• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.147-148
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• 2002

대기중의 유해 에어로솔의 장거리 이동에 대한 과학적인 자료를 마련하기 위해 2002년 3월 29일부터 4월 11일까지 제주도 서쪽 끝에 위치한 고산사이트에서 PM$_{2.5}$와 PM$_{10}$ 에어로솔의 샘플링을 수행하였다. 이로부터 제주도 고산지역 대기 중 PM$_{2.5}$/PM$_{10}$의 물리적, 화학적 특성을 파악하고, 유기물 측정 결과를 통한 오염물질의 배출원 추정 및 장거리 이동가능성을 검토하고자 하였다. (중략)(중략)(중략)

• JOURNAL OF ELECTRICAL WORLD
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• s.254
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• pp.53-61
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• 1998

오존은, 그 강력한 산화력에 의하여 살균, 탈취, 탈색과 유기물 제거 등의 효과를 복합적으로 얻을 수 있고 또한 신속하게 산소로 분해되어 잔류하지 않기 때문에 환경개선에 사용하기에 이상적인 물질이다. 미쓰비시전기에서는 이러한 오존의 이점에 착안하여 1970년부터 오존발생기와 오존처리설비의 개발, 제품화를 추진하여 왔다. 오존에 의한 고도처리가 널리 일반에게 인정되어 그 수요가 높아지고 있는 오늘날에 있어서도 보다 많은 오존설비의 보급을 위하여 오존기술의 개발에 힘쓰고있다. 본고에서는 상하수도 오존고도처리의 기술동향의 일부로 시도되고 있는 다음의 세 가지 내용을 소개한다. (1)오존처리시스템의 자에너지, 고효율화 기술 방전갭의 단축화, 관분내압력의 고압화로 고농도$\cdot$고효율의 오존발생을 실현하여 자전력화를 가능케 한 신형오조나이저를 개발 제품화하였다. (2)오존 반응조 내에서의 산기장치특성의 파악 모델화가 곤란한 신기장치에 대하여 실설비규모의 실험설비를 사용하여 그 산기특성을 분명히 하였다. (3)과산화수소첨가 오존처리법에 의한 하수처리수의 재생이용 과산화수소첨가 오존처리법에 의하여 장기간에 걸쳐 하수처리수를 전유기탄소(TOC)3mg/$\ell$이하로까지의 처리를 달성하여 하수처리수를 수도수레벨로까지 고도로 정화할 수 있음을 실증하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.60-60
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• 2010

최근 사람의 피부나 내부 장기처럼 수축과 팽창이 일어나는 부위 등에 이식 가능한 소자 개발에 대한 연구가 많이 보고되었다. 현재 이런 stretchable electronics에 대한 연구는 channel material로서 실리콘이나 유기물, 그리고, 광학 리소그래피가 가능한 micro-electronics 에 국한되어 있다. 우리는 CVD 로 성장된 수십 나노미터의 직경을 갖는 $SnO_2$ 나노선을 슬라이딩 전이하여 실리콘 웨이퍼 상에서 소자화하고 이를 스트레칭이 가능한 PDMS 기판에 전이하여 stretchable nanowire device를 구현하였다. 해당 소자는 윗면과 아랫면 모두 폴리머로 덮여 있고 측정을 위한 전극이 따로 구성되어 있어 소자 특성의 열화가 최소화되게 제작되었으며, 수축과 팽창 시 받는 스트레인 또한 최소화하는 mechanical neutral structure를 갖게 제작되었다. 또한, 소자와 소자 혹은 소자와 전극간의 연결을 S자 형태로 구성하여 기판으로 사용된 PDMS를 수십 % 스트레칭하여도 소자의 전기적 특성이 유지되는 것을 확인하였다. 이처럼 스트레칭이 가능한 나노선 소자는 구김이나 잡아 늘여지게 되는 다양한 표면위에 간단하게는 논리회로뿐만 아니라 나노선의 장점을 이용한 다양한 센서 및 기능 소자로서 응용이 가능할 것으로 예상된다.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.93-102
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• 2007

The runoff characteristics of organic matter in turbid water were investigated in eleven tributary streams of the Han River system, Korea. The flow-weighted event mean concentrations of organic matter ranged from 1.5 to 3.2 mg $L^{-1}$ of DOM and 2.2 of 29.1 mg $L^{-1}$ of POM, respectively. The SUVA value which reflects the proportion of humic substance in organic matters was higher during the rainfall season, meaning that the runoff of refractory form increase in this period. Stable carbon isotope ratios of both POM and DOM were different among streams, which reflect the sources of organic matter. DOM isotope ratios were less depleted of $^{13}C$ than that of POM by approximately 1 to $2%_{\circ}$ ${\delta}^{13}C$ of the several turbid streams (the Mandae Stream, the Jawoon Stream, and the Daegi stream) were heavier than those of clear streams. ${\delta}^{13}C$ values in the turbid upstream tributaries were similar to those of downstream reaches (such as the Soyang River, the Sum River, and the Seo River). From the ${\delta}^{13}C$ analysis of POM it could be calculated that $C_4$ pathway contributed approximately 15.9 to 23.6% of organic matter in several turbid upstream sites, and over 20% in the three sites of large downstream reaches. On the contrary it contributed only 9.1 to 12.8% in clear streams of forest watersheds. In the Soyang River, $C_4$ pathway organic matter contributed 8.8% of the DOM pool.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.83-93
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• 2015

This study investigated genetic, mineralogical and spectral characteristics of oil shale and coal samples in Dundgobi area, Mongolia. Based the Rock/Eval and Total organic carbon (TOC) analysis, kerogen type, hydrogen quantity, thermal maturity and depositional environment were confirmed. Moreover, the mineral composition of oil shale and coal samples were analyzed by XRD and spectroscopy. The result of Rock Eval/TOC analysis revealed that the samples of Eedemt deposit are immature to mature source rocks with sufficient hydrocarbon potential, and the kerogen types were classified as Type I, Type II and Type III kerogen. On the other hand, the samples from Shine Us Khudag deposit were mature with good to very good hydrocarbon potential rocks where kengen types are defined as Type I, Type II/III and Type III kerogen. According to the carbon and sulfur contents, the depositional environment of the both sites were defined as a freshwater depositional environment. The XRD analysis revealed that the mineral composition of oil shale and coal samples were quartz, calcite, dolomite, illite, kaolinite, montmorillonite, anorthoclase, albite, microcline, orthoclase and analcime. The absorption features of oil shale samples were at 1412 nm and 1907 nm by clay minerals and water, 2206 nm by clay minerals of kaolinite and montmorillonite and 2306 nm by dolomite. It is considered that spectral characteristics on organic matter content test must be tested for oil shale exploration using remote sensing techniques.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.95-108
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• 2015

Nano-sized iron colloids are formed as acid mine drainage is exposed to surface environments and is introduced into surrounding water bodies. These iron nanomaterials invoke aesthetic contamination as well as adverse effects on aqueous ecosystems. In order to control them, the characteristics of their behaviour should be understood first, but the cumulative research outputs up to now are much less than the expected. Using zero-valent iron (ZVI) and magnetite, this study aims to investigate the behaviour of iron nanomaterials according to the change in the composition and pH of background electrolyte and the concentration of natural organic matter (NOM). The size and surface zeta potential of iron nanomaterials were measured using dynamic light scattering. Characteristic behaviour, such as aggregation and dispersion was compared each other based on the DLVO (Derjaguin, Landau, Verwey, and Overbeek) theory. Whereas iron nanomaterials showed a strong tendency of aggregation at the pH near point of zero charge (PZC) due to electrostatic attraction between particles, their dispersions became dominant at the pH which was higher or lower than PZC. In addition, the behaviour of iron nanomaterials was likely to be more significantly influenced by cations than anions in the electrolyte solutions. Particularly, it was observed that divalent cation influenced more effectively than monovalent cation in electrostatic attraction and repulsion between particles. It was also confirmed that the NOM enhanced the dispersion nanomaterials with increasing the negative charge of nanomaterials by coating on their surface. Under identical conditions, ZVI aggregated more easily than magnetite, and which would be attributed to the lower stability and larger reactivity of ZVI.

