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      in Energy

      MIT students contribute to success of historic fusion experiment

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      For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition in a laboratory, a grand challenge of the 21st century. The High-Energy-Density Physics (HEDP) group at MIT’s Plasma Science and Fusion Center has focused on an approach called inertial confinement fusion (ICF), which uses lasers to implode a pellet of fuel in a quest for ignition. This group, including nine former and current MIT students, was crucial to an historic ICF ignition experiment performed in 2021; the results were published on the anniversary of that success.

      On Aug. 8, 2021, researchers at the National Ignition Facility (NIF), Lawrence Livermore National Laboratory (LLNL), used 192 laser beams to illuminate the inside of a tiny gold cylinder encapsulating a spherical capsule filled with deuterium-tritium fuel in their quest to produce significant fusion energy. Although researchers had followed this process many times before, using different parameters, this time the ensuing implosion produced an historic fusion yield of 1.37 megaJoules, as measured by a suite of neutron diagnostics. These included the MIT-developed and analyzed Magnetic Recoil Spectrometer (MRS). This result was published in Physical Review Letters on Aug. 8, the one-year anniversary of the ground-breaking development, unequivocally indicating that the first controlled fusion experiment reached ignition.

      Governed by the Lawson criterion, a plasma ignites when the internal fusion heating power is high enough to overcome the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop that very rapidly increases the plasma temperature. In the case of ICF, ignition is a state where the fusion plasma can initiate a “fuel burn propagation” into the surrounding dense and cold fuel, enabling the possibility of high fusion-energy gain.

      “This historic result certainly demonstrates that the ignition threshold is a real concept, with well-predicted theoretical calculations, and that a fusion plasma can be ignited in a laboratory” says HEDP Division Head Johan Frenje.

      The HEDP division has contributed to the success of the ignition program at the NIF for more than a decade by providing and using a dozen diagnostics, implemented by MIT PhD students and staff, which have been critical for assessing the performance of an implosion. The hundreds of co-authors on the paper attest to the collaborative effort that went into this milestone. MIT’s contributors included the only student co-authors.

      “The students are responsible for implementing and using a diagnostic to obtain data important to the ICF program at the NIF, says Frenje. “Being responsible for running a diagnostic at the NIF has allowed them to actively participate in the scientific dialog and thus get directly exposed to cutting-edge science.”

      Students involved from the MIT Department of Physics were Neel Kabadi, Graeme Sutcliffe, Tim Johnson, Jacob Pearcy, and Ben Reichelt; students from the Department of Nuclear Science and Engineering included Brandon Lahmann, Patrick Adrian, and Justin Kunimune.

      In addition, former student Alex Zylstra PhD ’15, now a physicist at LLNL, was the experimental lead of this record implosion experiment. More

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      in Security

      Promoting systemic change in the Middle East, the “MIT way”

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      The Middle East is a region that is facing complicated challenges. MIT programs have been committed to building scalable methodologies through which students and the broader MIT community can learn and make an impact. These processes ensure programs work alongside others across cultures to support change aligned with their needs. Through MIT International Science and Technology Initiatives (MISTI), faculty and staff at the Institute continue to build opportunities to connect with and support the region.

      In this spirit, MISTI launched the Leaders Journey Workshop in 2021. This program partnered MIT students with Palestinian and Israeli alumni from three associate organizations: Middle East Entrepreneurs for Tomorrow (MEET), Our Generation Speaks (OGS), and Tech2Peace. Teams met monthly to engage with speakers and work with one another to explore the best ways to leverage science, technology, and entrepreneurship across borders.

      Building on the success of this workshop, the program piloted a for-credit course: SP.258 (MISTI: Middle East Cross-Border Development and Leadership) in fall 2021. The course involved engaging with subject matter experts through five mini-consulting projects in collaboration with regional stakeholders. Topics included climate, health care, and economic development. The course was co-instructed by associate director of the MIT Regional Entrepreneurship Acceleration Program (REAP) Sinan AbuShanab, managing director of MISTI programs in the Middle East David Dolev, and Kathleen Schwind ’19, with MIT CIS/ MISTI Research Affiliate Steven Koltai as lead mentor. The course also drew support from alumni mentors and regional industry partners.

      The course was developed during the height of the pandemic and thus successfully leveraged the intense culture of online engagement prevalent at the time by layering in-person coursework with strategic digital group engagement. Pedagogically, the structure was inspired by multiple MIT methodologies: MISTI preparation and training courses, Sloan Action Learning, REAP/REAL multi-party stakeholder model, the Media Lab Learning Initiative, and the multicultural framework of associate organizations.

