영가철에 의한 과황산의 활성화 및 유기물질의 산화분해

권희원 ( Hee-won Kwon ),김지은 ( Jee-eun Kim ),김영훈 ( Young-hun Kim ) 한국환경기술학회 2015 한국환경기술학회지 Vol.16 No.1

과황산은 원위치 화학적 산화공법에서 가장 많이 사용되는 산화제 중의 하나로 토양 · 지하수환경 에서 높은 안정성과 산화력이 장점이다. 과황산은 그 자체로 산화력이 있으나 활성화되어 라디칼을 형성할 경우 산화력이 증대된다. 자외선, 열, 염기 등을 이용한 활성화 방법이 있으나 이들 방법은 토양환경에서 사용이 불가능하거나 제한적으로 사용될 수 있다. 본 연구에서는 영가철을 사용하여 환원적 활성화를 시도하였다. 영가철은 기존의 투수성 반응벽체의 반응물질로 사용되고 있는 비교적 친환경적 환원제이다. 영가철은 과황산을 성공적으로 활성화시키며 모델오염물질인 나이트로벤젠을 분해하였다. 과황산의 농도를 증가시키면 분해반응 속도도 증가되고 과황산의 농도를 고정한 다음 철의 주입량을 증가시켜도 반응속도를 조절할 수 있음을 증명하였다. Persulfate is one of the popular oxidants which can be used for in-situ chemical oxidation (ISCO) since it has moderate stability in soil and groundwater environment and relatively strong oxidation power through activation. The common activation methods such as UV, heat, and base cannot be applied or have limitations in soil environment. Current study tested a reductive activation of persulfate using zero-valent iron (ZVI) which has been used for permeable reactive barrier. ZVI successfully activated persulfate and oxidized a model target organic contaminant, nitrobenzene. Increased persulfate concentration led to an increased reaction rate up to a point and the degradation rate was not increased from the point. The increased dose of ZVI also increased the reaction rate at a fixed dose of persulfate indicating the dose of activator is one of the factor controling the reaction rate.

사회초년생이 된 입학사정관전형 입학생의 진로발달과정에 대한 내러티브 탐구: 프로티언 경력 태도를 토대로

권희원(Kwon, Hee-won) 이화여자대학교 교육과학연구소 2020 교육과학연구 Vol.51 No.1

본 연구의 목적은 구성주의 관점에서 사회초년생이 된 입학사정관전형 입학생의 진로발달과정을 탐구하는 것이다. 청소년 시절 자기 주도적으로 진로를 탐색하였고, 그 과정을 인정받아 대학에 입학하였으며, 이후에도 여전히 주체적으로 진로를 나아가고 있는 이들로 연구참여자를 선정하였다. 이들의 삶의 맥락에서 진로가 어떻게 구성되었는지, 진로발달과정의 의미는 무엇인지 Clandinin과 Connelly의 내러티브 탐구를 활용하여 연구를 수행하였다. 과거, 현재, 미래로 연결되는 총체적 삶의 맥락에서 진로발달과정을 조망하고, 이들에게 나타나는 프로티언 경력 태도에 주목하였다. 연구결과, 자신을 이야기하며 생애주제를 찾고, 풍부한 경험 자본을 바탕으로 환경에 대한 유연성을 고양시킬 수 있었던 경험이 곧 프로티언 경력 태도 함양으로 연결될 수 있음을 밝혀낼 수 있었다. 생애주제를 통한 명확한 자기 인식과 높은 환경적응성은 자기 주도적, 가치 지향적 태도로 연결될 수 있었고, 프로티언 경력 태도를 지닌 이 시대의 인재로 성장할 수 있게 하였다. 이에 본 연구에서는 진로발달과정의 의미를 탐구하여 교육적 시사점을 제시하였다. The purpose of this study was to investigate the career development process of new entrants to the workforce selected by the Admission Officer System from the perspective of career competencies. The research questions of this study are as follows: First, how is career development situated in the context of the students’ lives, who were selected in their early years in the Admission Officer System, when they first entered the workforce? Second, what can be implied from those students’ career paths? This study used Clandinin and Connelly"s narrative inquiry method to describe the career experiences of the students from their early years in the Admission Officer System. Based on the study results, the experiences of students talking about themselves and finding life themes were found to enhance their flexibility in career choices based on the capital of abundant experience. These experiences lead to the cultivation of a protean career attitude. Therefore, we can understand the necessity of discussing education and career from the perspective of life design. Educational implications were suggested based on the results of this study.

