• The Korean Journal of Petroleum Geology
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• v.7 no.1_2 s.8
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• pp.35-40
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• 1999

Chemical and isotopic compositions of hydrocarbon gases were analyBed to characterize the properties of the shallow gases distributed in the southeastern part of the Ulleung Basin, offshore Korea. Sediments from the core were also analyzed to determine the characteristics and relationship to shallow gases. Hydrocarbon gases in the sediments consisted of methane (697.9-6054.4 ppm), ethane, propane, butane and hexane. The total carbon content of the sediments ranges from 1.84fe to $5.11{\%}$ and the total organic carbon content ranges from $0.29{\%} \;to\; 2.65{\%}$. High C/N ratio (>10) indicates that input of terrestrial organic matter was prevalent at the time of deposition. The methane content and stable isotopic data indicate that hydrocarbon gases from the sediments are identified to be thermogenic gas and mixture of both biogenic and thermal gases. Based on the Rock-Eval and carbon isotopic data, the level of thermal maturity of organic matter in the sediments $(Tmax<425^{\circ}C)$ is lower than that of gas. It suggests that thermal gases in the sediments migrated from the deeper sediments than the penetrated depth.

• Fire Science and Engineering
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• v.15 no.1
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• pp.16-22
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• 2001

Thermal properties of PP and LLDPE dusts from chemical plant and their risks of coexisting with oxidizer were investigated by a pressure vessel. The thermal decomposition of PP and LLDPE dusts with temperature using DSC and the weight loss with temperature using TGA were also investigated to find the thermal hazard of PP and LLDPE dusts. Using the pressure vessel which can estimate ignition and explosion of PP and LLDPE dusts coexisting with oxidizer, a series of bursting of a rupture disc, experiments has been conducted by varying the orifice diameters the weight ratio of the sample coexisting with oxidizers and the species of oxidizer. And fire gases was measured by gas analyser ($ECOM-A^+$). According to the results of the thermal analysis of PP and LLDPE dusts, the decomposition temperature range of PP and LLDPE dusts was 200 to 350 and 300 to $500^{\circ}c$, respectively. The risk of PP and LLDPE dusts coexisting with oxidizer was increased as the orifice diameter was decreased. On the other hand, it was increased as the weight ratio of the sample to the oxidizer were increased. In addition, the risk of PP and LLDPE dusts coexisting with oxidizer was affected by the decomposition temperature of the sample and oxidizer. It is found that the risk of fire becomes high when the decomposition temperature of the sample is about same as that of oxidizer. Also, the fire gases was occurred carbon monoxide and carbon dioxide. The amount of carbon monoxide generated was found to be much higher in PP decomposition than in LLDPE due to incomplete combustion of PP which has high content of carbon in chemical compound.

• Geophysics and Geophysical Exploration
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• v.19 no.1
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• pp.37-44
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• 2016

$CO_2$-EOR (Carbon Dioxide-Enhanced Oil Recovery), one of the enhanced oil recovery methods, helps to not only enhance the production of oil, but also store carbon dioxide in underground. However, if micro fractures occur when during the injection of $CO_2$, it is difficult to make permanent storage of $CO_2$ in reservoir and can cause contamination of groundwater and soil. Therefore, in this study, we performed microseismic monitoring to investigate the occurrence of fractures during the $CO_2$ injection at the Meruap oil reservoir, Indonesia. To pick the first arrivals of microseismic events, Improved MER (Modified Energy Ratio) method was used. After picking the first arrivals, hodogram analysis was carried out by using the data recorded at three component geophones to calculate the back azimuth of events. Finally, locations of microseismic events were decided by using the results of first arrival picking and hodogram analysis. Estimated locations showed that all microseismic events were occurred at surface and any fracture did not occur around the reservoir. Moreover, by analyzing noise characteristic, we confirmed that almost of picked first arrivals were due to the repetitive mechanical noise.

