• 한국분무공학회지
• /
• 제14권3호
• /
• pp.122-130
• /
• 2009

Vegetable oil and its derivatives as an alternative diesel fuel have become more attractive recently because of its environmental benefits and the fact that they are made from renewable resources. Viscosity is the most significant property to affect the utilization of vegetable oil and its derivatives in the compression ignition engines. This paper presents the existing correlations for predicting the viscosity of vegetable oil and its derivatives for compression ignition engines. According to the parameter considered in the correlations, the empirical correlations can be divided into six groups: correlations as a function of temperature, of proportion, of composition, of temperature and composition, of temperature and proportion, and of fuel properties. Out of physical properties of fuel, there exist in the literature several parameters for giving the influence on kinematic viscosity such as density, specific gravity, the ratio of iodine value over the saponification value, higher heating value, flash point and pressure. The study for the verification of applicability of existing correlations to non-edible vegetable oil and its derivatives is required.

• 한국분무공학회지
• /
• 제16권1호
• /
• pp.15-26
• /
• 2011

In this article, spray characteristics in CI engines fuelled with vegetable oils and its derivatives will be reviewed. Of edible vegetable oils, soybean oil and rapeseed oil were mainly investigated. Of inedible vegetable oils, jatropha oil and used frying oil were main concern on the research on the spray characteristics in CI engine. Spray angle and spray penetration were mainly examined among the macroscopic spray characteristics and Sauter mean diameter was only investigated among the microscopic spray characteristics. There exist six different definitions of spray angle which should be examined. Neat vegetable oil and biodiesel fuels show smaller spray angle than diesel fuel. Biodiesel fuel and vegetable oils and its blend have a longer spray penetration than diesel fuel. However, biodiesel blends with diesel shows the similar spray penetration with diesel fuel. SMDs in the biodiesel spray, vegetable oils and its blends spray are higher than that in the diesel spray.

• 약학회지
• /
• 제46권2호
• /
• pp.89-92
• /
• 2002

Allylthio group of the sulfur compounds of garlic oil plays an important role for prevention and treatment of hepatic diseases induced by toxic substances or carbon tetrachloride. Thus allylthio group as pharmacologically active group was introduced into pyridazine heterocycle ring. Aryloxyallylthiopyridazine derivatives were synthesized and their hepatoprotective activities were screened in rat. The activities of these compounds were weaker than alkoxyallylthiopyridazine derivatives, which exhibit a superior hepatoprotective effect.