      “We worked to develop a series of aims and a methodology that would enrich MIT students and their peers in the region and support the important efforts of Israelis and Palestinians to make systemic change,” said Dolev.

      During the on-campus sessions, MIT students explored the region’s political and historical complexities and the meaning of being a global leader and entrepreneur. Guest presenters included: Boston College Associate Professor Peter Krause (MIT Security Studies Program alumnus), Gilad Rosenzweig (MITdesignX), Ari Jacobovits (MIT-Africa), and Mollie Laffin-Rose Agbiboa (MIT-REAP). Group projects focused on topics that fell under three key regional verticals: water, health care, and economic development. The teams were given a technical or business challenge they were tasked with solving. These challenges were sourced directly from for-profit and nonprofit organizations in the region.

      “This was a unique opportunity for me to learn so much about the area I live in, work on a project together with people from the ‘other side,’ MIT students, and incredible mentors,” shared a participant from the region. “Furthermore, getting a glimpse of the world of MIT was a great experience for me.”

      For their final presentations, teams pitched their solutions, including their methodology for researching/addressing the problem, a description of solutions to be applied, what is needed to execute the idea itself, and potential challenges encountered. Teams received feedback and continued to deepen their experience in cross-cultural teamwork.

      “As an education manager, I needed guidance with these digital tools and how to approach them,” says an EcoPeace representative. “The MIT program provided me with clear deliverables I can now implement in my team’s work.”

      “This course has broadened my knowledge of conflicts, relationships, and how geography plays an important role in the region,” says an MIT student participant. “Moving forward, I feel more confident working with business and organizations to develop solutions for problems in real time, using the skills I have to supplement the project work.”

      Layers of engagement with mentors, facilitators, and whole-team leadership ensured that participants gained project management experience, learning objectives were met, and professional development opportunities were available. Each team was assigned an MIT-MEET alumni mentor with whom they met throughout the course. Mentors coached the teams on methods for managing a client project and how to collaborate for successful completion. Joint sessions with MIT guest speakers deepened participants’ regional understanding of water, health care, economic development, and their importance in the region. Speakers included: Mohamed Aburawi, Phil Budden (MIT-REAP) Steven Koltai, Shari Loessberg, Dina Sherif (MIT Legatum Center, Greg Sixt (J-WAFS), and Shriya Srinivasan.

      “The program is unlike any other I’ve come across,” says one of the alumni mentors. “The chance for MIT students to work directly with peers from the region, to propose and create technical solutions to real problems on the ground, and partner with local organizations is an incredibly meaningful opportunity. I wish I had been able to participate in something like this when I was at MIT.”

      Each team also assigned a fellow group member as a facilitator, who served as the main point of contact for the team and oversaw project management: organizing workstreams, ensuring deadlines were met, and mediating any group disagreements. This model led to successful project outcomes and innovative suggestions.

      “The superb work of the MISTI group gave us a critical eye and made significant headway on a product that can hopefully be a game changer to over 150 Israeli and Palestinian organizations,” says a representative from Alliance for Middle East Peace (ALLMEP).

      Leadership team meetings included MIT staff and Israeli and Palestinian leadership of the partner organizations for discussing process, content, recent geopolitical developments, and how to adapt the class to the ongoing changing situation.

      “The topic of Palestine/Israel is contentious: globally, in the region, and also, at times, on the MIT campus,” says Dolev. “I myself have questioned how we can make a systemic impact with our partners from the region. How can we be side-by-side on that journey for the betterment of all? I have now seen first-hand how this multilayered model can work.”

      MIT International Science and Technology Initiatives (MISTI) is MIT’s hub for global experiences. MISTI’s unparalleled internship, research, teaching, and study abroad programs offer students unique experiences that bring MIT’s one-of-a-kind education model to life in countries around the world. MISTI programs are carefully designed to complement on-campus course work and research, and rigorous, country-specific preparation enables students to forge cultural connections and play a role in addressing important global challenges while abroad. Students come away from their experiences with invaluable perspectives that inform their education, career, and worldview. MISTI embodies MIT’s commitment to global engagement and prepares students to thrive in an increasingly interconnected world. More

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      in Energy

      Building better batteries, faster

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

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

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

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

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

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

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

      Leveraging machine learning to research battery materials

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

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

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

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

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

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

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

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

      Helping students navigate graduate school

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

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

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

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

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

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      in Environment

      From bridges to DNA: civil engineering across disciplines

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      How is DNA like a bridge? This question is not a riddle or logic game, it is a concern of Johannes Kalliauer’s doctoral thesis.

