shell closure in a sentence

• It is also a useful method for probing the effects of shell closures on the survivability of compound nuclei in the super-heavy region, which can indicate the exact position of the next proton shell ( Z = 114, 120, 124, or 126 ).
• Other technical problems include finding off-shell closure of the constraint algebra and physical inner product vector space, coupling to matter fields of Quantum field theory, fate of the renormalization of the graviton in perturbation theory that lead to ultraviolet divergence beyond 2-loops ( see One-loop Feynman diagram in Feynman diagram ).
• It's difficult to see shell closure in a sentence .