More stories

  • in

    Researchers develop a detector for continuously monitoring toxic gases

    Most systems used to detect toxic gases in industrial or domestic settings can be used only once, or at best a few times. Now, researchers at MIT have developed a detector that could provide continuous monitoring for the presence of these gases, at low cost.The new system combines two existing technologies, bringing them together in a way that preserves the advantages of each while avoiding their limitations. The team used a material called a metal-organic framework, or MOF, which is highly sensitive to tiny traces of gas but whose performance quickly degrades, and combined it with a polymer material that is highly durable and easier to process, but much less sensitive.The results are reported today in the journal Advanced Materials, in a paper by MIT professors Aristide Gumyusenge, Mircea Dinca, Heather Kulik, and Jesus del Alamo, graduate student Heejung Roh, and postdocs Dong-Ha Kim, Yeongsu Cho, and Young-Moo Jo.Highly porous and with large surface areas, MOFs come in a variety of compositions. Some can be insulators, but the ones used for this work are highly electrically conductive. With their sponge-like form, they are effective at capturing molecules of various gases, and the sizes of their pores can be tailored to make them selective for particular kinds of gases. “If you are using them as a sensor, you can recognize if the gas is there if it has an effect on the resistivity of the MOF,” says Gumyusenge, the paper’s senior author and the Merton C. Flemings Career Development Assistant Professor of Materials Science and Engineering.The drawback for these materials’ use as detectors for gases is that they readily become saturated, and then can no longer detect and quantify new inputs. “That’s not what you want. You want to be able to detect and reuse,” Gumyusenge says. “So, we decided to use a polymer composite to achieve this reversibility.”The team used a class of conductive polymers that Gumyusenge and his co-workers had previously shown can respond to gases without permanently binding to them. “The polymer, even though it doesn’t have the high surface area that the MOFs do, will at least provide this recognize-and-release type of phenomenon,” he says.The team combined the polymers in a liquid solution along with the MOF material in powdered form, and deposited the mixture on a substrate, where they dry into a uniform, thin coating. By combining the polymer, with its quick detection capability, and the more sensitive MOFs, in a one-to-one ratio, he says, “suddenly we get a sensor that has both the high sensitivity we get from the MOF and the reversibility that is enabled by the presence of the polymer.”The material changes its electrical resistance when molecules of the gas are temporarily trapped in the material. These changes in resistance can be continuously monitored by simply attaching an ohmmeter to track the resistance over time. Gumyusenge and his students demonstrated the composite material’s ability to detect nitrogen dioxide, a toxic gas produced by many kinds of combustion, in a small lab-scale device. After 100 cycles of detection, the material was still maintaining its baseline performance within a margin of about 5 to 10 percent, demonstrating its long-term use potential.In addition, this material has far greater sensitivity than most presently used detectors for nitrogen dioxide, the team reports. This gas is often detected after the use of stove ovens. And, with this gas recently linked to many asthma cases in the U.S., reliable detection in low concentrations is important. The team demonstrated that this new composite could detect, reversibly, the gas at concentrations as low as 2 parts per million.While their demonstration was specifically aimed at nitrogen dioxide, Gumyusenge says, “we can definitely tailor the chemistry to target other volatile molecules,” as long as they are small polar analytes, “which tend to be most of the toxic gases.”Besides being compatible with a simple hand-held detector or a smoke-alarm type of device, one advantage of the material is that the polymer allows it to be deposited as an extremely thin uniform film, unlike regular MOFs, which are generally in an inefficient powder form. Because the films are so thin, there is little material needed and production material costs could be low; the processing methods could be typical of those used for industrial coating processes. “So, maybe the limiting factor will be scaling up the synthesis of the polymers, which we’ve been synthesizing in small amounts,” Gumyusenge says.“The next steps will be to evaluate these in real-life settings,” he says. For example, the material could be applied as a coating on chimneys or exhaust pipes to continuously monitor gases through readings from an attached resistance monitoring device. In such settings, he says, “we need tests to check if we truly differentiate it from other potential contaminants that we might have overlooked in the lab setting. Let’s put the sensors out in real-world scenarios and see how they do.”The work was supported by the MIT Climate and Sustainability Consortium (MCSC), the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) at MIT, and the U.S. Department of Energy. More

