• 한국대기환경학회지
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• 제2권2호
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• pp.9-18
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• 1986

For identification and apportionment of sources emitting particulate matters in environment, the multi-elemental characterization of size-density fractionated particulate matters was carried out. Eight types of samples were tested; soil, flyash released from burning of bunker-Coil, diesel oil, coal, and soft coal, urban road-way dust, urban dust fall, and airborne particulate matter. The fractions of particulate matters obtained by heavy liquid separation methos with a series of dichloromethane-bromoform were then analyzed using atomic absorption spectrophotometry for Ni, Cr, Cu, An, Fe, Al, and Mg. Each sample showed a different concentration profile as a function of density, and a number of useful conclusions concerning characterization of elemental distribution were obtained. From the density distributions of elements in soil, the maximum value was found for all elements in the density range of 2.2 $\sim 2.9g.cm^{-3}$, including the density of $SiO_2$. However, the distribution of metallic compounds with the density lower than $2.2g.cm^{-3}$ was prevalent in urban roadway dust, urban dust fall, and airborne particulate matter. And the density distribution curves of these urban dusts also have the higher distribution at the density of 2.2 - 2.9g.cm^{-3}$, including the density of wind-blown silica. This tendency generally was prevalent in the natural source elements, such as Al, Fe, Mn, and Mg. The maximum values were found in the density ranges of 1.3 $\sim 2.2g.cm^{-3}$ from the density distribution of elements in oil fired flyash. These distributions of anthropogenic source elements, such as Zn, Ni, Cu, and Cr were higher predominately than those of natural source elements. And the higher distribution was found in the density range of $2.2 \sim 2.9g.cm^{-3}$ from the density distribution of elements in coal and soft-coal fired flyash. These distributions showed similar patterns to soil. But anthropogenic source elements somewhat predominated at the density ranges of $1.3 \sim 2.2g.cm{-3} and 2.9g.cm^{-3}$ to soil. Therefore the higher distribution of anthropogenic source elements in the density ranges of $1.3 \sim 2.2g.cm^{-3} and 2.9g.cm^{-3}$ was considered as anthropogenic origin.

• 한국환경과학회지
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• 제11권9호
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• pp.971-977
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• 2002

The isolated strain, Rhodococcus sp. EL-GT was able to degrade high phenol concentrations up to 10 mM within 24 hours in the medium consisting of 5.3 mM $KH_2PO_4$. 95 mM $Na_2HPO_4$, 18mM $NH_4NO_3$, 1 mM $MgSO_4{\cdot}7H_2O$,\;50{\mu}M CaCl_2$,\;0.5 {\mu}M FeCl_3$, initial pH 8.0, temperature $30^{\circ}C$ in rotary shaker at 200 rpm. This strain was good cell growth and phenol degradation in the alkaline pH range range, and the highest in the pH range of 7 to 9. The microorganism was able to grow at the various chlorinated phenols, benzene, toluene, and bunker-C oil. As Rhodococcus sp. EL-GT was good capable of attachment on the acryl media, it would be used as microorganism to consist of biofilm in wastewater treatment.

• 한국항해항만학회지
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• 제28권5호
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• pp.463-468
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• 2004

수리조선소에서 발생하는 TBT 함유 선박세척폐수의 용매추출 처리기술을 개발하기 위한 기초연구로서 인공 선박세척폐수를 이용하여 선박용 및 자동차용 디젤, 벙커 B유, 신너, 톨루엔, 에테르 등의 여러 가지 용매들의 TBT 추출효율을 비교하였으며, 추출효율에 대한 추출용매의 양 및 교반시간, 강도, pH 등의 추출조건의 영향을 평가하였다. 선박용 경유는 신나, 병커B 등에 비해 상대적으로 우수한 TBT 추출효율을 보였으며, 적정 추출용매 주입량은 폐수 IL 당 용매 10mL로 평가되었다 TBT 추출을 위한 교반강도가 50rpm에서 250rpm으로 증가함에 따라 잔류 TBT 농도는 약 120ppb에서 2.8ppb로 크게 감소하였다 잔류 TBT는 추출 1시간이후 크게 감소하였으며, 5시간 이후부터는 다시 증가하였다. 추출효율에 대한 Ph의 영향은 크지 않았으나, pH 6∼7의 약산성영역에서 양호한 추출효율을 보였다.