      As a student at TU Wien in Austria, Kalliauer was faced with a monumental task: combining approaches from civil engineering and theoretical physics to better understand the forces that act on DNA.

      Kalliauer, now a postdoc at the MIT Concrete Sustainability Hub, says he modeled DNA as though it were a beam, using molecular dynamics principles to understand its structural properties.

      “The mechanics of very small objects, like DNA helices, and large ones, like bridges, are quite similar. Each may be understood in terms of Newtonian mechanics. Forces and moments act on each system, subjecting each to deformations like twisting, stretching, and warping,” says Kalliauer.

      As a 2020 article from TU Wien noted, Kalliauer observed a counterintuitive behavior when examining DNA at an atomic level. Unlike a typical spring which becomes less coiled as it is stretched, DNA was observed to become more wound as its length was increased. 

      In situations like these where conventional logic appears to break down, Kalliauer relies on the intuition he has gained as an engineer.

      “To understand this strange behavior in DNA, I turned to a fundamental approach: I examined what was the same about DNA and macroscopic structures and what was different. Civil engineers use methods and calculations which have been developed over centuries and which are very similar to the ones I employed for my thesis,” Kalliauer explains. 

      As Kalliauer continues, “Structural engineering is an incredibly versatile discipline. If you understand it, you can understand atomistic objects like DNA strands and very large ones like galaxies. As a researcher, I rely on it to help me bring new viewpoints to fields like biology. Other civil engineers can and should do the same.”

      Kalliauer, who grew up in a small town in Austria, has spent his life applying unconventional approaches like this across disciplines. “I grew up in a math family. While none of us were engineers, my parents instilled an appreciation for the discipline in me and my two older sisters.”

      After middle school, Kalliauer attended a technical school for civil engineering, where he discovered a fascination for mechanics. He also worked on a construction site to gain practical experience and see engineering applied in a real-world context.

      Kalliauer studied out of interest intensely, working upwards of 100 hours per week to better understand coursework in university. “I asked teachers and professors many questions, often challenging their ideas. Above everything else, I needed to understand things for myself. Doing well on exams was a secondary concern.”

      In university, he studied topics ranging from car crash testing to concrete hinges to biology. As a new member of the CSHub, he is studying how floods may be modeled with the statistical physics-based model provided by lattice density functional theory.

      In doing this, he builds on the work of past and present CSHub researchers like Elli Vartziotis and Katerina Boukin. 

      “It’s important to me that this research has a real impact in the world. I hope my approach to engineering can help researchers and stakeholders understand how floods propagate in urban contexts, so that we may make cities more resilient,” he says. More

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      in Energy

      Pursuing progress at the nanoscale

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      Last fall, a team of five senior undergraduate nuclear engineering students met once a week for dinners where they took turns cooking and debated how to tackle a particularly daunting challenge set forth in their program’s capstone course, 22.033 (Nuclear Systems Design Project).

      In past semesters, students had free reign to identify any real-world problem that interested them to solve through team-driven prototyping and design. This past fall worked a little differently. The team continued the trend of tackling daunting problems, but instead got an assignment to explore a particular design challenge on MIT’s campus. Rising to the challenge, the team spent the semester seeking a feasible way to introduce a highly coveted technology at MIT.

      Housed inside a big blue dome is the MIT Nuclear Reactor Laboratory (NRL). The reactor is used to conduct a wide range of science experiments, but in recent years, there have been multiple attempts to implement an instrument at the reactor that could probe the structure of materials, molecules, and devices. With this technology, researchers could model the structure of a wide range of materials and complex liquids made of polymers or containing nanoscale inhomogeneities that differ from the larger mass. On campus, researchers for the first time could conduct experiments to better understand the properties and functions of anything placed in front of a neutron beam emanating from the reactor core.

      The impact of this would be immense. If the reactor could be adapted to conduct this advanced technique, known as small-angle neutron scattering (SANS), it would open up a whole new world of research at MIT.

      “It’s essentially using the nuclear reactor as an incredibly high-performance camera that researchers from all over MIT would be very interested in using, including nuclear science and engineering, chemical engineering, biological engineering, and materials science, who currently use this tool at other institutions,” says Zachary Hartwig, Nuclear Systems Design Project professor and the MIT Robert N. Noyce Career Development Professor.

      SANS instruments have been installed at fewer than 20 facilities worldwide, and MIT researchers have previously considered implementing the capability at the reactor to help MIT expand community-wide access to SANS. Last fall, this mission went from long-time campus dream to potential reality as it became the design challenge that Hartwig’s students confronted. Despite having no experience with SANS, the team embraced the challenge, taking the first steps to figure out how to bring this technology to campus.

