#Education Articles University

#Education Articles University

Getting more heat out of sunlight

Posted: 01 Jul 2019 08:59 PM PDT

A newly developed material that is so perfectly transparent you can barely see it could unlock many new uses for solar heat. It generates much higher temperatures than conventional solar collectors do — enough to be used for home heating or for industrial processes that require heat of more than 200 degrees Celsius (392 degrees Fahrenheit).

The key to the process is a new kind of aerogel, a lightweight material that consists mostly of air, with a structure made of silica (which is also used to make glass). The material lets sunlight pass through easily but blocks solar heat from escaping. The findings are described in the journal ACS Nano, in a paper by Lin Zhao, an MIT graduate student; Evelyn Wang, professor and head of the Department of Mechanical Engineering; Gang Chen, the Carl Richard Soderberg Professor in Power Engineering; and five others.

The key to efficient collection of solar heat, Wang explains, is being able to keep something hot internally while remaining cold on the outside. One way of doing that is using a vacuum between a layer of glass and a dark, heat-absorbing material, which is the method used in many concentrating solar collectors but is relatively expensive to install and maintain. There has been great interest in finding a less expensive, passive system for collecting solar heat at the higher temperature levels needed for space heating, food processing, or many industrial processes.

Aerogels, a kind of foam-like material made of silica particles, have been developed for years as highly efficient and lightweight insulating materials, but they have generally had limited transparency to visible light, with around a 70 percent transmission level. Wang says developing a way of making aerogels that are transparent enough to work for solar heat collection was a long and difficult process involving several researchers for about four years. But the result is an aerogel that lets through over 95 percent of incoming sunlight while maintaining its highly insulating properties.

The key to making it work was in the precise ratios of the different materials used to create the aerogel, which are made by mixing a catalyst with grains of a silica-containing compound in a liquid solution, forming a kind of gel, and then drying it to get all the liquid out, leaving a matrix that is mostly air but retains the original mixture's strength. Producing a mix that dries out much faster than those in conventional aerogels, they found, produced a gel with smaller pore spaces between its grains, and that therefore scattered the light much less.

In tests on a rooftop on the MIT campus, a passive device consisting of a heat-absorbing dark material covered with a layer of the new aerogel was able to reach and maintain a temperature of 220 C, in the middle of a Cambridge winter when the outside air was below 0 C.

Such high temperatures have previously only been practical by using concentrating systems, with mirrors to focus sunlight onto a central line or point, but this system requires no concentration, making it simpler and less costly. That could potentially make it useful for a wide variety of applications that require higher levels of heat.

For example, simple flat rooftop collectors are often used for domestic hot water, producing temperatures of around 80 C. But the higher temperatures enabled by the aerogel system could make such simple systems usable for home heating as well, and even for powering an air conditioning system. Large-scale versions could be used to provide heat for a wide variety of applications in chemical, food production, and manufacturing processes.

Zhao describes the basic function of the aerogel layer as "like a greenhouse effect. The material we use to increase the temperature acts like the Earth's atmosphere does to provide insulation, but this is an extreme example of it."

For most purposes, the passive heat collection system would be connected to pipes containing a liquid that could circulate to transfer the heat to wherever it's needed. Alternatively, Wang suggests, for some uses the system could be connected to heat pipes, devices that can transfer heat over a distance without requiring pumps or any moving parts.

Because the principle is essentially the same, an aerogel-based solar heat collector could directly replace the vacuum-based collectors used in some existing applications, providing a lower-cost option. The materials used to make the aerogel are all abundant and inexpensive; the only costly part of the process is the drying, which requires a specialized device called a critical point dryer to allow for a very precise drying process that extracts the solvents from the gel while preserving its nanoscale structure.

Because that is a batch process rather than a continuous one that could be used in roll-to-roll manufacturing, it could limit the rate of production if the system is scaled up to industrial production levels. "The key to scaleup is how we can reduce the cost of that process," Wang says. But even now, a preliminary economic analysis shows that the system can be economically viable for some uses, especially in comparison with vacuum-based systems.

