환경오염원으로서 Benzoate에 노출된 Acinetobacter sp. KS-1의 생존과 형태변화

송승열,오계헌 순천향대학교 기초과학연구소 2002 순천향자연과학연구 논문집 Vol.8 No.2

The purpose of this work was to investigate the survival and morphological changes of Acinetobacter sp. KS-1 when exposed by benzoate as an environmental stressor. The strain KS-1 was isolated from environmental samples around hospitals and could utilize benzoate as the sole source of carbon and energy. Strain KS-1 was examined the physiological and biological characteristics. Physiological analysis using BIOLOG GN2 MicroPlate system was performed to identify the strain, which could be assigned to genus Acinetobacter and designated as Acinetobacter sp. KS-1. Microscopic examination of the strain revealed Gram-negative and short rod cells. Survival of Acinetobacter sp. KS-1 cells was examined in different concentrations of benzoate. Survival of the KS-1 cell had less effect on the concentrations of 10 mM, 100 mM, or 500 mM of benzoate, whereas significant decrease of survival rates was measured at 1 M benzoate. Scanning electron microscopy was used to examine the morphological changes of Acinetobacter sp. KS-1 cells depending on the different concentrations of benzoate. However little morphological changes of the cells were observed in this experiments.

진화계획법(EP)을 이용한 산업체 열병합발전시스템의 일간 최적운전계획

류승헌,김규호 永同大學校 1998 硏究論叢 Vol.4 No.1

본 논문에서는 진화계획법(Evolutionary Programming, EP)을 이용하여 산업체 열병합발전시스템의 일간 최적운전계획을 수립하였다. 최적운전 대상 열병합발전시스템은 축열조와 전기저장장치를 포함하는 복잡한 시스템을 선택하였다. 일간 최적운전계획은 산업체의 열부하와 전기부하를 공급하는데 필요한 일간 총 에너지비용을 최소화하도록 수립하였다. 에너지비용 계산시 열병합발전시스템의 연료비 뿐만 아니라 산업체의 전기비용까지 고려하였다. 실계통 시뮬레이션을 통하여 복잡한 열병합 발전시스템의 일간 최적운전계획을 진화계획법을 이용하여 신속하게 수립할 수 있음을 입증하였고, 동적계획법에 의한 최적운전계획 결과와 비교함으로써 그 정확성을 검증하였다. This paper presents the establishment of an optimal daily operation scheduling for the industrial cogenertion system using EP(Evolutionary Programming). The industrial cogeneration system has both thermal storage tank and electrical storage facility. The minimum energy cost for thermal and electrical loads is calculated through optimal daily operation scheduling. The total energy cost includes both fuel costs and electrical rates imposed to the industry. Through the real system simulation, it is verified that the optimal operation scheduling can be established fastly and accurately by the use of EP.

저주파음에 의한 자리돔, Chromis notatus의 청각 능력 : 청각 문턱치

이창헌,서익조,오승훈,김병엽,서두옥,김동근 제주대학교 해양과환경연구소 2001 해양과환경연구소 연구논문집 Vol.25 No.-

In order to obtain the fundamenal data about method of luring fish schools by underwater sound, this experiment was carried out to investigte the auditory threshold of coralfish Chromis notatus which was on the coast of Jeju island by heartbeat conditioning technique using pure tones coupled with a delayed electric shock. The coralfish could hear a sound in the frequency range from 80 ㎐ to 800 ㎐. The mean auditory thresholds of coralfish at the frequencies of 80 ㎐, 100 ㎐, 200 ㎐, 300 ㎐, 500 ㎐ and 800 ㎐ were 100 ㏈, 99 ㏈, 91 ㏈, 88 ㏈, 96 ㏈ and 114 ㏈, respectively. As the frequency became higher than 300 Hz the auditory threshold increased rapidly.

소독제 과산화수소에 노출된 Legionella pneumophila의 생존력

송승열,오계헌 순천향대학교 기초과학연구소 2000 순천향자연과학연구 논문집 Vol.6 No.2

Survival of L. pneumophila exposed by hydrogen peroxide as a disinfectant was monitored. Initially morphological and physiological characteristics were examined. The strain was small Gram-negative cocco-bacillus and could not degrade carbohydrate. Survival of L. pneumophila was examined in the buffered charcoal yeast extract medium containing 0-5% hydrogen peroxide. The survival rates of cells decreased with increasing concentrations of hydrogen peroxide. The growth of L. pneumophila was significantly inhibited by the exposure of hydrogen peroxide. When the strain was treated with >0.01% hydrogen peroxide, the cells could not grow on the medium. Survival rate of cells decreased when trated with >0.01% of concentrations of hydrogen peroxide. Time-survival studies showed that exposure of L. pneumophila cells to 0.3% hydrogen peroxide resulted in at least 80% killing after 90 min and not detected the survivors at 120 min. No cells were grown at the concentrations of 1%> hydrogen peroxide. As the result, hydrogen peroxide suggested a good candidate for the control agent of L. pneumophila.

