Utilize este identificador para referenciar este registo:
https://hdl.handle.net/10316/21202
Título: | Homogeneous length scale of shear-induced multilamellar vesicles studied by diffusion NMR | Autor: | Åslund, Ingrid Medronho, Bruno Topgaard, Daniel Söderman, Olle Schmidt, Claudia |
Palavras-chave: | Diffusion; Pulsed-gradient-spin-echo NMR; Lamellar phase; Shear | Data: | Abr-2011 | Editora: | Elsevier | Citação: | ÅSLUND, Ingrid [et al.] - Homogeneous length scale of shear-induced multilamellar vesicles studied by diffusion NMR. "Journal of Magnetic Resonance". ISSN 1090-7807. 209:2 (2011) 291-299 | Título da revista, periódico, livro ou evento: | Journal of Magnetic Resonance | Volume: | 209 | Número: | 2 | Resumo: | A recently developed protocol for pulsed gradient spin echo (PGSE) NMR is applied for the size determination of multilamellar vesicles (MLVs). By monitoring the self-diffusion behavior of water, the technique yields an estimate of the homogeneous length scale λhom, i.e. the maximum length scale at which there is local structural heterogeneity in a globally homogeneous material. A cross-over between local non-Gaussian to global Gaussian diffusion is observed by varying the experimentally defined length- and time-scales. Occasional observation of a weak Bragg peak in the PGSE signal attenuation curves permits the direct estimation of the MLV radius in favorable cases, thus yielding the constant of proportionality between λhom and radius. The microstructural origin of the Bragg peak is verified through Brownian dynamics simulations and a theoretical analysis based on the center-of-mass diffusion propagator. λhom is decreasing with increasing shear rate in agreement with theoretical expectations and results from 2H NMR lineshape analysis. | URI: | https://hdl.handle.net/10316/21202 | ISSN: | 1090-7807 | DOI: | 10.1016/j.jmr.2011.01.024 | Direitos: | openAccess |
Aparece nas coleções: | FCTUC Química - Artigos em Revistas Internacionais |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
---|---|---|---|---|
Homogeneous length scale of shear-induced.pdf | 2.1 MB | Adobe PDF | Ver/Abrir |
Todos os registos no repositório estão protegidos por leis de copyright, com todos os direitos reservados.