The research team included research scientist Bikram Bhatia, postdoc Sungwoo Yang, graduate student Elise Strobach, instructor Lee Weinstein and postdoc Thomas Cooper. The work was primarily funded by the U.S. Department of Energy's ARPA-E program.

MIT Energy Initiative awards seven Seed Fund grants for early-stage energy research

Posted: 01 Jul 2019 10:05 AM PDT

The MIT Energy Initiative (MITEI) recently awarded seven grants totaling approximately $1 million through its Seed Fund Program, which supports early-stage innovative energy research at MIT through an annual competitive process.

"Supporting basic research has always been a core component of MITEI's mission to transform and decarbonize global energy systems," says MITEI Director Robert C. Armstrong, the Chevron Professor of Chemical Engineering. "This year's funded projects highlight just a few examples of the many ways that people working across the energy field are researching vital topics to create a better world."

The newly awarded projects will address topics such as developing efficient strategies for recycling plastics, improving the stability of high-energy metal-halogen flow batteries, and increasing the potential efficiency of silicon solar cells to accelerate the adoption of photovoltaics. Awardees include established energy faculty members and others who are new to the energy field, from disciplines including applied economics, chemical engineering, biology, and other areas.

Demand-response policies and incentives for energy efficiency adoption

Most of today's energy growth is occurring in developing countries. Assistant Professor Namrata Kala and Professor Christopher Knittel, both of whom focus on applied economics at the MIT Sloan School of Management, will use their grant to examine key policy levers for meeting electricity demand and renewable energy growth without jeopardizing system reliability in the developing world.

Kala and Knittel plan to design and run a randomized control trial in New Delhi, India, in collaboration with a large Indian power company. "We will estimate the willingness of firms to enroll in services that reduce peak consumption, and also promote energy efficiency," says Kala, the W. Maurice Young (1961) Career Development Professor of Management. "Estimating the costs and benefits of such services, and their allocation across customers and electricity providers, can inform policies that promote energy efficiency in a cost-effective manner."

Efficient conversion of methane to methanol 

Methane, the primary component of natural gas, has become an increasingly important part of the global energy portfolio. However, the chemical inertness of methane and the lack of efficient methods to convert this gaseous carbon feedstock into liquid fuels has significantly limited its application. Yang Shao-Horn, the W.M. Keck Professor of Energy in the departments of Mechanical Engineering and Materials Science and Engineering, seeks to address this problem using her seed fund grant. Shao-Horn and Shuai Yuan, a postdoc in the Research Laboratory of Electronics, will focus on achieving efficient, cost-effective gas-to-liquid conversion using metal-organic frameworks (MOFs) as electrocatalysts.

Current methane activation and conversion processes are usually accomplished by costly and energy-intensive steam reforming at elevated temperature and high pressure. Shao-Horn and Yuan's goal is to design efficient MOF-based electrocatalysts that will permit the methane-to-methanol conversion process to proceed at ambient temperature and pressure.

"If successful, this electrochemical gas-to-liquid concept could lead to a modular, efficient, and cost-effective solution that can be deployed in both large-scale industrial plants and remotely located oil fields to increase the utility of geographically isolated gas reserves," says Shao-Horn.

Using machine learning to solve the "zeolite conundrum"

The energy field is replete with opportunities for machine learning to expedite progress toward a variety of innovative energy solutions. Rafael Gómez-Bombarelli, the Toyota Assistant Professor in Materials Processing in the Department of Materials Science and Engineering, received a grant for a project that will combine machine learning and simulation to accelerate the discovery cycle of zeolites.
Zeolites are materials with wide-ranging industrial applications as catalysts and molecular sieves because of their high stability and selective nanopores that can confine small molecules. Despite decades of abundant research, only 248 zeolite frameworks have been realized out of the millions of possible structures that have been proposed using computers — the so-called zeolite conundrum.
The problem, notes Gómez-Bombarelli, is that discovery of these new frameworks has relied mostly on trial-and-error in the lab — an approach that is both slow and labor-intensive.
In his seed grant work, Gómez-Bombarelli and his team will be using theory to speed up that process. "Using machine learning and first-principles simulations, we'll design small molecules to dock on specific pores and direct the formation of targeted structures," says Gómez-Bombarelli. "This computational approach will drive new synthetic outcomes in zeolites faster."

