What positively charged particle is located at the center of the atom in the nucleus?

The positively charged particle located at the center of an atom is the proton.

Think p in proton and positive.  Neutrons are also located in the nucleus of an atom, but they have a neutral charge (neutron and neutral).

Hope this helps!!

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: