Data/hora: 14/06/2024 07:04:44

Biblioteca(s): | Embrapa Solos.
Data corrente: | 07/02/2022
Data da última atualização: | 24/03/2022
Autoria: | TEAL, P. D.; NOVOTNY, E. H.
Afiliação: | PAUL D. TEAL, VICTORIA UNIVERSITY OF WELLINGTON; ETELVINO HENRIQUE NOVOTNY, CNPS.
Título: | Improved data efficiency for NMR diffusion-relaxation processing.
Ano de publicação: | 2022
Fonte/Imprenta: | Journal of Magnetic Resonance, v. 335, 107124, Feb. 2022.
DOI: | https://doi.org/10.1016/j.jmr.2021.107124
Idioma: | Inglês
Conteúdo: | Two dimensional diffusion and transverse () NMR relaxation measurements are effective for a variety of research and industrial processes. Conversion of the measurements into a D- map is performed using an inverse integral transformation. A difficulty with D- estimation from data acquired without pulsed field gradients (using, for example, the inherent static field gradient of a single-sided magnet) is that the diffusion and relaxation kernels are coupled. One commonly used solution is to introduce a time offset to enable the kernels to be decoupled, but this has the undesirable results of causing some of the data, and a large proportion of the signal energy, to become unusable. This paper presents two methods of processing the data that do not require this wastage. Both methods are based on insights that arise from considering the linear operator that describes the forwards integral transformation. One method involves data compression, while the other method is an application (that we call FLINT) of the fast iterative soft thresholding algorithm. Both methods are able to use all of the available data. The paper demonstrates the improved accuracy that results from these methods on simulated data, as well as the improved discovery of important features on measured data.
Palavras-Chave: | BRD; Diffusion-edited CPMG; Diffusion-relaxation distribution; FLINT; Inversion; Static gradient.
Thesaurus Nal: | Estimation.
Categoria do assunto: | P Recursos Naturais, Ciências Ambientais e da Terra
Registro original: | Embrapa Solos (CNPS)
Exemplares: | CNPS - (20970-1) - UPC - AP - DD -  -  -  - DIS