• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.191-193
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• 2000

오존 등 기체상 오염물질의 식물 표면에 대한 건성침적은 식물의 생물학적 활동에 피해를 줄 수 있으며(Runeckles and Chevone, 1992; Chappelka and Chevone, 1992), 건성침적 현상은 노출된 식물지표 환경의 화학적 특성을 변화시키는 작용으로 관심의 대상이 되고있다(Businger, 1986; Galbally et al., 1986; Chang et al., 1987; Wesely, 1989; Hicks et al., 1989). 이러한 기체상 오염물질의 침적현상은 대기질 관리에 있어서 오염물질의 적절한 감소계획을 산정ㆍ평가하기 위하여 지상 오염물질의 농도를 정확하게 추정하는 과정에서 필수적으로 고려되어야 하는 부분이다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.111-112
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• 2001

대기로부터 침적된 물질로 인해 토양오염과 수질오염 현상이 심화될 뿐만 아니라 환경 생태계도 영향을 받는다는 것이 밝혀지면서 대기 침적 현상에 대한 관심이 커지고 있다. 침적은 대기 중의 여러 미량 물질들이 환경계에 미치는 영향과 그들의 이동을 조절하는 중요한 기작 중 하나이다. 중금속은 가장 오래전부터 알려진 독성물질로서, 약 30가지 금속이 사람에게 독성을 발현하는 것으로 알려져 있고, 그 중 일부 중금속은 발암성을 가지고 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.131-132
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• 2002

우리나라는 식수의 90% 이상을 지표수로부터 얻고 있다. 그만큼 식수를 위한 취수가 외부의 위험에 노출되어 있음을 의미한다. 원칙적으로 어떠한 대기오염물질의 침적도 수질에 영향을 미칠 수 있다 황과 질소분은 대표적인 산성물질로 수질을 산성화시킬 수 있다 그러나 우리나라 주요 하천과 호소는 적지 않은 양의 산성물질 침적에도 불구하고 pH는 상수원수 등급기준인 6.5-8.5사이로 양호하다 (환경부, 2001). 하천, 호소의 완충 능력이 침적에 비하여 충분함을 의미하나 구체적 메커니즘은 분명치 않다. (중략)

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.775-784
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• 2000

Nitrate dry deposition fluxes were directly measured using knife-leading-edge surrogate surface (KSS) covered with greased strips and a water surface sampler (WSS). The average gaseous flux ($8.3mg/m^2/day$) was much higher than the average particulate one ($3.0mg/m^2/day$). The best fit gas phase mass transfer coefficient (MTC) of $HNO_3$ was obtained by linear regression analysis between measured gaseous flux containing nitrogen compounds and measured ambient $HNO_3$ concentration. The result showed that the MTCs of $HNO_3$ were approximately two times higher than those of $SO_2$. Especially, during the ozone action day, measured gaseous fluxes containing nitrogen compounds were much higher than those ones calculated as the product of measured ambient $HNO_3$ concentration and gas phase MTC of $HNO_3$, which is calculated from MTC of $SO_2$ using Graham's diffusion law. This result indicated that other nitrogen compounds except $HNO_3$ contributed to gaseous flux containing nitrogen compounds into the water surface sampler. The theoretical calculations suggest the contributions of nitrous acid ($HNO_2$) and PAN to the gaseous dry deposition flux of nitrogen containing compounds to the WSS.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.4
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• pp.330-336
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• 2012

We surveyed and evaluated quantities and distribution characteristics of debris on the sea floor around active fishing grounds around the islands in the southwest coast of Korea in 2007 where the average depth is below 40m. Proper recovery gears mainly to haul the derelict fishing gears are selected considering the sea bed types of the areas. The collected debris amounts were used to estimate the total amount of the surveyed area. The number of hauls per trial times the amount of the debris was extended to whole sampling area and the weighting factor from the opinion was applied to reach the total amount of marine debris on the floor. The amount of the deposited marine debris around Wangdeung-do area is estimated as about 686 $kg/km^2$, and the cost of the collection and treatment for the deposited marine debris is estimated about 3.9 billion KRW after consideration of the proper size of the working ships, labor, transport and treatment cost.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.508-509
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• 2003

