• Clean Technology
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• v.25 no.1
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• pp.81-90
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• 2019

A dielectric barrier discharge (DBD) plasma reactor packed with $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst was used for the dry ($CO_2$) reforming of propane (DRP) to improve the production of syngas (a mixture of $H_2$ and CO) and the catalyst stability. The plasma-catalytic DRP was carried out with either thermally or plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst at a $C_3H_8/CO_2$ ratio of 1/3 and a total feed gas flow rate of $300mL\;min^{-1}$. The catalytic activities associated with the DRP were evaluated in the range of $500{\sim}600^{\circ}C$. Following the calcination in ambient air, the ${\gamma}-Al_2O_3$ impregnated with the precursor solution ($Ni(NO_3)_2$ and $Ce(NO_3)_2$) was subjected to reduction in an $H_2/Ar$ atmosphere to prepare $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst. The characteristics of the catalysts were examined using X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectrometry (EDS), temperature programmed reduction ($H_2-TPR$), temperature programmed desorption ($H_2-TPD$, $CO_2-TPD$), temperature programmed oxidation (TPO), and Raman spectroscopy. The investigation revealed that the plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst exhibited superior catalytic activity for the production of syngas, compared to the thermally reduced catalyst. Besides, the plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst was found to show long-term catalytic stability with respect to coke resistance that is main concern regarding the DRP process.

• Korean Journal of Heritage: History & Science
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• v.57 no.3
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• pp.104-114
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• 2024

Sheet Music of the National Anthem of Korea with Lyrics in Korean, Chinese, and English is a four-sided sheet of paper folded in half. It was first introduced to Korea on November 12, 1945, by Kim Ku, the president of the Provisional Government. The sheet music was published in three languages and is a valuable document for researching the evolution of the anthem and its history. Although it was published in large quantities at the time, it is currently known as the only in Korea and has been designated and managed as a national registered heritage. The sheet music was not significantly damaged, but discoloration and physical damage suggested raised the need for conservation treatment. A pre-treatment examination of the conservation condition revealed that the artifact was received on archival film and had been folded in half for many years, leaving it vulnerable to tears at the top and bottom of the folds and partial wear and tear at the edges. In addition, the pigments used on both sides of the sheet had discolored and transferred to the opposite side. Portable X-ray fluorescence (XRF) analysis was conducted to investigate the pigments used in the sheet music cover, specifically focusing on red, black, and light blue pigments. Titanium (Ti) was detected in the light blue pigment, characterized by a powdery coloring layer. The remaining colors in the printed form were difficult to sample and could not be analyzed further. The light blue sample underwent additional analysis using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and Raman spectroscopy. Cross-validation of the results with the artifact's historical context suggested that the bright blue color observed in the 1945 sheet music is likely due to the use of anatase white pigment, rather than rutile. Furthermore, the bright blue pigment is believed to be a blend of phthalocyanine blue, a synthetic pigment introduced in 1936. Fiber analysis revealed longitudinal striations in the hemp fibers and twists in the cotton fibers, suggesting that the paper was made from a mixture of cotton and hemp fibers. Based on the findings of the condition survey, the conservation treatment for the artifact focused on minimizing moisture to avoid stressing the paper and reinforcing the physically vulnerable areas. The reinforcement paper was dyed to match the base of the artifacts, pre-coated repair paper was used for conservation, and appropriate folders and boxes were made for storage after treatment. This study is expected to serve as an important foundational resource on the materials used in modern and contemporary records.