Elimination efficiency of organic UV filters during ozonation and UV/H₂O₂ treatment of drinking water and wastewater effluent

Seo, Changdong,Shin, Jaedon,Lee, Minju,Lee, Woongbae,Yoom, Hoonsik,Son, Heejong,Jang, Seongho,Lee, Yunho Elsevier 2019 CHEMOSPHERE - Vol.230 No.-

<P><B>Abstract</B></P> <P>The efficiency of elimination of organic UV filters by ozonation and UV<SUB>254nm</SUB>/H<SUB>2</SUB>O<SUB>2</SUB> processes was assessed and predicted in simulated treatments of sewage-impaired drinking water and wastewater effluent in bench-scale experiments. Second-order rate constants (<I>k</I>) for the reactions of the eight UV filters with ozone and OH were determined by quantum chemical calculations and competition kinetics methods, respectively. The UV filters containing phenolic (ethylhexyl-salicylate, homosalate, and benzophenone-3) and olefinic moieties (4-methylbenzylidene-camphor, benzyl-cinnamate, and 2-ethylhexyl-4-methoxycinnamate) showed high ozone reactivity (<I>k</I> ≥ 8 × 10<SUP>4</SUP> M<SUP>−1</SUP>s<SUP>−1</SUP> at pH 7), while those without such electron-rich moieties (isoamyl-benzoate and benzophenone) were ozone-refractory. All the UV filters showed high OH reactivity (<I>k</I> ≥ 6.2 × 10<SUP>9</SUP> M<SUP>−1</SUP>s<SUP>−1</SUP>). In concordance with the rate constant information, the phenolic and olefinic UV filters were efficiently eliminated by ozone treatment, requiring specific ozone doses of <0.5 mgO<SUB>3</SUB>/mgDOC for ∼100% elimination. The UV filters were eliminated by ≤ 38% at a UV fluence of 1500 mJ/cm<SUP>2</SUP> in the UV<SUB>254nm</SUB>-only treatment. Rapid photoisomerisation between the <I>E</I> and <I>Z</I> geometric isomers was observed for the olefinic UV filter, benzyl-cinnamate. The addition of H<SUB>2</SUB>O<SUB>2</SUB> (10 mg/L) greatly enhanced the elimination of all UV filters, indicating that OH was the main contributor to their elimination in the UV<SUB>254nm</SUB>/H<SUB>2</SUB>O<SUB>2</SUB> treatment. A chemical kinetics approach developed previously for ozonation and UV/H<SUB>2</SUB>O<SUB>2</SUB> processes was shown to predict the elimination of the UV filters in the tested water matrices reasonably well, demonstrating that the chemical kinetics method can be used for a priori prediction of micropollutant elimination in oxidative treatment processes for potable reuse of municipal wastewater effluents.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Reaction kinetics were determined for ozone, .OH, and UV<SUB>254nm</SUB> with organic UV filters </LI> <LI> Phenolic & olefinic UV filters show high ozone reactivity and efficient elimination. </LI> <LI> Rapid photo-isomerisation occurs for the olefinic UV filters. </LI> <LI> .OH is mainly responsible for the elimination of UV filters in UV<SUB>254nm</SUB>/H<SUB>2</SUB>O<SUB>2</SUB> treatment </LI> <LI> The chemical kinetics method allows a priori prediction of micropollutant elimination. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

치아측색을 위한 스마트폰용 광학장치 설계

이창동(Changdong Lee),정진형(Jin-Hyoung Jeong),이상식(Sangsik Lee) 대한전기학회 2016 대한전기학회 학술대회 논문집 Vol.2016 No.2

스마트폰을 이용한 측색의 경우 기종별로 다른 센서(카메라)와 조명 등 측정 환경의 통제가 필수적이다. 본 연구에서는 임의의 표준색상을 선정하여 다양한 광학계를 적용하여 표준색상과의 색차를 비교함으로써 가장 색차를 최소화 시킬 수 있는 광학계의 구조를 제안한다.

Nitrogen Oxides, Particulate Nitrate, and Refractory Black Carbon in Urban Seoul during the Early Winter GMAP Campaign

Hyunmin Lee,Junsu Gil,Saehee Lim,Meehye Lee,Changdong Yoon,Min-Suk Bae,Moonsu Park 한국대기환경학회 2022 한국대기환경학회 학술대회논문집 Vol.2022 No.10

원자력 이슈에 대한 정부와 언론의 커뮤니케이션 전략 비교연구: 토픽모델링(Topic Modeling)의 적용

이태준 ( Taejun (david) Lee ),이승배 ( Seungbae Lee ),오창동 ( Changdong Oh ) 한국지역언론학회 2017 언론과학연구 Vol.17 No.3

