• 한국화재소방학회논문지
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• 제28권2호
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• pp.54-63
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• 2014

본 논문은 CO센서의 화재에 대한 감지특성을 분석 후 화재감지기로서의 적용성 판단을 하기 위한 논문이다. CO센서의 화재감지기로의 적용성을 판단하기 위해 UL 268에서 규정하고 있는 화재시험실과 유사한 규모의 화재실험장을 설계 제작하고, UL 268에서 제시된 화재시험기준에 준한 실화재실험을 실시하여 화원 종류에 따른 CO센서와 광전식연기감지기의 다양한 화원의 화재에서 발생하는 일산화탄소와 연기에 대한 감지특성을 측정하여 비교 분석하였다. 실험결과 종이화원 및 목재화원과 같이 불완전연소로 진행되는 초기화재에서 CO센서가 광전식연기감지기보다 약 2~3배 빠른 감지특성이 나타났다. 특히, 목재훈소화재에서 CO센서의 감지특성이 매우 우수한 것으로 나타났다.

• 한국환경성돌연변이발암원학회지
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• 제24권4호
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• pp.163-170
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• 2004

CYP1B1 enzyme metabolize PAHs and estradiol. CYP1B1 metabolize estradiol to 4-hydroxyestradiol that is considered as carcinogenic metabolite. Luciferase activity was induced about 20 folds over that control by 1 nM TCDD (2,3,7,8-tetrchlorodibenzo-p-dioxin) and these inductions were dose-dependent. Recent industrialized society, human hasbeen widely been exposed to widespread environmental contaminants such as PAHs (polycyclic aromatic hydrocarbon) that are originated from the incomplete combustion of hydrocarbons. PAHs are known to be ligands of the AhR (aryl hydrocarbon receptor). Induction of cytochrome P4501B1(CYP1B1) in cell culture is widely used as a biomarket for PAHs. Therefore we have studied the effect of PAHs in the human breast cancer cells MCF-7 to evaluate bioactivity of PAHs. Cytochrome P4501B1(CYP1B1) is known to be inducible by xenobiotic compounda such as policyclic aromatic hydrocarbon (PAH) and dioxins such as 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). And these induction of CYP1B1 is also regulated by many categories of chemicals. In order to investigate the effects of several chemicals on CYP1B1 gene expression in luciferase gene, and then transfected into these cells. After treatment of chemicals, the luciferase activity was measured. We examined effects of PAHs on the CYP1B1-lucifrease reporter gene and CYP1B1 mRNA level. Benzo(k)fluoranthene showed strong response to CYP1B1 promoter activity stimulation, and also CYP1B1 mRNAs increase in MCF-7 cells in a concentration-dependent manner. flvonoids such as genistein decreased B(k)F induced luciferase activity at low concentration. it exhibited stimulatory effect at high concentration.

• 한국의사학회지
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• 제18권1호
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• pp.3-14
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• 2005

Among modern people's life-style, the lack of exercise and sleep is related to infertility. Underexercise accumulates damp-sputum, resulting in the insufficiency of essence. It also obstructs the creation of essence, leading to insufficient essence. Activities at night without sleep cannot create the condition to help the process of yin, causing the insufficiency of essence. Fast food is made from the cattle which are fed the feed containing growth hormone and antibiotics in large quantities. Growth hormone causes the process of yang excessively in human body, while antibiotic suppresses the process of yin, leading to excessive damp-heat and hyperactive ministerial fire. Antiseptic included in instant food hampers the process of fermentation, or yin, and inhibits the digestion mechanism, obstructing damp-heat and bringing about hyperactive ministerial fire. Intake of excessive flesh and meat gives rise to incomplete combustion and hinders the creation of essence, causing hyperactive ministerial fire due to the lack of yin. Milk suits the calf that has a rapid growth cycle. Milk intake by humans leads to the rapid process of yang and eventually hyperactivity of ministerial fire. The imbalance between yin and yang, with essence insufficent and ministerial fire hyperactive, causes infertility in three aspects. First, the lack of essence itself makes conception difficult. Secondly, damp-sputum resulting from ministerial fire obstructs the circulation of qi and blood. It also hampers the normal supply of qi and blood to the uterus. Thirdly, the excessive process of yang may result in infertility. Generally speaking, pregnancy starts with implantation. If the excessive process of yang is in progress in body, static condition needed for implantation cannot be maintained, leading to infertility.

