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      in Security

      Food for thought, thought for food

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      According to the Food and Agriculture Organization of the United Nations, approximately 3.1 billion people worldwide were unable to afford a healthy diet in 2020. Meanwhile, in 2021 close to 2.3 billion people were moderately or severely food insecure. Given the strong link between malnutrition and income disparity, the numbers paint a grim picture representing one of the grand challenges of our time.

      “I’m probably an idealist,” says MIT Research Scientist Christopher Mejía Argueta, “but I really believe that if we change our diets and think about ways to help others, we can make a difference — that’s my motivation.”

      Mejía Argueta is the founder and director of the MIT Food and Retail Operations Lab (FaROL). He has more than a decade of experience in supply chain management, optimization, and effective data-driven decision-making on pressing issues like the evolution of end consumers for retail and e-tail supply chains, food waste, and equitable access to nutrition.  

      Supply chain network designs typically focus on minimizing costs without considering the implications (e.g., cost) of changes in consumer behavior. Mejía Argueta and his colleagues at the FaROL, however, are working to understand and design optimal supply chains to create high-performance operations based on consumer choice. “Understanding the significant factors of consumer choice and analyzing their evolution over time becomes critical to designing forward-looking retail operations with data-driven and customer-centric supply chains, inventory management, and distribution systems,” explains Mejía Argueta. 

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      One of his recent projects examined the challenges of small retailers worldwide. These mom-and-pop outlets, or nanostores, account for 50 percent of the global market share and are the primary source of consumer packaged goods for people in urban areas. Worldwide there are nearly 50 million nanostores, each serving between 100-200 households in a community. In India alone, there are 14 million nanostores known as kiranas. And while these retailers are more prevalent in emerging markets, they play an important role in developed markets, particularly in under-resourced communities, and are frequently located in “food deserts,” where they are the only source of essential goods for the community.  

      These small retailers thrive thanks, partly, to their ability to offer the right combination of affordability and convenience while fostering trust with local customers, who often lack access to a supermarket or a grocery store. They often exist in fragmented, densely populated areas where infrastructure and public transportation services are poor and consumers have limited purchasing power. But nanostore shopkeepers and owners are intimately familiar with their customers and their consumption patterns, which means they can connect those consumption patterns or information to the larger supply chain. According to Mejía Argueta, when it comes to the future of retail, nanostores will be the cornerstones of growth in emerging economies. 

      But it’s a complicated scenario. Mom-and-pop shops don’t have the capacity to offer a broad range of products to their customers, and often, they lack access to nutritious food options. Logistically speaking, it is expensive to supply them, and the cost-to-serve (i.e., the logistics cost) is between 10 to 30 percent more expensive than other retailers. According to Mejía Argueta, this has a significant ripple effect, impacting education, productivity, and, eventually, the economic performance of an entire nation.  

      “The high fragmentation of nanostores causes substantial distribution inefficiencies, especially in congested megacities,” he says. “At my lab, we study how to make nanostores more efficient and effective by considering various commercial and logistics strategies while considering inherent technical challenges. We need to serve these small retailers better to help them survive and thrive, to provide a greater impact for underserved communities and the entire economic ecosystem.”

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      Mejía Argueta and his team recently collaborated with Tufts University and the City of Somerville, Massachusetts, to conduct research on food access models in underserved communities. The Somerville Project explored various interventions to supply fresh produce in food desert neighborhoods.

      “A lack of nutrition does not simply mean a lack of food,” Mejía Argueta says. “It can also be caused by an overabundance of unhealthy foods in a given market, which is particularly troublesome for U.S. cities where people in underserved communities don’t have access to healthy food options. We believe that one way to combat the problem of food deserts is to supply these areas with healthy food options affordably and create awareness programs.”  

      The collaborative project saw Mejía Argueta and his colleagues assessing the impact of several intervention schemes designed to empower the end consumer. For example, they implemented a low-cost grocery delivery model similar to Instacart as well as a ride sharing system to transport people from their homes to grocery stores and back. They also collaborated with a nonprofit organization, Partnership for a Healthier America, and began working with retailers to deliver “veggie boxes” in underserved communities. Models like these provide low-income people access to food while providing dignity of choice, Mejía Argueta explains.  

      When it comes to supply chain management research, sustainability and societal impact often fall by the wayside, but Mejía Argueta’s bottom-up approach shirks tradition. “We’re trying to build a community, employing a socially driven perspective because if you work with the community, you gain their trust. If you want to make something sustainable in the long term, people need to trust in these solutions and engage with the ecosystem as a whole.”  

