• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 1993년도 EARTH 발표논문초록
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• pp.3.1-3
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• 1993

• Molecules and Cells
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• 제40권12호
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• pp.976-985
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• 2017

Iron is an essential divalent ion for aerobic life. Life has evolved to maintain iron homeostasis for normal cellular and physiological functions and therefore imbalances in iron levels exert a wide range of consequences. Responses to iron dysregulation in blood development, however, remain elusive. Here, we found that iron homeostasis is critical for differentiation of Drosophila blood cells in the larval hematopoietic organ, called the lymph gland. Supplementation of an iron chelator, bathophenanthroline disulfate (BPS) results in an excessive differentiation of the crystal cell in the lymph gland. This phenotype is recapitulated by loss of Fer1HCH in the intestine, indicating that reduced levels of systemic iron enhances crystal cell differentiation. Detailed analysis of Fer1HCH-tagged-GFP revealed that Fer1HCH is also expressed in the hematopoietic systems. Lastly, blocking Fer1HCH expression in the mature blood cells showed marked increase in the blood differentiation of both crystal cells and plasmatocytes. Thus, our work suggests a relevance of systemic and local iron homeostasis in blood differentiation, prompting further investigation of molecular mechanisms underlying iron regulation and cell fate determination in the hematopoietic system.

• 한국세라믹학회지
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• 제22권6호
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• pp.87-93
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• 1985

The hematite the magetite and the maghemite thin film were prepared by oxidation and reductino of the vaccum-evaporated iron thin film. Interre;atoms between film preparation process and the electrical properties were investigated. At room temperature the electrical conductivity of the iron the hematite the magnetite and the maghemite thin film were $1{\times}10^4\Omega^{-1}cm^{-1}$, 2{\times}10^{-5}\Omega^{-1}cm^{-1}$, $3{\times}10^{-5}\Omega^{-1}cm^{-1}$, and $4{\times}10^{-5}\Omega^{-1}cm^{-1}$, resp-ectively. The surface of each thin film was dense and homogeneous. At the temperature that the iron thin film was converted into the hematite thin film the electrical conductivity decreased rapidly and the electrical con-ductivity of the hematite thin film increased as temperature increased. The hematite thin film was reduced to the magnetite thin film in H2 atmosphere. The electrical conductivity decreased rapidly at the temperature that the maghemite thin film is formed by oxidation of the magnetite thin film and the electrical conductivity of the maghemite thin film increased as temperature increased.

• Journal of Nutrition and Health
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• 제28권10호
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• pp.986-994
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• 1995

This study was to examine the effect of phytate on the protein digestibility and calcium, iron and zinc availability in phytase treated soymilks digested with pepsin and pepsin-pancreatin in vitro. Also, the bending between phytate and protein in soymilks was investigated by means of SDS-PAGE. The content of phytate in soymilk was reduced by phytase treatment. As the content of phytate decreased, the protein digestibility increased in soymilk treated with the digest enzymes in vitro. The reduction of phytate content in soymilk improved the availability of all calcium, iron and zinc. Although the availability of calcium increased, the amount of change was small. The phytate reduction increased most the availability of iron. A number of bands of high molecular weight protein in soymilk disappleared in SDS-PAGE by lowering the phytate content with phytase treatement on soymilk.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.377-378
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• 2009

본 연구는 산업부산물인 황산철을 이용하여 컬러 모르터의 기초적인 물성을 평가하고자 하였다. 먼저, 굳지않은 모르터의 특성으로 황산철을 첨가할수록 플로우, 공기량 및 단위용적절량은 감소하는 것으로 나타났고, 압축강도는 황산철 6%치환에서 가장 증가한 것으로 나타났다.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권4호
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• pp.299-305
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• 2005

The work described in this paper is to investigate the additional iron losses and consequent temperatures in core ends of a turbo-generator wound with high voltage cables. Electromagnetic calculations are made with 3D FE models, which include the lamination material with anisotropic properties both in magnetic permeability and electric conductivity. The models also include the geometry of the stator teeth and eventually the axial steps designated to reduce the core end losses. The 3D model of the rotor consists of field windings with straight in-slot parts and end windings. The thermal models are simplified into two dimensions and include the heat sources dumped from the 3D electromagnetic solutions. The influences of power factor on additional iron losses are studied for this cable wound machine and conventional machines. The calculation results show that the additional iron losses can be reduced to about $15\%$ by introducing some small steps around the airgap corner of core ends.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.138-140
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• 2002

This paper deals with an automatic design procedure for the minimization of iron core loss in a synchronous reluctance motor (SynRM). The focus of this paper is the design relative to hysteresis loss on the basis of rotor shape of a SynRM in the same torque density. The coupled Finite Elements Analysis (FEA) & Preisach model have been used to evaluate the iron core loss with the rotor shape. The proposed procedure allows to define the rotor geometric dimensions starting from an existing motor or a preliminary design. The iron loss has been reduced with a rotor design variation.

• 한국연초학회지
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• 제8권2호
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• pp.29-41
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• 1986

Effects of some mineral nutrients on the chlorine absorption by the plants, on the chemical constituents and physical properties of leaves were investigated tinder the paddy field and pot conditions. The chlorine content of cured leaf grown in paddy field was high in iron and manganese application groups and highest in combined application of iron and manganese. Lime application inhibited the absorption of chlorine and increased the yield and quality of cured leaf, and inhibited the absorption of iron and manganese those causing the grey leaf. Lime application reduced the leaf chlorine content and rate of muddy grey leaf by increasing the soil pH in acid soil.

• 대한화학회지
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• 제54권1호
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• pp.131-136
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• 2010

다양한 철 원소의 조성을 갖는 인산알루미늄 철을 합성하여 표면 성질과 벌크 성질을 조사하였다. 벤질 알코올과 디에틸 말론산의 transesterification반응에 의해 촉매 특성을 결정 하였다. 에틸 벤질 말론산과 디벤질 말론산을 유일한 생성물로 얻었다. 철 성분이 0.025 몰 퍼센트인 FeAlP의 경우에 특이한 촉매 특성과 조직상의 특성이 나타난다. 디에스터의 형성은 중간 정도 크기의 산성 자리에서 이루어진다. 물질 안에 수화된 알루미나와 polycondensed인산이 존재할 경우에는 에스터교환 반응에서 인산 알루미늄 철의 촉매 특성이 감소하게 된다.

• Environmental Engineering Research
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• 제20권3호
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• pp.205-211
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• 2015

Reduced forms of iron, such as zero-valent ion (ZVI) and ferrous ion (Fe[II]), can activate dissolved oxygen in water into reactive oxidants capable of oxidative water treatment. The corrosion of ZVI (or the oxidation of (Fe[II]) forms a hydrogen peroxide ($H_2O_2$) intermediate and the subsequent Fenton reaction generates reactive oxidants such as hydroxyl radical ($^{\bullet}OH$) and ferryl ion (Fe[IV]). However, the production of reactive oxidants is limited by multiple factors that restrict the electron transfer from iron to oxygen or that lead the reaction of $H_2O_2$ to undesired pathways. Several efforts have been made to enhance the production of reactive oxidants by iron-induced oxygen activation, such as the use of iron-chelating agents, electron-shuttles, and surface modification on ZVI. This article reviews the chemistry of oxygen activation by ZVI and Fe(II) and its application in oxidative degradation of organic contaminants. Also discussed are the issues which require further investigation to better understand the chemistry and develop practical environmental technologies.