• 한국미생물·생명공학회지
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• 제18권1호
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• pp.31-34
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• 1990

중온성과 고온성인 황산염 환원세균들을 사용하여 dibenzothiophene, 원유 및 Bunker C 유의 탈황실험을 하여 중온성인 분리균주 Desulfovibrio desulfuricans M6는 dibenzothiophene, crude oil를 42, 17 까지 탈황시켰으며, 고온성은 Desulfovibrio thermophilus에서 dibenzothiphene Bunker C 유를 각각 68, 33 탈화시켜, 황산염 환원세균에 의한 석유의 탈황 가능성을 보였다. 또한 Desulfovibrio 속과 Desulfotomaculum 속의 탈황 능력의 차이로부터 탈황기작이 hydrogenase와 환원력 원인 수소가 관련이 있다는 것을 알았다.

• Advances in environmental research
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• 제9권3호
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• pp.215-232
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• 2020

Crude oils are essential source of energy. It is majorly found in geographical locations beneath the earth's surface and crude oil is the main factor for the economic developments in the world. Natural crude oil contains unrefined petroleum composed of hydrocarbons of various molecular weights and it contains other organic materials like aromatic compounds, sulphur compounds, and many other organic compounds. These hydrocarbons are rapidly getting degraded by biosurfactant producing microorganisms. The present study deals with the isolation, purification, and characterization of biosurfactant producing microorganism from oil-contaminated soil. The ability of the microorganism producing biosurfactant was investigated by well diffusion method, drop collapse test, emulsification test, oil displacement activity, and blue agar plate method. The isolate obtained from the oil contaminated soil was identified as Bacillus subtilis. The identification was done by microscopic examinations and further characterization was done by Biochemical tests and 16SrRNA gene sequencing. Purification of the biosurfactant was performed by simple liquid-liquid extraction, and characterization of extracted biosurfactants was done using Fourier transform infrared spectroscopy (FTIR). The degradation of crude oil upon treatment with the partially purified biosurfactant was analyzed by FTIR spectroscopy and Gas-chromatography mass spectroscopy (GC-MS).

• Journal of Biosystems Engineering
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• 제35권3호
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• pp.158-162
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• 2010

The effect of fuel injection characteristics on engine performance has been known for improving fuel economy and emission reduction. In this study, the spray characteristics of crude palm oil blended fuel with conventional diesel fuel was investigated. The experiments were performed to evaluate the effect of crude palm oil blending ratio and injection pressure on the spray behavior. The droplet size of injected fuel was analyzed through laser diffraction particle analyzer (LDPA). Also, spray atomization characteristics were investigated in terms of Sauter mean diameter (SMD) and droplet distribution at various injection conditions. Fuel containing crude palm oil has different spray pattern on account of the high viscosity. Through those experimental results, we found that the increase of blending ratio made droplet size larger, SMD of biodiesel 100% was increased 30.2% than that of diesel fuel 100% under injection pressure of 60 MPa.

• 한국미생물·생명공학회지
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• 제27권6호
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• pp.452-457
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• 1999

Several bacterial strains utilizing crude oil as their sole carbon and energy sources were isolated from marine. One of the strains named KCL-1 showed the highest degradative activity for crude oil and the best growth rate. This strain was identified as a Klebsiella sp. based on the morphological, biochemical, and physiological characteristics. The optimum cultural conditions were as follows; $32^{\circ}C$~$37^{\circ}C$ for temperature and 7.0 for initial pH. Additionally, the optimal concentration of sodium chloride was 3.0%, indicating that this strain was derived from seawater. KCL-1 could use several kinds of n-alkane hydrocarbons from octadecane to hexacosane as a sole carbon source. The degradation of crude oil by KCL-1 was stimulated by addition of octadecane in the culture. The emulsifying activity by KCL-1 was highest after 3 days of cultivation under the condition of 3.0% sodium chloride, pH 7.0 and $37^{\circ}C$.

• 통상정보연구
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• 제10권3호
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• pp.459-474
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• 2008

Under violent competition to secure international raw materials, safe supply and demand of crude oil that only relies on import among main raw materials is an important task for Korean economic development. Therefore, this study aims to analyze the impact of price change of international crude oil on merchandise balance. It also presents political suggestions in preparation for national economic development and safety and develops an organized and long-term overseas resources development program. As the time-series data which had the 1st difference contribute to dismissal of the null hypothesis successfully, we carry out a multivariate cointegration test developed by Johansen (1988) and find that at least one cointegration vector exists. And, when Impulse Response Function is introduced, as the crude oil import price shows a negative impact from Step 2, then an extreme change, a positive impact since Step 13, is maintained and a safe result appears.

• KSBB Journal
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• 제10권5호
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• pp.582-588
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• 1995

해양의 유류유출이 잦은 지역으로부터 crude oil 분해능이 뛰어난 미생물을 분리하여 통정한 결과 Pseudomoans 속으로 판명되였으며, 이를 Pseud$\sigma$ moans sp. CHCS-2로 명 명하였다. 이 균주가 배양 중에 생산하는 biosurf actant의 생생 최적 pH 및 NaCI 농도는 각각 8.0 및 3.0% 였으며, 질소원인 peptone에 영향을 받았다. 2% Kuwait crude oil이 첨가된 배양액을 48, 96, 132시간별로 gas chroma­t tography를 이용, 잔류 oil을 분석한 결과 Kuwait crude oil의 C10-CI4부위에 biosurf actant가 작용하여 분해하였으며, 배양 상층액으로부터 Amberlite XAD-7을 이용한 흡착 chromatography와 Sepha­d dex G-100을 이용한 gel chromatography, 그리고 HPLC를 이용하여 biosurf actant를 분리. 정제한 결과 유화력이 뛰어난 단일 peak를 얻었다. Bio-sur­f f actant 유화력은 $40^{\circ}C$에서 가장 좋았으며, 안정성 은 $30^{\circ}C$에서 $60^{\circ}C$까지의 넓은 온도 범위에서 유지 되었다. 또한, 정제된 biosurf actant를 이용하여 계 연장력에 미치는 영향을 검토한 결과, 상엽적으로 널리 판매되고 있는 Tween 80, Tween 60 그리고 SDS보다 표연장력 저하능력이 뛰어난 것으로 밝혀졌다.

