selective membranes, the collaboration made use of Xia’s expertise in polymers and Smith’s specialization in membrane research. Holden Lai, a former Stanford doctoral student, carried out much of the development and exploration of how their structures impact gas permeation properties. “It took us eight years from developing the new chemistry to finding the right polymer structures that bestow the high separation performance,” Xia says.

      The Xia lab spent the past several years varying the structures of CANAL polymers to understand how their structures affect their separation performance. Surprisingly, they found that adding additional kinks to their original CANAL polymers significantly improved the mechanical robustness of their membranes and boosted their selectivity  for molecules of similar sizes, such as oxygen and nitrogen gases, without losing permeability of the more permeable gas. The selectivity actually improves as the material ages. The combination of high selectivity and high permeability makes these materials outperform all other polymer materials in many gas separations, the researchers say.

      Today, 15 percent of global energy use goes into chemical separations, and these separation processes are “often based on century-old technologies,” Smith says. “They work well, but they have an enormous carbon footprint and consume massive amounts of energy. The key challenge today is trying to replace these nonsustainable processes.” Most of these processes require high temperatures for boiling and reboiling solutions, and these often are the hardest processes to electrify, he adds.

      For the separation of oxygen and nitrogen from air, the two molecules only differ in size by about 0.18 angstroms (ten-billionths of a meter), he says. To make a filter capable of separating them efficiently “is incredibly difficult to do without decreasing throughput.” But the new ladder polymers, when manufactured into membranes produce tiny pores that achieve high selectivity, he says. In some cases, 10 oxygen molecules permeate for every nitrogen, despite the razor-thin sieve needed to access this type of size selectivity. These new membrane materials have “the highest combination of permeability and selectivity of all known polymeric materials for many applications,” Smith says.

      “Because CANAL polymers are strong and ductile, and because they are soluble in certain solvents, they could be scaled for industrial deployment within a few years,” he adds. An MIT spinoff company called Osmoses, led by authors of this study, recently won the MIT $100K entrepreneurship competition and has been partly funded by The Engine to commercialize the technology.

      There are a variety of potential applications for these materials in the chemical processing industry, Smith says, including the separation of carbon dioxide from other gas mixtures as a form of emissions reduction. Another possibility is the purification of biogas fuel made from agricultural waste products in order to provide carbon-free transportation fuel. Hydrogen separation for producing a fuel or a chemical feedstock, could also be carried out efficiently, helping with the transition to a hydrogen-based economy.

      The close-knit team of researchers is continuing to refine the process to facilitate the development from laboratory to industrial scale, and to better understand the details on how the macromolecular structures and packing result in the ultrahigh selectivity. Smith says he expects this platform technology to play a role in multiple decarbonization pathways, starting with hydrogen separation and carbon capture, because there is such a pressing need for these technologies in order to transition to a carbon-free economy.

      “These are impressive new structures that have outstanding gas separation performance,” says Ryan Lively, am associate professor of chemical and biomolecular engineering at Georgia Tech, who was not involved in this work. “Importantly, this performance is improved during membrane aging and when the membranes are challenged with concentrated gas mixtures. … If they can scale these materials and fabricate membrane modules, there is significant potential practical impact.”

      The research team also included Jun Myun Ahn and Ashley Robinson at Stanford, Francesco Benedetti at MIT, now the chief executive officer at Osmoses, and Yingge Wang at King Abdullah University of Science and Technology in Saudi Arabia. The work was supported by the Stanford Natural Gas Initiative, the Sloan Research Fellowship, the U.S. Department of Energy Office of Basic Energy Sciences, and the National Science Foundation. More

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      in Energy

      Building communities, founding a startup with people in mind

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      MIT postdoc Francesco Benedetti admits he wasn’t always a star student. But the people he met along his educational journey inspired him to strive, which led him to conduct research at MIT, launch a startup, and even lead the team that won the 2021 MIT $100K Entrepreneurship Competition. Now he is determined to make sure his company, Osmoses, succeeds in boosting the energy efficiency of traditional and renewable natural gas processing, hydrogen production, and carbon capture — thus helping to address climate change.

      “I can’t be grateful enough to MIT for bringing together a community of people who want to change the world,” Benedetti says. “Now we have a technology that can solve one of the big problems of our society.”