• 한국대기환경학회지
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• 제20권3호
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• pp.317-330
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• 2004

The Purpose of this study was to develop the P $M_{2.5}$ source Profiles, which are mass abundances (fraction of total mass) of a chemical species in P $M_{2.5}$ source emissions. The source categories studied were soil, road dust, gasoline and diesel vehicles, industrial source, municipal incinerator, coal-fired power plant, biomass burning, and marine. The chemicals analyzed were ions. elements. and carbons. From this study, soil source had the crustal components such as Si, hi, and Fe. In the case of road dust. Si, OC, Ca, Fe had large abundances. The abundant species were S $O_4$$^{2-}$, C $l^{[-10]}$ , N $H_4$$^{+}$, and EC in the gasoline vehicle and EC, OC, C $l^{[-10]}$ , and S $O_4$$^{2-}$ in the diesel vehicle. The main components were S $O_4$$^{2-}$, S N $H_4$$^{+}$, and EC in the industrial source using bunker C oil as fuel, C $l^{[-10]}$ , N $H_4$$^{+}$, Fe, and OC in the municipal incinerator source, and Si, Al, S $O_4$$^{2-}$, and OC in the coal -fired power plant source. In the case of biomass burning, OC, EC, and C $l^{[-10]}$ were mainly emitted. The main components in marine were C $l^{[-10]}$ , N $a^{+}$, and S $O_4$$^{2-}$.EX> 2-/.

• Journal of Preventive Medicine and Public Health
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• 제42권2호
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• pp.73-81
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• 2009

Objectives : This study presents a scientific basis for the establishment of an environmental health contingency plan for dealing with accidental coastal oil spills and suggests some strategies for use in an environmental health emergency. Methods : We reviewed the existing literature, and analyzed the various fundamental factors involved in response strategies for oil spill. Our analysis included data derived from Hebei Spirit oil spill and used air dispersion modeling. Results : Spill amounts of more than 1,000 kl can affect the health of residents along the coast, especially those who belong to vulnerable groups. Almost 30% of South Korean population lives in the vicinity of the coast. The area that is at the highest risk for a spill and that has the greatest number of people at risk is the stretch of coastline from Busan to Tongyeong. The most prevalent types of oil spilt in Korean waters have been crude oil and bunker-C oil, both of which have relatively high specific gravity and contain volatile organic compounds, polycyclic aromatic hydrocarbons, and metals. In the case of a spill of more than 1,000 kl, it may be necessary to evacuate vulnerable and sensitive groups. Conclusions : The government should establish environmental health planning that considers the spill amount, the types of oil, and the distance between the spot of the accident and the coast, and should assemble a response team that includes environmental health specialists to prepare for the future oil spill.

• 한국유기농업학회지
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• 제20권3호
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• pp.267-282
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• 2012

In this study, RPS system, one of the renewable energy support systems, is utilized for economic analysis of solar generation equipment and the fuel cost savings plan for controlled horticulture farms with high fuel-cost dependency and facility applicability were evaluated. On the exterior of the upper layer of glass greenhouse (9917$m^2$) of controlled horticulture farms using bunker C oil, half of the area (4958$m^2$) was utilized for theoretical installation and operation of 450kW-level solar power generator, and as the result, first, the effect of investment cost only of solar generation system was found to be quite excellent, but it was analyzed that there were limits to saving the fuel costs of the controlled horticulture farms. Second, when geothermal system was first introduced in the farm and solar system was additionally introduced, it was analyzed that the effect of introducing solar system was excellent. In order to apply such effects to the sites of farming, partial supplementation of RPS system which is being uniformly applied regardless of the purpose of renewable energy is necessary. When the subject of use directly install facilities where it is directly connected to national added-value such as food security created by the farming industry, it is necessary to introduce appropriate system that corresponds to such. Moreover, it was studied that the quick development of demonstrative complex that can practically evaluate the applicability of renewable energy in farming industry and interest and preparation of related institutions in financial support structure for its site application would lead to success.

• Journal of Welding and Joining
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• 제35권3호
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• pp.82-87
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• 2017

Recent trends in shipbuilding and offshore industries are a huge increase in the ship size and the exploration and production of oil and natural gas in the arctic offshore region. High performance steel plates are required by these industrial trends. Also in IMO(International Maritime Organization) has begun to regulate of fuel of ship to environmental protection, therefore it is little bit difficult to use bunker-C oil to working ship. As the problem of environmental change such as global warming is emerged, the operation of the ship is considered to be involved in the environmental change problem, and the regulation of environmental pollution is gradually strengthened. As these environmental regulations are strengthened demand for LNG fuel ships is rapidly increasing. Currently, cryogenic steels used in LNG tanks include aluminum alloy, SUS 304, and 9%-Ni steel. Those steels are has high cost to construction of large LNG carrier. The new materials were suggested several steel mills to decrease construction cost and easy construction. The new cryogenic steel should be evaluate safety to applied real structure include LNG ship. Therefore, in this study, fracture toughness of weld joints were investigated with cryogenic steel for application of LNG tank.

