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971.
MinJoong Kim JuYoung Youn JeongHoon Lim KwangSup Eom EunAe Cho HyukSang Kwon 《International Journal of Hydrogen Energy》2018,43(24):11363-11371
High-temperature corrosion of metallic bipolar plates is a main problem to limit system reliability of molten carbonate fuel cells (MCFCs). In particular, cathode current collector (CCC) and wet-seal area in the bipolar plates suffer severe corrosion during MCFCs operation. Herein, we are trying to explore facile and cost-effective coating materials and methods to enhance corrosion resistance of CCC and wet-seal area of MCFCs. Cobalt (Co) layer was coated by using electrodeposition method for CCC, and aluminum (Al) layer was coated by using mechanical cladding method for wet-seal area. Co and Al layers were transformed into in-situ lithiated oxides, which are LiCoO2 and LiAlO2, by reacting with electrolytes without detachment. These in-situ formed oxides efficiently impede formation and growth of corrosion scales by preventing permeation of electrolytes. We believe that Co electrodeposition and Al cladding would be suitable and practical methods for making protective layers to enhance corrosion resistance of CCC and wet-seal area in the MCFCs bipolar plates. 相似文献
972.
Nikola Ruhswurmova Soohyun Kim Jiho Yoo Donghyuk Chun Youngjoon Rhim Jeonghwan Lim Sangdo Kim Hokyung Choi Sihyun Lee 《International Journal of Hydrogen Energy》2018,43(33):15880-15890
Ethyl acetate is a volatile organic compound (VOC) that has emerged as a major environmental pollutant and also one of representative components of bio-oil. In this study, mostly metallic Ni particles (size: <10 nm) were finely dispersed on low-rank coal (LRC) by the ion-exchange process. Catalytic steam reforming of ethyl acetate (EA) was performed over Ni supported on Eco LRC (Ni/Eco) to reduce EA emissions and simultaneously produce H2. EA reforming over 17.7 wt% Ni/Eco at 400 °C results in H2 yield of 70%–80%; this is comparable to that achieved with reforming over commercial Ni/Al2O3. Advantageously, metallic Ni particles are dominant over Ni oxides on LRC, and therefore, the pre-reduction step routinely required for an alumina-supported catalyst can be skipped. Furthermore, deactivation by coking is slower with Ni/Eco than with Ni/Al2O3 during long-term operation, probably because of the smaller particle size and preferential adsorption on the coal support. 相似文献
973.
Chang-Hyun Kim Jae-Yun Han Sehwa Kim Boreum Lee Hankwon Lim Kwan-Young Lee Shin-Kun Ryi 《International Journal of Hydrogen Energy》2018,43(15):7684-7692
With the aim of producing hydrogen at low cost and with a high conversion efficiency, steam methane reforming (SMR) was carried out under moderate operating conditions in a Pd-based composite membrane reactor packed with a commercial Ru/Al2O3 catalyst. A Pd-based composite membrane with a thickness of 4–5 μm was prepared on a tubular stainless steel support (diameter of 12.7 mm, length of 450 mm) using electroless plating (ELP). The Pd-based composite membrane had a hydrogen permeance of 2.4 × 10?3 mol m?1 s?1 Pa?0.5 and an H2/N2 selectivity of 618 at a temperature of 823 K and a pressure difference of 10.1 kPa. The SMR test was conducted at 823 K with a steam-to-carbon ratio of 3.0 and gas hourly space velocity of 1000 h?1; increasing the pressure difference resulted in enhanced methane conversion, which reached 82% at a pressure difference of 912 kPa. To propose a guideline for membrane design, a process simulation was conducted for conversion enhancement as a function of pressure difference using Aspen HYSYS®. A stability test for SMR was conducted for ~120 h; the methane conversion, hydrogen production rate, and gas composition were monitored. During the SMR test, the carbon monoxide concentration in the total reformed stream was <1%, indicating that a series of water gas shift reactors was not needed in our membrane reactor system. 相似文献
974.
