Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
J Phys Chem B ; 112(23): 7045-50, 2008 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-18476734

RESUMO

Monte Carlo simulations of the diamagnetic orientation of a fluid of hard thin disks in a magnetic field are presented. The particle density and magnetic field dependences of the eigenvalues of the order parameter tensor are calculated in the presence of a wall which promotes nematic order in a definite direction. The existence of a paranematic region is confirmed, and the approach to the Langevin regime at low densities in the paranematic regime is examined. A relationship between the eigenvalues of the tensor and the anisotropy of water diffusivity in the nematic phase of a colloidal suspension is proposed. This permits a comparison between the Monte Carlo simulations and diffusion-weighted magnetic resonance imaging, which shows consistency with the experimental data.

2.
Langmuir ; 23(9): 5100-5, 2007 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-17375942

RESUMO

Diffusion-weighted magnetic resonance imaging provides a vivid description of the little understood role played by interfacial interactions with macroscopic bodies in the cooperative self-assembly of clay nanoplatelets suspended in water. The interfacial interaction between hydrophilic glass walls and clay platelets in a Na-fluorhectorite gel can produce, for dilute gels, a face-to-wall anchoring of the platelets that leads to a uniaxial nematic order with platelet faces parallel to the walls but with randomly distributed normals of the faces. The application of a magnetic field perpendicular to the walls transforms this uniaxial order to an extended biaxial nematic order with orthogonal alignment between normals and the field. Moreover, for apolar walls, this face-to-wall anchoring is considerably hindered, and the uniaxial nematic order can be substantially disrupted.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA