• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2005년도 제13회 산화철워크샵
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• pp.47-58
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• 2005

산화철의 국제동향에 대하여 각 지역간의 수출입동향과 최근에 급속하게 성장하고 있는 중국의 산화철업계 동향에 대하여 소개하였다. 특히 세계 산화철 교역량은 산화철업계의 기술발전과 각국이 처한 환경에 따라 변화하며, 산화철의 주요용도중 하나인 안료용도의 경우 건축경기에 큰 영향을 받는다. 중국의 산화철업계는 전반적으로 크게 성장한 반면 다국적 기업의 진출에 따른 기술력 향상과 반대급부로 경쟁력 약한 중국내 기업정리등이 수반되었다. 산화철산업의 발전을 위하여는 타소재와의 가격경쟁력도 중요하지만 새로운 응용분야의개척이 필요하다. 본기술자료에서는 최근에 관심이 집중되는 산화철 나노분말에 대하여 신용도 및 특성에 대하여 소개하였다.

• Nuclear Engineering and Technology
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• 제56권3호
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• pp.941-948
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• 2024

The effects of radiation on the corrosion of canister materials were investigated for the reliable disposal of high-level radioactive waste. The test specimens were gamma-irradiated at a very low dose rate of approximately 0.1 Gy/h for six and twelve months. The copper and cast iron species were less corroded when irradiated. It is hypothesized that gamma rays suppress the formation of lower-enthalpy species like metal oxides and activate reductive reactions. In contrast, it was difficult to evaluate the effect of radiation on the corrosion of titanium and stainless steel.

• Corrosion Science and Technology
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• 제11권3호
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• pp.82-88
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• 2012

The thickness and chemical composition of oxides on heat recovery steam generator tubes of combined cycle power plant were examined in order to evaluate the corrosion of the tubes. Tubes were removed from the plant after actual operations for 21,482, 42,552 and 56,123 hours respectively. Thickness and growth rate of the oxide scale on reheater inner tube (SA213-T22) were very high compared to those other tubes. The oxide scale was about $250{\mu}m$ thick and uniform. The components of the scale were iron oxides. The oxide scale was mixed oxides consisting of magnetite$(Fe_3O_4)$ and hematite$(Fe_2O_3)$. The oxide on inner tube was removed using many kinds of chemicals and it was found that chelating agents were dissolved faster than other chemicals.

• 한국표면공학회지
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• 제31권2호
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• pp.101-108
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• 1998

The effect of oxidation-reduction heating conditions on coating adherence of hot-dip galvanized steel containing silicon has beeninvestigated. The presence of a stbke sillicon oxide formed on the steel surface has been shown to be very detrimenal to proper wetting by liquid zinc. When the steel has more than the critical sillicon content neeled to from a stable external oxide, the use of oxidation-reduction method has been found successful in obtaining a good quality, coated product with excellence adhreence. This can be explained by the formation of an iron oxide. The iron oxrtion of the scale is reduced, leaving the stable oxides dispersed in a fresh metallic iron surface layer. This reduced iron surface is easily wetted by the liquid zinc and excellent adherence is obtained.

• Journal of Applied Biological Chemistry
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• 제65권4호
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• pp.457-462
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• 2022

망간은 다양한 산화수로 존재하며 Mn(II)은 망간 중 가장 이동성이 높은 종으로 식물에 독성을 미치며 성장을 제한한다. 따라서, 본 연구의 목적은 다양한 흡착제를 이용하여 망간을 안정화함으로써 망간의 독성을 저감시키는 것이다. Ferrihydrite, schwertmannite, goethite를 합성하여 XRD로 확인하였고 망간 흡착에 사용하였다. Hematite는 구매하여 망간 흡착제로 사용하였다. CaNO₃, CaSO₄, CaCO₃와 같은 칼슘 화합물은 pH를 높이고 망간을 산화시키기 위해 사용하였다. 망간의 흡착을 위해 다양한 농도의 Mn(II) 용액을 4가지 철산화물, CaNO₃, CaSO₄, CaCO₃와 24시간 반응시킨 후 여과하여 용액에 남아있는 망간 농도를 ICP-OES로 분석하고 망간의 흡착율과 흡착등온식을 계산하였다. 그 결과, 철 산화물 중에서는 hematite에 의한 망간 흡착율이 가장 높았으며 ferrihydrite가 다음으로 흡착율이 높았다. 칼슘 화합물의 경우 CaCO₃>CaNO₃>CaSO₄ 순으로 흡착율이 높았다. CaCO₃은 hematite보다 높은 흡착율을 보였고 CaCO₃를 처리하면 pH를 증가시켜 망간의 독성을 감소하는 데 가장 효과적일 것으로 판단된다.

