The effects of metals such as cobalt (Co). cerium (Ce). magnesium (Mg). nickel (Ni) and titanium (Ti) added to diamond-like carbon (DLC) films on boundary lubrication properties were investigated using a ball-on disk tribometer. https://www.diegojavierfares.com/limited-stock-Game-of-Thrones-Jon-Snow-Poster-great-offer/