Effective recycling of plastics

Professor Anthony Sinskey of the Department of Biology, Professor Gregory Stephanopoulos of the Department of Chemical Engineering, and graduate student Linda Zhong of biology have joined forces to address the environmental and economic problems posed by polyethylene terephthalate (PET). One of the most synthesized plastics, PET exhibits an extremely low degradation rate and its production is highly dependent on petroleum feedstocks.

"Due to the huge negative impacts of PET products, efficient recycling strategies need to be designed to decrease economic loss and adverse environmental impacts associated with single-use practices," says Sinskey.

"PET is essentially an organic polymer of terephthalic acid and ethylene glycol, both of which can be metabolized by bacteria as energy and nutrients. These capacities exist in nature, though not together," says Zhong. "Our goal is to engineer these metabolic pathways into E. coli to allow the bacterium to grow on PET. Using genetic engineering, we will introduce the PET-degrading enzymes into E. coli and ultimately transfer them into bioremediation organisms."

The long-term goal of the project is to prototype a bioprocess for closed-loop PET recycling, which will decrease the volume of discarded PET products as well as the consumption of petroleum and energy for PET synthesis.

The researchers' primary motivation in pursuing this project echoes MITEI's overarching goal for the seed fund program: to push the boundaries of research and innovation to solve global energy and climate challenges. Zhong says, "We see a dire need for this research because our world is inundated in plastic trash. We're only attempting to solve a tiny piece of the global problem, but we must try when much of what we hold dear depends on it."

The MITEI Seed Fund Program has awarded new grants each year since it was established in 2008. Funding for the grants comes chiefly from MITEI's founding and sustaining members, supplemented by gifts from generous donors. To date, MITEI has supported 177 projects with grants totaling approximately $23.6 million.

Recipients of MITEI Seed Fund grants for 2019 are:

  • "Development and prototyping of stable, safe, metal‐halogen flow batteries with high energy and power densities" — Martin Bazant of the departments of Chemical Engineering and Mathematics and T. Alan Hatton of the Department of Chemical Engineering;
  • "Silicon solar cells sensitized by exciton fission" — Marc Baldo of the Department of Electrical Engineering and Computer Science;
  • "Automatic design of structure‐directing agents for novel realizable zeolites" — Rafael Gómez‐Bombarelli of the Department of Materials Science and Engineering;
  • "Demand response, energy efficiency, and firm decisions" — Namrata Kala and Christopher Knittel of the Sloan School of Management;
  • "Direct conversion of methane to methanol by MOF‐based electrocatalysts" — Yang Shao‐Horn of the departments of Mechanical Engineering and Materials Science and Engineering;
  • "Biodegradation of plastics for efficient recycling and bioremediation" — Anthony Sinskey of the Department of Biology and Gregory Stephanopoulos of the Department of Chemical Engineering; and
  • "Asymmetric chemical doping for photocatalytic CO2 reduction" — Michael Strano of the Department of Chemical Engineering.

Lincoln Laboratory staff use race cars as a vehicle to teach coding

Posted: 01 Jul 2019 09:40 AM PDT

One Saturday this spring, toy-sized cars were zipping along the classroom floor of the Roxbury Innovation Center. However, no one was following them around with remote controls. Instead, each car used code to react autonomously to obstacles — code written by a classroom full of middle school students.

Andrew Fishberg, a staff member in the Advanced Capabilities and Systems Group at Lincoln Laboratory, had seen how students engaged with the Rapid Autonomous Complex-Environment Competing Ackermann-steering Robot (RACECAR) during the workshop at the Beaver Works Summer Institute (BWSI). However, BWSI is aimed at high school seniors who already excel in science, technology, engineering, and math, and Fishberg was worried that the program was reaching students too late in their educations to have maximum impact. "It only gets harder [to learn coding] the later you get to the students," he says. "I think the future of these things is at the middle school age."

So, with the help of a handful of volunteers including Eyassu Shimelis from the Advanced Concepts Technologies Group and several high school volunteers — almost all of whom were coincidentally named Dan — and the Timothy Smith Network, Fishberg designed a four-week program to introduce middle schoolers to coding by programming race cars.

The Timothy Smith Network is named for a wealthy merchant who spent most of his life in Roxbury, Massachusetts, and upon his death in 1918 bequeathed his estate to improve the welfare of Roxbury residents. Since 1996, that trust has been used to bring the benefits of computer technology to residents via dozens of public technology centers and educational programs. Collaboration between the Timothy Smith Network and Lincoln Laboratory could help the RACECAR program reach middle schoolers who might not otherwise have the opportunity to learn to code. "Our motto is inclusiveness," says Khalid Mustafa, the IT director of the Timothy Smith Network. "Too often we have all these rules that filter people out. How do we invite people in?"

Both groups wanted to stress accessibility. Although coding is becoming a fundamental part of a modern education, schools in communities with limited educational budgets are significantly less likely to offer computer science classes. Holding the workshop at the Roxbury Innovation Center, instead of at the Beaver Works Center in Cambridge, made it more accessible for lower-income students and students of color.

The workshop was stretched out over four hours each Saturday for a month. Between one and two dozen students attended each time. The first three workshops focused on coding basics, such as Boolean data (data that has one of two possible values, often true or false) and the difference between "or" and "exclusive or" ("exclusive or" is true if only one value is true, whereas "or" is true if at least one value is true).

"We don't want to lock anybody out because they haven't had a chance to program before, so we had to start from square one," Fishberg explains. He would teach a principle and demonstrate the code on screen at the front of the classroom, then have students call out answers to build a program together. More often than not, the code the students created wouldn't run the way they wanted it to. At that point, Fishberg would walk the students through the code, explaining the logic with which computers approach problems and allowing the students to find the bugs themselves. Usually, the code spat out numbers as expected within minutes.

On the fourth Saturday, Fishberg brought out the race cars. Slightly larger than a phone book, the cars have the wheels and body of an off-the-shelf remote-controlled car, upon which is mounted a piece of cardboard that holds a spinning lidar, a small processor, and a battery pack. The cars cost around $500 each to build and made their debut at this RACECAR middle school event as a cost-effective alternative to the race cars used at BWSI. The excitement — from the volunteers, students, and observers — was palpable. "Basically everything they've been learning … turns into the logic to drive the car," Fishberg said. "That application really drives home the learning objectives."

The race cars "see" by using lidar – each car's lidar system shoots out a pulse of laser light and measures how long it takes to bounce back. By aiming laser beams in 720 directions all around the car, the lidar system can map the distance between it and the nearest obstacles. The students began by calibrating their race cars, finding which direction marked zero degrees in the lidar's measurements by circling the car with pieces of cardstock and looking for changes in the lidar's readouts. They also calibrated the car to drive straight forward when it is prompted, and then moved on to harder coding challenges, such as having the car stop itself when it sensed an obstacle. The students were exhilarated by their successes and suggested designs for complex obstacle courses the cars could navigate. Fishberg used this as an opportunity to impart another fundamental principle of coding: KISS, or Keep It Simple, Silly.

Both Fishberg and Mustafa hope to make this year's workshop the first of many. Coding is becoming a vital skill, and introducing students to it at a young age opens doors in their education — such as to the BWSI, which is aimed at high school seniors who perform well in the STEM fields. "We're looking to expand," Mustafa says. "Our goal is to really establish this [class] as a model."

Mustafa thought that the most powerful part of the workshop and the collaboration between the Timothy Smith Network and Lincoln Laboratory was the way it brought people together who wouldn't otherwise be able to share their skills. "How do we give each other access to each other?" Mustafa asks. "That's really the key."

