More than 90 percent of the world’s energy use today involves heat, whether for producing electricity, heating and cooling buildings and vehicles, manufacturing steel and cement, or other industrial activities. Collectively, these processes emit a staggering amount of greenhouse gases into the environment each year. Reinventing the way we transport, store, convert, and use thermal energy would go a long way toward avoiding a global rise in temperature of more than 2 degrees Celsius — a critical increase that is predicted to tip the planet into a cascade of catastrophic climate scenarios. But, as three thermal energy experts write in a letter published today in Nature Energy, “Even though this critical need exists, there is a significant disconnect between current research in thermal sciences and what is needed for deep decarbonization.” In an effort to motivate the scientific community to work on climate-critical thermal issues, the authors have laid out five thermal energy “grand challenges,” or broad areas where significant innovations need to be made in order to stem the rise of global warming. MIT News spoke with Asegun Henry, the lead author and the Robert N. Noyce Career Development Associate Professor in the Department of Mechanical Engineering, about this grand vision....

Thermosets, which include epoxies, polyurethanes, and rubber used for tires, are found in many products that have to be durable and heat-resistant, such as cars or electrical appliances. One drawback to these materials is that they typically cannot be easily recycled or broken down after use, because the chemical bonds holding them together are stronger than those found in other materials such as thermoplastics. MIT chemists have now developed a way to modify thermoset plastics with a chemical linker that makes the materials much easier to break down, but still allows them to retain the mechanical strength that makes them so useful. In a study appearing today in Nature, the researchers showed that they could produce a degradable version of a thermoset plastic called pDCPD, break it down into a powder, and use the powder to create more pDCPD. They also proposed a theoretical model suggesting that their approach could be applicable to a wide range of plastics and other polymers, such as rubber....

MIT and Harvard University chemists have discovered the structure of an unusual bacterial enzyme that can break down an amino acid found in collagen, which is the most abundant protein in the human body. The enzyme, known as hydroxy-L-proline dehydratase (HypD), has been found in a few hundred species of bacteria that live in the human gut, including Clostridioides difficile. The enzyme performs a novel chemical reaction that dismantles hydroxy-L-proline, the molecule that gives collagen its tough, triple-helix structure. Now that researchers know the structure of the enzyme, they can try to develop drugs that inhibit it. Such a drug could be useful in treating C. difficile infections, which are resistant to many existing antibiotics. “This is very exciting because this enzyme doesn’t exist in humans, so it could be a potential target,” says Catherine Drennan, an MIT professor of chemistry and biology and a Howard Hughes Medical Institute Investigator. “If you could potentially inhibit that enzyme, that could be a unique antibiotic.”...

MIT researchers have discovered a phenomenon that could be harnessed to control the movement of tiny particles floating in suspension. This approach, which requires simply applying an external electric field, may ultimately lead to new ways of performing certain industrial or medical processes that require separation of tiny suspended materials. The findings are based on an electrokinetic version of the phenomenon that gives curveballs their curve, known as the Magnus effect. Zachary Sherman PhD ’19, who is now a postdoc at the University of Texas at Austin, and MIT professor of chemical engineering James Swan describe the new phenomenon in a paper published this week in the journal Physical Review Letters. The Magnus effect causes a spinning object to be pulled in a direction perpendicular to its motion, as in the curveball; it is based on aerodynamic forces and operates at macroscopic scales — i.e. on easily visible objects — but not on smaller particles. The new phenomenon, induced by an electric field, can propel particles down to nanometer scales, moving them along in a controlled direction without any contact or moving parts....