• Journal of the Semiconductor & Display Technology
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• v.19 no.3
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• pp.36-42
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• 2020

Silver nanowire (AgNW) random-meshes with high transmittance, low sheet resistance, and high oxidation stability and flexibility were fabricated using solution-based processes. The random-mesh structure was obtained by forming bubbles whose sizes and densities were controlled using a corona treatment of polyethylene terephthalate (PET) substrates. To reduce the sheet resistance of the fabricated AgNW electrode, a washing process using ethanol solution was performed. In addition, nickel (Ni) was coated on AgNW to improve resistance to oxidation. The effects of corona treatment and Ni-coating on the transmittance, sheet resistance, oxidation stability, and flexibility of the AgNW electrodes were investigated.

• Tribology and Lubricants
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• v.29 no.6
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• pp.392-396
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• 2013

Biodiesel fuels contain unsaturated fatty acid ester, which can easily oxidize, especially when exposed to ultraviolet light. The products formed by this oxidation give rise to sediment or gum formation. As a result, the fuel can contribute to the corrosion and plugging of the filter pump. Antioxidants have been used in an effort to stabilize biodiesels, but there is still a need for a biodiesel composition with improved oxidation stability. In general, good fuel compositions should provide synergistic combinations of a biodiesel and antioxidants. Our work involved the synthesis of antioxidants to improve the oxidative stability of biodiesel fuel.

• Food Science of Animal Resources
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• v.39 no.5
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• pp.768-779
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• 2019

This study was performed to assess the comparison of the effects amongst butylated hydroxytoluene (BHT), clove extract (CE), and ascorbic acid (AA) as antioxidants on the oxidative stability and color values in fresh beef patties. The adding of BHT, AA, and CE to patties significantly restrained lipid oxidation, lowered hue angle as color value, and expanded redness and chroma values of fresh beef patties in comparison to the control (p<0.05). BHT and AA significantly led to impede the protein oxidation of patties by lowering carbonyl content (p<0.05). CE had no negative effect on protein oxidation. The antioxidant effects of BHT, AA, and CE were obviously manifested. Nonetheless, BHT, AA, and CE appeared to have insignificant difference of each other for lowering the protein oxidation at the end of storage. BHT and CE represented lowered lipid oxidation in comparison to AA. The antioxidant effects of BHT, AA, and CE on lipid oxidation were more marked than the effects on protein oxidation. Furthermore, CE as a natural antioxidant evinced the efficiency in oxidative stability and color stability in fresh beef patties. The study implied that CE could substitute the use of BHT and AA when making beef patties during storage.

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.2
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• pp.47-52
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• 2014

Oxidation stability and cold fuid property are considered as the most important factors for determining biodiesel quality. Among the fatty acids, monounsaturated fatty acid satisfy both oxidation stability and cold flow property of biodiesel quality standards. Microalgae with high monounsaturated fatty acid contents is have some benefit for producing to produce biodiesels with satisfying quality standards. In this study, monounsaturated fatty acid contents of a isolated microalga from Youngheung island was analyzed. Phaeodactylum tricornutum was isolated by streaking, and growth rate and fatty acid composition of the algae were investigated. Total FAME contents were consisted of 26% of saturated fatty acids, 43% of monounsaturated fatty acids, and 18% of polyunsaturated fatty acids. The contents of monounsaturated fatty acid were especially high in the Phaeodactylum species. This result implies that the FAMEs from P. tricornutum may contribute to improve the oxidation stability and cold flow property of biodiesel.

• Tribology and Lubricants
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• v.12 no.1
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• pp.36-41
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• 1996

The suitability of a pressure differential scanning calorimetry (PDSC) in monitoring the quality of synthetic base fluids has been investigated using polyalphaolefin (PAO) oils as an example. Induction period meassured at 170, 180 and 19$0^{\circ}C$, and 3.53 MPa oxygen pressure was applied to characterize their oxidation stability. The PDSC method has proven to be simple and repeatable and requires only small sample size for testing. More importantly, it can be applied in differentiating the oxidation performance quality of PAO oils and is versatile enough for use in studying kinetic aspects of PAO oil oxidation which include the effect of temperature and antioxidant concentration. Additionally, the method appears to correlate well with a rotary bomb oxidation test (RBOT).

