• Reproductive and Developmental Biology
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• v.32 no.4
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• pp.229-235
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• 2008

Silencing of Dicer1 by siRNA did not inhibit development up to the blastocyst stage, but decreased expression of selected transcription factors, including Oct-4, Sox2 and Nanog, suggesting that Dicer1 gene expression is associated with differentiation processes at the blastocyst stage (Cui et al., 2007). In order to get insights into genes which may be linked with microRNA system, we compared gene expression profiles in Gapdh and Dicer1 siRNA-microinjected blastocysts using the Applied Biosystem microarray technology. Our data showed that 397 and 737 out of 16354 genes were up- and down-regulated, respectively, following siRNA microinjection (p<0.05), including 24 up- and 28 down-regulated transcription factors. Identification of genes that are preferentially expressed at particular Dicer1 knock down embryos provides insights into the complex gene regulatory networks that drive differentiation processes in embryos at blastocyst stage.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3413-3417
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• 2007

In recent semiconductor manufacturing clean rooms, air washers are used to remove airborne gaseous contaminants such as $NH_3$, SOx and organic gases from the outdoor air introduced into clean room. In the present study, an experiment was carried out to examine the improvement of removal efficiency for the gaseous contaminants. In order to improve the gas removal efficiency, a hot water contact heat exchanger was installed upstream of the air washer to heat and humidify the incoming outdoor air before entering the air washer.

• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.293-298
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• 2006

There are many researches in progress on co-firing of coal and biomass to reduce carbon dioxide produced from the coal consumption. This study carried out 200 Kg/h combustion test furnace by mixing coal with timber. Coal was mixed with domestic and imported-wood around 10% to 20% based on input energy. For the mixed fuel, combustion temperature, unburned carbon and the composition of flue gas were analyzed. In addition, the tendency of slagging and fouling was examined using a probe. According to the result of the experiment, combustion temperature was depended on the kind of wood and mixing ratio. The unburned carbon loss was higher with increase of wood biomass mixing ratio, as a result, the total heat loss of furnace was slightly increased. The emission of NOx and SOx were decreased by $3{\sim}20%$ and $21{\sim}60%$ respectively. There are no difference of slagging and fouling tendency between biomass co-firing and coal burning only.

• Journal of Energy Engineering
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• v.16 no.2
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• pp.73-82
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• 2007

World energy demand has been dramatically increasing because of using much energy of developing countries in Asia. The other side, conventional fossil fuels supply has been gradually decreasing due to the limitation of fossil fuel reserves and changing to the use of environmental-friendly energy for prevention the emission of carbon dioxide, NOx and SOx. Based on these times and status, we get the n necessity of the conversion of environmental-friendly energy and the high effective utilization of conventional and unconventional energy. Recently, promised DME fuel as environmental-friendly and substituted oils will be introduced the status of technology and market in domestic and foreign.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.207.1-207.1
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• 2010

The emission difference of SOx, NOx, TSP and dioxine was investigated in commercial CFB boiler, when coal and three kinds of RDFs were co-combusted respectively. The each mixing ratio was 7.5% RPF, 7.5% RDF and 10% SDF with coal. Emitting dioxine concentration was proportioned to the chlorine content of RDF. No trouble was found on normal boiler operation during co-combustion. These RPF, SDF and RDF could be determined to be a good alternative fuel of general coal.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.297-299
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• 2014

Petroleum coke has high heating value and low price. Due to the steadily increasing demand for heavy oil processing, the production volume of petroleum coke tends to be expanded. The high availability and low price of petroleum coke have been strongly considered as candidate fuel for power generation facilities. However the high carbon content, high sulfur content and nitrogen content of petroleum fuel are known to produce relatively large quantity of CO2, high NOx and SO2 emission. In this work, a series of numerical simulations have been carried out in order to investigate the effects of swirl flow intensity on combustion furnace, which is most important operating condition. Results show that the temperature distribution was spatially uniform at about 1600K but high temperature region are located quite differently depending on swirl number. In addition, numerical temperature data was compared with experimental temperature data and its temperature difference shows less than 10%. On the other hand, discrepancy between numerical and experimental emission data were slightly large with necessities of improved emission model.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.19-24
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• 1993

