• Carbon letters
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• 제11권3호
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• pp.216-223
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• 2010

Two-types of ionically modified multi-walled carbon nanotube (MWNTs) based sensors were developed by radiationinduced graft polymerization using vinyl monomers such as 3-(butyl imidazol)-2-(hydroxyl)propyl methyl methacrylate and 1-[(4-ethenylphenyl)methyl]-3-buthyl-imidazolium chloride with ionic properties, in aqueous solution at room temperature. Subsequently, the tyrosinase-immobilized biosensor was fabricated by a hand-casting of the ionic property-modified MWNTs, tyrosinase, and chitosan solution as a binder onto ITO glass surface. The sensing ranges of the tyrosinase-biosensor for phenol in phosphate buffer solution was in the range of 0.005~0.2 mM. The total phenolic compounds mainly such as caffeine of the tyrosinase-immobilized biosensor for commercial coffee were also determined.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제26회 춘계학술대회논문집
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• pp.31-35
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• 2006

Degradation characteristics of filament-winded composites due to accelerated environmental aging have been evaluated under high temperature, water immersion and thermal impact conditions. Two kinds of laminated composites coated by an urethane resin have been used: carbon-fiber reinforced epoxy(T700/Epon-826, CFRP) and glass-fiber reinforced phenolic (E-glass/phenolic, GFRP). For tensile strength of $0^{\circ}$ composites, CFRP did high reduction by 25% under the influence of high temperature and water while CFRP showed little degradation. However for water-immersed $90^{\circ}$ composites both CFRP and GFRP showed high reduction in tensile strength. Bending strength and modulus of $90^{\circ}$ composites were largely reduced in water-immersion as well as high temperature environment. Urethane coating on the composite surface improved the bending properties by 20%, however hardly showed such improvement for water-immersed $90^{\circ}$ composites.

• 한국수산과학회지
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• 제28권6호
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• pp.761-769
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• 1995

About 2.1g of pale yellow flavor concentrate was obtained from 10kg of chopped fresh ascidians through a Likens-Nickerson steam distilllation/solvent extraction. These concentrates could be fractionated to neutral $(91.5\%),\;basic\;(1.0\%),\;phenolic\;(3.2\%),\;and\;acidic\;(4.3\%)$ fractions. Total 65 volatile compounds were identified from those concentrates. The neutral fraction was representative flavor fraction which showed a similar flavor of total steam distillates of ascidian. The major compounds $(38.2\%\;of\;neutral\;fraction)$ were identified as carbon atoms 8 to 10 of alcohols. Among these volatile alcohols, 1-octanol, 2,7-decadien-1-o1, 3-octen-l-01, 7-decen-l-ol, and l-decanol were the dominent compounds found in neutral fraction. But the basic, phenolic, and acidic fractions differs from ascidian steam distillates flavor.

• 생약학회지
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• 제11권3_4호통권43호
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• pp.153-162
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• 1980

1) The hydroxy-substitution in the simple phenolic compounds follows an additivity rule in the chemical shifts of their aromatic carbon atoms. In para-and ortho-effects is a good agreement between calculated and measured values, but the meta-effect is not certain. 2) The additivity rule was applied to assign the chemical shifts of catechins. 3) The nuclear overhauser effect was applied to assign the chemical shifts of C-8 and C-6 atoms of catechins and their polymer. The signal of C-8 is lower in intensity and appear in lower field than C-6. 4) The results of the NOE were applied to determine the bonding positions of catechin units in the catechin dimer and trimer. The bonding positions are C-8a and C-8b atoms of the second and third catechin units. 5) It was tried to determine the conformation of the catechin dimer and trimer by analysing the signal shapes of C-3' and C-4' atoms in the catechol moieties. The catechol moieties lie in opposite side in the dimer and trimer structure. A combined analysis of $^{13}C-and\;^1H-NMR$ results lead to the suggestion that such a catechin polymer is a zigzag planar form.

• 한국세라믹학회지
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• 제34권1호
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• pp.56-62
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• 1997

탄화된 PAN 섬유, 페놀수지, 세라믹 결합체를 혼합하여 탄소섬유-세라믹복합체를 제조한 후 활성화시켜 PAN 섬유의 탄화온도에 따른 활성탄소섬유-세라믹복합체의 비표명적과 굽힘 강도변화를 연구하였다. 안정화 PAN 섬유를 80$0^{\circ}C$와 100$0^{\circ}C$에서 각각 탄화시켜 얻은 두 종류의 탄소섬유를 복합체 제작시편의 원료로 사용하였다. 탄소섬유-세라믹복합체를 10~90분간 CO2로 85$0^{\circ}C$에서 활성화시켜 얻은 두 종류의 활성복합체에 대한 물성 측정결과, 80$0^{\circ}C$로 PAN 섬유를 탄화시켜 만든 활성복합체의 burn-off이 37%에서 76%로 증가될 때 비표면적은 493m2/g에서 1090m2/g으로 증가하였으며, 굽힘강도는 4.5 MPa에서 1.4MPa로 감소하였다. 이 값들은 안정화 PAN 섬유의 탄화온도를 100$0^{\circ}C$로하여 활성복합체 시편이 나타내는 값보다 약 2배 정도 큰 값이었다. 비표면적, 굽힘강도 측정결과와 미세조직 관찰결과, PAN 섬유의 탄화온도가 활성복합체의 비표면적과 굽힘강도에 미치는 영향은 활성화시 탄소섬유와 페놀수지탄화체 또는 세라믹 필름간에 발생되는 결합력과 상대적인 수축율에 의해 결정되는 활성복합체의 구조특성에 기인된 것으로 해석하였다.

