Experimental Procedure to Optimize the Performance of PISEMA

The test system used for simulations included directly bonded and nuclei with the N-H bond length of 1.07 A, and two remote protons that are weakly coupled to the N-bonded proton with dipolar couplings of 4 and 5 kHz at different orientations. The powder patterns of dipolar coupling were then simulated to evaluate 

Efficiency of spin-locks. Examine the efficiency of Zj spin-locks on / and S rf channels using pulse sequences discussed elsewhere. The longest time for which the magnetization can be spin-locked on both channels depends on the strength of the rf power, stability of rf amplifiers, rf field inhomogeneity, effects of phase transients, span of the chemical shift, T p of the nuclei (assuming no spin-lock on the other channel), and the quality of the probe. In addition, on the /-spin channel, it also depends on the degree of suppression of the / / dipolar 

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