• Journal of Adhesion and Interface
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• v.14 no.2
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• pp.82-87
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• 2013

Preliminary studies on the synthesis of magnetic nanoparticles including nanoporous carbon materials have been done via a direct carbonization process from resol, ferric nitrate and triblock copolymer F127. The results show that the nanoporous magnetite/carbon ($Fe_3O_4$/carbon) with a low $Fe_3O_4$ content (1 wt%) possesses an ordered 2-D hexagonal (p6mm) structure, uniform nanopores (3.6 nm), high surface areas (up to 635 $m^2/g$) and pore volumes (up to 0.48 $cm^3/g$). Magnetite nanoparticles with a small particle size (10.2 nm) were confined in the matrix of amorphous carbon frameworks with superparamagnetic property (7.7 emu/g). The nanoporous magnetite/carbon showed maximum adsorption amount (995 mg/g) of ibuprofen after 24 h at room temperature. The nanoporous magnetite/carbon was separated from solution easily by using a magnet. The nanoporous magnetite/carbon material is a good adsorbent for hydrophobic organic drug molecules, i.e. ibuprofen.

• Journal of the Korean Chemical Society
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• v.13 no.2
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• pp.177-180
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• 1969

5-Cyanopyrimidine derivatives were synthesized starting from 5-aminopyrimidine derivatives through the extended Sandmeyer reaction, and then these compounds were hydrolyzed to obtain pyrimidine-5-carboxylic acids. According to this procedure, 5-cyanopyrimidine derivatives and pyrimidine-5-carboxylic acid derivatives have been prepared in 62% and 65% yields, respectively, without any difficulties in removing impurities.

• Journal of the Korean Chemical Society
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• v.10 no.2
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• pp.51-53
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• 1966

A new conventional method for the preparation of 5-iodo, chloro-, and bromo-6-methyluracil by Sandmeyer reaction was described. According to this procedure, 5-halo-6-methyluracils have been prepared in high yields (up to 70%) without any difficulties to obtain highly pure products. No appreciable competing reaction was observed.

• Journal of Welding and Joining
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• v.13 no.4
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• pp.24-29
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• 1995

전자제품의 고기능화에 따라 Controller의 중요성은 점점 증대되고 있다. 따라서 Controller(이하 PCB라 칭함)의 제조 공정에서 납땜 관련 Board 재료, Flux, Flux 탄화 연기 등은 식물의 고사 현상등 지구환경을 위협하고 있다. 특히, 자동차 매연이나 도장 또는 PCB 납땜시 SOX, NOX, 탄화수소계등이 휘발하게 되며 아황산 가스 나 질소 산화물이 대기중에서 물과 반응하여 황산 또는 질산으로 변하여 PH 5.6이하 의 산성비를 내리게 한다. 이 산성비는 삼림피해 어류감소 등 생태계를 파괴하고 콘 크리트 철재등 건축 자재물을 부사시킨다. 또한 바람에 의해 인접국가에도 막대한 피해를 주고 있다. 특히 폐가전제품의 PCB 접합부에 산성비가 접촉되면 Pb 이온이 용출되어 토양 및 수질오염, 인체피해 등 심각한 영향을 미치게 된다. 최근 이와관련 세계 각국의 규제 움직임이 활발해지고 있어, 본 논문은 전자기기 제품의 심장인 PCB 와 관계된 환경오염 대상물질의 규제동향과 심각성 및 이에 대한 환경피해 Mechanism 을 분석하여 실장기술에 있어서 총체적인 환경대응 방안을 모색하고자 한다.

• Journal of the Korean Chemical Society
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• v.9 no.1
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• pp.29-32
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• 1965

A new conventional method for the preparation of 5-iodo-, chloro-and bromouracil by Sandmeyer reaction was described. According to this procedure, 5-halouracils have been prepared in high yields(up to 75%) without any difficulties to remove of impurities. No appreciable competing reaction was observed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.253-254
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• 2011

The purpose of this study is to investigate chloride ion adsoption property of cement mortar using nitrite type hydrocalumite(calumite) with self-corrosion inhibition function. Superior corrosion inhibition function of the VA/E/MMA-modified mortars with calumite was ascertained from accelerated corrosion test in the previous study. In this study, VA/E/MMA-modified mortars with calumite were prepared with calumite contents of 0, 5, 10% and polymer-binder ratio of 0, 10%, and tested for chloride ion adsorption to make it clear how calumite gives self-corrosion inhibition function to cement mortar. As a result, chloride ion adsorption property of VA/E/MMA-modified mortars with calumite was improved by increasing calumite contents compared to unmodified mortar regardless of using VA/E/MMA terpolymer powder or not.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.60-65
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• 1998

핵융합로 증식재용 Li$_2$TiO$_3$ 분말을 자발착화연소합성법으로 합성하였다. Li질산염과 Ti 질산염이 혼합된 전구용액은 연소반응을 위하여 가열되는 동안 침전물이 형성 되었지만 카르복실산기(carboxylic acid group)와 아민기(amine group)를 지닌 글라이신(glycine)이나 카르복실산기만을 가진 구연산(citric acid)과 아민기만을 가진 우레아(urea)를 흔합한 연료를 사용한 경우에는 연소합성반응이 일어나 분말을 쉽게 합성할 수 있었다. 또한 형성된 분말은 별도의 하소공정이 없더라도 원하는 결정상이 형성되었으며, 합성편 Li$_2$TiO$_3$ 분말은 비표면적이 15 $m^2$/g으로 약 30nm의 크기를 지닌 미세한 입자이었다.

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.75-77
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• 1965

A new method of synthesis of isobarbituric acid is described. With this method, isobarbituric acid can be synthesized both directly and conveniently. Yields of isobarbituric acid are up to 75 per cent.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.41-42
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• 2011

In this study, VA/E/MMA-modified mortars with nitrite-type hydrocalumite were prepared with various calumite contents and polymer binder-ratios, and tested for chloride ion penetration, carbonation and drying shrinkage. As a result, the chloride ion penetration and carbonation depths were somewhat increased with calumite contents, but those were remarkably decreased depending on the polymer-binder ratios. The 28-d drying shrinkage showed a tendency to increase with polymer-binder ratios and calumite contents. VA/E/MMA-Modified mortars with a calumite of 10 % were dissatisfied with KS requirements. Accordingly, a calumite content of 5 % for the VA/E/MMA-modified mortars with calumite is recommended.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.53-55
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• 2013

Nitrite-Type hydrocalumite (calumite) is a material that can provied a self-corrosion inhibition function to the reinforce concrete. In this study, bisphnol A·F type epoxy-midified mortars without hardner contaning calumite is prepared with various polimer-binder ratios, calumite contents and tow types of curing condition, and tested for flexural and compressive strength tensile strength and corrosion-inhibition. As a result, in the case of wet/dry curing condition, strengths of bisphnol A·F type epoxy-modified mortars without hardener contaning calumite is inclined to decrease with increasing of polymer-binder ratio and calumite content. However, dry cured specimens are slightly improved by using bisphnol A·F type epoxy resin. Finally, regardless of polymer-binder ratios and calumite contents, corrosion-inhibition of bisphnol A·F type epoxy-modified mortars without hardener containing calumite is superior than that of unmodified mortar.