생태계 기반 어업평가의 위험도 추정에 관한 개선연구

박희원 ( Hee Won Park ),장창익 ( Chang Ik Zhang ),권유정 ( You Jung Kwon ),서영일 ( Young Il Seo ),오택윤 ( Taeg Yun Oh ) 한국어업기술학회 2013 수산해양기술연구 Vol.49 No.4

This study identified problems of the existing ecosystem-based fisheries assessment approach, and suggested new methods for scoring risk and for the estimation of fishery risk index. First, risk scores of zero to two for target and limit reference points for each indicator were replaced by those of zero to three, and the risk scores were calculated from new formulae which were developed in this study. Second, a new method for estimating fishery risk index (FRI) was developed in this study, considering the level of indicators. New method was applied to the Korean large purse seine fishery, large pair trawl fishery and drag net fishery. More precise and detailed risk scores were obtained from the new method, which can explain the risks by the wider range of both risk levels for ``better than target`` and ``beyond limit``. The new method for estimating FRI could avoid the basic problem related with duplicated computations of fishery-level indicators, which improved the estimated FRI to be more accurate. Also, a method for estimating variance of FRI using the bootstrap was proposed in this study.

환원-산화 연계처리를 통한 니트로벤젠의 반응성 향상 및 무해화 연구

권희원,황인성,김영훈,Kwon, Hee-Won,Hwang, Inseong,Kim, Young-Hun 한국환경과학회 2020 한국환경과학회지 Vol.29 No.12

In this study, the applicability of reduction-oxidation-linked treatment was evaluated for nitrobenzene and a by-product by analyzing the reaction kinetics. Nitrobenzene showed very low reactivity to persulfate that was activated using various methods. Nitrobenzene effectively reacted through the reduction process using Zero-Valent Iron (ZVI). However, aniline, a toxic substance, was produced as a by-product. Reduction-oxidation-linked treatment is a method that can allow the oxidative degradation of aniline after reducing nitrobenzene to aniline. The experimental results show improved reactivity and complete decomposition of the by-product. Improved reactivity and decomposition of the by-product were observed even under conditions in which the reduction-oxidation reaction was induced simultaneously. No activator was injected for persulfate activation in the process of reducing oxidant linkage, and the activation reaction was induced by ferrous iron eluted from the ZVI. This indicates that this method can be implemented relatively simply.

생쥐배아의 냉동보존에 있어서 여러 조건의 평가 - 저속 처리단계와 급속 처리단계, 배양액, 세포기

이승연,권주택,송희원,조윤희,이기숙,류철희,김종덕,Yi, Seung-Yeun,Kwon, Ju-Taek,Song, Hee-Won,Cho, Yun-Hee,Lee, Ky-Sook,Rheu, Cheul-Hee,Kim, Jong-Duk 대한생식의학회 1999 Clinical and Experimental Reproductive Medicine Vol.26 No.2

Cryopreservation is able to store the surplus pre-embryos for freezing and furthermore thawing and transfer in a subsequent cycle. Cryopreserving cells which are maintaining their viability are the very complex process. This study has been carried out in order to find the effects of cryopreservation steps, freezing media and embryonic stages on the rates of viability and development of cryopreserved mouse embryos. Female ICR mice ($6{\sim}8$ weeks old) were induced to superovulate by sequential intraperitoneal injection of 5 IU PMSG and 5 IU hCG 48h apart. Mouse embryos were collected according to its developmental stage after the injection of hCG. Embryos were cryopreserved not only by cryoprotectant step (1 step${\sim}$4 step) but also in a variety of media (HTF, IVF medium, D-PBS) and cell stage. The results were as follows: There is no clear advantage in these freezing media of rapid method, but 4 cell and 8 cell of slow method (2, 3, 4 step) have advantage in D-PBS. The development of embryos according to cell stage become greater in 8 cell stage. In the treatment steps of cryopreservation, the development of embryo to blastocyst was similar among rapid method, but the development of 4 cell and 8 cell embryos to blastocyst according to slow method was better than rapid method.

열적활성화된 과황산에 의한 염화페놀의 산화분해특성 연구

손지민,권희원,황인성,김정진,김영훈,Son, JiMin,Kwon, Hee-Won,Hwang, Inseong,Kim, Jeong-Jin,Kim, Young-Hun 한국환경과학회 2020 한국환경과학회지 Vol.29 No.1

Oxidative degradation of phenol, three monochlorophenols (2-chlorophenol, 2-CP; 3-chlorophenol, 3-CP; 4-chlorophenol, 4-CP), four dichlorophenols (2,3-dichlorophenol, 2,3-DCP; 2,4-dichlorophenol, 2,4-DCP; 2,5-dichlorophenol, 2,5-DCP; 2,6-dichlorophenol, 2,6-DCP), and two trichlorophenols (2,4,5-trichlorophenol, 2,4,5-TCP; 2,4,6-trichlorophenol, 2,4,6-TCP) was conducted with heat activated persulfate. As the number of chlorinations increased, the reaction rate also increased. The reaction rate was relatively well fitted to the zero-order kinetic model, rather than the pseudo-first order kinetic model for the reactions at 60 ℃, which can be explained by insufficient activation of the persulfate at 60 ℃, and the oxidation reaction of 2,4,6-TCP at 70 ℃ was relatively well fitted to the pseudo-first order kinetic model. The oxidation reaction rate generally increased with increase of persulfate concentration in the solution. 2,6-dichloro-2,5-cyclohexadiene-1,4-dione was found as a degradation product in a GC/MS analysis. This compound is a non-aromatic compound, and one chlorine was removed. This result is similar to the result of previous studies. The current study proved that heat activated persulfate activation could be an alternative remediation technology for phenol and chlorophenols in soil and groundwater.

