• Title/Summary/Keyword: GT

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A study on characteristics of SOFC/GT system for the supply gas flow rates (공급가스 유량에 따른 SOFC/GT 시스템 특성에 관한 연구)

  • Park, Sang-Kyun;Lee, Joo-Hee;Park, Geong-Dae;Choi, Jae-Hyuk
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.7
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    • pp.765-772
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    • 2015
  • In this research, the characteristics of SOFC/GT (Solid Oxide Fuel Cell/Gas Turbine) system temperature, stack power and system efficiency for flow rates of air, CH4 and water supplied to SOFC stack have been investigated. The temperature of the gas supplied to cathode and anode of SOFC stack in the SOFC/GT system are maintained by utilizing exhaust gas without the addition of external heat source. As a result, within the scope of this study, temperatures of gas supplied to cathode and anode of SOFC stack were maintained at 1000 (K) by utilizing the exhaust gas of the SOFC/GT system without the addition of external heat source. The system efficiency is increased with increase of air flow rate supplied to the stack and with decrease of $CH_4$ flow rate supplied to the stack. In addition, it can be found that the flow rate of the exhaust gas supplied to the turbine had a significant effect on the system efficiency. And the efficiencies of SOFC stack and SOFC/GT system depending upon various operating conditions of the SOFC/GT system is 51~57% and 57~73%, respectively.

Characterization of a Novel Thermostable Oligopeptidase from Geobacillus thermoleovorans DSM 15325

  • Jasilionis, Andrius;Kuisiene, Nomeda
    • Journal of Microbiology and Biotechnology
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    • v.25 no.7
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    • pp.1070-1083
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    • 2015
  • A gene (GT-SM3B) encoding a thermostable secreted oligoendopeptidase (GT-SM3B) was cloned from the thermophile Geobacillus thermoleovorans DSM 15325. GT-SM3B is 1,857 bp in length and encodes a single-domain protein of 618 amino acids with a 23-residue signal peptide having a calculated mass of 67.7 kDa after signal cleavage. The deduced amino acid sequence of GT-SM3B contains a conservative zinc metallopeptidase motif (His400-Glu401-X-XHis404). The described oligopeptidase belongs to the M3B subfamily of metallopeptidases and displays the highest amino acid sequence identity (40.3%) to the oligopeptidase PepFBa from mesophilic Bacillus amyloliquefaciens 23-7A among the characterized oligopeptidases. Secretory production of GT-SM3B was used, exploiting successful oligopeptidase signal peptide recognition by Escherichia coli BL21 (DE3). The recombinant enzyme was purified from the culture fluid. Homodimerization of GT-SM3B was determined by SDS-PAGE. Both the homodimer and monomer were catalytically active within a pH range of 5.0–8.0, at pH 7.3 and 40℃, showing the Km, Vmax, and kcat values for carbobenzoxy-Gly-Pro-Gly-Gly-Pro-Ala-OH peptidolysis to be 2.17 ± 0.04 × 10-6 M, 2.65 ± 0.03 × 10-3 µM/min, and 5.99 ± 0.07 s-1, respectively. Peptidase remained stable at a broad pH range of 5.0–8.0. GT-SM3B was thermoactive, demonstrating 84% and 64% of maximum activity at 50℃ and 60℃, respectively. The recombinant oligopeptidase is one of the most thermostable M3B peptidase, retaining 71% residual activity after incubation at 60℃ for 1 h. GT-SM3B was shown to hydrolyze a collagenous peptide mixture derived from various types of collagen, but less preferentially than synthetic hexapeptide. This study is the first report on an extracellular thermostable metallo-oligopeptidase.