      And to achieve real-world impact, collaboration is key. Mejía Argueta says that government has an important role to play, developing policy to connect the models he and his colleagues develop in academia to societal challenges. Meanwhile, he believes startups and entrepreneurs can function as bridge-builders to link the flows of information, the flows of goods and cash, and even knowledge and security in an ecosystem that suffers from fragmentation and siloed thinking among stakeholders.

      Finally, Mejía Argueta reflects on the role of corporations and his belief that the MIT Industrial Liaison Program is essential to getting his research to the frontline of business challenges. “The Industrial Liaison Program does a fantastic job of connecting our research to real-world scenarios,” he says. “It creates opportunities for us to have meaningful interactions with corporates for real-world impact. I believe strongly in the MIT motto ‘mens et manus,’ and ILP helps drive our research into practice.” More

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      in Energy

      Pursuing a practical approach to research

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      Koroush Shirvan, the John Clark Hardwick Career Development Professor in the Department of Nuclear Science and Engineering (NSE), knows that the nuclear industry has traditionally been wary of innovations until they are shown to have proven utility. As a result, he has relentlessly focused on practical applications in his research, work that has netted him the 2022 Reactor Technology Award from the American Nuclear Society. “The award has usually recognized practical contributions to the field of reactor design and has not often gone to academia,” Shirvan says.

      One of these “practical contributions” is in the field of accident-tolerant fuels, a program launched by the U.S. Nuclear Regulatory Commission in the wake of the 2011 Fukushima Daiichi incident. The goal within this program, says Shirvan, is to develop new forms of nuclear fuels that can tolerate heat. His team, with students from over 16 countries, is working on numerous possibilities that range in composition and method of production.

      Another aspect of Shirvan’s research focuses on how radiation impacts heat transfer mechanisms in the reactor. The team found fuel corrosion to be the driving force. “[The research] informs how nuclear fuels perform in the reactor, from a practical point of view,” Shirvan says.

      Optimizing nuclear reactor design

      A summer internship when Shirvan was an undergraduate at the University of Florida at Gainesville seeded his drive to focus on practical applications in his studies. A nearby nuclear utility was losing millions because of crud accumulating on fuel rods. Over time, the company was solving the problem by using more fuel, before it had extracted all the life from earlier batches.

      Placement of fuel rods in nuclear reactors is a complex problem with many factors — the life of the fuel, location of hot spots — affecting outcomes. Nuclear reactors change their configuration of fuel rods every 18-24 months to optimize close to 15-20 constraints, leading to roughly 200-800 assemblies. The mind-boggling nature of the problem means that plants have to rely on experienced engineers.

      During his internship, Shirvan optimized the program used to place fuel rods in the reactor. He found that certain rods in assemblies were more prone to the crud deposits, and reworked their configurations, optimizing for these rods’ performance instead of adding assemblies.

      In recent years, Shirvan has applied a branch of artificial intelligence — reinforcement learning — to the configuration problem and created a software program used by the largest U.S. nuclear utility. “This program gives even a layperson the ability to reconfigure the fuels and the reactor without having expert knowledge,” Shirvan says.

      From advanced math to counting jelly beans

      Shirvan’s own expertise in nuclear science and engineering developed quite organically. He grew up in Tehran, Iran, and when he was 14 the family moved to Gainesville, where Shirvan’s aunt and family live. He remembers an awkward couple of years at the new high school where he was grouped in with newly arrived international students, and placed in entry-level classes. “I went from doing advanced mathematics in Iran to counting jelly beans,” he laughs.

      Shirvan applied to the University of Florida for his undergraduate studies since it made economic sense; the school gave full scholarships to Floridian students who received a certain minimum SAT score. Shirvan qualified. His uncle, who was a professor in the nuclear engineering department then, encouraged Shirvan to take classes in the department. Under his uncle’s mentorship, the courses Shirvan took, and his internship, cemented his love of the interdisciplinary approach that the field demanded.

      Having always known that he wanted to teach — he remembers finishing his math tests early in Tehran so he could earn the reward of being class monitor — Shirvan knew graduate school was next. His uncle encouraged him to apply to MIT and to the University of Michigan, home to reputable programs in the field. Shirvan chose MIT because “only at MIT was there a program on nuclear design. There were faculty dedicated to designing new reactors, looking at multiple disciplines, and putting all of that together.” He went on to pursue his master’s and doctoral studies at NSE under the supervision of Professor Mujid Kazimi, focusing on compact pressurized and boiling water reactor designs. When Kazimi passed away suddenly in 2015, Shirvan was a research scientist, and switched to tenure track to guide the professor’s team.