인간이 삶을 영위하기 위하여는 자연에서 끊임없이 자원과 에너지를 이용하여 일상생활에서 유용한 각종 제품을 생산하고 이를 사용하였다. 이러한 과정에서 인간에 유용한 각종 제품이외에 폐기물이 필연적으로 발생되어 자연을 오염시켰고 지구상에 인구가 많지 않았을 때에는 자연의 자정능력이 더커서 발생된 폐기물에 의한 환경오염의 문제는 발생되지 않았다. 따라서 인간은 활발한 경제활동에 의하여 더 많은 제품을 생산하고 더 많은 폐기물을 자연으로 방출하였다. 이러한 산업화와 더불어 도시화는 지구 생태계가 가진 자정능력의 한계를 훨씬 넘어 환경을 오염시켰다. 지구 전체적으로도 심각한 문제가 되는 CFC에 의한 오존층의 파괴, $CO_2$에 의한 지구온난화, SOx 및 NOx 등의 배출에 의한 산성비 그리고 산림의 황폐등이 심각한 오염문제로 대두되어 국경을 초월한 전세계적인 문제로 확대되어 "하나뿐인 지구"를 지키기위한 노력이 전세계인의 관심속에 합심하여 강구되고 있다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.337-338
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• 2003

대도시의 대기질은 1960년대 이후 지속되어온 국토개발과 성장위주의 경제모델이 각 도시 지형적 특성을 고려하지 못한 채 일률적으로 적용되면서 점차 심화되어 가고 있는 실정이다. 특히 1990년대 이후 연료정책 등 가시적인 효과를 거두고 있는 황산화물(SOx)도 도시권의 일부 지역에서는 인구유입에 따른 주택건설, 산업시설과 교통시설의 확충 등으로 절대량에 있어서 점차 증가추세를 나타내고 있다. 이러한 대도시에서의 대기질 현상을 규명할 수 있는 가장 객관적인 방법은 자동측정망의 활용이라 할 수 있으나, 수도권을 제외한 대도시에서의 대기측정망 수는 운영비용, 지역면적 및 인구밀도 등을 고려 할 때 현실적으로 부족한 실정이다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.53-54
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• 2003

현대 산업사회가 다양해짐에 따라 발생되는 생활폐기물의 형태도 다양화되었고 발생폐기물의 성상은 연소가 어려운 난분해성 폐기물로 발열량이 높아지고 있다. 이러한 폐기물의 처리를 위한 소각설비는 폐기물 처리형태에 따라 대형의 도시 쓰레기 소각장이나 지자체의 중형급 소각장, 발생원 단위의 소형 소각장으로 구분하여 처리하고있다. 기존 중ㆍ대형 소각로의 유해가스 처리시설은 일반적으로 냉각설비와 가스상 처리설비, 입자상 처리설비 등으로 구성되는데 반해, 소형 소각로는 싸이클론 방식만으로 구성되어 입자상 물질만을 처리하였으나, 최근에 들어서 관련법규가 개정되어 소형 소각로에서도 입자상 오염물질뿐만 아니라 HCl 및 SOx 등과 같은 산성가스류와 다이옥신 등의 배출농도를 규제함에 따라 가스상 오염물질도 처리하는 방안을 도입하고 있는 추세이다. (중략)

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.4
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• pp.364-367
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• 2006

In order to enhance the repair of defects in articular cartilage via cell therapy with autologous chondrocytes, as well as with periosteum-derived progenitor cells (PDPCs), silkworm hemolymph (SH) and a variety of cartilage-specific extracellular matrices (ECMs) including type II collagen, proline, chondroitin 4-sulfate, and chondroitin 6-sulfate were assessed with regard to their efficacy as media supplements. SH, a known anti-apoptotic agent, was found to enhance cell growth, as was shown by the results of a 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay. According to the results of reverse transcriptase polymerase chain reaction (RT-PCR) analyses, the cartilage-specific ECMs were found to stimulate the expression of hyaline cartilage-specific genes, most notably type II collagen and Sox9, in monolayer cultures of PDPCs.