Shielded Protons electrons shielding effective effective field field 70.458 70.459 300 MHz 300MH 300MH absorbs does not absorbs absorb Bo Bo Bo 70.459 gauss 70,459 gauss 70,460 gauss naked proton shielded proton stronger applied field absorbs at 70.459 G feels less than 70,459 G compensates for shielding Copyright 2010 Pearson Prentice Hall.Inc. A naked proton will absorb at 70,459 gauss. A shielded proton will not absorb at 70,459 gauss so the magnetic field must be increased slightly to achieve resonance. Chapter 13 10Chapter 13 10 Shielded Protons • A naked proton will absorb at 70,459 gauss. • A shielded proton will not absorb at 70, 459 gauss so the magnetic field must be increased slightly to achieve resonance