• Composites Research
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• v.24 no.2
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• pp.30-37
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• 2011

Analysis of wettability between epoxy resin and glass fabric was studied. The mixing ratios of epoxy resin and anhydride hardener were varied as 1:0.5, l:l and l:1.2. Catalyst content was fixed as 0.1wt% of the mixed resin. A curing analysis by differential scanning calorimeter(DSC) showed a possible impregnation of the mixed resin at the room temperature. An effective contact angle of the mixed epoxy resin drop onto the glass fabric being preset on a flat glass plate was measured as a function of time. The wet area of the epoxy resin drop was also measured. Behaviors of the contact angle, the droplet height, the neat wet area and the coefficient of wettability were used to evaluate the wettability of the epoxy resin onto the glass fabric. It was concluded that the equivalent ratio of 1: 1.2 was the most suitable for the wettability.

• Journal of Adhesion and Interface
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• v.11 no.4
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• pp.149-154
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• 2010

Interfacial evaluation was investigated for single-carbon fiber/phenolic and carbon nanotube (CNT)-phenolic composites by micromechanical technique and electrical resistance measurement combined with wettability test. Compressive strength of pure phenol and CNT-phenolic composites were compared using Broutman specimen. The contact resistance of CNT-phenolic composites was obtained using a gradient specimen by two and four-point methods. Surface energies and wettability by dynamic contact angle measurement were measured using Wilhelmy plate technique. Since hydrophobic domains are formed as heterogeneous microstructure of CNT in the surface, the dynamic contact angle exhibited more than $90^{\circ}$. CNT-phenolic composites exhibited a higher apparent modulus than neat phenolic case due to better stress transferring effect. Work of adhesion, $W_a$ between single-carbon fiber and CNT-phenolic composites exhibited higher than neat phenolic resin due to the enhanced viscosity by CNT addition. It was consistent with micro-failure patterns in microdroplet test.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.5 no.2
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• pp.58-66
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• 1991

This paper measured the characteristic of the thermal expansion, dielectric and conductivity to use $Sb_2O_3$ Filler in epoxy resin.The results are summarized as follow : 1 ) In the [$155^{\circ}C$] 1, The coefficient of thermal expansion increasing temperature obtained 8.19 in the case of pure epoxy resin and $4.5{\times}10^{-5}$ in the case of the mixing 7[%].2) The peak point of $\varepsilon\iota, \varepsilon\rho$ increasing $Sb_2O_3$ mixing ratio moved on the part of the high temperature. 3) The conductivity value increasing temperature shows the corner on the part of the Tg and it's Value became low the sample material with mixing I[%] than in case of pure epoxy resin.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.59-60
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• 2009

PAI-CS 나노하이브리드 절연코팅의 표면접착과 기계적 강도 및 내아크 내구성에 대하여 실험 분석하였다. 졸-겔법으로 PAI의 강화입자로 선택한 나노 CS는 메트릭스 수지와의 상안정성이 잘 이루어졌다. 나노경도를 측정한 결과 순수 PAI수지와 비교하여 CS첨가량이 증가함에 따라 경도와 탄성율 그리고 강성이 개선되고 있다. 한편 실란처리 방법에 따라 경 도와 탄성율의 개선폭이 달라지는 경향이 있어 제조시 적절한 실란처리에 의한 표면제어가 필요한 것으로 나타났다. 전기적 표면 내아크시험에서 순수 수지와 비교하여 우수한 내구성을 가지고 있어서 이는 서지와 부분방전 등에 노출되는 전력용 절연 코팅으로 사용이 기대된다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.248-254
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• 2005

This paper presents a quantitative method of sequential separation of $^{90}Sr,\;^{241}Am$ and Pu nuclides with an anion exchange resin and a Sr-Spec resin. The Pu isotopes were purified with an anion exchange resin. The americium and strontium fractions were separated from the matrix elements with an oxalate co-precipitation method. Americium fraction was separated from the strontium fraction with iron co-precipitation method and purified from lanthanides with anion exchange resin. Strontium-90 was purified from other hindrance elements with the Sr-Spec resin after oxalate co-precipitation. The measurement of Pu and Am isotopes was carried out by an ${\alpha}$-spectrometer. Strontium-90 was measured by a liquid scintillation counter. The radiochemical procedure of $^{90}Sr,\;^{241}Am$ and Pu nuclides investigated in this study has been validated by application to IAEA-Reference soils.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.210.2-210
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• 1978

