• Journal of the Korean Chemical Society
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• v.33 no.3
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• pp.281-286
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• 1989

The redox properties of benzophydroxamic acid (Hben) and its oxovanadium complex, $VO(Ben)_2$ has been studied by the use of polarograpy and cyclic voltammetry. The radical anions of Hben seem to be generated in acetone. The wave at -0.05V vs. Ag/AgCl electrode might be attributed to the formation of radical anion and the wave at -1.78V vs. Ag/AgCl electrode might be attributed the formation of radical dianion. The $VO(Ben)_2$ exhibits one oxidation wave at + 0.55V and two reduction waves at -0.15V and -1.30V vs. Ag/AgCl electrode; the oxidation is reversible one electron process $(VO(ben)_2 {\rightleftharpoons} VO(ben)^+ + e)$. The reduction wave at -0.15V is quasireversible and is arised from the formation of radical anion,$VO(Ben)_2^-$. The second reduction wave at -1.30V is irreversible and this reduction process produces vanadium(III). This oxygen containing ligand of Hben seems to reduce the stability of + 4 oxidation state of vanadium while the sulfur or nitrogen donor of the ligands stabilize the + 4 oxidation state of vanadium when comparisons are made among several oxovanadium complexes.

• Journal of Plant Biotechnology
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• v.49 no.2
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• pp.155-161
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• 2022

This study investigated the antioxidant and anti-inflammatory effects of seed ethanol extracts from Rubus coreanus Miquel (SERC). To investigate the antioxidant activity, total polyphenol and flavonoid content, ABTS and DPPH radical scavenging activity, and reducing power were measured. The total polyphenol and flavonoid contents in seed ethanol extracts of R. coreanus Miq. were 4.09 ㎍ gallic acid equivalents (GAE)/mg and 16.25 ㎍ quercetin equivalents (QE)/mg, respectively. DPPH and ABTS radical scavenging activity showed concentration-dependent scavenging activity, and the RC₅₀ values of SERC were 26.68 ㎍/mL and 39.30 ㎍/mL, respectively. Moreover, the ferric reducing antioxidant power (FRAP) assay was performed to assess the reducing power, and SERC showed 0.61 ± 0.01 mM FeSO₄ E/mg. To measure the anti-inflammatory effect, the cytotoxicity and nitric oxide (NO) production inhibitory efficacy in RAW 264.7 cells was confirmed. SERC showed a NO production inhibitory effect at 500 ㎍/mL without cytotoxicity. As a result of verifying the antioxidant and anti-inflammatory activity using SERC, its potential as an antioxidant and anti-inflammatory material was confirmed.

• Korean Journal of Acupuncture
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• v.20 no.2
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• pp.47-54
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• 2003

목적 : 본 연구는 염증유발 내독소인 LPS 자극을 통한 면역 스트레스에 대한 약침의 치료효과와 기전을 알아보기 위해 설계되었다. LPS를 통한 염증반응은 다양한 기전을 통해 이루어지는 데 특히, 산화질소(NO)를 생성하는 효소인 iNOS의 활성은 시상하부에서 NO의 생성을 촉진함으로써 염증반응을 발현시키는 중요한 역할을 하는데 약침이 LPS로 인해 활성화된 iNOS의 발현에 어떠한 영향을 미치는지 알아보고자 하였다. 실험방법 : 흰쥐에 LPS를 투여하고 2시간 경과한 후 약침 (소염방, 대한약침학회)을 경혈 (합곡, 족삼리)에 좌,우 각각 0.2cc 씩 피하 투여하고 RT-PCR 방법을 통하여 면역활성에 중요한 역할을 하는 시상하부에서의 iNOS의 mRNA 발현을 알아 보았다. 실험결과 : LPS 투여로 인하여 증가하였던 iNOS mRNA가 약침치료를 통해 현저하게 감소하였다. 그러나 비경혈점 (미추부위 임의혈)에 약침을 투여한 군 경혈점에 생리식염수를 투여한 군에서는 iNOS mRNA 가 감소하지 않았다. 이는 약침이 LPS를 투여한 흰쥐의 시상하부에서 iNOS의 mRNA 발현에 조절작용을 가지고 있는 것을 보여주는 결과로 약침이 면역활성에 중요한 역할을 하는 NO의 생성을 억제함으로써 면역 스트레스에 치료효과를 나타내는 것으로 보여진다. 결론 : 본 연구는 약침치료가 면역반응의 중추기관인 시상하부에서 면역반응의 중요한 조절인자인 NO의 생성을 조절하는 기전을 통해 그 치료효과를 나타내는 것을 밝혔고 더 나아가 약침에 대한 현대과학적 연구에 중요한 발판을 마련했다는 점에서 그 의의를 가지고 있다고 사료된다.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.1-10
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• 2005