      Benedetti and his team have developed an innovative way to separate molecules using a membrane fine enough to extract impurities such as carbon dioxide or hydrogen sulfide from raw natural gas to obtain higher-quality fuel, fulfilling a crucial need in the energy industry. “Natural gas now provides about 40 percent of the energy used to power homes and industry in the United States,” Benedetti says. Using his team’s technology to upgrade natural gas more efficiently could reduce emissions of greenhouse gases while saving enough energy to power the equivalent of 7 million additional U.S. homes for a year, he adds.

      The MIT community

      Benedetti first came to MIT in 2017 as a visiting student from the University of Bologna in Italy, where he was working on membranes for gas separation for his PhD in chemical engineering. Having completed a master’s thesis on water desalination at the University of Texas (UT) at Austin, he connected with UT alumnus Zachary P. Smith, the Robert N. Noyce Career Development Professor of Chemical Engineering at MIT, and the two discovered they shared a vision. “We found ourselves very much aligned on the need for new technology in industry to lower the energy consumption of separating components,” Benedetti says.

      Although Benedetti had always been interested in making a positive impact on the world, particularly the environment, he says it was his university studies that first sparked his interest in more efficient separation technologies. “When you study chemical engineering, you understand hundreds of ways the field can have a positive impact in the world. But we learn very early that 15 percent of the world’s energy is wasted because of inefficient chemical separation — because we still rely on centuries-old technology,” he says. Most separation processes still use heat or toxic solvents to separate components, he explains.

      Still, Benedetti says, his main drive comes from the joy of working with terrific mentors and colleagues. “It’s the people I’ve met that really inspired me to tackle the biggest challenges and find that intrinsic motivation,” he says.

      To help build his community at MIT and provide support for international students, Benedetti co-founded the MIT Visiting Student Association (VISTA) in September 2017. By February 2018, the organization had hundreds of members and official Institute recognition. In May 2018, the group won two Institute awards, including the Golden Beaver Award for enhancing the campus environment. “VISTA gave me a sense of belonging; I loved it,” Benedetti says.

      Membrane technology

      Benedetti also published two papers on membrane research during his stint as a visiting student at MIT, so he was delighted to return in 2019 for postdoctoral work through the MIT Energy Initiative, where he was a 2019-20 ExxonMobil-MIT Energy Fellow. “I came back because the research was extremely exciting, but also because I got extremely passionate about the energy I found on campus and with the people,” he says.

      Returning to MIT enabled Benedetti to continue his work with Smith and Holden Lai, both of whom helped co-found Osmoses. Lai, a recent Stanford PhD in chemistry who was also a visiting student at MIT in 2018, is now the chief technology officer at Osmoses. Co-founder Katherine Mizrahi Rodriguez ’17, an MIT PhD candidate, joined the team more recently.

      Together, the Osmoses team has developed polymer membranes with microporosities capable of filtering gases by separating out molecules that differ by as little as a fraction of an angstrom — a unit of length equal to one hundred-millionth of a centimeter. “We can get up to five times higher selectivity than commercially available technology for methane upgrading, and this has been observed operating the membranes in industrially relevant environments,” Benedetti says.

      Today, methane upgrading — removing carbon dioxide (CO2) from raw natural gas to obtain a higher-grade fuel — is often accomplished using amine absorption, a process that uses toxic solvents to capture CO2 and burns methane to fuel the regeneration of those solvents for reuse. Using Osmoses’ filters would eliminate the need for such solvents while reducing CO2 emissions by up to 16 million metric tons per year in the United States alone, Benedetti says.

      The technology has a wide range of applications — in oxygen and nitrogen generation, hydrogen purification, and carbon capture, for example — but Osmoses plans to start with the $5 billion market for natural gas upgrading because the need to bring innovation and sustainability to that space is urgent, says Benedetti, who received guidance in bringing technology to market from MIT’s Deshpande Center for Technological Innovation. The Osmoses team has also received support from the MIT Sandbox Innovation Fund Program.

      The next step for the startup is to build an industrial-scale prototype, and Benedetti says the company got a huge boost toward that goal in May when it won the MIT $100K Entrepreneurship Competition, a student-run contest that has launched more than 160 companies since it began in 1990. Ninety teams began the competition by pitching their startup ideas; 20 received mentorship and development funding; then eight finalists presented business plans to compete for the $100,000 prize. “Because of this, we’re getting a lot of interest from venture capital firms, investors, companies, corporate funds, et cetera, that want to partner with us or to use our product,” he says. In June, the Osmoses team received a two-year Activate Fellowship, which will support moving its research to market; in October, it won the Northeast Regional and Carbon Sequestration Prizes at the Cleantech Open Accelerator; and in November, the team closed a $3 million pre-seed round of financing.