전보의 glutathione의 최적 추출조건에 의한 추출액을 이온교환수지(Dowe xl-x2, Dowex 50w-x8)에 통과시켜 NAD와 glutathione을 분리하여 각각 paper chromatography로 확인한 결과 authentic Rf치와 일치하였다. 또 glutathione 함유액 부분을 2가구리 화합물로 처리한 동염처리 정제법을 이용하여 순수 glutathione 함유액을 얻었다. 또 chelate제도 sodium gluconate를 0.02％ 처리할때 glutathione 최종 수율이 66.2％에서 76.8％로 증가하였다. 이 순수용액을 50％ ethanol로 처리하여 crude glutathione 결정을 얻었다.

• KSBB Journal
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• v.9 no.1
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• pp.35-39
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• 1994

Separation of pure fructo-oligosaccharides from the mixed solution of glucose, sucrose and fructo-oligosaccharides was studied using a cationic ion-exchange resin column. Optimum separation conditions, i.e., temperature, feeding rate and the ratio of column vs. diameter were evaluated, which were found to be $85^{\circ}C$, $0.25h^{-1}$ and 30, respectively. At the optimized separation conditions, high-purity fructo-oligosaccharides up to 96% were obtained and the total recovery yield was about 66% after four cycles. After the chromatographic separation, purification to remove the salts and color in pure fructo-oligosaccharides solution was successfully conducted using the mixed-bed of cationic and anionic ionexchange resin columns.

• Proceedings of the KSEG Conference
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• 2002.04a
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• pp.275-284
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• 2002

서울 북부지역에 위치하는 북한산 일대의 지역단위 지하수 함양량 산정에 대하여 물수지 분석법과 SCS-CN방법을 이용하였다. 물수지분석법에는 Coutagne 공식과 Turc 공식을, SCS-CN방법에는 직접유출율과 누가침투율을 계산하여 평균 지하수 함양량을 산정하였다. 물수지분석법인 Coutagne 공식과 Turc 공식에서 평균 21.36%가 지하수 함양량으로 산출되었다. SCS-CN 방법에서는 직접유출율과 침투율을 계산하여 산정한 결과 지하수함양량은 30.07%로 추정되었다. 여기서 북한산 일대의 기반암을 경계로 상당량이 기저유출(baseflow)의 형태로 유출되기 때문에, 기저유출량 10.9%을 제외한 19.17%를 순수 지하수함양량으로 결정하였다. 누가침투율을 이용한 지하수함양량은 약22.0%로 산정되었다. 물수지분석법과 SCS-CN 방법들을 이용하여, 북한산 지역의 지하수 함양량을 산출한 결과 평균 약 20.84%로 산정되었다.

• The Optical Journal
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• s.133
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• pp.14-15
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• 2011

국내에서 폰카메라용 렌즈 금형의 독보적인 기술력을 보유한 한국와이다(대표 장해산)는 카메라폰용 8Cavity와 호환이 되는 16Cavity 렌즈 금형을 국내 최초로 개발했다고 밝혔다. 순수 국내 기술로 개발된 호환형의 8 & 16Cavity 렌즈 금형은 렌즈 생산을 2배 이상 늘릴 수 있어 짧은 시간 내에 대량 양산이 가능할뿐만 아니라 수지의 양도 기존의 절반으로 줄여 비용절감 효과도 가져왔다.

• Journal of Conservation Science
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• v.25 no.1
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• pp.77-86
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• 2009

The physical properties of the epoxy resins were studied with an addition of filler content and the application of artificial weathering test. When talc as a filler was added to the epoxy resin (L-30), the water resistance seemed to be increased because of the results of the reducing of water absorption rate and the increasing of contact angle. Although the adhesive strength of epoxy resins was not affected by the increasing amount of talc, its compressive strength was reduced. The physical properties of the epoxy resins had different trends according to the site environments. The artificial weathering test with the change of temperature and humidity showed that the changes of water absorption rate and colour differences of the epoxy resins containing talc were lower than the pure epoxy resin itself. However, the contact angle was higher. The artificial weathering test with ultraviolet irradiations showed the opposite result; the damage of epoxy resins was increased with the increasing of talc content. These mean the site environment of the stone monuments should be considered to determine the content of talc added to increase the durability of epoxy resin.