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"The aim of this study was to synthesize high luminescence materials containing the optimal combination of ternary europiumpicrate complex and matrices. The ternary europium-picrate-triethylene glycol (Eu-EO3-Pic) complex was doped in poly(methyl methacrylate), PMMA. The composites were impregnated in several matrices to form thin filmsvia spin coating technique. The microparticles of Eu-EO3-Piccomplex were prepared by reprecipitation-evaporation, then they were compared to analogous complex or microcomposite prepared by in-situ method. The Eu-EO3-Pic/PMMA microcomposites were characterized by fluorescence spectroscopy in acetone solution. The particle sizes distribution of microcomposites synthesized by reprecipitation-evaporation method (110.3 to 426.8 nm) were smaller compared to the microcomposites by in-situ method (641.7 nm). The PMMA was able to significantly enhance the fluorescence intensity of Eu-EO3-Pic microparticles. The fluorescence intensity of microcomposite by in situ-preparation was lower than that found in the microcomposites by reprecipitation-evaporation method. We also investigated the effect of different matrices on the photophysical properties. The effective intermolecular energy transfer from PMMA to the Eu-EO3-Pic complex would produce high sensitization efficiency. These microcomposites are very potential used as the emission material for organic light emitting devices."

"Microstructural identification of synthesized steel with significant local content has been carried out. Alloy ingot was prepared using a casting technique. The samples were then formed into bulk steel by a machining process. A high resolution powder neutron diffractometer (HRPD) was used as an equipment for characterization. By applying neutron diffraction techniques, a ferritic steel profile can be resulted in as well as ‘minor peaks’ belong to impurities formed in the sample. These impurities can be identified as small amounts of Al2O3 54SiO2, Al4C3, SiC and Cr23C6. Scanning transmission electron microscopy (STEM) combined with energy dispersive X-ray spectroscopy (EDX) confirmed and revealed neutron identified phase distributions. Joint Committee on Powder Diffraction Standards (JCPDS) least square curves calibration can precisely calculate the dhkl parameters of each reflection plane. As a comparison, another sample of alloy ingot was also investigated using neutron diffraction. The pattern was free from crystal impurities. Rietveld refinements provide satisfactory goodness of fits Rwp = 10.42% and reliability factor S = 1.7. This was so-called a ‘real bulky’ sample of a 73Fe24Cr2Si0.8Mn0.1Ni ferritic steel alloy."

"Solid sorbents based on graphite electrode waste and cerium oxide (ceria, CeO2) have been studied with regard to CO2 capture. The acid-base properties of cerium oxide produce a sorbent for the capture of CO2. The aim of the study is to evaluate the performance of CO2 capture using graphite/CeO2 composites at different weights of Ce(NO3)3.6H2O (0.5, 1 and 2 g), namely G0.5, G1 and G2, respectively. Volumetric adsorption studies of CO2 on graphite/CeO2 composites and ceria were conducted at various pressures (P) of 3, 5, 8, 15 and 20 bar, and temperatures (T) of 303, 308, 318 K. Graphite waste before modification (GBM), activated graphite waste (GA), and CeO2 for capturing CO2 were also investigated. By varying the two parameters (P and T), we found that the maximum adsorption capacities of CO2 at 303 K and 20 bar were 0.0713, 0.0316, 0.1574, 0.0987, 0.1137, and 0.0964 kg/kg respectively, for GBM, GA, G0.5, G1, G2 and CeO2. The highest adsorption capacity of CO2 was found in the G0.5 composite. The adsorption performance of CO2 using ceria was almost similar to the G1 composite. We found that CO2 adsorption capacity decreases with an increasing temperature from 303 to 318 K. It was concluded that ceria and composite graphite waste/CeO2 are stable and selective CO2 sorbents. The work allows us to synthesize a new sorbent which can be effectively applied for CO2 capture. The adsorption capacity of CO2 depends significantly on the active site and chemical modifier of the sorbents."