난관 소통성의 진단에 있어서 초음파 검사와 진단적 복강경 및 개복술의 비교

이승연,채규정,나미옥,이정헌,류철희,김종덕 대한산부인과초음파학회 2000 대한산부인과초음파학회지 Vol.2 No.2

대호 간척기 토양의 염농도별 밭작물의 염해 평가

이승헌,류순호,설수일,안열,정영상,이상모 江原大學校 附設 環境硏究所 2001 環境硏究 Vol.18 No.-

This study was carried out to obtain the basic data for selecting the applicable crops in reclaimed land during desalinization period. A pot experiment was conducted with 5 different electrical conductivities of the saturated extracts (ECe 1, 3, 9, 14, and 16 dS·m^(-1)) of soils taken from the Dae-Ho reclaimed tidal lands. Eight crops (Chinese cabbage, radish, tomato, red pepper, buckwheat, soybean, sesame, and green perilla) were grown for 37days. Plant height and number of leaves were surveyed on 2 and 4 weeks after seeding, and on harvest time (5 weeks). After harvest, dry weights of harvested crops were measured and soil chemical properties were analyzed. Emergence rates of crops were comparatively high except sesame. For sesame, there was no emergence at ECe over 3 dS·m^(-1). Growth and dry weight decreased significantly as increasing ECe. The ECe which decreased 50% of dry weight index were 14.2 dS·m^(-1) for radish, 11.4 dS·m^(-1) for Chinese cabbage, 10.2 dS·m^(-1) for tomato for red pepper, 8.9 dS·m^(-1) for buckwheat and green perilla, 8.6 dS·m^(-1) for soybean, and 8.9 dS·m^(-1) for tomato. At higher ECe that start the growth inhibition, increasing 1 dS·m^(-1) in ECe, 7.7, 6.5, 5.9, 5.6, 5.2, and 4.9% of dry weight decreased for buckwheat, green perilla, Chinese cabbage, radish, soybean, and tomato (red pepper), respectively. The critical value of ECe for crop survival except sesame was 15.4~23.1 dS·m^(-1).

나프탈렌슬폰산 축합물계와 말레인산 공중합체계 콘크리트용 유동화제가 첨가된 시멘트 현탁용액의 거동

노재성,류호석,조헌영 忠南大學校 産業技術硏究所 1994 산업기술연구논문집 Vol.9 No.1

The behavior of adsorption, the variations of zeta potential, the behavior of sedimentation in the cement suspensions added with Naphthalene Sulfonated Formaldehyde Condensate (β-NSF) and Maleic Anhydride Copolymer (MA) were investigated. Also the variations of mini slump, the time evolutions of mini slump and the setting times of the cement pastes fluidity with β-NSF and MA were tested. From this research, it is cleared that β-NSF has a strong effect on the fluidized of the cement paste and MA affects to keep the fluidity of the paste for a long time.

시효처리와 마모체가 치과용 콤포짓트 레진의 마모에 주는 영향

김승헌,임범순,문현정,이용근,김철위 大韓齒科器材學會 2001 대한치과재료학회지 Vol.28 No.4

Over the last decade, the use of posterior resin composites has grown considerably. Wear resistance of restorative materials is important for clinical longevity, esthetics, and resistance to dental plaque. The purpose of this study was to evaluate the effect of artificial saliva and 75% ethanol solution on the wear resistance of composite resins by measuring the amounts of wear, and compare the effect of antagonistic materials on the wear resistance of composite resins. Four universal composite resins (Z100, Aelitefil, Spectrum, and Unifill F) and two condensable composite resins (Surefil and Synergy Compact) were measured. Cylinder type specimens were light-cured for 40 sec on the wear surface, and 20 sec on each side surface. The surface for wear testing was polished by 600 grit SiC paper. Three different antagonistic materials (600 grit SiC paper, amalgam, and procelain) were used as an antagonist for 2-body wear test. After speciments were aged in 37℃, artificial saliva and 75% ethanol solution for specific periods (1 day, 1 month and 2 month), 2-body wear testing was performed by the FRP-2000 friction tester with applying 500 g load (80 kPa) to the specimen. The wear test was performed for 10 min and 30㎖ distilled water was used as lubricant. Amount of wear was measured by microscopic measuring device of Micro Hardness Tester in 0.1㎛ scale. There was significant difference in wear resistance of composite resins (p<0.05). Composite resins with filler content below 59 vol.% showed higher wear resistance that composite resins those with filler content above 62 vol.%. In composite resins from 1 day to 1 months (p<0.05). On the contray, the wear amounts of groups which filler fraction were above 62 vol.% did not show any significant differences with increasing aging period (p>0.05). In 1 day aged groups, the wear amounts of the groups aged in 75% ethanol solution were more than those of the groups aged for 1 month (p=0.045) and Spectrum group aged for 2 month (p=0.006). Amounts of wear were significantly decreased with changing antagonist from 600 grit SiC paper to amalgam or porcelain (p<0.05).

