Evaluation of alumina slurry dispersion by nuclear magnetic resonance relaxation as a comparison to conventional dispersion evaluation methods

In this paper, we evaluated the particle dispersion degree of alumina slurry containing a dispersant by solvent nuclear magnetic resonance (NMR) relaxation and compared it with conventional dispersion evaluation methods such as viscosity, particle size, and sedimentation height measurements. The dispersion of slurry was evaluated via numerical analysis of the transverse relaxation time (T₂). The effect of the changes in different parameters of the experiment in terms of milling time, solid loading, and dispersant amount was investigated by NMR relaxation as well as conventional methods. The results of NMR relaxation measurements revealed that T₂ correlates well with other dispersion evaluation methods; thus, it is an efficient technique to evaluate the dispersion of alumina slurry, specifically, when studying the effect of the change in milling time and dispersion amount.     

Microscopic functional specificity can be predicted from fMRI signals in ventral visual areas

Functional areas specialized for recognition can be activated by a non-preferred stimulus as well as a preferred stimulus. The functional magnetic resonance imaging signals detected in response to different stimuli in an area may have the same or different amplitudes. However, it is uncertain whether the responses originate from the same neuronal populations or heterogeneous ones. To address this concern, we propose a novel method that uses multi-echo echo-planar imaging sequences to evaluate changes in the transverse relaxation profile caused by stimulation. According to this method, the areas related with visual recognition, i.e. fusiform face area and parahippocampal place area, have different transverse relaxation profiles to preferred and non-preferred stimuli, which can be considered as reflecting a difference in neuronal population processing stimuli in those areas. The proposed method can be useful for probing the microscopic functional specificity of brain areas.     

Novel quantum description of time-dependent molecular interactions obeying a generalized non-central potential

Nonlinear Dynamics - Quantum features of time-dependent molecular interactions are investigated by introducing a time-varying Hamiltonian that involves a generalized non-central potential....