• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.191-192
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• 2000

New copolyimides containing nitrile side group were synthesized from copolymerization of pyromellitic dianhydride, m-phenylene diamine and 3,5-diaminobenzonitrile and subsequent thermal imidization of the resulting poly(amic acid). Crystallinity, glass transition temperature and initial decomposition temperature of copolyimides were almost identical to those of homo polyimide prepared from PMDA and m-PDA. Change of pretilt angle induced by the orientation layer of resulting copolyimide was investigated by using a nitrile-containg nematic liquid crystal cell after rubbing. As the content of polar nitrile group was increased in the copolymer, pretilt angle was increased from $3.65^{\circ}$ to $6.49^{\circ}$. The mechanism of this was speculated as the dipolar interaction between the liquid crystal and nitrile groups in copolyimide.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.2891-2894
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• 2014

The effects of mechanical activation of carbon black on the processing and properties of butadiene nitrile rubber were studied. Mechanical activation of carbon black caused an improvement in the physical and mechanical properties of the butadiene-nitrile rubber, BNR-18AMN. The optimum activation time that would afford rubber with improved properties was established.

• Fibers and Polymers
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• 제1권2호
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• pp.111-115
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• 2000

The effects of nitrile group substitution onto aromatic polyamide backbone on the gas permeability and permselectivity of the polymers are examined. The gas permeability of aromatic polyamides increase with increasing the content of nitrile group substitution, whereas the permselectivity decreases with increasing the nitrile group contents. The effects of chain linrearity on the permeability and permselectivity are also examined. The non-linearity of the polymers increases the permeability. These behaviors are interpreted in terms of chain packing and crystallinity of the aromatic polyamides.

• Archives of Pharmacal Research
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• 제11권4호
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• pp.285-291
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• 1988

2-mercaptoethanol, thioglycolic acid, glutathione, 3-mercapto-1, 2-propanediol and 3-mercapto-2-butanol showed catalytic activities on the hydrolysis of $\alpha$-amino-phenylacetonitrile to phenylglycineamide at the rate of 12.19 $\times$ $10^{-2}$, 8.03 $\times$ $10^[-2}$, 6.83 $\times$ $10^{-2}$, 8.60 $\times$ $10^{-2}$ and 6.04 $\times$ $10^{-2}$ mM $min^{-1}$, respectively. hte hydrolysis rate was faster in buffer than in water. The hydrolysis of the nitrile compound to phenylglycine was limited.

• Elastomers and Composites
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• 제53권4호
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• pp.195-201
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• 2018

Three kinds of rubber compounds were prepared, and their underwater acoustical properties were investigated for anechoic coating. Dynamic mechanical properties of the rubber compounds were measured using a dynamic mechanical analyzer and extended to 100 kHz using time-temperature superposition. The sound speed, reflection coefficient, and attenuation constant were calculated. Silicone rubber showed the lowest reflection coefficient, and nitrile rubber showed the highest attenuation constant. The acoustic properties of nitrile rubber compounds with various compositions were investigated. The sound speed, reflection coefficient, and transmission coefficient of the nitrile rubber in the frequency range of 200-1000 kHz were measured in a water-filled tank.

• 대한화학회지
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• 제67권4호
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• pp.306-310
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• 2023

• 한국미생물·생명공학회지
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• 제20권5호
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• pp.614-618
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• 1992

Brevibacterium CH1의 회분배양 결과 최적의 초기 포도당 농도는 $20g/{\ell}$이었고, 균체의 최대 성장속도는 $0.21h^{-1}$이었다. pH 를 조절하여 줌으로써 균체농도와 효소의 비활성이 각각 20, 30 정도 증가하였다. 따라서 pH 조절은 균체농도 및 효소생성에 상당한 영향을 주는 것을 알 수 있었다. M3 배지를 연속적으로 공급하면서 유가식 회분배양 한 결과 88시간 배양 후 균체농도는 $68g/{\ell}$로 고농도 배양이 되었으며, 비활성은 6.1units/mg으로 유지되었다. 효소의 총활성은 배양시간에 따라 증가하여 80시간 배양 후 최대 414.8 units/$m{\ell}$ 이었으며, 회분배양에 비해 4.4배 증가하였다. 이 경우에 Yx/s(cell growth yield)는 0.68g cells/g glucose consumed이었다.

• 대한화학회지
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• 제10권1호
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• pp.25-31
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• 1966

폴리아크릴로니트릴을 加熱할 때 着色과 同時에 構造變化가 있다는 것은 잘 알려진 事實이며 이것은 部分水素化나프틸리딘型環을 形成함에 基因하는 것으로 알려지고 있다. 本硏究는 이와 같은 構造變化의 反應을 動力學的 및 統計學的으로 取扱하여 지금까지 알려지지 않았던 새로운 事實들을 發見하였다. 첫째로 폴리아크릴로니트릴을 加熱할 때의 니트릴基의 減少는 一次反應이라는 것이며 이는 環形成反應이 긴連鎖反應으로 이루어지지 않는다는 것을 말해 주는 것이다. 다시 말하면 環形成時의 kinetic chain length는 極히 짧다는 것이다. 또 本 構造變化는 반드시 分子間反應(架橋結合)이 아니드라도, 일어날 수 있다는 것을 證明했다. 둘째로 環形成으로 니트릴基가 減少할 때 19~22%의 니트릴基가 殘存한다는 것이며 이를 統計學的으로 解析해본 結果 19.2%라는 計算値를 얻었으며 이는 實驗値와 잘 맞는 數値이다.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.700-703
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• 2010

• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.2083-2086
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• 2011