• Journal of Korea Far Infrared Association
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• s.17
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• pp.17-24
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• 2003

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.176.2-176.2
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• 2011

피마자유(Castor oil)는 합성수지, 그리스, 유압용 오일, 윤활기유 등의 다양한 용도로 쓰이는 오일로서 점도가 높고 무색에서 황갈색을 띈다. 피마자유 추출은 압착 착유 또는 용매 추출로 얻게 되며 본 실험에 사용된 오일은 압착 착유한 것으로 매우 진한 갈색을 띄는 정제전 오일을 이용하였다. 실험에 사용된 피마자유의 초기 산가는 1mgKOH/g 이하로 낮은 유리지방산 함량을 보였으며 수분은 0.3%로 전이에스테르화 반응을 위해서는 수분 증발이 필요했다. 피마자유의 바이오디젤 생산을 위해 진행된 물성 분석 항목은 산가, 수분, 인함량, 황함량, 점도, 고형물이며 원료유와 그 바이오디젤에 대해 각각 물성 분석을 실시하였다. 피마자유의 가장 큰 특징은 다른 식물성 오일과는 다르게 오일이 알코올에 녹는 특성이 있으며 이런 이유로 전이에스테르화 반응 후 바이오디젤과 글리세롤이 분리되지 않는 문제점을 갖고 있다. 피마자유를 이용해 제조한 바이오디젤, 즉 지방산메틸에스터의 함량을 분석한 결과 약 90%의 메틸에스터화 반응 전환율을 나타내었으나 국내외 품질규격상의 탄소수 C14~C24:0의 지방산 에스터(fatty acid methyl esters)로 검출되는 바이오디젤의 함량은 10% 미만으로 나타났으며 나머지 90%는 라이신올레익산메틸에스터(ricinoleic acid methyl ester)로 분석되었다. 따라서, 기존의 대두유, 유채유, 팜유, 폐식용유로부터 제조한 바이오디젤과 물성이 매우 상이하고 특히 끊는점(boiling point)과 점도가 높아 경유 대체연료로는 활용이 불가능할 것으로 판단된다. 하지만 기존의 다양한 용도의 오일로 사용하기 위해 정제하는 과정에서 전체 착유 오일중의 약 10%만을 선택적으로 분리하여 바이오디젤 원료로 활용하는 방안은 가능할 것으로 판단된다.

• Korean Journal of Environmental Agriculture
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• v.26 no.1
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• pp.62-68
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• 2007

Concerns about endocrine disrupting chemicals emitted from humans and animals have been increased because these compounds are detected at very low levels in environment and adversely affect on indigenous fauna. To date, there is little information regarding the concentration of these compounds in animal wastes. In this study, the female hormones, $17\beta-estradiol$ (E2), estrone (E1) and estriol, were measured to provide baseline data in animal wastes. Samples were collected from animal waste storage, methane digester and sludge separated wastewater and analyzed by gas chromatography-mass spectrometry. To measure the mass ratios of estrogen to macronutrients, nitrogen and phosphorous were also determined. Sample collected from animal waste storage had the highest estrogen concentration (98.7 ${\mu}g/L$), while sludge separated wastewater had the lowest concentration (3.4 ${\mu}g/L$). The mean concentrations of E2 and E1 in waste storage sample were (6.8 ${\mu}g/L$) and (68.7 ${\mu}g/L$), respectively. In sludge separated wastewater, the mean concentration of both E2 and E1 were reduced to (2.6 ${\mu}g/L$) and (1.9 ${\mu}g/L$), respectively. However, estriol was not detected in any of the samples collected. Mean ratios of E2 and E1 to macronutrients were significantly different between the methane wastewater and sludge separated wastewater owing to elimination of solid particles.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.25-25
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• 2003

어류의 번식활동은 뇌-뇌하수체-생식소로 이어지는 내분비기관이 주로 담당하고 있으며, 그 중에서 뇌하수체에서 만들어지는 생식선자극호르몬 (GTH)은 생식소 발달에 매우 중요한 역할을 한다. 한편, GTH는 생식소에서 생성되는 스테로이드호르몬에 의해 유전자의 발현이 조절된다. 본 연구에서는 산천어 (Oncorhynchus masou)의 GTH 유전자발현에 미치는 estradiol-17$\beta$ (E2)의 영향을 생체내에서 먼저 조사하고, 유전자발현조절의 메카니즘을 구명하기 위하여 에스트로젠 수용체 (ER)의 cDNA를 cloning하였다. 또한 내분비교란물질로 알려져 있으며 에스트로젠 수용체와의 유사결합작용이 알려진 노닐페놀 (NP)의 영향도 아울러 조사하였다. 미성숙 산천어를 E2 및 NP (각각 5 mg/kg 및 10 mg/kg 체중)로 처리하면 72 시간째에 뇌하수체내의 $\beta$-actin mRNA에 비해 GTH (FSH$\beta$, LH$\beta$) mRNA가 상대적으로 증가하는 경향을 나타내었다. 뇌하수체에서 분리한 ER의 기본적인 구조는 DNA결합도메인 (Zf-C4), 호르몬결합도메인 (hormone_rec), 기타 전사활성화도메인으로 구성되어 있었으며 (그림 1), 기존에 보고된 에스트로젠 수용체중에서 무지개송어 및 대서양연어의 ER과 각각 98%, 96%의 높은 상동성이 관찰되었다. 향후, 준비된 ER을 재료로 하여 GTH 유전자발현의 호르몬의존성을 조사할 예정이다.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.237-242
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• 2000