      “I really loved the idea that what we were doing could have a very real impact,” says Zoe Fisher, Nuclear Systems Design Project team member and now graduate nuclear engineering student.

      Each fall, Hartwig uses the course to introduce students to real-world challenges with strict constraints on solutions, and last fall’s project came with plenty of thorny design questions for students to tackle. First was the size limitation posed by the space available at MIT’s reactor. In SANS facilities around the world, the average length of the instrument is 30 meters, but at NRL, the space available is approximately 7.5 meters. Second, these instruments can cost up to $30 million, which is far outside NRL’s proposed budget of $3 million. That meant not only did students need to design an instrument that would work in a smaller space, but also one that could be built for a tenth of the typical cost.

      “The challenge was not just implementing one of these instruments,” Hartwig says. “It was whether the students could significantly innovate beyond the ‘traditional’ approach to doing SANS to meet the daunting constraints that we have at the MIT Reactor.”

      Because NRL actually wants to pursue this project, the students had to get creative, and their creative potential was precisely why the idea arose to get them involved, says Jacopo Buongiorno, the director of science and technology at NRL and Tokyo Electric Power Company Professor in Nuclear Engineering. “Involvement in real-world projects that answer questions about feasibility and cost of new technology and capabilities is a key element of a successful undergraduate education at MIT,” Buongiorno says.

      Students say it would have been impossible to tackle the problem without the help of co-instructor Boris Khaykovich, a research scientist at NRL who specializes in neutron instrumentation.

      Over the past two decades, Khaykovich has watched as SANS became the most popular technique for analyzing material structure. As the amount of available SANS beam time at the few facilities that exist became more competitive, access declined. Today only the experiments passing the most stringent review get access. What Khaykovich hopes to bring to MIT is improved access to SANS by designing an instrument that will be suitable for a majority of run-of-the-mill experiments, even if it’s not as powerful as state-of-the-art national SANS facilities. Such an instrument can still serve a wider range of researchers who currently have few opportunities to pursue SANS experiments.

      “In the U.S., we don’t have a simple, small, day-to-day SANS instrument,” Khaykovich says.

      With Khaykovich’s help, nuclear engineering undergraduate student Liam Hines says his team was able to go much further with their assessment than they would’ve starting from scratch, with no background in SANS. This project was unlike anything they’d ever been asked of as MIT students, and for students like Hines, who contributed to NRL research his entire time on campus, it was a project that hit close to home. “We were imagining this thing that might be designed at MIT,” Hines says.

      Fisher and Hines were joined by undergraduate nuclear engineering student team members Francisco Arellano, Jovier Jimenez, and Brendan Vaughan. Together, they devised a design that surprised both Khaykovich and Hartwig, identifying creative solutions that overcame all limitations and significantly reduced cost.

      Their team’s final project featured an adaptation of a conical design that was recently experimentally tested in Japan, but not generally used. The conical design allowed them to maximize precision while working within the other constraints, resulting in an instrument design that exceeded Hartwig’s expectations. The students also showed the feasibility of using an alternative type of glass-based low-cost neutron detector to calibrate the scattering data. By avoiding the need for a traditional detector based on helium-3, which is increasingly scarce and exorbitantly expensive, such a detector would dramatically reduce cost and increase availability. Their final presentation indicated the day-to-day SANS instrument could be built at only 4.5 meters long and with an estimated cost less than $1 million.

      Khaykovich credited the students for their enthusiasm, bouncing ideas off each other and exploring as much terrain as possible by interviewing experts who implemented SANS at other facilities. “They showed quite a perseverance and an ability to go deep into a very unfamiliar territory for them,” Khaykovich says.

      Hines says that Hartwig emphasized the importance of fielding expert opinions to more quickly discover optimal solutions. Fisher says that based on their research, if their design is funded, it would make SANS “more accessible to research for the sake of knowledge,” rather than dominated by industry research.

      Hartwig and Khaykovich agreed the students’ final project results showed a baseline of how MIT could pursue SANS technology cheaply, and when NRL proceeds with its own design process, Hartwig says, “The student’s work might actually change the cost of the feasibility of this at MIT in a way that if we hadn’t run the class, we would never have thought about doing.”

      Buongiorno says as they move forward with the project, NRL staff will consult students’ findings.

      “Indeed, the students developed original technical approaches, which are now being further explored by the NRL staff and may ultimately lead to the deployment of this new important capability on the MIT campus,” Buongiorno says.

      Hartwig says it’s a goal of the Nuclear Systems Design Project course to empower students to learn how to lead teams and embrace challenges, so they can be effective leaders advancing novel solutions in research and industry. “I think it helps teach people to be agile, to be flexible, to have confidence that they can actually go off and learn what they don’t know and solve problems they may think are bigger than themselves,” he says.

      It’s common for past classes of Nuclear Systems Design Project students to continue working on ideas beyond the course, and some students have even launched companies from their project research. What’s less common is for Hartwig’s students to actively serve as engineers pointed to a particular campus problem that’s expected to be resolved in the next few years.

      “In this case, they’re actually working on something real,” Hartwig says. “Their ideas are going to very much influence what we hope will be a facility that gets built at the reactor.”

      For students, it was exciting to inform a major instrument proposal that will soon be submitted to federal funding agencies, and for Hines, it became a chance to make his mark at NRL.

      “This is a lab I’ve been contributing to my entire time at MIT, and then through this project, I finished my time at MIT contributing in a much larger sense,” Hines says. More

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      in Energy

      Evan Leppink: Seeking a way to better stabilize the fusion environment

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      “Fusion energy was always one of those kind-of sci-fi technologies that you read about,” says nuclear science and engineering PhD candidate Evan Leppink. He’s recalling the time before fusion became a part of his daily hands-on experience at MIT’s Plasma Science and Fusion Center, where he is studying a unique way to drive current in a tokamak plasma using radiofrequency (RF) waves. 

      Now, an award from the U.S. Department of Energy’s (DOE) Office of Science Graduate Student Research (SCGSR) Program will support his work with a 12-month residency at the DIII-D National Fusion Facility in San Diego, California.

      Like all tokamaks, DIII-D generates hot plasma inside a doughnut-shaped vacuum chamber wrapped with magnets. Because plasma will follow magnetic field lines, tokamaks are able to contain the turbulent plasma fuel as it gets hotter and denser, keeping it away from the edges of the chamber where it could damage the wall materials. A key part of the tokamak concept is that part of the magnetic field is created by electrical currents in the plasma itself, which helps to confine and stabilize the configuration. Researchers often launch high-power RF waves into tokamaks to drive that current.

      Leppink will be contributing to research, led by his MIT advisor Steve Wukitch, that pursues launching RF waves in DIII-D using a unique compact antenna placed on the tokamak center column. Typically, antennas are placed inside the tokamak on the outer edge of the doughnut, farthest from the central hole (or column), primarily because access and installation are easier there. This is known as the “low-field side,” because the magnetic field is lower there than at the central column, the “high-field side.” This MIT-led experiment, for the first time, will mount an antenna on the high-field side. There is some theoretical evidence that placing the wave launcher there could improve power penetration and current drive efficiency. And because the plasma environment is less harsh on this side, the antenna will survive longer, a factor important for any future power-producing tokamak.

      Leppink’s work on DIII-D focuses specifically on measuring the density of plasmas generated in the tokamak, for which he developed a “reflectometer.” This small antenna launches microwaves into the plasma, which reflect back to the antenna to be measured. The time that it takes for these microwaves to traverse the plasma provides information about the plasma density, allowing researchers to build up detailed density profiles, data critical for injecting RF power into the plasma.

      “Research shows that when we try to inject these waves into the plasma to drive the current, they can lose power as they travel through the edge region of the tokamak, and can even have problems entering the core of the plasma, where we would most like to direct them,” says Leppink. “My diagnostic will measure that edge region on the high-field side near the launcher in great detail, which provides us a way to directly verify calculations or compare actual results with simulation results.”

      Although focused on his own research, Leppink has excelled at priming other students for success in their studies and research. In 2021 he received the NSE Outstanding Teaching Assistant and Mentorship Award.

      “The highlights of TA’ing for me were the times when I could watch students go from struggling with a difficult topic to fully understanding it, often with just a nudge in the right direction and then allowing them to follow their own intuition the rest of the way,” he says.

      The right direction for Leppink points toward San Diego and RF current drive experiments on DIII-D. He is grateful for the support from the SCGSR, a program created to prepare graduate students like him for science, technology, engineering, or mathematics careers important to the DOE Office of Science mission. It provides graduate thesis research opportunities through extended residency at DOE national laboratories. He has already made several trips to DIII-D, in part to install his reflectometer, and has been impressed with the size of the operation.