• Analytical Science and Technology
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• v.8 no.2
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• pp.131-138
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• 1995

We have discussed on the structural transition and its effect on the electrical property of Li-GFDICs and Li-PCDICs occuring during the deintercalation process of Li-Graphite Fiber Intercalation Compounds(Li-GFICs) and Li-Petroleum Cokes Intercalation Compounds(Li-PCDICs) synthesized under pressure and temperature by spontaneous oxidation by air circulation. The analytical results were obtained by X-ray diffraction and electrical specific resistivity measurements. According to X-ray analysis, we have found that the major stage of Li-GFICs was stage 2 and those of Li-PCICs were stage 1 and stage 2, respectively. And from this results of the deintercalation process, we have found that the deintercalation process did not occur any more after 5th week of Li-GFDICs and after 3rd week of Li-PCDICs. According to the results of the electrical specific resistivity measurements, Li-GFDICs showed little variation to 3rd week and rising in the steady curve after 4th week, while Li-PCDICs showed a rising in the steady curve to 3rd week and a declining curve after 3rd week. Therefore from these results, we can consider that graphite fiber and petroleum cokes as a substrate can be also used as an anode material of battery because they have good intercalation-deintercalation reactivity with lithium.

• 한국석유지질학회:학술대회논문집
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• 2005.09a
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• pp.94-100
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• 2005

동해 울릉분지 북서부해역에서 채취한 코어퇴적물을 이용하여 울릉분지의 제4기 후기 층서와 퇴적환경을 연구하였다. 이를 위하여 테프라층서, 탄소연대측정, 퇴적상, 퇴적물의 암질, 퇴적물과 공극수의 원소성분 등을 분석하였다. 퇴적상을 기준으로 코어퇴적물은 Unit 1, Unit II 및 Unit III으로 나누어지며, Unit의 경계부근에서는 주로 화산력으로 구성된 2매의 향암질 또는 조면암질 테프라층과 주로 화산재로 구성된 1매의 유문암질 테프라층이 협재되어 나타난다. 이들 테프라층에는 울릉도에서 기원한 울릉-오키층(Unit I/II 경계, 약 8.1 cal. kyr BC)과 울릉-야마토층(약 30.7 cal. kyr BC), 일본에서 기원한 아이라-탄자와층(Unit I/II경계, 약 22.8 cal. kyr BC)이 있다. Unit II의 중간부근에서 발견되는 DLM(Dark Laminated Mud) 층에는 망간보다는 철이 상대적으로 풍부하고, 철은 주로 구상집적체의 황화철로 발견되는데, 이들 광물은 정체환경 동안 물의 순환이 약화된 시기에 무산소환경에서 형성되었다. 퇴적물 내 유기물은 해양성 기원으로, 열적 성숙단계가 대부분 미성숙단계에 놓여 있다. Termination I 전에 급격하게 총유기탄소 (TOC)의 함량이 증가함을 보여주는데, 이는 빙기에서 간빙기로 변하는 시기에 해수면 변동과 관련이 있는 것으로 보인다. 공극수와 공기층 가스의 분석에 의하면, 황산염($SO_4^{2-}$) 농도는 매몰심도와 함께 증가하고, 반대로 공기층 가스의 주성분인 메탄($CH_4$)의 농도는 감소한다. 이는 미생물학적인 활동과 관련된 황산염 환원작용이 코어 상부에서 일어났으며, 점차 메탄생성단계 (methanogenesis)로 전이가 일어났음을 의미한다.측해본 결과 침몰선체의 강도는 초기강도에 비해 약 2/5정도 감소하였음을 알 수 있었다.할 수 있었다. 이 연구 사례를 통하여 3차원 GPR 탐사 또한 국부적인 이상대의 규명뿐만 아니라 광역적인 고고학 조사에도 다른 물리탐사와 마찬가지로 쉽게 활용될 수 있다는 결론을 얻을 수 있었다. 3차원 GPR 탐사가 향후 국내의 문화재 조사에 표준화된 탐사과정 중의 하나로써 적극 활용되길 기대한다.larity가 높은 oil에서는 약 $70 {\~} 90\%$의 phenoxyethanol이 유상에 존재하였다. 또한, 미생물에 대한 항균력도 phenoxyethanol이 수상에 많이 존재할수록 증가하는 경향을 나타내었다. 따라서, 제형 내 oil tomposition을 변화시킴으로써 phenoxyethanol의 사용량을 줄일 수 있을 뿐만 아니라, 피부 투과를 감소시켜 보다 피부 자극이 적은 저자극 방부시스템 개발이 가능하리라 보여 진다. 첨가하여 제조한 curd yoghurt는 저장성과 관능적인 면에서 우수한 상품적 가치가 인정되는 새로운 기능성 신제품의 개발에 기여할 수 있을 것으로 사료되었다. 여자의 경우 0.8이상이 되어서 심혈관계 질환의 위험 범위에 속하는 수준이었다. 삼두근의 두겹 두께는 남녀 각각 $20.2\pm8.58cm,\;22.2\pm4.40mm$으로 남녀간에 유의한 차이는 없었다. 조사대상자의 식습관 상태는 전체 대상자의 $84.4\%$가 대부분이 하루 세끼 식사를 규칙적으로 하고 있었으며 식사속도는 허겁지겁 빨리 섭취하는 경우가 남자는 $31.0\%$, 여자는 $21.4\%$로 나타났고 이들을 제외한 나머지 사람들은 보통 속도 혹은 충분한 시간을 가지고 식사를 하였다. 평소 식사량은 조금 적게

