수돗물중 異臭味에 關한 硏究

김형석,이기태 慶熙大學校 1995 論文集 Vol.24 No.-

The taste and odor in city tap water could be a reason of discomfort by citizen. Even though the concentration of odor substances is trace amount in drinking water, human can detect with sensory system easily. The sources of taste fund odor come from anthropogenic activity and natural origin. Industrial wastewater could contain chemicals and chlorine taste comes from disinfection process during drinking water treatment. Natural sources are the algae and Streptomyces tendae which produce geosmin and 2-methylisoborneol. The numbers of actinomycetes in river water were found to increase coincidentally at the onset of spring. When more than one hundred actinomycetes isolates from water samples were tested for their ability to produce geosmin and 2-methylisoborneol(2-MIB), the majority were able to produce one of both of these odorous compounds. Cyanobacteria also could produce geosmin or 2-methylisoborneol and produce musty-odor. Gas chromatography/mass spectrometry(GC/MS) analyses indicated that volatile fractions of earthy/musty odor compounds are geosmin and 2-MIB. In the water purifying plants algae would make earthy and musty odor. In Japan 1,750 person were complained about the tap water odor. The area of odor problem are related with eutrophication, where the total phosphorous is more than 0.02㎎/L and total nitrogen is more than 0.6㎎/L. The odor of 2-MIB is produced by Phormidium tenue, Oscillatoria tenuis, and geosmin producing algae is produced by Anabaena macrospora and Anabaena spiroides var.crassa. Those 4 algae contain not only chlorophill, but phicocyanin. The detection method of geosmin and 2-MIB is difficult when sample is analyzed directly in GC, so we need to concentrate the sample in advance. Purge and trap method is one of the effective method. Authors tried to detect the geosmin and 2-MIB in drinking water by extracting the water sample in purge and trap methods and SPME(solid phase micro extraction) method was applied to detect benzene, toluene, and xylene. There are two kinds of sources for odor substances. One is fungus, e.g., Streptomyces tendae. Penicillium expansum, Actinomycetes, which produce geosmin. The other one is blue-green algae, e.g., Phormidium tenue, Oscillatoria limnetica, which produce 2-methylisoborneol. We could detect the geosmin and 2-methylisoborneol standard solution with gas chromatograph. The volatile organic coumpounds, BTEX, were detected with SPME(solid phase micro extraction) method.

水質汚染에 의한 貝類中 重金屬汚染에 관한 國際的 硏究

김형석,김덕만,이기태,Chiba Momoko,Teramoto Keiko 한국환경독성학회 1994 환경독성보건학회지 Vol.9 No.2

The accumulation of heavy metals including Cd, Cu, Mn, Zn and Pb in various organs of shellfish which is the reasonable bio-indicator for hazardous substance contamination on lotic habitats with relatively limited mobility through waterbody was studied. Meretrix petechialis, Scapharca broughtonii, and Scapharca subcerenate from West Coast of Korea and Osaka Bay of Japan were selected to compare heavy metal contamination in adduct muscle, foot muscle, gill, mantle, and visceral organ of marine shellfish. Semisulcospira spp. from various area include West Coast of Korea and Han river were analyzed to compare heavy metal concentration in whole tissues between marine water and fresh water. A regional differences among Hong-chun, Kang-chon, Keum-nahm, Kah-pyung, Seo-rak, and Pal-dang of heavy metal concentration in Semisulcospira gottche was compared. There are significantly differences in mean concentration of Cd, Cu, Mn, Zn, and Pb among organs and species of M. petechialis, S. broughtonii, and S. subcerenate (ANOVA -F=60.31, p<0.001; F=36.88, p<0.001; F=27.78, p<0.001; F=9.39, p<0.001; F=2.91, p<0.001, respectively). The highest mean concentration of Cd with 0.680ppm was observed in gill and the lowest mean concentration of Cd with 0.082ppm was observed in foot muscle. The mean concentration of Cd with 0.349ppm in S. broughtonii was significantly different from other two species with 0.255 and 0.175ppm. Both Cu and Mn were highly accumulated in gill and mantle compare to other organs. Both gill and mantle had significantly different mean Cu concentration with 4.937 and 4.950ppm, respectively compare to both adduct muscle and foot muscle with 2.129 and 2.029ppm, respectively after Duncan's Multiple Range Test. The mean concentration of Cu with 1.900ppm in S. broughtonii was significantly lower then those of other two species. Both Zn and Pb were highly accumulated in gill compare to other organs. The mean concentration of all tested heavy metals except Cu in S. broughtonii were significantly higher than those of other species. There are significantly differences in mean concentration of all tested heavy metal except Cd between whole tissue of marine Semisulcospira spp. and fresh water Semisulcospira spp. Fresh water Semisulcospira spp. had high mean concentrations of Mn, Zn, and Pb while marine Semisulcospira spp. had higher mean concentrations of Cu. The mean concentrations of all tested heavy metals except Pb in Semisulcospira gottche from various area in Han River was significantly different among sites. The mean concentration of Cd in S. gottcheu from Hong-ehun, Cu in S. gottcheu from Kang-chon and Kah -pyung, Mn in S. gottcheu from Kah-pyung and Paldang, and Zn in S. gottcheu from Pal -dang was higher than those of other sites.