      “It takes a little while to kind of compartmentalize everything and say, ‘OK, well, here’s my part of the machine. This is what I’m doing.’ It can definitely be overwhelming at times. But I’m blessed to be able to work on what has been the workhorse tokamak of the United States for the past few decades.” More

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      in Environment

      Helping renewable energy projects succeed in local communities

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      Jungwoo Chun makes surprising discoveries about sustainability initiatives by zooming in on local communities.

      His discoveries lie in understanding how renewable energy infrastructure develops at a local level. With so many stakeholders in a community — citizens, government officials, businesses, and other organizations — the development process gets complicated very quickly. Chun works to unpack stakeholder relationships to help local renewable energy projects move forward.

      While his interests today are in local communities around the U.S., Chun comes from a global background. Growing up, his family moved frequently due to his dad’s work. He lived in Seoul, South Korea until elementary school and then hopped from city to city around Asia, spending time in China, Hong Kong, and Singapore. When it was time for college, he returned to South Korea, majoring in international studies at Korea University and later completing his master’s there in the same field.

      After graduating, Chun wanted to leverage his international expertise to tackle climate change. So, he pursued a second master’s in international environmental policy with William Moomaw at Tufts University.

      During that time, Chun came across an article on climate change by David Victor, a professor in public policy at the University of California at San Diego. Victor argued that while international efforts to fight climate change are necessary, more tangible progress can be made through local efforts catered to each country. That prompted Chun to think a step further: “What can we do in the local community to make a little bit of a difference, which could add up to something big in the long term?”

      With a renewed direction for his goals, Chun arrived at the MIT Department of Urban Studies and Planning, specializing in environmental policy and planning. But he was still missing that final inspirational spark to proactively pursue his goals — until he began working with his primary advisor, Lawrence Susskind, the Ford Professor of Urban and Environmental Planning and director of the Science Impact Collaborative.

      For previous research projects, “I would just do what I was told,” Chun says, but his new advisor “really opened [his] eyes” to being an active member of the community. From the start, Susskind has encouraged Chun to share his research ideas and has shown him how to leverage his research skills for public service. Over the past few years, Chun has also taught several classes with Susskind, learning to approach education thoughtfully for an engaging and equitable classroom. Because of their relationship, Chun now always searches for ways to make a difference through research, teaching, and public service.

      Understanding renewable energy projects at a local level

      For his main dissertation project with Susskind, Chun is studying community-owned solar energy projects, working to understand what makes them successful.

      Often, communities don’t have the required expertise to carry out these projects on their own and instead look to advisory organizations for help. But little research has been done on these organizations and the roles that they play in developing solar energy infrastructure.

      Through over 200 surveys and counting, Chun has discovered that these organizations act as life-long collaborators to communities and are critical in getting community-owned solar projects up and running. At the start of these projects, they walk communities through a mountain of logistics for setting up solar energy infrastructure, including permit applications, budgeting, and contractor employment. After the infrastructure is in place, the organizations stay involved, serving as consultants when needed and sometimes even becoming partners.

      Because of these roles, Chun calls these organizations “intermediaries,” drawing a parallel with roles in in conflict resolution. “But it’s much more than that,” he adds. Intermediaries help local communities “build a movement [for community-owned solar energy projects] … and empower them to be independent and self-sustaining.”

      Chun is also working on another project with Susskind, looking at situations where communities are opposed to renewable energy infrastructure. For this project, Chun is supervising and mentoring a group of five undergraduates. Together, they are trying to pinpoint the reasons behind local opposition to renewable energy projects.

      The idea for this project emerged two years ago, when Chun heard in the news that many solar and wind projects were being delayed or cancelled due to local opposition. But the reasons for this opposition weren’t thoroughly researched.

      “When we started to dig a little deeper, [we found that] communities oppose these projects even though they aren’t opposed to renewable energy,” Chun says. The primary reasons for opposition lie in land use concerns, including financial challenges, health and safety concerns, and ironically, environmental consequences. By better understanding these concerns, Chun hopes to help more renewable energy projects succeed and bring society closer to a sustainable future.

      Bringing research to the classroom and community

      Right now, Chun is looking to bring his research insights on renewable energy infrastructure into the classroom. He’s developing a course on renewable energy that will act as a “clinic” where students will work with communities to understand their concerns for potential renewable energy projects. The students’ findings will then be passed onto project leaders to help them address these concerns.

      This new course is modeled after 11.074/11.274 (Cybersecurity Clinic), which Chun has helped develop over the past few years. In this clinic, students work with local governments in New England to assess potential cybersecurity vulnerabilities in their digital systems. At first, “a lot of city governments were very skeptical, like ‘students doing service for us…?’” Chun says. “But in the end, they were all very satisfied with the outcome” and found the assessments “impactful.”