• Carbon letters
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• 제14권1호
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• pp.40-44
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• 2013

The bipolar plate is the most important and most costly component of proton exchange membrane fuel cells. The development of a suitable low density bipolar plate is scientifically and technically challenging due to the need to maintain high electrical conductivity and mechanical properties. Here, bipolar plates were developed from different particle sizes of natural and expanded graphite with phenolic resin as a polymeric matrix. It was observed that the particle size of the reinforcement significantly influences the mechanical and electrical properties of a composite bipolar plate. The composite bipolar plate based on expanded graphite gives the desired mechanical and electrical properties as per the US Department of Energy target, with a bulk density of 1.55 $g.cm^{-3}$ as compared to that of ~1.87 $g.cm^{-3}$ for a composite plate based on natural graphite (NG). Although the bulk density of the expanded-graphite-based composite plate is ~20% less than that of the NG-based plate, the I-V performance of the expanded graphite plate is superior to that of the NG plate as a consequence of the higher conductivity. The expanded graphite plate can thus be used as an electromagnetic interference shielding material.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.1065-1068
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• 1998

On the study, The activated carbon assemblies(ACA) were prepared by activation of the coated glass mate(woven type) with phenolic resin at $700^{\circ}C$ under $N_2$ after drying and curing processes. Surface of the ACA was continuously modified with $N_2$, $CO_2$ or $NH_3$ at $700^{\circ}C$ for 2 hour for comparison of adsorptive characteristics between the ACA and commercial activated carbon cloth. The ACA showed high surface areas up to $2440\;m^2/g$ when converted into the coated carbon base, and the surface was investigated by FT-IR and XPS. The basic ACA modified with $NH_3$ displayed the efficient removal capability of $SO_2$, which is 75% of that in commercial activated carbon cloth. Therefore, it has proved the applicability of ACA as an inexpensive materials for Dry de-SOX system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.717-720
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• 1998

On the study, The activated carbon assemblies(ACA) were prepared by activation of the coated glass mat(woven type) with phenolic resin at $700^{\circ}C$ under $N_2$ after drying and curing processes. Surface of the ACA was continuously modified with $N_2$, $CO_2$ or $NH_3$ at $700^{\circ}C$ for 2 hour for comparison of adsorptive characteristics between the ACA and commercial activated carbon cloth. The ACA showed high surface areas up to $2440\;m^2/g$ when converted into the coated carbon base, and the surface was investigated by FT-IR and XPS. The basic ACA modified with $NH_3$ displayed the efficient removal capability of $SO_2$, which is 75% of that in commercial activated carbon cloth. Therefore, it has proved the applicability of ACA as an inexpensive materials for Dry de-SOX system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.397-400
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• 1998

On the study, The activated carbon assemblies(ACA) were prepared by activation of the coated glass mat(woven type) with phenolic resin at $700^{\circ}C$ under $N_2$ after drying and curing processes. Surface of the ACA was continuously modified with $N_2$, $CO_2$ or $NH_3$ at $700^{\circ}C$ for 2 hour for comparison of adsorptive characteristics between the ACA and commercial activated carbon cloth. The ACA showed high surface areas up to $2440\;m^2$/g when converted into the coated carbon base, and the surface was investigated by FT-IR and XPS. The basic ACA modified with $NH_3$ displayed the efficient removal capability of $SO_2$, which is 75% of that in commercial activated carbon cloth. Therefore, it has proved the applicability of ACA as an inexpensive materials for Dry de-SOX system.

• 폴리머
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• 제24권2호
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• pp.237-244
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• 2000

탄화 매트릭스의 전구체로 사용된 페놀수지에 세라믹 분말인 이규화몰리브덴 (MoSi$_2$)을 0, 4, 12, 20%의 중량비로 각각 고르게 분산시켜, 여기에 PAN계 탄소섬유를 함침하여 프리프레그법을 이용하여 일방향 탄소섬유/페놀수지 복합재료를 제조하였으며, 이를 다시 탄화(110$0^{\circ}C$) 시켜서 일방향 탄소/탄소 복합재료를 제작하였다. 본 연구에서는 난소/탄소 복합재료에 산화 억제제로 사용된 MoSi$_2$의 첨가량에 따른 복합재료의 산화거동을 산화분위기 하 600-100$0^{\circ}C$의 온도범위에서 조사하였다. 그 결과, MoSi$_2$를 함유한 탄소/탄소 복합재료는 복합재료 내치 기공 감소와 산소에 대한 유동 확산 방지막의 형성으로 인하여 카본 활성종이 방해를 받아 MoSi$_2$를 함유하지 않은 것에 비해 산화속도가 감소되어 내산화성이 향상되었다. 이는 산소의 공격에 대한 보호층을 형성하는 MoSi$_2$ 고유의 특성에 따른 영향이라 사료된다.