• Title/Summary/Keyword: large source

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Large-scale synthesis of the carbon coils using stainless steel substrate

  • Jeon, Young-Chul;Kim, Sung-Hoon
    • 한국결정성장학회지
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    • 제23권6호
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    • pp.296-301
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    • 2013
  • Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under the thermal chemical vapor deposition system. A 304-type stainless steel was used as a substrate with nickel powders as the catalyst. The surface of the substrate was pretreated using a sand paper or a mechanical drill to enhance the production yield of the carbon coils. The characteristics of the deposited carbon nanomaterials on the substrates were investigated according to the surface state on the stainless steel substrate. The protrusion induced by the grooves on the substrate surface could enhance the formation of the carbon nanomaterials having the coils geometries. The cause for the enhancement of the carbon coils formation by the grooves was suggested and discussed with the surface energies for the interaction between as-growing carbon elements. Finally, we could obtain the massive production yield of the carbon coils by the surface pretreatment using SiC sand papers on the several tens grooved stainless steel substrate.

해양온도차 발전을 위한 심층수 파이프 직경에 따른 에너지 손실량 검토 (Feasibility Study on Cold Water Pipe Diameter by Friction Loss and Energy Conversion on OTEC)

  • 정훈;허균영
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 추계학술대회 초록집
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    • pp.170-170
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    • 2010
  • The energy conversion from the temperature difference between hot and cold source like ocean thermal energy conversion (OTEC), requires a long and large-diameter pipe (about 1000 to 10,000 meters long) to reach the deep water. The pipe diameter ranges from 2.8 meter for proposed early test systems, to 5 meter for large, commercial power generation systems. The pipe must be designed to resist collapsing pressures produced by water temperature and density differences, and the reduced pressure required to induce flow up the pipe. Other design considerations include the external-drag effect on the pipe due to ocean currents, and the wave-induced motions of the platform to which the pipe is attached. Various approaches to the pipe construction have been proposed, including aluminum, steel, concrete, and fiberglass. More recently, a flexible pipe construction involving the use of fiberglass reinforced plastic has been proposed. This report presents the results of a scaled fixed cold water pipe (CWP) model test program performed by EES(Engineering Equation Solver) to demonstrate the feasibility of this pipe approach.

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오리를 이용한 한방식품 추출액이 흰쥐의 지질함량에 미치는 영향 (Effect of Duck Extract on Lipids in Rats)

  • 김정선;김우경
    • Journal of Nutrition and Health
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    • 제36권1호
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    • pp.3-8
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    • 2003
  • The aim of the present study was to investigate the effect of duck extract on lipids. Rats in the experimental group were orally administered with duck extract for four weeks. The half of the supplementation was composed of duck meat and the other of the supplementation was composed of oriental herbs. Weight gain, diet intake, and food efficiency ratio were compared between control and experimental groups. Organ weight, lengths of small/large intestines, and the following plasma biochemical parameters were also measured: hemoglobin, hemoglobin, GOT, GPT, blood glucose concentration, lipids of plasma, liver, feces. Spleen index (weight/100 g body weight) of the rats in the experimental group was significantly higher than those in the control group due to increase in fat intake from the supplementation of duck meat. The large intestines of the rats in the experimental group was significantly larger due to the supplementation with dietary fiber derived from herbs in the extract. There were significant higher levels of plasma hematocrit, GOT, total cholesterol, and HDL-cholesterol in the rats of the experimental group. From the results, although duck meat is a source of animal food, the fat profile of duck extract, such as the ratio of polyunsaturated fatty acids to saturated fatty acids appears to be beneficial to human health. These findings suggest a possible anti-hyperlipidemic effect of duck extract. (Korean J Nutrition 36(1): 3∼8, 2003)

Near-Infrared Polarization Source Catalog of Northeastern Regions in the Large Magellanic Cloud

