• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.94.2-94.2
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• 2011

In this work, multi-functional groups, i.e., nitrogen and oxygen, contained microporous carbons (MF-MCs) were prepared by the one step carbonization of the poly(vinylidene chloride-co-acrylonitrile-co-methyl methacryalte) (PVDC-AN-MMA) without activation. The electrochemical performance of MF-MCs was investigated as a function of carbonization temperature. It was found that MF-MCs had a high specific surface area over $800m^2/g$ without additional activation, resulting from the micropore's formation by the release of chlorine groups. In addition, although functional groups decreased, specific surface area was increased with increasing carbonization temperature, leading to the enhanced electrochemical performance. The pore size of the carbon distributed mainly in small micropore of 1.5 to 2 nm, which was idal for aqueous electrolyte. Indeed, the unique microstructure features, i.e. high specific surface area and optimized pore size provided high energy storage capability of MF-MCs. These results indicated that the microporous features of MF-MCs lead to feasible electron transfer during charge/discharge duration and the presence of nitrogen and oxygen groups on the MF-MCs electrode led to a pseudocapacitive reaction.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.571-576
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• 2000

Electrocatalytic effects for the reduction of thionyl chloride in $LiAICI_4/SOCl_2$ electrolyte solution containing Schiff base M(II) (M; Co and Fe) complexes are evaluated by determining kinetic parameters with cyclic voltammetry and chronoamperometry at a glassy carbon electrode. The charge transfer process during the reduction of thionyl chloride is affected by the concentration of the catalyst. The catalytic effects are demonstrated from both a shift of the reduction potential for the thionyl chloride toward a more positive direction and an increase in peak currents. Catalytic effects are larger in thionyl chloride solutions containing the binuclear [M(II) $_2$ (TSBP)] complex rather than mononuclear [M(II)(BSDT)] complexes. Significant improvements in the cell performance have been noted in terms of both thermodynamics and activation energy for the thionyl chloride reduction. The activation energy calculated from the Arrhenius plots is 4.5-5.9 kcal/mole at bare glassy carbon electrodes. The activation energy calculated for the catalyst containing solution is 3.3-4.9 kcalmole, depending on whether the temperature is lowered or rasied.

• Korean Journal of Veterinary Research
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• v.64 no.3
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• pp.29.1-29.8
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• 2024

The liver is a defense against infections due to its strategic location between the gastrointestinal and systemic circulations. In dogs and cats, infectious hepatitis encompasses a range of contagious diseases affecting the liver either directly or as part of a broader systemic infection, including bacterial, mycobacterial, viral, fungal, protozoal, parasitic, and rickettsial diseases. Catechins possess well-recognized natural antioxidant properties. This study investigated their therapeutic potential for applications in hepatology, evaluating whether catechins reduce hepatic inflammation in rats repeatedly exposed to carbon tetrachloride (CCl₄). Sprague-Dawley rats were given catechin 50 (C50) or 100 (C100) mg/kg body weight orally daily for 3 days. This treatment was given with or without concurrent intraperitoneal injections of CCl₄. Phosphate-buffered saline served as the vehicle control, while silymarin administered at 100 mg/kg was used as the positive control. Gross examination revealed significant enlargement, edema, and darker tissue in CCl₄-induced livers treated with vehicle. Additionally, spotty discoloration was observed on the surface. Kupffer cell activation suppressed the expression of inflammatory mediators, including inducible nitric oxide synthase (iNOS), in groups co-treated with catechin and CCl₄; this effect was reversed when catalase replaced catechin in CCl₄-injured rats. Catechin alleviates hepatic inflammation in rats repeatedly exposed to CCl₄; it also modulates the activation of Kupffer cells and monocytes. These results should lead to new treatments for liver inflammation in veterinary practice.

• Polymer(Korea)
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• v.36 no.6
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• pp.756-760
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• 2012

In this work, the coal tar pitch-based activated carbons (ACs) were prepared by KOH activation for electrode materials of supercapacitor. The effects of activation temperature on electrochemical performance of the ACs were investigated with cyclic voltammogram (CV) measurement. The textural and morphological properties of the ACs were measured by adsorption isotherms and field emission scanning electron microscope (FE-SEM) analyses, respectively. The experimental results indicated that the specific capacitance of the ACs increased with developing the micropore volume by activation temperature. As a result the specific capacitance of the ACs increased, owing to the development of micro pore volume of the ACs.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2141-2148
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• 2000

This study is to investigate changes of pore structure with different burn-off degree of steam activated carbons manufactured from domestic anthracite. The activated carbons were characterized by adsorption of nitrogen at 77 K. Steam activation substantially enhanced the porosity of the activated carbons. Burn-off increased linearly according to increasing activation time, and total pore volume and BET surface area increased with burn-off. Activation at $800^{\circ}C$ increased more micropore volume than that at $950^{\circ}C$. Activated carbons manufactured at high temperature had less microporosity than that at lower temperature, but had more developed macroporosity. The steam activation produced an enlargement of pore below $100{\AA}$ diameter in the activated carbons. Furthermore, the porosity in the $6{\sim}40{\AA}$ pore diameters range increased considerably with the degree of burn-off.