      Another project that Shirvan took in 2015: leadership of MIT’s course on nuclear reactor technology for utility executives. Offered only by the Institute, the program is an introduction to nuclear engineering and safety for personnel who might not have much background in the area. “It’s a great course because you get to see what the real problems are in the energy sector … like grid stability,” Shirvan says.

      A multipronged approach to savings

      Another very real problem nuclear utilities face is cost. Contrary to what one hears on the news, one of the biggest stumbling blocks to building new nuclear facilities in the United States is cost, which today can be up to three times that of renewables, Shirvan says. While many approaches such as advanced manufacturing have been tried, Shirvan believes that the solution to decrease expenditures lies in designing more compact reactors.

      His team has developed an open-source advanced nuclear cost tool and has focused on two different designs: a small water reactor using compact steam technology and a horizontal gas reactor. Compactness also means making fuels more efficient, as Shirvan’s work does, and in improving the heat exchange device. It’s all back to the basics and bringing “commercial viable arguments in with your research,” Shirvan explains.

      Shirvan is excited about the future of the U.S. nuclear industry, and that the 2022 Inflation Reduction Act grants the same subsidies to nuclear as it does for renewables. In this new level playing field, advanced nuclear still has a long way to go in terms of affordability, he admits. “It’s time to push forward with cost-effective design,” Shirvan says, “I look forward to supporting this by continuing to guide these efforts with research from my team.” More

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      in Environment

      Machinery of the state

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      In Mai Hassan’s studies of Kenya, she documented the emergence of a sprawling administrative network officially billed as encouraging economic development, overseeing the population, and bolstering democracy. But Hassan’s field interviews and archival research revealed a more sinister purpose for the hundreds of administrative and security offices dotting the nation: “They were there to do the presidents’ bidding, which often involved coercing their own countrymen.”

      This research served as a catalyst for Hassan, who joined MIT as an associate professor of political science in July, to investigate what she calls the “politicized management of bureaucracy and the state.” She set out to “understand the motivations, capacities, and roles of people administering state programs and social functions,” she says. “I realized the state is not a faceless being, but instead comprised of bureaucrats carrying out functions on behalf of the state and the regime that runs it.”

      Today, Hassan’s portfolio encompasses not just the bureaucratic state but democratization efforts in Kenya and elsewhere in the East Africa region, including her native Sudan. Her research highlights the difficulties of democratization. “I’m finding that the conditions under which people come together for overthrowing an autocratic regime really matter, because those conditions may actually impede a nation from achieving democracy,” she says.

      A coordinated bureaucracy

      Hassan’s academic engagement with the state’s administrative machinery began during graduate school at Harvard University, where she earned her master’s and doctorate in government. While working with a community trash and sanitation program in some Kenyan Maasai communities, Hassan recalls “shepherding myself from office to office, meeting different bureaucrats to obtain the same approvals but for different jurisdictions.” The Kenyan state had recently set up hundreds of new local administrative units, motivated by what it claimed was the need for greater efficiency. But to Hassan’s eyes, “the administrative network was not well organized, seemed costly to maintain, and seemed to hinder — not bolster — development,” she says. What then, she wondered, was “the political logic behind such state restructuring?”

      Hassan began researching this bureaucratic transformation of Kenya, speaking with administrators in communities large and small who were charged with handling the business of the state. These studies yielded a wealth of findings for her dissertation, and for multiple journals.

      But upon finishing this tranche of research, Hassan realized that it was insufficient simply to study the structure of the state. “Understanding the role of new administrative structures for politics, development, and governance fundamentally requires that we understand who the government has put in charge of them,” she says. Among her insights:

      “The president’s office knows a lot of these administrators, and thinks about their strengths, limitations, and fit within a community,” says Hassan. Some administrators served the purposes of the central government by setting up water irrigation projects or building a new school. But in other villages, the state chose administrators who could act “much more coercively, ignoring development needs, throwing youth who supported the opposition into jail, and spending resources exclusively on policing.”