Effect of Nitrogen on the Growth of Scenedesmus maximus

Rhie, Ki-Tae,Choo, Kyung-Sil 慶熙大學校 1997 論文集 Vol.26 No.-

질소가 담수 녹조류인 Scenedesmus maximus의 세포분열, 건중량, 광합성율과 암호흡율 등에 미치는 영향을 연구하고 세포의 질소 흡수율을 고찰하였다. 접종후 9일 이후에 각 질소처리군 간의 평균 세포수는 유의한 차이를 보였다. 접종 후 15 에 0.94mM의 질소를 처리한 군에서의 평균세포수는 가장 높아 3.942±0.743 × 10 exp (6) cell· ml^-1으로 관찰되어 과도한 질소는 세포분열의 억제효과가 있는 것으로 나타났다. 상대성장 율의 경우에도 각 질소처리군간 유의한 차이가 나타나 접종후 3일에 0.94 mM의 질소처리 군에서 가장 높게 나타났다. 세포건중량은 9.35 mM의 질소처리군에서 높게 나타나 접종 후 9,12 및 15일에 각각 0.093±0.006, 0.098±0.020 및 0.096±0.013 mg·10^-6cell 으로 관찰되어 세포의 충실도에 기여된 것으로 간주 되었다. 광합성율에 있어서 9.35 mM의 질소를 처리한 군에서 높게 나타나 접종후 3일에 0.342±0.242 μO_2ml^-1h^-1 로 광합성 기구에 충분한 질소를 공급할 수 있는 농도로 간주되었다. 더 높은 농도의 질소처리는 광합성율의 증가에 도움이 되지 않은 것으로 나타났으며 오히려 감소하는 경향도 보였다. 질소의 흡수율에 관한 고찰에서, 0.94 mM을 처리한 경우 시간의 경과에 따라 배지의 잔류 질소 농도가 두드러지는 감소를 보여 접종 후 15일에는 잔류질소가 검출되지 않았다. 질소를 각각 0.94, 9.35, 18.70, 28.05 및 37.40mM 로 처리한 경우 배지 내 녹조류의 질소 흡수율은 각각 0.011±0.013, -0.122±0.033, -0.001 ± 0.249, -0.903±0.142 및 -1.938±0.367 mmol·ml^-1·day^-1으로 나타나 적정한 농도의 질소유입은 Scenedesnus maximus의 과다성장을 질소원의 고갈로 인한 과다성장의 조절이 자연적으로 일어날 수 있으나 수생환경으로의 과다한 질소 유입은 S. maximus의 지속적인 과다 성장을 유도한다고 사료된다.