• 한국환경과학회지
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• 제16권7호
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• pp.799-804
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• 2007

Oil spill caused severe effects on the marine fauna and flora due to direct contact of organisms with the oil and even in regions not directly affected by the spill. This study was conducted to understand the effects of the oil spill accidents and the use of dispersant on the red tide of Cochlodinium polykrikoides. Crude oil produced in Kuwait, bunker-C, kerosene and diesel oil, and a chemical dispersant produced in Korea, were added with a series of 10 ppb to 100 ppm in the f/2-Si medium at $20^{\circ}C$ under a photon flux from cool white fluorescent tubes of $100\;mol\;m^{-2}\;s^{-1}$ in a 14: 10 h L:D cycle for the culture of C. polykrikoides. In low concentrations of ${\leq}$ 1 ppm of examined oils no impact on the growth of C. polykrikoides was recorded, while in high concentration of ${\geq}$ 10 ppm, cell density was significantly decreased with the range of 10 to 80% in comparison with the control. The growth of C. polykrikoides after the addition of the dispersant and the mixtures combined with oils and a dispersant of ${\geq}$ 10 ppm appeared to decrease, whereas the growth of C. polykrikoides exposed to ${\leq}$ 100 ppb showed little serious impact. However, almost all the C. polykrikoides cells were died regardless of a dispersant and combined mixtures within a few days after the addition of high concentrations.

• Elastomers and Composites
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• 제39권1호
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• pp.61-70
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• 2004

본 연구는 폐식용유를 이용하여 아스팔트계 봉함재(sealant)를 제조하는 것이다. 아스팔트계 봉함재는 포장도로의 균열 봉함재 및 교량 조인트용 봉함재로 사용되는 재료이다. 아스팔트(AP-5), 열가소성 고무(SBS triblock copolymer), 점착제(tackifier) 및 안정제를 기본 성분으로 하여 연화제로 방향족계 또는 파라핀계 공정유, DOP(dioctyl phthalate), 벙커 C유 또는 폐식용유와 혼합하여 침입도, 연화점, 신도 및 인장 접착 신율(상온 및 저온)을 측정하였다. 연화제의 종류 및 함량에 따라 봉함재의 물성이 크게 변화하였다. 폐식용유 또는 DOP를 사용한 경우가 저온 인장 접착 특성이 가장 우수하였다. 폐식용유 함량이 증가함에 따라 아스팔트 봉함재의 침입도는 및 인장 접착 신율은 증가하였고 증량제로 탈크를 첨가할 경우 함량에 비례하여 침입도 및 저온 인장 신율은 감소하였다. 배합비를 최적화하여 침입도가 낮으면서도 저온 인장 접착성이 우수한 아스팔트 봉함재를 제조할 수 있었다.

• 플랜트 저널
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• 제12권3호
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• pp.39-45
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• 2016

기존 벙커C유에 바이오중유 혼합비율을 50%, 80% 및 100%로 변화시키면서, 발전기 출력 320 MW, 380 MW 일 때 각각의 시간당 연료소비량을 측정하였다. 벙커C유 전소일 때의 시간당 연료소비량과 비교한 결과 발전기 출력 320 MW에서 바이오중유 혼합비율이 50%부터 100%까지 높아짐에 따라 시간당 연료소비량이 11.0%에서 20.4%까지 증가함을 알 수 있었다. 또한 발전기 출력 380 MW에서는 바이오중유 혼합비율이 50%부터 100%까지 높아짐에 따라 시간당 연료소비량이 12.0%에서 21.1%까지 증가함을 알 수 있었다. 더 나아가 측정된 시간당 연료소비량과 발전기 출력, 연료의 고위발열량을 이용하여 발전효율을 산출하였고, 발전기 출력 320 MW, 380 MW에서 모두 바이오중유 혼합비율이 50%부터 100%까지 높아지면서 발전효율은 감소함을 확인하였다.