      Hassan’s work showed that in communities characterized by strong political opposition, “the local administration was always more coercive, regardless of an elected or autocratic president,” she says. Notably, the tenures of such officials proved shorter than those of their peers. “Once administrators get to know a community — going to church and the market with residents — it’s hard to coerce them,” explains Hassan.

      These short tenures come with costs, she notes: “Spending significant time in a station is useful for development, because you know exactly whom to hire if you want to build a school or get something done efficiently.” Politicizing these assignments undermines efforts at delivery of services and, more broadly, economic improvement nationwide. “Regimes that are more invested in retaining power must devote resources to establishing and maintaining control, resources that could otherwise be used for development and the welfare of citizens,” she says.

      Hassan wove together her research covering three presidents over a 50-year period, in the book, “Regime Threats and State Solutions: Bureaucratic Loyalty and Embeddedness in Kenya” (2020, Cambridge University Press), named a Foreign Affairs Best Book of 2020.

      Sudanese roots

      The role of the state in fulfilling the needs of its citizens has long fascinated Hassan. Her grandfather, who had served as Sudan’s ambassador to the USSR, talked to her about the advantages of a centralized government “that allocated resources to reduce inequality,” she says.

      Politics often dominated the conversation in gatherings of Hassan’s family and friends. Her parents immigrated to northern Virginia when she was very young, and many relatives joined them, part of a steady flow of Sudanese fleeing political turmoil and oppression.

      “A lot of people had expected more from the Sudanese state after independence and didn’t get it,” she says. “People had hopes for what the government could and should do.”

      Hassan’s Sudanese roots and ongoing connection to the Sudanese community have shaped her academic interests and goals. At the University of Virginia, she gravitated toward history and economics classes. But it was her time at the Ralph Bunche Summer institute that perhaps proved most pivotal in her journey. This five-week intensive program is offered by the American Political Science Association to introduce underrepresented undergraduate students to doctoral studies. “It was really compelling in this program to think rigorously about all the political ideas I’d heard as I was growing up, and find ways to challenge some assertions empirically,” she says.

      Regime change and civil society

      At Harvard, Hassan first set out to focus on Sudan for her doctoral program. “There wasn’t much scholarship on the country, and what there was lacked rigor,” she says. “That was something that needed to change.” But she decided to postpone this goal after realizing that she might be vulnerable as a student conducting field research there. She landed instead in Kenya, where she honed her interviewing and data collection skills.

      Today, empowered by her prior work, she has returned to Sudan. “I felt that the popular uprising in Sudan and ousting of the Islamist regime in 2019 should be documented and analyzed,” she says. “It was incredible that hundreds of thousands, if not millions, acted collectively to uproot a dictator, in the face of brutal violence from the state.”But “democracy is still uncertain there,” says Hassan. The broad coalition behind regime change “doesn’t know how to govern because different people and different sectors of society have different ideas about what democratic Sudan should look like,” she says. “Overthrowing an autocratic regime and having civil society come together to figure out what’s going to replace it require different things, and it’s unclear if a movement that accomplishes the first is well-suited to do the second.”

      Hassan believes that in order to create lasting democratization, “you need the hard work of building organizations, developing ways in which members learn to compromise among themselves, and make decisions and rules for how to move forward.”

      Hassan is enjoying the fall semester and teaching courses on autocracy and authoritarian regimes. She is excited as well about developing her work on African efforts at democratic mobilization in a political science department she describes as “policy-forward.”

      Over time, she hopes to connect with Institute scholars in the hard sciences to think about other challenges these nations are facing, such as climate change. “It’s really hot in Sudan, and it may be one of the first countries to become completely uninhabitable,” she says. “I’d like to explore strategies for growing crops differently or managing the exceedingly scarce resource of water, and figure out what kind of political discussions will be necessary to implement any changes. It is really critical to think about these problems in an interdisciplinary way.” More

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      in Energy

      On batteries, teaching, and world peace

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      Over his long career as an electrochemist and professor, Donald Sadoway has earned an impressive variety of honors, from being named one of Time magazine’s 100 most influential people in 2012 to appearing on “The Colbert Report,” where he talked about “renewable energy and world peace,” according to Comedy Central.

      What does he personally consider to be his top achievements?

      “That’s easy,” he says immediately. “For teaching, it’s 3.091,” the MIT course on solid-state chemistry he led for some 18 years. An MIT core requirement, 3.091 is also one of the largest classes at the Institute. In 2003 it was the largest, with 630 students. Sadoway, who retires this year after 45 years in the Department of Materials Science and Engineering, estimates that over the years he’s taught the course to some 10,000 undergraduates.

