• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.807-810
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• 2008

Permeable reactive barriers containing Zero-valent iron (ZVI) are used to purify ground-water contaminants. One of the representative contaminant is trichloroethylene (TCE). ZVI can act as a reducing agent of TCE. When ZVI is oxidized to Ferric iron, TCE reduced to Ethene, which is non-harmful matter. As a ZVI becomes ferric iron, the reducing effect decreases and iron becomes unavailable. So, constant reduction of TCE requires the regular supply of reducing agent. So, we use Iron-reducing bacteria(IRB) to extend the TCE degrading ability. We perform three experiment DI water, DI water with medium, and DI water with medium and IRB. By the experiment we try to found the dissolve ability.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.218-225
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• 2007

A lactic acid bacterium capable of anaerobic respiration was isolated from soil with ferric iron-containing glucose basal medium and identified as L. garvieae by using 16S rDNA sequence homology. The isolate reduced ferric iron, nitrate, and fumarate to ferrous iron, nitrite, and succinate, respectively, under anaerobic $N_2$ atmosphere. Growth of the isolate was increased about 30-39% in glucose basal medium containing nitrate and fumarate, but not in the medium containing ferric iron. Specifically, metabolic reduction of nitrate and fumarate is thought to be controlled by the specific genes fnr, encoding FNR-like protein, and nir, regulating fumarate-nitrate reductase. Reduction activity of ferric iron by the isolate was estimated physiologically, enzymologically, and electrochemically. The results obtained led us to propose that the isolate metabolized nitrate and fumarate as an electron acceptor and has specific enzymes capable of reducing ferric iron in coupling with anaerobic respiration.

• Journal of Life Science
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• v.20 no.11
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• pp.1611-1616
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• 2010

The purpose of this research was to determine the effect of surfactant micelles on lipid oxidation in W/O/W multiple emulsions. The content of ferric irons and hydroperoxide in the continuous phase in W/O/W multiple emulsions was measured as a function of Brij micelle. The concentration of ferric iron and hydroperoxide in the continuous phase increased with increased storage time (1~6 days). Lipid oxidation rates, as determined by the formation of lipid hydroperoxides, TBARs and headspace hexanal, in the W/O/W multiple emulsions containing ferric iron decreased when 3% surfactant micelles were exceeded. These results indicate that excess surfactant micelles could alter the physical location and prooxidant activity of iron in W/O/W multiple emulsions.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.496-501
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• 2005

The thermal degradation of ABS in the presence of iron-based metal catalysts has been studied by thermogravimetric analysis (TGA). The reaction of iron-based metal catalysts (ferric nitrate nonahydrate, ammonium ferric sulfate dodecahydrate, iron sulfate hydrate, ammonium ferric oxalate, iron(II) acetate, iron(II) acetylacetonate and ferric chloride) with ABS has been found to occur during the thermal degradation of ABS. In a nitrogen atmosphere, char formation was observed, and at $600^{\circ}C$ approximately 3~23 wt% of the reaction product was non-volatile char. The resulting enhancement of char formation in a nitrogen atmosphere has been primarily due to the catalytic crosslinking effect of iron-based metal catalysts. On the other hand, char formation of ABS in air at high temperature by iron-based metal catalyst was unsuccessful due to the oxidative degradation of the char.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.770-774
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• 2002

Effect of surfactant micelles on lipid oxidation was determined in soybean oil-in-water (O/W) emulsions. The concentration of ferric irons to continuous phase in the O/W emulsions was measured as a function of various Brij type and concentrations. The concentration of ferric iron in the continuous phase increased with increasing surfactant micelles concentration $(0.5{\sim}2.0%)$ and storage time $(1{\sim}7\;days)$. At pH 3.0, the concentration of continuous phase iron was higher than at pH 7.0. Lipid oxidation rates, as determined by the formation of lipid hydroperoxides and headspace hexanal, in the O/W emulsions containing ferric iron decreased with increasing surfactant micelle concentration $(0.5{\sim}2.0%)$. These results indicate that surfactant micelles concentration could alter the physical location and prooxidant activity of iron in soybean O/W emulsions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.755-759
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• 1999

To evaluate the effect of sterilizing method on the quality of iron fortified market milk, HTST(high temperature, short time) or LTLT(low temperture, long time) method was adopted after addition of 100ppm ferrous sulfate, ferric citrate, ferric ammonium citrate, or ferrous lactate in market milk. Sterilized iron fortified market milk was stored at 4oC and then pH, lipid oxidation, color change, and sensory quality were observed. The range of pH change in iron fortified market milk sterilized by HTST or LTLT was 6.51~6.74. The order of pH was control>ferric ammonium citrate>ferrous lactate>ferrous sulfate>ferric citrate. Oxygen consumption of ferric ammonium citrate and ferric citrate was lower than ferrous lactate and ferrous sulfate. This trend was same in HTST and LTLT method, but generally oxygen consumption was lower in iron fortified market milk sterilized by LTLT method than by HTST. In total color change, ferrous lactate treatment was closer to control than other treatments. Also sensory characteristics of ferrous lactate treatment was showed better quality than other treatment. From these results, LTLT method was more suitable than HTST method for iron fortified market milk and ferrous lactate was comparably suitable among iron salts used in this study.