The purpose of this study was to evaluate the potential of a gamma irradiation to decompose 2,4,6-trinitrotoluene(TNT) in an aqueous solution. The decomposition reaction of TNT by gamma irradiation was a pseudo first-order kinetic over the applied initial concentrations($25{\sim}100mg/L$). The dose constant was strongly dependent on the initial TNT concentration. The removal of TNT was more efficient at pH below 3 and at pH above 11 than at neutral pH(pH 5-9). The required irradiation dose to remove over 99% of TNT was 40, 80 and 10 kGy, individually at pH 2, 7 and 13. The dose constant was increased by 1.6 fold and over 15.6 fold at pH 2 and 13, respectively, when compared with that at pH 7 When irradiation dose of 200 kGy was applied, the removal efficiencies of TOC were 91, 46 and 53% at pH 2, 7 and 13, respectively. Ammonia and nitrate were detected as the main nitrogen byproducts of TNT and glyoxalic acid and oxalic acid were detected as organic byproducts. The results showed that a gamma irradiation was an attractive method for the decomposition of TNT in an aqueous solution. However, regarding the application of high energy radiation for the TNT decomposition and mineralization, an application of an acidic pH below 3 to the solution before irradiation should be considered.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.193-193
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• 2000

박막 내의 잔류 응력은 막의 기계적 전기적 물성을 변화시키는 등 박막에 많은 영향을 끼치는 것으로 알려져 있다. 이러한 응력은 박막의 증착 공정중 여러 가지 증착 조건에 의해서 변화하게 되는데, 특히 스퍼터링 시스템의 경우에는 증착 압력과 사용하는 가스, 인가되는 전력 등 기본적인 증착조건들에 상당한 영향을 받는다. 이러한 영향은 금속 박막의 경우 상당히 잘 알려져 있다. 또한 반도체 공정에서 금속화 과정중 금속 전극의 단락등을 막기 위해 많은 연구가 진행되어 왔다. 본 논문에서는 고주파 마그네트론 스퍼터링 시스템을 사용하여 산화 아연(ZnO)을 증착하고 여러 공정 변수들에 따른 응력의 변화를 관찰하였다. 실험에서 ZnO 타겟을 사용하였으며, 작동 가스로는 아르곤과 산소를 사용하였다. 증착한 박막들은 모두 압축 응력을 보였으며, 박막의 응력에 가장 큰 영향을 미치는 요소들은 압력, 산소와 아르곤의 비, 기판과 타겟과의 거리 등이었는데, 인가 전력에는 거의 영향을 받지 않았다. 일반적으로 스퍼터링 시스템에서의 압축응력은 atomic peening에 의해서 형성되는데, 박막을 두드리는 높은 에너지의 아르곤이나 산소의 유량과 에너지의 1/2승에 비례하는 것으로 알려져 있다. 그러나 본 시스템에서는 인가 전력을 높여도 응력이 증가하지 않았고, 타겟과의 거리를 줄이면 오히려 응력이 감소함을 보였다. 이는 박막의 응력이 peening 하는 입자의 에너지뿐만이 아니라 증착되는 물질의 증착 속도와도 밀접한 관련이 있음을 보여준다. 즉, 증착속도가 증가하면 peening하는 입자가 끼치는 응력의 효과가 반감되기 때문으로 수식을 통해 증명할 수 있었다.진탄화 처리시간을 변화시켰을 때 화합물층의 생성은 ${\gamma}$'상으로부터 시작되고 $\varepsilon$상은 즉시 ${\gamma}$'상을 소모하면서 생성되어 일정시간이 지난 후 $\varepsilon$상은 안정화되며 질소가스농도가 증가할수록 화합물 층내의 $\varepsilon$상분율은 역시 증가하였다. 한편 CH4 가스농도는 처리되는 강종에 따라 차이를 보이며 적정 CH4 가스농도를 초과시에는 $\varepsilon$상 생성은 억제되고 시멘타이트상이 생성되었다.e에서 발생된 질소 플라즈마를 구성하는 이온들의 종류와 그 구성비율을 연구하였다.여러 가지 응용으로의 가능성을 가지고 있다. 그 예로 plasma processing, plasma wave에 의한 입자 가속, 그리고 가스 레이저 활성 매질 발생 등이 있다. 특히 plasma processing의 경우 helicon plasma는 높은 밀도, 비교적 낮은 자기장, remote operation 등이 가능하다는 점에서 현재 연구가 활발히 진행되고 있다. 상업용으로도 PMT와 Lucas Signatone Corp.에 서 helicon source가 제작되었다. 또한 높은 해리율을 이용하여 저유전 물질인 SiOF의 증착에서 적용되고 있다. 이 외에도 다수의 연구결과들이 발표되었다. 잘 일치하였다.ecursor 분자들이 큰 에너지를 가지고 기판에 유입되어 치밀한 박막이 형성되었기 때문으로 사료된다.을수 있었다.보았다.다.다양한 기능을 가진 신소재 제조에 있다. 또한 경제적인

