• Carbon letters
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• 제12권3호
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• pp.152-161
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• 2011

Activated carbon was prepared from pre-carbonized petroleum coke. Textural properties were determined from studies of the adsorption of nitrogen at 77 K and the surface chemistry was obtained using the Fourier-transform infrared spectrometer technique and the Boehm titration process. The adsorption of three aromatic compounds, namely phenol (P), p-nitrophenol (PNP) and benzoic acid (BA) onto APC in aqueous solution was studied in a batch system with respect to contact time, pH, initial concentration of solutes and temperature. Active carbon APC obtained was found to possess a high surface area and a predominantly microporous structure; it also had an acidic surface character. The experimental data fitted the pseudo-second-order kinetic model well; also, the intraparticle diffusion was the only controlling process in determining the adsorption of the three pollutants investigated. The adsorption data fit well with the Langmuir and Freundlich models. The uptake of the three pollutants was found to be strongly dependent on the pH value and the temperature of the solution. Most of the experiments were conducted at pH 7; the $pH_{(PZC)}$ of the active carbon under study was 5.0; the surface of the active carbon was negatively charged. The thermodynamic parameters evaluated for APC revealed that the adsorption of P was spontaneous and exothermic in nature, while PNP and BA showed no-spontaneity of the adsorption process and that process was endothermic in nature.

• 한국대기환경학회지
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• 제19권5호
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• pp.469-490
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• 2003

Atmospheric concentrations of persistent organic pollutants (POPs) were measured at Gosan, Jeju in November 2001 and spring 2002, each time for two weeks. Primary target pollutants were organochlorine pesticides, coplanar polychlorinated biphenyls (co- PCBs), and dioxin/furans listed in the Stockholm Convention adopted in May 2001. Polycyclic aromatic hydrocarbons (PAHs) were also measured in order to understand the overall characteristics of the POPs distribution as well as PM$_{2.5}$, a potent carrier of POPs. In the latter part of the measurement period of November 2001, almost every pollutant of combustion origin including dioxin/furans went high probably due to influence of emissions in the nearby area. The characteristics of atmospheric environment at Gosan in this period were rather close to urban areas far from those of a background area. A severe dust storm swept for three days at the end of the measurement period of spring 2002. However, changes in pollutant concentrations were relatively small except PM$_{10}$. Nevertheless, increases in particulate PAHs and OCDD (octachlorinated dibenzo-p-dioxins), mostly present in fine particles, were observed. Trends in organochlorine pesticide variations were mixed although possible volatilization of DDT residues from soil was inferred from the measurements of spring 2002.2.2.

• 한국대기환경학회지
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• 제24권2호
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• pp.229-237
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• 2008

Hazardous air pollutants emitted from the oil refinery plant were surveyed from 1993 US and 2005 Korean TRI data. Toluene, xylene, methanol, MTBE and n-hexane, relatively large in amount of fugitive emission, are considered as candidates of newly designated HAPs in Korea. The sealed oil pump, one of equipments among fugitive sources in the crude oil distillation tower was examined for the estimation of amounts of annual HAPs emissions according to several calculation methods using registered emission factors. Emission rates showed to be decreased with following calculation factors; average emission factor>pegged emission factor>concentration emission factor>correlation equation. Annual emission amounts of benzene, toluene, xylene. ethyl benzene and nhexane from the distillation tower were estimated and amounts of these HAPs calculated with TVOC concentrations obtained from LDAR program and correlation equations showed only 6% of those from using concentration factors.

• 한국대기환경학회지
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• 제29권1호
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• pp.1-9
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• 2013

Hazardous Air Pollutants (HAPs) are difficult to measure, analyze and assess for risk because of low ambient concentrations and varieties. Types of HAPs are Volatile organic compounds (VOCs), Polycyclic aromatic hydrocarbon (PAHs) and Aldehydes. HAP emissions from vehicles are a contributor to serious adverse health effects in urban areas. In this study, hazardous air pollutant emissions from road transport vehicles by Non-methane volatile organic compounds (NMVOC) weight fraction and PAHs emission factors are estimated in 2008. The top-five-most hazardous air pollutant emissions were estimated to toluene 864.3 ton/yr, acrolein 690.6 ton/yr, acetaldehyde 554.5 ton/yr, formaldehyde 498.7 ton/yr, propionaldehyde 421.6 ton/yr in 2008. The results for a cancer and non-cancer risk assessment of HAPs emissions show that the major cancer driver is formaldehyde and the non-cancer driver is acrolein.