  • Kim, Jaeyeong;Jeong, Woong-Seob;Pak, Soojong;Park, Won-Kee;Tamura, Motohide
    • 천문학회보
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    • 제40권2호
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    • pp.31.2-31.2
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    • 2015
  • We present a near-infrared photometric and polarimetric catalog of sources in the $39^{\prime}{\times}69^{\prime}$ fields on the northeastern part of the Large Magellanic Cloud (LMC), which was observed using SIRPOL, an imaging polarimeter of the Infrared Survey Facility (IRSF). This catalog contains 1,858 sources brighter than 14 mag at H band with polarization signal-to-noise ratio greater than 3 in at least one of J, H, and Ks bands. We examined the polarization structures around the star-forming regions, where coherent polarization position angle distributions are seen. We also estimated magnetic field strengths in some selected fields using Chandrasekhar and Fermi analysis. The magnetic field strengths are estimated to be $3{\sim}25{\mu}G$. The wavelength dependence of polarization degrees indicates that the polarization is most likely to be originated from dichroic extinctions by the local interstellar dusts in the LMC. We found that the polarization patterns are well aligned along the molecular clouds around star-forming regions.

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한국의 EIA 자료와 그의 활용 (Data for EIA and Its Presentation in Korea)

  • 이현영
    • 환경영향평가
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    • 제2권2호
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    • pp.73-83
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    • 1993
  • Increasing concern for the environment in Korea has led to the demand that major policies and large-scale development projects be subjected to detailed impact assessment. This paper reports on the state of data related to the prediction of the environmental impact (EIA) to emphasize the importance of data quality. Environmental impact statements (EIS) consulted with the Ministry of Environment of Korea were analyzed from 1981 through 1992. Many of assessors used existing data and collected supplementary data from field survey. Most of the results of EIA are presented directly or summarized on maps and as graphics. For the national purpose, large source of quality-controlled data such as atmospheric data have been developed, However, there are the deficiency in data to analyze the impact of human activity, and data gaps and incompatibilities among systems. Consequently, the development of data bank systems including computer database and remotely-sensed satellite data is required to improve the quality of data which are relevant to EIA. The data bank system should be organized meaningfully in minimum time with a least cost, and measurement standards must be made explicit. Geographical information systems (GIS) are applicable to the graphic presentation or to the impact prediction model.

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소하천의 오염부하량이 수질에 미치는 영향에 관한 연구 (A Study about the Influence of Pollutant Load on Water Quality in a Small Stream Watershed)

  • 이상훈;조욱상
    • 환경영향평가
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    • 제10권1호
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    • pp.9-19
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    • 2001
  • An intensive watershed survey including water quality measurement of 6 times was carried out in order to find out the relationship between pollutant load and water quality in a small stream watershed where livestock wastewater is the main source of water pollution. The findings from the survey are as follows. 1) The number of livestock showed large disagreement among county office, myon, and insite survey. It is vital to check the data at the beginning of watershed survey. 2) The fluctuation of streamflow and water quality was so large depending on the day of measurement that it is essential to set up continuous telemetering system to get reliable data about delivery ratio of pollutants. 3) It was helpful for setting the priority of investigation to check water quality and quantity at several points along the stream after dividing the watershed into 5 drainage areas. 4) To control the livestock wastewater, especially in case of cows, it is necessary to have roof system and prevent overland flow from the ground. In case of pig farms, it is recommended to have public treatment system instead of private treatment system. The exact emission load of livestock wastewater was difficult to estimate, and requires more study.