  • in

    Elaine Liu: Charging ahead

    MIT senior Elaine Siyu Liu doesn’t own an electric car, or any car. But she sees the impact of electric vehicles (EVs) and renewables on the grid as two pieces of an energy puzzle she wants to solve.The U.S. Department of Energy reports that the number of public and private EV charging ports nearly doubled in the past three years, and many more are in the works. Users expect to plug in at their convenience, charge up, and drive away. But what if the grid can’t handle it?Electricity demand, long stagnant in the United States, has spiked due to EVs, data centers that drive artificial intelligence, and industry. Grid planners forecast an increase of 2.6 percent to 4.7 percent in electricity demand over the next five years, according to data reported to federal regulators. Everyone from EV charging-station operators to utility-system operators needs help navigating a system in flux.That’s where Liu’s work comes in.Liu, who is studying mathematics and electrical engineering and computer science (EECS), is interested in distribution — how to get electricity from a centralized location to consumers. “I see power systems as a good venue for theoretical research as an application tool,” she says. “I’m interested in it because I’m familiar with the optimization and probability techniques used to map this level of problem.”Liu grew up in Beijing, then after middle school moved with her parents to Canada and enrolled in a prep school in Oakville, Ontario, 30 miles outside Toronto.Liu stumbled upon an opportunity to take part in a regional math competition and eventually started a math club, but at the time, the school’s culture surrounding math surprised her. Being exposed to what seemed to be some students’ aversion to math, she says, “I don’t think my feelings about math changed. I think my feelings about how people feel about math changed.”Liu brought her passion for math to MIT. The summer after her sophomore year, she took on the first of the two Undergraduate Research Opportunity Program projects she completed with electric power system expert Marija Ilić, a joint adjunct professor in EECS and a senior research scientist at the MIT Laboratory for Information and Decision Systems.Predicting the gridSince 2022, with the help of funding from the MIT Energy Initiative (MITEI), Liu has been working with Ilić on identifying ways in which the grid is challenged.One factor is the addition of renewables to the energy pipeline. A gap in wind or sun might cause a lag in power generation. If this lag occurs during peak demand, it could mean trouble for a grid already taxed by extreme weather and other unforeseen events.If you think of the grid as a network of dozens of interconnected parts, once an element in the network fails — say, a tree downs a transmission line — the electricity that used to go through that line needs to be rerouted. This may overload other lines, creating what’s known as a cascade failure.“This all happens really quickly and has very large downstream effects,” Liu says. “Millions of people will have instant blackouts.”Even if the system can handle a single downed line, Liu notes that “the nuance is that there are now a lot of renewables, and renewables are less predictable. You can’t predict a gap in wind or sun. When such things happen, there’s suddenly not enough generation and too much demand. So the same kind of failure would happen, but on a larger and more uncontrollable scale.”Renewables’ varying output has the added complication of causing voltage fluctuations. “We plug in our devices expecting a voltage of 110, but because of oscillations, you will never get exactly 110,” Liu says. “So even when you can deliver enough electricity, if you can’t deliver it at the specific voltage level that is required, that’s a problem.”Liu and Ilić are building a model to predict how and when the grid might fail. Lacking access to privatized data, Liu runs her models with European industry data and test cases made available to universities. “I have a fake power grid that I run my experiments on,” she says. “You can take the same tool and run it on the real power grid.”Liu’s model predicts cascade failures as they evolve. Supply from a wind generator, for example, might drop precipitously over the course of an hour. The model analyzes which substations and which households will be affected. “After we know we need to do something, this prediction tool can enable system operators to strategically intervene ahead of time,” Liu says.Dictating price and powerLast year, Liu turned her attention to EVs, which provide a different kind of challenge than renewables.In 2022, S&P Global reported that lawmakers argued that the U.S. Federal Energy Regulatory Commission’s (FERC) wholesale power rate structure was unfair for EV charging station operators.In addition to operators paying by the kilowatt-hour, some also pay more for electricity during peak demand hours. Only a few EVs charging up during those hours could result in higher costs for the operator even if their overall energy use is low.Anticipating how much power EVs will need is more complex than predicting energy needed for, say, heating and cooling. Unlike buildings, EVs move around, making it difficult to predict energy consumption at any given time. “If users don’t like the price at one charging station or how long the line is, they’ll go somewhere else,” Liu says. “Where to allocate EV chargers is a problem that a lot of people are dealing with right now.”One approach would be for FERC to dictate to EV users when and where to charge and what price they’ll pay. To Liu, this isn’t an attractive option. “No one likes to be told what to do,” she says.Liu is looking at optimizing a market-based solution that would be acceptable to top-level energy producers — wind and solar farms and nuclear plants — all the way down to the municipal aggregators that secure electricity at competitive rates and oversee distribution to the consumer.Analyzing the location, movement, and behavior patterns of all the EVs driven daily in Boston and other major energy hubs, she notes, could help demand aggregators determine where to place EV chargers and how much to charge consumers, akin to Walmart deciding how much to mark up wholesale eggs in different markets.Last year, Liu presented the work at MITEI’s annual research conference. This spring, Liu and Ilić are submitting a paper on the market optimization analysis to a journal of the Institute of Electrical and Electronics Engineers.Liu has come to terms with her early introduction to attitudes toward STEM that struck her as markedly different from those in China. She says, “I think the (prep) school had a very strong ‘math is for nerds’ vibe, especially for girls. There was a ‘why are you giving yourself more work?’ kind of mentality. But over time, I just learned to disregard that.”After graduation, Liu, the only undergraduate researcher in Ilić’s MIT Electric Energy Systems Group, plans to apply to fellowships and graduate programs in EECS, applied math, and operations research.Based on her analysis, Liu says that the market could effectively determine the price and availability of charging stations. Offering incentives for EV owners to charge during the day instead of at night when demand is high could help avoid grid overload and prevent extra costs to operators. “People would still retain the ability to go to a different charging station if they chose to,” she says. “I’m arguing that this works.” More

