• 대한기계학회논문집B
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• 제24권7호
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• pp.938-944
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• 2000

Recently, micro fin tube is widely used to heat exchanger for high performance. And, as the alternative refrigerants for R-22, hydrocarbons such as R-290, R-600 and R-600a are very promising because of their low GWP and ODP. Thus, R-290 was used as working fluid in this study. Most design of heat exchanger had been based on heat transfer characteristics of pure refrigerant although refrigerant oil exists in the refrigeration cycles. So, the influence of oil on heat transfer characteristics have to be considered for investigating exact evaporation heat transfer characteristics. But, this is an unresolved problem of refrigeration heat transfer. Therefore the influence of the refrigeration oil to the evaporation heat transfer characteristics of R-290 were conducted in a horizontal micro tin tube. The mineral oil was used as refrigeration oil. The experimental apparatus consisted of a basic refrigeration cycle and a system for oil concentration measurement. Test conditions are as the follows; evaporation temperature $5^{\circ}C$, mass velocity 100 $kg/m^2s$, heat flux 10 $kW/m^2$, oil concentration 0, 1.3, 3.3, 5.7 wt.%, and quality $0.07{\sim}1.0$. When refrigeration oil was entered, oil foaming was observed at the low quality region. And, very small bubbles were observed as quality was increased. Pressure drop and heat transfer coefficient increased as the concentration of refrigeration oil increased to 5 wt.%.. The performance index of heat exchanger was the highest near 3.3 wt.%.

• 대한화장품학회지
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• 제25권4호
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• pp.17-41
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• 1999

Manuka oil sometime named New Zealand's tea tree oil is soluble in oil and come from nature. The $\alpha$-pinene extracted from Manuka oil and R-limonene which is one of the component of extracted Citrex from Grapefruit were used to estimate the antimicrobial activity and to improve the capability of antiseptic. Disk diffusion and broth dilution methods were used to measure the antimicrobial activity. Escherichia coli which is gram-negative bacteria and Staphylococcus aureus which is gram-positive bacteria were used as strain. The antimicrobial activity of Manuka oil and $\alpha$-pinene for Escherichia coli, Staphylococcus aureus is similar when the concentration of Manuka oil and $\alpha$-pinene is $10{\mu}l$. However, Antimicrobial activity of Manuka oil for Escherichia coli, Staphylococcus aureus is better than that of $\alpha$-pinene when the concentration of Manuka oil and $\alpha$-pinene is low. Antimicrobial activity of Citrex is superior to that of R-limonene. The proper ratio of Maunka oil and Citrex can improve the antimicrobial activity. The proper ratio obtained from studies was 75% of Maunka oil and 25% Citrex for Escherichia coli, 25% of Maunka oil and 75% Citrex for Staphylococcus aureus.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 1999년도 IFSCC . ASCS 학술대회 발표 논문
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• pp.17-41
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• 1999

Manuka oil sometime named New Zealand's tea tree oil is soluble in oil and come from nature. The $\alpha$-pinene extracted from Manuka oil and R-limonene which is one of the component of extracted Citrex from Grapefruit were used to estimate the antimicrobial activity and to improve the capability of antiseptic. Disk diffusion and broth dilution methods were used to measure the antimicrobial activity Escherichia coli which is gram-negative bacteria and Staphylococcus aureus which is gram-positive bacteria were used as strain. The antimicrobial activity of Manuka oil and $\alpha$-pinene for Escherichia coli, Staphylococcus aureus is similar when the concentration of Manuka oil and $\alpha$-pinene is 10${mu}ell$. However, Antimicrobial activity of Manuka oil for EscherEchta coli, Staphylococcus aureus is better than that of $\alpha$-pinene when the concentration of Manuka oil and $\alpha$-pinene is low. Antimicrobial activity of Citrex is superior to that of R-limonene. The proper ratio of Maunka oil and Citrex can Improve the antimicrobial activity. The proper ratio obtained from studies was 75% of Maunka oil and 25% Citrex for Escherichia coli, 25% of Maunka oil and 75% Citrex for Staphylococcus aureus.