The Effect of Silicon Ion on Proliferation and Osteogenic Differentiation of Human ADSCs

( Ki Joo Kim ),( Young Joon Jeon ),( Jung Ho Lee ),( Sang Tae Ahn ),( Soo Hong Lee ),( Dong Woo Cho ),( Jong Won Rhie ) 한국조직공학과 재생의학회 2010 조직공학과 재생의학 Vol.7 No.2

Tissue engineering requires biopolymer scaffolds with compressive strength. Bioglass produces the compressive strength required of new scaffolds, and ionized Bioglass improves cell proliferation and differentiation. Ionized Bioglass contains phosphorous, sodium, calcium, and silicon ions, but the contributions of single ions or ion complexes to the cellular effects of Bioglass have not been determined. Here, we examined the effect of silicon on cell growth and differentiation. Culture medium containing 2, 4, 6, 8, and 10 μM silicon ions was produced in a chemical neutralization reaction by mixing a sodium silicate solution and hydroxychloride, and human adiposederived stromal cells (ADSCs) were cultured in the silicon-containing medium. Cell growth was followed for 9 daysin culture, using a Cell Counting Kit-8 assay. Osteogenic differentiation was examined by alizarin red S staining and RT-PCR for osteogenic genes at 10, 20, and 30 days of culture. The proliferation of human ADSCs cultured in medium containing 2 or 4 μM silicon was significantly greater than that of ADSCs in the control medium. Differentiation of human ADSCs was increased by supplementation of the differentiation medium with 2 μM silicon. This work demonstrates that 2 μM silicon accelerated proliferation and osteogenic differentiation of human ADSCs.

광덕산 식물체의 중금속 함량에 관한 연구

이기태,최한수 한국환경독성학회 1999 환경독성보건학회지 Vol.14 No.4

Heavy metal accumulation in living organisms through food-wed can give serious damage on physiological responses for vital activities. The initiation of heavy metal supposed to begin from the bio-accumulation of plants. To establish basic data for heavy metal contents in plants at the area without artificial contamination, both woody and herb plants at Mt. Kwang-Duk were studied. The contents of heavy metals in various organs of plants were analyzed by ICP. The range of heavy metals in plants for Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ph, Se and Zn were 1.019~257.200 ppm, 0~2.929 ppm, 0~0.079 ppm, 0~0.054 ppm, 0.023~3,007 ppm, 0~1.997 ppm, 2.031~148.500 ppm, 1.069~51.320 ppm, 0~126.900 ppm, 0.708~4.927 ppm and 0.846~4.949 ppm, respectively. The amount of heavy metals in plants are much less than that of soil except some species. In woody plants, it was detected that the metal contents of leaves were higher than that of stems especially in case of Al and Fe with statistical significance. There were significant differences between shoots and roots of herb plants in metal content of Al, Co and Fe. Those metals have more accumulated in roots comparing with shoots. Some species of plants had shown the difference tendency of heavy metal accumulation. Generally, most species had not exceeded over twice of mean value each other, and had various difference according to the kinds of heavy metals.