      FAIL!

      Naturally, Benedetti hopes Osmoses is on the path to success, but he wants everyone to know that there is no shame in failures that come from best efforts. He admits it took him three years longer than usual to finish his undergraduate and master’s degrees, and he says, “I have experienced the pressure you feel when society judges you like a book by its cover and how much a lack of inspired leaders and a supportive environment can kill creativity and the will to try.”

      That’s why in 2018 he, along with other MIT students and VISTA members, started FAIL!–Inspiring Resilience, an organization that provides a platform for sharing unfiltered stories and the lessons leaders have gleaned from failure. “We wanted to help de-stigmatize failure, appreciate vulnerabilities, and inspire humble leadership, eventually creating better communities,” Benedetti says. “If we can make failures, big and small, less intimidating and all-consuming, individuals with great potential will be more willing to take risks, think outside the box, and try things that may push new boundaries. In this way, more breakthrough discoveries are likely to follow, without compromising anyone’s mental health.”

      Benedetti says he will strive to create a supportive culture at Osmoses, because people are central to success. “What drives me every day is the people. I would have no story without the people around me,” he says. “The moment you lose touch with people, you lose the opportunity to create something special.”

      This article appears in the Autumn 2021 issue of Energy Futures, the magazine of the MIT Energy Initiative. More

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      in Environment

      MIT entrepreneurs think globally, act locally

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      Born and raised amid the natural beauty of the Dominican Republic, Andrés Bisonó León feels a deep motivation to help solve a problem that has been threatening the Caribbean island nation’s tourism industry, its economy, and its people.

      As Bisonó León discussed with his long-time friend and mentor, the Walter M. May and A. Hazel May Professor of Mechanical Engineering (MechE) Alexander Slocum Sr., ugly mats of toxic sargassum seaweed have been encroaching on the Dominican Republic’s pristine beaches and other beaches in the Caribbean region, and public and private organizations have fought a losing battle using expensive, environmentally damaging methods to clean it up. Slocum, who was on the U.S. Department of Energy’s Deepwater Horizon team, has extensive experience with systems that operate in the ocean.

      “In the last 10 years,” says Bisonó León, now an MBA candidate in the MIT Sloan School of Management, “sargassum, a toxic seaweed invasion, has cost the Caribbean as much as $120 million a year in cleanup and has meant a 30 to 35 percent tourism reduction, affecting not only the tourism industry, but also the environment, marine life, local economies, and human health.”

      One of Bisonó León’s discussions with Slocum took place within earshot of MechE alumnus Luke Gray ’18, SM ’20, who had worked with Slocum on other projects and was at the time was about to begin his master’s program.

      “Professor Slocum and Andrés happened to be discussing the sargassum problem in Andrés’ home country,” Gray says. “A week later I was on a plane to the DR to collect sargassum samples and survey the problem in Punta Cana. When I returned, my master’s program was underway, and I already had my thesis project!”

      Gray also had started a working partnership with Bisonó León, which both say proceeded seamlessly right from the first moment.

      “I feel that Luke right away understood the magnitude of the problem and the value we could create in the Dominican Republic and across the Caribbean by teaming up,” Bisonó León says.

      Both Bisonó León and Gray also say they felt a responsibility to work toward helping the global environment.

      “All of my major projects up until now have involved machines for climate restoration and/or adaptation,” says Gray.

      The technologies Bisonó León and Gray arrived at after 18 months of R&D were designed to provide solutions both locally and globally.

      Their Littoral Collection Module (LCM) skims sargassum seaweed off the surface of the water with nets that can be mounted on any boat. The device sits across the boat, with two large hoops holding the nets open, one on each side. As the boat travels forward, it cuts through the seaweed, which flows to the sides of the vessel and through the hoops into the nets. Effective at sweeping the seaweed from the water, the device can be employed by anyone with a boat, including local fishermen whose livelihoods have been disrupted by the seaweed’s damaging effect on tourism and the local economy.