오염기름 제염에 있어 초임계 이산화탄소의 사용 타당성 연구

박승현,박광헌 慶熙大學校 材料科學技術硏究所 1998 材料科學技術硏究論集 Vol.11 No.-

The main object of this study is a possible use of supercritical fluid in decontamination of contaminated mechanical parts and dresses used in nuclear power plants. Supercritical CO_(2) is a good solvent for cleaning these materials, since it has a powerful ability of penetration to unreachable places and high solubility of oils. And the solubility changes dramatically according to the pressure change, so contaminants can be collected without making any secondary waste. In this study, solubility and removal efficiency of pure oil, gear oil, and grease were measured using supercritical CO_(2) dry cleaning method. The solubility of several oils was shown to increase with pressure ranging from 80 to 200 bars. The removal efficiencies of oil in cleaning mothods using water and that using perclorethylene were compared to dry cleaning with supercritical CO_(2). Oils were removed over 99% in supercritical CO_(2) and in percloroethylene ; however, most of oil was remained in the case of water washing at 60℃. In nuclear power plants, main components of radioactive wastes to be removed are Cs and I. Cs and I were completely removed when we used the water washing method, while percloroethylene and supercritical dry cleaning method couldn't remove Cs and I. To eliminate these components, we used modifier, i.e., a mixture of ethanol and pure water. The results show that removal efficiency of Cs and I in supercritical CO_(2) greatly increases with addition of ethanol and pure water. If this technique becomes materialized, there will be no or less secondary waste for decontamination of contaminated parts and dresses, resulting in more environmentally clean nuclear power plants.

4개 간척 지구에 분포하는 식생과 토양 염류농도

이승헌,지광재,안열,노희명 한국환경농학회 2003 한국환경농학회지 Vol.22 No.2

토양 제염이 토양 화학성 변화와 식물 분포에 미치는 영향을 분석하여 간척농경지의 효율적인 관리방안에 대한 기초자료를 확보하고자 본 연구를 실시하였다. 방조제 체절전후 자연식생이 존재하는 9개 지점에서 식생분포 특징을 조사하고 2개 지점에 대해서는 토양과 식생가의 관계를 검토하였다. 9개 조사지점에서 11목, 14과, 46속, 49종, 8변종, 1품종등 총 58종류의 식생분포가 관찰되었고 자연상태를 잘 유지한 대호 식생보전구와 석문 국가공단 예정 부지에서의 출현종수가 다양하게 분포하였으며 해수를 유통시키고 있는 홍보지구나 만경강, 동진강 하구의 식생은 10 정도로 단순하였다. 9개 조사지점에서 가장 빈도가 높게 출현한 종은 벼과, 명아주과, 국화과에 속하는 나문재(Suaeda asparagoides (Miq.) Maakino), 객개미취(Aster tripolium L.), 갈대(Phragmites australis Trin.), 해홍나물(Suaeda maritima Dum.), 칠면초(Suaeda japonica Dum.), 천일사초(Carex scabrifolia Steud.) 토양에서 염류(Saline)토양으로 그리고 최종적으로 일반 토양으로 변화하였다. 명아주과의 식생은 염도(ECe)가 30 dS/m 전후인 토양에서 출현하여 10 dS/m까지 지속되고, 20dS/m전후에서 객개미취, 산조풀, 사데풀 등이 출현하였으며 10 dS/m 이하에서는 일반육상에서 볼 수 있는 식생종들이 출현하였다. 그러나 토양제염과 동시에 식생의 천이가 일어나는 것은 아니며, 외부에서 종자 등의 식물이 유입될 확률이 있어야하므로, 초기간척지의 식생을 조기에 정착하기 위해서는 토양검정을 통해 적정 염도에서 정착할 수 있는 식생의 인공식재 내지 종자 산파를 통해 촉진시키는 것이 효과적일 것으로 판단된다. This research was conducted to present reference data to be used as newly reclaimed tidal land management. We investigated vegetation succession at 4 reclaimed/reclaiming project areas and discussed relationship with soil and vegetation through investigation and analysis soil chemical characteristics at 2 areas. 14 families 58 kinds were investigated. Vegetation were various at Dea-Ho conservation plot and Seok-Mun National Industrial Area which are maintaining naturally. Vegetation were simple at Hong-Bo and Dongjin and ManKyong river areas which effected sea water. Common species that were investigated at 9 sites were Suaeda asparagoides, Aster tripolium, Phragmites australis, Suaeda maritima, Suaeda japonica, Carex scabrifolia. As soil desalinization progressing, soil classified at first saline-sodic soil, the next saline soil and then normal soil. Chenopodiaceae revealed at about 30 dS/m of soil W e and existed to 10 dS/m of soil ECe. At about 20 dS/m of soil ECe, Aster tripolium, Chlamagotis epigeios, and Sonchus brachyotus revealed and then non halophytes and commom plants at inland revealed at low soil ECe of about 10 dS/m However it was not to progress vegetation succession and soil desalinization at the same time, owing to input of seeds or plants etc from out-ecosystern So for promotion of vegetation at newly reclaimed tidal land, we proposed that it was very effective to plant artificially halophytes or suitable species through soil test.