이 연구는 원자력 거버넌스의 핵심 행위자로써 정부와 언론의 커뮤니케이션 행태를 비교, 분석하기 위해 정부(혹은 원자력계)의 보도자료와 언론사의 보도기사에 사용된 원자력 이슈프레임이 원자력 거버넌스의 주요 정책현안 및 사건사고가 발생하는 과정에서 나타난 변화를 비교, 분석하였다. 이를 위해 2014년 1월부터 2016년 12월까지 3년간, 정부 측 보도 자료와 언론사 전체의 보도기사 총 30,490건을 토픽모델링(Topic Modeling)기법을 활용하여 수집, 분석한 후, 주요 원자력 이슈 프레임을 산업경제/환경안전/정책거버넌스/외교안보 4가지로 분류하여 시점별로 이슈 프레임의 변화추이와 세부적인 양태를 비교·분석 하였다. 연구결과, 원자력 정책을 둘러싼 정부행위자와 언론매체의 정책이슈에 대한 전략적 이슈관리 커뮤니케이션 행태 변화를 통해 몇 가지 시사점을 얻을 수 있다. 구체적으로 원자력계 내부에서와 언론사별로 각기 다른 이슈관리 전략을 구사하였으며, 원자력계 내부에서 강조하려고 했던 이슈프레임과 언론사에서 주로 다루었던 이슈프레임간 일치성과 공통점이 매우 낮은 것으로 나타났다. 이러한 결과는 정책효과, 정부신뢰, 갈등관리 차원에서 원자력 거버넌스의 질을 결정하는 핵심 행위자인 정부와 언론이 원자력 이슈에 대한 사회적 공론화, 공공의제 설정, 여론 형성, 정책결정과정에 대해 상이한 관점과 행태를 보인 것을 실증적으로 보여준다. The objective of this study is to compare strategic issue management and communicative action between government organizations and media with respect to nuclear energy. To this end, this paper investigates predominant issue frames of nuclear energy presented in the press releases and news articles according to the major trends and notable changes of the public governance and affairs related to nuclear energy, especially for 2015-2017. By collecting and analyzing a total of 30,490 texts in government organizations` press releases and news media texts based on topic modeling, the current reveals that government organizations and media displayed a proclivity for selecting particular frames regarding nuclear energy issues and very different characteristics of strategically managing public agendas and policy issues during the same time period. It is discussed how the results will facilitate a deeper appreciation of how they could be used to build and maintain the quality of collaborative governance among key policy actors (i.e., governments vs. media) and what communication strategies would be more feasible and desirable in designing and implementing the process of agenda-setting, sense-making, consensus- building, decision-making and problem-solving with respect to nuclear energy through government communication and media discourse.

인공 슬관절 전치환술에서 두가지 슬개삽입물의 비교

한창동(Changdong Han),김형규(Hyunggyu Kim),이우석(Woosuk Lee) 대한슬관절학회 1998 대한슬관절학회지 Vol.10 No.2

The displacement of patellar components, such as dislocation or subluxation, causes polyethylene wear and further induces metallosis of the metal-backed patella. We compared two different patellar components, onset(Miller-Galante I) and inset(Whiteside-Ortholoc I)type, to understand the differences in patellar tracking according to their designs. Patellar prosthesis position in 43 primary total knee arthroplasties was evaluated with patellar tilt, patellar displacement from the center of the trochlear groove, medial placement, patellar thickness, and joint line height. For the MG(Miller-Galante I)group, the patellar displacement was laterally 50.0% and for the Ortholoc group, it was 33.3%. In the MG group, 4 cases of revision of the patellar component due to excessive polyethylene wear were performed, but there was no excessive wear of polyethylene in Ortholoc group. One of the primary factors which influence tracking of the patellofemoral joint is the difference in design between the patellar component and the femoral component. But in the opinion of the authors, the slope or lateral displacement of the patellar component have no correlation with each other under radiological measurements. However, the inset-type patellar component is a design that maintains the bony flange within the lateral flange, therefore relieving the shear stress and rotational forces loaded on the patellofemoral joint and protecting the metal-backing from exposure. Thereby, even if dislocation or subluxation of the patellar component should occur, polyethylene wear or metallosis caused by excessive wearing can be minimal.

파노라마루프 모터 개수 축소 방안 연구

이호열(Horyul Lee),서승우(Seungwoo Seo),김창동(Changdong Kim),정진상(Jinsang Jung),윤창진(Changjin Yoon),임주훈(Juhoon Lim) 한국자동차공학회 2013 한국자동차공학회 학술대회 및 전시회 Vol.2013 No.11

LLaVA를 활용한 분포 외 데이터 탐지

이영환(YoungHwan Lee),유창동(ChangDong Yoo) 대한전자공학회 2024 대한전자공학회 학술대회 Vol.2024 No.6

In this paper, we introduce LLaVA-OOD, an Out-of-Distribution (OOD) detection method using pre-trained Multimodal Large Language Models (MLLMs). This method employs the pretrained LLaVA model for a convenient and scalable OOD detection strategy without a training phase. LLaVA-OOD uses simple prompt to detect and classify in-distribution data effectively in a zero-shot setting. Our experiments on the MNIST dataset highlight the practicality and scalability of our approach for OOD detection. We suggest that further refinements, such as more sophisticated prompt designs or the incorporation of additional specialized models, could indicate directions for future research and development.

