• 대한토목학회논문집
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• 제28권3A호
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• pp.407-415
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• 2008

슬래그의 팽창성 붕괴는 주로 Free-CaO의 수화 반응이 주된 원인으로 분석되고 있으며, 이 문제의 해결 방안을 마련하기 위해 여러 기관에서 연구가 진행되고 있고, 더불어 콘크리트용 골재로의 활용 방안을 지속적으로 연구하고 있다. 현재, 국내에서는 고로 슬래그에 대한 연구는 많이 이루어지고 있지만, 전기로 및 전로 슬래그와 같은 제강 슬래그에 대한 연구는 극히 미비한 실정이다. 이에, 본 연구의 주재료인 전기로 산화 슬래그의 기초적인 물성 분석뿐만 아니라, 화학적인 메커니즘을 규명하여 콘크리트용 잔골재로서의 활용 가능성을 분석하고, 실생활에 응용하는데 그 목적이 있다고 하겠다. 그렇기 때문에, 본 연구의 진행 방향으로 전기로 산화 슬래그의 성분 분석과 함께 기본 물성을 측정하고, 이후에 중/장기 강도 및 세부적인 내구성 분석을 실시하여, 시멘트 콘크리트 적용의 적합성 평가 후, 규격을 제안하는 절차를 밟았다. 본 연구에 대한 기대 효과는 산업 부산물의 활용에 따른 환경 보전 및 재활용이라는 측면 이외에도, 전기로 산화 슬래그의 시멘트 콘크리트용 잔골재서의 상용화에 있다고 하겠다.

• Journal of Plant Biology
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• 제30권3호
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• pp.181-187
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• 1987

Copper inhibited PSII-mediated O2 evolution (H2OlongrightarrowDCIP, H2OlongrightarrowSiMo) but not PSImediated O2 uptake(DCIP. Asc.longrightarrowMV) in isolated Chinese cabbage chloroplasts. Copper toxicity on PSII-mediated O2 evolution was higher at alkaline condition than at acidic condition and was inhanced by light illumination after copper treatment. The increased toxicity by light illumination was not recovered by subsequent dark treatment. The inhibitory effect of copper on H2OlongrightarrowDCIP reaction was higher than that on H2OlongrightarrowSiMo reaction. This result suggests that there may be another inhibitory site of copper on PSII other than water oxidizing side of PSII.

• 상하수도학회지
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• 제26권3호
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• pp.399-408
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• 2012

The overall goal of this study was to characterize and quantify ammonia-oxidizing bacteria (AOB) in four different full-scale sequence batch reactor (SBR) wastewater treatment plants. Also, this study focused on assessing the occurrence of the alternative ammonia-oxidizing microbes such as anammox (anaerobic ammonia oxidation) bacteria (AMX) and ammonia-oxidizing archaea (AOA) in these systems. Based on total AOB numbers and the estimated cell density in the mixed liquor samples, AOB constituted 0.3 - 1.8% of the total bacterial population in the four WWTPs. Based on clone library, Nitrosomonas ureae-like AOB were dominant in plant A and B, while plant C and D had Nitrosomonas nitrosa-like AOB as major AOB group. The four different AMX primer sets targeting AMX 16S rRNA gene produced PCR amplicons distantly related to Chlamydia and Planctomycetales group bacteria. However, it was not clear these groups of bacteria perform anammox reaction in the SBR plants. Also, molecular evidence of AOA was found in one of the SBR plants, with a sequence located in the deep branch of the sediment creanarchaeota group.

• 한국물환경학회지
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• 제38권4호
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• pp.171-176
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• 2022

Recently, an autotrophic single-stage nitrogen removal (ASSNR) process based on the anaerobic ammonium oxidation (ANAMMOX) reaction has been proven as an economical ammonia treatment. It is highly evident that double-layered gel beads are a promising alternative to the natural biofilm for ASSNR because of the high mechanical strength of poly(vinyl alcohol) (PVA)/alginate structure and efficient protection of ANAMMOX bacteria from dissolved oxygen (DO) due to the thick outer layer. However, the thick outer layer results in severe mass transport limitation and consequent lowered bacterial activity. Therefore, the effects of the thickness of the outer layer on the overall reaction rate were tested in the biofilm model using AQUASIM for ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB) and ANAMMOX bacteria. A thickness of 0.5~1.0 mm is preferred for the maximum total nitrogen (TN) removal. In addition, a DO of 0.5 mg/L resulted in the best total nitrogen removal. A higher DO induces NOB activity and consequent lower TN removal efficiency. The optimal density of AO B and NO B density was 1~10% for a 10% ANAMMOX bacterial in the double-layered PVA/alginate gel beads. The real effects of operating parameters of the thickness of the outer layer, DO and concentrations of biomass balance should be intensively investigated in the controlled experiments in batch and continuous modes.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1230-1233
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• 2004

