• Fibers and Polymers
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• 제4권1호
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• pp.20-26
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• 2003

The thermal behavior, morphology, ester-interchange reaction of Poly(trimethylene terephthalate) (PTT)/poly(ethylene terephthalate) (PET) melt blends were investigated over the whole composition range(xPTT/(1-x)PET) using a twinscrew Brabender. The melt blends were analyzed by differential scanning calorimetry (DSC), nuclear magnetic resonance spectroscopy ($^{13}{C-NMR}$), and scanning electron microscopy (SEM). Single glass transition temperature ($T_g$) and cold crystallization temperature ($T_cc$) were observed in all melt blends. Melt blends were found to be due to the ester-interchange reaction in PTT/PET blend. Also the randomness of copolymer increases because transesterification between PT and PET increases with increasing blending time This reaction increases homogeneity of the blends and decreases the degree of crystallinity of the melt blends. In PTT-rich blends, mechanical properties decrease with increase of PET content compared with that of pure PTT. And, in PET-rich blends, tensile modulus decreases with increase of PTT content, but tensile strength and elongation is similar to that of pure PET.

• International Journal of Automotive Technology
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• 제6권1호
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• pp.15-21
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• 2005

The purpose of this paper is to experimentally investigate the engine pollutant emissions and combustion characteristics of diesel engine fueled with ethanol-diesel blended fuel (bio-diesohol). The experiments were performed on a single-cylinder DI diesel engine. Two blend fuels were consisted of $15\%$ ethanol, $83.5\%$ diesel and $1.5\%$ solublizer (by volume) were evaluated: one without cetane improver (E15-D) and one with a cetane improver (E15-D+CN improver). The engine performance parameters and emissions including fuel consumption, exhaust temperature, lubricating oil temperature, Bosch smoke number, CO, NOx, and THC were measured, and compared to the baseline diesel fuel. In order to gain insight into the combustion characteristics of bio-diesohol blends, the engine combustion processes for blended fuels and diesel fuel were observed using an Engine Video System (AVL 513). The results showed that the brake specific fuel consumption (BSFC) increased at overall engine operating conditions, but it is worth noting that the brake thermal efficiency (BTE) increased by up to $1-2.3\%$ with two blends when compared to diesel fuel. It is found that the engine fueled with ethanol-diesel blend fuels has higher emissions of THC, lower emissions of CO, NOx, and smoke. And the results also indicated that the cetane improver has positive effects on CO and NOx emissions, but negative effect on THC emission. Based on engine combustion visualization, it is found that ignition delay increased, combustion duration and the luminosity of flame decreased for the diesohol blends. The combustion is improved when the CN improver was added to the blend fuel.

• 대한기계학회논문집B
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• 제27권2호
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• pp.181-187
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• 2003

Biodiesel fuel as an alternative fuel for diesel engine has a great possibility to solve the problems such as air pollution. It is a domestically produced, renewable fuel that can be manufactured from vegetable oils, used vegetable oils, or animal fats. In this study, the usability of biodiesel fuel derived from rice bran oil as an alternative fuel for diesel engines was investigated in agricultural diesel engine. Emissions were characterized with neat biodiesel fuel and with a blend of biodiesel fuel and conventional diesel fuel. Since the biodiesel fuel includes oxygen of about 11%, it could influence the combustion process strongly. So, the use of biodiesel fuel resulted in lower emissions of carbon monoxide, carbon dioxide, and smoke emissions without any increase of oxides of nitrogen. It is concluded that biodiesel fuel can be utilized effectively as a renewable and an environmentally Innocuous fuel for diesel engine.

• 한국의류학회지
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• 제31권7호
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• pp.1119-1127
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• 2007

Nonwovens have been widely used in various regions from the households to the industrial, agricultural and medical goods. Synthetic fibers have been used for source of nonwovens commonly because of their useful and economic properties. They are not only main factor causing environmental problems but also spend huge cost to renew the environmental disruption by them. Nonwovens must have both cost-competitiveness and environment-friendly property to be the desirable sources in 21th centuries. For meet these needs, it is suitable for the times that economical and environmentally-safe kenaf fibers would be used as raw materials of nonwovens. Kenaf and polyester fibers were blended in 4 types of ratio : 0/100, 20/80, 40/60, 60/40 were needle-punched. The nonwovens properties such as color values, surface appearance, strength, elongations, stiffness, moisture regain, water and oil absorbency, and electrification were tested. As the results, tensile and tear strengths, water and oil absorbency were maximum at 20/80 kenaf/polyester blend nonwoven, because of effecting by nonwoven structure and fiber properties. The moisture regain were increased according to kenaf were blended and the eletrification reduced in proportion to the kenaf fibers by chemical property of fiber composed nonwovens.