  • in

    Repurposed beer yeast may offer a cost-effective way to remove lead from water

    Every year, beer breweries generate and discard thousands of tons of surplus yeast. Researchers from MIT and Georgia Tech have now come up with a way to repurpose that yeast to absorb lead from contaminated water.Through a process called biosorption, yeast can quickly absorb even trace amounts of lead and other heavy metals from water. The researchers showed that they could package the yeast inside hydrogel capsules to create a filter that removes lead from water. Because the yeast cells are encapsulated, they can be easily removed from the water once it’s ready to drink.“We have the hydrogel surrounding the free yeast that exists in the center, and this is porous enough to let water come in, interact with yeast as if they were freely moving in water, and then come out clean,” says Patricia Stathatou, a former postdoc at the MIT Center for Bits and Atoms, who is now a research scientist at Georgia Tech and an incoming assistant professor at Georgia Tech’s School of Chemical and Biomolecular Engineering. “The fact that the yeast themselves are bio-based, benign, and biodegradable is a significant advantage over traditional technologies.”The researchers envision that this process could be used to filter drinking water coming out of a faucet in homes, or scaled up to treat large quantities of water at treatment plants.MIT graduate student Devashish Gokhale and Stathatou are the lead authors of the study, which appears today in the journal RSC Sustainability. Patrick Doyle, the Robert T. Haslam Professor of Chemical Engineering at MIT, is the senior author of the paper, and Christos Athanasiou, an assistant professor of aerospace engineering at Georgia Tech and a former visiting scholar at MIT, is also an author.Absorbing leadThe new study builds on work that Stathatou and Athanasiou began in 2021, when Athanasiou was a visiting scholar at MIT’s Center for Bits and Atoms. That year, they calculated that waste yeast discarded from a single brewery in Boston would be enough to treat the city’s entire water supply.Through biosorption, a process that is not fully understood, yeast cells can bind to and absorb heavy metal ions, even at challenging initial concentrations below 1 part per million. The MIT team found that this process could effectively decontaminate water with low concentrations of lead. However, one key obstacle remained, which was how to remove yeast from the water after they absorb the lead.In a serendipitous coincidence, Stathatou and Athanasiou happened to present their research at the AIChE Annual Meeting in Boston in 2021, where Gokhale, a student in Doyle’s lab, was presenting his own research on using hydrogels to capture micropollutants in water. The two sets of researchers decided to join forces and explore whether the yeast-based strategy could be easier to scale up if the yeast were encapsulated in hydrogels developed by Gokhale and Doyle.“What we decided to do was make these hollow capsules — something like a multivitamin pill, but instead of filling them up with vitamins, we fill them up with yeast cells,” Gokhale says. “These capsules are porous, so the water can go into the capsules and the yeast are able to bind all of that lead, but the yeast themselves can’t escape into the water.”The capsules are made from a polymer called polyethylene glycol (PEG), which is widely used in medical applications. To form the capsules, the researchers suspend freeze-dried yeast in water, then mix them with the polymer subunits. When UV light is shone on the mixture, the polymers link together to form capsules with yeast trapped inside.Each capsule is about half a millimeter in diameter. Because the hydrogels are very thin and porous, water can easily pass through and encounter the yeast inside, while the yeast remain trapped.In this study, the researchers showed that the encapsulated yeast could remove trace lead from water just as rapidly as the unencapsulated yeast from Stathatou and Athanasiou’s original 2021 study.Scaling upLed by Athanasiou, the researchers tested the mechanical stability of the hydrogel capsules and found that the capsules and the yeast inside can withstand forces similar to those generated by water running from a faucet. They also calculated that the yeast-laden capsules should be able to withstand forces generated by flows in water treatment plants serving several hundred residences.“Lack of mechanical robustness is a common cause of failure of previous attempts to scale-up biosorption using immobilized cells; in our work we wanted to make sure that this aspect is thoroughly addressed from the very beginning to ensure scalability,” Athanasiou says.After assessing the mechanical robustness of the yeast-laden capsules, the researchers constructed a proof-of-concept packed-bed biofilter, capable of treating trace lead-contaminated water and meeting U.S. Environmental Protection Agency drinking water guidelines while operating continuously for 12 days.This process would likely consume less energy than existing physicochemical processes for removing trace inorganic compounds from water, such as precipitation and membrane filtration, the researchers say.This approach, rooted in circular economy principles, could minimize waste and environmental impact while also fostering economic opportunities within local communities. Although numerous lead contamination incidents have been reported in various locations in the United States, this approach could have an especially significant impact in low-income areas that have historically faced environmental pollution and limited access to clean water, and may not be able to afford other ways to remediate it, the researchers say.“We think that there’s an interesting environmental justice aspect to this, especially when you start with something as low-cost and sustainable as yeast, which is essentially available anywhere,” Gokhale says.The researchers are now exploring strategies for recycling and replacing the yeast once they’re used up, and trying to calculate how often that will need to occur. They also hope to investigate whether they could use feedstocks derived from biomass to make the hydrogels, instead of fossil-fuel-based polymers, and whether the yeast can be used to capture other types of contaminants.“Moving forward, this is a technology that can be evolved to target other trace contaminants of emerging concern, such as PFAS or even microplastics,” Stathatou says. “We really view this as an example with a lot of potential applications in the future.”The research was funded by the Rasikbhai L. Meswani Fellowship for Water Solutions, the MIT Abdul Latif Jameel Water and Food Systems Lab (J-WAFS), and the Renewable Bioproducts Institute at Georgia Tech. More

