• Title/Summary/Keyword: 물 분해

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Selective modulation of charge carrier transport of photo-anode in PEC cell by a graphitized fullerene interfacial layer (C70이 도입 된 물분해 수소생산용 텅스텐 산화물의 광촉매 특성 연구)

  • Hong, Eun-Mi;Kim, Min-Gyeong;Lee, Ju-Yeol;Park, Seon-Yeong;Mul, Guido;Im, Dong-Chan
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.150-150
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    • 2014
  • 지구상 존재하는 화석연료의 고갈에 대한 우려와 함께 최근 들어 지구 온난화로 인해 야기되고 있는 심각한 지구환경 문제에 대한 관심이 고조되고 있다. 이산화탄소로 대표되는 지구 온난화를 일으키는 공해물질의 많은 부분이 현재 주에너지원으로 사용되는 화석연료에 기인하기 때문에 이를 대체할 수 있는 청정에너지 개발은 이미 세계적 당면 과제라고 할 수 있다. 그 중, 수소에너지는 청정에너지로써의 역할 뿐만 아니라 에너지 저장매체로써의 기능 또한 담당할 수 있어 주목 받고 있다. 본 연구에서는 텅스텐 광촉매를 사용하여 물을 수소와 산소로 분해 하고자 하였고 C70을 도입하여 분해 효율을 향상시키고자 하였다.

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Selective modulation of charge carrier transport of photo-anode in PEC cell by a graphitized fullerene interfacial layer (C70의 도입 및 반응면적에 따른 물분해 수소생산용 텅스텐 산화물의 광촉매 특성 연구)

  • Hong, Eun-Mi;Im, Dong-Chan
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2015.05a
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    • pp.102-102
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    • 2015
  • 지구상 존재하는 화석연료의 고갈에 대한 우려와 함께 최근 들어 지구 온난화로 인해 야기되고 있는 심각한 지구환경 문제에 대한 관심이 고조되고 있다. 이산화탄소로 대표되는 지구 온난화를 일으키는 공해물질의 많은 부분이 현재 주에너지원으로 사용되는 화석연료에 기인하기 때문에 이를 대체할 수 있는 청정에너지 개발은 이미 세계적 당면 과제라고 할 수 있다. 그 중, 수소에너지는 청정에너지로써의 역할 뿐만 아니라 에너지 저장매체로써의 기능 또한 담당할 수 있어 주목 받고 있다. 본 연구에서는 텅스텐 광촉매를 사용하여 물을 수소와 산소로 분해 하고자 하였고 C70을 도입하여 분해 효율을 향상시키고자 하였다.

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낙동강 퇴적물내 중금속의 존재형태별 분포에 관한 연구

  • 김은호;김형석;성낙창
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2000.05a
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    • pp.219-220
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    • 2000
  • 낙동강 유역 퇴적물내 중금속의 존재형태를 Tessier 등의 연속추출법으로 조사해본 결과 퇴적물내 함유된 중금속의 존재형태는 혐기성 환경, pH 및 유기물의 분해 등수환경의 변화에 따라 상이 한 것으로 평가되었다.

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Response of hydrolyzed polyacrylonitrile fibers to pH (가수분해 폴리아크릴로니트릴 섬유의 pH 응답성)

  • 우종형;서영삼;윤기종;조재환;정재윤
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.04a
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    • pp.345-346
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    • 2003
  • 폴리아크릴로니트릴을 NaOH로 가수분해시키면 carboxylate anion과 carboxamide기가 생성되며, 물을 흡수할 경우 sodium carboxylate기의 해리로 팽윤이 크게 일어나므로 고흡수성을 지니게 된다[l]. 일반적으로 섬유가 팽윤을 하면 수축하며, 가수분해된 폴리아크릴로니트릴 섬유는 흡수되는 물 속의 염의 농도 또는 pH에 따라 팽윤도가 다르기 때문에 가수분해된 시간과 pH조건 변화에 따라서 수축하는 정도가 다르다. 과거의 연구결과에 의하면 아크릴 섬유는 2M HCI에서 최소의 길이로 수축하며, 2M NaOH에서 최대의 길이가 나타난다고 하였다[2]. (중략)

