Each atom of a particular element will have the same number of protons in its core. (sciencenewsforstudents.org)
Researchers there smashed together beams of protons with beams of lead ions, producing showers of subatomic particles that flew away in all directions at high speed. (newscientist.com)
The [society] will discuss the mass of a proton for example, or negative energy, but global warming is incontrovertible.... (dotearth.blogs.nytimes.com)