  • in

    Scientists develop an affordable sensor for lead contamination

    Engineers at MIT, Nanytang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”Wang Qian, a principal research scientist at the Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center. More

  • in

    Two MIT PhD students awarded J-WAFS fellowships for their research on water

    Since 2014, the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) has advanced interdisciplinary research aimed at solving the world’s most pressing water and food security challenges to meet human needs. In 2017, J-WAFS established the Rasikbhai L. Meswani Water Solutions Fellowship and the J-WAFS Graduate Student Fellowship. These fellowships provide support to outstanding MIT graduate students who are pursuing research that has the potential to improve water and food systems around the world. Recently, J-WAFS awarded the 2024-25 fellowships to Jonathan Bessette and Akash Ball, two MIT PhD students dedicated to addressing water scarcity by enhancing desalination and purification processes. This work is of important relevance since the world’s freshwater supply has been steadily depleting due to the effects of climate change. In fact, one-third of the global population lacks access to safe drinking water. Bessette and Ball are focused on designing innovative solutions to enhance the resilience and sustainability of global water systems. To support their endeavors, J-WAFS will provide each recipient with funding for one academic semester for continued research and related activities.“This year, we received many strong fellowship applications,” says J-WAFS executive director Renee J. Robins. “Bessette and Ball both stood out, even in a very competitive pool of candidates. The award of the J-WAFS fellowships to these two students underscores our confidence in their potential to bring transformative solutions to global water challenges.”2024-25 Rasikbhai L. Meswani Fellowship for Water SolutionsThe Rasikbhai L. Meswani Fellowship for Water Solutions is a doctoral fellowship for students pursuing research related to water and water supply at MIT. The fellowship is made possible by Elina and Nikhil Meswani and family. Jonathan Bessette is a doctoral student in the Global Engineering and Research (GEAR) Center within the Department of Mechanical Engineering at MIT, advised by Professor Amos Winter. His research is focused on water treatment systems for the developing world, mainly desalination, or the process in which salts are removed from water. Currently, Bessette is working on designing and constructing a low-cost, deployable, community-scale desalination system for humanitarian crises.In arid and semi-arid regions, groundwater often serves as the sole water source, despite its common salinity issues. Many remote and developing areas lack reliable centralized power and water systems, making brackish groundwater desalination a vital, sustainable solution for global water scarcity. “An overlooked need for desalination is inland groundwater aquifers, rather than in coastal areas,” says Bessette. “This is because much of the population lives far enough from a coast that seawater desalination could never reach them. My work involves designing low-cost, sustainable, renewable-powered desalination technologies for highly constrained situations, such as drinking water for remote communities,” he adds.To achieve this goal, Bessette developed a batteryless, renewable electrodialysis desalination system. The technology is energy-efficient, conserves water, and is particularly suited for challenging environments, as it is decentralized and sustainable. The system offers significant advantages over the conventional reverse osmosis method, especially in terms of reduced energy consumption for treating brackish water. Highlighting Bessette’s capacity for engineering insight, his advisor noted the “simple and elegant solution” that Bessette and a staff engineer, Shane Pratt, devised that negated the need for the system to have large batteries. Bessette is now focusing on simplifying the system’s architecture to make it more reliable and cost-effective for deployment in remote areas.Growing up in upstate New York, Bessette completed a bachelor’s degree at the State University of New York at Buffalo. As an undergrad, he taught middle and high school students in low-income areas of Buffalo about engineering and sustainability. However, he cited his junior-year travel to India and his experience there measuring water contaminants in rural sites as cementing his dedication to a career addressing food, water, and sanitation challenges. In addition to his doctoral research, his commitment to these goals is further evidenced by another project he is pursuing, funded by a J-WAFS India grant, that uses low-cost, remote sensors to better understand water fetching practices. Bessette is conducting this work with fellow MIT student Gokul Sampath in order to help families in rural India gain access to safe drinking water.2024-25 J-WAFS Graduate Student Fellowship for Water and Food SolutionsThe J-WAFS Graduate Student Fellowship is supported by the J-WAFS Research Affiliate Program, which offers companies the opportunity to engage with MIT on water and food research. Current fellowship support was provided by two J-WAFS Research Affiliates: Xylem, a leading U.S.-based provider of water treatment and infrastructure solutions, and GoAigua, a Spanish company at the forefront of digital transformation in the water industry through innovative solutions. Akash Ball is a doctoral candidate in the Department of Chemical Engineering, advised by Professor Heather Kulik. His research focuses on the computational discovery of novel functional materials for energy-efficient ion separation membranes with high selectivity. Advanced membranes like these are increasingly needed for applications such as water desalination, battery recycling, and removal of heavy metals from industrial wastewater. “Climate change, water pollution, and scarce freshwater reserves cause severe water distress for about 4 billion people annually, with 2 billion in India and China’s semiarid regions,” Ball notes. “One potential solution to this global water predicament is the desalination of seawater, since seawater accounts for 97 percent of all water on Earth.”Although several commercial reverse osmosis membranes are currently available, these membranes suffer several problems, like slow water permeation, permeability-selectivity trade-off, and high fabrication costs. Metal-organic frameworks (MOFs) are porous crystalline materials that are promising candidates for highly selective ion separation with fast water transport due to high surface area, the presence of different pore windows, and the tunability of chemical functionality.In the Kulik lab, Ball is developing a systematic understanding of how MOF chemistry and pore geometry affect water transport and ion rejection rates. By the end of his PhD, Ball plans to identify existing, best-performing MOFs with unparalleled water uptake using machine learning models, propose novel hypothetical MOFs tailored to specific ion separations from water, and discover experimental design rules that enable the synthesis of next-generation membranes.  Ball’s advisor praised the creativity he brings to his research, and his leadership skills that benefit her whole lab. Before coming to MIT, Ball obtained a master’s degree in chemical engineering from the Indian Institute of Technology (IIT) Bombay and a bachelor’s degree in chemical engineering from Jadavpur University in India. During a research internship at IIT Bombay in 2018, he worked on developing a technology for in situ arsenic detection in water. Like Bessette, he noted the impact of this prior research experience on his interest in global water challenges, along with his personal experience growing up in an area in India where access to safe drinking water was not guaranteed. More