Jin Ha Lee Doman Kim Young-Hwan Moon Yeon-Jin Jeong Kyung-Joo Seong Hoi-Soon Lim Sun-Hun Kim Won-Jae Kim Ji-Yeon Jung 《Food science and biotechnology》2010,19(5):1397-1401
(−)-Epigallocatechin-3-gallate (EGCG) has been reported to inhibit cellular proliferation and induce apoptosis in a range
of cancer cells. This study examined the cytotoxicity of EGCG glucoside on human laryngeal epidermoid carcinoma Hep2 cells.
The EGCG glucoside treatment decreased the cell viability in Hep2 cells. Furthermore, EGCG glucoside caused apoptotic morphological
changes with chromatin condensation and nuclear fragmentation, as observed by a terminal deoxynucleotidyl transferase dUTP
nick end labeling (TUNEL) assay and activated caspase-3 immunohistochemisty. However, the EGCG glucoside did not induce the
production of reactive oxygen species (ROS), suggesting that oxidative stress is not involved in the apoptotic response. EGCG
glucoside induces apoptosis in Hep2 cells through not the generation of ROS, but the activation of caspase-3. 相似文献
975.
Sae Bom Lim Jagan Mohan Rao Tingirikari Ji Sun Seo Ling Li Sangmin Shim Jin-Ho Seo Nam Soo Han 《Food science and biotechnology》2018,27(1):73-78
Lactic acid bacteria (LAB) are key for the fermentation of sourdoughs to improve the quality and nutritive value of bread. The aim of this study was to isolate the LAB starter for sourdough fermentation from Jeung-pyun, a Korean traditional rice cake. Among the twenty two LAB screened, five isolates were selected based on exo-polysaccharide production. Among them, three isolates showed cell growth greater than 8.5 Log CFU/g, maximum increase in the volume of dough, and dextran concentration up to 0.16%. During the sourdough fermentation, pH and total titratable acidity (TTA) were changed, as the three isolates synthesized lactic acid and acetic acid with fermentation quotients less than 2.0. They were identified as Leuconostoc lactis EFEL005, Lactobacillus brevis EFEL004, and Le. citreum EFEL006. They displayed good fermentation properties (growth, dextran production, pH, and TTA) in dough and they are regarded as potential starters to be used in sourdough fermentation. 相似文献
976.
977.
Physical aging of glassy corn starch and its effect on the physical properties of compressed starch bars were investigated by using differential scanning calorimetry (DSC), dynamic mechanical thermal analyzer (DMTA), and Instron texturometer. Amorphous corn starch samples were prepared by drying a starch paste, followed by compressing the dried powders to bar‐type specimens under heat (100°C, 1.38×107 Pa). These bars were then aged at 25°C for up to 22 days, after which thermal and mechanical characteristics were determined. There were progressive increases in glass transition temperature and relaxation enthalpy during the aging, which reached limiting values as structural equilibrium of the amorphous matrix was approached. The peak temperature of the relaxation endotherm (DSC thermogram) changed with time in a trend similar to the relaxation enthalpy. The storage modulus (DMTA) increased with aging time, but the peak intensity of tan δ decreased. The breaking strength (Instron texturometer) increased gradually with time of aging and reached a maximum. It has been demonstrated the relaxation kinetics for glassy amorphous corn starch can be characterized by both thermal and mechanical properties, such as relaxation enthalpy, storage modulus, and breaking strength. 相似文献
978.
Yoo Byoung-Wook Kim Bom Joshi Pankaj Kwon Sung-Ok Kim YeonJin Oh Jung-Sook Kim Jeongseon Oh Se-Young Lim Ji-Ae Choi Byung-Sun Kim Yu-Mi Eom Sang-Yong Hong Young-Seob Sohn Seok-Joon Park Kyung-Su Pyo Heesoo Kim Ho Ha Mina Park Jung-Duck Kwon Ho-Jang Lee Sang-Ah 《Food science and biotechnology》2018,27(4):1227-1237
Food Science and Biotechnology - This study was aimed to examine the association the blood/urinary concentration of toxic metal (Hg, Pb, and Cd) with children’s dietary patterns. This... 相似文献
979.
980.