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.75-82
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• 2016

The technology of fast pyrolysis is regarded as a promising route to convert lignocellulose biomass into bio-oil which can be upgraded to transportable fuels and high quality chemical products. Despite these promises, commercialization of bio-oil for fuels and chemicals production is limited due to its notoriously undesirable characteristics, such as high and changing viscosity, high water and oxygen contents, low heating value and high acidity. Therefore, in this study quality improvement of bio-oil through vaccum distillation had been targeted. A 600 g of cork oak(Quercus variabilis) which grounded 0.8~1.4 mm was processed into bio-oil via fast pyrolysis for 1.64 seconds at $465^{\circ}C$ and temperature of vaccum distillation(100hPa) was designed to control, $40^{\circ}C$, 50, 60, 70, and 80 for 30min. Bio-oil, biochar, and gas of pyrolytic product were produced to 62.6, 18.0 and 19.3 wt%, respectively. The water content, viscosity, HHV(Higher Heating Value) and pH of bio-oil were measured to 0.9~26.1 wt%, 4.2~11.0 cSt 3,893~5,230 kcal/kg and 2.6~3.0, respectively. Despite these quality improvement, production was still limited due to its notoriously undesirable characteristics, therefore continous quality improvement will be needed in order to use practical fuel of bio-oil.

• The Korean Journal of Petroleum Geology
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• v.2 no.2 s.3
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• pp.91-99
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• 1994

In the Heunghae area, genetic relationships among sedimentary facies, lithology, stratigraphy and diagenetic mineral facies of the Yeonil Group, are discussed. Conglomerate and sandstone of lower to middle parts of the Yeonil Group contain considerable amounts of volcaniclastic sediments, which were derived from the Tertiary volcanics exposed in the western margins of the sedimentary basin. A new stratigraphic division of the Yeonil Group into the Chunbuk and Pohang Formations is proposed on the basis of sedimentary facies, lithologic characteristics including volcaniclastic feature, and the presence of a key bed of siliceous mudstone overlying the Chunbuk Formation. Diagenetic mineral facies largely depend on the lithology and composition of sediments. Heulandite, smectite, calcite, and opal-CT are commonly found as diagenetic minerals in the Yeonil Group. Among these authigenic minerals, heulandite occurs as the coarse- grained main cement in conglomerates and sandstones of the Chunbuk Formation. Formation of the zeolite cement is favored by partial volcaniclastic lithology of the Chunbuk Formation. Smectite composition and diagenetic mineral facies such as heulandite and opal-CT may reflect that the Yeoil Group has undergone a shallow rial temperature ranging $40{\~}60^{\circ}C$.

• The Korean Journal of Petroleum Geology
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• v.10 no.1_2 s.11
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• pp.18-22
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• 2004

To identify and interpret the distribution and the characteristics of the gas hydrate layers in the Ulleung Basin, we have surveyed and gathered the multi-channel seismic data, Chirp sub-bottom profiler, SeaBeam and 12 m piston core samples since 1996. In previous works, high-resolution seismic profiles showed acoustic anomalies such as acoustic void, acoustic turbidity and pock mark which indicate the presence of gas-charged sediments. The patterns of horizontal degassing cracks originated from free methane expansion is the strong indicator of shallow gas-charged sediments in the core samples. The observation of submarine slides and slumps from destabilizing the sediments in the southern part of the Ulleung Basin may also point out that the gas had been released from gas hydrate dissociation during lowstand of sea level. The multi-channel seismic data show BSR, blanking and phase reversal. The gas hydrate layers above which large-scale shallow gases are distributed exist at the depth of about 200 m from the sea-floor with water depth of 2,100 m. From the interpretation of seismic sections in the southern Ulleung Basin, gas hydrate layers occur in the Pleistocene-Holocene sediments. These gas-charged sediments, acoustic anomalies and BSR may be all related to the existence of gas hydrate layers in the study area.

