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93.
Jung Hee Park Huahua Xue Jin Suk Jung Keungarp Ryu 《Korean Journal of Chemical Engineering》2012,29(10):1409-1412
Laccase from Trametes versicolor was readily immobilized on carbon nanomaterials including multiwalled carbon nanotubes (MWNTs), carboxylated multiwalled carbon nanotubes (MWNT-COOHs), and graphene oxides (GOs), by physical adsorption without using coupling agents. The immobilized amount of laccase strongly depends on the pH of the aqueous buffers of the immobilization mixture. As the pH of the aqueous buffer for immobilization increases, the immobilized amount of laccase decreases. The activity of the immobilized laccase on the three carbon nanomaterials exhibits a bell-shaped dependence on the pH of the immobilization solution with maximum activity at pH 6 or 7. When the immobilization solution becomes acidic or basic, the activity of the immobilized laccase declines significantly. The amount and the activity of immobilized laccase were maximum for graphene oxides as substrate material for immobilization. 相似文献
94.
Hye Kyung Choi Geun Cheol Song Hwe-Su Yi Choong-Min Ryu 《Journal of chemical ecology》2014,40(8):882-892
Plants are defended from attack by emission of volatile organic compounds (VOCs) that can act directly against pathogens and herbivores or indirectly by recruiting natural enemies of herbivores. However, microbial VOC have been less investigated as potential triggers of plant systemic defense responses against pathogens in the field. Bacillus amyloliquefaciens strain IN937a, a plant growth-promoting rhizobacterium that colonizes plant tissues, stimulates induced systemic resistance (ISR) via its emission of VOCs. We investigated the ISR capacity of VOCs and derivatives collected from strain IN937a against bacterial spot disease caused by Xanthomonas axonopodis pv. vesicatoria in pepper. Of 15 bacterial VOCs and their derivatives, 3-pentanol, which is a C8 amyl alcohol reported to be a component of sex pheromones in insects, was selected for further investigation. Pathogens were infiltrated into pepper leaves 10, 20, 30, and 40 days after treatment and transplantation to the field. Disease severity was assessed 7 days after transplantation. Treatment with 3-pentanol significantly reduced disease severity caused by X. axonopodis and naturally occurring Cucumber mosaic virus in field trials over 2 years. We used quantitative real-time polymerase chain analysis to examine Pathogenesis-Related genes associated with salicylic acid (SA), jasmonic acid (JA), and ethylene defense signaling. The expression of Capsicum annuum Pathogenesis-Related protein 1 (CaPR1), CaPR2, and Ca protease inhibitor2 (CaPIN2) increased in field-grown pepper plants treated with 3-pentanol. Taken together, our results show that 3-pentanol triggers induced resistance by priming SA and JA signaling in pepper under field conditions. 相似文献
95.
Sung Wook Hwang Hee Chang Ryu Sang Woo Kim Hae Youn Park Kwan Ho Seo 《应用聚合物科学杂志》2012,125(4):2732-2739
Maleic anhydride (MAH) was grafted onto ethylene vinyl acetate copolymer (EVA) in the internal mixer in the presence of dicumyl peroxide (DCP), and a prepared reactive compatibilizer, MAH-g-EVA, was blended with Poly (ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) (PETG). The gel content determination and element analysis (EA) was performed to confirm the grafting reaction. It was found that grafting reaction of MAH on to EVA could compete with crosslinking reaction of DCP during the modification process. In addition, the introduction of small amount of MAH showed a great effect on reducing gel content by decreasing crosslink reaction. As MAH content increased, grafted MAH concentration increased, whereas the grafting yield decreased. It was also confirmed that MAH-g-EVA acted as a reactive compatibilizer in the blend with PETG, and enhanced compatibility by reacting with the hydroxyl end groups, OH, of PETG. Addition of EVA in the blend leads a plastic deformation of PETG, and MAH had a great effect on enhancing interfacial adhesion resulting in significant increasing of % strain; however, improved compatibility could not be changed much in low strain tensile strength and Young's modulus. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
96.