      The sargassum can then be towed out to sea, where Bisonó León’s and Gray’s second technology can come into play. By pumping the seaweed into very deep water, where it then sinks to the bottom of the ocean, the carbon in the seaweed can be sequestered. Other methods for disposing of the seaweed generally involve putting it into landfills, where it emits greenhouse gases such as methane and carbon dioxide as it breaks down. Although some seaweed can be put to other uses, including as fertilizer, sargassum has been found to contain hard-to-remove toxic substances such as arsenic and heavy metals.

      In spring 2020, Bisonó León and Gray formed a company, SOS (Sargassum Ocean Sequestration) Carbon.

      Bisonó León says he comes from a long line of entrepreneurs who often expressed much commitment to social impact. His family has been involved in several different industries, his grandfather and great uncles having opened the first cigar factory in the Dominican Republic in 1903.

      Gray says internships with startup companies and the undergraduate projects he did with Slocum developed his interest in entrepreneurship, and his involvement with the sargassum problem only reinforced that inclination. During his master’s program, he says he became “obsessed” with finding a solution.

      “Professor Slocum let me think extremely big, and so it was almost inevitable that the distillation of our two years of work would continue in some form, and starting a company happened to be the right path. My master’s experience of taking an essentially untouched problem like sargassum and then one year later designing, building, and sending 15,000 pounds of custom equipment to test for three months on a Dominican Navy ship made me realize I had discovered a recipe I could repeat — and machine design had become my core competency,” Gray says.

      During the initial research and development of their technologies, Bisonó León and Gray raised $258,000 from 20 different organizations. Between June and December 2021, they succeeded in removing 3.5 million pounds of sargassum and secured contracts with Grupo Puntacana, which operates several tourist resorts, and with other hotels such as Club Med in Punta Cana. The company subcontracts with the association of fishermen in Punta Cana, employing 15 fishermen who operate LCMs and training 35 others to join as the operation expands.

      Their success so far demonstrates “’mens et manus’ at work,” says Slocum, referring to MIT’s motto, which is Latin for “mind and hand.” “Geeks hear about a very real problem that affects very real people who have no other option for their livelihoods, and they respond by inventing a solution so elegant that it can be readily deployed by those most hurt by the problem to address the problem.

      “The team was always focused on the numbers, from physics to finance, and did not let hype or doubts deter their determination to rationally solve this huge problem.”

      Slocum says he could predict Bisonó León and Gray would work well together “because they started out as good, smart people with complementary skills whose hearts and minds were in the right place.”

      “We are working on having a global impact to reduce millions of tons of CO2 per year,” says Bisonó León. “With training from Sloan and cross-disciplinary collaborative spirit, we will be able to further expand environmental and social impact platforms much needed in the Caribbean to be able to drive real change regionally and globally.”

      “I hope SOS Carbon can serve as a model and inspire similar entrepreneurial efforts,” Gray says. More

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      in Energy

      Tuning in to invisible waves on the JET tokamak

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      Research scientist Alex Tinguely is readjusting to Cambridge and Boston.

      As a postdoc with the Plasma Science and Fusion Center (PSFC), the MIT graduate spent the last two years in Oxford, England, a city he recalls can be traversed entirely “in the time it takes to walk from MIT to Harvard.” With its ancient stone walls, cathedrals, cobblestone streets, and winding paths, that small city was his home base for a big project: JET, a tokamak that is currently the largest operating magnetic fusion energy experiment in the world.

      Located at the Culham Center for Fusion Energy (CCFE), part of the U.K. Atomic Energy Authority, this key research center of the European Fusion Program has recently announced historic success. Using a 50-50 deuterium-tritium fuel mixture for the first time since 1997, JET established a fusion power record of 10 megawatts output over five seconds. It produced 59 megajoules of fusion energy, more than doubling the 22 megajoule record it set in 1997. As a member of the JET Team, Tinguely has overseen the measurement and instrumentation systems (diagnostics) contributed by the MIT group.

      A lucky chance

      The postdoctoral opportunity arose just as Tinguely was graduating with a PhD in physics from MIT. Managed by Professor Miklos Porkolab as the principal investigator for over 20 years, this postdoctoral program has prepared multiple young researchers for careers in fusion facilities around the world. The collaborative research provided Tinguely the chance to work on a fusion device that would be adding tritium to the usual deuterium fuel.