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아파트 마감재의 연기 유독성 (A Toxicity of Interior Upholstery in Apartment Housing)

  • 함상근;김홍;한상범;김운형
    • 한국화재소방학회논문지
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    • 제15권3호
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    • pp.36-43
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    • 2001
  • 아파트 내장재 중 마감재로 사용되는 벽지, 목재합판 및 장판 등을 사용하여 LOl(Limit Oxygen Index)와 NES 713의 측정방법으로 연소가스 방출특성을 고찰한 결과 난연 벽지, 장판 등의 난연성은 우수하였으나, 난연 벽지의 경우 점화원이 지속적으로 제공이 되어지면 유독가스를 많이 배출하였다. 장판, 벽지 및 합판을 질량별로 연소특성을 고찰한 결과 단일 CO의 양은 벽지가 가장 많이 측정되었으나 CO/Mass loss는 장판이 가장 높게 나타났다. 따라서 장판의 경우 연소시 적은 양의 연소로도 많은 유독성 가스를 방출할 수 있음을 알 수 있었다

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유기성폐기물을 이용한 바이오가스 생산 및 활용기술 (Biogas Production and Utilization Technologies from Organic waste)

  • 허남효;이승헌;김병기
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.202-205
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    • 2008
  • Anaerobic digestion(AD) is the most promising method of treating and recycling of different organic wastes, such as OFMSW, household wastes, animal manure, agro-industrial wastes, industrial organic wastes and sewage sludge. During AD, i.e. degradation in the absence of oxygen, organic material is decomposed by anaerobes forming degestates such as an excellent fertilizer and biogas, a mixture of carbon dioxide and methane. AD has been one of the leading technologies that can make a large contribution to producing renewable energy and to reducing $CO_2$ and other GHG emission, it is becoming a key method for both waste treatment and recovery of a renewable fuel and other valuable co-products. A classification of the basic AD technologies for the production of biogas can be made according to the dry matter of biowaste and digestion temperature, which divide the AD process in wet and dry, mesophilic and thermophilic. The biogas produced from AD plant can be utilized as an alternative energy source, for lighting and cooking in case of small-scale, for CHP and vehicle fuel or fuel in industrials in case of large-scale. This paper provides an overview of the status of biogas production and utilization technologies.

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Production and characterization of a monoclonal anti-glutathione-S-transferase(GST) antibody

  • You, Je-Kyung;Shin, Chan-Young;Park, Kyu-Hwan;Ko, Kwang-Ho
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1997년도 춘계학술대회
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    • pp.93-93
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    • 1997
  • Analysis of protein is often frustrated by the inability to isolate large amounts of purified protein from a native source. To overcome this problem, fusion protein expression systems such as pGEX system have been widely used. Using pGEX system, the desired protein could be easily obtained in a large amount in E. coli, and then the fusion protein could be used for the study of the function of the given protein. To analyze and purify the GST fusion protein, anti-GST antibody could be used as one of the system of choice. However, the production and characterization of monoclonal anti-GST antibody has not been studied extensively yet. To produce monoclonal anti-GST antibody, GST was purified from E. coli transformed with pGEX-cs, one of the pGEX system and was used as an antigen. The monoclonal antibody was produced by fusion of the immunized spleen cells with SP2-0 myeloma cells. The antibody was characterized by ELISA, western blotting, etc. The monoclonal antibody produced in this study (mAb-GSTA) showed strong and specific immunoreactivity against not only GST but also GST-fusion proteins. Also, mAb-GSTA was successfully used for the immunoaffinity purification of the GST ${\beta}$-Rc.-third intracellular-loop fusion protein. The results of the present study suggest that mAb-GSTA may be used for the identification and purification of GST fusion proteins.

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초고온가스원자로 열원 SI 공정을 이용한 원자력수소생산시스템 비용 예비 분석 (Preliminary cost estimation for large-scale nuclear hydrogen production based on SI process)

  • 양경진;최재혁;이기영;이태훈;이경우;김만응
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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    • pp.723-726
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    • 2009
  • As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GT-MHR are estimated in the necessary input data on a Korean specific basis. G4-ECONS developed by EMWG of GIF in 2008 was appropriately modified to calculate the cost for hydrogen production of SI process with VHTR as a thermal energy source rather than the LUEC. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if $CO_2$ capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of $CO_2$. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed.

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