• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.157-160
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• 2007

The catalyst layer of a proton exchange membrane (PEM) fuel cell is a mixture of polymer, carbon, and platinum. The characteristics of the catalyst layer play critical role in determining the performance of the PEM fuel cell. This research investigates the role of catalyst layer composition using a Central Composite Design (CCD) experiment with two factors which are Nafion content and carbon loading while the platinum catalyst surface area is held constant. For each catalyst layer composition， polarization curves are measured to evaluate cell performance at common operating conditions, Electrochemical Impedance Spectroscopy (EIS), and Cyclic Voltammetry (CV) are then applied to investigate the cause of the observed variations in performance. The results show that both Nafion and carbon content significantly affect MEA performance. The ohmic resistance and active catalyst area of the cell do not correlate with catalyst layer composition, and observed variations in the cell resistance and active catalyst area produced changes in performance that were not significant relative to compositions of catalyst layers.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.59-65
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• 2019

There are various subtypes of cells in cancer tissues, but it is hard to confirm their composition experimentally. Here, we estimated the cell composition of each sample from gene expression data by using statistical machine learning approaches, two different regression models and investigated whether the cell composition was different between cancer and normal tissue. As a result, we found that CD8 T cell and Neutrophil were increased in oral cancer tissues compared to normal tissues. In addition, we applied t-SNE, which is one of the unsupervised learning, to verify whether normal tissue and oral cancer tissue can be clustered by the derived cell composition. Moreover, we showed that it is possible to predict oral cancer and normal tissue by several supervised classification algorithms. The study would help to improve the understanding of the immune cell infiltration at oral cancer.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.26-32
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• 1998

The chemical composition of differentiating xylem of Populus deltoides M. were investigated and compared with those from sapwood. The cell wall polysaccharides were extracted sequentially from a differentiating xylem and sugar composition was analyzed with G.L.C, H.P.L.C and gel chromatograpy. The pectin substance and hemicellulose are rich in the cell wall of differentiating xylem. The $H_2O$ extract polysaccharides from differentiating xylem were composed with xylose-glucose residues which seem to be xyloglucan and a pectin. The arabinogalactan and the mannan were extracted with $Na_2CO_3$ solution and also the xylan was extracted with KOH solution. Sugar composition of each fractions in gel filteration of purified $H_2O$ polysaccharide suggests that the xyloglucan can be extracted with $H_2O$ from differentiating xylem.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.143-150
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• 1996

The membrane fatty acid composition of tumor cell can be modified either in cell by altering the lipid composition of the medium of during growth in animals by changing the dietaty fat composition. These modifications are associated with changes in membrane physical properties and certain cellular functions, including carrier-mediated transport and enzyme contained within the membrane. Such effects influence the transport of nutrients and chemotherapeutic agents in cancer cells .Fatty acid modification also can enhance the sensitivity of the neoplastic cell to chemotherapy. The alteration in plasma membrane composition will be affected through dietary supplementations and the potential value to cancer patients could be a better understanding of the effects of diet on responsiveness of neoplasms to chemotherapy, i.e. cancer patients' chances for a "cure" can be improved by diet changes prior to treatment.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.6
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• pp.514-523
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• 2021

This study investigated the effect of anode fuel composition on the performance of direct borohydride/hydrogen peroxide fuel cells (DBHPFCs). The effect of sodium borohydride (NaBH₄) and sodium hydroxide (NaOH) concentrations on fuel cell performance was determined through fuel cell tests. Fuel cell performance increased with an increase in the NaBH₄ concentration, whereas it decreased with an increase in the NaOH concentration. The anode fuel composition was selected as 10 wt% NaBH₄+10 wt% NaOH+80 wt% H₂O based on the fuel viscosity, electrochemical reaction rate, and decomposition reaction rate. DBHPFCs were also tested to analyze the effect of operating temperature and operation time on fuel cell performance. The present results can be used as a reference basis to determine operating conditions of DBHPFCs.

