폐기물 처리시설로부터 수은의 배출 특성과 물질흐름분석 연구

장용철,김홍경,이가인,이승훈,홍용석 한국폐기물자원순환학회 2020 한국폐기물자원순환학회지 Vol.37 No.5

Mercury is one of toxic heavy metals and a persistent pollutant of global concern that is regulated by the MinamataConvention in 2017 August. There is a need for carefully identify mercury levels in waste streams and properly treatand manage the waste, if significant amount of the metal exists. In this study, mercury in waste materials and byproducts(112 samples) from treatment processes from a fluorescent lamp recycling facility as well as industrial and medicalincineration facilities was measured. Substance flow analysis (SFA) of mercury was performed on the recycling andincineration facilities. Other relevant data such as sludge generation, chemical addition, and wastewater treatment rateswere obtained through the field investigations, literature review from available reports and statistics. Data reconciliationwith material flow analysis Software STAN 2.5 was employed for mercury flow in each process by decreasing data errorand by adopting least square method and error propagation theory. Based on the results of SFA, it was found that majorflow of mercury at wastewater treatment facilities is attributed to the sludge during the treatment processes. As a resultof this study, it was found that mercury flow from the fluorescent lamp recycling facility was estimated to be approximately499 g/day (equivalent to 175 kg/yr), mainly from adsorption treatment (activated carbon filter) process as well as thecondensate and phosphor powder. In the industrial incineration facility, air emission of mercury was estimated to be 21.4g/day (equivalent to 7.8 kg/yr), followed by bottom ash (8.7 g/day) and sludge (5.9 g/day), while the medical wasteincineration process mainly generated mercury in fly ash (22.8 g/day) and wastewater (25.3 g/day). Detailed examinationof more diverse waste treatment facilities is still needed to eliminate unidentified mercury streams from the waste treatmentfacilities.