      A passion for teaching

      Along the way he turned the class into an MIT favorite, complete with music, art, and literature. “I brought in all that enrichment because I knew that 95 percent of the students in that room weren’t going to major in anything chemical and this might be the last class they’d take in the subject. But it’s a requirement. So they’re 18 years old, they’re very smart, and many of them are very bored. You have to find a hook [to reach them]. And I did.”

      In 1995, Sadoway was named a Margaret MacVicar Faculty Fellow, an honor that recognizes outstanding classroom teaching at the Institute. Among the communications in support of his nomination:

      “His contributions are enormous and the class is in rapt attention from beginning to end. His lectures are highly articulate yet animated and he has uncommon grace and style. I was awed by his ability to introduce playful and creative elements into a core lecture…”

      Bill Gates would agree. In the early 2000s Sadoway’s lectures were shared with the world through OpenCourseWare, the web-based publication of MIT course materials. Gates was so inspired by the lectures that he asked to meet with Sadoway to learn more about his research. (Sadoway initially ignored Gates’ email because he thought his account had been hacked by MIT pranksters.)

      Research breakthroughs

      Teaching is not Sadoway’s only passion. He’s also proud of his accomplishments in electrochemistry. The discipline that involves electron transfer reactions is key to everything from batteries to the primary extraction of metals like aluminum and magnesium. “It’s quite wide-ranging,” says the John F. Elliott Professor Emeritus of Materials Chemistry.

      Sadoway’s contributions include two battery breakthroughs. First came the liquid metal battery, which could enable the large-scale storage of renewable energy. “That represents a huge step forward in the transition to green energy,” said António Campinos, president of the European Patent Office, earlier this year when Sadoway won the 2022 European Inventor Award for the invention in the category for Non-European Patent Office Countries.

      On “The Colbert Report,” Sadoway alluded to that work when he told Stephen Colbert that electrochemistry is the key to world peace. Why? Because it could lead to a battery capable of storing energy from the sun when the sun doesn’t shine and otherwise make renewables an important part of the clean energy mix. And that in turn could “plummet the price of petroleum and depose dictators all over the world without one shot being fired,” he recently recalled.

      The liquid metal battery is the focus of Ambri, one of six companies based on Sadoway’s inventions. Bill Gates was the first funder of the company, which formed in 2010 and aims to install its first battery soon. That battery will store energy from a reported 500 megawatts of on-site renewable generation, the same output as a natural gas power plant.

      Then, in August of this year, Sadoway and colleagues published a paper in Nature about “one of the first new battery chemistries in 30 years,” Sadoway says. “I wanted to invent something that was better, much better,” than the expensive lithium-ion batteries used in, for example, today’s electric cars.

      That battery is the focus of Avanti, one of three Sadoway companies formed just last year. The other two are Pure Lithium, to commercialize his inventions related to that element, and Sadoway Labs. The latter, a nonprofit, is essentially “a space to try radical innovations. We’re gonna start working on wild ideas.”

      Another focus of Sadoway’s research: green steel. Steelmaking produces huge amounts of greenhouse gases. Enter Boston Metal, another Sadoway company. This one is developing a new approach to producing steel based on research begun some 25 years ago. Unlike the current technology for producing steel, the Boston Metal approach — molten oxide electrolysis — does not use the element at the root of steel’s problems: carbon. The principal byproduct of the new system? Oxygen.

      In 2012, Sadoway gave a TED talk to 2,000 people on the liquid metal battery. He believes that that talk, which has now been seen by almost 2.5 million people, led to the wider publicity of his work — and science overall — on “The Colbert Report” and elsewhere. “The moral here is that if you step out of your comfort zone, you might be surprised at what can happen,” he concludes.

      Colleagues’ reflections

      “I met Don in 2006 when I was working for the iron and steel industry in Europe on ways to reduce greenhouse gas emissions from the production of those materials,” says Antoine Allanore, professor of metallurgy, Department of Materials Science and Engineering. “He was the same Don Sadoway that you see in recordings of his lectures: very elegant, very charismatic, and passionate about the technical solutions and underlying science of the process we were all investigating; electrolysis. A few years later, when I decided to pursue an academic career, I contacted Don and became a postdoctoral associate in his lab. That ultimately led to my becoming an MIT professor. People don’t believe me, but before I came to MIT the only thing I knew about the Institute was that Noam Chomsky was there … and Don Sadoway. And I felt, that’s a great place to be. And I stayed because I saw the exceptional things that can be accomplished at MIT and Don is the perfect example of that.”