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.193-199
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• 2017

In this study, changes of soil properties including soil texture, specific surface area, organic matter content, pH, cation exchange capacity and exchangeable cations content were investigated in response to strong acid or base accident. The properties changed significantly when the soil reacted with 10 M HCl or 1 M NaOH (i.e., when one gram of soil received 50 and 5 mmol of HCl or NaOH), respectively. When the soil reacted with 10 M HCl or 1 M NaOH solution, soil texture changed from sandy loam to loamy sand and specific surface areas decreased from $5.84m^2/g$ to 4.85 and $1.92m^2/g$, respectively. The soil organic matter content was reduced from 3.23% to 0.96 and 0.44%, and the soil pH changed from 5.05 to 2.35 and 10.65, respectively. The cation exchange capacity decreased from 10.27 cmol/kg to 4.52 and 5.60 cmol/kg, respectively. Especially, high concentrations of $Al^{3+}$ or $Na^+$ were observed in acidic or basic spills, respectively, which is likely to cause toxicity to terrestrial organisms. The results suggest that restoration of soil properties, as well as soil remediation, needs to be carried out to maintain the soil function in chemical spill sites.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.4
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• pp.196-203
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• 2004

To understand the geochemical processes in the Han River Estuary, distributions and behaviors of nutrients, dissolved organic matters, and uranium were investigated and analyzed during estuarine tidal mixing in June 2000 and February 2001. The distribution of inorganic nutrients showed very dynamic distributional patterns implying an apparent nitrification process and a concave non-conservative mixing along the salinity gradient. Dissolved organic carbon was high in the upstream region and decreased sharply in the low salinity region of around 5 psu. The 3-D fluorescence characteristic of dissolved organic matter showed two distinct fluorophores in the study area. Biomacromolecules originated mainly from the indigenous biochemical processes and geomacromolecules from terrestrial humic materials. In the study area, the distribution of geomacromolecule showed a concave non-conservative property along the salinity gradient presumably due to the flocculation and removal processes in the estuary. Meanwhile, distribution of the dissolved uranium, mainly in the form of stable uranium carbonate complex, also showed a concave non-conservative property along the salinity gradient in the Han River Estuary. From this study, the removal rate of dissolved uranium in the Han River Estuary was estimated to be about 7.1 ton per year.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.31-35
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• 2008

This survey was conducted to investigate the functional quality characteristics of garlic based on different soil conditions (Pyungan, Maji, Anmi, Yuga, and Songjung soils). The Pyungan, Maji, and Anmi soils from the Danyang area showed high levels of pH, organic matter, available $P_2O_5$, and inorganic components. For the functional compositions of the garlic harvested from the different soil conditions, the Pyungan garlic contained the highest amounts of alliin and total fructan, with 9.2 and 193.3 mg/g, respectively. The Pyungan garlic also showed the highest amounts of total polyphenol and flavonoids, with 146.5 and 123.5 mg/100 g, respectively. Among the garlics from the different soils, the IC50 values by the DPPH assay ranged from 0.28 to 0.32 g/mL, and the $IC_{50}$ of the Pyungan garlic was 0.28 g/mL. The correlation coefficients between the functional quality of the garlic and the different soil compositions were analyzed. The quality of the garlic was positively affected by the pH and organic matter content (p < 0.01) of the soil. Since the Danyang garlic harvested from the Danyang soil had better functional qualities, these results suggest that the production of garlic in a suitable area for the ecotype is most effective.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.92-99
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• 2002

The study was conducted to investigate the changes of soil properties and evaluation of plant utilization according to the application of compost used with phyllite. At this experiment, the plant cultivation test(lettuce and radish plant) was carried out to know about physico-chemical properties of compost, humus degradarion and stabilization degree, and some effects among rhe treatments were best at 20Mg/ha in PSPC 10(Phyllite, Saw dust, Pig manure Compost) plots and ar 10Mg/ha in PSPC 20 treatments, respectively. The EC value was high in the compost. Therefore the EC was appeared more than 2ds/m at the applied 40Mg/ha with compost. And in case of lettuce, Avail.-$P_2O_5$ and EC were more increased than in the radish plots, highly. In contrast, in case of radish, Toral-N, Total-C, and EC contents were decreased after plant cultivation. That is, it could know that radish was fond of absorprion of nitrogen. Also, BD values of soil physical properties were decreased according to increasing of phyllite addition ratio, however water holding capacity(WHC) was increased. The plant test had not been darnaged through the application of compost used with phyllite in soil and there had not been worse on changing of soil physico-chemical properties. Consequently, phyllite composts have been thought on agricultural utilized possibility.