연극인 대상 희곡읽기 모임 운영 사례

장용철 공연과이론을위한모임 2017 공연과 이론 Vol.- No.67

한국 플라스틱의 물질흐름분석과 순환경제 구축 전략

장용철 한국폐기물자원순환학회 2023 한국폐기물자원순환학회 심포지움 Vol.2023 No.1

저항성 운동이 알츠하이머 형질전환 생쥐 뇌의 베타 아밀로이드 대사와 인지기능에 미치는 영향

장용철,구정훈 한국응용과학기술학회 2020 한국응용과학기술학회지 Vol.37 No.3

The aim of this study was to investigate the effect of resistance exercise(RE) on betaamyloid(Aβ) metabolism, neuronal cell death, and cognitive function in the transgenic mice model of Alzheimer's disease(AD). Fourteen transgenic(tg) mice and fourteen nontransgenic(nontg) mice were divided into four groups: (1)nontgcontrol(NTC, n=7) (2)nontgRE(NTRE, n=7) (3)tgcontrol(TC, n=7), and (4)tgRE(TRE, n=7). The groups with RE were performed to progressive RE on ladder equipment for 8 weeks. The groups with RE were performed to progressive RE on ladder equipment for 8 weeks. After then, the cognitive function was measured by using the water maze test ,and Aβ metabolismrelated proteins, neuronal cell death, and SIRT1/PGC1α pathway were also measured. Here, we found escape latency and time were significantly increased in the TC compared to the NTC group, but it was significantly reduced in the TRE group, indicating RE may ameliorate cognitive dysfunction. Next, we found an increased in Aβ protein of TC compared to NTC, but it was significantly reduced in the TRE group following RE. In neuronal cell death, Bcl2 was also significantly decreased and Bax was significantly increased in the TC compared to the NTC group, but RE can increase Bcl2 and reduce Bax, which may elevate the ratio of Bcl2/Bax. We further found a decrease in the level of ADAM10 and RARβ protein was significantly increased whereas increased in ROCK1 and BACE1 expression level was significantly reduced following RE in the TRE compared to the TC group. In addition, the level of SIRT1/PGC1α proteins was decreased in the TC group compared to NTC group, but, these markers were significantly increased in the TRE group following RE. Therefore, our finding indicated that RE may ameliorate cognitive deficits by reducing Aβ protein and neuronal cell death via regulating SIRT1/PGC1α, amyloidogenic pathway, and nonamyloidogenic pathway, which may play a role in an effective strategy for AD. 본 연구는 알츠하이머(Alzheimer’s disease: AD) 형질전환 생쥐를 대상으로 저항성 운동 (resistance exercise: RE)이 해마의 베타 아밀로이드(βamyloid: Aβ) 단백질 대사, 신경세포사멸 및 인지기능에 미치는 영향을 확인하는데 목적이 있다. AD 비 형질전환 생쥐(nontransgenic: nontg, n=14) 와 형질전환 생쥐(transgenic: Tg, n=14)를 무선 배정하여 비 형질전환 생쥐 대조군 (nontgcontrol: NTC, n=7), 비 형질전환 생쥐 저항성 운동군(nontgRE: NTRE, n=7), 형질전환 대조군(tgcontrol: TC, n=7) 및 형질전환 저항성 운동군(tgRE: TRE, n=7)으로 구분하였다. RE는 특수 제작한 사다리 저항성 운동 기구를 사용하여 점진적으로 set 수를 증가시켜 총 8주간 실시하였다. 운동 후 인지기능 능력을 평가하기 위한 수중미로검사와 Aβ 단백질 대사, 신경세포사멸 지표 및 SIRT1/PGC1α 단백질 발현 수준을 확인하였다. 수중미로검사 결과 거리와 시간 모두 TC 집단에서 유의하게 증가 되었지만 RE를 실시한 TRE 집단에서 거리와 시간이 감소 되어 인지능력이 개선된 것으로 확인되었다. 또한, TC 집단에서 증가된 Aβ 단백질 발현은 RE를 통해 감소하는 것으로 나타났다. 신경세포사멸 관련 단백질인 Bcl2/Bax ratio는 TC 집단에서 유의하게 감소되어 신경세포사멸이 증가 된 것으로 나타났지만 RE는 Bcl2/Bax ratio을 증가시켜 신경세포사멸을 감소시킨 것으로 확인되었다. TC 집단에서 증가된 BACE1 및 ROCK1 과 감소된 ADAM10과 RARβ 단백질 발현은 RE를 통해 감소되거나 증가 된 것으로 나타났고, SIRT1/ PGC1α 단백질 발현은 TC 집단에서 감소 되었지만 RE를 통해 증가 된 것으로 나타났다. 따라서 8주간의 RE는 AD의 병리학적 특징인 Aβ 단백질 발현을 감소시키고 관련 생성 기전들을 조절하여 (SIRT1/PGC1α 기전 활성, 아밀로이드 생성기전 억제, 비아밀로이드 생성기전 활성) 신경세포사멸 억제시키고 결과적으로 인지기능을 개선 시킬 수 있는 효과적인 운동 방법이라고 생각된다.

