• Journal of Power System Engineering
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• v.12 no.1
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• pp.5-12
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• 2008

We measured emission characteristics of CRDI diesel engine equipped with a commercial CPF. Experimental parameters adopted a neat diesel fuel, a blend of diesel fuel with 20% biodiesel, a blend of diesel fuel with 15% biodiesel and 5% ethanol. The experiments were carried out to measure the emission and engine performance according to ESC 13-mode cycles. The maximum torque with biodiesel blend fuel is slightly lower than that of neat diesel fuel in the entire the 13-mode cycles, and 5% ethanol and 15% biodiesel blend fuel is slightly higher than that of neat diesel fuel. THC and CO emissions of the biofuel blended diesel fuel were slightly increased and decreased, and mean conversion efficiencies of THC and CO on the commercial CPF were achieved about 70$\sim$87% in the ESC 13-mode. From the measurement by the Scanning Mobility Particle Sizer(SMPS), the total number and mass of nano-sized particles by a commercial CPF were decreased about 97.8% and 96.8 % in the range of the nano-size from 10.6 to 385nm, respectively.

• Journal of the Korean Wood Science and Technology
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• v.18 no.3
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• pp.69-76
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• 1990

$^1H$ 및 $^{13}C$ 핵자기(核磁氣) 공오(共嗚) 분광기(分光器), 적외선(赤外線) 흡광(吸光) 분광기(分光器)와 질량분석기(質量分析器)를 이용(利用)하여 설폰화(化) 반응(反應)의 한 반응물(反應物)이 단리(單離)되어 구조적(構造的)으로 규명(糾明)되었다. 그 화합물(化合物)은 에탄올 및 에탄올 수용액(水溶液)을 용매(容媒)로 사용(使用)하여 Sephadex LH-20상(上)에서의 반복적(反復的)인 컬럼 크로마토그래피로 단리 및 정제(精製)되었다. 규명된 화합물은 이전에 보고(報告)된 바 없는 새로운 구조의 disodium epicatechin-(4${\beta}$, 5')-disulfonate였다. 이 화합물은 온화(溫和)한 설폰화(化) 조건하(條件下)에서 최초(最初)의 친전자(親電子) 치환(置換)의 예(例)로서 catechol B 환구조(環構造)가 quinone methide 중간물(中間物)을 생성(生成)하는 한 반응기구(反應機構)가 제시(提示)되었다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.131-131
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• 2018

중국(中國) 장홍화(藏紅花)는 해발 1500m~3000m에 자생하는 고원식물이다. 장홍화는 여성질환예방과 두뇌의 신경안정, 호르몬분비 촉진, 학습증진과 기억력향상에 의한 알츠하이머 치료의 효과가 있는 것으로 알려져 있으며, 함유되어 있는 크로신은 암세포를 파괴시키어 종양세포를 줄이는 작용을 하며, 카로티노이드 성분이 항산화 활성과 면역을 증진시키어 항암효과를 가져다 준다. 또한 다량의 칼륨을 함유하고 있어서 나트륨배출에 효과적이어서 혈압을 떨어뜨리는 작용을 한다. 또한 신경전달물질의 활동을 증진시키어서 스트레스 해소와 치매 및 인지력을 높여준다고도 알려져 있다. 본 실험에서는 장홍화(藏紅花)추출액의 총 폴리페놀 함량과 항산화 물질 활성을 조사했던 바, 장홍화(藏紅花) 메탄올과 에탄올추출액에서 항산화 반응이 매우 양호하였다. 또한 총 폴리페놀 함량도 에탄올 추출물과 메탄올 추출물 처리구에서도 비슷한 결과를 나타내었다. 이러한 결과들로 미루어 볼 때 장홍화(藏紅花)의 추출액은 건강음료와 화장품의 기능성원료로도 이용이 가능할 것으로 추측되었다.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.2003-2005
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• 2002

