• 상하수도학회지
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• 제26권6호
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• pp.779-786
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• 2012

The degradation of 2-chlorophenol(2-CP) by various AOPs(Advanced Oxidation Processes) including the photo-Fenton process has been examined. In sole $Fe^{2+}$, UV or $H_2O_2$ process without combination, low removal efficiencies have been achieved. But the photo-Fenton process showed higher removal efficiency for degradation of 2-chlorophenol than those of other AOPs including the Fenton process and the UV processes. In the photo-Fenton process, the optimal experimental conditions of 2-chlorophenol degradation were obtained at pH 3 and the $Fe^{2+}/H_2O_2$molar ratio of 1. Also the 2-chlorophenol removal efficiency increased with decreasing of the initial 2-chlorophenol concentration. 3-chlorocatechol and chlorohydroquinone were identified as photo-Fenton reaction intermediates, and a degradation pathway of 2-chlorophenol in the aqueous phase during the photo-Fenton reaction was proposed.

• 한국세라믹학회지
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• 제38권3호
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• pp.245-250
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• 2001

BaO-TiO$_2$계의 TiO$_2$-rich 조성영역에 대한 상평형 관계를 완전 고상 반응법을 통하여 재평가하였다. 출발 시료로는 이 계의 end-member인 BaO와 TiO$_2$(rutile)를 이용하였다. 각 시료들은 대기 중에서 800~120$0^{\circ}C$의 온도구간에서 선택적으로 열처리되었다. 열처리된 시편들은 상온까지 급냉 처리되었으며, 상 분석은 X-ray 회절 분석을 통하여 이루어졌다. 연구결과에서 BaTi$_2$O$_{5}$(1:2)상과 BaTi$_{5}$O$_{11}$(1:5)상이 저온에서의 고상 반응을 통해서도 쉽게 형성될 수 있음을 알 수 있었으며, 각 저온 상들의 불변 반응 온도를 열처리 온도에 따른 상 분석을 통하여 확인할 수 있었다.

• 대한기계학회논문집B
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• 제33권4호
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• pp.272-277
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• 2009

The liquid phase LPG injection (LPLi) system (the 3rd generation technology) has been considered as one of the most promising fuel supply systems for LPG vehicles. To investigate the reaction characteristics of LPG with rubber parts in LPLi system, various rubbers were tested. The results showed that the amount of residue from the cover rubber of a fuel pump was increased about 10 times after testing. Furthermore, the amount of sulfur and nitrogen species which are considered as main sources of deposit formation in LPLi fuel injectors were also found to be higher than those in original LPG fuel. In addition, these residues made the core parts of LPLi injector such as needle and nozzle, partially worn, which eventually causes leakage in LPLi injectors.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1157-1162
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• 2004

A well-holder type piezoelectric chloramphenicol (CAP) immunosensor which was prepared by binding an anti­CAP antibody to the chemisorbed monolayers of various thiol or sulfide compounds over the gold electrode surface of quartz crystals through a carboxyl-amine coupling procedure, using the activation with l-ethyl- 3-(3-dimethylarninopropyl)carbodiimide­HCl and N-hydroxysulfosuccinimide, was determined for its responses to CAP, CAP succinate, and water-soluble CAP. The reaction phase used in the well holder was 0.01 M phosphate buffer (pH 7.4), and the solvent for analyte dissolution varied according to the solubility of the individual analyte. The analyte detection which was indicated by a steady-state frequency shift was finished within 10 min, except for CAP dissolved in methanol. The responses of CAP succinate and water-soluble CAP in the reaction phase were very stable, while a minute fluctuation was found with CAP.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.123-126
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• 2001

Multiwalled carbon nanotubes were massively produced by the catalytic reaction of C$_2$H$_2$ - Fe(CO)$\sub$5/ mixture at 750 - 950$^{\circ}C$ in a quartz tube reactor and over quartz substrates. Well-aligned MWNT array grows perpendicular to the quartz tube reactor and the quartz substrates at an average of 60 nm in diameter and up to several thousands of micrometers in length. This method does not require any pretreatment of substrates and CNTs are grown at atmospheric pressure. It could be suitable for mass production of multiwalled nanotubes. Scanning electron microscope and transmission electron microscope images of the nanotubes deposited on the substrates allowed us to monitor the quality of MWNTs grown under different operating conditions.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.543-547
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• 2005

The Belousov-Zhabotinskii system measured by a Pt electrode is investigated under external electrode current constraint. A dynamical analysis of the electrode reaction phase has been made by means of a linearized stability criterion valid for three-variable system. It turns out that limit cycle oscillatory regime and dynamical behaviors of the electrode reaction phase have been degenerated under periodical electrode current.

• 한국세라믹학회지
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• 제43권1호
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• pp.28-32
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• 2006

Diarylethene in photochromic materials was doped in organic-inorganic hybrid low-melting glasses were synthesized through a nonaqueous acid-base reaction process, which consists of network units including a small number of bridging oxides. The organic phase is a dichlorodimethylsilane while the inorganic phase is a tin(II) chloride. Diarylethene was incorporated into the glasses without any degradation of its functionality. The open form of diarylenthene, which is converted from the opening one upon UV-irradiation, is change to the closed form visible light-irradiation. The rate constant of the photochemical reaction is $31.78\times10^{-3}s^{-1}$ with 400 W UV lamp irradiation.

• 한국세라믹학회지
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• 제34권11호
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• pp.1159-1164
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• 1997

Magnetite(Fe3O4) powders were synthesized through glycothermal reaction by using crystalline $\alpha$-FeOOH as precursor and ethyleanne glycol as solvent. The phase, morphology and particle size of synthesized powders were characterized by XRD and an SEM. When only ethylene glycol was used as solvent, the phase was transformed from $\alpha$-FeOOH to $\alpha$-Fe2O3 and finally Fe3O4 at 27$0^{\circ}C$ for 6hr without morphological change. But by addition of water, Fe3O4 powders were synthesized at 23$0^{\circ}C$ for 3hr through solution-recrystalization process. As the content of water addition increased, the particle shape changed from sphere to octahedron and the partcle size increased. When the excess amount of water added, residual $\alpha$-FeOOH or $\alpha$-Fe2O3 was recrystalized.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1085-1090
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• 1991

Chemical heat pump is a system to upgrade the low level energy such as industrial waste heat and solar energy by using coupled endothermic and exothermic chemical reactions. Dehydrogenation of 2-propanol can absorb heat near 80.deg. C and is transformed into acetone and hydrogen. Hydrogenation of acetone can liberate heat near 200.deg. C. Dehydrogenation of 2-propanol is difficult around 80.deg. C because .DELTA.G has positive value, but dehydrogenation reaction in liquid phase can overcome this problem because vaporized acetone and hydrogen can be rapidly eliminated. In this work, dehydrogenation of 2-propanol was investigated in liquid phase with Raney nickel catalyst. The energy efficiency of the chemical heat pump was estimated by computer simulation.

• 항공우주기술
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• 제11권1호
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• pp.145-157
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• 2012

상평면상에서 추력기를 사용하는 자세제어 시스템의 리밋 사이클을 해석하는 새로운 기법이 논문에 의해서 제안되었다. 그러나 이것은 소프트 시뮬레이션상에서 Haloulakos 방식보다 제안 방식이 정확함을 보였지만, 실제 시스템으로 검증하지는 못하였다. 그래서 저자의 제안 방식을 KSLV-I 추력기 자세제어 시스템에 대한 실시간 모의시험으로 검증하고, 리밋 사이클 해석에 대하여 실시간 모의시험 결과와 이론적으로 구한 값을 비교/분석하였다.