S-383 Inhibition of Neutrophil Elastase Contributes to Attenuation of LPS-Induced Acute Lung Injury

( Jongmin Yun ),( Changdong Yeo ),( Chinkook Rhee ),( Inkyoung Kim ),( Donggun Lee ),( Sanghaak Lee ),( Jinwoo Kim ) 대한내과학회 2016 대한내과학회 추계학술발표논문집 Vol.2016 No.1

Aim of the study: Patients in whom neutropenia recovery is complicated by pneumonia have an increased risk of acute lung injury (ALI) and detrimental outcomes. The aim of the present study was to investigate whether inhibition of neutrophil elastase (NE) is effective in lipopolysaccharide (LPS)-induced ALI during neutropenia recovery in a murine model, and whether it upregulates the activation of the Mer signaling pathway. Materials and Methods: Cyclophosphamide was given to mice to induce neutropenia. Seven days later, they were administrated LPS intratracheal instillation. Sivelestat, a neutrophil elastase inhibitor, was given by intraperitoneal injection once daily starting on day 0 and continuing until mice were sacrificed on day 5 (preventive group). Alternatively, sivelestat was given after, instead of before, LPS administration on day 2 (therapeutic group). Results: Sivelestat attenuated the lung edema and histopathological changes associated with LPS-induced lung injury. The accumulation of neutrophils and the concentrations of TNF-α, IL-6 and MPO in bronchoalveolar lavage (BAL) fluids were inhibited effectively by sivelestat. The expression of ICAM-1 and NF-κB p65 were also reduced after sivelestat administration. The protein and gene expression of MerTK tended to increase with sivelestat treatment. Conclusions: Sivelestat significantly attenuated LPS-induced ALI during the recovery of neutropenia. These findings suggest that NE inhibition could be a promising means of alleviating lung inflammation without increasing susceptibility to infection in ALI/ARDS during neutropenia recovery.

새만금 경축순환 농업 예정 부지의 토양 염류도 경시변화

이승헌 ( Seungheon Lee ),김영일 ( Youngil Kim ),홍병덕 ( Byeongdeok Hong ),김순근 ( Soonkeun Kim ),남창동 ( Changdong Name ),김병기 ( Byeongki Kim ) 한국농공학회 2010 한국농공학회 학술대회초록집 Vol.2010 No.-

농업부문의 급속한 시장개방에 능동적인 대처와 국내 축산업의 경쟁력 제고를 위한 새로운 대안으로 대규모 간척지를 활용한 경종·축산·환경이 공존하는 자연순환형 친환경농업단지 조성 필요성이 증대되고 있다. 새만금 간척 농지에 경축순환 농업을 도입하기 위해서는 장차 내부 개발 예정지구내의 토양특성을 파악하는 것이 중요하다. 조사구간은 새만금간척지구 내의 경축순환 농업 예정지 304ha로 영자리가 남아있는 0~2%정도의 경사를 가진 하해혼성충적층을 모재로 평탄지에 위치하고 있다. 토양 시료는 지구내 200×200m로 구획 후 GPS에 좌표 입력하여 관리수위 위에 노출된 위치에서 채취하여 각 지점에서 0~20cm, 20~50cm깊이로 2점씩 총 168점을 2009년도와 2010년도에 2차례 채취하여 포화침출법에 의한 토양전기전도도를 측정하여 토양염도의 경시적인 변화를 관찰 하였다. 측정결과 방조제 체절이후 해수가 유통되고 있어 제염이 이루어 지지 않아 토양 포화침출액의 전기전도도는 매우 높은 상태였다. 2009년도 조사결과 표토 포화침출액의 평균은 28.6 dS/m, 심토 포화침출액의 평균은 24.4 dS/m였다. 일부 지점에서는 표토가 심토보다 높은 특징을 보였고 조사지역의 표고와 토성 등의 불균질성이 반영되어 표토 포화침출액의 전기전도도의 분포는 0.8 dS/m ~ 84.7 dS/m였고 심토는 0.9 dS/m~ 44.1 dS/m였다. 2010년도 조사결과에서도 유사한 경향을 보였는데, 표토 포화침출액의 평균은 28.0 dS/m, 심토 포화침출액의 30.4 dS/m였다. 또한 표토 포화침출액의 전기전도도의 분포는 0.3 dS/m ~ 137.4 dS/m였고 심토는 1.0 dS/m ~ 154.4 dS/m였다. 2009년과 2010년의 자료를 비교하여 보면 표토의 경우 거의 유사한 값을 보였고 심토의 경우 약간 증가하였다. 방수제 착공과 담수화 진행 및 수위조절을 통해 완전 노출이 이루어지면 세부 실시설계 및 영농계획 수립을 위해서는 추가적인 이화학성 조사가 필요할 것으로 판단되며 특히 상대적으로 높은 표고에 위치하여 염류가 집적된 지점을 개발할 경우에는 특별한 대책이 요구된다.

폐광산 지하 채굴적 파악을 위한 탄성전기탐사법 적용 연구

이동원(Dongwon Lee),홍창동(Changdong Hong),민경남(Kyungnam Min),안광국(Kwangkuk Ahn) 한국지반환경공학회 2015 한국지반환경공학회 학술발표회논문집 Vol.2015 No.09