• Journal of Marine Bioscience and Biotechnology
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• v.7 no.1
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• pp.1-10
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• 2015

Bio diesel has advantages to reduce GHG(Greenhouse Gas) compare with the fossil fuel by using oil comes from plant/animal sources and even waste such as used cook oil. The diversity of energy feeds brings the positive effects to secure the national energy mix. In this circumstance, micro-algae is one of the prospective source, though some technical barriers. We analyzed the bio diesel which was derived from Dunaliella tertiolecta LB999 through the BD100 quality specifications designated by the law. From that result, it is revealed that the oxidation stability is one of the properties to be improved. In order to find the reason for low oxidation stability, we analyzed the oxidation tendency of each FAME components through some methods(EN 14111, EN14112, EN16091). In this study, we could find the higher double bond FAME portion, the more oxidative property(C18:1${\ll}C18:3$) in bio diesel and main unsaturated FAME group is acted as the key component deciding the bio diesel's oxidation stability. It is proved experimentally that C18:3 FAME are oxidized easily under the modified accelerated oxidation test. We also figure out low molecular weight hydrocarbon and FAME were founded as a result of thermal degradation. Some alcohol and aldehydes were also made by FAME oxidation. In conclusion, it is necessary to find the way to improve the micro-algal bio diesel's oxidation stability.

• Journal of the Korean Applied Science and Technology
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• v.32 no.4
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• pp.639-648
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• 2015

Some materials of fatty acids in the biodiesel affect the physical/chemical properties like density, kinematic viscosity, total acid number and oxidation stability by forming an organic fatty acid in combination with oxygen in the air. To solve the problem of the oxidative stability of biodiesel, various kinds of antioxidant has added and analyze the characteristics of the physical/chemical property changes by the addition of antioxidant. Oxidation stability increased by the increase of additives content. The TBHQ among the seven kinds of the additives showed the best performance. Also, 4 kinds of additives like propyl gallate, butyl-amine and pyrogallo has showed above 10 hr of oxidation stability at the addition of 500 ppm. In case of pyrogallo, this is not appropriate as an additive to suitable quality standards of total acid number. TBHA, DTBHQ of hydroquinone was satisfied with the quality standard of oxidation stability but the target of this research(above 10 hr) did not satisfied with oxidation stability. Propyl gallate is also a suitable at the quality standards of total acid number but it was shown not to be an appropriate to the additives due to increasing the total acid number by increasing of the content of additives at the addition of 500 ppm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.11
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• pp.1149-1155
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• 2004

In this paper, novel methods for improvement of thermal stability of Ni-germano Silicide were proposed for nano CMOS applications. It was shown that there happened agglomeration and abnormal oxidation in case of Ni-germano Silicide using Ni only structure. Therefore, 4 kinds of tri-layer structure, such as, Ti/Ni/TiN, Ni/Ti/TiN, Co/Ni/TiN and Ni/Co/TiN were proposed utilizing Co and Ti interlayer to improve thermal stability of Ni-germano Silicide. Ti/Ni/TiN structure showed the best improvement of thermal stability and suppression of abnormal oxidation although all kinds of structures showed improvement of sheet resistance. That is, Ti/Ni/TiN structure showed only 11 ohm/sq. in spite of 600 $^{\circ}C$, 30 min post silicidation annealing while Ni-only structure show 42 ohm/sq. Therefore, Ti/Ni/TiN structure is highly promising for nano-scale CMOS technology.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.359-360
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• 2002

A methodology was developed for evaluation of oxidation stability of base stocks and engine oils. Analytical procedures for both classes of lubricants were based on the ASTM standards D 6186 and/or E 2009. The procedures were applied to a set of engine oils of the SAE 5W-30 specification, and to a set of several hydrocracked and solvent neutral base oils, both with and without addition of antioxidant. A potential of a pressure DSC for diagnostic purposed was also demonstrated by monitoring the engine oil ageing during its operation in heavy-duty engine.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.145-149
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• 2005

This study was carried out to investigate the effect of dietary RVS on the WHC, color stability, and lipid oxidation of Hanwoo (Korean cattle) beef during cold storage after thawing, RVS fed Hanwoo (Korean cattle) beef was more effective in increasing WHC, color stability and delaying lipid oxidation than that without RVS in diet. And 4% RVS fed Hanwoo (Korean cattle) beef showed the greatest effects.