      Fusion, the process that fuels the sun and other stars, could provide a long-term source of carbon-free power on Earth, if it can be harnessed. For decades researchers have tried to create an artificial star in a doughnut-shaped bottle, or “tokamak,” using magnetic fields to keep the turbulent plasma fuel confined and away from the walls of its container long enough for fusion to occur.

      In his graduate student days at MIT, Tinguely worked on the PSFC’s Alcator C-Mod tokamak, now decommissioned, which, like most magnetic fusion devices, used deuterium to create the plasmas for experiments. JET, since beginning operation in 1983, has done the same, later joining a small number of facilities that added tritium, a radioactive isotope of hydrogen. While this addition increases the amount of fusion, it also creates much more radiation and activation.

      Tinguely considers himself fortunate to have been placed at JET.

      “There aren’t that many operating tokamaks in the U.S. right now,” says Tinguely, “not to mention one that would be running deuterium-tritium (DT), which hasn’t been run for over 20 years, and which would be making some really important measurements. I got a very lucky spot where I was an MIT postdoc, but I lived in Oxford, working on a very international project.”

      Strumming magnetic field lines

      The measurements that interest Tinguely are of low-frequency electromagnetic waves in tokamak plasmas. Tinguely uses an antenna diagnostic developed by MIT, EPFL Swiss Plasma Center, and CCFE to probe the so-called Alfvén eigenmodes when they are stable, before the energetic alpha particles produced by DT fusion plasmas can drive them toward instability.

      What makes MIT’s “Alfvén Eigenmode Active Diagnostic” essential is that without it researchers cannot see, or measure, stable eigenmodes. Unstable modes show up clearly as magnetic fluctuations in the data, but stable waves are invisible without prompting from the antenna. These measurements help researchers understand the physics of Alfvén waves and their potential for degrading fusion performance, providing insights that will be increasingly important for future DT fusion devices.

      Tinguely likens the diagnostic to fingers on guitar strings.

      “The magnetic field lines in the tokamak are like guitar strings. If you have nothing to give energy to the strings — or give energy to the waves of the magnetic field lines — they just sit there, they don’t do anything. The energetic plasma particles can essentially ‘play the guitar strings,’ strum the magnetic field lines of the plasma, and that’s when you can see the waves in your plasma. But if the energetic particle drive of the waves is not strong enough you won’t see them, so you need to come along and ‘pluck the strings’ with our antenna. And that’s how you learn some information about the waves.”

      Much of Tinguely’s experience on JET took place during the Covid-19 pandemic, when off-site operation and analysis were the norm. However, because the MIT diagnostic needed to be physically turned on and off, someone from Tinguely’s team needed to be on site twice a day, a routine that became even less convenient when tritium was introduced.

      “When you have deuterium and tritium, you produce a lot of neutrons. So, some of the buildings became off-limits during operation, which meant they had to be turned on really early in the morning, like 6:30 a.m., and then turned off very late at night, around 10:30 p.m.”

      Looking to the future

      Now a research scientist at the PSFC, Tinguely continues to work at JET remotely. He sometimes wishes he could again ride that train from Oxford to Culham — which he fondly remembers for its clean, comfortable efficiency — to see work colleagues and to visit local friends. The life he created for himself in England included practice and performance with the 125-year-old Oxford Bach Choir, as well as weekly dinner service at The Gatehouse, a facility that offers free support for the local homeless and low-income communities.

      “Being back is exciting too,” he says. “It’s fun to see how things have changed, how people and projects have grown, what new opportunities have arrived.”

      He refers specifically to a project that is beginning to take up more of his time: SPARC, the tokamak the PSFC supports in collaboration with Commonwealth Fusion Systems. Designed to use deuterium-tritium to make net fusion gains, SPARC will be able to use the latest research on JET to advantage. Tinguely is already exploring how his expertise with Alfvén eigenmodes can support the experiment.

      “I actually had an opportunity to do my PhD — or DPhil as they would call it — at Oxford University, but I went to MIT for grad school instead,” Tinguely reveals. “So, this is almost like closure, in a sense. I got to have my Oxford experience in the end, just in a different way, and have the MIT experience too.”

      He adds, “And I see myself being here at MIT for some time.” More

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      in Environment

      Courtney Lesoon and Elizabeth Yarina win Fulbright-Hays Scholarships

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      Two MIT doctoral students in the MIT School of Architecture and Planning have received the prestigious Fulbright-Hays Scholarship for Doctoral Dissertation Research Award. Courtney Lesoon and Elizabeth “Lizzie” Yarina are the first awardees from MIT in more than a decade.