• Journal of Applied Biological Chemistry
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• 제50권1호
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• pp.6-12
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• 2007

Feasibility of laboratory-synthesized zerovalent iron was investigated to remove arsenic from leachates of tailings taken from an Au-Ag abandoned mine. The tailings were seriously contaminated with arsenic, and its potential adverse effect on the ecosystems around the mine seems to be significantly high. Long-term column experiments were conducted for about 3.5 months to evaluate the effectiveness of the synthesized zerovalent iron for removal of arsenic. Over than 95% removal efficiency of As was observed in the zerovalent iron mediated tests. In addition, the XRD data suggest that the corrosion products of ZVI were identified magnetite, maghemite, goethite, and lepidocrocite, all of which support Fe(II) oxidation as an intermediate step in the zerovalent iron corrosion process. The results indicate that arsenic can be removed from the tailing-leachate by the mechanism of coprecipitation and/or adsorption onto those iron oxides formed from ZVI corrosion.

• 자원환경지질
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• 제43권6호
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• pp.543-553
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• 2010

이 연구는 부여 정동리 꿩바윗골 유적에서 출토된 백제시대 경작토양의 광물학적 및 지구화학적 특정을 조사하고, 이를 사용하여 제작한 것으로 추정되는 무령왕릉 및 송산리 전(벽돌)과 토양을 비교하여 태토로서의 가능성을 검토하였다. 연구대상 토양시료들은 모두 미사질 양토로 가장 하부층을 제외하고는 모두 유사한 토양입도를 가지고 있다. 토양은 산성으로 일부 시료에서 유기물, P, S 등의 집적현상이 나타났다. 또한 지구화학적 원소 분포경향이 유사하며 석영, 사장석, 정장석, 질석, 운모, 고령석 등으로 구성되어 동일한 광물조성을 보인다. 부분적으로 붉은 철산화물의 농집이 관찰되는데, 강의 범람과 배수에 따른 산화와 환원환경이 반복되었던 환경이 토양 내 철산화물의 농집을 일으킨것으로 보인다. 이는 자연현상과 인간의 경작활동에 의한 풍화양상으로 볼 수 있다. 특히 무령왕릉과 송산리고분군 출토 전에서 발견되는 철산화물의 농집현상은 연구지역 토양이 전의 태도로 추정될 수 있는 추가적인 증거로 판단된다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.108.2-108.2
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• 2008

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.1-1
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• 2011

We developed a new generalized synthetic procedure, called as "heat-up process," to produce uniform-sized nanocrystals of many transition metals and oxides without a size selection process. We were able to synthesize uniform magnetite nanocrystals as much as 1 kilogram-scale from the thermolysis of Fe-oleate complex. Clever combination of different nanoscale materials will lead to the development of multifunctional nano-biomedical platforms for simultaneous targeted delivery, fast diagnosis, and efficient therapy. In this presentation, I would like to present some of our group's recent results on the designed fabrication of multifunctional nanostructured materials based on uniform-sized magnetite nanoparticles and their medical applications. Uniform ultrasmall iron oxide nanoparticles of <3 nm were synthesized by thermal decomposition of iron-oleate complex in the presence of oleyl alcohol. These ultrasmall iron oxide nanoparticles exhibited good T1 contrast effect. In in vivo T1 weighted blood pool magnetic resonance imaging (MRI), iron oxide nanoparticles showed longer circulation time than commercial gadolinium complex, enabling high resolution imaging. We used 80 nm-sized ferrimagnetic iron oxide nanocrystals for T2 MRI contrast agent for tracking transplanted pancreatic islet cells and single-cell MR imaging. We reported on the fabrication of monodisperse magnetite nanoparticles immobilized with uniform pore-sized mesoporous silica spheres for simultaneous MRI, fluorescence imaging, and drug delivery. We synthesized hollow magnetite nanocapsules and used them for both the MRI contrast agent and magnetic guided drug delivery vehicle.

• 한국분말재료학회지
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• 제20권3호
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• pp.174-179
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• 2013

The study on the fabrication of iron powder from forging scales using hydrogen gas has been conducted on the effect of hydrogen partial pressure, temperature, and reactive time. The mechanism for the reduction of iron oxides was proposed with various steps, and it was found that reduction pattern might be different depending on temperature. The iron content in the scale and reduction ratio of oxygen were both increased with increasing reactive time at 0.1atm of hydrogen partial pressure. On the other hand, for over 30 minutes at 0.5 atm of hydrogen partial pressure, the values were found to be almost same. In the long run, iron metallic powder was obtained with over 90% of iron content and an average size of its powder was observed to be about $100{\mu}m$.