• Journal of the Korean Wood Science and Technology
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• v.44 no.1
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• pp.147-155
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• 2016

Pulp made from sugarcane bagasse (SCB) was bleached in element chlorine free (ECF) sequence. The peroxide bleaching process for the final bleaching process has been introduced in order to reduce the use of chlorine dioxide. Prior to peroxide bleaching, different chelating chemicals were applied. When 4.5% of the total chlorine dioxide was used, bleached SCB pulp using additional DTPA chelate stage (DEDQP) resulted in 87.0% of the ISO brightness. However, bleached pulp using simultaneous stage of DTPA chelate and chlorine dioxide (DE(DQ)P) was reached at 83.9% of the ISO brightness. The viscosity of DEDQP bleached pulp was 25.6 cPs, and the one of DE(DQ)P bleached pulp was 21.9 cPs. Decreasing of chelate effect by chlorine dioxide led to a decrease in the final brightness and a lower viscosity. But simultaneous stage of EDTA chelate and chlorine dioxide (DE(DQ)P) led to higher final brightness (87.0% ISO) and higher viscosity (25.8 cPs) than those of the $DEDQ_{EDTA}P$ bleached pulp (86.4% ISO, 25.2 cPs).

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.4-5
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• 2000

오늘날 현대사회의 산업화 과정에서 발생되는 여러 문제 중에서도 가장 시급하고 절실하게 해결하여야 할 문제중의 하나는 극심한 오염 문제이다. 그 중에서도 대기오염은 자동차의 급격한 증가와 겨울철 난방연료의 사용으로 머지않아 우리나라 환경정책의 가장 큰 숙제로 떠오를 전망이다. 즉, 수질오염은 개인차원에서 어느 정도 자구책을 마련할 여지가 있지만 대기오염은 개인의 의지로 개선이 불가하고 불특정다수에게 광범위하게 영향을 미치기 때문에 그 폐해가 더욱 심각하다. 각종 오염원으로부터 배출되는 불소화합물, 질소산화물, 황화물, 오존, 메탄가스, 이산화탄소 등 다양한 종류의 대기오염 물질들은 광화학 스모그, 지구온난화, 자연림감소, 오존홀, 산성비 등의 원인을 제공하며, 인체 및 자연 생태계에 예측하기 어려운 부작용들을 야기시키고 있다. (중략)

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.272-275
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• 2005

본 실험은 염소계유해유기화합물을 처리하는 목적으로 종래의 초임계수산화법의 결점을 완전히 해결하기 위해서 도달한 것이 질산나트륨을 산화제로서 사용하는 개량된 초임계수 산화법(다단계산화법)이다. 이와 같이 본 연구팀이 개발한 개량된산화법(다단계산화법)은 매우 간단하며 저렴한 염소계유기물 분해처리시스템을 구축하는 것이 가능하다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.697-699
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• 2008

• Food Industry And Nutrition
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• v.9 no.1
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• pp.28-35
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• 2004

피니톨(pinitol, 3-O-methyl-chiro-inositol, PI)은 콩류나 솔잎 등에 포함되어 있는 천연 혈당강하 성분으로서 myo-inositol(MI)의 구조이성체인 chiro-inositol(CI)의 3번 탄소에 methyl기가 붙은 ether 화합물이다(Fig. 1). 1990년대 초 미국의 Virginia대 학 연구진들은 일반인들과는 달리 당뇨병 환자들의 소변에는 chiro-inositol의 함량이 현저히 낮다는 사실을 발견하고 chiro-inositol이 인체 내에서 혈중포도당 대사에 어떻게 관여하는지 밝혀내었다(1,2). (중략)

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.69-71
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• 2003

토양 및 수질 유기물질과 금속 산화물사이의 상호 반응관계는 환경지구화학적으로 중요하게 다루어진다 (Sposito, 1984). 토양내 광물들의 표면은 토양 유기물질의 주요한 부분을 차지하는 휴믹물질, 즉 휴믹산과 펄빅산에 의해서 이온강도와 산도에 따라 피복하는 현상을 일으킨다. 특히, 휴믹산과 펄빅산은 토양 및 수질내 주요한 구성 유기물로 존재하며 다양한 유기화합물과 분자량을 갖으며, 중금속들의 유출에 의한 오염 환경에서 그 화학종과 이동도에 영향을 주게된다 (Thurman, 1985). (중략)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1037-1041
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• 2004