• 한국염색가공학회지
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• 제35권4호
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• pp.231-238
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• 2023

Microporous gel films of 29 m were prepared by the gel drawing of UHMWPE/soybean oil blend (4:6, w/w) up to 800%. The stretched films containing the optimal photoinitiator concentration, depending on the film thickness, was cross-linked under 365 nm LED-UV irradiation and the oil was extracted with n-hexane, resulting in a gel fraction of 95 % or more. With the formation of the cross-linked structure, the melt-down temperature and melt-down elongation increased by 16 ℃ and by 63% respectively. Also the thermal stability of the crosslinked UHMWPE was proved by the area shrinkage under the heat treatment decreased to 3.8 % compared to 17.4 % for the pristine film, and by the reductions in the combustion heat. The enhanced thermal stability of the crosslinked UHMWPE microporous membranes can be used for various industrial applications such as filters, electric vehicles and energy storage systems.

• 디지털융복합연구
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• 제14권8호
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• pp.547-553
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• 2016

본 연구에서는 피부상재균을 대상으로 단일오일의 항균효과를 살펴보는 동시에 2가지 이상의 오일을 혼합한 블랜딩 오일이 실제로 상승효과를 일으키는지 탐색해보고자 하였다. 항균실험에 사용된 에센셜 오일은 100% 유칼립투스(EU), 레몬(LE), 라벤더(LA) 오일이었으며, 2가지 오일 블랜딩의 상승효과를 알아보기 위하여 EU+LE, LE+LA, EU+LA을 1:1의 비율로, 3가지 오일 블랜딩의 상승효과를 알아보기 위해 각 오일을 1:1:1 비율로 혼합하여 배지의 표피포도상구균에 적용한 후 항균 영역 값을 평균 비교하였다. 그 결과, 단일오일에서는 LE이 가장 높은 항균력을 보였으며, LA는 가장 낮은 항균력을 보였다. 2가지오일 블랜딩에서는 EU+LA의 항균력이 단일오일의 항균력의 합보다 커 상승효과를 나타내었다. 그러나 3가지 오일 블랜딩의 항균효과는 아주 낮게 나타나 상승효과를 나타내지 않았다. 이러한 결과는 블랜딩 한 오일의 수 보다 오일을 구성하는 화학 성분들 간의 상호작용이 상승효과에 더욱 중요한 영향을 미친다는 것을 보여주었다. 따라서, 본 연구를 토대로 에센셜 오일 블랜딩에 대한 과학적 증거 마련이 더욱 필요할 것이라 사료된다.

• 동력기계공학회지
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• 제13권6호
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• pp.51-56
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• 2009

Recently, lots of researchers have been attracted to develop various alternative fuels in diesel engine. The use of biodiesel fuel(BDF) is an effective way of substituting diesel fuel in the long run. But biodiesel fuel can affect the performance and emissions in diesel engine because it has different chemical and physical properties from diesel fuel. In this study, to investigate the combustion characteristics of biodiesel fuel as an alternative fuel for D.I. diesel engine, experiments were carried out at the three-cylinder, four stroke D.I. diesel engine with T/C. As a result, shorter ignition delays were observed for the biodiesel blend cases relative to the diesel oil. The pick value of premixed combustion for the rate of heat release is increased with decreasing C.F.W. temperature.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.602-605
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• 2007

Soybean and rape seed are common feedstocks for biodiesel product ion in USA and Europe, respectively. On the other hand, South Eastern countries like Malaysia and Indonesia have surplus palm crops. However due to substantial amount of saturated fats in palm, the palm biodiesel has poor low temperature properties. To improve the low temperature flow properties as biodiesel, the dependence of the cold filter plugging point (CFPP) on the fatty acid compositions was examined. Two different kinds of biodiesels, palm and soybean biodiesels, were blended with the different volume ratios. And the low temperature flow properties of 0.5%, 1%, and 5% biodiesel in diesel blend fuels was tested. The decrease of CFPP was not observed for BD1 with Palm BD. Also, WDI test didn't exceed in the range of 4oC by the mixing of Palm BD upto 5% in commercial diesels.

• Journal of Pharmaceutical Investigation
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• 제39권1호
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• pp.13-18
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• 2009

Docetaxel is an anticancer agent with low aqueous solubility. More extensive clinical use of this drug is somewhat delayed due to lack of appropriate delivery vehicles. An attempt was made to adopt an o/w emulsion as the drug carrier which incorporated docetaxel in the propyleneglycerol stabilized by a mixed-emulsifier system. A suitable formulation was found in this study: 10 mg/mL docetaxel, 10% (w/v) oil blend, 4% (w/v) PG, 3% (w/v) Solutol HS 15 in 2.25% (w/v) glycerol solution. The formulated emulsion has very good stability when stored at $40^{\cird}C$, and the docetaxel containment efficiency can be maintained above 95% and the mean emulsion diameter around $10{\mu}m$ for at least 3 months. The formulated emulsion is a promising carrier for docetaxel and other lipophilic drugs.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.269-270
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• 2003

Thermoplastic polyurethane is a engineering plastic with elasticity, abrasion resistance and good resistance to oil, grease and many solvents. Characteristics of poly(vinyl chloride) (PVC) are good general chemical resistance, excellent weatherablility, good insulate. properties, and self-extinguishing or flame resistance, etc. So it is used in widespread industrial fields[2]. (omitted)