• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.513-513
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• 2009

최근 바이오디젤의 원료로 미세조류가 많은 관심을 끌고 있다. 미세조류는 물, 이산화탄소와 태양광을 이용해 광합성 성장이 가능하며, 지질(오일) 성분이 풍부하여 바이오디젤의 원료로 이용할 수 있다. 미세조류는 단위 면적당 오일 생산량이 곡물류의 50-100배 이상이며, 이산화탄소를 기질로 이용하므로 온실가스 직접 저감이 가능하다. 또한 배양시 비경작지나 황무지를 사용할 수 있으므로 기존 식용작물과 경쟁하지 않으며, 하수, 해수, 폐수 등 다양한 물자원을 이용할 수 있다. 본 연구에서는 고농도 $CO_2$에 내성을 지닌 Chlorella sp. KR-1을 대상으로 1 L 규모 기포탑 광생물반응기에서 균체 성장 및 지질(바이오오일) 합성에 대한 $CO_2$ 농도, 가스 공급속도, 질산염 농도 등 환경 및 영향 조건의 영향을 조사하였다. 가스 공급속도 0.4 L/min에서 $CO_2$ 농도를 0.03-20% 범위에서 조사하였을 때 최대 균체성장은 $CO_2$ 10%에서 관찰되었다. 균체내 지방산 함량은 $CO_2$ 농도 0.03%에서 가장 낮았고, 5-20% 범위에서는 $CO_2$ 농도 증가에 따라 감소하는 경향이 관찰되었다. 가스 공급속도를 0.2 L/min에서 0.8 L/min으로 증가시켰을 때 최대 균체농도는 0.6-0.8 L/min의 범위에서 관찰되었고, 생체내 최대 지방산 함량은 0.4 L/min에서 관찰되었다. Nitrate 농도 1-20 mM 범위에서 최종 균체농도는 nitrate 농도 증가에 따라 10mM까지 증가하였으나 그 이상에서는 증가하지 않았다. 반면 지방산 함량은 nitrate 농도 증가에 따라 감소하는 경향이 관찰되었다. 본 실험에서 얻은 최대 지방산 생산량은 1,100 mg/L이었으며, 주요 지방산은 C10:0(1.7%), C16:0(28.5%), C18:0(11%), C18:1n9c(25.9%), C18:2n6c(26.3%), C18:3n3(6.6%)이었다. 현재 100 L 규모 광생물반응기에서 석탄발전소 배가스($CO_2$ 12-15%, SOx 50ppm, NOx 100ppm)를 이용한 바이오오일 생산 실험이 진행 중이다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.4
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• pp.399-404
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• 2021

From 1 January 2020, the limit for Sulphur in fuel oil used on board ships operating outside designated emission control areas will be reduced to 0.5 %. This regulation by international maritime organization (IMO) is able to significantly reduce the amount of Sulphur oxides (SOx) discharging from ships and should have environmental advantages and health for all over the world. To meet the regulation, in these days, wet scrubber system is being actively developed. However, this process leads to make washing wastewater. In this study, we evaluated ion exchange resin system in accordance with scrubber wastewater discharge regulation by IMO. Theoretical wastewater used as feed solution of lab scale water treatment systems. The results revealed that nitrate ion was removed selectively in spite of high TDS wash wastewater solution depending on ion exchange resin property. Moreover, it was possible to improve efficiency of the system by optimizing operating conditions.

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.743-748
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• 2019

This study focuses on the simulation of wet flue gas desulfurization process for improving the production of gypsum by the utilization of low-grade limestone. At present, high-grade limestone with a $CaCO_3$ content of 94% is used for producing merchantable gypsum. In modeling process, a lot of reactions are considered to develop model. First, the limestone dissolution is simulated by RSTOIC model. Second, SOx absorption and crystallization is used by RCSTR model. Finally the gypsum is separated by using SEPERATORS model. Modeling steps make it easy to reflect further side reactions and physical disturbances. In optimization condition, constraints are set to 93% purity of gypsum, 94% desulfurization efficiency, and total use of limestone at 3710 kg/hr. Under these constraints, the mass flow of low-grade limestone was maximized. As a result, the maximum blending quantity of low-grade limestone for 2,100 kg of high-grade limestone that satisfies constraints is about 1,610 kg.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.1981-1987
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• 2013

