| Texto completo | |
| Autor(es): |
Monaretto, Tatiana
;
Montrazi, Elton Tadeu
;
Moraes, Tiago Bueno
;
Souza, Andre Alves
;
Rondeau-Mouro, Corinne
;
Colnago, Luiz Alberto
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF MAGNETIC RESONANCE; v. 311, p. 7-pg., 2020-02-01. |
| Resumo | |
The transverse relaxation time (T-2), measured with Carr-Purcell-Meiboom-Gill (CPMG) sequence, has been widely used to obtain the direct dimension data in two-dimension time domain NMR (2D TD-NMR). In this paper we are demonstrating that Continuous Wave Free Precession sequence, with low flip angle (CWFP-T-1), can be an alternative to CPMG as direct detection dimension. CWFP-T-1 is a fast single shot sequence, like CPMG, and yields an exponential signal governed predominantly by the longitudinal (T-1) relaxation time. To obtain the correlations between T-1 and T-2 (T-1 -T-2 maps) we are proposing the use of CPMG-CWFP-T-1 pulse sequence. In this sequence CPMG encodes T-2 information (indirect dimension) that modulates the CWFP-T-1 (direct dimension) signal amplitudes. CPMG-CWFP-T-1 experiments were compared with classical 2D sequences such as Saturation-Recovery-CPMG (SR-CPMG) and InversionRecovery-CPMG (IR-CPMG) sequence and yields similar results in phantom sample. The experimental time for the 2D sequences, using single scan, shows that SR-CPMG <= CPMG-CWFP-T-1 < IR-CPMG. Experimental and simulated results demonstrated that 2D-CPMG-CWFP-T-1 maps have higher resolution in T-1 dimension than the techniques that uses CPMG as direct dimension. CPMG-CWFP-T-1 sequence was also applied to study beef samples, and 2D maps showed higher resolution in the two fat signals than the classical IR-CPMG method. (C) 2019 Elsevier Inc. All rights reserved. (AU) | |
| Processo FAPESP: | 19/13656-8 - Desenvolvimento e aplicações da ressonância magnética nuclear em produtos e processos de interesse agropecuário |
| Beneficiário: | Luiz Alberto Colnago |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 17/12864-0 - Avaliação do efeito do campo magnético dos espectrômetro de RMN em reações químicas monitoradas in situ |
| Beneficiário: | Luiz Alberto Colnago |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |