• 한국연초학회지
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• 제29권2호
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• pp.80-84
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• 2007

This study was conducted to evaluate the prediction of sensory property of smoke from the leaf chemical property and characterize leaf chemical components for the best tobacco taste's leaves in burley tobacco. For analytical and sensory evaluations, sixteen grades were used. The major leaf chemical components to predict the sensory property of smoke were ether extract for tobacco-like, chloride for impact and total nitrogen/nicotine for irritation. Within ${\pm}20\;%$ range of difference, the predictable probabilities of sensory property of smoke from the leaf chemical properties were 100 % for tobacco-like, impact and irritation. As a result of K-means cluster analysis on the basis of tobacco taste, the desirable leaf chemical component contents were $6.5{\sim}6.8\;%$ in ether extract, $0.25{\sim}0.30\;%$ in chloride and $1.26{\sim}1.54$ in total nitrogen/nicotine ratio. This study suggest that the some regression equations may be useful to predict the sensory components of tobacco smoke from a few selected leaf chemical properties in burley tobacco and to select the burley tobacco leaves for enhance the tobacco taste of cigarette.

• 한국연초학회지
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• 제29권2호
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• pp.74-79
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• 2007

This study was conducted to evaluate the prediction of sensory property of smoke from leaf chemical property and characterize leaf chemical components for the best tobacco taste's leaves in flue-cured tobacco. For analytical and sensory evaluations, one hundred and forty grades were used. The major leaf chemical components to predict the sensory property of smoke were nicotine for impact, irritation and off taste & odor, and total sugar/nicotine ratio for tobacco taste. Within ${\pm}20%$ range of difference, the predictable probabilities of sensory property of smoke form leaf chemical property were 80.0% for off taste & odor and $91.4{\sim}96.4%$ for impact, irritation and tobacco taste. As a result of K-means cluster analysis on the basis of tobacco taste, the desirable leaf chemical component contents were $2.77{\sim}3.55%$ in nicotine and $5.1{\sim}6.9$ in total sugar/nicotine ratio. This study suggest that the some regression equations may be useful to predict the sensory property of tobacco smoke from a few selected leaf chemical components in flue-cured tobacco and to select the flue-cured tobacco leaves for enhance the tobacco taste of cigarette.

• 열처리공학회지
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• 제16권3호
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• pp.127-133
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• 2003

The effect of chemical composition on the microstructural change and tensile property in TRIP-assisted steels with different chemical composition was investigated by using SEM, TEM, XRD and UTM. As a result of microscopic observation, the morphology of retained austenite could be identified as two types; a granular type in a steel containing higher Si and a film type in a steel having higher C. For the case of higher C-containing steel with a tensile strength of 860 MPa and a total elongation of 38%, film-typed retained austenite could be observed between lath bainitic ferrite. Actually, metastable retained austenite was a requisite for the good formability, which means that chemical composition plays a significant role in the microstructure and tensile property of TRIP-assisted steels. With respect to tensile property, the steels containing suitable Si and Mn, respectively, showed a typical TRIP effect in stress-strain curve, while a steel containing higher Mn content exhibited the similar behavior shown in dual phase steel.

• 한국자동차공학회논문집
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• 제15권3호
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• pp.106-113
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• 2007

The effect of chemical composition on the microstructural change and tensile property in TRIP-assisted steels with different chemical composition was investigated by using SEM, TEM, XRD and UTM. As a result of microscopic observation, the morphology of retained austenite could be identified as two types : a granular type in a steel containing higher sillicon and a film type in a steel having higher carbon. For the case of higher carbon-containing steel with a tensile strength of 860 MPa and a total elongation of 38%, film-typed retained austenite could be observed between lath bainitic ferrite. Actually, metastable retained austenite was a requisite for the good formability, which means that chemical composition plays a significant role in the microstructure and tensile property of TRIP-assisted steels. With respect to tensile property, the steels containing suitable silicon and manganese, respectively, showed a typical TRIP effect in stress-strain curve, while a steel containing higher manganese content exhibited the assimilar behavior shown in dual phase steel.

• Composites Research
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• 제35권3호
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• pp.121-126
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• 2022

Owing to advantages of polymeric materials for hydrogen tank liner like light-weight property and high specific strength, polymer based composites have gained much attention. Despite of many benefits, polymeric materials for fuel cell tank cause problems which is critical to applications as low gas barrier property, and poor processability when adding fillers. For these reasons, improving gas barrier property of polymer composites is required to study for expanding application fields. This work presents impermeable polymer nanocomposites by introducing thin barrier coating using layer by layer (LBL) deposition method. Also, bi-layered and quad-layered nanocomposites were fabricated and compared for identifying relationship between deposition step and gas barrier property. Reduction in gas permeability was observed without interrupting mechanical property and processability. It is discussed that proper coating conditions were suggested when different coating materials and deposition steps were applied. We investigated morphology, gas barrier property and mechanical properties of fabricated nanocomposites by FE-SEM, Oxygen permeation analyzer, UTM, respectively. In addition, we revealed the mechanism of barrier performance of LBL coating using materials which have high aspect ratio.

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1278-1281
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• 2013

• 한국응용과학기술학회지
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• 제19권4호
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• pp.291-296
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• 2002

Fatty polyamide that gives softness, lubrication and bulky property and alkyl imidazoline that gives durable softness and antistatic property were synthesized. then, an O/W-type durable softener (DSN) was prepared by the emulsion of the synthesized fatty polyamide and alkyl imidazoline. Emulsion stability of the DSN was good, and the mixed HLB value was 11.2. From the measurement of softness, lubrication, antistatic property, bending resistance, and color fastness, it was proved that the prepared DSN was a good durable softener for nylon.

• 폴리머
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• 제32권4호
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• pp.397-402
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• 2008

과불소 에테르 화합물(PFPE)은 높은 접촉각 및 낮은 표면에너지, 우수한 윤활제 성질과 방오성의 특성을 가지고 있어 산업적으로 많은 관심을 받아왔다. 반면에, 합성단계의 복잡성과 위험성을 갖고 있어 많은 연구가 되어 오지 못했다. 본 연구에서는 과불소 폴리에테르 올리고머 형태의 새로운 실란화합물을 합성하고 $^{19}F$-NMR 및 $^1H$-NMR을 통하여 구조분석 하였다. 또한 코팅필름의 접촉각 및 흐름각, 내오염성 등 표면 특성을 조사하였다. 그 결과, 기존의 방오성 필름보다 낮은 흐름각과 우수한 내오염성의 특징을 보여 방오성 필름 코팅 제로서 산업적 가능성을 확인하였다.

• 대한화학회지
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• 제14권2호
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• pp.179-184
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• 1970

Four-ball EP and wear testers were used to study the effects of thickeners and additives on the EP and wear properties of some Korean greases. The EP property improved in the order of Li < Al < Ca, and the concentration of thickener did not affect the property when the same base oil and additives were used. The anti-wear property was improved in general when the additives were used.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1433-1436
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• 2009

Film morphology, crystallinity, and luminescence property of solution processed ZnO films have been studied. Fluorine addition and annealing ambient significantly change the defect-related emission band as well as the structural property. Using the overall emission behaviors, we can predict an optimized process condition for solution-based ZnO thin film.