http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Operating Conditions of Proton Exchange Membrane Fuel Cell Using Grafoil^{TM} as Bipolar Plates
박태현(Park, Taehyun),장익황(Chang, Ikwhang),이윤호(Lee, Yoon Ho),이주형(Lee, Juhyung),차석원(Cha, Suk-Won) 한국신재생에너지학회 2011 한국신재생에너지학회 학술대회논문집 Vol.2011 No.11
In this study, Grafoil^{TM} which has comparable electric resistance and chemical stability but is flexible, fragile, and cheap material was adopted as bipolar plates for proton exchange membrane fuel cell(PEMFC) having only one straight line flow channel. Because of its flexibility, pressurizations of cell with various pressures showed different operating characteristics compared to ordinary graphite-used PEMFC. While performances of both cells decreased as these were pressurized, investigation of ohmic and faradaic resistance by electrochemical impedance measurement indicated different tendency of change. Ohmic resistance of graphite-used cell increased with increasing pressure, which is reversed in Grafoil^{TM}-used cell. It is speculated that effective chemical reaction area is decreased with increasing pressure in case of graphite-used one, but because of flexible property of Grafoil^{TM}, gas diffusion layer in Grafoil^{TM}-used cell was well-activated. Different rate of change of faradaic resistances in both cells support this supposition. However, although optimum point of pressurization is found, it is required to investigate other operating conditions because of low performance compared to graphite-used cell.
Occurrence of Brown Blight Caused by Waitea circinata var. zeae on Cool Season Turfgrass in Korea
( Taehyun Chang ),( Yong Se Lee ) 한국균학회 2016 Mycobiology Vol.44 No.4
In 2010, disease symptoms, including necrotic lesions on stems and leaves with circular yellow-brown or irregular brown color patches, were observed on cool-season turfgrass at golf courses (OHCC) and the Daegu University research farm in Gyeongbuk, Korea. We isolated the causal agent and identified it as Waitea circinata var. zeae by morphological characterization and molecular analysis. To the best of our knowledge, this is the first report of brown patch caused by W. circinata var. zeae on cool-season turfgrass in Korea.
Evidence for Genetic Similarity of Vegetative Compatibility Groupings in Sclerotinia homoeocarpa
Chang, Seog Won,Jo, Young-Ki,Chang, Taehyun,Jung, Geunhwa The Korean Society of Plant Pathology 2014 Plant Pathology Journal Vol.30 No.4
Vegetative compatibility groups (VCGs) are determined for many fungi to test for the ability of fungal isolates to undergo heterokaryon formation. In several fungal plant pathogens, isolates belonging to a VCG have been shown to share significantly higher genetic similarity than those of different VCGs. In this study we sought to examine the relationship between VCG and genetic similarity of an important cool season turfgrass pathogen, Sclerotinia homoeocarpa. Twenty-two S. homoeocarpa isolates from the Midwest and Eastern US, which were previously characterized in several studies, were all evaluated for VCG using an improved nit mutant assay. These isolates were also genotyped using 19 microsatellites developed from partial genome sequence of S. homoeocarpa. Additionally, partial sequences of mitochondrial genes cytochrome oxidase II and mitochondrial small subunit (mtSSU) rRNA, and the atp6-rns intergenic spacer, were generated for isolates from each nit mutant VCG to determine if mitochondrial haplotypes differed among VCGs. Of the 22 isolates screened, 15 were amenable to the nit mutant VCG assay and were grouped into six VCGs. The 19 microsatellites gave 57 alleles for this set. Unweighted pair group methods with arithmetic mean (UPGMA) tree of binary microsatellite data were used to produce a dendrogram of the isolate genotypes based on microsatellite alleles, which showed high genetic similarity of nit mutant VCGs. Analysis of molecular variance of microsatellite data demonstrates that the current nit mutant VCGs explain the microsatellite genotypic variation among isolates better than the previous nit mutant VCGs or the conventionally determined VCGs. Mitochondrial sequences were identical among all isolates, suggesting that this marker type may not be informative for US populations of S. homoeocarpa.
Chang Ho Moon,Kang-Soo Han,Minwook Kim,Dong Kyo Oh,Sol Yi,Taehyun Kim,Hongkyu Kim,Jaehyun Hwang,Jung Gun Nam,Dong-Eon Lee,Dae-Young Lee,Gug Rae Jo,Jong G. Ok 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.1
While roll-to-roll nanoimprint lithography (R2R NIL) can be capitalized in highly scalable fabrication of nanopatterns, preparation of large-area flexible molds remains the main challenge. In this work, we demonstrate that tiling of small-area nanopatterns in a slightly overlapped fashion can provide a practical solution to it; sequentially performing the UV NIL processes onto self-replicable UV-curable resin drops by using a small tile mold can create largearea-tiled molds. We systematically investigated that controlling the tile NIL force and several parameters is crucial to minimize the seams between tiles. We also present that the R2R NIL system can be improved by integrating a linear UV LED module for prompt UV curing before the as-imprinted nanopattern reflows, which is critical for high-resolution, high-quality nanopatterning. By using the tiled mold containing 45 nm-half-pitch nanogratings and operating the UV LED-integrated R2R NIL system, we exemplify that sub 50 nm-resolution nanopatterns can be faithfully created.