      The fellowship provides opportunities for doctoral students to engage in full-time dissertation research abroad. The program, funded by the U.S. Department of Education, is designed to contribute to the development and improvement of the study of modern foreign languages and area studies. Applicants anticipate pursuing a teaching career in the United States following completion of their dissertation. There were 138 individuals from 47 institutions named scholars for the 2021 cycle.

      Courtney Lesoon

      Lesoon is a doctoral candidate in the Aga Khan Program for Islamic Architecture, in the History, Theory and Criticism Section of the Department of Architecture. Lesoon earned her BA from College of the Holy Cross and was a 2012-13 Fulbright U.S. Student grantee to the United Arab Emirates, where her research concerned contemporary art and emerging cultural institutions. Her dissertation is titled “Spatializing Ahl al-ʿIlm: Learning and the Rise of the Early Islamic City.” Losoon’s fieldwork will be done in Morocco, Egypt, and Turkey.

      “Courtney’s project presents an innovative idea that has not, to my knowledge, been investigated before,” says Nasser Rabbat, professor and director of the MIT Aga Khan Program. “How did the emergence and evolution of a particularly Islamic learning system affect the development of the city in the early Islamic period? Her work enriches the thinking about premodern urbanism and education everywhere by theorizing the intricate relationship between traveling, learning, and the city.”

      “I’ll be working in different manuscripts collections in Morocco, Egypt, and Turkey to investigate where and how scholars were learning inside of the early Islamic city before the formal institutionalization of higher education,” says Lesoon. “I’m interested in how learning — as a set of social practices — informed urban life. My project speaks to two different fields; Islamic urbanism and Islamic intellectual history. I’m really excited about my time on Fulbright-Hays; it will be a really fruitful time for my research and writing.”

      Before arriving at MIT, Lesoon worked as a research assistant in the Art of the Middle East Department at the Los Angeles County Museum of Art. Recently, she was awarded the 2021 Margaret B. Ševčenko Prize for “the best unpublished essay written by a junior scholar” for her paper “The Sphero-conical as Apothecary Vessel: An Argument for Dedicated Use.” Lesoon earned her MA from the University of Michigan at Ann Arbor, where her thesis investigated an 18th-century “Damascus Room” and its acquisition as a collected interior in the United States.

      Lizzie Yarina

      Yarina is a doctoral candidate in the MIT Department of Urban Studies and Planning (DUSP) and a research fellow at the MIT Norman B. Leventhal Center for Advanced Urbanism. She is presently co-editing a volume on the relationship between climate models and the built environment with a multidisciplinary team of editors and contributors. Yarina was a research scientist at the MIT Urban Risk Lab, where she was part of a team examining alternatives to the Federal Emergency Management Agency’s post-disaster housing systems; she also conducted research on disaster preparedness in Japan. Her award supports her doctoral research under the title “Modeling the Mekong: Climate Adaptation Imaginaries in Delta Regions,” which will include fieldwork in Vietnam, the Netherlands, Thailand, and Cambodia.

      “Lizzie’s research brings together three dimensions critical to global well-being and sustainability: adapting to the inevitability of changing ecosystems wrought by the climate crisis; questioning the equity, appropriateness, and relationality of adaptation planning models spanning the global North and the global South; and understanding how to develop durable and just climate futures,” says Christopher Zegras, professor of mobility and urban planning and department head for DUSP. “Her work will be an important contribution toward the long-term health of our planet and of communities working to justly adapt to climate change.”

      Previously, Yarina was awarded a U.S. Scholarship Fulbright to New Zealand to research spatial mapping and policy implications of Pacific Islander migration to New Zealand.

      “My dissertation project looks at climate adaptation planning in delta regions,” she says. “My focus is on Vietnam’s Mekong River Delta, but I’m also looking at how models that are used in delta adaptation planning move between different deltas, including the Netherlands Rhine Delta and the Mississippi Delta.”

      Working on her masters at MIT, Yarina had a teaching fellowship in Singapore, where she conducted research on climate adaptation plans in four major cities in Southeast Asia.

      “Through that process I learned about the role of Dutch experts and Dutch models in shaping how climate adaptation planning was taking place in Southeast Asia,” she says. “This project expands on that work from looking at a single city to examining a regional plan at the scale of a delta.”