조류의 Methylglyoxal과 인 Stress 연구

이기태 한국환경독성학회 1998 환경독성보건학회지 Vol.13 No.2

Effects of phosphorous (P) and methylglyoxal (MG) on the cell number, dry weight, chlorophyll content, photosynthetic and respiratory rate, phosphate uptake and protein content of green algae(Scenedesmus obliquus) were studied. The algal cell number from the medium treated with 0.5~1.0 mM of MG at 1/2 P or 1/4 P concentration was significantly lower than those of algae treated with full strength of phosphrous in medium. The inhibitory effect of MG on algal cell division was enhenced at low concentration of phosphorous in medium. At the beginning of logrithmic phase of algal growth, the mean dry weight of algae from the medium without MG-treatment in 1/2 P media was significantly higher than that of algae treated with MG. After logrithmic phase of growth cycle, the mean dry weight of algae from the medium with 1.0 mM of MG-treatment in 1/4 P media was significantly lower than that of algae treated with or without MG. At logrithmic phase of algal growth, there were significant differences in the chlorophyll content among all groups of tested algae with various concentrations of P and MG. At 15 days after inoculation, the mean chlorophyll content per algal cell from the media without MG-treatment in 1/21? was significantly higher than that of other cells from MG-treated media. The adverse effect of MG at concentration of 0.5~1.0 mM in 1/2 and 1/4 P media on photosynthetic rate was observed. The mean photosynthetic rate of algal cell without P and MG treatment at 15 days after inoculation was significantly higher than that of MG-treated algae. After logarithmic phase, the algal cell treated with 0.5 mM of MG with full strength of phosphorous showed significantly high respiratory rate than that of other cell groups. There were significant differences in mean phosphate uptake rate among all groups of Scenedesmus obliquus at logarithmic phase. At 12 days after inoculation, phosphate uptake rate per each algal cell from the basic media without MG and P treatment was rapidly reduced which shows early introduction to stationary phase. Anionic protein content in algae from basic media with 0.5 mM of MG treatment was significantly increased at the end of logarithmic phase. The highest anionic protein content was observed in cell at full strength P with 0.5 mM of MG treatment. Anionic protein content in algae from basic media without MG treatment was significantly lower than that of other groups of algae through all stages of life cycle. During logarithmic phase of algal growth, cationic protein content in cell from 1/2P media treated with 0.5 mM of MG was significantly higher than that of other groups of algal cell.

Preparation and Evaluation of PLGA-Silica Scaffold with Human Adipose-Derived Stromal Cells for Bone Tissue Engineering

( Ki Joo Kim ),( Jung Wan Oh ),( Guang Zhen Jin ),( Jung Ho Lee ),( Deuk Young Oh ),( Hyun Wook Kang ),( Hwan Mook Kim ),( Soo Hong Lee ),( Dong Woo Cho ),( Sang Tae Ahn ),( Jong Won Rhie ) 한국조직공학과 재생의학회 2010 조직공학과 재생의학 Vol.7 No.3

One of the main goals of bone tissue engineering is to develop suitable bio-acceptable materials for bone graft substitutes, especially for filling large defects. In the present study, porous poly(lactic-co-glycolic acid) (PLGA)-silica scaffolds were successfully fabricated using indirect microstereolithography technology. The scaffolds were evaluated in vitro by analyzing their microscopic structure, porosity, and stiffness. Following in vitro osteogenic induction, human adipose-derived stromal cells (ADSCs) were seeded in the scaffolds, and the expression levels of osteocalcin mRNA and collagen type I protein were detected by RT-PCR and Western blotting, respectively. We further evaluated the osteoinductive efficacy of the scaffolds in vivo by implanting human ADSC-seeded scaffolds into athymic mice. The silica particles improved the mechanical strength of PLGA scaffolds, and the PLGA-silica scaffolds exhibited better osteogenic potential in vitro than conventional PLGA scaffolds. The in vivo osteogenic events after scaffold implantation were consistent with those observed in vitro. This study demonstrates the potential of PLGA-silica scaffolds seeded with human ADSCs as a useful tool for bone tissue engineering.

구리와 Methylglyoxal에 의한 조류의 성장 및 인 흡수

이기태,이기성 한국환경독성학회 1999 환경독성보건학회지 Vol.14 No.4

Effects of various concentrations of copper in solid fibrous form and methylglyoxal (MG) on phosphorus uptake and growth change of green algae Scenedesmus obliquus were studied. There was significant differences among cultures treated with various concentrations of copper and MG in growth of algae with parameters of cell numbers, photosynthetic rate and cellular morphology, and phosphorus uptake by cell. When the copper in media is treated with 25mg or 50mg per 100 ml of Bristol solution, the mean cell number of algae was 15.642 x 10^(6) cells· ml^(-1) and 12.986 x 10^(6) cells·ml^(-1), respectively, while those of algae in culture without copper was 18.486 x 10^(6) cells - ml^(-l). The mean cell area of 2450 μm², 1894μm² and 1697μm² in basic media, basic media with 25 mg of copper and basic media with 50 mg of copper was showed the inhibitory effect of copper on algal growth. The algal growth was stimulated by MG when the culture was treated with 25mg of copper or without copper, while it was inhibited when the culture was treated with 50mg of copper. It was considered that there was significant interaction between copper and MG on algal growth. The phosphorus concentration in algal medium treated with 25 mg or 50 mg of copper was 29.435 ppm and 26.224 ppm, respectively, while those of algae in culture without copper was 52,8 ppm, which shows that the application of copper in algal medium can prevent the availability of phosphorus to algal cell.