공액계 유기가교로서 butadiene을 사용한 이핵 유기금속착체를 합성하였고, 합성된 유기금속착체 화합물에 대한 구조적 특징과 두 금속간의 전기화학적 특성에 관한 연구를 수행하였다. $[Cp*Fe(CO)_2]_2-({\mu}-CH=CH-CH=CH)$ 착체는 $Cp*(CO)_2$FeK와 cis-3,4-dichlorocyclobutene과의 반응으로 합성하였고, 이 착체에 결합된 CO기는 UV 광반응하에서 $PPh_3$로 치환시켜 $[Cp*Fe(CO(PPh)_3]_2-({\mu}-CH=CH-CH=CH)$를 합성하였다. 합성된 착체에 대한 전기화학적 특성을 파악하기 위해 CV 실험결과, 전위차 ${\Delta}E^{\circ}=0.575{\sim}0.605$ V이고 $K_c$값은 $109{\sim}1010$으로 매우 큰 값을 얻음으로서 두 금속간의 상호작용이 탄화수소사슬을 통해 활발하게 이루어지고 있음을 알수가 있었다.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.299-307
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• 1996

The surface tension of PO added sodium poly(oxyethylene(EO), oxyisopropylene(PO)) dodecyl ether sulfate firstly were slightly lower than EO added sulfate in the concentration range of $10^{-6}{\sim}10^{-3}mol/{\ell}$. And they had lower critical micelle concentration ($10^{-4}{\sim}9{\times}10^{-5}mol/{\ell}$) than general anionic surfactants. The adsorptivity ($2.2{\times}10^{-10}mol/cm^2$) of sodium $(PO)_{10}(EO)_5$ dodecyl ether(compound of PO addition firstly) calculated by Gibbs' adsorption isotherm were higher than that of sodium $(EO)_{10}(PO)_5$, dodecyl ether(compound of EO addition firstly), but were lower than that of sodium dodecyl sulfate (${\Gamma}=3.2{\times}10^{-10}mol/cm^2$). These could be understood that the adsorption areas of compounds were very large because of their high molecular weight. Moreover, PO compounds showed better properties than EO compounds in foamability, emulsifying power for organics (n-hexane, benzene), detergency for the lard, tallow oil mixture and dispersability for iron oxide. It was interpreted in terms of surface properties of the PO compounds. These showed that the interfacial activity become higher when hydrophilic and hydrophobic portion existed in aggoromerated state respectively. The test results of emulsifying power for organics (n-hexane, benzene) showed better for benzene than n-hexane. Eight kinds of sodium (EO, PO) dodecyl ether derivatives showed irregular dispersibilities for polar iron oxide in water dispersed media.

• Food Science and Preservation
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• v.15 no.6
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• pp.891-896
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• 2008

Total phenolics and flavonoids, and the antioxidant capacity of plum cultivar wines (Prunus salicina L. cv. Soldam and P. salicina L. cv. Formosa) were determined using spectrophotometric methods. The total phenolic and flavanoid contents of Soldam wine were $478.4\;{\pm}\;5.6\;mg$ GAE and $202.4\;{\pm}\;7.5\;mg$ CE per L,respectively, and in Formosa wine were $200.6\;{\pm}\;7.5\;mg$ GAE and $64.4\;{\pm}\;6.8\;mg$ CE per L, respectively. Neutral and acidic phenolics in Soldam wine were extracted with ethyl acetate and 0.01 N HCl, respectively. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay, neutral phenolics (64.5 EDA%) had $3{\sim}4$ times higher antioxidant activity than acidic phenolics (21.5 EDA%) and other related phenolic compounds such as chlorogenic acid (15.5 EDA%) and quercetin (24.6 EDA%) at a concentration of $100\;{\mu}g/mL$. The antiviral activities of neutral and acidic phenolics in Soldam wine were investigated in vitro using a virus-induced cytopathic effect (CPE) inhibition assay. Results showed that neutral and acidic phenolics at concentrations of $100\;{\mu}g/mL$ inhibited porcine epidemic diarrhea virus (PEDV) replication at rates of 78.12% and 58.37%, respectively. The inhibition rate of 10 g/mL neutral phenolics (69.42%) was higher than that of ribavirin as an antiviral reagent (57.86%). At concentrations of $100\;{\mu}g/mL$ or less, neutral and acidic phenolics of Soldam wine had no cytotoxic effect against vero cells.

• Journal of Korea Foundry Society
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• v.41 no.1
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• pp.3-10
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• 2021

In the compound casting between the aluminum alloy and the cast iron, the iron component may be dissolved from the cast iron during the process and mixed into the aluminum melt, thereby forming various iron-containing intermetallic compounds and significantly deteriorating the tensile properties of the aluminum alloy. On the other hand, unlike Fe, which is added as an impurity, Cu is added to improve the mechanical properties of the aluminum alloy. In this study, the change in microstructure and tensile properties of aluminum alloys due to the addition of Fe and Cu was investigated. A large amount of iron-containing compounds such as coarse Al₅FeSi phases were formed when the iron content was 1% or more, and the tensile properties were significantly reduced. In the case of the aluminum alloy to which Cu was added, an Al₂Cu phase was additionally formed and the tensile strength was clearly improved.