• Fire Science and Engineering
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• v.26 no.6
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• pp.7-14
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• 2012

This paper is to develop analytical techniques of flammable liquids which have been used for accelerating fire in accidental fires and arsons. We tested the temperature distribution of ceiling, fire patterns on the floor, and existence of flammable liquids and a check with GC/MS about flammable liquids comparing with papers, newspapers, and clothing. Research findings are as follows. The temperature of ceiling is influenced by flame. So gasoline and thinner was observed that combustible materials would be burned by flame. The fire patten on the floor was observed that flammable liquids had specialized pattern comparing combustible materials. When combustible materials on the PVC (Polyvinyl chloride) floor was burned, they didn't react to the gas detector. But flammable liquids had opposite results. After 7 days, we identified components of fire residues with the GC/MS (Gas Chromatography/Mass Spectrometry) about existence of flammable liquids and got components of flammable liquids. Fire investigation is a complicated processes. But we understand characteristics of materials, need detail investigations, and use the GC/MS to analyse flammable materials.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.250.2-250.2
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• 2010

빛과 공기 중의 이산화탄소를 고정화하여 생성되는 바이오매스(biomass)로부터 다양한 에너지 및 물질을 생산하는 연구는 석유고갈과 환경문제 해결의 한 방안으로서 활발히 진행되어 왔으며, 앞으로도 그 지속 가능성과 환경 친화성에 의해 바이오에너지 이용 및 보급은 꾸준한 증가세를 보일 것으로 전망된다. 바이오디젤, 바이오에탄올의 경우는 미국, 브라질, EU, 한국 등에서 상용화되어 사용되고 있으며 그 생산량이 계속적으로 증가하고 있다. 하지만, 바이오연료의 보급 증가는 식량 자원과의 충돌과 열대우림 파괴 등의 부작용을 일으키고 있다. 이러한 문제 해결의 일환으로 단위면적당 생산성이 대두, 유채보다 월등한 것으로 보고되는 미세조류에 대한 관심이 증가하고 있으며 우수 미세조류종 개발, 미세조류 고속배양 및 수확, 미세조류로부터 에너지 및 유용물질, 소재 생산에 대한 연구가 활발히 진행되고 있다. 본 연구에서는 미세조류로부터 바이오디젤 원료유를 생산하기 위해 Soxhlet을 이용한 추출 방법을 이용하였다. 추출되는 오일은 사용 용매의 극성에 따라 물성과 추출 효율에 차이가 큰 것으로 나타났다. 강한 극성의 용매일 경우, 엽록소와 단백질이 같이 추출되는 문제가 있으며 약한 극성 용매는 세포벽의 방해로 용매가 세포내부로 흡수되지 못하는 문제가 있다. 추출 효율이 높은 극성용매의 경우 불순물을 제거해야 고순도의 바이오디젤의 생산이 가능하고 비극성 용매는 추출 오일의 물성은 좋으나 수율이 매우 낮게 측정되었다. 이러한 동시추출을 방지함과 동시에 추출 효율을 높이기 위해 본 연구에서는 세포벽 파괴 후 용매추출하는 방법으로서 미세조류를 Microwave에 노출시켜 오일 추출율을 증가시키는 전처리 연구를 수행하였다. 전처리시, Microwave에 의한 열 발생은 미세조류를 탄화시키기 때문에 열매체로서 물을 혼합하여 탄화를 방지하고 세포벽 내외부의 가열효과로 세포벽을 파괴하고자 하였다. Microwave에 의한 에너지 손실을 줄이며 세포벽 파괴에 효과적인 수분혼합비를 조사하였으며 Microwave에 노출 후 잔류수분을 건조하고 효율적으로 용매를 접촉시키기 위해 분쇄를 수행하였다. 모든 전처리 반응을 거친 미세조류에서 약 2배 증가된 추출수율을 얻을 수 있었으며, SEM을 통해 전처리 미세조류와 미전처리 미세조류를 분석해본 결과 전처리 미세조류의 다공성이 증가함을 확인하였다. 또한, 90%의 메탄올에 미세조류를 녹여 엽록소 함유량을 측정한 결과, 전처리 미세조류의 엽록소가 미전처리 미세조류보다 약 7배가량 감소함을 확인할 수 있었다.