• Journal of Food Hygiene and Safety
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• v.10 no.3
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• pp.147-153
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• 1995

The ethanol extract from the root bark of Morus alba showed the strongest antimicrobial activity on the growth of almost all the tested microorganisms which were food-borne pathogens and food-related microorganisms. Therefore, fatty acid composition, amino acid composition and shape change of microorganisms treated with the ethanol extract from the root bark of Morus alba were examined. In effects of treatment with the ethanol extract on the fatty acid compositions of B. subtilis, S. aureus and E. coli, fatty aicd compositions such as hexadecanoic acid (16:0) and octadecanoic acid (18:2) of the tested strains were increased but pentadecanoic acid (15:0) heptadecanoic acid (17:0) and acid (16:1) and octadecenoic acid (18:1) of E. coli were decreased. The ethanol extract did not significantly affect the aminn acid composition of the tested strains. Transmission electron micrographs of microorgani는 treated with the ethanol extract exhibited morphological changes that irregularly contracted cell surface in S. aureus and destructed cell walls in B. subtilis and E. coli.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.423-427
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• 1999

Electroplating of 80%Ni permalloy thin plate for magnetic core materials. was studied The convected flow of electrolyte was used for stirring methode. The current density could be increased up to 250mA/$\textrm{cm}^2$ by flow cell. The composition of electroplated layer with vespect to current density and flow rate was investigated and experimental equation to predict the composition was made. How cell yielded more uniform thickness distribution than paddle cell did. The composition distribution was also studied. The thickness was the most important factor to the permeability. The permeability of 5$\mu\textrm{m}$plated permalloy was over 2000 at 1 MHz.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.5 s.113
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• pp.25-34
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• 2005

The chemical composition of the differentiating xylem of Populus deltoides M. was investigated and compared with that of sapwood. The cell wall polysaccharides were extracted sequentially from adifferentiating xylem and fractionated with gel chromatography. The sugar composition of each fraction was analyzed with G..C and H.P.L.C. The cell wall of the differentiating xylem is rich with the pectin substance and hemicellulose compared with that of sapwood. The water-extracted polysaccharides from the differentiating xylem were composed mainly of xylose and glucose residues. The sugar composition of some of the fractions in the gel filtration of purified $H_{2}O$ polysaccharide suggest that xyloglucan was extracted with $H_{2}O$ from differentiating xylem. Also, we can supposed that the purified $H_{2}O$ polysaccharide might be xyloglucan from the spectrometric data(IR and NMR) of purified $H_{2}O$ polysaccharide.

• Journal of Sasang Constitutional Medicine
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• v.24 no.3
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• pp.80-92
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• 2012

Objectives The purpose of this study is to investigate the effects of korean herbal bathing extracts composition 1 and composition 2 on Th2 cytokine production in MC/9 mast cells. Methods The effects of composition 1, 2 was analyzed by ELISA and Real-time PCR in MC/9 mast cells. Levels of IL-5, IL-13 were measured using enzyme-linked immunosorbent assays(ELISA). mRNA levels of IL-4, IL-5, IL-6, IL-13 were analyzed with Real-time PCR. Results Composition 1, 2 inhibited the IL-5, IL-13 production significantly(p<.001) in comparison to PI-control group at concentration of 100 ${\mu}g/mL$, 200 ${\mu}g/mL$. Composition 1, 2 inhibited the IL-4, IL-5, IL-13 mRNA expression significantly in comparison to PI-control group at concentration of 100 ${\mu}g/mL$, 200 ${\mu}g/mL$. Composition 1 inhibited the IL-6 mRNA expression significantly in comparison to PI-control group at concentration of 200 ${\mu}g/ml$. Composition 2 inhibited the IL-6 mRNA expression significantly in comparison to PI-control group at concentration of 100 ${\mu}g/mL$, 200 ${\mu}g/mL$. Conclusions These results indicate that composition 1, 2 has the effect of decreasing the Th2 cytokine production in the MC/9 mast cell.

• Korean Journal of Pharmacognosy
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• v.40 no.4
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• pp.357-364
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• 2009

Phospholipids are crucially important in a cell membrane function and could thereby influence antibiotic susceptibility. In order to investigate the antifungal mechanism the total lipid was extracted from C. albicans treated with citronellol or thymol in concentration of their minimum inhibiting concentration and the changes in phospholipids composition were analyzed using ketoconazole as control. The cell growth and total lipid synthesis in cell walls of C. albicans were inhibited by treatment with citronellol. The levels of total lipids were decreased by 35.85% compared to the control. They also showed a significant decrease in the contents of phospholipid, phosphatidylcholine(PC), phosphatidyl ethanolamine(PE) and phosphatidylinositol(PI). As the result of GC assay for total fatty acid methyl esters of PC, PE and PI in C. albicans treated with citronellol, it was found that the major fatty acid composed of three phospholipid were palmitic acid, stearic acid and oleic acid. Moreover, the pattern of the fatty acid compositions of PC, PE and PI were changed by the oil. Based on the results, the anti-Candida mechanism of citronellol or thymol might be closely associated with disrupting the permeability barriers of the fungal cell wall composition or construction.