• 한국결정성장학회지
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• 제17권6호
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• pp.272-276
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• 2007

생산성이 우수한 스컬용융법(Skull melting method)에 의해 다양한 색의 보석용 큐빅지르코니아(Cubic Zirconia) 단결정을 성장시켰다. 큐빅지르코니아 단결정은 굴절률, 분산, 경도가 다이아몬드와 유사하고 3d 전이원소, 4f 희토류원소를 첨가하여 다양한 색개발이 가능하므로 합성보석으로 대표적이다. 첨가제로는 $Pr_6O_{11},\;TiO_2,\;MnO_2,\;Er_2O_3$를 2가지 이상적정 혼합하여 성장시켰고, 색향상과 균일성을 위해 열처리를 병행하였다. 본 연구는 천연 유색보석인 페리도트, 연수정, 적색 투어멀린의 색재현에 그 목적이 있다.

• 방사성폐기물학회지
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• 제15권2호
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• pp.181-189
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• 2017

방사성금속폐기물의 관리 옵션들을 안전성, 경제성, 작업자 피폭, 부피 감용 등의 선별 기준을 적용하여 비교 평가하였다. 원전 해체로부터 발생하는 금속폐기물의 관리 옵션에는 무구속 방출, 제한적 재사용, 그리고 직접 처분이 있다. 고려된 각각의 옵션들은 금속폐기물의 절단과 용융에 의한 부피감용을 수반한다. AHP기법을 적용하여 각 옵션들의 순위를 부여하였다. 방사성금속폐기물을 용융하여 금속 잉곳을 제조한 후 제한적 재이용 또는 무구속 방출하는 방안이 가장 효율적인 옵션으로 도출되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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• pp.48-52
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• 2003

Low melting crystalline solder glasses for CRT sealing were prepared from the composition of PbO 73.0~75.5 wt%, ZnO 12~15 wt%, $B_2O_3$ 7.0~9.0 wt%, BaO 1.5~3.5 wt%, $P_2O_5$ 1.0~2.5 wt%, $Bi_2O_3$ 0.5~20 wt%. The nucleation and crystallization of the crystalline solder glasses were studied by DTA, SEM and XRD. $2PbO{\cdot}ZnO{\cdot}B_2O_3$ crystalline phase was formed from glass matrix by heat-treatment of glass frits Crystalline solder glasses developed from this paper have good firing condition of $430{\sim}440^{\circ}C$ for 10min and good physical properties

• 한국재료학회지
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• 제16권6호
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• pp.351-354
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• 2006

[ $Co_{1-x}Fe_xSb_3$ ] skutterudites were synthesized by encapsulated induction melting and their thermoelectric properties were investigated. Single phase ${\delta}-CoSb_3$ was successfully obtained by the subsequent heat treatment at 773 K for 24 hours in vacuum. However, ${\delta}-CoSb_3$ was decomposed to FeSb2 and Sb when $x{\leq}0.3$, which means that the solubility limit of Fe to Co is x<0.3. The positive signs of Seebeck coefficients for all Fe-doped specimens revealed that Fe atoms acted as p-type dopants by substituting Co atoms. Thermoelectric properties were remarkably enhanced by Fe doping and optimum composition was found to be $Co_{0.7}Fe_{0.3}Sb_3$ in this study.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.686-687
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• 2006

The encapsulated induction melting and hot pressing were employed to prepare Fe-doped $CoSb_3$ skutterudites and their thermoelectric properties were investigated. Single phase $\delta-CoSb_3$ was successfully obtained by the subsequent heat treatment at 773K for 24 hours. Iron atoms acted as electron acceptors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by the appropriate doping. $Co_{0.7}Fe_{0.3}Sb_3$ was found as an optimum composition for best thermoelectric properties in this work.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.83-84
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• 2007

Sn-filled and Ni-doped $CoSb_3$ skutterudites were prepared by encapsulated induction melting, and their filling and doping effects on thermoelectric properties were investigated. Single phase ${\delta}-CoSb_3$ was successfully obtained by encapsulated induction melting and subsequent heat treatment at 823K for 5 days. Nickel atoms acted as electron donors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by Sn filling and Ni doping.

• 환경위생공학
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• 제22권1호
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• pp.1-16
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• 2007

The incineration process has commonly used for wastes amount reduction and thermal treatments of pollutants as the technologies accumulated. However, the process is getting negative public images owing to matter of hazardous pollutants emission. Specially dioxins became a main issue and is mostly emitted from municipal solid wastes incineration. In this reason, pyrolysis/gasfication/melting process is presented as a alternative of incineration process. The pyrolysis/gasfication/melting process, a novel technology, is middle of verification of commercial plant and development of technologies in Korea. But the survey about the pollutant emission from the process, and background data in these facilities is necessary. So in this survey, it Is investigated that the behavior of dioxins in three pyrolysis/gasfication/melting plant (S, T, P) of pilot scale. In case of S plant, concentration of dioxins shows high at latter part of cogenerated boiler and stack which are operate on low temperature conditions than a latter parts of pyrolysis and melting furnace which are operate on high temperature condition. Concentration of gas phage dioxins had increased after combusted gas passed cogenerated boiler and this is attributed to react of precursor materials such as chlorobenzene and chlorophenol. Concentration of dioxins in T plant showed lower levels at latter part of cooling equipment which are operate with water spray type on low temperature conditions than a latter parts of gasfied melting furnace which are operate on high temperature condition. Removal efficiency of dioxins at gas treatment equipment was 78.8 %. Concentration of dioxins in P plant was low at latter part of SDA/BF which is operate at low temperature conditions than a latter parts of pyrolysis gasfied chamber which are operate at high temperature condition. Removal efficiency of dioxins of SDA/BF was 85.9 % and therefore, it showed high efficiency at those of stoker type incineration facility. However, concentration of dioxins which emitted at high temperature condition were low in three facilities and satisfied present standard emission level of dioxins. To consider the distribution ratio of dioxins, Particulate phase dioxins at S and P plants showed similar ratio with which shows in current stoker type for middle scale domestic waste incineration facility. It is necessary to continuos monitoring the ratio of distribution of dioxins in T plant in because ratio of gas phage dioxins showed high.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2005년도 추계정기총회 및 제26회 학술발표대회 고분자리싸이클링기술 특별심포지엄
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• pp.251-255
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• 2005

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 추계학술논문요약집
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• pp.323-324
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• 2018

• 열처리공학회지
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• 제14권3호
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• pp.151-154
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• 2001

$TiO_2$ thin film has wide application because of its high capacitanca, reflection, and good transmissivity in visible range. $TiO_2$ thin film can be made by thermal deposition method, reactive evaporation method, activated reactive evaporation(ARE) method. In the case of thermal deposition, the oxygen deficiency can occur because the melting point of Ti is very high. While in the case of reactive evaporation, high density $TiO_2$ can not be made, because reactive gas($O_2$) and evaporated material(Ti) are not fully combined, activated reactive evaporation, $TiO_2$ is easily deposited at lower gas pressure compared with reactive evaporation because the ionized reactive gas is made by plasma. Therefore, activated reactive evaporation is very useful to deposit the material having the high melting point. In this work, we formed $TiO_2$ thin film by activated reactive evaporation method. The surface of $TiO_2$ thin film was analyzed by X-ray photoelectron spectroscopy. The surface morphology which was analyzed by atomic force microscopy(AFM) shows that feature of the film surface is uniform. The dielectric capacitance, withstanding voltage were $600{\mu}F/cm^2$, 0.4V respectively. In further work, we can increase the withstanding voltage by improving the deposition parameter of substrates.