Donghyeon Lee Yujin Cheon Jun-Hyung Ryu In-Beum Lee 《International Journal of Hydrogen Energy》2017,42(40):25518-25530
Molten Carbonate Fuel Cell (MCFC) has been emerging as a promising renewable power system. It is still challenging to operate the MCFC to meet its varying demands because of its nonlinearity and complex dynamics. This paper proposes a novel MCFC operation framework based on PID auto-tuning control. A case study is presented to illustrate the applicability of the strategy with some comments. 相似文献
97.
In social network services, such as Facebook, Google+, Twitter, and certain postings attract more people than others. In this paper, we propose a novel method for predicting the lifespan and retweet times of tweets, the latter being a proxy for measuring the popularity of a tweet. We extract information from retweet graphs, such as posting times; and social, local, and content features, so as to construct prediction knowledge bases. Tweets with a similar topic, retweet pattern, and properties are sequentially extracted from the knowledge base and then used to make a prediction. To evaluate the performance of our model, we collected tweets on Twitter from June 2012 to October 2012. We compared our model with conventional models according to the prediction goal. For the lifespan prediction of a tweet, our model can reduce the time tolerance of a tweet lifespan by about four hours, compared with conventional models. In terms of prediction of the retweet times, our model achieved a significantly outstanding precision of about 50%, which is much higher than two of the conventional models showing a precision of around 30% and 20%, respectively. 相似文献
98.
Commercial process for mass production of synthetic natural gas through the adiabatic reactors: operational characteristics of a 50‐kW pilot‐plant,influence of steam,and CO2 下载免费PDF全文
Suk‐Hwan Kang Jin‐Ho Kim Ki‐Jin Jung Young‐Don Yoo Kwang‐Jun Kim Dong‐Jun Koh Jae‐Hong Ryu 《国际能源研究杂志》2017,41(3):353-364
In synthetic natural gas (SNG) reaction process, the water gas shift (WGS) reaction and methanation reaction take place simultaneously, and an insufficient supply of steam might deactivate the catalyst. In this study, the characteristics of the methanation reaction with a commercial catalyst and using a low [H2]/[CO] mole ratio in SNG synthesis are evaluated. The reaction characteristics at various possible process parameters are evaluated varying different process parameters such as the [H2O]/[CO] mole ratio, [H2]/[CO] mole ratio, flow of different % CO2, and reaction temperature. Temperature profiles on catalyst bed are monitored as a function of the [H2O]/[CO] mole ratio, [H2]/[CO] mole ratio, and flow of different % CO2. Through a lab‐scale optimization process, suitable optimum conditions are selected and in the same condition a 50‐kW pilot‐scale SNG production process through adiabatic reactors is carried out. The pilot scale SNG reaction is stable through overnight and the CO conversion efficiency and CH4 selectivity are 100% and 97.3%, respectively, while the maximum CH4 productivity is 0.654 m3/kgcat · h. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
99.
Jun-Tae Kim Seo Hee Jung Sun Young Kang Chung-Kyu Ryu Nam Sook Kang 《International journal of molecular sciences》2014,15(11):20403-20412
We report the discovery of aurora kinase inhibitor using the fragment-based virtual screening by multi-docking strategy. Among a number of fragments collected from eMololecules, we found four fragment molecules showing potent activity (>50% at 100 μM) against aurora kinase. Based on the explored fragment scaffold, we selected two compounds in our synthesized library and validated the biological activity against Aurora kinase. 相似文献
100.
You Jeong Eum Jungho Ryu Chang Young Koo Jung Min Park Jai-Yeoul Lee Hee Young Lee 《Ceramics International》2021,47(5):6371-6375
Magnetoelectric (ME) property modulation in heterostructured (Ni0.5Zn0.5)Fe2O4/Pt/Pb(Zr0.3Ti0.7)O3 (NZFO/Pt/PZT) thin films on platinized Si substrate by thermal annealing condition variation was studied. In an attempt to prevent interfacial reaction between NZFO and PZT layers during high temperature annealing, thin Pt layer was deposited which can serve as inter-diffusion barrier as well as electrode. The ferroelectric, magnetic, and ME properties of the heterostructured film were noticeably modulated due to microstructural evolution and clamping relaxation developed during thermal annealing process. Room temperature ME voltage coefficient of the heterostructured thin films was enhanced with increasing annealing temperature and reached to 29 mV/cm·Oe when annealed at 650 °C. 相似文献