MIT Media Lab Director's Fellows announced for 2019

Posted: 01 Jul 2019 09:30 AM PDT

The MIT Media Lab has added 11 members to the diverse group of visionary innovators and leaders it calls the Director's Fellows.

Now in its seventh year, the Director's Fellows program links a vast array of creators, advocates, artists, scientists, educators, philosophers, and others to the lab. The goal of the program is for the fellows to get involved in the lab's work, bringing new perspectives, ideas, and knowledge to projects and initiatives.

Conversely, the fellows spread insights, knowledge, and work of the lab out into the world, giving it exposure in spaces as varied as fashion, human rights, and sports.

"My intention was to bring a wide range of voices into the Media Lab that we might not otherwise hear, because I firmly believe that technology and engineering alone cannot address the complexity of the challenges we face in today's world," says Joi Ito, director of the Media Lab. "Addressing an issue as complex as climate change or public health require solutions involving philosophy and politics and anthropology — a range of knowledge, skills, and talents that we don't necessarily have at the lab."

With the addition of this year's fellows, the Director's Fellows network will be 70-ish persons strong. The fellows may collaborate on projects with students and faculty, serve as advisers, bring a project idea into the lab, or work on projects together. Those living abroad may participate in Media Lab workshops and other offsite events.

Fellows have a formal affiliation with the lab for two years, but the hope is that the network continues to flourish after that period ends. "Our intention is to keep them as close as possible, both to each other and to the lab," says Claudia Robaina, the program's director. "They are great resources for us and for each other, a huge network of collaborators."

The fellows this year are as diverse as ever, although Robaina says there is perhaps a greater diversity of age than in the typical class. Among them are a career police officer, a freestyle skateboarder, and a physician.

The Media Lab's 2019 Directors Fellows are listed below.

Jaylen Brown, an NBA basketball player with the Boston Celtics, has a wide range of interests, including history, finance, technology, and meditation. Considered an innovator by his peers, he entered the NBA draft in 2016 without an agent, and a year later created a stir by pulling together a networking event for rookie players at the NBA Summer League, which was followed by a "Tech Hustle" event at the NBA All-Star Weekend that attracted venture capitalists, rap stars, and corporate chieftains to help players understand investment.

Jan Fuller, a former senior digital forensics investigator for the Redmond Police Department in Washington state, began conducting forensic investigations of electronic devices in 2003, when 1 gigabyte was a lot of data. Currently, she's pursuing projects aimed at improving law enforcement capabilities deployed against digital crimes and coaching and mentoring students interested in careers in digital forensics.

Kathy Jetñil-Kijiner, a poet of Marshall Islands ancestry, achieved international acclaim with her performance at the opening of the United Nations Climate Summit in New York in 2014. She has published a collection of poetry, Iep Jāltok: Poems from a Marshallese Daughter, and she directs a Marshall Islands-based nonprofit dedicated to empowering Marshallese youth to seek solutions to the environmental challenges their homeland faces.  

Ayana Elizabeth Johnson, founder and chief executive of Ocean Collectiv, a consulting firm for conservation solutions, is a marine biologist and policy expert. She founded the Urban Ocean Lab, a think tank focused on coastal cities, and has worked on ocean policy at the U.S. Environmental Protection Agency and the National Oceanic and Atmospheric Administration.

Lehua Kamalu, an apprentice navigator and the voyaging director at the Polynesian Voyaging Society, researched and devised the sail plan for Hōkūleʻa, a double hulled canoe, as it circumnavigated the Earth from 2014 to 2018 on a voyage named "Malama Honua — to care for the Earth." She sees the practice of deep-sea voyaging as a means to challenge the depth and quality of our individual relationships to the ocean, nature, and one another.

AiLun Ku, president and chief operating officer at The Opportunity Network, works to create spaces for first-generation high school and college students of color to enhance and improve their postsecondary and career readiness education. She trains partners to integrate culturally balanced, student-centered curriculum design with rigorous data-driven practices with the goal of influencing systems that have traditionally excluded young people of color from college and career opportunities.

