• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.6
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• pp.250-255
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• 2018

The CoCrMo as-built alloys prepared by 3D-printing process are studied on tensile strength, wear resistance, crystal structure and microstructure after complex heat-treatment including HIP. In this study, HIP treatment for removing micropores, ambient heat-treatment for formation of metal carbides, and solution heat-treatment for homogenization of the created metal carbides were tried and characterized for applying to artificial joint. The complex heat-treatment effects of the CoCrMo as-built alloys prepared by 3D-printing process were owing to the densification during HIP, formation of metal carbides and homogenization of the created metal carbides. The effects of the complex heat-treatment were confirmed by XRD, FE-SEM and EDS.

• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.461-465
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• 2008

The phase transformation in a film influences its surrounding. Effects of the precrystallization method, which removes influences on gate oxide caused by lateral crystallization, in metal-induced unilaterally crystallized polycrystalline silicon thin-film transistor devices and circuits were studied. Device by the method was shown to have a higher current drive, compared with conventional postcrystallized device. Moreover, we studied DC bias-induced changes in the performance of ring oscillator. PMOS inverters fabricated using precrystallized silicon films have very high dynamic and stable performance, compared with inverters fabricated using postcrystallized silicon films.

• Analytical Science and Technology
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• v.26 no.3
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• pp.205-210
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• 2013

For the synthesis of crystalline LAS glass by sol-gel method, the effect of operation conditions including metal alkoxide ratio, nucleating agent composition and heat treatment on the crystalline properties was experimentally investigated. The gelation time and crystallization temperature were proportionally affected by the mole ratio of TEOS in metal alkoxides solution. The addition of $TiO_2$ had an influence on the increasing of the gelation time, but the crystallization temperature was rarely dependent on the adding of nucleating agent. The crystallinity of LAS glass was improved by the nucleating agent under same heat treatment conditions.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.12.2-12.2
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• 2009

전자 디스플레이 산업의 중요성과 미래사회에서 요구되는 정보기기로써 유연한 기판을 사용한 소자에 대한 수요가 급격히 증가하고 있으며, 이들 산업에 응용되기 위해서는 저비용, 고생산 공정이 요구되고 있다. 이를 위해 인쇄전자 기술에 대한 연구가 활발히 진행되고 있다. 특히, 금속배선은 모든 소자의 기본이면서 낮은 저항과 높은 신뢰성을 동시에 요구하고 있어 인쇄전자 기술이 해결해야 할 가장 어려운 난제 중의 하나이다. 따라서 본 연구에서는 낮은 저항과 높은 신뢰성을 만족시킬 수 있는 새로운 금속배선 공정으로서 폴리이미드 필름을 초발수 처리한 후 친수 패턴을 하여 전도성 잉크에 함침함으로서 친수 패턴을 따라 금속배선이 이루어 지도록 하는 방법을 제안하고자 한다. 폴리이미드 필름의 표면을 플라즈마 처리하여 표면에 나노돌기를 형성시키고 불소기를 함유한 코팅층을 형성시킴으로써 물에 대한 접촉각이 $150^{\circ}$이상이 되도록 초발수 처리할 수 있었다. 초발수 처리된 폴리이미드 기판에 쉐도우 마스크를 사용하여 UV조사함으로써 조사된 부분만 친수성을 가지는 패턴을 형성하였다. 이렇게 친수 패턴이 제작된 초발수 폴리이미드 유연기판을 실버잉크에 함침함으로써 선폭 $200{\mu}m$를 가지는 금속배선을 형성시켰다. 형성된 금속배선의 단면 형상을 측정하였으며, 열처리를 통하여 비저항이 $30{\mu}{\Omega}$-cm를 얻을 수 있었다. 통상 1회의 함침으로는 금속배선의 두께가 150nm정도로 금속배선으로 사용하기에는 얇아 배선의 두께를 증가시키기 위하여 수 회 함침을 시도하여 $2{\mu}m$의 두께로 증가시킬 수 있었다. 이때 선폭과 선간 간격은 크게 변하지 않고 두께만 증가시킬 수 있었다. 이는 금속배선을 형성한 후에도 폴리이미드 유연기판의 초발수성은 그대로 유지되어 여러번 함침할 때 잉크가 이미 형성된 배선에만 묻게 되어 두께는 증가하나 선폭과 선간 간격은 증가하지 않는 것으로 판단된다. 사용한 실버잉크는 실버의 함량은 10~20wt%인 수계 잉크였다.

• Journal of the Korean Chemical Society
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• v.30 no.5
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• pp.449-455
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• 1986

Various polymer metal complexes have been synthesized from anhydrous $AlCl_3,\;FeCl_3,\;SbCl_5,\;SnCl_4\;and\;ZnCl_2$ with cation exchange resin in carbon disulfide solvent. The forms of the surfaces and sectioned beads of these polymer metal complexes have been observed using scanning electron probe microanalyzer. To examine the catalytic activity of polymer metal complexes, the esterification of various dibasic acids with alcohols have been carried out. Polymer metal complexes were found to be the effective catalyst for esterification of dibasic carboxylic acids.

