• 한국지하수토양환경학회지:지하수토양환경
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• 제15권4호
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• pp.39-45
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• 2010

In order to treat paddy soils contaminated by Pb, Cd, and As near the abandoned mine, $H_2PO_4$ was used for stabilization of Pb ($PO_4$/Pb mole ratio of 2/1). In addition, $CaCO_3$ and $FeSO_4$ were used as stabilizers for treating Cd and As (2% w/w), respectively. Leaching tests were conducted with artificial rain in the column to assess the heavy metal stabilization efficiency. The mass of heavy metals in the effluents passed through the columns were analyzed. The remaining heavy metals in the soils were also analyzed as Korean soil standard method, phytoavailability test and sequential extraction test. Lead in the effluent was not detected when $H_2PO_4$ was used as a stabilizer. This result suggests that $H_2PO_4$ is efficient for Pb stabilization. In addition results of sequential extraction scheme suggest that heavy metals are present as residual forms which is not easily extracted.

• 동아시아식생활학회지
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• 제4권3호
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• pp.59-65
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• 1994

이 실험에서는 소의 유즙에 있는 성장인자를 세포배양을 통해 확인하고 크로마토그래피를 사용하여 분리 정제하였다. 5%의 우유를 포함하는 배지를 FBS(fetal bovine serum)를 포함한 배지와 비교했을때 Africal green monkey kidney cell의 성장 촉진 효과가 비슷하게 나타났으며, 우유의 성장인자를 분리 정제한 결과 FBS배지에서보다 2,000배 이상의 성장 촉진 효과가 나타났다. 이 성장인자는 hydrophobic column(phenyl-sepharose)과 gel-filtration column(sephadex G-100)을 사용하여 분리했으며 그 결과 milk-deriven growth factor는 phenyl-sepharose에서 50% ethylene glycol step에서 용출되므로 hydrophobic protein임이 증명되었고 size exclusion column chromatography로 부터 분자량이 100,000-15,0000 범위의 고분자 물질임이 밝혀졌다. 또한 우유의 성장인자는 매우 다양하며 그중 본 실험으로부터 정제된 물질이 주요 성장인자로 밝혀졌다.

• Journal of the Korean Wood Science and Technology
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• 제36권4호
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• pp.102-108
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• 2008

현재 메인 주립대학에서는 펄프용 목재 성분 중 헤미셀룰로오스 추출 기술에 관한 연구개발이 한창 진행 중이다. 펄프의 수율 향상과 용액 회수에 필요한 유기 및 무기물 사용을 줄이고 새로운 바이오 물질 생산에 필요한 도입부 추가 공정이 연구의 핵심이다. 바이오 물질 중 경제적으로 상용 가능한 에탄올 생산(pilot-scale)에 있어 전 처리되지 않은 기질, 전 처리된 기질 및 펄핑 선 추출액의 화학적 성분분석은 아주 중요한 공정이다. HPLC (High Performance Liquid Chromatography)를 이용한 펄프목재 성분분석 결과, H-column으로 분석한 총 물질수지(total analytical mass balance)는 전 처리되지 않은 칩의 경우 100.6%, 전 처리된 목재 칩은 100.3%, 그리고 펄핑 선 추출액은 81.6%의 결과를 보였다. 한편, P-column으로 분석한 결과, 전 처리되지 않은 기질, 전 처리된 기질, 그리고 선 추출액은 각각, 97.8%, 97.4%, 그리고 80.7%로 나타났다. 총 물질수지가 100%를 넘거나 부족한 수치는 분석해석 중 발생한 약간의 오류로 보인다. 펄프-바이오리파이너리(Biorefinery) 공정을 통해 생성된 기질(substrate) 각각의 정확한 성분분석 결과는 에탄올 상용화 공정에 필요한 중요한 자료가 될 것으로 기대한다.

• 약학회지
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• 제36권3호
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• pp.205-211
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• 1992

A simple dignostic method using Fast Atom Bombardment mass spectrometry was applied to the characterization of green tea flavonols from the eluates of Sepahadex LH-20 column chromatography. From the ethyl acetate extracts, crude mixture of flavonol fraction(Fr.$1{\sim}4$) were separated by the stepwise gradient elution with 30, 45, and 60% aqueous acetone. Procyanidine B analogues were found to be typical constituents of Fr. 1. Main components of Fr. 2 were catechins and gallo-catechins. Fr. 3 contained mainly ester type compounds, catechin-gallates, gallocatechin-gallates with their analogues. Fr. 4 was contaminated with some phthalate esters.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.71-72
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• 2014

Green Frame is a building frame system to construct a column-beam structure using composite precast concrete members. To reduce the cost of producing precast concrete, in-situ production of members is required. However, when the structural members are produced on site, it needs a large space for production. So, "Just-In-Time" production method should be adopted. For Just-In-Time to be realized, the early strength of members should be ensured for them to be transported. Thus, steam curing to secure the early strength is applied in Green Frame. Yet, a large-scale steam curing system is not possible for in-situ production of precast concrete. A smaller steam curing system is needed. In this regard, the study is aimed to develop a new steam curing method applicable to the in-situ production of precast concrete.

