Motor vehicles

The Research Brief is a short take about interesting academic work. The big idea A new plant-based substitute for polyurethane foam eliminates the health risk of the material, commonly found in insulation, car seats and other types of cushioning, and it’s more environmentally sustainable, our new research shows. Polyurethane foams are all around you, anywhere a lightweight material is needed for cushioning or structural support. But they’re typically made using chemicals that are suspected carcinogens. Polyurethanes are typically produced in a very fast reaction between two chemicals made by the petrochemical industry: polyols and isocyanates. While much work has gone into finding replacements for the polyol component of polyurethane foams, the isocyanate component has largely remained, despite its consequences for human health. Bio-based foams can avoid that component. These bio-based foams avoid the need for petroleum pro...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com. Why do we use gasoline for small vehicles and diesel fuel for big vehicles? – Methdini, age 15, Sri Lanka Gasoline fuels most light-duty vehicles, such as passenger cars and pickup trucks. Heavy-duty vehicles, like buses, delivery trucks and long-haul tractor-trailers, typically run on diesel. Both fuel types are needed because gasoline and diesel engines have different strengths. As my automotive engineering students learn, this makes them suitable for different uses. Let’s start with what they have in common. Gas and diesel engines both work through a process called internal combustion. First, they mix fuel with air because the fuel needs oxygen from the air to burn. Next, they compress the fuel-air mixture, which ma...