Lacking study motivation? These epic film scores are sure to make even rote memorization feel like a superhero mission.
The scientist whose discovery stops speeding bullets was inducted into the National Women’s Hall of Fame in Seneca Falls, N.Y., on Oct. 4, 2003. Stephanie L. Kwolek, a retired research chemist from DuPont, was honored for research that led to the development of Kevlar, an aramid fiber five times stronger than steel. DuPont credits bullet- and knife-resistant body armor made of Kevlar with saving the lives of nearly 3,000 law enforcement officers.
Kwolek, 80, started work for DuPont in 1946 as a laboratory chemist in Buffalo, N.Y. She planned to stay with the company just long enough to save up for medical school. But the freedom and creativity she experienced in the DuPont environment led her to stay with the company for 40 years.
A Hall of Fame Selects Kevlar Inventor
3D Printing: Make anything you want
Researchers from Empa (Swiss Federal Laboratories of Materials Science & Technology) have developed a chemically modified nanocellulose sponge that could help clean up oil spills. Shown here, a droplet of water (blue) sits on the surface, whereas a droplet of oil (red) is absorbed by the material. In the lab, test substances such as engine oil, silicone oil, ethanol, acetone, and chloroform were absorbed within seconds. The absorbent can be produced in an environmentally friendly manner from recycled paper, wood, or agricultural by-products.
Good question! Flames arise from the combustion of a fuel in oxygen. The flames themselves are a mixture of reacting gases and solids produced by this reaction. The exact chemical composition will depend on what is being burned - however, they’ll often include a range of compounds containing carbon, hydrogen, and oxygen.
The products in the flame, produced by the combustion reaction, are at such a high temperature in the flame that they exhibit incandescence. This is simply the emission of light. Different chemicals give out different coloured lights, as illustrated by the fact that different metal ions can produce different flame colours. Soot (carbon-based compounds) particles are responsible for the characteristic red/orange glow of fire.
Everything is capable of exhibiting incandescence- almost all solids will glow with a dull red colour around 525 degrees celsius. Sunlight is in fact the incandescence of the white hot surface of the sun.
Although it’s often stated that fire is a plasma, unless it is at a very high temperature, it’s actually just incandescent gas.
References & Further Reading