• 공업화학
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• 제9권4호
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• pp.509-515
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• 1998

커피폐기물을 원료로 하여 염화아연으로 화학적 활성화시켜 커피활성탄 (activated coffee char)을 제조하였다. 이 연구는 roasting과정, 탄화과정, 활성화, 그리고 수세 및 건조의 공정으로 수행되었다. Roasting 과정은 $300{\sim}400^{\circ}C$에서 10분간 수행되었다. 탄화과정의 적절한 조건은 $650^{\circ}C$에서 1시간인 것으로 나타났다. 화학적 활성화에 있어서 가장 중요한 parameter는 활성화제와 coffee char의 화학비인 것을 알 수 있었다. $N_2$ gas를 이용하여 77K에서 제조된 커피활성탄의 BET 비표면적과 BJH 세공용적을 측정하였다. 염화아연에 의해 활성화되어 제조된 coffee char의 비표면적이 $1110{\sim}1580m^2/g$로 분석되었으며 세공용적은 $0.51{\sim}0.81cm^3/g$로 각각 분석되었다. SEM은 세공과 coffee char의 표면관찰에 이용되었다. 분석결과, 활성화 표면과 많은 세공이 형성되어 있는 것을 보였다. 커피폐기물을 이용한 activated coffee char의 제조가 성공적으로 수행되었으며, 이는 폐기물을 이용한 자원 개발의 가능성을 보여주었다.

• 약학회지
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• 제52권6호
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• pp.471-479
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• 2008

The purpose of this study is to investigate the best way that Oriental medicine contributes for activation of pharmacy management after the separation of prescribing and dispensing practice since July 2000. In order to investigate current pharmacy conditions for handling of Oriental medicine and many problems for administering the Oriental medicine to patients, a questionnaire was written with a list of questions related to pharmacy management with Oriental medicine, and given to 58 subjects via fax or personal visit during the period of April 21 to 30, 2003. The research results was as follows; In th 58 subjects, 45 subjects (77.6%) were pharmacists with a licence for dispensing Oriental medicine. 70.7% of subjects most likely preferred to extract granule as administering type of oriental medicine. About the motivation using Oriental medicine, the reason for activation of pharmacy management was 39.7%, second, the reason for resolving the limitation of treatment over western medicine was 25.9%. Oriental medicine for patients was mainly administered by recommendation with pharmacist (65.5%). In comparison with after and before the separation of prescribing and dispensing, 51.7% of subjects answered that sale volume was decreased after the separation. Concerning the ratio of total sales volume to Oriental medicine within 5 years, 50% of subjects expected that sales volume will increase positively. About treating Oriental medcine, 34.5% of subjects thought the problem is the regulation by limiting 100 kinds of formulary. The most important factor for increasing Oriental medicine selling amount was continueous education for various information of oriental medicine in case of 44.8% of sujects. The best pharmacy to handle oriental medicine was community pharmacy (36.2%). It was expressed the reason why many pharmacists have not been treated oriental medicine because lots of time needs for dispensing prescription from clinics in these 4 years after the separation of prescribing and dispensing. These results lead to the conclusion that the Oriental medicine at pharmacy will greatly increase within 5 years and will be very important portion for pharmacy management.

• Carbon letters
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• 제9권4호
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• pp.298-302
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• 2008

Carbon blacks could be used as the filler for the electromagnetic interference (EMI) shielding. The poly vinyl alcohol (PVA) and polyvinylidene fluoride (PVDF) were used as the matrix for the carbon black fillers. Porous carbon blacks were prepared by $CO_2$ activation. The activation was performed by treating the carbon blacks in $CO_2$ to different degrees of burnoff. During the activation, the enlargement of pore diameters, and development of microporous and mesoporous structures were introduced in the carbon blacks, resulting in an increase of extremely large specific surface areas. The porosity of carbon blacks was an increasing function of the degree of burn-off. The surface area increased from $80\;m^2/g$ to $1142\;m^2/g$ and the total pore volume increased from $0.14073\;cc{\cdot}g^{-1}$ to $0.9343\;cc{\cdot}g^{-1}$. Also, the C=O functional group characterized by aldehydes, ketones, carboxylic acids and esters was enhanced during the activation process. The EMI shielding effectiveness (SE) of raw N330 carbon blacks filled with PVA was about 1 dB and those of the activated carbon blacks increased to the values between 6 and 9 dB. The EMI SE of raw N330 carbon blacks filled with PVDF was about 7 dB and the EMI SE increased to the range from 11 to 15 dB by the activation.