• Journal of the Korean Chemical Society
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• v.34 no.5
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• pp.430-437
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• 1990

Various tris (${\eta}^4$-diene) molybdenums were easily synthesized by the reaction of various 1,3-dienes and molybdenum metal vapors by using metal atom reactor. The methyl substituent effect of the tris (${\eta}^4$-diene) molybdenum produced were discussed. And some alkadiene-molybdenum complexes which were easily decomposed in the air at room temperature were also formed.(C$_6$H$_{10}$)$_2$(CO)$_3$Mo were synthesized and its molybdenum-diene bond type were discussed.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.459-466
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• 2007

In this study, H-type beta zeolites (BEA) having various metals were used as the adsorbent for the removal of sulfur containing odorants. The different adsorbents containing single or bimetals were utilized to investigate the performance in the individual adsorption of TBM and THT odorants or in the competitive adsorption between them by using a continuous adsorptive bed system. The result shows that the pure H-type BEA zeolite exhibited the highest adsorption capacity for TBM compound, but the higher amount of THT was removed and adsorbed on a HBEA adsorbent having Fe, Pd metal and ZnO oxide. In the case of bimetal containing adsorbents, Cu-Zn/HBEA and Fe-Mo/HBEA showed a higher adsorption capacity for TBM.

• KSBB Journal
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• v.8 no.4
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• pp.370-374
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• 1993

In transportation the amount of metal ion by crown ethers, dibenzo-18-crown-6 were investigated using ultraviolet spectrometer. Transported the amount of one valence metal ion as $K^+ and Li^+}$ was not so much. On the other hand, two valence metal ion increased by dibenzo-18-crown-6, which means that the ionic charge and hydration of two valence metal ion affected the carrying ability of crown ethers. The carrying ability of dibenzo-18-crown-6 was, therefore, adequate for two valence metal ion as $Ca^{2+}$ and $Ba^{2+}$. It was also suggested that transport metal ion by crown ethers, which is related rather the catching ability than the selectivity of metalion.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.4
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• pp.247-254
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• 2012

Vitrification technology has been widely applied as one of effective processing methods for wastes generated in nuclear power plants. The advantage of vitrifying for low- and intermediate-level radioactive wastes has a large volume reduction and good durability for the final products. Recently, a filter using on HVAC(Heating Ventilating & Air Conditioning System) is composed with media (glass fiber) and separator (aluminum film) has been studied the proper treatment technology for meeting the waste disposal requirement. Present paper is a feasibility study for the filter vitrification that developing of the glass compositions for filter melting and melting test for physicochemical characteristic evaluation. The aluminum metal of film type is preparing with 0.5 cm size for proper mixing with glass frit, glass fiber is also preparing with 1 cm size within crucible. The glass compositions should be developed considering molten glass are related with wastes reduction. Glass compositions obtained from developing on glass formulation are mainly composed of $SiO_2$ and $B_2O_3$ for aluminum metal. A variety of factors obtained from the glass formulation and melting test are reviewed, which is feeding rate and glass characteristics of final products such as durability for implementing the wastes disposal requirement.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.204-215
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• 1993

Epoxy-activated chitin was synthesized by the reaction of epichlorohydrin with chitin which was isolated from waste marine sources such as crab shell. Followed by the reaction of epoxy-activated chitin with hexamethylenediamine, the aminohexyl chitin was synthesized. The aminohexyl chitin was subsequently reacted with epichlorohydrin to prepare the epoxy-activated aminohexyl chitin. Finally, the tannin-immobilized chitin (Resin I) was synthsized by the reaction of tannin solution with epoxy-activated aminohexyl chitin. Using silane coupling agent, the tannin-immobilized chitosan(Resin II) was synthesized by the reaction of $\gamma$-glycidoxypropyltrimethoxy silane with chitosan which was prepared by the deacetylation of chitin. Upon the pH variation, adsorptivities of these immobilized tannins to the metal ions such as $Cu^{+2}$, $Ni^{+2}$, $Cr^{+6}$, $Co^{+2}$, $Ca^{+2}$, $Pb^{+2}$, $Ba^{+2}$, and $UO_2{^{+2}}$ ions were determined by batch method. The adsorptivity tendencies of these immobilized tannin to the most of metallic ions were increased with pH. Furthermore, the adsorptivities of Resin(I) and Resin(II) upon the variation of pH, contact time, amount of resin and concentration of metal ion were investigated. As a result, it was found that these immobilized tannin on both chitin and chitosan showed good adsorptivities for uranyl ion.