• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.191-192
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• 2008

본 연구에서는 침수식물이 습지의 생지화학적 환경에 미치는 영향을 조사하고자 하였다. 침수식물이 없는 대조군보다 침수식물이 밀생한 습지반응조에서 수체내 용존산소의 농도 변화와 pH가 크게 나타나, 침수식물이 습지에서 수체와 저질의 산화-환원조건을 변화시켜, 질산화나 탈질과 관련된 습지의 생지화학적 반응에 영향을 줄 수 있음을 보여주었다.

• Defense and Technology
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• no.2 s.288
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• pp.60-67
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• 2003

높은 비강도와 산화성 및 환원성 분위기에서의 탁월한 내식성 등으로 무기체계에 적합한 소재인 타이타늄은 1790년 영국의 목사 Gregor가 원소를 발견한지 156년이 지난 1946년에서야 비로소 첫방탄시험이 미국의 실험실에서 이루어지게 되었다. 그러나 타이타늄의 높은 화학반응성과 높은 융점($1670^{\circ}C$)때문에 상업적으로 광범위하게 사용되는 것은 더디게 진행되어 왔다. 최근 선진국에서는 타이타늄 재료의 지상무기체계 적용이 광범위하게 검토되어 진행되고 있다.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.04a
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• pp.26-27
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• 1994

효소는 생체내의 합성, 분해, 산화, 환원 등 복잡한 화학반응이 상온, 상압, 중성부근에서 효율적으로 진행되게 하는 단백질이 주성분인 유기촉매이다. 현재 알려져 있는 효소의 종류는 수백만종 이상으로 추정되며 그 중 100여종 이상은 순수한 결정상태이며 약 600종 정도는 어느 정도 순수하게 징제되고 있다. 이들 효소의 분자량은 Ribonuclease의 12,700에서 부터 L-Glutamate dehydrogenase나 Carboxylase의 1,000,000 이상으로 광범위하다.

• Proceedings of the Materials Research Society of Korea Conference
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• 1996.11a
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• pp.11-11
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• 1996

• Journal of the Korean Chemical Society
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• v.27 no.5
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• pp.376-381
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• 1983

Dispersed nickel particles on Spherocarb were prepared at 540$^{\circ}C$ in various reaction atmosphere. Magnetic properties of these samples were determined, and results were compared with those of unsupported and MgO supported nickel particles. It was shown that nickel react primarily with carbon regardless of reducing atmosphere. In addition, apparent possibility of nickel-carbon interaction was discussed.

• Defense and Technology
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• no.3 s.289
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• pp.51-57
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• 2003

높은 비강도와 산화성 및 환원성 분위기에서의 탁월한 내식성 등으로 무기체계에 적합한 소재인 타이타늄은 1790년 영국의 목사 Gregor가 원소를 발견한지 156년이 지난 1946년에서야 비로소 첫방탄시험이 미국의 실험실에서 이루어지게 되었다. 그러나 타이타늄의 높은 화학반응성과 높은 융점($1670^{\circ}C$)때문에 상업적으로 광범위하게 사용되는 것은 더디게 진행되어 왔다. 최근 선진국에서는 타이타늄 재료의 지상무기체계 적용이 광범위하게 검토되어 진행되고 있다.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.191-196
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• 2006

The injection of ozone, produced by dielectric barrier discharge, into the exhaust gas gives rise to a rapid oxidation of NO that is the main component of nitrogen oxides($NO_x$) in most practical exhaust gases. Once NO is converted into $NO_2$, it on readily be reduced to $N_2$ in the next step by a reducing agent such as sodium sulfide and sodium sulfite. The reducing agents used ca also remove $SO_2$ effectively, which makes it possible to treat $NO_x\;and\;SO_2$ simultaneously. The present two-step process made up of an ozonizing chamber and an absorber containing a reducing agent solution was able to remove about 95% of the $NO_x$ and 100% of the $SO_2$, initially contained in the simulated exhaust gas. The formation of $H_2S$ from sodium sulfide was prevented by using a strong basic reagent(NaOH) together with the reducing agent. The removal of $NO_x$\;and\;SO_2$ was more effective for $Na_2S$ than $Na_2SO_3$.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.335-342
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• 2006

Metal aluminum, of which has a low standard reduction potential, participates in the electrochemical oxidation reaction and results in the structural change and accompanying property variation of aluminum and its oxide film. Aluminum was electrochemically etched in acid solution and the surface area was magnified by the formation of high density etch pits. Etched aluminum was covered with a compact and dense dielectric oxide film by anodization and applied to the capacitor electrode. Anodization of aluminum in acid solution at low temperature makes a nanoporous aluminum oxide layer which can be used for the fabrication template of nanostructural materials. Electrochemical characteristics of aluminum turn the metal aluminum into functional materials and it will bring the diverse applications of metal aluminum.

• Journal of Hydrogen and New Energy
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• v.16 no.1
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• pp.49-57
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• 2005

[ $MO/Al_2O_3-ZrO_2$ ](M=Ni and Cu) mixed metal oxides were prepared using sol-gel method in order to investigate the applicability to the 2-step thermo-chemical water splitting process and their redox behaviors were studied by temperature programmed reaction(TPR) from room temperature to 900$^{\circ}C$ under 5% $H_2$/Ar for the reduction and $H_2O$/Ar for the oxidation, respectively. From the results, peaks of the reduction and the oxidation on temperature were shifted with the change of crystalline phases due to the addition of $Al_2O_3$ and $ZrO_2$. The intensities of the peaks were also increased with the increase of contents of NiO or CuO that could be considered as active species. In addition, based on the observation of SEM images before and after the redox test, it seemed that $Al_2O_3-ZrO_2$ added prevented high temperature sintering of active metal components such as Ni (or Cu) on the surface and played a role of dispersing the active species homogeneously in solid solution of mixed oxides.

• Journal of Energy Engineering
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• v.15 no.2 s.46
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• pp.107-117
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• 2006

The status of water splitting thermochemical cycle for hydrogen production was reviewed in this article. Mass production of hydrogen could be possible using the thermochemical process which is similar to the concept of conventional chemical reaction system if the high temperature heat source is available. The mediators (chemicals and reagents) should be used to split chemically stable water, and should be recycled in a closed cycle in order to be environmentally acceptable. Though there is no process to reach commercial stage, IS cycle, two-step cycles based on metallic oxide such as ZnO/Zn, $Fe_3O_4/FeO$ and the associated cycles are attracted due to their possibilities of application. Development of materials for high temperature and/or corrosive conditions during thermochemical process is still important topic in some thermochemical processes.