      “I had the joy of meeting Don when I first arrived on the MIT campus in 1994,” recalls Felice Frankel, research scientist in the MIT departments of Chemical Engineering and Mechanical Engineering. “I didn’t have to talk him into the idea that researchers needed to take their images and graphics more seriously.  He got it — that it wasn’t just about pretty pictures. He was an important part of our five-year National Science Foundation project — Picturing to Learn — to bring that concept into the classroom. How lucky that was for me!”

      “Don has been a friend and mentor since we met in 1995 when I was an MIT senior,” says Luis Ortiz, co-founder and chief executive officer, Avanti Battery Co. “One story that is emblematic of Don’s insistence on excellence is from when he and I met with Bill Gates about the challenges in addressing climate change and how batteries could be the linchpin in solving them. I suggested that we create our presentation in PowerPoint [Microsoft software]. Don balked. He insisted that we present using Keynote on his MacBook Air, because ‘it looks so much better.’ I was incredulous that he wanted to walk into that venue exclusively using Apple products. Of course, he won the argument, but not without my admonition that there had better not be even a blip of an issue. In the meeting room, Microsoft’s former chief technology officer asked Don if he needed anything to hook up to the screen, ‘we have all those dongles.’ Don declined, but gave me that knowing look and whispered, ‘You see, they know, too.’ I ate my crow and we had a great long conversation without any issues.”

      “I remember when I first started working with Don on the liquid metal battery project at MIT, after I had chosen it as the topic for my master’s of engineering thesis,” adds David Bradwell, co-founder and chief technology officer, Ambri. “I was a wide-eyed graduate student, sitting in his office, amongst his art deco decorations, unique furniture, and historical and stylistic infographics, and from our first meeting, I could see Don’s passion for coming up with new and creative, yet practical scientific ideas, and for working on hard problems, in service of society. Don’s approaches always appear to be unconventional — wanting to stand out in a crowd, take the path less trodden, both based on his ideas, and his sense of style. It’s been an amazing journey working with him over the past decade-and-a-half, and I remain excited to see what other new, unconventional ideas, he can bring to this world.” 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

      Studying floods to better predict their dangers

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      “My job is basically flooding Cambridge,” says Katerina “Katya” Boukin, a graduate student in civil and environmental engineering at MIT and the MIT Concrete Sustainability Hub’s resident expert on flood simulations. 

      You can often find her fine-tuning high-resolution flood risk models for the City of Cambridge, Massachusetts, or talking about hurricanes with fellow researcher Ipek Bensu Manav.

      Flooding represents one of the world’s gravest natural hazards. Extreme climate events inducing flooding, like severe storms, winter storms, and tropical cyclones, caused an estimated $128.1 billion of damages in 2021 alone. 

      Climate simulation models suggest that severe storms will become more frequent in the coming years, necessitating a better understanding of which parts of cities are most vulnerable — an understanding that can be improved through modeling.

      A problem with current flood models is that they struggle to account for an oft-misunderstood type of flooding known as pluvial flooding. 

      “You might think of flooding as the overflowing of a body of water, like a river. This is fluvial flooding. This can be somewhat predictable, as you can think of proximity to water as a risk factor,” Boukin explains.

      However, the “flash flooding” that causes many deaths each year can happen even in places nowhere near a body of water. This is an example of pluvial flooding, which is affected by terrain, urban infrastructure, and the dynamic nature of storm loads.

      “If we don’t know how a flood is propagating, we don’t know the risk it poses to the urban environment. And if we don’t understand the risk, we can’t really discuss mitigation strategies,” says Boukin, “That’s why I pursue improving flood propagation models.”

      Boukin is leading development of a new flood prediction method that seeks to address these shortcomings. By better representing the complex morphology of cities, Boukin’s approach may provide a clearer forecast of future urban flooding.

      Katya Boukin developed this model of the City of Cambridge, Massachusetts. The base model was provided through a collaboration between MIT, the City of Cambridge, and Dewberry Engineering.

      Image: Katya Boukin

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      “In contrast to the more typical traditional catchment model, our method has rainwater spread around the urban environment based on the city’s topography, below-the-surface features like sewer pipes, and the characteristics of local soils,” notes Boukin.