• Carbon letters
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• v.10 no.3
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• pp.198-201
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• 2009

Among other filters such as light filter, wave filter, air filter, ultra filter and filter paper, a novel adsorption filter from thermostable polyester nonwoven fabrics immobilized with functional super activated carbon by means of quinoline soluble, activateable isotropic pitch binder were developed in this study. The activated carbon precursor is available in the market branded as coconut shell based activated carbon(CCS-AC) produced by Dongyang Carbon Co. Ltd. BET-surface area of this precursor was $1,355\;m^2/g$, after KOH-activation it increased over $2,970\;m^2/g$ and was named as super activated carbon. In the preliminary research, this precursor was impregnated with $PdCl_2$(0.188 wt%) $KMnO_4$(3 wt%) and redox-agent(CuCl2, 0.577 wt%) in order to promote TOF up to 100/h and Selectivity up 99% and patented as a functional AC for the ethylene adsorption. The enhancement of the isotropic pitch binder to the AC-immobilized adsorption filter was BET-surface area upgraded by $266\;m^2/g$ and promoted the Iodine- and MB-adsorption by 1.4 times, respectively and also micro pore wide ranges < $5{\AA}{\sim}30\;{\AA}$ >.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.67-71
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• 1997

Activated carbons are the microporous carbonaceous adsorbents which are prepared from carbon-containing source materials such as wood, coal, lignite, peteroleum and sometimes synthetic high polymers. [1-2] Activated carbons shows an ability to adsorbe hydrocarbons of the gas phase. Activated carbons are used in the purification of many kinds of gas phases like hexane, benzene, toluene, gasoline, phenol etc.[3] In this study, cokes from bitminous coal were activated for the purpose of preparing the activated carbons by steam activation. The effect of the activation temperature, time, steam concentration and flow rate on the n-butane adsorption, burn off, surface area and average pore size of the activated carbons, were investigated. The adsorption characteristics of the activated carbons for gasoline are indirectly estimated by n-butane adsorption.

• Korean Journal of Materials Research
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• v.8 no.2
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• pp.114-119
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• 1998

등방성 피치계 탄소섬유를 Co$_{2}$gas중에서 등온산화시켜 활성탄소섬유를 제조하였다. 산화된 섬유의 비표면적은 BET장치를 이용하여 측정하였다. Burn-off가 증가하여도 반응속도는 크게 감소하지 않았으며, 80$0^{\circ}C$와 90$0^{\circ}C$에서 산화된 섬유의 비표면적은 40%-60%의 burn-off에서 급격히 증가하다가 60%이상에서 감소하였다. 110$0^{\circ}C$에서 산화된 시편은 40%이상 burn-off되어도 비표면적은 크게 증가하지 않고 60%를 지나서도 계속해서 표면적이 증가하는 현상을 나타내었다. 100$0^{\circ}C$에서 60.4%의 burn-off가 일어난 산화섬유의 비표면적은 3,614$m^2$/g로 가장 큰 값이 얻어졌다. 등방성 탄소섬유는 미세한 흑연결정립들이 무질서한 배향을 하고 있으며, 미세기공벽으로 작용할 수 있는 결정립층이 많기 때문에 활성탄소섬유 제조를 위한 원료로 적합하다고 판단된다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.125-126
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• 2021

Fly ash, has been widely used as one of the main supplementary cementitious materials (SCMs) in the world, to replace part of cement to significantly save energy and reduce greenhouse emission. Via mechanical activation, fly ash can replace more cement without impairing early age compressive strength. This study focuses on the strength-based evaluation of carbon dioxide emission for blended cement composite containing mechanically activated fly ash. Results indicate that under similar compressive strength, a prominent drop has been witnessed in embodied energy of binary cement and CO2 emission of the composite containing mechanically activated fly ash compared with those containing ordinary fly ash.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.117-124
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• 2002

Poly(acrylonitrile)(PAN) solutions in dimethylformamide(DMF) were electrospun to prepare webs consisting of 400nm ultra-fine fibers. The webs were oxidatively stabilized, activated by steam and resulted to be activated carbon fibers(ACFs). The specific surface area was $800\~1230 m^2/g$, which showed a trend of a decrease of the surface area with an increase in activation temperature, showing opposite behavior to the other ACFs. The activation energy of the stabilized fibers for the steam activation was determined as 29.2 kJ/mol to be relatively low indicating the easier activation than that of other carbonized fibers. The ACF webs were characterized by pore size and specific surface uea which would be related to the specific capacitance of the electrical double layer capacitor (EDLC). The specific capacitances measured were 27 F/g, 25 F/g, 22 F/g at the respective activation temperature of $700^{circ}C,\;750^{\circ}C\;800^{\circ}C$, showing similar trend with the specific surface area i.e., the higher activation temperature was, the lower specific capacitance resulted.