  • in

    William Green named director of MIT Energy Initiative

    MIT professor William H. Green has been named director of the MIT Energy Initiative (MITEI).In appointing Green, then-MIT Vice President for Research Maria Zuber highlighted his expertise in chemical kinetics — the understanding of the rates of chemical reactions — and the work of his research team in reaction kinetics, quantum chemistry, numerical methods, and fuel chemistry, as well as his work performing techno-economic assessments of proposed fuel and vehicle changes and biofuel production options.“Bill has been an active participant in MITEI; his broad view of energy science and technology will be a major asset and will position him well to contribute to the success of MIT’s exciting new Climate Project,” Zuber wrote in a letter announcing the appointment, which went into effect April 1. Green is the Hoyt C. Hottel Professor of Chemical Engineering and previously served as the executive officer of the MIT Department of Chemical Engineering from 2012 to 2015. He sees MITEI’s role today as bringing together the voices of engineering, science, industry, and policy to quickly drive the global energy transition.“MITEI has a very important role in fostering the energy and climate innovations happening at MIT and in building broader consensus, first in the engineering community and then ultimately to start the conversations that will lead to public acceptance and societal consensus,” says Green.Achieving consensus much more quickly is essential, says Green, who noted that it was during the 1992 Rio Summit that globally we recognized the problem of greenhouse gas emissions, yet almost a quarter-century passed before the Paris Agreement came into force. Eight years after the Paris Agreement, there is still disagreement over how to address this challenge in most sectors of the economy, and much work to be done to translate the Paris pledges into reality.“Many people feel we’re collectively too slow in dealing with the climate problem,” he says. “It’s very important to keep helping the research community be more effective and faster to provide the solutions that society needs, but we also need to work on being faster at reaching consensus around the good solutions we do have, and supporting them so they’ll actually be economically attractive so that investors can feel safe to invest in them, and to change regulations to make them feasible, when needed.”With experience in industry, policy, and academia, Green is well positioned to facilitate this acceleration. “I can see the situation from the point of view of a scientist, from the point of view of an engineer, from the point of view of the big companies, from the point of view of a startup company, and from the point of view of a parent concerned about the effects of climate change on the world my children are inheriting,” he says.Green also intends to extend MITEI’s engagement with a broader range of countries, industries, and economic sectors as MITEI focuses on decarbonization and accelerating the much-needed energy transition worldwide.Green received a PhD in physical chemistry from the University of California at Berkeley and a BA in chemistry from Swarthmore College. He joined MIT in 1997. He is the recipient of the AIChE’s R.H. Wilhelm Award in Chemical Reaction Engineering and is an inaugural Fellow of the Combustion Institute.He succeeds Robert Stoner, who served as interim director of MITEI beginning in July 2023, when longtime director Robert C. Armstrong retired after serving in the role for a decade. More