Performance Analysis of Hybrid SOFC/GT/ST System for Marine Power Applications (선박동력용 SOFC/GT/ST 하이브리드시스템의 성능 평가에 관한 시뮬레이션)

  • Lee, Kyung-Jin;Oh, Jin-Suk;Kim, Sun-Hee;Oh, Sae-Gin;Lim, Tae-Woo;Kim, Jong-Su;Lee, Jae-Hyun;Park, Sang-Kyun;Kim, Mann-Eung;Kim, Myoung-Hwan
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.1
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    • pp.40-50
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    • 2012
  • The electrification of the waste heat of stack is necessary to enhance the efficiency of fuel cell system. For this purpose, the hybrid SOFC/GT/ST system is suitable. The purpose of this work is to predict the performance of methane fueled SOFC/GT/ST hybrid power system and to analyze the influence of operating temperature of stack, current density of stack, and gas turbine pressure ratio. According to the analysis, it is proved that the SOFC/GT/ST hybrid system suppress the rapid decrease in efficiency and lead to the significant improvement of efficiency as compared with SOFC system.

Gallotannin regulates apoptosis and COX-2 expression via Akt and p38kinase pathway in human lung cancer cell line, A549

  • Yu, Seon-Mi;Gweon, Eun-Jeong;Chung, Ki-Wha;Kim, Kwang-Hoon;Cho, Hong-Sik;Kim, Song-Ja
    • Animal cells and systems
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    • v.16 no.5
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    • pp.366-375
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    • 2012
  • Gallotannin (GT) is derived from plant poly phenol and is associated with biological actions in a wide range of cells. In this study, we evaluated the effect of GTon apoptosis and cyclooxygenase-2 (COX-2) expression and attempted to shed light on the mechanism of action in A549 human lung carcinoma cells. We found that GT dramatically induced apoptosis as demonstrated by expression of p53 and active caspase-3 via western blot analysis and fragmented DNA as detected by DNA fragmentation and DAPI staining. We also observed that GT significantly causes COX-2 expression in a dose-dependent manner determined by western blot analysis. Phosphorylation of Akt and p38 was considerably increased by GT in A549 human lung carcinoma cells. Inhibition of Akt and p38kinase with LY294002 or SB203580 suppressed GT-induced apoptosis and COX-2 expression. Furthermore, we have shown that prevention of COX-2 with NS398 or indomethacin does not any effects on apoptosis induced by GT. Taken together, our present results suggest that GT regulates apoptosis and COX-2 expression through Akt and p38kinase pathway in A549, human lung carcinoma cells.

A study on Surfactants for Electrokinetic Soil Remediation (동전기적 토양복원에 적합한 계면활성제의 선정)

  • 이현호;박지연;김상준;이유진;양지원
    • Journal of Soil and Groundwater Environment
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    • v.8 no.1
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    • pp.1-8
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    • 2003
  • Three different surfactants, APG, Brij30, and SDS, were tested to study the characteristics of sorption on soil surfaces, washing ability, biodegradability, and electrokinetic removal. Kaolinite and phenanthrene were selected as a model soil and a representative HOC, respectively. Phenanthrene was sorbed on kaolinite up to 2,200 mg/kg dry soil. The APG, Brij30, and SDS were sorbed on soil to 40, 7, and 4g/kg soil, respectively. The washing ability of phenanthrene was in order of Brij30>SDS>APG. The biodegradability tested with sludge was in order of APG>Brij30>SDS. In the electrokinetic test, the highest removal efficiency was obtained with APG that exhibited the highest electroosmotic flow. To increase the removal efficiency of HOC in the electrokinetic remediation, the most important factor was the selection of surfactant which maximized the electroosmotic flow.

Ganglioside GT1b increases hyaluronic acid synthase 2 via PI3K activation with TLR2 dependence in orbital fibroblasts from thyroid eye disease patients

  • Yoo, Hyun Kyu;Park, Hyunju;Hwang, Hye Suk;Kim, Hee Ja;Choi, Youn-Hee;Kook, Koung Hoon
    • BMB Reports
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    • v.54 no.2
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    • pp.136-141
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    • 2021
  • Thyroid eye disease (TED) is a complex autoimmune disease with a spectrum of signs. we previously reported that trisialoganglioside (GT)1b is significantly overexpressed in the orbital tissue of TED patients, and that exogenous GT1b strongly induced HA synthesis in orbital fibroblasts. However, the signaling pathway in GT1b-induced hyaluronic acid synthase (HAS) expression in orbital fibroblasts from TED patients have rarely been investigated. Here, we demonstrated that GT1b induced phosphorylation of Akt/mTOR in a dose-dependent manner in orbital fibroblasts from TED patients. Both co-treatment with a specific inhibitor for PI3K and siRNA knockdown of TLR2 attenuated GT1b-induced Akt phosphorylation. GT1b significantly induced HAS2 expression at both the transcriptional and translational level, which was suppressed by specific inhibitors of PI3K or Akt/mTOR, and by siRNA knockdown of TLR2. In conclusion, GT1b induced HAS2 in orbital fibroblasts from TED patients via activation of the PI3K-related signaling pathway, dependent on TLR2.