Nonabah Lane, a member of the Navajo Nation, is a sustainability specialist and entrepreneur in environmental and culturally conscious business development, energy education, and tribal community commitment. She is a co-founder of Navajo Ethno-Agriculture, a farm that teaches Navajo culture through traditional farming and bilingual education and is active in promoting and developing tribal sustainable energy strategies.

Kate McCall-Kiley, co-founder and director at xD, an emerging technology lab within the U.S. government, works to create new environments and mechanisms for behavior change while experimenting with different ways to productively challenge convention. She served as a White House Presidential Innovation Fellow for the Obama administration, where she worked on projects including vote.gov, The Opportunity Project, worker.gov, BroadbandUSA, and Vice President Joe Biden's Cancer Moonshot.

Rodney Mullen, co-founder of one of the most dominant skateboarding companies in America, invented many of the tricks in use in skateboarding today and holds two patents related to the sport's equipment. He has pivoted to work in the open source community, where he finds many parallels between the creativity of skateboarders and hackers. He still skates two hours a day.

Elizabeth Pettit, executive director of Clínica Integral Almas in Álamos, Mexico, which works with remote indigenous communities, is a physician. Medicine and work in rural public health is a second act: Pettit previously was a designer, creating specialty materials for art and architecture and for the film and entertainment industry.

Michael Tubbs, mayor of Stockton, California, has received national attention for his ambitious progressive agenda, which includes securing $20 million to finance scholarships to triple the number of the city's students entering and graduating from college, and the country's first universal basic income pilot project. He is the youngest mayor in the history of the country to represent a city with more than 100,000 residents and is Stockton's first African-American mayor.

Learn more about all of the fellows from all seven cohorts at directorsfellows.media.mit.edu.

Taylor Fravel named director of the MIT Security Studies Program

Posted: 01 Jul 2019 08:30 AM PDT

M. Taylor Fravel, the Arthur and Ruth Sloan Professor of Political Science, has been named director of the MIT Security Studies Program (SSP). Barry Posen, Ford International Professor of Political Science and director of SSP since 2006, announced the leadership transition to the SSP community at its recent gala dinner.

Fravel takes over as director today. Posen will continue his research and teaching responsibilities at MIT. As a member of SSP, he will continue leading the Grand Strategy, Security, and Statecraft Fellows Program.

"SSP is a community of scholars dedicated to the proposition that the problem of international and internal war merits sustained study. I have every confidence that Taylor will bring an infusion of new ideas, and energy to attempt new initiatives, that come with a new leader," says Posen. 

SSP is widely recognized as a leader in its field, generating research on international security issues and training graduate students for careers in academia, government, business, and civil society organizations. The MIT Center for International Studies (CIS) provides the intellectual home and the administrative infrastructure for SSP.

Fravel is an expert on international security, with a focus on China's foreign and security policies. He joined MIT in 2004 as assistant professor of political science and member of SSP. He currently serves on the editorial boards of Security Studies, Journal of Strategic Studies, and the China Quarterly, and is a member of the board of directors for the National Committee on United States-China Relations. 

Fravel's most recent book, "Active Defense: China's Military Strategy Since 1949," was published by Princeton University Press earlier this year. It has been praised as "the first book to provide a comprehensive history of China's military doctrine as it has evolved since the founding of the People's Republic." 

"SSP is one of the country's preeminent university-based programs for the study of international security," Fravel says. "For more than 40 years, the faculty, fellows, and students of SSP have been conducting policy-relevant and rigorous research on questions of war and peace, both among states and within them. I am honored to be given this opportunity to serve as director and look forward to working with my SSP and MIT colleagues in this new role."

Fravel is a graduate of Middlebury College and Stanford University, where he received his PhD in political science. He has been a postdoc at the Olin Institute for Strategic Studies at Harvard University, a predoctoral fellow at the Center for International Security and Cooperation at Stanford University, a fellow with the Princeton-Harvard China and the World Program, and a visiting scholar at the American Academy of Arts and Sciences. He also has graduate degrees from the London School of Economics and Oxford University, where he was a Rhodes scholar.