  • in

    HPI-MIT design research collaboration creates powerful teams

    The recent ransomware attack on ChangeHealthcare, which severed the network connecting health care providers, pharmacies, and hospitals with health insurance companies, demonstrates just how disruptive supply chain attacks can be. In this case, it hindered the ability of those providing medical services to submit insurance claims and receive payments.This sort of attack and other forms of data theft are becoming increasingly common and often target large, multinational corporations through the small and mid-sized vendors in their corporate supply chains, enabling breaks in these enormous systems of interwoven companies.Cybersecurity researchers at MIT and the Hasso Plattner Institute (HPI) in Potsdam, Germany, are focused on the different organizational security cultures that exist within large corporations and their vendors because it’s that difference that creates vulnerabilities, often due to the lack of emphasis on cybersecurity by the senior leadership in these small to medium-sized enterprises (SMEs).Keri Pearlson, executive director of Cybersecurity at MIT Sloan (CAMS); Jillian Kwong, a research scientist at CAMS; and Christian Doerr, a professor of cybersecurity and enterprise security at HPI, are co-principal investigators (PIs) on the research project, “Culture and the Supply Chain: Transmitting Shared Values, Attitudes and Beliefs across Cybersecurity Supply Chains.”Their project was selected in the 2023 inaugural round of grants from the HPI-MIT Designing for Sustainability program, a multiyear partnership funded by HPI and administered by the MIT Morningside Academy for Design (MAD). The program awards about 10 grants annually of up to $200,000 each to multidisciplinary teams with divergent backgrounds in computer science, artificial intelligence, machine learning, engineering, design, architecture, the natural sciences, humanities, and business and management. The 2024 Call for Applications is open through June 3.Designing for Sustainability grants support scientific research that promotes the United Nations’ Sustainable Development Goals (SDGs) on topics involving sustainable design, innovation, and digital technologies, with teams made up of PIs from both institutions. The PIs on these projects, who have common interests but different strengths, create more powerful teams by working together.Transmitting shared values, attitudes, and beliefs to improve cybersecurity across supply chainsThe MIT and HPI cybersecurity researchers say that most ransomware attacks aren’t reported. Smaller companies hit with ransomware attacks just shut down, because they can’t afford the payment to retrieve their data. This makes it difficult to know just how many attacks and data breaches occur. “As more data and processes move online and into the cloud, it becomes even more important to focus on securing supply chains,” Kwong says. “Investing in cybersecurity allows information to be exchanged freely while keeping data safe. Without it, any progress towards sustainability is stalled.”One of the first large data breaches in the United States to be widely publicized provides a clear example of how an SME cybersecurity can leave a multinational corporation vulnerable to attack. In 2013, hackers entered the Target Corporation’s own network by obtaining the credentials of a small vendor in its supply chain: a Pennsylvania HVAC company. Through that breach, thieves were able to install malware that stole the financial and personal information of 110 million Target customers, which they sold to card shops on the black market.To prevent such attacks, SME vendors in a large corporation’s supply chain are required to agree to follow certain security measures, but the SMEs usually don’t have the expertise or training to make good on these cybersecurity promises, leaving their own systems, and therefore any connected to them, vulnerable to attack.“Right now, organizations are connected economically, but not aligned in terms of organizational culture, values, beliefs, and practices around cybersecurity,” explains Kwong. “Basically, the big companies are realizing the smaller ones are not able to implement all the cybersecurity requirements. We have seen some larger companies address this by reducing requirements or making the process shorter. However, this doesn’t mean companies are more secure; it just lowers the bar for the smaller suppliers to clear it.”Pearlson emphasizes the importance of board members and senior management taking responsibility for cybersecurity in order to change the culture at SMEs, rather than pushing that down to a single department, IT office, or in some cases, one IT employee.The research team is using case studies based on interviews, field studies, focus groups, and direct observation of people in their natural work environments to learn how companies engage with vendors, and the specific ways cybersecurity is implemented, or not, in everyday operations. The goal is to create a shared culture around cybersecurity that can be adopted correctly by all vendors in a supply chain.This approach is in line with the goals of the Charter of Trust Initiative, a partnership of large, multinational corporations formed to establish a better means of implementing cybersecurity in the supply chain network. The HPI-MIT team worked with companies from the Charter of Trust and others last year to understand the impacts of cybersecurity regulation on SME participation in supply chains and develop a conceptual framework to implement changes for stabilizing supply chains.Cybersecurity is a prerequisite needed to achieve any of the United Nations’ SDGs, explains Kwong. Without secure supply chains, access to key resources and institutions can be abruptly cut off. This could include food, clean water and sanitation, renewable energy, financial systems, health care, education, and resilient infrastructure. Securing supply chains helps enable progress on all SDGs, and the HPI-MIT project specifically supports SMEs, which are a pillar of the U.S. and European economies.Personalizing product designs while minimizing material wasteIn a vastly different Designing for Sustainability joint research project that employs AI with engineering, “Personalizing Product Designs While Minimizing Material Waste” will use AI design software to lay out multiple parts of a pattern on a sheet of plywood, acrylic, or other material, so that they can be laser cut to create new products in real time without wasting material.Stefanie Mueller, the TIBCO Career Development Associate Professor in the MIT Department of Electrical Engineering and Computer Science and a member of the Computer Science and Artificial Intelligence Laboratory, and Patrick Baudisch, a professor of computer science and chair of the Human Computer Interaction Lab at HPI, are co-PIs on the project. The two have worked together for years; Baudisch was Mueller’s PhD research advisor at HPI.Baudisch’s lab developed an online design teaching system called Kyub that lets students design 3D objects in pieces that are laser cut from sheets of wood and assembled to become chairs, speaker boxes, radio-controlled aircraft, or even functional musical instruments. For instance, each leg of a chair would consist of four identical vertical pieces attached at the edges to create a hollow-centered column, four of which will provide stability to the chair, even though the material is very lightweight.