• Ocean and Polar Research
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• 제39권1호
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• pp.1-11
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• 2017

The aim of this study was to determine the physiological response and the applicable concentration ranges of anesthetic clove oil and anesthetic lidocaine-HCl, and to investigate the synergistic effect of a mixture of these two anesthetics on the in grass puffer (Takifugu niphobles). The anesthesia times decreased and the recovery times increased with increasing concentrations of clove oil and lidocaine-HCl. Applicable concentration ranges for long-term transportation requiring more than 1 hour were 2 ppm for clove oil and 50 ppm for lidocaine-HCl. With mixtures of the two anesthetics, the anesthesia time decreased as the admixture concentration of clove oil and lidocaine-HCl increased. Anesthesia times of experimental groups with the combined anesthetics were shorter than those with the same concentrations of clove oil or lidocaine-HCl alone. Plasma cortisol concentrations were highest at 6 hours in all experimental groups anesthetized with the mixture of clove oil and lidocaine-HCl, while all groups with clove oil or lidocaine-HCl alone had the highest plasma cortisol concentrations at 12 hours. Plasma glucose concentrations were highest at 12 hours in experimental groups anesthetized with the mixture of clove oil and lidocaine-HCl, while groups with clove oil or lidocaine-HCl alone had the highest plasma glucose at 24 hours. The results of this study provide basic information about anesthetics and the synergistic effect of mixtures of anesthetics in this fish species. This information should be useful for aquaculturists who require methods for safe and easy fish handling, and for transporters who require that minimal stress is imposed on fish during transport.

• 한국지반환경공학회 논문집
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• 제11권10호
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• pp.49-55
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• 2010

에너지원 및 다양한 화학제품의 원료로 유류의 소비량이 증가함에 따라 유류의 유출사고가 빈번하게 발생하고 있다. 유류오염 지하수 처리를 위해 용존공기부상법이 사용되어지고 있으나 용해성 기름을 효과적으로 제거하지 못하고 있는 실정이다. 따라서 지하수내 주오염원인 자유상 유류와 친수성(oil-in water) 또는 친유성 에멜젼(water-in oil) 상태의 기름과 용해성 기름을 효과적으로 저감하는 것이 필요하다. 본 연구에서는 용존공기부상법에 펜톤 산화 공법을 사용하여 효과적인 유류 오염 지하수 처리를 연구하였다. 펜톤 실험 결과 TPH(Total Petroleum Hydrocarbon) 제거를 위한 최적 조건은 pH 3, $H_2O_2$ 주입농도 25mM과 $Fe^{2+}$ 주입농도 25mM으로 나타났다. DAF와 펜톤 산화 실험을 수행한 결과 7분내에 TPH(Total Petroleum Hydrocarbon)와 COD(Chemical Oxygen Demand) 농도가 각각 1.5mg/L와 40.0mg/L 이하로 감소하는 것으로 나타났다. 하지만 펜톤 산화 반응으로 인하여 슬러지 농도가 약 5배 가량 증가하여 후단에 침전조를 설치하는 것이 바람직하다.

• Journal of Nutrition and Health
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• 제29권2호
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• pp.177-187
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• 1996

We studied the effects of fish oil supplementation with low does on the lipid concentration and fatty acid of plasma and the fatty acid composition of plasma phospholipid and erythrocyte of lactating women. The subjects, 18 lactating women, who were exclusively breast-fed their babies were classifed into a control group and 2 fish oil groups according to dose; the subjects of fish oil groups were supplemented with 1.96g/d or 3.92g/d of fish oil, respectively for 2 weeks from 10 to 12 weeks postpartum. All subjects consumed their usual diet at home. Blood sample were collected at the final day of experiment. The plasma HDL-cholesterol level increased significantly by fish oil supplementation. The concentrations of DHA (docesahexaenoic acid) and EPA (eicosapentaenoic acid) in the plasma PC(phosphatidylcholine) and PE (phosphatidylethanolamine)of fish oil groups tended to increase, but not significant. However, the concentrations of DHA and EPA of PC and PE in erythrocyte were not affected by fish oil supplementation. These results demonstrate that fish oil supplementation with low dose does not change the concentration of plasma lipid as well as fatty acid composition in plasma PC and PE and red blood cell obviously. However the increase of plasma HDL-cholesterol level, the reduction of atherogenic index(AI) and the tendency of increase of DHA and EPA concentrations in plasma PC and PE indicate that there may be some beneficial effects on maternal lipid metabolism if fish oil intakes were increased.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.201-204
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• 2012

Combustion characteristics of boiler fuels made of bio-oil and light-oil were experimentally investigated. Bio-oil was obtained by fast pyrolysis of woody biomass. Emulsion fuel made by mixing bio-oil (up to 30wt%) with light-oil and surfactant was completely burnt, resulting in the formation of combusted gas containing CO concentration less than 10ppm. Simple mixtures of bio-oil and light-oil with separate delivery lines also gave nice combustion characteristics.