• 한국염색가공학회지
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• 제2권4호
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• pp.231-236
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• 1990

The diffusion coefficient of C.I. Disperse Red 4 in the dyeing of carrier-pretreated poly (ethylene terephthalate) film was Investigated by Sekido's film-rolled method. From the result it was shown that the diffusion coefficient increases exponentially with the content-ration of carrier in the film, and, for the films containing same concentration of carrier, the carrier effect was enhanced with the molar volume of the carriers. The greater carrier effect was accompanied by the decrease in diffusion activation energy and entropy, which shows that the carrier with larger molar volume plasticizes PET film to more extent.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.985-986
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• 2013

• 한국수산과학회지
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• 제10권4호
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• pp.213-220
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• 1977

제 1보에서 측정한 해수의 비전도도 값을 사용하여 본 논문에서 저자들이 제안한 식으로부터 얻어진 당량 전도도를 Arrhenius plot 했을 때 활성화에너지, ${\Delta}E$는 압력 및 농도변화에 따라 $3.0\~4.0\;Kcal/mole$ 범위 이었다, 압력변화에 따른 활성화 부피변화의 평균치 측정된 온도와 압력에서 $-0.27\~-1.30\;cm^3/mole$ 범위였다. (염소량이 $6.228\%_{\circ},-1.65\~\;-0.32cm^3/mole;\;9.063\%_{\circ},\;-1.18\~-0.27cm^3/mole;\;11.628\%_{\circ},\;-1.53\~-0.07cm^3/mole;\;14.311\%_{\circ},\;-1.37\~-0.35cm^3/mole;\;16.408\%_{\circ},\;-1.18\~-0.47cm^3/mole;\;19.372\%_{\circ},\;-1.53\~-0.29cm^3/mole$)이들값으로 해수의 성질과 물의구조를 정성적으로 밝힐 수 있었다. 본 논문 정리를 위해 조언하여 주신 원중훈교수님께 감사드립니다.

• 대한화학회지
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• 제35권1호
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• pp.64-69
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• 1991

아세토니트릴 용매 중에서 p-methylphenacyl arenesulfonate와 피리딘의 반응을 1∼2000 bars 및 35∼55$^{\circ}C$에서 전기전도도법으로 측정하였다. 반응속도는 온도와 압력의 증가에 따라 증가하였으며, 이탈기에 전자받개 치환기가 도입됨에 따라 증가하였다. 활성화엔탄피, 엔트로피 및 부피로부터 이 반응은 전반적으로 S$_N$2 반응으로 진행되나 압력이 증가함에 따라 C${\cdots}$O 결합분열이 더욱 진전된 dissociative S$_N$2 반응으로 진행됨을 알 수 있었다.

• 한국분말재료학회지
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• 제6권1호
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• pp.81-87
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• 1999

Based on the pore filling theory, the microstructure evolution during liquid-phase sintering has been analyzed in terms of interrelationship between average grain size and relative density. For constant liquid volume fraction, the microsturucture trajectories reduced to a single curve in a grain size(x)-density(y) map, regardless of grain growth constant. The slope of curves in the map was inversely proportional to average pore size, while it increased fapidly with liquid volume fraction. Increase in pore volume fraction retarded the densification considerably, but showed marginal effect on the slope. The activation energy of densification was predicted to be the same as that of grain growth as long as the liquid volume fraction is constant for any temperature range studied. The present analyses on microstricture evolution may demonstrate the usefulness of pore filling theory and provide a guideline for process optimization of liquid-phase sintering.

• 한국재료학회지
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• 제26권9호
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• pp.460-467
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• 2016

Activated carbons (ACs) have been used as EDLC (electric double-layer capacitor) electrode materials due to their high specific area, stability, and ecological advantages. In order to prepare ACs with high density and crystallinity, coal tar pitch (CTP) was activated by $K_2CO_3$ and the textural and electrochemical properties of the obtained ACs were investigated. Although the CTP ACs formed by $K_2CO_3$ activation had much smaller specific surface area and pore volume than did the CTP ACs formed by KOH activation, their volumetric specific capacitance (F/cc) levels as electrode materials for EDLC were comparable due to their higher density and micro-crystallinity. Structural characterization and EDLC-electrode performance were studied with different activation conditions of $CTP/K_2CO_3$ ratio, activation temperature, and activation period.

• 한국세라믹학회지
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• 제42권7호
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• pp.469-474
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• 2005

Activated Carbon Fibers (ACFs) are widely used as adsorbents in technologies related to pollution abatement due to their highly porous structure and large adsorption capacity. The porous structure and surface area of ACFs depends strongly on both the activation processes arid the nature .of the precursors. The chemical activation with hydroxides has recently been, of great interest as it permits the preparation of activated carbon fibers with highly developed porosity. In this work, OXI-PAN fiber used as precursor for the preparation of activated carbon fibers by chemical activation with KOH and NaOH. The affects of several activation conditions on the surface properties, pore size distribution and adsorption capacity of Ag ion and Iodine ion on ACFs studied.