• Journal of Pharmaceutical Investigation
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• v.17 no.2
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• pp.79-88
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• 1987

In order to reduce gastric irritation of iron preparations, one prodrug, glycine complex of ferrous fumarate, was synthesized, identified, examined for physico-chemical properties and compared with ferrous fumarate, ferrous sulfate and ferroglycine sulfate. That novel ferroglycine fumarate (FGF) resulted in higher dissolution rate in water, artificial gastric and intestinal juice. The absorption rate constants $(K_a)$ in rat of FGF was greater and ulcerogenic dose on stomach was increased remarkably than those of iron parent materials and ferroglycine sulfate.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.4
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• pp.1-6
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• 2001

In the present industry, there are necessary to cut only iron metals but also non-ferrous metals such as aluminum, brass, plastic and wood(Paulownia), therefor it had been made the studies of non-ferrous metals by many scientists. we hope this kind of study will continue. The purpose of this study is to conduct the basic experiment about influencing of the feedrate adjustment and the change of the side rake angle at turning of non-feerous metals. As the results, the surface roughnesses were on the decrease with a side-rake angle and feedrate diminution in the case of the pastic, aluminum, and paulownia.

• Proceedings of the Korean Ceranic Society Conference
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• 2004.04b
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• pp.27.2-27.2
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• 2004

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.231-238
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• 2008

This study proposed the method of phosphate recovery from municipal wastewater by using ferrous iron waste, generated from the mechanical process in the steel industry. In the analysis of XRD, ferrous iron waste was composed of $Fe_3O_4$ (magnetite), practically with $Fe^{2+}$ and $Fe^{3+}$. It had inverse spinel structure. In order to identify the adsorption characteristic of phosphate on ferrous iron waste, isotherm adsorption test was designed. Experimental results were well analyzed by Freundlich and Langmuir isotherm theories. Empirical constants of all isotherms applied increased with alkalinity in the samples, ranging from 1.2 to 235 $CaCO_3/L$. In the regeneration test, empirical constants of Langmuir isotherm, i.e., $q_{max}$ (maximum adsorption capacity) and b (energy of adsorption) decreased as the frequency of regeneration was increased. Experiment was further performed to evaluate the performance of the treatment scheme of chemical precipitation by ferrous iron waste followed by biological aerated filter (BAF). The overall removal efficiency in the system increased up to 80% and 90% for total phosphate (TP) and soluble phosphate (SP), respectively, and the corresponding effluent concentrations were detected below 2 mg/L and 1 mg/L for TP and SP, respectively. However, short-circuit problem was still unsolved operational consideration in this system. The practical concept applied in this study will give potential benefits in achieving environmentally sound wastewater treatment as well as environmentally compatible waste disposal in terms of closed substance cycle waste management.

• Korean Journal of Materials Research
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• v.10 no.6
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• pp.385-391
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• 2000

A kinetic study on the preparation of iron powder by hydrogen reduction of ferrous chloride vapor has been carried out both experimentally and theoretically. For the preparation of iron powder, ferrous chloride was vaporized and transported to a reaction zone by Ar gas used as carrier. Ferrous chloride vapor and hydrogen were mixed and subject to a reduction reaction at high temperature to produce iron powder and HCI gas. Iron powder was collected with organic solvent at the end of reaction zone and HCI gas was also absorbed in a caustic soda solution to determine the conversion ratio of ferrous chloride. For the development of rate equations, a 1st-order reaction and equilibration of ferrous chloride vapor with Ar gas were assumed. According to the results, the rate constant, k could be expressed as $k=7,879exp(-53,840/RT)\textrm{dm}^3/mole.sec$ and the activation energy was found to be 53.84kJ/mole. From TEM observation, the particle size distribution of iron powder produced was found to be in the range of $0.1~1.0{\mu\textrm{m}}$ which was not significantly influenced by reaction temperature or gas flow rates.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.24-31
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• 2008