“By designing and constructing such furniture, students learn not only design, but also structural engineering,” Baudisch says. “Similarly, by designing and constructing musical instruments, they learn about structural engineering, as well as resonance, types of musical tuning, etc.”Mueller was at HPI when Baudisch developed the Kyub software, allowing her to observe “how they were developing and making all the design decisions,” she says. “They built a really neat piece for people to quickly design these types of 3D objects.” However, using Kyub for material-efficient design is not fast; in order to fabricate a model, the software has to break the 3D models down into 2D parts and lay these out on sheets of material. This takes time, and makes it difficult to see the impact of design decisions on material use in real-time.Mueller’s lab at MIT developed software based on a layout algorithm that uses AI to lay out pieces on sheets of material in real time. This allows AI to explore multiple potential layouts while the user is still editing, and thus provide ongoing feedback. “As the user develops their design, Fabricaide decides good placements of parts onto the user’s available materials, provides warnings if the user does not have enough material for a design, and makes suggestions for how the user can resolve insufficient material cases,” according to the project website.The joint MIT-HPI project integrates Mueller’s AI software with Baudisch’s Kyub software and adds machine learning to train the AI to offer better design suggestions that save material while adhering to the user’s design intent.“The project is all about minimizing the waste on these materials sheets,” Mueller says. She already envisions the next step in this AI design process: determining how to integrate the laws of physics into the AI’s knowledge base to ensure the structural integrity and stability of objects it designs.AI-powered startup design for the Anthropocene: Providing guidance for novel enterprisesThrough her work with the teams of MITdesignX and its international programs, Svafa Grönfeldt, faculty director of MITdesignX and professor of the practice in MIT MAD, has helped scores of people in startup companies use the tools and methods of design to ensure that the solution a startup proposes actually fits the problem it seeks to solve. This is often called the problem-solution fit.Grönfeldt and MIT postdoc Norhan Bayomi are now extending this work to incorporate AI into the process, in collaboration with MIT Professor John Fernández and graduate student Tyler Kim. The HPI team includes Professor Gerard de Melo; HPI School of Entrepreneurship Director Frank Pawlitschek; and doctoral student Michael Mansfeld.“The startup ecosystem is characterized by uncertainty and volatility compounded by growing uncertainties in climate and planetary systems,” Grönfeldt says. “Therefore, there is an urgent need for a robust model that can objectively predict startup success and guide design for the Anthropocene.”While startup-success forecasting is gaining popularity, it currently focuses on aiding venture capitalists in selecting companies to fund, rather than guiding the startups in the design of their products, services and business plans.“The coupling of climate and environmental priorities with startup agendas requires deeper analytics for effective enterprise design,” Grönfeldt says. The project aims to explore whether AI-augmented decision-support systems can enhance startup-success forecasting.“We’re trying to develop a machine learning approach that will give a forecasting of probability of success based on a number of parameters, including the type of business model proposed, how the team came together, the team members’ backgrounds and skill sets, the market and industry sector they’re working in and the problem-solution fit,” says Bayomi, who works with Fernández in the MIT Environmental Solutions Initiative. The two are co-founders of the startup Lamarr.AI, which employs robotics and AI to help reduce the carbon dioxide impact of the built environment.The team is studying “how company founders make decisions across four key areas, starting from the opportunity recognition, how they are selecting the team members, how they are selecting the business model, identifying the most automatic strategy, all the way through the product market fit to gain an understanding of the key governing parameters in each of these areas,” explains Bayomi.The team is “also developing a large language model that will guide the selection of the business model by using large datasets from different companies in Germany and the U.S. We train the model based on the specific industry sector, such as a technology solution or a data solution, to find what would be the most suitable business model that would increase the success probability of a company,” she says.The project falls under several of the United Nations’ Sustainable Development Goals, including economic growth, innovation and infrastructure, sustainable cities and communities, and climate action.Furthering the goals of the HPI-MIT Joint Research ProgramThese three diverse projects all advance the mission of the HPI-MIT collaboration. MIT MAD aims to use design to transform learning, catalyze innovation, and empower society by inspiring people from all disciplines to interweave design into problem-solving. HPI uses digital engineering concentrated on the development and research of user-oriented innovations for all areas of life.Interdisciplinary teams with members from both institutions are encouraged to develop and submit proposals for ambitious, sustainable projects that use design strategically to generate measurable, impactful solutions to the world’s problems. More