북녘의 문화재 톺아보기 ②

장용철 북한연구소 2020 北韓 Vol.- No.585

Characteristics of Dissimilatory Arsenate-reducing Bacteria

장용철,다까미자와 카즈히로,조훈,키쿠치 신타로,Chang, Young-Cheol,Takamizawa, Kazuhiro,Cho, Hoon,Kikuchi, Shintaro The Korean Society for Biotechnology and Bioengine 2012 KSBB Journal Vol.5 No.4

Although, microbial arsenic mobilization by dissimilatory arsenate-reducing bacteria (DARB) and the practical use to the removal technology of arsenic from contaminated soil are expected, most previous research mainly has been focused on the geochemical circulation of arsenic. Therefore, in this review we summarized the previously reported DARB to grasp the characteristic for bioremediation of arsenic. Evidence of microbial growth on arsenate is presented based on isolate analyses, after which a summary of the physiology of the following arsenate-respiring bacteria is provided: Chrysiogenes arsenatis strain BAL-$1^T$, Sulfurospirillum barnesii, Desulfotomaculum strain Ben-RB, Desulfotomaculum auripigmentum strains OREX-4, GFAJ-1, Bacillus sp., Desulfitobacterium hafniense DCB-$2^T$, strain SES-3, Citrobacter sp. (TSA-1 and NC-1), Sulfurospirillum arsenophilum sp. nov., Shewanella sp., Chrysiogenes arsenatis BAL-$1^T$, Deferribacter desulfuricans. Among the DARB, Citrobacter sp. NC-1 is superior to other dissimilatory arsenate-reducing bacteria with respect to arsenate reduction, particularly at high concentrations as high as 60 mM. A gram-negative anaerobic bacterium, Citrobacter sp. NC-1, which was isolated from arsenic contaminated soil, can grow on glucose as an electron donor and arsenate as an electron acceptor. Strain NC-1 rapidly reduced arsenate at 5 mM to arsenite with concomitant cell growth, indicating that arsenate can act as the terminal electron acceptor for anaerobic respiration (dissimilatory arsenate reduction). To characterize the reductase systems in strain NC-1, arsenate and nitrate reduction activities were investigated with washed-cell suspensions and crude cell extracts from cells grown on arsenate or nitrate. These reductase activities were induced individually by the two electron acceptors. Tungstate, which is a typical inhibitory antagonist of molybdenum containing dissimilatory reductases, strongly inhibited the reduction of arsenate and nitrate in anaerobic growth cultures. These results suggest that strain NC-1 catalyzes the reduction of arsenate and nitrate by distinct terminal reductases containing a molybdenum cofactor. This may be advantageous during bioremediation processes where both contaminants are present. Moreover, a brief explanation of arsenic extraction from a model soil artificially contaminated with As (V) using a novel DARB (Citrobacter sp. NC-1) is given in this article. We conclude with a discussion of the importance of microbial arsenate reduction in the environment. The successful application and use of DARB should facilitate the effective bioremediation of arsenic contaminated sites.

