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

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

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.5
• /
• pp.864-868
• /
• 2004

Iron is an essential ingredient for all metabolism in a living body However, because of the very low content of the iron in foods, many researches have been performed about iron-fortified food additives. We developed an iron-fortified food additive using the liposome that contain ferrous sulfate and hemin. For preventing the autoxidation of the ferrous sulfate, ascorbic acid was applied. Also, to prevent the oxidation of the liposome induced by the added ferrous sulfate and/or hemin, $\alpha$ -tocopherol was additionally applied. Though the effect of the added aqueous ascorbic acid did not show the antioxidative activity on the liposome containing ferrous sulfate and/or hemin, the added $\alpha$ -tocopherol in the phospholipid bilayer could retard the oxidation of the liposome. These results support that the liposome containing ferrous sulfate, hemin and ascorbic acid with the incorporated $\alpha$ -tocopherol could be applied in the food industry as an iron-fortified additive.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.1
• /
• pp.73-81
• /
• 2000

The removal of ferrous iron (Fe(II)) in groundwater is generally achieved by simple aeration or the addition of oxidizing agent. Aeration followed by solid-liquid separation is the most commonly used as physico-chemical treatment method for iron removal. In general aeration has been shown to be very efficient in insolubilizing ferrous iron at the pH level greater than 6.5. In this study pH was maintained over 6.5 using limestone granules under constant aeration to oxidize ferrous iron. In batch experiments, oxidation rate of ferrous iron was investigated under different conditions including limestone granule size. initial concentration of the ferrous iron, pH, temperature and ionic strength in groundwater. The pH in groundwater was presumed as the most important factor determining oxidation rate of ferrous iron. According as the size of the limestone granules decreased, the pH of the iron contaminated water increased quickly and oxidation of the ferrous iron was achieved immediately too. The oxidation rate of the ferrous iron was found to be proportion to initial concentration of the iron contaminated water, temperature and ionic strength, respectively.

• Journal of the Korean Ceramic Society
• /
• v.48 no.2
• /
• pp.117-120
• /
• 2011

In this study, the redox state of iron in sodium silicate glasses was varied by changing the melting conditions, such as the melting temperature and particle size of iron oxide. The oxidation states of the iron ion were determined by wet chemical analysis and UV-Vis spectroscopy methods. Iron commonly exists as an equilibrium mixture of ferrous ions, $Fe^{2+}$, and ferric ions $Fe^{3+}$. In this study, sodium silicate glasses containing nanoparticles of iron oxide (0.5% mol) were prepared at various temperatures. Increase of temperature led to the transformation of ferric ions to ferrous ions, and the intensity of the ferrous peak in 1050 nm increased. Nanoparticle iron oxide caused fewer ferrous ions to be formed and the $\frac{Fe^{2+}}{Fe^{3+}}$ equilibrium ratio compared to that with micro-oxide iron powder was lower.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.3
• /
• pp.542-546
• /
• 1999

Uncoated, ethyl cellulose(EC) coated or methacrylic acid copolymer(MAC) coated ferrous sulfate was added to the yoghurt made from whole milk powder and quality changes of those yoghurt were observed. Among treatments uncoated ferrous sulfate added yoghurt showed the lowest quality in the view of pH, total acidity, total counts of lactic acid bacteria, and sensory characteristics. Quality change of MAC comparing to control was lower than that of EC. MAC and EC showed higher TBA value than no iron added or uncoated iron added one during storage. From sensory evaluation, MAC was not signif icantly different from control in color and off flavor after one day storage(p>0.05), however significant difference was observed in off flavor after 7 day storage(p<0.05). From above results, MAC coated ferrous sulfate added yoghurt showed better quality than uncoated or EC coated ferrous sulfate added one during storage.

