EDS spectra of control and nanoparticle samples Left, EDS spectrum of a control region with no nanoparticles. Chemical components include C, Cu, and small amounts of O and Si. Both Cu and C are from the grid and grid coating respectively. Right, EDS spectrum of a nanoparticle. Chemical components include Ca, Mg, O, and Cl. The presence of high amounts of Ca, Mg, and Cl, along with the crystalline structure of the nanoparticles indicates that the nanoparticles are the results of salts in the adhesive.