We have synthesized ester compounds from the soybean oil and some Polymer alcohol compounds and studied the physical properties of the synthesized esters. We have performed this experiment for the purpose of testing the physical properties by soybean oil ester compounds as a water-soluble metal working lubricant.In addition, we have studied siy, surface tension, viscosity for the synthesized ester compounds in aqueous solution state varying the mixing ratio of water.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.318-323
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• 2010

아세틸콜린에스터라아제(AChE) 저해제에 의한 아세틸콜린 분해 억제는 알츠하이머 질병의 가장 확실한 치료 방법 중의 하나로 알려져 있다. 본 연구는 최근 웰빙 건강 소재로 각광을 받고 있는 과일과 채소로부터 새로운 AChE 저해제를 개발하여 항치매 식품이나 대체 의약품 생산에 응용하기 위해 과일과 채소로부터 AChE 저해 활성이 우수한 시료를 선별하고, AChE 저해 물질의 추출조건을 최적화하였다. AChE 저해 활성은 호두의 메탄올 추출물에서 72.6% ($IC_{50}=14.2\;{\mu}g$)로 가장 높았고, 호두의 AChE 저해 물질은 80% 메탄올로 $40^{\circ}C$에서 12시간 동안 처리하였을 때 가장 많이 추출되었다.

• Research in Plant Disease
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• v.20 no.2
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• pp.95-100
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• 2014

This research was performed to examine the effects of mixed espil and copper hydroxide for powdery mildew prevention on cucumber, tomato and pepper. On prevention effect for powdery mildew on cucumber, results revealed that mixed espil and copper hydroxide with a ratio of 4 : 1, disease incidence rate was 18.9% and prevention effect was 69.9%. Another treatment with a ratio of 8 : 1 showed an disease incidence rate of 18.1% and prevention effect of 71.1%, thus, showed great effectiveness. For powdery mildew on tomato, espil and copper hydroxide were mixed using the ratio 4 : 1, results showed an disease incidence rate of 12.4% and prevention effect of 85.3%. Treatment using the ratio of 8 : 1, results showed an disease incidence rate of 14.3% and prevention effect of 83.0%, thus, showed great effectiveness. For powdery mildew on redpepper, espil and copper hydroxide were mixed using the ratio of 4 : 1 with results showed disease incidence rate of 17.7% and prevention effect of 83.0%. From the results, this treatment is the most effective with the lowest attack rate and highest prevention effect. Deducing from the study, it was found out that using mixed espil and copper hydroxide using the ratios 4 : 1 or 8 : 1 are the most effective method for powdery mildew prevention. Mixed ratio of 4 : 1 or 8 : 1 was most effective for preventing powdery mildew on cucumber and tomato, while the espil and copper hydroxide ratio of 4 : 1 was the most effective method for powdery mildew prevention on pepper.

• Applied Chemistry for Engineering
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• v.24 no.1
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• pp.72-76
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• 2013

In this study, the boric acid which is a by-product in the esterification process to obtain norbornene diester derivatives was recovered, and then its reusability for esterification of norbornene was investigated. Four types of trialkyl borate (tributyl borate, tripentyl borate, and triisopentyl borate, trihexyl borate) were synthesized through the esterification with boric acid and four types of alcohol. Then, diester derivatives were synthesized by esterification with the synthesized trialkyl borate and norbornene dicarboxylic acid. The conversion of norbornene dicarboxylic acid is 89.50~99.31%. The boric acid which is a by-product in the esterification were recovered with NaCl salt and used for synthesizing trialkyl borate. The recovery rate was 92.43~99.35 %. When the recovered trialkyl borate was used in esterification, there are little losses of the yield. Since boric acid which is a major by-product is able to be recovered, the process is expected to be a clean technology to prevent an environmental pollution by the emission of chemical compounds.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.313-315
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• 2005

비이온성 계면활성제의 화학적 구조에 따른 리모넨의 유화분산시 입경변화와 세정성을 비교검토한 결과 리모넨과 계면활성제의 사용비가 30:1의 소량을 사용하여도 충분한 세정성을 보였으며, 에스테르 구조를 가진 계면활성제가 유화능력이 우수하여 에멀젼 입경이 작고 접착력은 크며, 접촉각이 작아 가장 우수한 세정성을 나타내었다. 그리고 에테르 구조의 계면활성제간 비교로부터 방향족 고리 구조보다 지방족 사슬구조가 에멀젼의 입경이 작고 세정성이 우수하였다. 에멀젼의 안전성은 에스테르계가 가장 우수하였다.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.162-177
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• 2001

The hydrolysis rates of seven kinds of polyol ester base oils 〔POEs〕 of different branch shape were investigated by using a simple apparatus under mild acidic condition. Seven polyol ester base oils were made of poly hydric alcohols of two-four valence, normal or branched fatty acids of different carbon number. p-Toluene sulfonic acid was used as acid catalyst to accelerate the rate of hydrolysis. Partial esters and fatty acid produced by sequential hydrolysis of POEs were identified and their concentrations were determined by calibrated-internal standard method using Gas Chromatography. The rate constants of each step in sequential hydrolysis were determined by the least square method from rate equation and the concentration of each component, were compared with one another. It was shown that the rate of hydrolysis of POEs was strongly affected by whether molecular structure of fatty acid was straight chain or branch chain and which position was branched. The hydrolysis stability for all the POEs can be reasonably explained by using a steric hindrance effect anticipated fi:om their molecular structures affecting as water molecule makes an attack on the carbonyl carbon of POEs.