• Resources Recycling
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• v.23 no.3
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• pp.30-36
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• 2014

A large amount of waste copper slag containing about 35 ~ 45% iron has been generated and discarded every year from pyrometallurgical processes for producing copper from copper concentrate. Thus, recovery of iron from the waste copper slag is of great interest for comprehensive use of mineral resource and reduction of environment problems. In this study, a physico-chemical separation process for upgrading iron from the waste copper slag discharged as an industrial waste has been developed. The process first crushes the waste copper slag below 1 mm (first crushing step), followed by carbon reduction at $1225^{\circ}C$ for 90 min (carbon reduction step). And then, resulting material is again crushed to $-104{\mu}m$ (second crushing step), followed by wet magnetic separation (wet magnetic separation step). Using the developed process, a magnetic product containing more than 66 wt.% iron was obtained from the magnetic separation under a magnetic field strength of 0.2 T for the waste copper slag treated by the reduction reaction. At the same conditions, the percentage recovery of iron was over 72%. The iron rich magnetic product obtained should be used as a iron resource for making pig iron.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.280-286
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• 2014

Four thermophilic bacterial species, including the iron-reducing bacterium Geobacillus sp. G2 and the sulfate-reducing bacterium Desulfotomaculum sp. SRB-M, were employed to integrate a bacterial consortium. A second consortium was integrated with the same bacteria, except for Geobacillus sp. G2. Carbon steel coupons were subjected to batch cultures of both consortia. The corrosion induced by the complete consortium was 10 times higher than that induced by the second consortium, and the ferrous ion concentration was consistently higher in iron-reducing consortia. Scanning electronic microscopy analysis of the carbon steel surface showed mineral films colonized by bacteria. The complete consortium caused profuse fracturing of the mineral film, whereas the non-iron-reducing consortium did not generate fractures. These data show that the iron-reducing activity of Geobacillus sp. G2 promotes fracturing of mineral films, thereby increasing steel corrosion.

• Journal of the Mineralogical Society of Korea
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• v.31 no.3
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• pp.215-225
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• 2018

Musan iron deposit in North Korea and iron deposits in Anshan-Benxi area in China are Archean banded iron formations and included in Longgang block in Eastern block of North China Craton. Host formations of Musan iron deposit and Anshan-Benxi iron mineralized belt are Musan group and Anshan group, respectively. These groups consist of magnetite-bearing quartzite, amphibolite, schist, and migmatite. Host rock of banded iron formation in Musan deposit and Anshan-Benzi mineralized belt is magnetite-bearing quartzite. Shape of ore bodies in Musan deposit is horse's hoof due to the fold while shape of orebodies in Anshan-Benxi mineralized belt is layer. The previous studies revealed the both of banded iron formations are contemporaneously deposited during the late Archean (Musan deposit and iron deposits in Anshan-Benxi area: 2.66-2.52 Ga and 2.55-2.53 Ga, respectively). Musan deposit and iron deposits in Anshan-Benxi mineralized belt belolng to Algoma type BIFs. In conclusion, the characteristics of geology, formation ages, and deposit types of Musan deposit and Anshan-Benxi minerlized belt are very similar.

• Korean Chemical Engineering Research
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• v.53 no.1
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• pp.39-45
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• 2015

We produced magnetite nanoparticles (MNPs) and a Mg-rich solution as a nano-adsorbent and a coagulant for water treatment, respectively, using a low-grade iron ore. The ore was leached with aqueous hydrochloric acid and its impurities were removed by solvent extraction of the leachate using tri-n-butyl phosphate as an extractant. The content of Si and Mg, which inhibit the formation of MNPs, was reduced from 10.3 wt% and 15.5 wt% to 28.1 mg/L and < 1.4 mg/L, respectively. Consequently, the Fe content increased from 68.6 wt% to 99.8 wt%. The high-purity $Fe^{3+}$ solution recovered was used to prepare 5-15-nm MNPs by coprecipitation. The wastewater produced contained a large amount of $Mg^{2+}$ and can be used to precipitate struvite in sewage treatment. This process helps reduce the cost of both sewage and iron-orewastewater treatments, as well as in the economic production of the nano-adsorbent.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.19 no.2
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• pp.123-129
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• 2016

Purpose: This study was performed to evaluate the dietary nutrient intake status and hair mineral content of Korean young children. Methods: Fifty-five children who visited Seoul National University Bundang Hospital were divided into three groups by age: infants, toddlers, and preschoolers. The 24-hour recall method was used to collect the food intake data of the subjects. Hair mineral analysis was conducted using a Mass Spectrometer. Serum iron, ferritin, and calcium were also measured. Results: The mean energy intakes of the subjects were 730.3 kcal, 994.3 kcal, and 1,482.9 kcal for each age group. The mean percentage of energy intake compared to recommendation was 101.4% and was not different by age group. Toddlers of 37.8% and preschoolers of 54.5% consumed less than the Estimated Average Requirement (EAR) of calcium. Infants of 28.6%, toddlers of 10.8% and preschoolers of 9.1% consumed less than the EAR of iron. In the case of zinc, copper, and selenium, only 0% to 5% of toddlers and none of the preschoolers consumed less than the EAR of those minerals. The hair calcium, iron and copper concentrations were lower in toddlers and preschoolers than those in infants. Serum calcium levels of preschoolers were significantly lower than those of infants, whereas serum iron and ferritin levels were not. Conclusion: Hair calcium, iron, and copper concentrations were significantly lower in toddlers and preschoolers than in infants. Insufficient dietary intake of calcium and iron seems to be related with decreased hair mineral contents in young children.

