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Abstract:The presence of N-phenyl-p-phenylenediamine (PPDA: a dimer of aniline) during microwave (MW) irradiation can significantly improve Pt-loading on the XC72 carbon matrix as a catalyst support of proton exchange membrane fuel cells (PEMFCs). PPDA is converted to an emeraldine base state during MW-assisted redox reaction, which is characterized by both FTIR and Raman spectra. The increased degree of conjugation from the formation of quinone-state of PPDA is confirmed by UV-VIS spectra. TEM micrographs and residue weights obtained from the TGA thermograms illustrate the particle size and Pt-loading percent of Pt nanoparticles (NPs) after MW irradiation, respectively. X-ray diffraction patterns indicate Pt NPs are successfully loaded on XC72 by MW irradiation corresponding to hydrothermal method. The single cell performance demonstrates an increasing power and maximum current density when Pt-catalyst of membrane exchanged assembly (MEA) is prepared by MW-assisted reduction in the presence of PPDA.

The topography and frictional force of Asian black male and female hair cuticles at different locations are determined using atomic force microscopy (AFM) and friction force microscopy (FFM). The frictional values, mapped for comparison with surface morphology, corresponded qualitatively with the structures’ plane surface characteristics. The results indicate that the hair surface was damaged and modified at different temperatures and heating times. The height of the female hair at a blowing temperature of 60°C after a duration of 2 min between the cuticle edge and cuticle surface was approximately 440–556 nm. The adhesion phenomenon occurs on the hair surface and interface. The cuticles do not vary after the heating; however, the hair damage sustained increases with serious deterioration.

DNA biopolymer has emerging as a promising material in photonic applications. In this paper, we present the preparation and characterization of a series of DNA-surfactant complexes based on aromatic surfactants, including vinylbenzyltrimethylammonium chloride, benzyltrimethylammonium chloride, and phenyltrimethylammonium chloride. Fourier-transform infrared spectroscopy (FTIR) and UV-VIS spectroscopy were used to characterize the presence of specific chemical groups in the materials. These synthesized DNA complexes show high transparency from 400nm to 1100nm. These materials can be spin casted into thin films from nm to um and the morphology was examined by SEM and AFM. Thermal property was characterized by thermogravimetric analysis. Conductivity was examined to investigate the effect of aromatic surfactants on the electrical properties of DNA complexes. In addition, the photoluminescence and lasing properties for DNA-aromatic surfactants with rhodamine dyes were investigated to study the amplified spontaneous emission where the ASE emission wavelength, lasing threshold, and gain were presented and discussed. The results were compared with DNA complex with single chain aliphatic surfactant complex (DNAcetyltrimethylammoniumchloride).