Sulfate reducing bacteria (SRB) is universally distributed in the sediment, especially in marine environment. SRB reduce sulfate as electron acceptor to hydrogen sulfide in anaerobic condition. Hydrogen sulfide is reducing agent enhancing the reduction of the organic and inorganic compounds. With SRB, therefore, the degradability of organic contaminants is expected to be enhanced. Ferrous iron reduced from the ferric iron which is mainly present in sediment also renders chlorinated organic compounds to be reduced state. The objectives of this study are: 1) to investigate the reduction of TCE by hydrogen sulfide generated by tht growth of SRB, 2) to estimate the reduction of TCE by ferrous iron generated due to oxidation of hydrogen sulfide, and 3) to illuminate the interaction between SRB and ferrous iron. Mixed bacteria was cultivated from the sludge of the sewage treatment plant. Increasing hydrogen sulfide and decreasing sulfate confirmed the existence of SRB in mixed culture. Although hydrogen sulfide lonely could reduce TCE, the concentration of hydrogen sulfide produced by SRB was not sufficient to reduce TCE directly. With hematite as ferric iron, hydrogen sulfide produced by SRB was consumed to reduce ferric ion to ferrous ion and ferrous iron produced by hydrogen sulfide oxidation decreased the concentration of TCE. Tests with seawater confirmed that the activity of SRB was dependent on the carbon source concentration.

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.489-494
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• 2006

Goethite, hematite, magnetite and synthesized iron oxide are used as catalysts for Fenton-type oxidation of phenol. The synthesized iron oxides were characterized by X-ray diffraction (XRD), BET, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR). The catalytic activity of these materials is classified according to the observed rate of phenol oxidation. The effectiveness of the catalysts followed the sequence: ferrous ion > synthesized iron oxide >> magnetite hematite > goethite. According to these results, the most effective iron oxide catalyst had the structure similar to natural hematite. The surface oxidation state of the catalyst was between magnetite and hematite (+2.5 ~ +3.0). Phenol degraded completely in 40 min at neutral pH (pH = 7). Soluble ferric and ferrous ions were not detected in the filtrate from Fenton reaction solution by AAS. The formation of hydroxyl radicals was confirmed by EPR.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.11
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• pp.1146-1153
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• 2008

Numerical simulation was carried out to study the trichloroethylene (TCE) degradation by permeable reactive barrier (PRB), and revealed the effect of concentration of TCE, iron medium mass, and concentration of iron-reducing bacteria (IRB). Newly developed model was based on axial dispersion reactor model with chemical and biological reaction terms and was implemented using MATLAB ver R2006A for the numerical solutions of dispersion, convection, and reactions over column length and elapsed time. The reaction terms include reactions of TCE degradation by zero-valent iron (ZVI, Fe$^0$) and ferrous iron (Fe$^{2+}$). TCE concentration in the column inlet was maintained as 10 mg/L. Equation for Fe$^0$ degradation includes only TCE reaction term, while one for Fe$^{2+}$ has chemical and biological reaction terms with TCE and IRB, respectively. Two coupled equations eventually modeled the change of TCE concentration in a column. At Fe$^0$ column, TCE degradation rate was found to be more than 99% from 60 hours to 235 hours, and declined to less than 1% in 1,365 hours. At the Fe$^{2+}$ and IRB mixed column, TCE degradation rate was equilibrated at 85.3% after 210 hours and kept it constant. These results imply that the ferrous iron produced by IRB has lowered the TCE degradation efficiency than ZVI but it can have higher longevity.http://kci.go.kr/kciportal/ci/contents/ciConnReprerSearchPopup.kci#

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.133-134
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• 2005

• Nutritional Sciences
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• v.9 no.4
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• pp.295-300
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• 2006

Iron bound to heme appears to be more bioavailable than iron salts. A clinical study was performed to investigate the absorption efficiency of heme-iron and iron-salt products available. Heme-iron and nonheme-iron supplements have become available in Korea. We performed iron absorption studies to compare the absorption of heme-iron polypeptide (HIP) products made from digested hemoglobin, produced in Korea (HIPk) and imported from Japan (HIj), with that of iron salts. In the study, 80 subjects were divided into 5 groups (n=56): placebo group; 12 mg glucose, HIPk group; 12 mg iron as HIPk, HIj group; 12 mg iron as HIj, iron-salt group 1; 12 mg of iron as ferrous aminoacetate, and iron-salt group 2; 100 mg iron as ferrous aminoacetate. Changes in serum iron levels were measured at 3 and 5 hours post ingestion. Absorption of iron in HIPk was higher compared to HIj, iron-salt or placebo. There was a significant inverse correlation between low serum iron levels $(<80{\mu}g/dl)$ and iron absorption from HIPk. These results demonstrated that HIPk was more bioavailable, even taken with a meal, and would have potential advantages over iron salt or HIj as an iron supplement. Our results indicate that heme-iron absorption is regulated by iron status through a heme receptor, whereas iron-salt absorption is unregulated.