• Korean Journal of Materials Research
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• v.16 no.8
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• pp.497-502
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• 2006

Recently, many attention have been focused on illite as a material for the well-being industry. Illite contains various kinds of iron bearing materials and they restrict their usage. In this study, Fe impurities in the illite produced in Yeongdong-gun, Chungcheongbuk-do were characterized and their removal experiments were performed. According to the characterization of illite raw ore, it contained 1.54 wt.%$Fe_2O_3$ due to the existence of iron oxide($Fe_2O_3$) and pyrite($FeS_2$). The raw ore was crushed into 3 mm or less using cone crusher and then ground by rod mill for the liberation of impurity mineral. For the removal of iron bearing minerals, an acid treatment, a flotation, a magnetic separation, and a flotation combined with magnetic separator were performed respectively. When the illite raw ore was treated with magnetic separation and various kinds of acid, 1.54wt.%. $Fe_2O_3$ content was reduced to 0.78 and 1.0 wt.%, respectively. On the other hand $Fe_2O_3$ content was reduced to be 0.52 wt.% after flotation. These results indicate that iron bearing minerals cannot be reduced below 0.3wt.%$Fe_2O_3$. However, combination of magnetic separation and flotation enable us to get 0.24wt.% of illite concentrate. It is concluded that, for the refinement of illite from Yeongdong-gun, the flotation combined with magnetic separation is good for high purity illite.

• Journal of Magnetics
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• v.13 no.3
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• pp.106-109
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• 2008

Almost monodisperse iron oxide nanoparticles with an average particle size ranging from 5 to 43 nm were fabricated using an environmentally friendly starting material, ferrous acetate. The smallest particles were formed in the presence of a reductant, 1,2-dodecanediol, while the particle size increased with increasing concentration of dispersing agents. The dispersants consisted of various combinations of oleic acid, oleylamine, trioctylphosphine, and polyvinylpyrrolidone. The threshold temperature to form crystalline particles was found to be $240^{\circ}C$. The 43 nm nanoparticles exhibited a room temperature saturation magnetization and coercivity of 57 emu/g and 47 Oe, respectively.

• Nutritional Sciences
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• v.8 no.1
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• pp.71-76
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• 2005

The purpose of this study was to investigate the relationship between nutritional status of iron and bone minernl density in premenopausal women. In the study, we classified the subjects into osteopenia (-2.5-I, n=29) groups according to their lumbar spine bone mineral density. Anthropometric measurements, dietary intake analysis and blood biochemistry measurements were performed on the subjects. The average ages of those in the osteopenia and normal groups were 22.2 yrs and 23.0 yrs, respectively, with no significant difference. The average body mass index (p<0.05) of those in the osteopenia group (19.6) was significantly lower than that of the normal group (21.3). The mean protein intake of those in the osteopenia group was significantly lower than that (p<0.05) the subjects in the normal group. The osteopenia group consumed a significantly lower amount of iron (p<0.05) and non-heme iron (p<0.05) compared to the normal group. The intakes of total food, vegetables and milk of those in the osteopenia group were significantly lower than those of the subjects in the normal group. The serum ferritin (p<0.001) level of those in the osteopenia group was significantly lower than those of the subjects in the normal group. In conclusion, a balance of iron status may be helpful in the prevention of bone mass loss in premenopausal young women.

• The Journal of the Petrological Society of Korea
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• v.18 no.4
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• pp.307-314
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• 2009

Zapla iron ore bodies in Jujuy state, northern Argentina are located within Paleozoic Silurian marine sedimentary rocks and can be categorized into ironstone deposit. Iron ores contain oolitic hematite as main iron mineral as well as siderite and chamosite. Hematite replaced biotite and/or muscovite along their cleavage or grain boundary, which indicates hematite is precipitated by chemical reaction. Silurian basins in northern Argentina has high potential resources for ironstone deposit but economic aspects of ore body can be controlled by magnitude of lateral vertical extensions and local grade variation of iron beds.

• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.230-238
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• 1995

Iron and zinc were bound by neutral detergent fiber (NDF) obtained from 15 kinds of vegetables being consumed commonly in Korea. Binding capacity of Fe and Zn of NDF ranged from 37.8% to 85.5% and from 81% to 25.5%, respectively showing higher binding capacity of Fe to NDF than of Zn. Both Fe and Zn binding capacity of NDF increased as pH increased and reached to a maximum at pH 7 In all vegetables. The amount of mineral (Fe and Zn) bound to NDF increased as mineral concentration Increased.