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.337-340
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• 2014

In the present study, water extracts of Acanthopanax divaricatus var, albeofructus and Eleutherococcus divaricatus var. chiisanensis were prepared and their antioxidant and anti-inflammatory effects were compared. The water extract of Acanthopanax divaricatus var, albeofructus showed significantly higher activity in total polyphenol and flavonoid contents, while there were no significant differences in ABTS/DPPH radical scavenging activities and ferric reducing antioxidant power. However, the water extract of Eleutherococcus divaricatus var. chiisanensis at the highest dose showed significantly lower capacity in nitric oxide production than that of Acanthopanax divaricatus var, albeofructus. Taken together, there were differences between Acanthopanax divaricatus var, albeofructus and Eleutherococcus divaricatus var. chiisanensis in total polyphenol/flavonoid contents and anti-inflammatory effect, however, the antioxidant effect was almost similar.

• Journal of the Korean Institute of Gas
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• v.11 no.4
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• pp.17-22
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• 2007

The NOx emission characteristics with oxygen enrichment in non-premixed counterflow flames were investigated numerically. To consider systematically the situation of inevitable $N_2$ contamination by air infiltration in the process of pure-oxygen combustion, the volume ratio of $O_2$ in an oxidizer was changed from 21% to 100%. As a result the NO emission index $(EI_{NO})$ has the highest value under condition of 75% oxygen enrichment. This result can be explained by the change of $N_2$ destruction rate with oxygen enrichment rather than flame temperature, flame thickness and residence time. In particular, it was found that the reaction of N+NO=$N_2+O$ has the largest contribution on NOx production in oxygen-enrichment flames.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.50 no.1
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• pp.29-36
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• 2024

This study was carried out to identify the anti-inflammatory effects of Ishige foliacea (I. foliacea) extract on skin using RAW 264.7 cells. The anti-inflammatory effects of I. foliacea extract on RAW 264.7 cells were assessed by cell viability assay, mRNA expressions, and nitric oxide (NO)/prostaglandin E₂ (PGE₂) productions. The anti-inflammatory effects of I. foliacea extract were elucidated by analysis of IL-1α/IL-1β/IL-6/TNFα gene expressions and PGE₂/NO production. Quantitative real-time polymerase chain reaction showed that I. foliacea extract decreased the gene expression levels of iNOS/COX2/IL-1α/IL-1β and IL-6. Furthermore, PGE₂/NO production also revealed that I. foliacea extract exhibited anti-inflammatory properties. These results suggest that I. foliacea extract is an anti-inflammatory compound. It could be a potent cosmeceutical material for anti-inflammatory effects. Further studies on the anti-inflammatory mechanisms of broadleaf extracts are expected to help identify pharmacological mechanisms related to inflammation in addition to cosmeceuticals.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.8
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• pp.677-685
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• 2014

A direct carbon fuel cell (DCFC) generates electricity directly by converting the chemical energy in coal. In particular, a DCFC system with a solid oxide electrolyte and molten carbonate anode media has been proposed by SRI. In this system, however, there are conflicting effects of temperature, which enhances the ion conductivity of the solid electrolyte and reactivity at the electrodes while causing a stability problem for the anode media. In this study, the effect of temperature on the stability of a carbon-carbonate mixture was investigated experimentally. TGA analysis was conducted under either nitrogen or carbon dioxide ambient for $Li_2CO_3$, $K_2CO_3$, and their mixtures with carbon black. The composition of the exit gas was also monitored during temperature elevation. A simplified reaction model was suggested by considering the decomposition of carbonates and the catalyzed Boudouard reactions. The suggested model could well explain both the measured weight loss of the mixture and the gas formation from it.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.319-324
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• 2016

In this study, pitch-based carbon fibers in the acid were radiated with an electron beam to modify their surface, and surface changes were investigated according to each treatment conditions. Nitric acid and hydrogen peroxide were used as a drenched acidic solution and an electron beam dose was set to 200 and 400 kGy. The use of nitric acid introduced more oxygen functional groups on carbon fiber surfaces than that of using hydrogen peroxide, and also introduced nitrogen functional groups into the carbon fiber surface. In addition, oxygen functional groups introduced on carbon fiber surface increased as the electron beam dose increased due to the fact that the oxidizing material can be easily formed by e-beam radiation in nitric acid than the hydrogen peroxide, and also the higher energy electron beam dose can help forming more oxidizing materials. Moreover, the generation of C=O functional groups was favorable when using nitric acid because oxidizing C-OH functional groups to the C=O functional groups mainly occurred by $NO_2$ radicals generated by the electron beam radiation in a nitric acid solution.