• 한국고분자학회지:고분자과학과기술
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• 제25권6호
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• pp.493-497
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• 2014

• 한국환경농학회지
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• 제10권2호
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• pp.133-137
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• 1991

Fly ash가 토양(土壤)의 화학성(化學性) 및 물리성(物理性)에 미치는 영향(影響)을 규명(糾明)하기 위하여 Fly ash를 증류수(蒸溜水) 및 0.5N-acetic acia로 추출하여 각종 무기성분(無機成分)의 용출량(溶出量)을 측정(測定)하고 Fly ash를 토양(土壤)에 처리(處理)한 경우 토양물리성(土壤物理性)의 변화(變化)를 조사(調査)하였다. Fly ash의 주요결정광물(主要結晶鑛物)은 mullite와 석영(石英)이었다. 증류수(蒸溜水)보다 Acetic acid로 Fly ash를 추출(抽出)할 경우 훨씬 많은 양(量)의 무기성분(無機成分)이 용출(溶出)되었다. 이때 Si 및 Al는 증류수(蒸溜水)에 의(依)해서 거의 용출(溶出)되지 않았다. 토양(土壤)의 투수성(透水性) 및 포장용수량(圃場容水量)은 Fly ash를 토양(土壤)에 10% 이하(以下) 첨가(添加)하면 향상(向上)되었으나 그 이상(以上) 처리시(處理時)에는 저하(低下)되었다. 토양(土壤)의 신축성(伸縮性) 및 경도(硬度)는 Fly ash를 10% 이하(以下)로 처리(處理)할 경우 큰 영향(影響)을 받지 않았다.

• Applied Biological Chemistry
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• 제38권2호
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• pp.147-150
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• 1995

에탄올처리 찰가자미껍질 젤라틴의 젤라틴농도, pH, 정치온도 및 시간과 같은 겔화조건에 대한 물리적 특성 및 색조의 변화를 측정하였다. 젤라틴의 농도가 증가할수록 겔강도, 녹는점과 같은 물리적 특성은 증가하였고, 일정농도에서의 이러한 값들은 에탄올처리한 젤라틴이 무처리한 젤라틴에 비하여 컸다. 젤라틴 졸의 pH가 에탄올처리한 젤라틴의 경우 6.0일 때, 무처리한 젤라틴의 경우 5.0일 때, 겔강도, 졸화온도 및 겔화온도가 가장 높았고, 이를 벗어난 $pH\;5.0{\sim}7.0$의 범위에서는 서서히 감소하였으며, pH 5.0이하 및 pH 9.0이상에서는 급격히 감소하였다. 젤라틴 졸을 겔화시키기 위하여 정치시키는 온도의 경우 낮을수록, 정치시키는 시간의 경우 길어질수록 겔강도 및 졸화온도는 높았다. 겔화조건을 동일하게 하였을 때 에탄올처리한 젤라틴이 무처리한 젤라틴보다 물리적 특성값이 높게 나타났다.

• 공업화학
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• 제16권3호
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• pp.342-347
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• 2005

하이퍼브랜치 폴리올(HBP-16, 32, 64)과 acrylic acid로부터 광경화형 하이퍼브랜치 아크릴레이트를 합성하였고, 그 물성을 조사하였다. TGA로 측정한 UV 경화필름의 열안정성은 관능기 수가 증가할수록 좀더 높은 온도로 이동하였다. 또한 아크릴 레이트의 관능기 수가 증가할수록 경도, 내마모성, 인장강도가 우수하였으며, 내후성 테스트에서는 아크릴레이트의 관능기수가 증가할수록 황변 지수 값이 증가하는 결과를 보여주었다.

• Elastomers and Composites
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• 제20권1호
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• pp.13-24
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• 1985

It is generally agreed that strong linkages exist between rubber chains and reinforcing filler particles. The purpose of this study is to examine the effect of rubber-filler attachments on the various mechanical properties of the rubber. In particular, the modulus and strength will be altered by these attachments. For this study, the curing properties are examined by means of ODR (Oscillating Disk Rheometer), the physical properties by means of Instrong. The results of this study can be summarized as follows. In the ODR test, the carbon black filled stock has shorter scorch time than gum stock and, the silica and clay filled stock has longer scorch time than gum stock. In the modulus, ten sile and swelling properties, the vulcanizates filled with carbon black had higher those values than inorganic filler loaded NR vulcanizates, but the rebound rate showed that the silica filled NR vulcanizates was lower than other inorganic filler contained NR vulcanizates and the ISAF filled NR vulcanizates was lower than other carbon block contained NR vulcanizates.

• 통합자연과학논문집
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• 제4권3호
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• pp.182-186
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• 2011

Chemical modification of porous silicon surface has been investigated to have different physical surface properties. Porous silicon modified with dodecyl functionality exhibits hydrophobic feature, however the oxidation of porous silicon to modify with hydroxyl group displays hydrophilic properties. Surface characterization for both dodecyl and hydroxyl derivatized porous silicon was investigated by FT-IR spectroscopy. To determine the surface coverage, the amine functionalized surface was reduced by dithiothreitol (DTT) and the released 2-thiopyridone was quantified by UV/vis spectroscopy.

• 한국토양비료학회지
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• 제42권별호
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• pp.28-52
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• 2009

• 통합자연과학논문집
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• 제4권3호
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• pp.187-191
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• 2011

The differences of properties for both single-layered and multi-layered porous silicon were investigated. Multistructured porous silicons such as DBR or rugate porous silicon exhibit strong reflection resonances providing the reflection of a specific wavelength in the optical reflectivity spectrum. DBR PSi displays a square varying porosity gradient in the direction perpendicular to the plane of the filter but a sinusoidally varying porosity gradient was obtained for rugate PSi.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3810-3816
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• 2012

Here we report our recent result of a new semiconductor material, which has an asymmetric structure. The synthesized molecules consist of anthracene and thiophene connected by bridged ethylene and substituted with hexyl or dodecyl groups as pendants. The semiconductors were synthesized using a McMurry coupling reaction between anthracene-2-carbaldehyde and corresponding 5-hexyl(or dodecyl)thiophene-2-carbaldehyde. A first investigation of synthesized asymmetry AVHT (9a) and AVDT (9b) for the physical properties showed that they have high oxidation potential and thermal stability. The devices prepared by using AVHT (9a) and AVDT (9b) showed the mobility of $2.6{\times}10^{-2}cm^2/Vs$ and $4.4{\times}10^{-3}cm^2/Vs$, respectively, in solution processed OTFTs.

• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.618-622
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• 2009

The new candidates for OTFTs, which were composed of naphthalene, anthracene, benzo[1,2-b:4,5-b’]dithiophene and 2-decylbithiophene end-capper were synthesized under Suzuki coupling reaction conditions. All of the oligomers were characterized by FT-IR, mass analysis, UV-vis, PL spectrum, cyclic voltametry (CV), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), $^1H-NMR\;and\;^{13}C-NMR$. Investigation of physical properties showed that all of the oligomers have higher oxidation potential and good thermal stability. Especially, DBT-DtB-DBT is soluble in common solvents and suitable for low cost processing technologies.