• 한국식품위생안전성학회지
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• 제5권4호
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• pp.213-217
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• 1990

커피, 홍차, 녹차중의 카페인 함량을 간단하고 신속하게 정량하는 방법을 검토하였다. 역상계 액체크로마토그래피에 의한 카페인 정량은 메타놀-초산-물(20 : 1 : 79)을 이동상으로 하여 ${\mu}-Bondapak$ C18 컬럼하에서 이루어졌다. 카페인의 검출에는 UV검출기를 사용하여 280 mm에서 행하였다. Sep-Pak alumina A 카트리지를 이용한 간단한 전처리를 통해 효과적으로 카페인의 추출 및 clean-up를 행하였다. 카페인의 첨가 회수율은 95.2~101.3%이었고 분석의 재현성은 상대표준 편차로서 0.10~0.62%이었으며 검출한계는 $0.1;\mu\textrm{g}$/ml이었다.

• ALGAE
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• 제26권2호
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• pp.141-152
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• 2011

The present study describes the morphology, taxonomy, and distribution of species belonging to the diatom genus Rhizosolenia in Korea's marine coastal waters. From September 2008 to February 2010, we collected phytoplankton samples at 30 sites along the Korean coastline and studied them by light and scanning electron microscopy. We found 6 rhizosolenid genera in our samples: Rhizosolenia, Dactyliosolen, Guinardia, Pseudosolenia, Proboscia, and Neocalyptrella. In the present paper, we studied the following rhizosolenid species and compared them with congeners: R. pungens, R. fallax, R. imbricata, Rhizosolenia sp. 1, and Rhizosolenia sp. 2. The morphology of R. pungens exhibits important diagnostic characteristics in its girdle segment structure in the column and in its external process. To distinguish R. fallax and R. imbricata, the most important characteristics are the striation and the velum structure. R. pungens occurred in our samples all along the Korean coast. Only rarely did we find R. imbricata in the samples and at low abundance. We recorded R. fallax, Rhizosolenia sp. 1 and Rhizosolenia sp. 2 for the first time in Korean waters, but they rarely occurred.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.621-625
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• 2007

Oscillating wave amplitude in a bottom-mounted owe chamber designed for wave energy converter is investigated by applying characteristic wave conditions in Korean coastal water. The effects of shape parameters of OWC chamber in a view of wave energy absorbing capability are analyzed. Both experimental and numerical approaches are adopted and their results are compared to optimize the shape parameters which can result in a maximum power production under given wave distribution. The experiment was carried out in a wave flume under 2-D assumption of OWC chamber. In numerical scheme, the potential problem inside the chamber is solved by use of the Green integral equation associated with the Rankine Green function, while outer problem with the Kelvin Green function taking account of fluctuating air pressure in the chamber. Air duct diameter, chamber width, and submerged depths of front skirt and back wall of chamber changes the magnitude and peak frequency of wave absorption significantly.

• 한국식품영양학회지
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• 제13권2호
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• pp.164-170
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• 2000

10 carbamate pesticides were surveyed in domestic and imported green peas, beans, red beans from March 1999 through December 1999. Samples were collected from Gwangju, Mokpo, Suncheon and Yosoo grain markets. This study was performed by post-column ο-phthalaldehyde and 2-mercaptoethanol prior to HPCL fluorophore detection. Pesticides were found in 14 of 80 samples(17.5%). The kinds of pesticide detected in green peas were methomyl, MTMC, carbaryl, those in sesames were oxamyl, carbofuran, carbaryl, 1-naphthol, MIPC, those in beans were oxamyl, MTMC, carbaryl and those in red beans were MTMC, carbaryl. The range of residues detected in green peas, sesames, beans and red beans were 0.002∼0.025ppm, 0.001∼0.469ppm, 0.005∼0.356ppm and 0.017∼0.125ppm, respectively. The most frequently detected pesticides were MTMC(6 times) and carbaryl(5 times), while aldicarb, PHC and BPMC were no detected in all samples. Detection frequencies of carbamate pesticides in imported crops were higher than those in domestic ones except red beans. Only one result of oxamyl residues determined in imported bean was higher than the proposed maximum residue limits of Codex, which was 0.356ppm.

• 한국식품저장유통학회지
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• 제6권3호
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• pp.328-332
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• 1999

떫은감의 총페놀성 물질은 녹숙감에서 3.09%로 가장 높았고, 완숙감에서는 1.51%, 연시는 0.48%로 점차 감소하는 경향을 나타내었으며 가용성 탄닌도 연시에서 현저하게 감소하였다. Acetaldehyde 반응성은 녹숙감에서 추출한 가용성 탄닌이 완숙감의 탄닌보다 다소 높았고, 연시에서 추출한 탄닌은 acetaldehyde와 반응하지 않았다. 탄닌의 함량이 높을수록 acetaldehyde 반응성은 증가하였으며, 각 탄닌성분을 Styragel $10^3$$\AA$ GPC column으로 분획한 결과 과실이 성숙, 연화됨에 따라 탄닌성분은 점차 고분자화 되는 경향을 보였다. 또한 TLC상의 녹숙감과 완숙감의 탄닌성분은 각각 4개의 band를 나타내었으나 연시 탄닌은 2개의 band만 나타내어 탄닌 구성성분의 차이를 보였다.