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Study on the decomposition of 1,1,2-trichloroethane in a pyrolysis reactor and a numerical study for scale-up design (열분해 반응기에서 1,1,2-trichloroethane의 분해특성과 Scale-up 설계를 위한 수치해석적 연구)

  • 이채복;라승혁;강경태;김상용
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.11a
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    • pp.417-418
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    • 2002
  • 열분해는 독성이 강한 염화탄화수소의 처리뿐만 아니라 염화물을 효과적으로 제거하여 이들로부터 유용한 탄화수소를 얻을 수 있는 반응이다 Biomass에 열분해를 적용하여 가스상, 액상, 고상형태의 유동한 부산물로 전환시키고 있으며 현재 액상생성물은 외국에서 큰 주목을 받고 있는 부산물이다. 1,1,2-trichloroethane(TCE)는 독성이 강한 휘발성 유기화합물(VOC)이며 발암물질이다. (중략)

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Effect of Sodium Caseinate Hydrolysates on Angiotensin-I Converting Enzyme Inhibition Activity (Sodium Caseinate 가수분해물의 Angiotensin-I Converting Enzyme 저해효과에 관한 연구)

  • Lee, Keon-Bong;Shin, Yong-Kook;Baick, Seung-Chun
    • Food Science of Animal Resources
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    • v.32 no.5
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    • pp.652-658
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    • 2012
  • This study was carried out to identify the ACE (Angiotensin converting enzyme) inhibitory activity of casein hydrolysates for development of anti-hypertensive hydrolysates. Sodium caseinate was treated with six kinds of commercial proteases such as Flavourzyme, Protamex, Neutrase 1.5, Alcalase, Protease M, and Protease S for 8 h individually, and was then treated with the enzyme combination for 4 h at $45^{\circ}C$. The hydrolysate which had the highest ACE inhibitory effect was then hydrolysed successively with three digestive enzymes: pepsin, trypsin, and ${\alpha}$-chymotrypsin, at $37^{\circ}C$ for 4 h under conditions mimicking those of the gastrointestinal tract. UF (ultra filtration) treatment was applied to one of the secondary hydrolysates to determine ACE inhibitory activity. When sodium caseinate was hydrolysed by commercial proteases, the degree of hydrolysis (DH) showed 2.54 to 4.25% and after secondary hydrolysis, DH showed 4.30 to 5.22%. ACE inhibitory activity and $IC_{50}$ values decreased, and inhibition rates increased during hydrolysis. Protamex treatment showed the lowest $IC_{50}$ value ($516{\mu}g/mL$) and Flavourzyme hydrolysate showed the highest $IC_{50}$value ($866{\mu}g/mL$). As the first hydrolysate was treated with Flavourzyme, the ACE inhibitory activity increased. Neutrase hydrolysate had the highest activity with an $IC_{50}$ value ($282{\mu}g/mL$). When Neutrase plus Flavourzyme treatment was hydrolyzed by digestive enzymes, the $IC_{50}$ value ($597{\mu}g/mL$) was decreased statistically (p<0.05). As Neutrase plus Flavourzyme hydrolysate is treated by UF with MW cut-off 10,000, permeate showed $273{\mu}g/mL$ of $IC_{50}$ value, showed no difference, but retentate which has over MW 10,000 showed statistically different $IC_{50}$ value, $635{\mu}g/mL$ (p<0.05).

Hydrolysis of Aluminum Nitride Powder (AlN 분말의 가수분해 특성)

  • 최상욱;정홍식;황진명
    • Journal of the Korean Ceramic Society
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    • v.31 no.1
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    • pp.79-87
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    • 1994
  • Aluminum nitride was hydrolyzed in contact with water, evolving the reaction heat of 172 cal/g within 12 hours to form alumina trihydrates. At 4$0^{\circ}C$ >, amorphous alumina hydrate was easily produced by the spontaneous breaks of AlN particle at the beginning of the hydrolysis process, while bayerite was formed by the dissolution-recrystallization processes of amorphous alumina hydrate at the temperature between 4$0^{\circ}C$ and 6$0^{\circ}C$, and pseudo-boehmite was generated on the surface of AlN particle by the condensation process of the corresponding phase at 6$0^{\circ}C$ <. The longer the hydrolysis timje or the higher the value of pH in solution, the more the bayerite phase was produced. However, pseudo-boehmite was easily generated under the following favorable conditions; when the hydrolysis reaction occured rapidly at the beginning and when the absorption of OH radical on the surface of AlN particle was disturbed by ethyl alcohol in a solution. However, aluminum nitride was hardly hydrolyzed in a solution of pH 2.0.

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Antimutagenic Effects of Extracts of Curry Powder and Its Individual Spice (카레분 및 향신료 추출물의 항 돌연변이 효과)

  • 정승현;정명수;이진선;박기문
    • Food Science of Animal Resources
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    • v.22 no.4
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    • pp.352-357
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    • 2002
  • Antimutagenic effects of extracts from curry powder and its individual fourteen kinds of spices, were investigated by Ames test. The antimutagenic effects against a direct mutagen, 2-nitrofluorene(2 -NF) and two indirect mutagens, 2-anthramine(2-AT) and 2-acetamidofluorene (2-AE) in the S. typhimurium TA98 were tested. For the 2-NF, the antimutagenicity of cinnamon, fenugreek, fennel, ginger, clove, turmeric and celery seed were determined as 42, 38, 32, 28, 24, 23 and 20%, respectively. The antimutagenicity of clove against the 2-AT was the highest (116%), and followed by the order of celery seed(103%), cardamon(100%), red pepper(99%), cinnamon(92%), cumin(83%), ginger(82%), fennel(82%), coriander (71%), nutmeg(68%) and turmeric (55%). The results also showed that the antimutagenic effect of clove against the 2-AF was superior to other spices. In case of curry powder among more than 10 kinds of spices, the antimutagenenicity against the 2-AT and 2-AF showed 23% and 6%, respectively, but no effect was observed against the 2-NF.

Production of Spirulina Extract by Enzymatic Hydrolysis (효소 가수분해 방법을 이용한 스피루리나 추출물의 제조)

  • In, Man-Jin;Gwon, Su-Yeon;Chae, Hee-Jeong;Kim, Dong-Chung;Kim, Dong-Ho
    • Applied Biological Chemistry
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    • v.50 no.4
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    • pp.304-307
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    • 2007
  • An efficient production method of spirulina extract was developed by enzymatic treatment using cell lytic and proteolytic enzymes. The suitable dosage of Tunicase, a cell lytic enzyme, was found to be 2.0% (w/w). Proteolytic enzymes were screened to obtain high solid recovery and spirulina extraction (SE) index, which indicates nucleic acid-related substances content. Among the seven tested proteases, Esperase was selected and optimal dosage of this enzyme was 2.0% (w/w). The solid recovery and SE index of simultaneous treatment and co-treatment using optimal dosages of Tunicase and Esperase were greatly similar, respectively. However, co-treatment had the effect of shortening total hydrolysis time. The SE index and solid recovery of co-treatment were significantly enhanced by 75% $(11.4{\rightarrow}20.0)$ and 45% $(45.2%{\rightarrow}65.3%)$, respectively, than those of the non-treated extracts.

Optimal conditions of enzymatic hydrolysis for producing anti-inflammatory peptides from sandfish (Arctoscopus japonicus) hydrolysate (도루묵 가수분해물 유래 항염증 펩타이드 제조를 위한 효소 가수분해 최적 조건)

  • Jang, Hye Lim;Yoon, Kyung Young
    • Korean Journal of Food Science and Technology
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    • v.50 no.2
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    • pp.203-208
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    • 2018
  • In this study, the hydrolysis conditions for the production of anti-inflammatory peptides from meat and roe hydrolysates of sandfish (Arctoscopus japonicus) were determined by measuring the nitric oxide (NO) scavenging enzymatic activity, experimental pH, temperature, enzyme concentration, and hydrolysis time. The optimal conditions determined when using meat hydrolysate were a pH value of 5.0, at a temperature of $30^{\circ}C$, 1% enzyme concentration, and 4 h hydrolysis time. The optimal conditions when using roe hydrolysate were a pH of 5.0, a temperature of $70^{\circ}C$, enzyme concentration of 3%, and hydrolysis time of 3 h. The NO scavenging activities of meat and roe hydrolysate were determined to be 18.94 and 19.81%, respectively. In summary, this study determined the optimum enzymatic hydrolysis conditions for the production of anti-inflammatory peptides from sandfish.