멀티미디어 서비스를 위한 VP망의 다중화 이득에 관한 연구

장용철,오무송 조선대학교 동력자원연구소 1995 動力資源硏究所誌 Vol.17 No.2

The ATM(asynchronous transfer mode) has the suitable solution method and the characteristics of multiplexing in the multimedia services. This paper discuss network requirements using the concepts of the multimedia communication in platform label of the multimedia tele-service and module standard. In this paper, We presents to construct structure of ATM switching for management VP(virtual path) based on ATM in the B-ISDN and compute statical multiplexing gain in the ATM-VP network on the integrate network function. Therefore We indicated that our study is effective to multimedia system in the using VP-network as ATM techniques.

이화형비산염환원균의 특성

장용철,다까미자와 카즈히로,조훈,키쿠치 신타로 한국생물공학회 2012 KSBB Journal Vol.27 No.2

Although, microbial arsenic mobilization by dissimilatory arsenate-reducing bacteria (DARB) and the practical use to the removal technology of arsenic from contaminated soil are expected, most previous research mainly has been focused on the geochemical circulation of arsenic. Therefore, in this review we summarized the previously reported DARB to grasp the characteristic for bioremediation of arsenic. Evidence of microbial growth on arsenate is presented based on isolate analyses, after which a summary of the physiology of the following arsenaterespiring bacteria is provided: Chrysiogenes arsenatis strain BAL-1T, Sulfurospirillum barnesii, Desulfotomaculum strain Ben-RB, Desulfotomaculum auripigmentum strains OREX-4, GFAJ-1, Bacillus sp., Desulfitobacterium hafniense DCB-2T, strain SES-3, Citrobacter sp. (TSA-1 and NC-1),Sulfurospirillum arsenophilum sp. nov., Shewanella sp.,Chrysiogenes arsenatis BAL-lT, Deferribacter desulfuricans. Among the DARB, Citrobacter sp. NC-1 is superior to other dissimilatory arsenate-reducing bacteria with respect to arsenate reduction, particularly at high concentrations as high as 60 mM. A gram-negative anaerobic bacterium,Citrobacter sp. NC-1, which was isolated from arsenic contaminated soil, can grow on glucose as an electron donor and arsenate as an electron acceptor. Strain NC-1rapidly reduced arsenate at 5 mM to arsenite with concomitant cell growth, indicating that arsenate can act as the terminal electron acceptor for anaerobic respiration (dissimilatory arsenate reduction). To characterize the reductase systems in strain NC-1, arsenate and nitrate reduction activities were investigated with washed-cell suspensions and crude cell extracts from cells grown on arsenate or nitrate. These reductase activities were induced individually by the two electron acceptors. Tungstate,which is a typical inhibitory antagonist of molybdenum containing dissimilatory reductases, strongly inhibited the reduction of arsenate and nitrate in anaerobic growth cultures. These results suggest that strain NC-1 catalyzes the reduction of arsenate and nitrate by distinct terminal reductases containing a molybdenum cofactor. This may be advantageous during bioremediation processes where both contaminants are present. Moreover, a brief explanation of arsenic extraction from a model soil artificially contaminated with As (V) using a novel DARB (Citrobacter sp. NC-1)is given in this article. We conclude with a discussion of the importance of microbial arsenate reduction in the environment. The successful application and use of DARB should facilitate the effective bioremediation of arsenic contaminated sites. Although, microbial arsenic mobilization by dissimilatory arsenate-reducing bacteria (DARB) and the practical use to the removal technology of arsenic from contaminated soil are expected, most previous research mainly has been focused on the geochemical circulation of arsenic. Therefore, in this review we summarized the previously reported DARB to grasp the characteristic for bioremediation of arsenic. Evidence of microbial growth on arsenate is presented based on isolate analyses, after which a summary of the physiology of the following arsenaterespiring bacteria is provided: Chrysiogenes arsenatis strain BAL-1T, Sulfurospirillum barnesii, Desulfotomaculum strain Ben-RB, Desulfotomaculum auripigmentum strains OREX-4, GFAJ-1, Bacillus sp., Desulfitobacterium hafniense DCB-2T, strain SES-3, Citrobacter sp. (TSA-1 and NC-1),Sulfurospirillum arsenophilum sp. nov., Shewanella sp.,Chrysiogenes arsenatis BAL-lT, Deferribacter desulfuricans. Among the DARB, Citrobacter sp. NC-1 is superior to other dissimilatory arsenate-reducing bacteria with respect to arsenate reduction, particularly at high concentrations as high as 60 mM. A gram-negative anaerobic bacterium,Citrobacter sp. NC-1, which was isolated from arsenic contaminated soil, can grow on glucose as an electron donor and arsenate as an electron acceptor. Strain NC-1rapidly reduced arsenate at 5 mM to arsenite with concomitant cell growth, indicating that arsenate can act as the terminal electron acceptor for anaerobic respiration (dissimilatory arsenate reduction). To characterize the reductase systems in strain NC-1, arsenate and nitrate reduction activities were investigated with washed-cell suspensions and crude cell extracts from cells grown on arsenate or nitrate. These reductase activities were induced individually by the two electron acceptors. Tungstate,which is a typical inhibitory antagonist of molybdenum containing dissimilatory reductases, strongly inhibited the reduction of arsenate and nitrate in anaerobic growth cultures. These results suggest that strain NC-1 catalyzes the reduction of arsenate and nitrate by distinct terminal reductases containing a molybdenum cofactor. This may be advantageous during bioremediation processes where both contaminants are present. Moreover, a brief explanation of arsenic extraction from a model soil artificially contaminated with As (V) using a novel DARB (Citrobacter sp. NC-1)is given in this article. We conclude with a discussion of the importance of microbial arsenate reduction in the environment. The successful application and use of DARB should facilitate the effective bioremediation of arsenic contaminated sites.

