While they usually go unnoticed until you lose one, tire valve caps do serve an important purpose. But are they universal, too? Here's what you need to know.

These valve stem caps are made in the U.S. from once-fired American-made 40 caliber rounds. Obviously they don't have any live primers, powder, or any explosives, so they're completely safe to use.

As a preliminary to establishing a frozen valve bank for replacement surgery, the possible effects of the proposed freezing and thawing procedure on tissue structure were assessed in 16 human ...

A unified CO2–amine reaction mechanism applicable to absorption in aqueous or nonaqueous solutions and to adsorption on immobilized amines in the presence of both dry and humid conditions is proposed.