• Resources Recycling
• /
• v.16 no.3 s.77
• /
• pp.19-26
• /
• 2007

The bottom ash of municipal solid waste incineration generated during incineration of municipal solid waste in metropolitan area consists of ceramics, glasses, ferrous materials, combustible materials and food waste and so on. Although the ferrous material was separated by the magnetic separation before the incineration process, of which content accounts for about $3{\sim}11%$ in bottom ash. The formation of a $Fe_3O_4-Fe_2O_3$ double layer(similar to pure Fe) on the iron surface was found during air-annealing in the incinerator at $1000^{\circ}C$. A strong thermal shock, such as that takes place during water-cooling of bottom ash, leads to the breakdown of this oxidation layer, facilitating the degradation of ferrous metals and the formation of corrosion products and it existed as $Fe_2O_3,\;Fe_3O_4\;and\;FeS_2$. So, many problems could occur in the use of bottom ash as an aggregate substitutes in construction field. Therefore, in this study, the separation of ferrous materials from municipal solid waste incineration bottom ash was investigated. In the result, the ferrous product(such as $Fe_2O_3,\;Fe_3O_4,\;FeS_2$ and iron) by magnetic separator at 3800 gauss per total bottom ash(w/w.%) accounted for about 18.7%, and 87.7% of the ferrous product was in the size over 1.18 mm. Also the iron per total bottom ash accounted for about 3.8% and the majority of it was in the size over 1.18 mm.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.9
• /
• pp.1013-1018
• /
• 2014

Magnetic Abrasive Polishing (MAP) process is a nontraditional method for polishing the surface of workpiece by using the flexibility of tool. At present, a mixture of polishing abrasives and ferrous particles is used as the tool in the MAP process. Previously, an experiment was conducted with different sizes of polishing abrasives with an aim to improve the polishing accuracy. However, the sizes of ferrous particles are also expected to have a dominant effect on the process, warranting a study on the effect of the size of ferrous iron particles. In this study, an experiment was conducted using three different sizes of ferrous particles. Iron powder of average diameters 8, 78 and $250{\mu}m$ was used as ferrous particles. The effect of each ferrous particle size was evaluated by comparing the improvements in surface roughness. The particle size of a ferrous iron was found to play a significant role in MAP and particles of $78{\mu}m$ facilitated the best improvement in surface roughness.

• Journal of the Korean institute of surface engineering
• /
• v.15 no.4
• /
• pp.218-225
• /
• 1982

The effects of ferrous ion on the properties of bright nickel electrodeposit were exa-mined. Iron exists as ferrous ion (Fe+2) and ferric ion (Fe+3) in the bath, a portion of the former tend to be oxidized to the somewhat harmful ferric ion. Iron was added to bath as the ferrous sulfate, ferrous ion prevented from the oxidation with citric acid. It was found that the hardness was increased as the concentration of ferrous ion, the ductility was slightly increased too. The appearance can obtain the wide bright deposits within 4g/$\ell$. The corrosion resistance drastically dropped from 5g/$\ell$ In the case of considering the effect of ferrous ion on the corrosion resistance and the appearance, the allowable limits is 4g/$\ell$, if the reductant is used.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.11
• /
• pp.2577-2583
• /
• 2009

Presented are the formation of iron oxide layers on evaporator tubes in an actual fossil power plant operated under all volatile treatment (AVT) condition and an experimental simulation of iron oxide formation in the presence of ferrous and ferric ions. After actual operations for 12781 and 36326 hr in the power plant, two iron oxide layers of magnetite on the evaporator tubes were found: a continuous inner layer and a porous outer layer. The experimental simulation (i.e., artificial corrosion in the presence of ferrous and ferric ions at 100 ppm level for 100 hr) reveals that ferrous ions turn the continuous inner oxide layer on tube metal to cracks and pores, while ferric ions facilitate the production of porous outer oxide layer consisting of large crystallites. Based on a comparison of the oxide layers produced in the experimental simulation with those observed on the actually used tubes, we propose possible routes for oxid layer formation schematically. In addition, the limits of the proposed corrosion routes are discussed in detail.