창의설계입문의 PBL(Problem-Based Learning) 적용: 충남대학교 환경공학분야 사례

장용철,김건국,김민철 한국공학교육학회 2013 공학교육연구 Vol.16 No.2

An 'Introduction to Creative Engineering Design' course at College of Engineering at Chungnam National University is required for all freshmen. The objective of this course is to educate the freshmen with basic engineering design concepts and experiences in creative problem-solving approaches. It provides the students learning opportunities in solving engineering design problems through team efforts and creative approaches. Thus, this course emphasizes creative ideas and thinking, engineering design experiences to students over the course. This study presents the syllabus, the examples of PBL(problem based learning)-related activities as a team, and the results of the course evaluation and outcomes. Based on the results of this study, we can conclude that overall this course using PBL method had significant positive effects on the course outcomes and the creativity of the engineering freshmen in the department of environmental engineering at Chungnam National University. However, there are still efforts to be needed to improve the PBL-related activities in the course, including students' workload, financial supports, and team work. 본 연구에서는 충남대학교 환경공학과 1학년 학생을 대상으로 PBL 활용 창의설계입문의 교과목 운영 사례를 분석 제시하였다. 본 교과목은 공과대학 환경공학 전공을 선택하여 대학에입학한 1학년 학생들을 대상으로 PBL 교수법을 통해 창의적인사고와, 자기주도 학습, 문제해결능력을 배양하고자 하였다. 또한 학생들이 환경공학 분야의 창의적 공학설계 개념 및 방법을배우고 창의적인 아이디어를 도출하고 궁극적으로 공학 분야의전공 설계에 대한 관심과 흥미를 유발하고자 하였다. 본 논문에서는 환경공학 분야의 창의설계입문 교과목에 대한 PBL 교육을 개발하고 적용하여 학생들의 변화와 학습 성과를 심층 학생설문조사 및 강의평가를 통해 그 결과를 분석하였으며, 다음과같이 그 결과를 요약할 수 있다. 1. PBL 학습법을 적용한 창의설계입문 교과목은 학습 성과분석 결과, 학생 스스로 문제해결 과정에서 팀워크의 중요성과팀원으로서의 책임감을 깨닫는 계기가 되었다는 것이 가장 높게 나타났다. 또한 문제해결 과정에서 의사소통의 중요성과 효과적인 의사전달 능력을 배양하는 효과를 가져왔다. 아울러 학생들이 스스로 사고하는 능력과 창의성의 중요성, 팀 협동 능력이 향상되었다. 2. PBL 활용 창의설계입문의 교과목 수강을 통해 학생들이대체로 매우 만족하고 우수하다는 평가가 나타났으며, 특히 교수와 조교의 충분한 의사소통, 역할에 대해 만족하는 것으로 나타났다. 3. PBL-문제 제시를 통해 학생들로 하여금 흥미유발과 동기부여가 되었으며 공학설계 주제에 대해 창의적인 아이디어를 도출하고 논의하고 이를 실제 설계 제작하였다. 구두발표회와 시연회를 통해 의사전달 능력을 배양하였으며, 학생들이 설계에대한 흥미를 느끼며 직접 체험하는 효과를 거두었다. 4. 그러나 향후 PBL 활용창의설계입문 교과목 교육 시 PBL문제 제시의 수, 충분한 예산 확보 방안, 팀원 간 갈등 예방 등에 대한 체계적인 준비와 개선이 필요하다. 이상을 종합하여 요약한다면 충남대학교 공과대학 환경공학과 1학년 학생들을 대상으로 PBL 활용 창의설계입문 교과목은 학생들로 하여금 다양한 학습 성과를 거두었다. 향후 이러한PBL 활용 공학설계입문 교과목이 지속적으로 보완되어 개선된다면 학생들이 자기주도학습 능력을 배양하고 창의적인 아이디어를 창출하여 응용하고 관련 공학 설계 지식을 배우고 문제해결을 위한 창의성 배양에 기여를 할 수 있다.

화력발전소 석탄 바닥재의 재활용을 위한 물리화학적 특성분석 및 환경성 평가

장용철,이성우,임종명 한국폐기물자원순환학회 2009 한국폐기물자원순환학회지 Vol.26 No.8

The proper management of coal-fired bottom ash generated from coal power plants (often called "coal bottom ash") has been raised as an issue. The major management practice most commonly employed for the ash is disposal in landfills (ash pond) near ocean. The presence of large coarse and fine materials in the ash has prompted the desire to beneficially use it in an application such as fill materials. This objective, coupled with costs associated with ash pond disposal, provides incentive to explore beneficial use options. Prior to reuse application, the physical and chemical properties of the ash must be assessed with regard to the potential environmental impacts. A total of nine bottom ash samples were collected from an active ash pond and pretreated bottom ash piles in a coal-fired power plant. Each sample was tested for physical (e.g., particle size distribution, permeability) and chemical characteristics (e.g., pH, salinity, conductance, loss of ignition, unburned carbon content, oxides, total metal analyses). Three leaching tests such as Korea standard leaching test (KSLT), US toxicity characteristics leaching procedure (TCLP), and US synthetic precipitation leaching procedure (SPLP) were also performed to determine leachability of pollutants, especially metals. The concentrations of chemicals detected in the extracts were compared to appropriate standards, if possible, to assess potential leaching risks to the surrounding area. For the total metal analysis, most of the samples contained several ions such as Na, K, Ca, Mg, Al in relatively large quantities and trace chemical constituents such as B, Ba, Ni, Cr, Cu, and Zn. In the leaching experiments, three elements (Al, B, Ba) were commonly detected above their respective detection limits in a number of samples. The results of the leaching study indicate that the pollutants in the coal bottom ash were not of a major concern in terms of leaching risk to surface water and groundwater under reuse scenarios. However, care must be exercised in extending these results to field conditions because the results presented in this study are based on limited laboratory settings and a limited time frame.