• Journal of Korea Soil Environment Society
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• v.5 no.1
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• pp.85-96
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• 2000

The purpose of this study was to Investigate the effect of environmental conditions on the degradation of total petroleum hydrocarbons(TPH) in soil. The soil used for this study was sandy loam. Target contaminant, diesel oil, was spiked at 10.000mgTPH/kg dry soil. Moisture content was controlled to 50%, 70%, and 90% of field capacity of the soil. Temperature was controlled to $5^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$. The active degradation of TPH was observed at the moisture contents of 50% and 70% of field capacity, and temperature of $10^{\circ}C$ to $30^{\circ}C$. Degradation rate of n-alkanes was about two times greater than that of TPH. Volatilization loss of TPH was about 2% of initial concentration. Biocide control and no aeration experiments indicated that removal of TPH was primarily occurred by biodegradation under aerobic condition.

• Journal of Life Science
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• v.8 no.1
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• pp.60-66
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• 1998

The mototic and meiotic chromosomal characteristics of ICR mice were investigated with G-and C-banding techniques. For the puposes, the chromosomal preparations were made with the modified air-drying method of Imal et al. Chromosomal analysis using testis could be observed mitotic as well as meitotic chromosomal behaviors, and the centromeric regions of all chromosomes including X chromosome were strongly stained in C-banded preparations. Nineteen autosomal bivalents and a single uniequal terminally associated X-Y bivalent in normal cells were observed during the late prophase and the metaphase of the meiosis I. The mean frequencies of previously dissociated X-Y chromosomes in the primary apermatocytes of the control group were 7.45%, but the frequencies of X-Y dissociation in the alkylating agents-treated group were about 3-4 times higher than that in the control group. Application of C-banding in meiotic stages could be certainly distinguish between vibalent type and univalents type of sex chromosomes.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.1
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• pp.67-77
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• 1999

The biodegradation of algae coagulated with poly aluminum chloride(PAC) was investigated by using the thermophilic oxic process. The compositions of coagulated algae were 83.5% of water content, 24.6% of ash, 32% of organic carbon with in total solid, respectively. In present study, food waste oil was used for the increment of calorie of mixtures in order to accelate the microbial activity. As a result, the maximum temperature of mixtures was higher than $50^{\circ}C$ when the mixing ratio of food oil was over 10%. However the temperature indicated the lower than $50^{\circ}C$ when conditions of no mixing with waste food oil, and 5% of mixing ratio. Therefore, the optimum condition was 10% of the mixing ration at $217l{\cdot}m^{-3}{\cdot}min^{-1}$ of air supply rate. The conversion efficiency of carbon was highest as 92% at the optimum condition. And then water was evaluated from imxture without accumulation at 10% of mixing ratio. The thermophilic oxic process well conducted that is good process for the treatment of waste algae without effluents however it has to consider the retreatment of accumulated aluminum in the reactor.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.69-72
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• 2011

Soil aggregate is a vigorous procedure including soil physical, chemical, and biological processes. Pore space created by binding these particles together improves retention and exchange of air and water. Various researches have reported that the benefits of organic polymers that may increase aggregate stability. The purpose of the study was to determine if a liquid organic polymer mixture has any influence on perennial ryegrass quality or soil aggregation. $Turf2Max^{(R)}$ was applied to two soils as a source of liquid organic polymer. Fine-loamy soil from local Iowa topsoil with 4.0% organic matter was screened and dried. Commercial baseball infield clay, $QuickDry^{(R)}$, was used as the second soil There were three rates of liquid organic polymer (0, 2, and 4%). there was no visual improvement in turf grass color, quality, or growth by using organic polymer. It is possible that aggregate stability increases with use of organic polymer. The aggregate stability study needs to be repeated in the greenhouse and then substantiated under field conditions for these preliminary observations.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.253-257
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• 2002

The time-dependent changes of red pigments production in solid-state plant scale fermentor using barley cultured with Monascus sp., instead of rice which was traditionally used, were investigated in this study. A steady increase in the yield of red pigments in barley occurred between the 3rd and 6th days. The optimized conditions (inoculation volume = 6∼8%, initial pH = 6, air supply = 0.6∼0.8 m) promoted the production of red pigments. Short-time steaming of barley (< 20 min) decreased fungal growth and pigments production due to the insufficient gelatiniza-tion. The optical density of the red pigments under the optimized conditions was 120 at 500 ]nm per gram of barley. In addition, the metabolites from the fermented barley with Monucus sp. showed antibacterial effects against Escherichia coli and Salmonella typhimurium. Barley was shown to be one of the best grain sources for solid-state fermentation with Monascu sp., fur obtaining natural pigments and also functional food materials.