• 한국식품영양과학회지
• /
• 제36권9호
• /
• pp.1120-1127
• /
• 2007

n-6계 linoleic acid의 함량이 높은 옥수수유 및 n-3계 linolenic acid의 함량이 높은 들깨유와 함유된 다가불포화지방산을 공역이중결합 유도체화 처리한 옥수수유 및 들깨유가 흰쥐의 혈청 지질개선에 미치는 영향을 비교 검토하기 위하여 S.D.계 숫 흰쥐에게 돈지 식이를 대조군으로 하고 옥수수유 10%, 들깨유 10%, 유도체화 처리한 옥수수유 10% 및 유도체화 처리한 들깨유 10%을 급여하여 4주간 실험 사육한 후 혈청 지질성분을 분석하였다. 유도체화 처리한 옥수수유(TCO)는 가스 크로마토그래피에 의해 3개의 linoleic acid의 유도체가 확인되었고 유도체화 처리한 들깨유(TPO)에서는 5개의 linolenic acid의 유도체가 확인되었다. 체중증가량 및 식이섭취량은 유도체화 처리한 옥수수유 및 들깨유 급여군에서 유의성 있게 낮았다. 혈청 총콜레스테롤 농도는 대조군에 비해 전실험군에서 유의성 있게 낮았으며, 특히 유도체화 처리한 옥수수유 및 들깨유 급여군에서 더욱 낮았다. HDL-콜레스테롤 농도는 대조군에 비해 전실험군에서 유의적으로 높았다. 혈청 LDL 및 LDL-콜레스테롤 농도는 대조군에 비해 전실험군에서 유의성 있게 낮았으며 유도체화 처리한 옥수수유 및 들깨유 급여군에서 더욱 낮은 경향을 보였고, 특히 유도체화 처리한 들깨유 급여군에서 가장 낮았다. VLDL 농도는 대조군에 비해 전실험군에서 유의성 있게 낮았으며, chylomicron 농도는 유도체화 처리한 유지 급여군에서 유의성 있게 낮았고 특히 유도체화 처리한 들깨유 급여군에서 가장 낮았다. 혈청 유리콜레스테롤 농도는 대조군에 비해 전 실험군간에 유의적인 차이는 없는 반면 유도체화 처리한 옥수수유 및 들깨유 급여군에서 약간 낮았다. 혈청 중성지질 농도는 대조군에 비해 전실험군에서 유의성 있게 낮았으며, 특히 유도체화 처리한 들깨유 급여군에서 가장 낮았다. 인지질 농도는 옥수수유 급여군이 대조군에 비해 약간 높게 나타난 반면 유도체화 처리한 유지 급여군은 약간 낮은 수준이었다. 이상의 결과 n-6계 linoleic acid의 함량이 높은 옥수수유 및 n-3계 linolenic acid 함량이 높은 들깨유의 공역이중결합유도체의 섭취는 혈중 총콜레스테롤, LDL-콜레스테롤, chylomicron 및 중성지질 농도를 감소시킴으로써 혈청 지질 개선효과가 있는 것으로 나타났으며, 특히 n-3계 들깨유의 공역이중결합 유도체 급여군이 혈청 지질 개선효과가 가장 큰 것으로 나타났다.

• 청정기술
• /
• 제17권3호
• /
• pp.238-243
• /
• 2011

본 연구에서는 폴리우레탄을 위한 친환경 폴리올 합성을 위하여 피마자유 기반의 폴리올을 합성하였다. 피마자유의 2차 알콜에 다른 촉매 없이 무수말레산을 이용하여 카르복실기를 도입하고, 이를 1차 알콜로 전환하기 위하여 아미노알콜($H_2N$-R-OH) 유도체를 반응시켜 친환경 폴리올을 제조하였다. 다양한 비율의 피마자유와 무수말레산의 반응이 시험 되었으며, 전체 반응은 상대적으로 낮은 공정온도와 무촉매 반응을 기반으로 수행되었다. 긴 곁가지가 도입되어 유동성을 가지고 있는 피마자유 기반의 천연폴리올이 기존의 합성폴리올과 가장 우수한 상용성을 나타내었다.

• 한국응용과학기술학회지
• /
• 제4권2호
• /
• pp.19-23
• /
• 1987

The addition of dipeptides and 1,2-bis (aminoacyl) hydrazine derivatives a level of 250 ppm to corn oil resulted in the retardation of the oxidaitive deterioration of the oil when it was stored in the oven at $70^{\circ}C$ during 5 days. Their antioxidant activities were investigated by UV absorbance of the corn oil at the wavelength of 234nm. 1,2-bis (aminoacyl) hydrazine derivatives showed higher antioxidant activity than normal dipeptides. Dipeptides containing phenyl ring with which is conjugable a-carbon radical showed antioxidant activity.

• 한국응용과학기술학회지
• /
• 제3권1호
• /
• pp.43-47
• /
• 1986

1.2-bis(aminoacyl)hydrazine derivatives and dipeptides were synthesized by conventional peptide synthesis procedures. Their antioxidant activity were inverstigated by over-storage test using corn oil as substrte. 1.2-bis (aminoacyl) hydrazine derivatives and dipetides containing hydrophobic side chain amino acid showed higher antioxidant activity. A free N-terminal amino group was also found to be important for the appearance of antioxidant activity. 1.2-bis (aminoacyl) hydrazine derivatives showed higher antioxidant activity than dipeptides. Antimicrobial activites of dipeptides and 1.2-bis (aminoacyl) hydrazine derivatives were also examined by the paper disc method. All of these compounds had shown no antimicrobial activity.