대기 중 입자상 물질의 건식 침적 속도는 그 과정의 복잡성으로 인해 모형을 이용한 연구 시 종종 일정한 값으로 간주되어 왔다. 그러나 입자상 물질의 전체 침적 속(flux)에서 건식 침적 속(flux)이 차지하는 부분은 무시할 수 없는 양이며, 따라서 입자상 물질의 기후 및 환경에 대한 영향을 평가하기 위해서는 이 과정의 정량적인 추정이 필요하다. 본 연구는 프랑스 기상청(Meteo-France)의 대기화학수송모형(CTM)인 MOCAGE에 에어로졸 모듈을 개발하는 일환으로 지표 특성 및 지표 가까이의 미기상학적 조건 등을 고려하여 입자 크기 별 입자상 물질의 건식 침적 속도를 모수화 하였다.(중략)

• Journal of the Korean Chemical Society
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• v.40 no.1
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• pp.50-58
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• 1996

In the presence of metal ions(Co(Ⅱ), Ni(Ⅱ), Sr(Ⅱ), Cu(Ⅱ), Fe(Ⅲ), U(Ⅵ)), the sedimentation of humic acid was increased at constant pH with increasing metal concentration and the strength was increased in the following order: Sr < Ni < Co < Cu < Fe < U. At constant metal concentration, Cu(Ⅱ), Ni(Ⅱ), and Co(Ⅱ) ions caused an increase in sedimentation of humic acid as the solution pH increased, whereas Fe(Ⅲ) and U(Ⅵ) ions caused a decrease. Sr(Ⅱ) ions did not affect the sedimentation even with the variation of pH. The analysis of FT-IR spectra for the sediments prepared from the reaction between humic acid and metal ions showed that metal ions were bound to humic acid to form complexes, suggesting that the metal complexation plays an important role in the sedimentation of humic acid.

• Korean Journal of Materials Research
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• v.8 no.9
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• pp.865-870
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• 1998

The surfaces of titanium specimens were modified by immersion in calcium phosphate buffered solutions (pH 5.8, 7.0, 8.0) for 10 days and simulated body fluid(SBF) for 30 days by turns. The modified surfaces were characterized using scanning electron microscopy(SEM), X-ray diffractometery(XRD) and Fourier transform infrared spectrophotometer(FT-IR), and compared with specimen immersed in only SBF. The results indicated that the immersion in calcium phosphate buffered solutions accelerated the formation of the surface films. The formed layer showed granular shaped microstructure, and recognized as calcium phosphate such as a hydroxyapatite(HA) or a $\beta$-tri-calcium phosphate($\beta$-TCP). The thickness of the layer increased of the buffered solutions in order of pH 8.0, 7.0 and 5.8 and the density increased in order of pH 7.0, 8.0 and 5.8.

• Membrane Journal
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• v.5 no.2
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• pp.74-80
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• 1995

Asymmetric poly(vinyl alcohol) (PVA) membranes were prepared by varying the precipitation conditions of the phase inversion technique, and the influences of precipitation conditions on the water uptake of the membrane were investigate. The degree of water uptake of the membrane increased and reached a certain maximum value, as the precipitation time increased. However, it decreded after that. As the precipition temperauure became lower, the degree of water uptake increased more or less. The addition of a nonionic surfactant to the precipitaon solution was effective reducing the precipitation time by lowering the surface tension of the precipitation solution, but ig didn't change the maximum value of its own degree of water uptake. In addition, the relationship between the degree of water uptake and the separation characteristics and mechanical properies of the membrane were investigated. The selectivity factor of the membrane for pervaperation separation decreased, but the permeate flux increased, respectively, with increasing the degree of water uptake. The tensile strength and elongation of the membrane, respectively, increased to a maximum value with increasing the degree of water uptake, and then decreased abtuptly.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1995.10a
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• pp.151-153
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• 1995