Exact quantum-mechanical, Pad´e-based recovery of spectral parameters - Signal Processing in MRS with Biomedical Applications - page 115

CONSECUTIVE DIFFERENCE SPECTRA in FPT (+) (Left) and FPT (−) (Right) ; FID LENGTH: N P = 140, 180, 220, 260

Subtraction of 2 Spectra; FID Length: 180, 140 Subtraction of 2 Spectra; FID Length: 180, 140

12 12

8 8

N P = 140 and 180 B 0 =1.5T N P = 140 and 180 B 0 =1.5T

4 4

0 0

−4 −4

FPT (+) (180) − FPT (+) (140) FPT (−) (180) − FPT (−) (140) −8 −8

−12 −12

5 4 3 2 1 5 4 3 2 1

(i) Chemical shift (ppm) (iv) Chemical shift (ppm)

Subtraction of 2 Spectra; FID Length: 220, 180 Subtraction of 2 Spectra; FID Length: 220, 180

12 12

8 8

N P = 180 and 220 B 0 =1.5T N P = 180 and 220 B 0 =1.5T

4 4

0 0

−4 −4

FPT (+) (220) − FPT (+) (180) FPT (−) (220) − FPT (−) (180) −8 −8

−12 −12

5 4 3 2 1 5 4 3 2 1

(ii) Chemical shift (ppm) (v) Chemical shift (ppm)

Subtraction of 2 Spectra; FID Length: 260, 220 Subtraction of 2 Spectra; FID Length: 260, 220

12 12

8 8

N P = 220 and 260 B 0 =1.5T N P = 220 and 260 B 0 =1.5T

4 4

0 0

−4 −4

FPT (+) (260) − FPT (+) (220) FPT (−) (260) − FPT (−) (220) −8 −8

−12 −12

5 4 3 2 1 5 4 3 2 1

(iii) Chemical shift (ppm) (vi) Chemical shift (ppm)

FIGURE 3.9
Consecutive difference spectra for absorption total shape spectra in the
FPT (+) (left) and FPT (−) (right) near full convergence for the adjacent signal
lengths N P = 140, 180, 220, 260.