      Since the Cybersecurity Clinic has kicked off, other universities have approached Chun and his co-instructors about developing their own regional clinics. Now, there are cybersecurity clinics operating around the world. “That’s been a huge success,” Chun says. Going forward, “we’d like to expand the benefit of this clinic [to address] communities opposing renewable energy [projects].” The new course will be a philosophical trifecta for Chun, combining his commitments to research, teaching, and public service.

      Chun plans to wrap up his PhD at the end of this summer and is currently writing his dissertation on community-owned solar energy projects. “I’m done with all the background work — working the soil and throwing the seeds in the right place,” he says, “It’s now time to gather all the crops and present the work.” More

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      in Environment

      “The world needs your smarts, your skills,” Ngozi Okonjo-Iweala tells MIT’s Class of 2022

      by

      On a clear warm day, the MIT graduating class of 2022 gathered in Killian Court for the first in-person commencement exercises in three years, after two years of online ceremonies due to the Covid-19 pandemic.

      Ngozi Okonjo-Iweala MCP ’78, PhD ’81, director-general of the World Trade Organization, delivered the Commencement address, stressing the global need for science-informed policy to address problems of climate change, pandemics, international security, and wealth disparities. She told the graduates: “In these uncertain times, in this complex world in which you are entering, you need not be so daunted, if you can search for the opportunities hidden in challenges.” She urged them to go “into the world to embrace the opportunities to serve.”

      An expert in global finance, economics, and international development, Okonjo-Iweala is the first woman and first African to lead the WTO. She earned a master’s degree in city planning from MIT in 1978, and a PhD in regional economics and development in 1981.

      Okonjo-Iweala began her address by paying tribute to MIT President L. Rafael Reif, who earlier this semester announced plans to end his decade-long tenure in that role. Calling this a “bittersweet day” because of his departure, she honored “his academic, institutional, and thought leadership of these past 10 years.”

      She spoke warmly of the way MIT had helped her while she was a graduate student struggling to pay the bills. She was assured that the Institute would do whatever was needed to make sure she could complete her studies, she recalled, saying, “They had my back.” Noting that this year’s graduating class had their own educational journeys challenged by the global pandemic, she described how her own early education was interrupted for three years by civil war in her home country of Nigeria. She also noted the recent tragic shootings in Uvalde, Texas, saying that “I feel grief as a mother and a grandmother.”

      “MIT has helped make me who I am today,” she said. “My parents made it clear to me that education was a privilege, and that with that privilege comes responsibility — the responsibility to use it for others, not just for yourself.”

      She said that what the world needs in this time of multiple global challenges, including Covid-19, climate change, public health, and international security, is an approach “combining science, social science, and public policy, to meet the challenges of our future.”

      Friday’s Commencement ceremony celebrated the 1,099 undergraduate and 2,590 graduate students receiving MIT diplomas this year.

      Photo: Gretchen Ertl

      MIT President L. Rafael Reif walked near the head of the procession to Killian Court, followed by Commencement speaker Ngozi Okonjo-Iweala, MIT Chancellor Melissa Nobles, and others.

      Photo: Adam Glanzman

      Temiloluwa Omitoogun, president of the Class of 2022, told his classmates, “MIT is hard. MIT during an unprecedented pandemic is even harder, but we did it.”

      Photo: Adam Glanzman

      In a longstanding MIT Commencement ritual, graduates turn over their class ring, the “brass rat.” The ring’s image of the Boston skyline faces students until they graduate, and thereafter they will see the Cambridge skyline, in effect looking back at campus.

      Photo: Adam Glanzman

      Members of the Class of 2022 celebrated on Killian Court.

      Photo: Adam Glanzman

      Fifty years after their own graduation, members of the Class of 1972 attended the ceremony as special guests, wearing signature red jackets. Members of the Classes of ’70 and ’71 also joined the festivities.

      Photo: Gretchen Ertl

      Members of the Class of 2022 celebrated on Killian Court.

      Photo: Gretchen Ertl

      President Reif urged the assembled graduates to shout out a loud “thank you!” to all family, professors, friends, and others who helped them reach today’s milestone.

      Photo: Gretchen Ertl

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      Okonjo-Iweala, who was formerly head of the World Bank, said that “a common thread running through many of these challenges is the central role for science,” and she stressed the need for technological innovation to address the global problems facing humanity. “New inventions and new ways of doing things will have an impact, mainly to the extent they are scaled up across the dividing lines of income and geography,” she said.