  • in

    Exploring frontiers of mechanical engineering

    From cutting-edge robotics, design, and bioengineering to sustainable energy solutions, ocean engineering, nanotechnology, and innovative materials science, MechE students and their advisors are doing incredibly innovative work. The graduate students highlighted here represent a snapshot of the great work in progress this spring across the Department of Mechanical Engineering, and demonstrate the ways the future of this field is as limitless as the imaginations of its practitioners.Democratizing design through AILyle RegenwetterHometown: Champaign, IllinoisAdvisor: Assistant Professor Faez AhmedInterests: Food, climbing, skiing, soccer, tennis, cookingLyle Regenwetter finds excitement in the prospect of generative AI to “democratize” design and enable inexperienced designers to tackle complex design problems. His research explores new training methods through which generative AI models can be taught to implicitly obey design constraints and synthesize higher-performing designs. Knowing that prospective designers often have an intimate knowledge of the needs of users, but may otherwise lack the technical training to create solutions, Regenwetter also develops human-AI collaborative tools that allow AI models to interact and support designers in popular CAD software and real design problems. Solving a whale of a problem Loïcka BailleHometown: L’Escale, FranceAdvisor: Daniel ZitterbartInterests: Being outdoors — scuba diving, spelunking, or climbing. Sailing on the Charles River, martial arts classes, and playing volleyballLoïcka Baille’s research focuses on developing remote sensing technologies to study and protect marine life. Her main project revolves around improving onboard whale detection technology to prevent vessel strikes, with a special focus on protecting North Atlantic right whales. Baille is also involved in an ongoing study of Emperor penguins. Her team visits Antarctica annually to tag penguins and gather data to enhance their understanding of penguin population dynamics and draw conclusions regarding the overall health of the ecosystem.Water, water anywhereCarlos Díaz-MarínHometown: San José, Costa RicaAdvisor: Professor Gang Chen | Former Advisor: Professor Evelyn WangInterests: New England hiking, biking, and dancingCarlos Díaz-Marín designs and synthesizes inexpensive salt-polymer materials that can capture large amounts of humidity from the air. He aims to change the way we generate potable water from the air, even in arid conditions. In addition to water generation, these salt-polymer materials can also be used as thermal batteries, capable of storing and reusing heat. Beyond the scientific applications, Díaz-Marín is excited to continue doing research that can have big social impacts, and that finds and explains new physical phenomena. As a LatinX person, Díaz-Marín is also driven to help increase diversity in STEM.Scalable fabrication of nano-architected materialsSomayajulu DhulipalaHometown: Hyderabad, IndiaAdvisor: Assistant Professor Carlos PortelaInterests: Space exploration, taekwondo, meditation.Somayajulu Dhulipala works on developing lightweight materials with tunable mechanical properties. He is currently working on methods for the scalable fabrication of nano-architected materials and predicting their mechanical properties. The ability to fine-tune the mechanical properties of specific materials brings versatility and adaptability, making these materials suitable for a wide range of applications across multiple industries. While the research applications are quite diverse, Dhulipala is passionate about making space habitable for humanity, a crucial step toward becoming a spacefaring civilization.Ingestible health-care devicesJimmy McRaeHometown: Woburn, MassachusettsAdvisor: Associate Professor Giovani TraversoInterests: Anything basketball-related: playing, watching, going to games, organizing hometown tournaments Jimmy McRae aims to drastically improve diagnostic and therapeutic capabilities through noninvasive health-care technologies. His research focuses on leveraging materials, mechanics, embedded systems, and microfabrication to develop novel ingestible electronic and mechatronic devices. This ranges from ingestible electroceutical capsules that modulate hunger-regulating hormones to devices capable of continuous ultralong monitoring and remotely triggerable actuations from within the stomach. The principles that guide McRae’s work to develop devices that function in extreme environments can be applied far beyond the gastrointestinal tract, with applications for outer space, the ocean, and more.Freestyle BMX meets machine learningEva NatesHometown: Narberth, Pennsylvania Advisor: Professor Peko HosoiInterests: Rowing, running, biking, hiking, bakingEva Nates is working with the Australian Cycling Team to create a tool to classify Bicycle Motocross Freestyle (BMX FS) tricks. She uses a singular value decomposition method to conduct a principal component analysis of the time-dependent point-tracking data of an athlete and their bike during a run to classify each trick. The 2024 Olympic team hopes to incorporate this tool in their training workflow, and Nates worked alongside the team at their facilities on the Gold Coast of Australia during MIT’s Independent Activities Period in January.Augmenting Astronauts with Wearable Limbs Erik BallesterosHometown: Spring, TexasAdvisor: Professor Harry AsadaInterests: Cosplay, Star Wars, Lego bricksErik Ballesteros’s research seeks to support astronauts who are conducting planetary extravehicular activities through the use of supernumerary robotic limbs (SuperLimbs). His work is tailored toward design and control manifestation to assist astronauts with post-fall recovery, human-leader/robot-follower quadruped locomotion, and coordinated manipulation between the SuperLimbs and the astronaut to perform tasks like excavation and sample handling.This article appeared in the Spring 2024 edition of the Department of Mechanical Engineering’s magazine, MechE Connects.  More