• 공업화학
• /
• 제24권5호
• /
• pp.530-536
• /
• 2013

경유의 윤활성향상제로 사용하기 위하여 식물유 기반 다이머산 유도체를 합성하여 윤활성능을 평가하였다. 다이머산 유도체의 합성은 2단계의 반응을 거쳐 합성하였는데, 1단계 반응으로 폐식물유(다크오일)를 가수분해반응을 통하여 합성한 지방산을 사용하여 고온에서 디엘스-알더 반응을 행하여 다이머산을 합성하였다. 2단계 반응으로 합성한 다이머산을 사용하여 메탄올과 에스테르화 반응을 행하여 다이머산 유도체를 합성하였다. 합성한 다이머산 유도체는 1 wt% 범위 내에서 초저유황 경유에 잘 용해되었으며 일정량(120 ppm)을 초저유황 경유에 첨가하여 HFRR 시험법으로 마모흔을 측정하여 윤활성능을 평가하였다. 그 결과, 첨가 전 초저유황 경유의 마모흔의 직경이 $552{\mu}m$에서 첨가 후 $300{\sim}05{\mu}m$으로 현저히 작아져 초저유황 경유의 윤활성능을 향상하는 것으로 확인되었다. 한편, 식물유의 종류에 따른 마모흔의 차이는 크지 않아 다이머산 유도체의 알킬기의 구조에 따른 윤활성능의 차이는 크게 나타나지 않았으나, 카르복실산 그룹을 함유하는 다이머산 유도체가 함유하지 않은 유도체보다 윤활성능이 우수하였다.

• 펄프종이기술
• /
• 제36권4호
• /
• pp.49-59
• /
• 2004

This study was carried out to obtain the basic data for producing higher functional coating agents for pulp mold by evaluating various kinds of starch derivatives. At that time, four kinds of starch derivatives were manufactured for making coating agents respectively. Physical properties of coated paperboards were tested. Conclusions obtained from this results were as follows. The water and oil resistance of hydroxypropylated, cyanoethylated and carboxymethy­lated starch were high when degree of molar substitution(DS) of propylene oxide, acrylonitrile and sodium monochloroacetate were 0.18, 0.07 and 0.009, respectively. Also, the those of crosslinked starch were high when degree of crosslinking of epichlorohydrin was 0.02. Consequently, $8\%$ solution of carboxymethylated starch made with DS 0.009 of monochloroacetate was the best among coating agents from starch derivatives men­tioned above.

• Toxicological Research
• /
• 제31권2호
• /
• pp.105-136
• /
• 2015

Polyethylene glycols (PEGs) are products of condensed ethylene oxide and water that can have various derivatives and functions. Since many PEG types are hydrophilic, they are favorably used as penetration enhancers, especially in topical dermatological preparations. PEGs, together with their typically nonionic derivatives, are broadly utilized in cosmetic products as surfactants, emulsifiers, cleansing agents, humectants, and skin conditioners. The compounds studied in this review include PEG/PPG-17/6 copolymer, PEG-20 glyceryl triisostearate, PEG-40 hydrogenated castor oil, and PEG-60 hydrogenated castor oil. Overall, much of the data available in this review are on PEGylated oils (PEG-40 and PEG-60 hydrogenated castor oils), which were recommended as safe for use in cosmetics up to 100% concentration. Currently, PEG-20 glyceryl triisostearate and PEGylated oils are considered safe for cosmetic use according to the results of relevant studies. Additionally, PEG/PPG-17/6 copolymer should be further studied to ensure its safety as a cosmetic ingredient.