      “We don’t just need vaccines,” she continued. “We need shots in arms across the world, to be safe. We need new renewable technologies diffused not just in rich countries to fight climate change, but also in poor ones. We need new agricultural technologies built to local conditions and culture, if we’re to fight hunger. In other words, we need innovation. But we also need access, equity, diffusion.”

      In the case of the global response to the pandemic, she noted that only 17 percent of people in Africa and 13 percent of people in low-income countries have been fully vaccinated, compared to 75 percent of people in high income countries. “Since we all know that no one is safe until everyone is safe, the risk of more dangerous variants and pathogens remains real because of this public policy lapse and the lack of timely international cooperation,” she said.

      As for climate change, she pointed out that the world somehow managed to come up with $14 trillion to address the Covid-19 pandemic but has not managed to fulfill the pledges nations made to provide $100 billion to help less-developed nations build renewable energy solutions.

      To address these global challenges, she told the new graduates, “the world needs your smarts, your skills, your adaptability, and the great training you have received here at MIT. The world needs you for innovation, for policymaking, for connecting the dots so that implementation can actually happen.”

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      President Reif, in his charge to the graduates, urged the assembled crowd to shout out a loud “thank you!” to all family, professors, friends, and other who helped them reach today’s milestone. He pointed out that research, including from MIT’s Department of Brain and Cognitive Sciences, shows that “simply expressing gratitude does wonderful things to your brain. It gets different parts of your brain to act in a synchronized way. It lights up reward pathways!”

      “All of us could use a reliable device for feeling better. So now, thanks to brain science, Course 9, you have one! The Gratitude Amplifier is unbreakable. Its battery never dies, it will never try to sell you anything, you can use it every day, forever — and it’s free!”

      He recalled the example of the way students banded together to create a new space for relaxation on campus, now known as the Banana Lounge, a central location where students could relax with free coffee and bananas. “The students have done this all essentially themselves, applying their skills and the most delightful MIT values.” The project has already distributed a half-million bananas, he said, and produced a “wonderful, tropical, perfectly improbable new MIT institution.”

      He urged the graduating students to work to “make the world a little more like MIT. More daring and more passionate. More rigorous, inventive and ambitious. More humble, more respectful, more generous, more kind.” And, he added, “try always to share your bananas!”

      Adam Joseph “AJ” Miller, president of the Graduate Student Council, said, “Today marks the end of a chapter, the culmination of so many late nights, to forge lifelong friendships, to hold onto new experiences, to shape our dreams.” He added that “Something I heard a lot about when I first got here was all the doubt so many of us had in ourselves. I can say unequivocally today though, there are no impostors before me. Nobody sits where you sit by accident. You’re all now graduates of MIT, carrying on an incredibly impressive history.”

      Miller urged his fellow students to “stay confident in yourselves because of the challenges you’ve overcome. Be courageous in trying, because failure is learning and investing in each other.”

      Temiloluwa Omitoogun, president of the Class of 2022, told his classmates, “MIT is hard. MIT during an unprecedented pandemic is even harder, but we did it. Even if you don’t realize it, this is a huge accomplishment.” He added that “it’s sad that we’re all parting ways at the moment, but I’m even more excited than sad. I’m excited to see what more you all will accomplish. I look out and I don’t just see friends and classmates. I see future leaders, people who will change the world. I’m going to try my best to keep up and change the world too.”

      Later in the day, in a separate ceremony on Briggs Field, each of the members of the undergraduate Class of 2022 had a chance to hear their names read aloud as they walked across the stage to receive their diplomas. Right before this presentation, senior and physics and mathematics major Quinn Brodsky performed a heartful rendition of “Hypotheticals” by Lake Street Dive.

      Addressing the graduating seniors, Chancellor Melissa Nobles urged them to “absorb and relish this celebration of what you’ve achieved during your transformative time at MIT. How much you have grown, academically, professionally and personally!” She added that “the lifelong friends and mentors you found here are the people who I know will continue to be sources of encouragement, support, and inspiration as you make your way in the world.”

      Recalling the way the pandemic altered their academic careers, she said “you should know now that you can handle whatever life throws your way. Never forget that you are stronger and more resilient than you think you are.” She added, “hold on to the way this pandemic has put certain things into perspective. Time with people we care about is precious. So are our health and wellbeing, and the health and wellbeing of the ones we love. Looking out for others and feeling a sense of shared responsibility for the common good are paramount.”

      Nobles concluded that “your journey into the future holds countless possibilities, risks, joys, rewards, sometimes failures, and always surprises. … We wish you well on the road ahead.” More