• Proceedings of the KAIS Fall Conference
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• 2012.05a
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• pp.30-32
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• 2012

본 연구에서는 Cu, Mn을 함침 시킨 상용 제올라이트13X 촉매에 CO 산화 전환 반응에 영향을 연구하였다. 촉매 제조는 담지량별로 Cu, Mn을 서로 다른 비율로 물리 혼합하여 상용 제올라이트에 담지하였다. 함침방법은 과잉용액 함침법을 사용하였고, 건조 후 공기분위기에서 소성하여 산화물 형태로 담지하였다. 기본적인 촉매 특성은 X-선 회절분석, 질소흡탈착 등온곡선을 이용하여 기공크기, 기공부피, 비표면적을 구하였으며, FT-IR, 주사현미경, $NH_3$-TPD/TPR, EDX로 특성을 분석하였다. 촉매 산화반응 실험은 고정층 반응기에서 수행하였으며, 외경1/4 inch(내경 4 mm)석영관에 촉매를 중진하고 Gas Chromatograph로 배출가스를 측정하여 Cu-Mn 제올라이트 촉매의 일산화탄소 산화반응을 연구하였다. 일산화탄소 농도, 온도 및 공간속도, Cu-Mn 함량 비율에 따른 산화반응 실험을 수행하여 최적 산화조건과 촉매를 도출하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.10
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• pp.86-92
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• 2013

In studies on an alternative insulating gas of $SF_6$ gas, the section of the alternative gas and an insulation technique to improve its low dielectric strength have been reported, but very few attempts have been made at the dependence of a gas pressure and a gap as well as the medium effect in the alternative gas. The purpose of this paper is to analyze the dependence of the gas pressure and the gap at surface flashover voltage in dry air. The dependence is analyzed based on the medium effect. The medium effect by the gas pressure and the gap can be explained by surface roughness of a solid dielectric and an electrode as well as an electric field which decreases due to the correlation between the collision ionization coefficient and the gap, respectively. In addition, an insulation technique which can fabricate a compact eco-friendly gas insulated switchgear is proposed by the results of this paper.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.43-49
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• 2015

The objective of this paper is to investigate experimentally the effect of the substitution of recycled aggregates under 13mm on the properties of the concrete using coarse aggregate with size of 13~25mm. Recycled aggregate under 13mm were substituted to the concrete ranged from 10% to 100%. To compare the properties with the case of recycled aggregate, crushed stone with smaller than 13mm was also substituted to the concrete by 20% and 40%. Test results showed that increase of recycled aggregate under 13mm resulted in the increase of slump and compressive strength compared with plain mixture, which was made with only aggregate with 13~25mm size. This is due to the dense gradation of aggregate in association with addition of relatively small particle. It is thought that the use of recycled aggregate under 13mm along with 30% contributes to the quality improvement of the concrete made with only 13~25mm aggregate.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.5
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• pp.289-296
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• 2016

The availability of NMP, a solvent used in the manufacturing process of cathode material for lithium ion battery, depends on importation, and the price remains high because of the monopoly of BASF and ISP. For these reasons, most Lithium ion battery manufacturers reuse NMP after recovering it from the exhaust air in the drying process. In Korea, absorption method is mainly used for recovering NMP from the absorption tower using the hydrophilicity of NMP. However, this system has a few disadvantages, such as low purity (80％) of the recovered NMP and 100％ emission due to high water content of the treated gas. In this study, we develop a hybrid NMP recovery system by combining cooling condensation method with concentration method, by which it is possible to obtain an NMP recovery rate of 99.6％, and a high purity (96.1％) of the recovered NMP.

• Journal of the Korea Institute of Building Construction
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• v.12 no.2
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• pp.152-160
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• 2012

The development of building must be accompanied with construction technology and performance of materials. In particular, wet processes have a high level of dependence on manpower and a low level of diversification of materials used. This study aimed to determine the applicability of various materials for wet process, mechanized construction and eco-friendly building materials through a comparison with dry premixed mortar. As a result, it was found that resin plaster and gypsum plaster's strength is lower than that of dry cement mortar, but their mechanization application, construction simplification, smoothness and bond strength are higher than that of dry cement mortar. And estimate that is valid as workability, bonding strength, eco-friendly building material in occasion of gypsum plaster.