과황산의 열적활성화 및 염소계용제의 산화분해

장하이롱 ( Hailong Zhang ),권희원 ( Hee-won Kwon ),최정학 ( Jeong-hak Choi ),김영훈 ( Young-hun Kim ) 한국환경과학회 2017 한국환경과학회지 Vol.26 No.11

Oxidative degradation of chlorinated ethenes was carried out using heat-activated persulfate. The activation rate of persulfate was dependent on the temperature and the activation reaction rate could be explained based on the Arrhenius equation. The activation energy of persulfate was 19.3 kcal/mol under the assumption that the reaction between the sulfate radical and tricholoroethene (TCE) is very fast. Activation could be achieved at a moderate temperature, so that the adverse effects due to high temperature in the soil environment were mitigated. The reaction rate of TCE was directly proportional to the concentration of persulfate, indicating that the remediation rate can be controlled by the concentration of the injected persulfate. The solution was acidized after the oxidation, and this was dependent on the oxidation temperature. The consumption rate of persulfate was high in the presence of the target organic, but the self-decomposition rate became very low as the target was completely removed.

국내시판 시멘트의 6가 크롬 용출량에 대한 연구

하태욱 ( Tae-wook Ha ),권희원 ( Hee-won Kwon ),김영훈 ( Young-hun Kim ) 한국환경기술학회 2012 한국환경기술학회지 Vol.13 No.1

인간의 생활과 밀접하게 관계하고 있는 시멘트는 토목·건설재료로서 매우 큰 이점을 가진다. 그러나 시멘트로부터 용출될 수 있는 크롬과 납, 니켈, 그리고 코발트 등 미량의 중금속은 인체에 위해성을 가지므로 시멘트의 환경영향을 고려하여야 한다. 본 연구에서는 현재 국내에 시판중인 포틀랜드 시멘트 3종의 제품을 선정하여 일본시멘트협회 시험법을 이용하여 6가 크롬 용출량을 조사하였다. 그 결과, 각각의 제품에서 9.2, 8.6, 8.4 mg/kg의 6가 크롬이 용출되었다. 시멘트는 고형화 과정에서 수화물을 형성하며 중금속을 고정화하는 것으로 알려져 있으나 고형화 된 시멘트의 6가 크롬 용출량을 조사한 결과, 각각의 제품에서 4.6, 3.1, 2.9 mg/kg이 용출되었으며, 미국 TCLP법으로 용출 실험한 경우 각각의 제품에서 3.9, 4.9, 4.0 mg/kg이 용출되었다. 시멘트에서 용출되는 6가 크롬을 저감하기 위해 환원제로 2가 철을 주입하여 용출 실험을 수행하였다. 그 결과 상당한 6가 크롬 용출 저감효과를 확인하였으며, 고형화 단계에서 2가 철을 주입한 경우에도 상당한 6가 크롬 용출 저감 효과를 나타내었다. Cement is closely related to human life, and it has a lot of advantages as a construction material. But trace heavy metals that has toxicity such as chromium, lead, nickel, and cobalt can be leached from cement. In this study, hexavalent chromium leaching test was performed using the 3 kind of commercial cement products which being sold in domestic market. And leaching test was conducted following the Japan Cement Association leaching method (JCAS I-51). As a result, leached hexavalent chromium from products was 8.4-9.2 mg/kg. After solidification, the leached concentration was ranged from 2.9 to 4.6 mg/kg. Result of leaching test by TCLP showed the range of 3.9-4.9 mg/kg. Ferrous iron as a reductant was injected for reducing hexavalent chromium that leached from cement. Significant reduction in hexavalent chromium leaching was obtained upon the ferrous iron injection before cement solidification.

드론을 이용한 낙석 위험지역 평가

김동규(Dong-Kyu Kim),권남훈(Nam-Hoon Kwon),이수현(Soo-Hyun Lee),최희원(Hee-Won Choi),정영현(Young H. Jeong),박상철(Sang C. Park) (사)한국CDE학회 2016 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2016 No.동계

In Korea, the accident caused by falling-stone has been occured frequently. These days we do the periodic inspections to prevent the accidents, but we only can get subjective information such as slope and discontinuity. Our goal of this project is measuring that things using dorne with 3D scanner to get objective information so that evaluate safety more accurately.

SUV 후석 토션바 백 리클라이닝 시스템 최적화

이성용(LEE SUNG YOUNG),권희원(KWON HEE WON),박태규(PARK TAE KUE) 대한기계학회 2022 대한기계학회 춘추학술대회 Vol.2022 No.6