• Preventive Nutrition and Food Science
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• v.3 no.1
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• pp.1-9
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• 1998

Studies were performed to 1) investigate if ferric iron bound in complex with iron-solubilizing meat components is absorbable, 2) compare the relative iron-solubilizing capaicty of meats, and 3) investigate the physicochemical and compositional characteristics if meat meat has iron-solubilizing components . Iron-solubilizing components of beef were isolate from pH 2 HCL homogenates into dialysis bags(MWCO of 6-8K). Radiolabelled iron complexes were then generated using ferric iron and the isolated low-molecular-weight components(ILC) from undigested beef or ascrobate. The bioavailabilities of radioiron in these complexes or as ferric iron were measured as radioiron absorption into the blood one hour after injection into ligated duodenal lops of rats. Iron absorptions were ferrous -ascorbate complexes(18.8$\pm$2.2%)> ferric-ILC complexes(4.9$\pm$0.6%)>ferric iron (23.2$\pm$0.3%)(p<0.05). ILC from 0.1g of beef, pork, chicken, fish , or egg white were added to 400$\mu$g ferric iron in pH 2 HCL, the pH raised to 7,2, and soluble iron determined in the supernatant after centrifugation at 2,500g for 10 min. Iron solubilizing capabilities of ILC were pork (99.9$\pm$0.1%)>beef(93.6$\pm$3.5%)> chicken (75.8$\pm$1.8%) > fish(64.6%$\pm$3.6%)>egg white(50.9$\pm$0.9%)(p<0.05). The compositional and physico-chemical characteristics of the ILC from the above dietary protein sources were investigated.

• Journal of the Mineralogical Society of Korea
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• v.24 no.3
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• pp.189-194
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• 2011

Martian satellite missions indicate that Martian equatorial plains are covered by ferric iron oxide. As a non-destructive technique, low-temperature treatment of remanent magnetization is effective in identifying magnetic minerals in rocks. In the present study, four sets of ferric iron oxides were prepared by aqueous alteration of ferrihydrite at warm conditions and four others by dehydration of goethite. As the amount of aluminous trivalent cations increases, crystallographic lattice parameters and N$\acute{e}$el temperatures decrease. Such declines originate from lattice distortion as the smaller aluminous trivalent cations substitue the larger terric irons. Whilst high remanence memory was observed for aqueously produced ferric iron oxide, low remanence memory was observed for dehydrated ferric iron oxide. In the future. magnetic remanence memory would be powerful in diagnosing the origin of ferric iron oxide.

• Journal of the Korean Ceramic Society
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• v.35 no.3
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• pp.239-244
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• 1998

Iron complexes were prepared using ferric nitrate and ethylene glycol as starting materials and the ul-trafine ${\alpha}-Fe_2O_3$ particles with the sizes smaller than 200nm were obtained by the pyrolysis of iron com-plexes at over $350^{\circ}C$ In addition the decomposition mechanism of the synthesized iron complexes was in-vestigated by differential scanning calorimeter X-ray diffractometer and IR spectrometer. Transmission electron microscopy and BET method were performed to analyze the effects of ferric nitrate contents and reaction temperatures on the size and shape of the particles.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.705-709
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• 1999

To evaluate iron bioavailability in iron fortified milk, in vitro and in vivo method were used. Low molecular weight components(ILC) from milk was isolated and iron was added, then soluble iron from ILC iron complex was determined. Each iron sources and extrinsically labelled with FeCl3 was used for measuring absorption rate of iron from ILC radiolabelled iron complexes as radioiron absorption into the blood one hour after injection into ligated duodenal loops of iron deficient rats. Iron absorption rate was in the order of ferrous lactate(25.56%)$\geq$ferric citrate(24.71%)$\geq$ferrous sulfate(19.67%) when 100ppm iron was used. In separate experiments, iron fortified milks with each iron sources were gavaged into iron deficient rats. When 25ppm iron was added to milk, the order of iron absorption was ferrous sulfate(12.52%)>ferrous lactate(8.07%)>ferric citrate(6.52%) (p<0.05). When 100ppm iron was added to milk, absorption rate was decreased compared to the treatments with added 25ppm of iron. Absorption rate of ferrous sulfate(5.34%) from milk added 100ppm iron was highly lowered, but ferric citrate(6.45%) was not significantly changed. The absorption rate of ferrous lactate(5.82%) was 70% of 25ppm iron added milk.