• 설비공학논문집
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• 제12권2호
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• pp.209-217
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• 2000

The solubility and miscibility measurement apparatus was developed and used to obtain data for refrigerant/oil mixture. The solubility and miscibility data for R-410A/68 ISO VG polyol ester (POE) oil mixture are obtained over the temperature range from -20 to $60^{circ}C\;with\;10^{\circ}C$ intervals and the oil concentration range from 0 to 90 wt%. Using the experimental data, an empirical model was developed to predict the solubility relations for R-410A/POE oil mixture at equilibrium. In the R-410A/Solest 68 oil mixture, the average root-mean-square deviation between measured data and calculated results from the empirical model is 3.4% and in the R-4104/EMKARATE RL 68H oil mixture, that is 2.86%. For R-410A/68 ISO VG POE oil mixture immiscibility was usually observed at the low oil concentrations(5~30 wt%) over the all experimental temperature range($-20~60^{circ}C$) and at the high oil concentrations(50~90 wt%) over the low experimental temperature range($-2O~0^{circ}C$).

• 한국식품영양과학회지
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• 제18권3호
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• pp.338-347
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• 1989

${\omega}-3$계와 ${\omega}-6$계 PUFA가 혈청과 간장의 지질대사에 미치는 영향을 규명하기 위하여 ${\omega}-6$계 linoleic acid를 약 64% 함유하고 있는 고추종자기름과 ${\omega}-3$계 linolenic acid 함유비율이 약 60%인 들깨기름을 몇가지 비율로 혼합하여 흰쥐에게 급여하여 얻어진 결과는 다음과 같다. 혈청중 총 cholesterol 농도는 들깨기름 10%를 급여받은 1군이 고추씨기름의 함량이 높은 4군과 5군에 비하여 유의적으로 낮았으며, HDL-cholesterol 농도는 ${\omega}-6$계 linoleic acid의 비율이 높아짐에 따라 점차로 증가하는 경향이었고 ${\omega}-3$계 linolenic acid 함유율이 높아짐에 따라 유의성있게 저하하는 경향이었다. 총 cholesterol에 대한 HDL-cholesterol 농도는 10% 고추종자기름을 급여한 5군에서 가장 높았고 5% 들깨유와 5% 고추종자기름을 혼합 급여한 3군의 순이었다. 혈청중의 중성지질과 인지질 농도는 7.5% 들깨기름과 2.5% 고추종자기름의 혼합 식이군인 2군이 2.5% 들깨유와 7.5% 고추종자유 혼합 식이군인 4군에 비하여 유의적으로 낮았다. 간장중의 총 cholesterol 농도는 고추씨 기름 10% 단독 식이군에서 가장 높았으며 들깨유와 고추씨 기름의 혼합 식이군 (2, 3, 4 군)에서 낮았다. 간장중의 중성지방 농도는 10% 들깨유군 및 10% 고추씨기름의 단독 식이군에서 높은 반면 혼합 투여군에서 감소하는 경향을 보였으며 인지질 농도는 각 군간에 유의적인 차이는 없었다.

• 통합자연과학논문집
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• 제1권1호
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• pp.41-46
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• 2008

The aim of this study is to evaluate the effects essential oil from Lavendular officinalis on the production of UVB-irradiated-induced nitric oxide(NO), in vivo and in vitro. NO is a recently discovered mediator of cell communication involved in a variety of physiological and pathophysiological processes. This enzyme is present in various tissues including smooth muscle cells and macrophages and take part in several immunopathological process. In vitro, the cytotoxicity and cell viability of aroma oil was evaluated by the MTT assay in the concentration of 0.01, 0.05, 0.1%. And, the effect of aroma oil was investigated to production of NO in human fibroblast cells line CCD-986sk ($2{\times}10^5$ cell/well) after UVB-irradiation with aroma oil (0.01, 0.1, and 1%). The result showed that aroma oil did not affected the production of NO. In vivo, it was investigated to production of NO after UVB- irradiation with aroma oil. The experimental groups were divided into four groups. Aroma oil was stimulated the production of NO by itself. As the results, all of the in vitro and in vivo, aroma oil were affected production of NO by dependent the concentration-manners.