• 한국화재소방학회논문지
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• 제32권3호
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• pp.8-13
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• 2018

여러 산업분야나 일상생활에서 다양하게 쓰이고 있는 플라스틱의 중요성과 효용성에 비해 화재 위험성에 관한 연구가 매우 부족하여 본 연구에서는 5종의 플라스틱 제품의 화재 위험성을 콘칼로리미터(ISO 5660-1)로 측정하였다. 그 결과, PVC판의 착화시간(TTI)은 196 s로 다른 플라스틱보다 연소시간이 가장 지연되었고, PS판은 19 s로 착화시간이 가장 짧았다. PS판의 총열방출열량(THR)은 가장 낮게 측정된 PVC판 보다 213.07% 높게 측정되었다. 또한 PS판의 CO는 다른 플라스틱에 비해 1.45~4.21배, $CO_2$는 1.77~6.97배 더 높게 나타나 불완전연소가 가장 높고 인명피해가 가장 많이 발생할 것으로 예측된다. 따라서 화재 위험성은 PS판이 가장 위험하고, PVC판이 가장 안전한 것으로 나타났다.

• 공업화학
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• 제22권2호
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• pp.155-160
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• 2011

동물성유지는 식물성유지에 비해 산화안정성이 뛰어나며, 높은 발열량과 세탄가를 보여 불완전 연소율이 낮다는 장점을 가지고 있으나 포화지방산의 함량이 높고, 원료유지에 불순물 함량이 높아 정제과정이 필요하다는 단점을 가지고 있다. 본 연구에서는 동물성 유지로 폐돈지를 선정하여 초음파에너지를 이용한 전이에스테르화반응의 최적조건을 설정하고자 하였다. 또한 기존공정의 가열 및 교반을 대체할 수 있는 초음파에너지 효과를 확인함으로써 새로운 바이오디젤 제조공정을 제시하고자 하였다. 기존가열방식을 이용한 폐돈지의 전이에스테르화 반응은 $55^{\circ}C$에서 메탄올과 돈지의 반응몰비 12에서 1 h 반응한 경우 가장 우수한 전환특성을 나타내었다. 전이에스테르화 반응에 초음파에너지를 조사할 경우 최적 초음파 조사세기 500 W에서 반응시간을 30 min으로 크게 단축할 수 있었다. 또한 제조된 바이오디젤의 성능평가 결과 점도는 $0{\sim}70^{\circ}C$ 범위에서 1.3~4.0 cP, 발열량은 40.3 MJ/kg으로 바이오디젤 성능기준을 만족하였다.

• Tribology and Lubricants
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• 제36권6호
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• pp.385-390
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• 2020

It rains heavily, such as long rain and typhoons, during a typical rainy season in Korea. In this season, several fuel contamination accidents by water and vehicular problems caused by water contaminated fuel occur. Many research groups have studied the effects of water contaminated fuel on vehicles and environment. However the characteristics of water contaminated fuel have not been studied. In this study, we prepared diesel samples with a constant ratio of water (0~30 volume %) using an emulsifier. Then, we analyzed these diesel samples for their representative fuel properties. In the analytical results, diesel with 30% water showed an increase in fuel properties such as density (823→883 kg/㎥), kinematic viscosity (2.601→6.345 ㎟/s), flash point (47→56℃), pour point (-22→2℃), CFPP (cold filter plugging point) (-17→20℃) and copper corrosion number (1a→2a). The low temperature characteristics, such as low pour point and CFPP, blocks the fuel filter in the cold season. In addition, water contaminated diesel decreases lubricity (190→410 ㎛) under high frequency reciprocating rig (HFRR) and derived cetane number (54.81→34.25). The low lubricity of fuel causes vehicle problem such as pump and injector damage owing to severe friction. In addition, the low cetane diesel fuel increases exhaust gases such as NOx and particulate matters (PM) owing to incomplete combustion. This study can be used to identify the problems caused by water contamination to vehicle and fuel facilities.

• 한국가스학회지
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• 제27권1호
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• pp.1-12
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• 2023

석탄가스화는 석탄을 불완전 연소하여 수소와 일산화탄소로 이루어진 합성가스를 생성하는 공정이다. 기 존 석탄 연소와 달리 질소 산화물이나 황 산화물이 배출되지 않고 미세먼지 발생량이 적어 석탄을 청정하게 이용할 수 있으며 합성가스를 통해 부가적인 화학물질을 생산할 수 있다. 석탄가스화는 합성가스 생산방식에 따라 석탄가스화복합화력발전(Integrated Gasification Combined Cycle, IGCC), 플라즈마 석탄가스화, 지하석탄 가스화(Underground Coal Gasification, UCG)로 분류된다. 최근에는 합성가스의 수소를 활용하기 위하여 일산화탄소를 수소로 전환하는 수성가스전환(Water Gas Shift, WGS) 반응기와 이산화탄소를 포집하는 설비를 결합하는 사례가 늘고 있다. 본 연구에서는 석탄가스화와 합성가스를 이용한 수소 생산 방법에 대하여 정리하였으며 현재 진행되고 있는 석탄가스화를 이용한 수소 생산 프로젝트를 조사하였다.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2019년도 정기학술대회 발표논문집
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• pp.134-134
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• 2019