바이오 마이크로 시스템 및 바이오 MEMS 분야, 특히 실리콘을 기질로 하는 바이오 센서 제작에서 반도체 공정 기술은 센서의 대량 생산과 초소형화를 위해서 반드시 필요한 기술이다. 그러나, 감지전극의 마이크로화에 따른 센서의 감도 및 안정성 저하 문제는 해결해야 할 과제이다. 최근, 다공질 실리콘이 갖는 대면적이 실리콘 기질과 생체 고분자 (예: 단백질, 핵산 등) 간의 결합력을 향상시킬 수 있음이 알려지면서, 바이오 센서 분야에서, 새로운 형태의 드랜스듀서 재료로서의 다공질 실리콘에 대한 논의가 활발히 전개되고 있으며 또한, ISFET (Ion-Selective Field-Effect Transistors) 와는 달리 다공질 실리콘 층은 저항이 크기 때문에 센서 제작 과정에서의 부가적인 절연막을 필요로 하지 않는다. 본 연구에서는, 백금을 증착한 다공질 실리콘 표면에 전도성 고분자로서 Polypyrrole (PPy) 필름과 생체 고분자 물질로서 Urease를 각각 전기화학적으로 흡착하였다. 다공질 실리콘 층의 형성을 위해 테플론 소재의 전기화학 전지에 불산 (49%), 에탄올 (95%), $H_2O$ 혼합 용액을 넣고 실리콘 웨이퍼에 일정시간 수 mA의 산화 전류를 흘려주었으며, 약 $200{\AA}$의 티타늄 박막과 $200{\AA}$의 백금 박막을 RF 스퍼터링하여 작업 전극을 제작하였고, 백금 박막 및 Ag를 기화 증착하여 제작한 Ag/AgCl 박막을 각각 상대 전극과 기준전극으로 하였다. 박막 전극의 표면 분석을 위해 SEM (Scanning Electron Microscopy), EDX (Energy Dispersive X-ray spectroscopy) 등을 이용하였다. 제작된 요소 센서로부터 요소 농도 범위 0.01 mmol/L ${\sim}$ 100 mmol/L에서 약 0.2 mA/decade의 감도를 얻었다.

• Economic and Environmental Geology
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• v.46 no.6
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• pp.593-602
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• 2013

Biodiesel is an important new alternative transportation fuel and it can be produced by chemically reacting a fat or oil with an alcohol, in the presence of a catalyst. The product of the reaction is a mixture of methyl esters, which are known as biodiesel, and glycerol, which is a high value co-product. The process is known as transesterification. Biodiesel can be used neat and when used as a pure fuel it is known as BD100. However, it is often blended with petroleum-based diesel fuel and when this is done the blend is designated BD5 or BD20(BD20 is a blend of 20% biodiesel and 80% petroleum diesel fuel). Adherence to a quality standard is essential for proper performance of the fuel in the engine and will be necessary for widespread use of biodiesel. In this study, we analyzed 4,144 papers of biodiesel by category, country, institution, keyword etc. from 2001 to 2013 years.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.622-628
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• 2016

This study investigated to understand the trend of international commercializing technologies and industrial status of the transportation biofuel based on lignocellulosic biomass. Two major commercializing technologies for the lignocellulosic biofuel are biochemical conversion technology and thermochemical conversion technology. It was reported that a total of 93 industrial companies were using lignocellulosic biomass of all facilities related to advanced biofuel. On the basis of commercial type, the biochemical conversion technology was identified to be the major technology in the lignocellulosic biofuel industries, showing 84% of all. Also the main products of commercial type industrial companies are bioethanol (1,155,000 tons/yr) and bio-oil (120,000 tons/yr), which are in a remarkably inadequate amount to substitute for the transportation biofuel worldwide. It was suggested that the transportation biofuel market was currently in need of further development in both technology and scale, and was in high demands of technological development and commercializing exertion.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.1-10
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• 2007