The Development of the Web Based Cutting Parameter Selection System Using Group Technology (GT를 이용한 Web 기반 절삭변수 검색시스템의 개발)

  • Lee, Sung-Youl;Kwak, Kyu-Sup
    • IE interfaces
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    • v.15 no.3
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    • pp.308-315
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    • 2002
  • This study presents the web based cutting parameter selection system using Group Technology (GT). The GT is basically applied to classify and code the work material and cutting process which are main factors to affect cutting parameter selection. The proposed system has been designed to electronically select proper cutting conditions based on the stored GT database. The existing approaches used in most small and medium sized companies are basically to use manufacturing engineer's experience or to find the recommended values from the manufacturing engineers handbook. These processes are often time consuming and inconsistent, especially when a new engineer is involved. Consequently, the proposed system could automatically and consistently generate the proper cutting conditions (feed, depth of cut, and cutting speed) as soon as relatively simple data input is given thanks to the classified GT database.

Study on the Modeling of the Intake and Exhaust Systems of an SI Engine Using GT-POWER (GT-POWER를 이용한 SI 기관 흡·배기 계통의 모델링에 관한 연구)

  • Kim, Jeong-Seok;Yoon, Keon-Sik;Woo, Seok-Keun
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.6
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    • pp.779-785
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    • 2011
  • Prediction of the transient pressure variations and performance parameters has been carried out for an SI engine using one of commercial software, GT-POWER. Various models were applied for the calculation of properties of the plenum chamber, exhaust manifold and catalytic convertor which are very important components included in the intake and exhaust systems.

Pilot Scale Assessment of DOC and THMs Removal in Conventional Water Treatment System

  • Lee, Choong-Dae;Lee, Yoon-Jin
    • Journal of Environmental Science International
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    • v.15 no.9
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    • pp.829-834
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    • 2006
  • This research aims to investigate the behavior of organic matter that causes bacterial re-growth and the formation of disinfectant by-products such as THM in water treatment, and to optimize conditions for a more efficient and conventional water facility. THM removed 51 % and 12 % through coagulation/sedimentation and filtration using a selected conventional system. In this experiment, the removal ratio of DOC was highest at 68 % when the Gt value was 42,000 and lowest at 41 % when the Gt value was 30,000. 77-84 % of total DOC was removed during coagulation/sedimentation, and 15-23 % was removed during filtration. When Gt values were between 30,000 and 66,000, over 50 % of high molecular matter above 10 K during coagulation/sedimentation was removed. Turbidity removed 98 % when the G1 value was 66,000. As the Gt value increased, the turbidity removal ratio increased. Turbidity removed over 20 % during the filtration process.

A Study on the Hybrid Production System of MRP, GT and JIT (MRP, GT, JIT 혼합생산시스템 구축에 관한 연구)

  • 이현용;이승우;강경식
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.58
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    • pp.89-100
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    • 2000
  • There use many production management systems for increasing productivity, minimizing inventory, keeping due dates and maximizing use of resources. MRP, GT and JIT are popular among these systems. There use many production management systems for increasing productivity, minimizing inventory, keeping due dates and maximizing use of resources. MRP, GT and JIT are popular among these systems. In this study, we had designed mixed production system which integrated searching and grouping function of GT, purchasing function of JIT and based on MRP and developed related algorithms and applied systems. The developed system was based on appling renewed algorithms for existing MRP system. To test efficiency operated real-data but we have tested renewed algorithms using sample-data because of massive real-data.

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