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a. F2 dimension (15N) should be REVERSE. but only for HNCO not for HNCA b. This pulse sequence works better than other hnco's based on 1D optimization. c. For 3D sequences, States_TTPI works better than EA. There are no issues with T1 noise and S/N is better. d. For 2D sequences, States_TTPI has worse T1 noise.
The experiments were performed with a precipitated fractionally deuterated U-13C/15N KcsA, LPR =1, 9:1 DOPE-DOPS D2O citrate buffer pH 3.5