Development and applications of pulses sequences with alternating phases in the time domain NMR .

• Grant number: 13/03770-1
• Support type: Scholarships in Brazil - Master
• Effective date (Start): August 01, 2013
• Effective date (End): July 31, 2015
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal researcher: Luiz Alberto Colnago
• Grantee: Tatiana Monaretto
• Home Institution: Embrapa Instrumentação Agropecuária. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA). Ministério da Agricultura, Pecuária e Abastecimento (Brasil). São Carlos , SP, Brazil

Abstract

Time domain NMR spectroscopy (TD-NMR) has shown great potential in nondestructive analysis of fresh and processed foods. The great advantage of TD-NMR, when compared with other NMR techniques, is a lower cost equipment, high speed and does not require specialized operators. In this type of apparatus, the chemical shift is not observed and measurements are performed in the time domain. TD-NMR Measurements are based on differences in longitudinal relaxation time, T1, and transversal T2, the various components of the samples. Therefore, we have been developing pulse sequences, as CWFP and CP-CWFP, to measure simultaneously the two relaxation times. However, these methods need a precise adjusted of frequency offset. Therefore, the objective of this project is to improve these sequences with the introduction of alternating phase between pulses. With this technique it is not necessary to adjust the frequency offset, which makes the method more robust and more accurate.Moreover, these sequences will also been used to flow analysis using a medium resolution spectrometer (1 ppm)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MORAES, TIAGO BUENO; MONARETTO, TATIANA; COLNAGO, LUIZ ALBERTO. Applications of Continuous Wave Free Precession Sequences in Low-Field, Time-Domain NMR. APPLIED SCIENCES-BASEL, v. 9, n. 7 APR 1 2019. Web of Science Citations: 0.

POLIANA M. SANTOS; FLÁVIO VINICIUS C. KOCK; MAIARA S. SANTOS; CARLOS MANUEL S. LOBO; ANDRÉ S. CARVALHO; LUIZ ALBERTO COLNAGO. Non-Invasive Detection of Adulterated Olive Oil in Full Bottles Using Time-Domain NMR Relaxometry. Journal of the Brazilian Chemical Society, v. 28, n. 2, p. 385-390, Fev. 2017. Web of Science Citations: 6.

MORAES, TIAGO BUENO; MONARETTO, TATIANA; COLNAGO, LUIZ ALBERTO. Rapid and simple determination of T-1 relaxation times in time-domain NMR by Continuous Wave Free Precession sequence. JOURNAL OF MAGNETIC RESONANCE, v. 270, p. 1-6, SEP 2016. Web of Science Citations: 7.

MONARETTO, TATIANA; ANDRADE, FABIANA DIUK; MORAES, TIAGO BUENO; SOUZA, ANDRE ALVES; DEAZEVEDO, EDUARDO RIBEIRO; COLNAGO, LUIZ ALBERTO. On resonance phase alternated CWFP sequences for rapid and simultaneous measurement of relaxation times. JOURNAL OF MAGNETIC RESONANCE, v. 259, p. 174-178, OCT 2015. Web of Science Citations: 6.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

. Development and Applications of CWFP Pulses Sequences with Phase Alternation in Time Domain NMR. 2015. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC/BT) São Carlos.