In order to use the excellent features of saponin and phenolic compounds in the leaf and fruit of ginseng, ginseng fruit Yakgwa (GFY), ginseng leaf Yakgwa (GLY) and ginseng root Yakgwa (GRY) were made via adding the fruit, leaf and root powder in the process of making Yakgwa, and the properties were investigated. When making Yakgwa, GFY and GLY had superior expansion compared to GRY. 2.5-GFY (added 2.5% ginseng fruit powder) and 2.5-GLY (added 2.5% ginseng leaf powder) increased about 1.68 times and had better expansion than the control; however, when more amount of fruit and leaf were added, the expansion was decreased. The GFY and GLY showed green and red color, and the brightness and yellowness were decreased. Oil absorption during making Yakgwa showed to increase as the amount of fruit and leaf powder were increased regardless of the ginseng parts. Hardness of Yakgwa increased as the root additives were increased, and it decreased when leaf and fruit were added. The results of sensory evaluation on ginseng-based Yakgwa showed that oily taste was lowered as the amount of fruit and leaf additives were increased, which had increased the preference. On the overall preference of Yakgwa, 5.0-GFY, 2.5-GLY and 7.5-GRY was high, which contained 2.30 mg/g, 1.02 mg/g, and 0.91 mg/g of saponin, respectively.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.967-974
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• 2004

The osteoblastic cell activity is important for born formation, thus, this study was performed to investigation of that the effect of edible sources, Rubus coreanus Miquel (RCM), on the proliferation and differentiation of MC3T3-E1 osteoblastic like cell. The effects of RCM extract on cell proliferation were measured by MIT assay. At 1, $10\;{\mu}g/mL$ of RCM extract treated, that were elevated of cell proliferation to 103 and $142\%$ via control, respectively. And the cell differentiation were measured as alkaline phosphatase (ALP) activity at 3, 9, 18, and 27 days. As the results, the $10\;{\mu}g/mL$ was increased ALP activity more than 2.6 times compared with control, 1.4 times via positive control at 27th day (p<0.05). The optical concentration of RC extract was rechecked by ALP staining and Alizarin Red staining for investigation of the induction of ALP activity, nodule formation by mineralization. mRNA expression analysis showed that the RCM $(10\;{\mu}g/mL)$ increased in SOX9 as well as ALP in MC3T3-E1 cells. These results suggest that RC extract was stimulates the MC3T3-E1 cell proliferation and differentiation.

• Journal of the Korean Institute of Gas
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• v.14 no.3
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• pp.41-45
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• 2010

The physical properties of DME(Dimethyl Ether) are very similar to LPG and well-mixed. As cetane number of DME is similar to diesel fuel that can replace diesel fuel and alternative energy. DME is a clean energy source that can be manufactured from various raw materials such as natural gas, CBM(Coal Bed Methane) and biomass. DME has no carbon-carbon bond in its molecular structure and its combustion essentially generates no soot as well as no SOx. The development of DME process in KOGAS have 4 section. First, syngas section can be manufactured various syngas ratio. This completes the tri-reforming process for the synthesis gas ratio of approximately 4.0 to 1.0 range can be adjusted. Second, $CO_2$ is removed from the $CO_2$ removal section of about 92~99%, so the maximum concentration of $CO_2$ entering the DME synthesis reactor should not exceed 8%. Third, in the DME synthesis section, if the temperature of DME reactor increases, the activity of DME catalyst increased. but for the long-term activity is desirable to maintain the proper temperature. Finally, the purity of DME in the DME purification section is over 99.6%.

• BMB Reports
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• v.49 no.10
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• pp.548-553
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• 2016

Mesenchymal stem cells (MSCs) are widely used in cartilage tissue engineering to repair articular cartilage defects. However, hypertrophy of chondrocytes derived from MSCs might hinder the stabilization of hyaline cartilage. Thus, it is very important to find a suitable way to maintain the chondrogenic phenotype of chondrocytes. It has been reported that cordycepin has anti-inflammatory and anti-tumor functions. However, the role of cordycepin in chondrocyte hypertrophy remains unclear. Therefore, the objective of this study was to determine the effect of cordycepin on chondrogenesis and chondrocyte hypertrophy in MSCs and ATDC5 cells. Cordycepin upregulated chondrogenic markers including Sox9 and collagen type II while down-regulated hypertrophic markers including Runx2 and collagen type X. Further exploration showed that cordycepin promoted chondrogenesis through inhibiting Nrf2 while activating BMP signaling. Besides, cordycepin suppressed chondrocyte hypertrophy through PI3K/Bapx1 pathway and Notch signaling. Our results indicated cordycepin had the potential to maintain chondrocyte phenotype and reconstruct engineered cartilage.

• Korean Journal of Organic Agriculture
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• v.19 no.3
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• pp.385-396
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• 2011

This study was carried out to develop environmental friendly control for major diseases and pests on Boxthorn (Lycium chinense Mill.). Outbreak of Eighteen diseases and pests were found at the Boxthorn organic yards in Chung-nam province. Among them Powdery mildew (Erysiphe polygoni de Cand.), Hypophyllous mold (Pseudocercospora chengtuensis (Tai)), Western flower trips (Frankliniella occidentalis (Pergande)), Green peach aphid (Myzus pericae (Sulzer)) and Corn earworm (Helicoverpa armigera) needed to be controled by environmental friendly methods for high fruit yield of organic Boxthorn. In summer(Jun) test Bacilus subtilis QST 713 wettable powder and Sulfur wettable powder were effective and in autumn (Sep.) test Sulfur, Copper hydroxide and Paraffinic oil were relatively effective in Powdery mildew. In Hypophyllous mold control test Paraffinic oil and Bacilus subtilis GB - 0365 were effective with above 70% control value. And it was possible to control Western flower trips by natural enemy (Orius laevigatus) by 80% control value. Corn earworm was possible to control by Bacillus thuringiensis subsp. aizawai GB413 flowable and Bacillus thuringiensis aizawa 0423 wettable powder application above 70%. And Green peach aphid was controllable with environmental friendly materials, such as, Bacillus subtilis (Seoncho), Bacillus subtilis (Jinsami) above 80% and Ginkgo nut extract above 70% control value.

• Journal of Ginseng Research
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• v.45 no.3
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• pp.433-441
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• 2021

Background: Multiple sclerosis (MS) and its animal model, the experimental autoimmune encephalomyelitis (EAE), are primarily characterized as dysfunction of the blood-brain barrier (BBB). Ginsenoside-Rg3-enriched Korean Red Ginseng extract (Rg3-KRGE) is known to exert neuroprotective, anti-inflammatory, and anti-oxidative effects on neurological disorders. However, effects of Rg3-KRGE in EAE remain unclear. Methods: Here, we investigated whether Rg3-KRGE may improve the symptoms and pathological features of myelin oligodendroglial glycoprotein (MOG)_35-55 peptide - induced chronic EAE mice through improving the integrity of the BBB. Results: Rg3-KRGE decreased EAE score and spinal demyelination. Rg3-KRGE inhibited Evan's blue dye leakage in spinal cord, suppressed increases of adhesion molecule platelet endothelial cell adhesion molecule-1, extracellular matrix proteins fibronection, and matrix metallopeptidase-9, and prevented decreases of tight junction proteins zonula occludens-1, claudin-3, and claudin-5 in spinal cord following EAE induction. Rg3-KRGE repressed increases of proinflammatory transcripts cyclooxygenase-2, inducible nitric oxide synthase, interleukin (IL)-1 beta, IL-6, and tumor necrosis factor-alpha, but enhanced expression levels of anti-inflammatory transcripts arginase-1 and IL-10 in the spinal cord following EAE induction. Rg3-KRGE inhibited the expression of oxidative stress markers (MitoSOX and 4-hydroxynonenal), the enhancement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) and NOX4, and NADPH activity in the spinal cord of chronic EAE mice. Furthermore, apocynin, a NOX inhibitor, mimicked beneficial effects of Rg3-KRGE in chronic EAE mice. Conclusion: Our findings suggest that Rg3-KRGE might alleviate behavioral symptoms and pathological features of MS by improving BBB integrity through modulation of NOX2/4 expression.

• Journal of Korea Port Economic Association
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• v.39 no.3
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• pp.47-60
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• 2023

A thorough inventory of ship emissions, particularly ship's emission of in-port area is necessary to identify significant sources of exhaust gases such as NOx, SOx, PM, and CO₂ and trends in emission levels over time, and reduce their serious effects on the environment and human health. Therefore, the goal of this study is to assess the volume of emissions from ships in Mokpo port, which serves as a gateway to the southwest coast of Korea, using a bottom-up methodology and data from the automatic identification system (AIS) and the Korean Port Management Information System (Port-MIS). In this work, an analysis of ship movement utilizing AIS data and an actual set of data on ship specification were gathered. By examining ship movement using AIS data, We also proposed a new approach for identifying cruising/maneuvering mode. Finally, the results were classified by ship operating mode, by exhaust gas, by ship type, and by berth, which provides a thorough and in-depth analysis of the air pollution caused by ships in Mokpo port.