• Composites Research
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• v.28 no.6
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• pp.395-401
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• 2015

This study investigated the thermal stability of Grubbs' catalyst and its reactivity with self-healing agents for self-healing damage repair. Four types of Grubbs' catalyst supplied by manufacturers were considered and each catalyst was tested in as-received and grinded conditions. Four types of self-healing agents were prepared by varying the mixing ratio of dicyclopentadiene (DCPD) and 5-ethylidene-2-norbonene (ENB). Heat flows as a function of temperature were measured through a differential scanning calorimetry (DSC) to determine the thermal stability of catalysts. Reaction heats of self-healing agents with the catalyst were measured to evaluate the reactivity of the catalyst. For this evaluation, Fluka Chemika Grubbs' catalyst was used based on the maximum temperature and the time to reach the maximum temperature. According to the results, catalysts had different shapes depending on the manufacturer and the results showed that the smaller the size of the catalyst the higher the reactivity with self-healing agents. As the ENB ratio in self-healing agents increased, the maximum temperature increased, and the time to reach the maximum temperature decreased. As the amount of the catalyst increased, the maximum temperature increased, and the time to reach the maximum temperature decreased. Considering the thermal stability of the catalyst and its reactivity with the self-healing agent, combination of 0.5 wt% catalyst and the D3E1 self-healing agent was optimal for self-healing damage repair. Finally, as the thermal decomposition may occur depending on the environmental temperature, the catalyst must not be exposed to temperature higher than that is necessary to maintain the thermal stability of the catalyst.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.74.1-74.1
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• 2010

단결정 실리콘 태양전지 공정에서 이방성 습식 식각 용액을 이용하여 기판 표면에 피라미드 구조를 형성하는 것을 텍스쳐링이라고 한다. 실리콘 기판의 표면을 식각하여 요철구조를 만들어줌으로써 셀 내부로 입사되는 광량을 증가시켜 태양전지의 단락 전류 및 효율 향상 효과를 얻을 수 있다. 일반적인 태양전지 공정에서는 요철구조를 형성할 시 따로 마스크를 사용하지 않으며, 태양전지 급 웨이퍼를 절삭손상층 식각 한 후, 강염기성 용액과 알코올의 혼합용액에 담가서 이방성 식각을 실시하여 요철 구조를 형성한다. 본 연구는 기존의 텍스쳐링 공정에서 사용되는 대표적인 용액인 수산화칼륨(potassium hydroxide, KOH)과 알코올의 혼합용액과 사메틸수산화암모늄(Tetramethylammonium Hydroxide, TMAH)과 알코올의 혼합용액에 Triton X-100 계면활성제를 각각 첨가하여 실험을 진행하였다. 식각된 태양전지용 실리콘 기판의 표면은 주사전자현미경(Scanning Electron Microscope)을 통하여 관찰하였고, 분광광도계(UV/VIS/NIR Spectrophotometer)로 반사도 값을 측정하여 기판의 특성을 평가하였다.

• Analytical Science and Technology
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• v.11 no.6
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• pp.413-420
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• 1998

The hydrophobic interaction has been studied on sodium naphthalene derivatives such as sodium 1-naphthaleneacetate (S1NA), sodium 1-naphthalenemalonate (SINM), sodium 2-naphthaleneacetate (S2NA), and sodium 2-naphthalenepropionate (S2NP) in $H_2O$-MeOH mixture solutions and in surfactant solutions. In $H_2O$-MeOH mixture solutions, the hydrophobic interaction was measured, and resulted in the red shift in emission spectra. In cationic surfactant, cetyltrimethylamonium bromide (CTAB) solution, the hydrophobic interaction was also observed by the red shift in absorption and emission spectra.

• Korean Journal of Poultry Science
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• v.17 no.2
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• pp.123-126
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• 1990

Antioxidant activity of ginseng was studied in a chicken model system containing sodium nitrite, sorbic acid and ascorbate with or without ginseng. Results obtained are as follows. 1. The antioxidant effect of ginseng increased with increasing concentration but the increment decreased with increasing concentration. 2. In the sample containing sodium nitrite, sorbic acid and ascorbate, the addition of ginseng enhanced the antioxidant effect. Treatment with ginseng, nitrite, sorbic acid and asrorbate( G-NaSoAs) showed the highest antioxidant activity whereas that with nitrite and sorbic acid(NaSo) did the lowest.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.48-55
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• 2011

It was found that the absorbent mixed with 2-aminoethanol and others has been applied to remove them via chemical neutralization. The absorbent of natural second metabolites was achieved by a removal efficiency of 20~30% by itself depending on treatment conditions, but the complex absorbent mixed with 0.2% amine chemical provides the removal efficiency of over 98%. Optimal removal efficiencies have been examined against two major parameters of the temperature and pH to remove ammonia and hydrogen sulfide gases. The chemical analysis was also performed to analyze the composition of an essential oil by GC-MS. The monoterpenes in an essential oil reacted with odorous compounds by neutralization and their reaction mechanism was partially elucidated.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.164-168
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• 1985

In order to enhance herbicidal efficacy of amide and diazine herbicides, synergistic effects of pretilachlor and pyrazoxyfene or butachlor and pyrazolate on control of Cyperus serotinus were determined by isobole method. Interaction indices(I) between pretilachlor and pyrazoxyfene treated at 0 and 3rd leaf stage were 2.64 and 2.07 and hence showed synergistic effect for control of Cyperus serotinus. The points indicated Imax between pretilachlor and pyrazoxyfene were 0.7:1.3 g ai/a and 9.0:20.5 g ai/a at 0 and 3rd leaf stage, respectively. Combination of butachlor and pyrazolate showed synergistic effect(1=1.57) on control of Cyperus serorinus and point indicated Imax was 48.0:20.9 g ai/a.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.31-38
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• 2003

It has been recently reported that the presence of sulphate causes abnormal volume changes in lime-stabilized soils. Volume changes in lime-stabilized soils can take place due to sulphate compounds such as ettringite. Sulphate compounds caused a variety of serious geotechnical hazards such as swelling pressure and damages to light structures and pavements. This paper discusses the influence of sulphate on the soil specimens treated with quicklime and chemical additives. The physical and mechanical characteristics were studied by means of laboratory tests. The results showed that the presence of sulphate treated soil reduced the shear strength of the lime treated soils and increased the swelling properties. SEM and XRD results indicated that the presence of sulphate producted needle-like crystals such as ettringite. Moreover, the role of needle-like crystals in specimen was probably related to the swelling properties.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.7 no.5
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• pp.39-46
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• 1986

''2종 또는 그 이상의 작용특성이 상이한 약제의 혼합제제는 작물의 재배기간중 동시에 발생하는 병해충을 효율적으로 방제할 수 있고 저항성해충에 대한 안전방제, 방제시기 일실에 의한 피해의 최소화가 가능하며 살포회수를 줄여 노동력을 절감할 수 있고 단위면적당 살포주성분량 절감으로 농약가격을 낮출수 있다 ''

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.32 no.11
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• pp.26-31
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• 2003

가스터빈/연료전지 혼합형 발전시스템은 고온형 연료전지 발전시스템의 산화제(공기) 공급부가 마이크로터빈으로 대체되어 고온고압의 공기가 연료전지로 공급되고 연료전지의 반응가스가 터빈을 구동하여 두 시스템이 동시에 서로 다른 방식으로 전력을 생산하는 시스템을 의미한다.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.46-46
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• 2017