      “We can simulate the flooding of regions with local rain forecasts. Our results can show how flooding propagates by the foot and by the second,” she adds.

      While Boukin’s current focus is flood simulation, her unconventional academic career has taken her research in many directions, like examining structural bottlenecks in dense urban rail systems and forecasting ground displacement due to tunneling. 

      “I’ve always been interested in the messy side of problem-solving. I think that difficult problems present a real chance to gain a deeper understanding,” says Boukin.

      Boukin credits her upbringing for giving her this perspective. A native of Israel, Boukin says that civil engineering is the family business. “My parents are civil engineers, my mom’s parents are, too, her grandfather was a professor in civil engineering, and so on. Civil engineering is my bloodline.”

      However, the decision to follow the family tradition did not come so easily. “After I took the Israeli equivalent of the SAT, I was at a decision point: Should I go to engineering school or medical school?” she recalls.

      “I decided to go on a backpacking trip to help make up my mind. It’s sort of an Israeli rite to explore internationally, so I spent six months in South America. I think backpacking is something everyone should do.”

      After this soul searching, Boukin landed on engineering school, where she fell in love with structural engineering. “It was the option that felt most familiar and interesting. I grew up playing with AutoCAD on the family computer, and now I use AutoCAD professionally!” she notes.

      “For my master’s degree, I was looking to study in a department that would help me integrate knowledge from fields like climatology and civil engineering. I found the MIT Department of Civil and Environmental Engineering to be an excellent fit,” she says.

      “I am lucky that MIT has so many people that work together as well as they do. I ended up at the Concrete Sustainability Hub, where I’m working on projects which are the perfect fit between what I wanted to do and what the department wanted to do.” 

      Boukin’s move to Cambridge has given her a new perspective on her family and childhood. 

      “My parents brought me to Israel when I was just 1 year old. In moving here as a second-time immigrant, I have a new perspective on what my parents went through during the move to Israel. I moved when I was 27 years old, the same age as they were. They didn’t have a support network and worked any job they could find,” she explains.

      “I am incredibly grateful to them for the morals they instilled in my sister, who recently graduated medical school, and I. I know I can call my parents if I ever need something, and they will do whatever they can to help.”

      Boukin hopes to honor her parents’ efforts through her research.

      “Not only do I want to help stakeholders understand flood risks, I want to make awareness of flooding more accessible. Each community needs different things to be resilient, and different cultures have different ways of delivering and receiving information,” she says.

      “Everyone should understand that they, in addition to the buildings and infrastructure around them, are part of a complex ecosystem. Any change to a city can affect the rest of it. If designers and residents are aware of this when considering flood mitigation strategies, we can better design cities and understand the consequences of damage.” 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).

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      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

      A lasting — and valuable — legacy

      by

      Betar Gallant, MIT associate professor and Class of 1922 Career Development Chair in Mechanical Engineering, grew up in a curious, independently minded family. Her mother had multiple jobs over the years, including in urban planning and in the geospatial field. Her father, although formally trained in English, read textbooks of all kinds from cover to cover, taught himself numerous technical fields including engineering, and worked successfully in them. When Gallant was very young, she and her father did science experiments in the basement.

      It wasn’t until she was in her teenage years, though, that she says she got drawn into science. Her father, who had fallen ill five years before, died when Gallant was 16, and while grieving, “when I was missing him the most,” she started to look at what had captivated her father.

      “I started to take a deeper interest in the things he had spent his life working on as a way to feel closer to him in his absence,” Gallant says. “I spent a few long months one summer looking through some of the things he had worked on, and found myself reading physics textbooks. That was enough, and I was hooked.”

      The love for independently finding and understanding solutions, that she had apparently inherited from her parents, eventually took her to the professional love of her life: electrochemistry.

      As an undergraduate at MIT, Gallant did an Undergraduate Research Opportunities Program project with Professor Yang Shao-Horn’s research group that went from her sophomore year through her senior thesis. This was Gallant’s first official exposure to electrochemistry.

      “When I met Yang, she showed me very quickly how challenging and enriching electrochemistry can be, and there was real conviction and excitement in how she and her group members talked about research,” Gallant says. “It was totally eye-opening, and I’m fortunate that she was a (relatively rare) electrochemist in a mechanical engineering department, or else I likely would not have been able to go down that road.”

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      Gallant earned three degrees at MIT (’08, SM ’10, and PhD ’13). Before joining the MIT faculty in 2016, she was a Kavli Nanoscience Institute Prize Postdoctoral Fellow at Caltech in the Division of Chemistry and Chemical Engineering.