      Yarina holds a joint masters in architecture and masters of city planning from MIT, and a BS in architecture from the University of Michigan. More

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      in Energy

      Seeing the plasma edge of fusion experiments in new ways with artificial intelligence

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      To make fusion energy a viable resource for the world’s energy grid, researchers need to understand the turbulent motion of plasmas: a mix of ions and electrons swirling around in reactor vessels. The plasma particles, following magnetic field lines in toroidal chambers known as tokamaks, must be confined long enough for fusion devices to produce significant gains in net energy, a challenge when the hot edge of the plasma (over 1 million degrees Celsius) is just centimeters away from the much cooler solid walls of the vessel.

      Abhilash Mathews, a PhD candidate in the Department of Nuclear Science and Engineering working at MIT’s Plasma Science and Fusion Center (PSFC), believes this plasma edge to be a particularly rich source of unanswered questions. A turbulent boundary, it is central to understanding plasma confinement, fueling, and the potentially damaging heat fluxes that can strike material surfaces — factors that impact fusion reactor designs.

      To better understand edge conditions, scientists focus on modeling turbulence at this boundary using numerical simulations that will help predict the plasma’s behavior. However, “first principles” simulations of this region are among the most challenging and time-consuming computations in fusion research. Progress could be accelerated if researchers could develop “reduced” computer models that run much faster, but with quantified levels of accuracy.

      For decades, tokamak physicists have regularly used a reduced “two-fluid theory” rather than higher-fidelity models to simulate boundary plasmas in experiment, despite uncertainty about accuracy. In a pair of recent publications, Mathews begins directly testing the accuracy of this reduced plasma turbulence model in a new way: he combines physics with machine learning.

      “A successful theory is supposed to predict what you’re going to observe,” explains Mathews, “for example, the temperature, the density, the electric potential, the flows. And it’s the relationships between these variables that fundamentally define a turbulence theory. What our work essentially examines is the dynamic relationship between two of these variables: the turbulent electric field and the electron pressure.”

      In the first paper, published in Physical Review E, Mathews employs a novel deep-learning technique that uses artificial neural networks to build representations of the equations governing the reduced fluid theory. With this framework, he demonstrates a way to compute the turbulent electric field from an electron pressure fluctuation in the plasma consistent with the reduced fluid theory. Models commonly used to relate the electric field to pressure break down when applied to turbulent plasmas, but this one is robust even to noisy pressure measurements.

      In the second paper, published in Physics of Plasmas, Mathews further investigates this connection, contrasting it against higher-fidelity turbulence simulations. This first-of-its-kind comparison of turbulence across models has previously been difficult — if not impossible — to evaluate precisely. Mathews finds that in plasmas relevant to existing fusion devices, the reduced fluid model’s predicted turbulent fields are consistent with high-fidelity calculations. In this sense, the reduced turbulence theory works. But to fully validate it, “one should check every connection between every variable,” says Mathews.

      Mathews’ advisor, Principal Research Scientist Jerry Hughes, notes that plasma turbulence is notoriously difficult to simulate, more so than the familiar turbulence seen in air and water. “This work shows that, under the right set of conditions, physics-informed machine-learning techniques can paint a very full picture of the rapidly fluctuating edge plasma, beginning from a limited set of observations. I’m excited to see how we can apply this to new experiments, in which we essentially never observe every quantity we want.”

      These physics-informed deep-learning methods pave new ways in testing old theories and expanding what can be observed from new experiments. David Hatch, a research scientist at the Institute for Fusion Studies at the University of Texas at Austin, believes these applications are the start of a promising new technique.

      “Abhi’s work is a major achievement with the potential for broad application,” he says. “For example, given limited diagnostic measurements of a specific plasma quantity, physics-informed machine learning could infer additional plasma quantities in a nearby domain, thereby augmenting the information provided by a given diagnostic. The technique also opens new strategies for model validation.”

      Mathews sees exciting research ahead.

      “Translating these techniques into fusion experiments for real edge plasmas is one goal we have in sight, and work is currently underway,” he says. “But this is just the beginning.”

      Mathews was supported in this work by the Manson Benedict Fellowship, Natural Sciences and Engineering Research Council of Canada, and U.S. Department of Energy Office of Science under the Fusion Energy Sciences program.​ More