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We developed a single step thermal method to synthesize platinum nanoparticle functionalized graphene sheets (Pt-G) through the thermal treatment of graphite oxide (GO) with platinum acetylacetonate (Pt(acac) 2 ). The loading concentration of platinum nanoparticles (Pt NPs) on graphene is about 22.3 wt%. We investigate the Pt NP functionalization and the reduction effects of GO by scanning electron microscopy, transmission electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis and Raman spectroscopy. The results lead to insights into the formation of Pt-G starting from GO upon increasing the temperature. XPS and XRD analysis confirm that the platinum nanoparticle deposition is accompanied by the reduction and exfoliation of GO. Electrochemical studies reveal that Pt-G shows excellent activity and stability towards the methanol oxidation reaction.

This study investigated the effect of various freezing and thawing techniques on the quality of beef. Meat samples were frozen using natural convection freezing (NF), individual quick freezing (IQF), or cryogenic freezing (CF) techniques, followed by natural convection thawing (NCT) or running water thawing (RT). The meat was frozen until the core temperature reached -12℃ and then stored at -24℃, followed by thawing until the temperature reached 5℃. Quality parameters, such as the pH, water binding properties, CIE color, shear force, and microstructure of the beef were elucidated. Although the freezing and thawing combinations did not cause remarkable changes in the quality parameters, rapid freezing, in the order of CF, IQF, and NF, was found to minimize the quality deterioration. In the case of thawing methods, NCT was better than RT and the meat quality was influence on the thawing temperature rather than the thawing rate. Although the microstructure of the frozen beef exhibited an excessive loss of integrity after the freezing and thawing, it did not cause any remarkable change in the beef quality. Taken together, these results demonstrate that CF and NCT form the best combination for beef processing; however, IQF and NCT may have practical applications in the frozen food industry.

Self-assembly of 1D nanoparticles such as carbon nanotubes or nanorods into highly ordered superstructures using various interactions has been of great interest as a route toward materials with new functionalities. However, the phase behavior of 1D nanoparticles interacting with surrounding materials, which is the key information to design self-assembled superstructures, has not been fully exploited yet. Here, we report for the first time a new phase diagram of negatively charged 1D nanoparticle and cationic liposome (CLs) complexes in water that exhibit three different highly ordered phases, intercalated lamellar, doubly intercalated lamellar, and centered rectangular phases, depending on particle curvature and electrostatic interactions. The new phase diagram can be used to understand and design new highly ordered self-assemblies of 1D nanoparticles in soft matter, which provide new functionalities.