• 한국전기화학회:학술대회논문집
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• 2005.07a
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• pp.83-86
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• 2005

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.4
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• pp.439-445
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• 2007

Proton exchange membrane Fuel Cells(PEMFCs) have been spotlighted because of their broad potential application for potable electrical devices, automobiles and residential usages. However, their utilization is limited to low temperature operation due to the electrolyte dehydration at high temperature. High temperature PEMFC operation offers high CO tolerance and easy water management. This review presents development of high temperature($120{\sim}200^{\circ}C$) PEMFC. Especially, PEMFC which is based on acid-doped PBI membrane is discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1799-1805
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• 2015

Rice vinegar (RV) is primarily made from fermented rice or rice wine in Korea, China, and Japan. Ten commercially available naturally-fermented rice vinegars produced in Korea (KRV1~4), China (CRV1~2), and Japan (JRV1~4) were comparatively investigated for their physicochemical properties and antioxidant activities. KRV showed a significantly higher total acidity range (5.07~6.27) than both CRV (4.67~4.84) and JRV (4.64~4.84). These acidity ranges corresponded with respective standards of each country: Korea (Food Code), China (GB), and Japan (JAS). Six different organic acids were detected in RVs; acetic acid and succinic acid were the most prominent. Thirty different amino acids were detected in RVs, and main identified amino acids were alanine (KRV), phenylalanine and aspartic acid (CRV), and leucine and alanine (JRV). ${\gamma}-Aminobutyric$ acid was detected at high concentration in KRV1. KRV1 showed maximum total phenolic content, and DPPH and ABTS radical scavenging activities of samples were also determined with significantly increasing tendency. KRV1 (produced from brown rice with aging period of >1 year) exhibited the highest free amino acid content and antioxidant activity as compared to CRV and JRV.

• Food Science and Preservation
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• v.22 no.5
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• pp.629-635
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• 2015

The effect of temperature on the quality and characteristics of Valencia oranges were studied during storage at low ($4^{\circ}C$, LT) and room ($20^{\circ}C$, RT) temperature. Hardness decreased beginning on the 10th day of storage, regardless of temperature, and showed a more considerable reduction in the peel than the flesh. The total soluble solids (TSS) and titratable acidity (TA) decreased from the 30th day at LT and the 10th day at RT, but the TSS/TA ratio did not change during storage. The vitamin C content decreased from the 20th day at LT and the 10th day at RT, and the total phenol content decreased from the 10th day of storage. In a sensory evaluation, the scores changed less for taste than for color and flavor during storage. The quality of Valencia oranges under two different temperatures was similar on the 30th day at LT and on the 10th day at RT. The TSS (r = 0.9453) and vitamin C content (r = 0.9104) were highly related to sensory properties. These results suggested that TSS and vitamin C are potential indicators of quality for the selection of Valencia oranges during storage.