HVSR 방법을 이용한 지표 하부 지질구조 영상화

권기백(Ki Baek Kwon),안병석(Byeong Seok Ahn),허다빈(Dabeen Heo),강태섭(Tae-Seob Kang),임호빈(Hobin Lim),한재승(Jaeseoung Han),김영희(YoungHee Kim),이준기(Junkee Rhie),김광희(Kwang-Hee Kim),이진한(Jin-Han Ree) 대한지질학회 2021 대한지질학회 학술대회 Vol.2021 No.10

배경잡음의 수평 대 수직성분 스펙트럼 진폭비(Horizontal to Vertical Spectral Ratio; HVSR)를 이용하여 경주시 내남면 일대의 천부 지질구조를 영상화하였다. 2016 경주지진 원인 단층 특성 조사를 위해 2020년 11월부터 약 한 달간 67개의 3성분 단주기 지오폰으로 구성된 배열을 운영하였으며, 지오폰 배열(Naenam Fault Array; Lim et al . 2021)은 내남단층의 주향에 수직하도록 설치되었다. 각 지오폰의 샘플수는 초당 2 ms으로 설정하였다. 지오폰 배열을 구성하는 지오폰 간 평균 거리는 약 200 m이며, 총 길이는 약 15 km이다. HVSR 분석에서 자연지진이나 인위적인 원인에 의하여 발생하는 특정한 신호의 영향을 최소화하기 위하여 야간의 시간대에 일시적인 진폭을 제외한 2시간 동안의 상시미동 자료를 이용하였다. HVSR 곡선을 통해 확인 가능한 공진주파수는 각 지오폰 하부에서 강한 임피던스 대비가 발생하는 기반암과 상부 퇴적층 사이 경계면의 깊이와 관계있으며, 이를 통해 퇴적층의 깊이를 추정할 수 있다. HVSR 계산 결과 대부분의 관측소에서 공진주파수로 추정되는 단일 피크가 확인되었으며, 단층 주변에 위치한 일부 관측소에서는 공진주파수가 저주파수 대역에서 나타나는 경향을 보였다. 공진주파수로부터 퇴적층의 두께를 추정하기 위하여 배경잡음 표면파 분석을 통한 퇴적층의 전단파 속도를 결정하였다. 각 지오폰 위치에 대하여 반무한 기반암 상부의 퇴적층으로 이루어진 1층 속도 모델을 구성하였다. 각 지점의 속도 모델에 대하여 합성 HVSR 곡선을 계산하였다. 배경잡음 자료를 이용하여 계산된 HVSR 곡선과 속도 모델의 신뢰성 검증을 위해 합성 HVSR 곡선과 비교하였다. 대부분의 지점에서 가정한 속도 모델은 관측한 배경잡음 HVSR 곡선을 적절하게 근사하였다. 지오폰 배열을 따라 각 지점의 1층 속도 모델을 연결하여 퇴적층 두께 변화를 나타내는 단면을 구성하였다. 그 결과, 양산단층 및 덕천단층 인근을 포함한 일부 지역에서 최상부 퇴적층이 상대적으로 깊은 경향을 보인다. 단층 주위에서 깊은 퇴적층의 두께는 주요 단층들의 주향이동에 수반된 경사이동 성분에 의하여 야기된 것으로 추정된다.

위험성평가를 통한 PEMFC 시스템 안전성 확보

김현기(Hyeon-ki Kim),홍성철(Sung-chul Hong),서두현(Doo-hyoun Seo),김태훈(Tae-hoon Kim),이광원(Gwang-won Rhie),노태호(Tae-ho No),이동민(Dong-min Lee),신단비(Dan-bee Shin) 한국가스학회 2021 한국가스학회 학술대회논문집 Vol.2021 No.11