Utilization of organic waste as a renewable energy source is promising for sustainability and mitigation of climate change. Pyrolysis converts organic waste to gas, oil, and biochar by incomplete biomass combustion. Biochar is widely used as a soil conditioner and adsorbent. Biochar adsorbs/desorbs metals and ions depending on the soil environment and condition to act as a nutrient buffer in soils. Biochar is also regarded as a carbon storage by fixation of organic carbon. Phosphorus (P) and nitrogen (N) are strictly controlled in many wastewater treatment plants because it causes eutrophication in water bodies. P and N is removed by biological and chemical methods in wastewater treatment plants and transferred to sludge for disposal. On the other hand, P is an irreplaceable essential element for all living organisms and its resource (phosphate rock) is estimated about 100 years of economical mining. Therefore, P and N recovery from waste and wastewater is a critical issue for sustainable human society. For the purpose, intensive researches have been carried out to remove and recover P and N from waste and wastewater. Previous studies have shown that biochars can adsorb and desorbed phosphates implying that biochars could be a complementary fertilizer. However, most of the conventional biochar have limited capacity to adsorb phosphates and nitrate. Recent studies have focused on biochar impregnated with metal salts to improve phosphates and nitrate adsorption by synthesizing biochars with novel structures and surface properties. Metal salts and metal oxides have been used for the surface modification of biochars. If P removal is the only concern, P adsorption kinetics and capacity are the only important factors. If both of P and N removal and the application of recovery are concerned, however, P and N desorption characteristics and bioavailability are also critical factors to be considered. Most of the researches on impregnated biochars have focused on P removal efficiency and kinetics. In this study, coffee waste is thermally treated to produce biochar and it was impregnated with Mg/Al to enhance phosphates and nitrate adsorption/desorption and P bioavailability to increase its value as a fertilizer. Kinetics of phosphates and nitrate adsorption/desorption and bioavailability analysis were carried out to estimate its potential as a P and N removal adsorbent in wasewater and a fertilizer in soil.

• 보존과학회지
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• 제35권5호
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• pp.470-479
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• 2019

본고에서는 백제금동대향로의 고화질 촬영 및 실측을 통해 배연공과 흡기공의 확장이유를 밝히고자 하였다. 실험을 위해 백제금동대향로를 3차원 정밀 스캔한 뒤 스캔한 원본데이터를 기반으로 백제금동대향로 정밀재현품과 시판복제품을 3차원 스캔하여 전체적인 형태와 세부적인 문양을 원본데이터와 비교하였고, 뚜껑 내부구조 및 향연구멍의 크기와 위치가 실제유물과 가장 유사한 정밀재현품을 이용하여 배연공과 흡기공의 크기와 개폐유무에 따라 분향실험을 진행하였다. 분향실험 결과, 배연공과 흡기공의 크기에 따라서는 아랫줄 흡기공이 향로의 불완전 연소에 영향을 끼치는 것으로 확인되었으며, 배연공과 흡기공의 개폐유무에 따라선 봉황 배연공과 윗줄 배연공은 주로 연기를 배출하는 역할을 하며 아랫줄 흡기공은 주로 흡기구 역할을 한다는 것을 이번 실험을 통해 알 수 있었다.

• 대한임상독성학회지
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• 제10권2호
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• pp.73-79
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• 2012

Purpose: The purpose of this study was to identify the changes in the characteristics of patients with carbon monoxide (CO) poisoning, as well as the distinctive differences in intentionally exposed patients. Methods: The medical records of CO poisoning patients, who visited nine emergency departments between January 2010 and December 2011, were reviewed retrospectively. The clinical information including age, gender, hospitalization, type of discharge, cause and location of exposure, site of onset, concentration of initial blood carboxyhemoglobin (COHb), methods of treatment and presence of neurological complications was examined. The subjects were divided into an intentional and non-intentional group and the differences between them was compared. Results: A total 209 subjects were recruited. The median age was 38 years (29~49.5 years). They frequently complained of nausea and vomiting, and the most common exposures occurred in winter, normally in the home. The cause of exposure was usually fire, followed by incomplete combustion of fuels. The median initial blood COHb was 13.15%. The proportion of intentionally exposed patients was 21%. They were significantly younger, more frequently discharged against medical advice, and showed a higher initial blood COHb level (22.85%) than the non-intentional group. Conclusion: This study suggests that those with intentional CO poisoning are normally discharged against medical advice even when they have a higher initial COHb level. An adequate explanation of the delayed neurologic sequelae and short term follow-up observation is recommended for those patients with intentional exposure.