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The facile method to functionalize graphene oxide through surface modification with acetone was studied and improved. The resulting nanomaterials showed variable characteristics as the surface energy could be tailored according to the combination (proportion of H2O to acetone) of mixed solvent under sonication. Stability test and contact angle measurement showed that the treated graphene oxide exhibited different dispersibility and wettability. SEM images of graphene oxide films corroborated the changes in chemical composition of the sheets. FT-IR, XPS, and TGA observation provided direct evidence for chemical composition changes occurred on the surface. The presence of alkyl chain could decrease the surface energy and obviously control the hydrophilicity of the graphene oxide sheets. These results will provide significant guidance for the study of graphene-based bio-materials and nano-composites. [ABSTRACT FROM AUTHOR]

l-cystine and l-cysteine have been intercalated into magnesium–aluminum layered double hydroxide by the methods of coprecipitation and ion-exchange. The structure and composition of the intercalated materials have been characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and elemental analysis. For l-cysteine intercalated composites, two kinds of well-crystallized materials with different basal spacing were obtained, as a result of the different charge on an ion and orientation of the gallery anions. The schematic models of the intercalation structures were proposed. In addition, the thermal decomposition of l-cystine and l-cysteine intercalated LDHs has been investigated by means of thermogravimetry and differential thermal analysis (TG-DTA). [ABSTRACT FROM AUTHOR]

The effects of a high magnetic field on the interdiffusion behavior at liquid Bi/solid Bi0.4Sb0.6 interface have been experimentally investigated. It was found that the migration of the interface due to interdiffusion decreased markedly with the increasing strength of magnetic field. This was relevant to the increasing of the viscosity in the liquid metal under a high magnetic field, which in turn caused diffusion activation energy to increase. As a consequence, in the presence of a high magnetic field, a considerable decrease in the effective diffusion coefficient occurred. Moreover, the retarding effect of magnetic field gradient on diffusion was found to be more significant than that of a uniform magnetic field. [ABSTRACT FROM AUTHOR]