Ozone is useful oxidizing gas for the fabrication of oxide thin films. Accordingly researching on oxidizing gas is required. In order to obtain high quality oxide thin films, higher ozone concentration is necessary. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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• pp.110-113
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• 2005

Ozone is useful oxidizing gas for the fabrication of BSCCO thin films. In order to obtain high quality oxide BSCCO thin films, higher ozone concentration is necessary. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the Ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 제6회 학술대회 논문집 일렉트렛트 및 응용기술연구회
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• pp.35-38
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• 2004

Ozone is useful oxidizing gas for the fabrication of oxide thin films. Accordingly researching on oxidizing gas is required. In order to obtain high quality oxide thin films, higher ozone concentration is necessary. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the Ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.

• 대한환경공학회지
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• 제38권6호
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• pp.329-333
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• 2016

전기분해에 의한 소독은 소규모 하수처리장, 강우월류수, 선박평형수, 수영장, 양식장 등 염소의 운송, 보관, 사용에 어려움이 있는 곳에 활용될 가능성이 높다. 본 연구에서는 전압(2-5 V), 반응시간(1-10 min), 전해질농도(HCl 0.4-2.2% (w/v), NaCl 5-20 g/L)가 전기분해 산화제(HOCl, $O_3$, $H_2O_2$) 생성 효율에 미치는 영향을 고찰하였다. 회분식 실험 시 투입 전자 대비산화제 전환율(전류 효율)이 가장 높은 최적 조건은 HCl 2.2%, 3 V, 반응 시간 5분이었으며, 이 때의 전류 효율은 99.3%였다. HCl 2.2%, 3 V에서 수행한 연속식 전기분해실험에서는 전류 효율이 97.4% 이상이었으며, NaCl 농도(0-20 g/L) 증가에 따라 주요 산화제인 HOCl의 농도가 비례하여 증가하여 최대 99.8%의 결과를 보였다. 연속식 실험에서 얻은 전기분해수를 이용한 살균실험 결과 5분 안에 92.2% 이상의 총대장균군이 제거되어, 전기분해가 병원성 미생물 소독에 유효하게 사용될 수 있을 것으로 확인되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.138.2-138.2
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• 2013

Copper oxide is a multi-functional material being used in various research areas including catalysis, electrochemical materials, oxidizing agents etc. Among these areas, we have synthesized and utilized graphene based copper oxide nanocomposites (CuOx/Graphene) for the catalytic applications (C-N cross coupling reaction). Briefly, Cu precursors were anchored on the graphite oxide(GO) sheets being exfoliated and oxidized from graphite powder. Two different crystalline structures of Cu2O and CuO on graphene and GO were prepared by annealing them in Ar and O2 environments, respectively. The morphological and electronic structures were systemically investigated using FT-IR, XRD, XPS, XAFS, and TEM. Here, we demonstrate that the catalytic performance was found to depend on oxidative states and morphological structures of CuOx graphene nanocomposites. The relationship between the structure of copper oxides and catalytic efficiency toward C-N cross coupling reaction will be discussed.

• 융합정보논문지
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• 제11권9호
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• pp.109-114
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• 2021

유기공업 화학에서 알코올류의 산화제에 대해 연구가 많이 진행 되고 있으며, 그중에서도 크롬(VI)-계열의 시약들이 산화제로 널리 이용되어 왔다. 그리고 일차알코올을 알데히드로만 산화시키는 산화제와 메카니즘 규명이 필요하게 되었다. 이러한 연구의 일환으로 본 연구에서는 퀴놀린과 chromium(VI) trioxide을 반응시켜 크롬(VI)-퀴놀린 화합물[(C₉H₇NH)₂Cr₂O₇]을 합성하여, FT-IR 및 원소분석에서 구조를 확인하였다. 여러 가지 유기용매를 사용하여 크롬(VI)-퀴놀린 화합물에 의한 벤질 알코올의 산화반응은 유전상수 값이 큰 유기용매인 N,N'-dimethylformamide에서 높은 산화반응성을 보였다. N,N'-dimethylformamide 용매를 사용하여 크롬(VI)-퀴놀린 화합물은 치환 벤질 알코올류를 효율적으로 산화시켰고, Hammett 반응상수(ρ)=-0.69(303 K) 이였다. 본 실험에서 알코올의 산화반응 과정은 chromate ester 형성과정과, 속도결정단계에서 수소화 전이가 일어나는 반응경로임을 알 수 있었다. 결과적으로 크롬(VI)-퀴놀린 화합물은 벤질알코올, 알릴알코올, 일차알코올 및 이차알코올류를 알데히드나 케톤으로 전환시키는 효율적인 산화제로, 이차알코올류 존재 하에서 벤질알코올, 알릴알코올, 일차알코올의 선택적인 산화제로 사용할 수 있다.