This study was reviewed on the bioethanol production from biomass resources and feedstock supply in America. U.S. Department of Energy (USDE) and the u.s. Department of Agriculture USDA) are both strongly committed to expand the role of biomass as an energy source. They support biomass fuels and products as a way to reduce the need for oil and gas imports, to strengthen the nation's energy security and environmental quality. And it was envisioned a 20 percent replacement of the current U.S.transportation fuel consumption in 2030. Also it was reviewed policies to encourage the expanding of Bio-based fuel use to replace gasoline, such as Clean Air Act, Federal Clean Fuel Program and American Jobs Creation Act. In feedstock supply it was assumed forest biomass will be supplied in 368 million dry tons yearly and the agriculture derived biomass adopted by new technologies and land use change will be supplied in 998 million dry tons, including highly 818 million dry tons of lignocellulosic biomass such as perenial crops (hybrid trees, grasses) corn stover, other crop residues. This amount is 5 times to the amount from based current agricultural technology and crop land.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.2
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• pp.250-258
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• 2020

This study was conducted to analyze the impact of low level bio-alcohols that can be applied without modification of vehicles to improve air quality in Korea. The emissions and fuel economy of low level bio-alcohols mixed gasoline fuels of spark ignition vehicles, which are direct injection and port fuel injection, were studied in this paper. As a result of the evaluation, the particle number (PN) was reduced in all evaluation fuels compared to the sub octane gasoline without oxygen, but the correlation with the PN due to the increase in the oxygen content was not clear. In the CVS-75 mode, emitted CO tended to decrease compared to sub octane gasoline, but no significant correlation was found between NMHC, NOx and fuel economy. In addition, it was found that the aldehyde increased in the oxygenated fuel, and there was no difference in terms of the amount of aldehyde generated among a series of bio-alcohol mixed fuels.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.250-256
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• 2013

Gasoline generates organic acid and polymer (gum) by hydrocarbon oxidation depending on the storage environment such as temperature and exposure to sunlight, which can cause metal corrosion, rubber and resin degradation and vehicle malfunction caused by accumulation in fuel supply system. The gasoline which has not been used for a long time in bi-fuel (LPG-Gasoline) vehicle causes problems, and low octane number gasoline have evaporated into the field, but the exact cause has not been studied yet. In this study, we suggest a plan of quality management by investigating the gasoline oxidation behavior. In order to investigate the oxidation behavior of gasoline, changes of gasoline properties were analyzed at various storage conditions such as storage time, storage vessel type (vehicle fuel tank, PE vessel and Fe vessel) and storage circumstances (sunlight exposure and open system, etc.). Currently distributing gasoline and bioethanol blended fuel (blended 10%) were stored for 18 weeks in summer season. The sample stored in PE vessel was out of quality standard (octane number, vapor pressure, etc.) due to the evaporation of the high octane number and low boiling point components through the vessel cap and surface. Especially, the sunlight exposure sample stored in PE vessel showed rapid decrease of vapor pressure and increase of gum. Bioethanol blended fuel showed similar results as gasoline.

• Journal of agriculture & life science
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• v.44 no.3
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• pp.61-67
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• 2010

This study was conducted to investigate the antioxidant activities and ginsenoside compositions of 4-year-old cultured ginseng roots (4CGR), 4-year-old mountain ginseng roots (4MGR) and leaves (4MGL), and 8-year-old mountain ginseng roots (MGR) and leaves (8MGL). Ginseng root and leaves were extracted with water and 80% ethanol. Crude saponin content of 4CGR was 3.85% (d.b.) and the contents of 4MGR, 4MGL, 8MGR and 8MGL were 6.75, 8.57, 6.53 and 7.54% (d.b.), respectively. 4CGR showed the highest content of ginsenoside-$Rh_1$ (6.07 mg/g), 4MGR showed the highest content of ginsenoside-$Rb_1$ (11.63 mg/g), 4MGL showed the highest content of ginsenoside-Re (24.35 mg/g), 8MGR showed the highest content of ginsenoside-$Rh_1$ (19.77 mg/g), and 8MGL showed the highest content of ginsenoside-Re (20.43 mg/g). Total antioxidant activity (AEAC) was ranged from 5.56 at 4MGR to 20.67 mg AA eq/g at 8MGL.