• 전자공학회논문지
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• 제54권1호
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• pp.152-156
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• 2017

지금까지의 초음파센서와 관련된 연구 중 대부분은 대기 중에서 사용하거나 수중에서 사용하는 연구가 대부분이었다. 본 연구는 원유나 석유 등의 유종에서 사용하는 경우에 관한 것으로 초음파 소자에 고전압을 인가해야 하는 초음파의 특성 상 폭발의 위험이 있어 폭발에 대한 우려 없이 유종에서 초음파를 효과적으로 발생시키기 위한 초전도 셀의 특성에 대해 연구하였다. 본 연구를 통해 폭발의 위험이 없으면서 원유 등 유종에서 초음파를 투과하여 원유의 깊이를 측정하거나 원유 바닦의 슬러지를 측정할 수 있는 가장 적합한 초전도셀의 면적, 두께, 발사 주파수 등을 도출하였으며 초음파센서에 24V의 전압을 인가하여 200kHz 주파수를 발생시킬 경우, 초전도셀의 최적 직경은 26~28mm, 두께는 9mm로 하는 것이 최적임을 확인하였다.

• Corrosion Science and Technology
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• 제19권2호
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• pp.66-74
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• 2020

In this paper, the author's team has carried out a comparative experimental study on the corrosion characteristics of Q235 steel commonly used in large-scale storage tanks under the specific bottom water environment found with Russian and Daqing crude oil. It was found that there is a certain degree of uniform or local corrosion on the tank floor depending on the kind of bottom water. The bottom water corrosion of Daqing crude oil is a uniform corrosion caused by carbon dioxide. While the Russian crude oil bottom water corrosion is clearly local corrosion caused by co-corrosion of carbon dioxide and hydrogen sulfide, here the corrosion rate is obviously higher than that caused by Daqing crude oil. There are two modes of storage tank inspection and maintenance that have been currently adopted by Chinese refining and chemical enterprises: a regular inspection mode and a API581-2016 risk-based detection mode. These modes have been effectively combined to form an intelligent tank inspection and maintenance mode, software tools to support this intelligent inspection and maintenance management have been developed.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.995-1000
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• 2011

The bioremediation potential of crude oil by Polyporus sp. S133 pre-grown in wood meal was investigated in two separate experiment trials; liquid medium and soil. The effect of three nutrients (glucose, polypeptone, and wood meal), oxygen flow, and some absorbent on the efficiency of the process was also evaluated. Degradation of crude oil in soil was significantly increased with an addition of oxygen flow and some absorbent (kapok and pulp). The highest degradation rate of crude oil was 93% in the soil with an addition of 10% kapok. The present study clearly demonstrates that, if suitably developed, Polyporus sp. S133 could be used to remediate soil contaminated with crude oil.

• 수산경영론집
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• 제32권1호
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• pp.15-39
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• 2001

The study, using the input-output analysis of 402 industrial sectors by Bank of Korea(BOK) and the resulting outcomes of price model, aims to evaluate the spillover effects the international fluctuations in crude oil prices have on the commodities prices and consequently, analyse the management and profitability of the offshore fisheries in Korea. At present, the fisher men are provided with tax-free oils for their fishing operations as specified under the Special Tax Treatment Control Law. However, the exhaustion of marine resources and new international fisheries agreements, which resulted in the loss of fishing grounds, made the stable catch even more unpredictable and the hike in the price of the international crude oil would have adverse effects on the fishing industry. The study revealed that the increasing rise in the price of crude oil would exert sweeping spillover effects on other industry sectors in general and accordingly, lead to a poorer performance by fisheries. The price spillover coefficients for the diesel oil was 0.6026, which would translate into the 42.6% increase in the prices of oil when the increase ratio of 73.3% for the base crude oil was applied based on the calculation methods employed in the study. This in turn increased the ratio of diesel oil required in the offshore fisheries from 23.3% to 16.6%, diminishing the ratio of current net profits to minus 2.0% from 4.2% otherwise. By fishing type, the Pair Trawl suffered current net profits loss most by ratio of minus 9.4% and other fisheries such as Coastal Stow Nets, Coastal Angling, Danish Sein also suffered ratio of 7% and more in the loss of current net profits. With the deteriorating fishing performance, coupled with the increasing international crude oil prices, it is urgently required that the authorities concerned deliberate in depth on such schemes as follows in efforts to secure stable fishing production. First, provision of large-scale storage facilities for oil is needed to timely adapt to the fluctuations in international crude oil prices. Secondly, in line with the stabilization of tax-free oil prices, duty levied on oils for fishing and tax collected from the refineries need to be tax-exempt. Thirdly, the beneficiaries from the provision of tax-free oil should be broadened, not limited to special fishing operation only. Fourth, investment in stabilization of the oil prices should be encouraged, possibly through funding from the formation of fisheries development funds underway.