      Her passion for electrochemistry is enormous. “Electrons are just dazzling — they power so much of our everyday world, and are the key to a renewable future,” she says, explaining that despite electrons’ amazing potential, isolated electrons cannot be stored and produced on demand, because “nature doesn’t allow excessive amounts of charge imbalances to accumulate.”

      Electrons can, however, be stored on molecules, in bonds and in metal ions or nonmetal centers that are able to lose and gain electrons — as long as positive charge transfers occur to accommodate the electrons.

      “Here’s where chemistry rears its head,” Gallant says. “What types of molecules or materials can behave in this way? How do we store as much charge as possible while making the weight and volume as low as possible?”

      Gallant points out that early battery developers using lithium and ions built a technology that “has arguably shaped our modern world more than any other.

      “If you look at some early papers, the concepts of how a lithium-ion battery or a lithium metal anode worked were sketched out by hand — they had been deduced to be true, before the field even had the tools to prove all the mechanisms were actually occurring — yet even now, those ideas are still turning out to be right!”

      Gallant says, “that’s because if you truly understand the basic principles of electrochemistry, you can start to intuit how systems will behave. Once you can do that, you can really begin to engineer better materials and devices.”

      Truly her father’s daughter, Gallant’s emphasis is on independently finding solutions.

      “Ultimately, it’s a race to have the best mental models,” she says. “A great lab and lots of funding and personnel to run it are very nice, but the most valuable tools in the toolbox are solid mental models and a way of thinking about electrochemistry, which is actually very personalized depending on the researcher.”

      She says one project with immediate impact that’s coming out of her Gallant Energy and Carbon Conversion Lab relates to primary (non-rechargeable) battery work that she and her team are working to commercialize. It involves injecting new electrochemically active electrolytes into leading high-energy batteries as they’re being assembled. Replacing a conventional electrolyte with the new chemistry decreases the normally inactive weight of the battery and boosts the energy substantially, Gallant says. One important application of such batteries would be for medical devices such as pacemakers.

      “If you can extend lifetime, you’re talking about longer times between invasive replacement surgeries, which really affects patient quality of life,” she says.

      Gallant’s team is also leading efforts to enable higher-energy rechargeable lithium-ion batteries for electric vehicles. Key to a step-change in energy, and therefore driving range, is to use a lithium metal anode in place of graphite. Lithium metal is highly reactive, however, with all battery electrolytes, and its interface needs to be stabilized in ways that still elude researchers. Gallant’s team is developing design guidelines for such interfaces, and for next-generation electrolytes to form and sustain these interfaces. Gallant says that applying the technology to that purpose and commercializing it would be “a bit longer-term, but I believe this change to lithium anodes will happen, and it’s just a matter of when.”

      About six years ago, when Gallant founded her lab, she and her team started introducing carbon dioxide into batteries as a way to experiment with electrochemical conversion of the greenhouse gas. She says they realized that batteries do not present the best practical technology to mitigate CO2, but their experimentation did open up new paths to carbon capture and conversion. “That work allowed us to think creatively, and we started to realize that there is tremendous potential to manipulate CO2 reactions by carefully designing the electrochemical environment.” That led her team to the idea of conducting electrochemical transformations on CO2 from a captured state bound to a capture sorbent, replacing the energy-intense regeneration step of today’s capture processes and streamlining the process.  

      “Now we’re seeing other researchers working on that, too, and taking this idea in exciting directions — it’s a very challenging and very rich topic,” she says.

      Gallant has won awards including an MIT Bose Fellowship, the Army Research Office Young Investigator Award, the Scialog Fellowship in Energy Storage and in Negative Emissions Science, a CAREER award from the National Science Foundation, the Ruth and Joel Spira Award for Distinguished Teaching at MIT, the Electrochemical Society (ECS) Battery Division Early Career award, and an ECS-Toyota Young Investigator Award.

      These days, Gallant does some of her best thinking while brainstorming with her research group members and with her husband, who is also an academic. She says being a professor at MIT means she has “a queue of things to think about,” but she sometimes gets awarded with a revelation.

      “My brain gets overloaded because I can’t think through everything instantaneously; ideas have to get in line! So there’s a lot going on in the background at all times,” she say. “I don’t know how it works, but sometimes I’ll be going for a walk or doing something else, and an idea breaks through. Those are the fun ones.” More