• 청정기술
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• 제11권1호
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• pp.29-39
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• 2005

잔류성 유기오염 물질 (POPs) 중의 하나인polychlorinated biphenyls (PCBs)는 강한 독성 및 난분해성으로 암, 내분기계장애(환경호르몬) 등을 유발할 수 있는데, 대부분의 PCBs는 변압기, 콘덴서 같은 전기 설비의 절연유를 오염시키고 있다. 국내외의 PCBs 관련 오염 현황및 관련 대책을 살펴보고, PCBs를 무해화 분해 처리하기 위한 기술로서 소각, 화학적 탈염소, 광화학, 생물학적 처리를 중심으로 국내외 기술 현황 비교 평가 및 특허 출원 동향을 분석하였다. 이를 바탕으로 향후 국내 PCBs 기술 개발및 대응 방향과 전망을 기술하였다.

• 한국물환경학회지
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• 제31권3호
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• pp.313-318
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• 2015

To study the influence of changes in river discharge on water quality of the main stem of the Geum River, we investigated variation of inflow load from tributaries with river discharge. We also studied the mixing behavior of pollutants during mixing of waters of the main stem and Gap Stream. For this study, we collected water quality data such as suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) representing pre-monsoon, monsoon, and post-monsoon events of 2013 from a website of Water Information System. Based on inflow load, the Gap and Miho streams may be ones of tributaries which may largely influence water quality of main stem in upper river region. The Suksung and Nonsan Streams seemed to further affect water quality downstream. Results of modified EMMA indicated SS and TP may have another source(besides Gap Stream) at pre-monsoon, monsoon, and post-monsoon period. In contrast, TN and organic matter (BOD, COD, TOC) were conservative at pre-monsoon and post-monsoon. However, when river discharge increased, these pollutants may also came from unspecified non-point sources. Therefore, we need to attempt to find non-point sources for the pollutants in the main channel of upper Geum River region.

• 한국항해항만학회지
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• 제39권4호
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• pp.345-351
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• 2015

실험실 규모의 관 실험을 통하여 연안오염퇴적물의 생물정화 효능에 대한 생물활성촉진제 주입 깊이의 영향을 평가하였다. 생물활성촉진제를 실험관에 충진 된 오염퇴적물의 표면과 표면으로부터 3cm, 6cm, 10cm 위치에 주입한 후 1개월 및 3개월 후 퇴적물의 유기물 및 중금속의 특성 변화를 조사하였다. 시험 오염퇴적물의 화학적 산소요구량, 총고형물 및 휘발성고형물 함량은 생물활성촉진제를 주입하지 않은 대조구에 비해 1개월 후 및 3개월 후에서 크게 감소하였으며, 생물활성촉진제 주입 깊이 3cm에서 최대값을 보였다. 그러나, 오염퇴적물에 주입한 생물활성촉진제의 깊이를 6cm 및 10cm로 증가하였을 때 유기오염물질 감량정도는 점차 감소하였다. 중금속 존재형태변화는 생물활성촉진제 주입 깊이 3cm에서 안정한 형태인 유기물 결합분율과 광물내 잔류분율이 현저하게 증가하였다. 오염퇴적물의 현장생물정화를 위한 최적의 생물활성촉진제 주입 깊이는 퇴적물의 상부 표면으로부터 3cm로 평가되었다.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1999년도 춘계 학술논문발표회 논문집
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• pp.271-276
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• 1999

미국을 비롯한 선진국들은 이미 휘발성 유기화합물(volatile organic compounds) 과 독성 중금속(toxic metals)을 비롯한 유해 대기오염물(hazardous air pollutants)에 대해 ATEOS (Airborne Toxic Element and Organic Species), TEAM(Total Exposure Assessment Measurement) 연구등의 대규모 연구를 통하여 인체에 미치는 영향이 가장 큰 물질군이 휘발성 유기화합물임을 밝혀낸 바 있다. (중략)

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2003년도 추계학술대회 논문집
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• pp.291-292
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• 2003

잔류성 유기오염물질(POPs; Persistent Organic Pollutants)은 환경 내에서 분해가 느려 잔류성이 높고, 생체 지질에 축적되는 독성이 강한 특성이 있다. 따라서 스톡홀름 협약(2001년 5월 23일)에서 12종의 POPs 물질에 대해 국제적 사용금지 및 관리가 결정되었다. POPs는 대부분 반휘발성(semi-volatile) 이어서 대기 중 장거리 이동되어 배출지와 다른 곳에 침적되는 것이 보고되어있다. 이러한 물질들의 대기 중 잔류량과 기체상과 입자상의 분포 특성을 살펴서 환경 내 이동성을 파악하는 것은 인체위해성 수준을 알아내는데 중요한 자료이다. (중략)

• 한국막학회:학술대회논문집
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• 한국막학회 1994년도 춘계 총회 및 학술발표회
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• pp.29-32
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• 1994

The increasing environmental risks exert strong demands for the knowledge of environmentally significant compounds and the reduction of such compounds on the earth. The risk reduction can, in principle, be most effectively achieved by minimizing the formation of environmental pollutants, by-products in many cases, during processes in factories, power plants and other sources. This can be done by on-line, real time monitoring the formation of pollutants at the moment when they are formed, and thereby through the feed-back control of the process.