• Proceedings of the Korean Institute of Resources Recycling Conference
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• 1993.03a
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• pp.14.1-14
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• 1993

• The Korean Journal of Community Living Science
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• v.19 no.1
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• pp.75-85
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• 2008

This study investigated the effects of chitosan on mineral metabolism in rats exposed to cadmium by oral administration. Six week-old Sprague-Dawley rats were divided into eight groups. Four groups were fed AIN-93G based 3% ${\alpha}$-cellulose diets and the other four groups were fed 3% chitosan diets for four weeks with the oral administration of 0, 0.5, 1.0, 2.0 mg Cd/2ml distilled water three times per week, respectively. The essential mineral contents of serum, liver, kidney and bone (femur and lumbar), and the excretion of calcium in feces and urine were determined. There was no significant difference in weight gain and food intake among groups. The cadmium administration significantly decreased calcium in serum, iron in blood, calcium and iron in liver and iron contents in kidney. In contrast, calcium and zinc contents in kidney increased by the administration of cadmium. The weight, length and breaking forces of the femur and lumbar were not significantly different due to cadmium administration and chitosan among the groups. The fecal excretion of calcium was increased by the administration of cadmium. On the other hand, calcium absorption and the absorption rate were decreased by Cd administration. In the groups without Cd administered (N, N-Chi groups), chitosan significantly decreased the absorption rate of calcium by increasing the excretion in feces (p<0.05). These results suggest that cadmium administration may facilitate the decline of essential minerals in rats and also, chitosan may have a conflicting effect between cadmium and the essential minerals of tissues.

• Economic and Environmental Geology
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• v.4 no.2
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• pp.77-90
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• 1971

About four hundred deposits of iron, talc, fluorite, tungsten, molybdenum, lead, zinc and other polymetallic mineral deposits were plotted on the Ore Distribution Map of the Ockcheon Geosynclinal Area. These mineral deposits plotted on the map can be divided into the several metallogenic zones by the consideration of their geologic background including the sedimentary and tectonic cycles and the igneous activities in the geosynclinal evolution, as follows: a. Chungju iron and talc zones. b. Cheong-san copper bearing iron sulphide zone c. Kumsan-Muju fluorite-polymetallic zones. d. Cheong-an Puyong and Ein Suckseong gold zone e. Hwang-gan Seolcheon and Sangju gold zones. Chungju iron zone originated in the iron bed in the Kemyongsan Series corresponding to the Pre-Ockcheon Cycle of evolution history. In early period of the Ockcheon Cycle, Hyangsanri quartzite and Munjuri phyllitic formation corresponding to the lower terrigenous sequence were not mineralized while the next sequence of the Samsungsan basic igneous-metamorphic formation and the Changri limestone formation were mineralized by the copper bearing iron sulphide and the fluorite-polymetallic deposits respectively. Two generations of the gold zones are recognized. The earlier generation distributes directionaly in the outside of the Ockcheon sedimentary belt was followed by the earlier grantitic invasion of Jurasic in age, while the later generation scatters at random which was related to the nondirectional Cretaceous granitic intrusion of the Post-Ockcheon Cycle. Conclusively speaking, it was disclosed that the endogenic mineralization in the Ockcheon geosyn clinal zone was not conspicuous in its inner sedimentary belt except its limestone area but in its outer peripheral granitic or gneissic zones, and the related igneous activities occured in the Post-Ockcheon Cycle of evolution history.

• Journal of Nutrition and Health
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• v.38 no.6
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• pp.475-486
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• 2005

This study was intended to investigate the nutritional status between lactating and non- lactating women, especially calcium and iron. The subjects were 84 lactating women and 20 non-lactating women visiting a public health center and hospital in Daegu. Each subject was interviewed to collect the information on dietary intake for 2 consecutive days. Biochemical assessment of iron status and bone mineral density (BMD) measurement were conducted. Dietary intake of carbohydrate, potassium, Vit $B_1,\;B_2$, Vit C were significantly higher in women during lactating period (p<0.05). However, relative intake as expressed by percentage of Korean Recommended Dietary Allowances (RDA) was not significantly different between the two groups. The dietary intake of iron and calcium were 58.8%, 60.4% of Korean RDA respectively in women during lactating period. The current food habit score of these women was significantly higher than that of non-lactating women (p<0.05). When we compared the quality of nutritional status, the Index of nutritional quality (INQ) was significantly higher for vitamin $B_2$, P in lactating women than in non-lactating women (p<0.1). Mean adequacy ratio (MAR) was not significantly different between two groups. Dietary variety score (DVS) was significantly higher in women during the lactating period (p<0.05). There was no significant difference in biomarkers (Hb, Hct, Serum ferritin, Transferrin) related to iron status between the two groups. No significant difference in bone mineral density (BMD) T-score was not observed. However, it appeared that BMD of lactating women was lower than that of non-lactating women.

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

• Resources Recycling
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• v.31 no.2
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• pp.12-19
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• 2022

The study was conducted to develop a vanadium recovery process using reduction pre-treatment in the Vanadium TitanoMagnetite (VTM) The sample for the research was provided by the Gwan-in Mine in Pocheon, Gyeonggi-do. The vanadium content of the sample is 0.54 V₂O₅% and vanadium is concentrated mainly in magnetite and ilmenite. Magnetic separation of the sample can increase vanadium content up to 1.10 V₂O₅%. To increase the vanadium content further, reduction pre-treatment was performed, which is a process of concentrating vanadium present in the iron by reducing iron in magnetite using carbon(C). Based on this reduction pre-treatment, the magnetic separation process was developed, which achieved a vanadium grade of 1.31V₂O₅% and 79.68% recovery. In addition, XRD analysis of the vanadium concentrate before and after reduction and the final vanadium concentrate was performed to confirm the behavior of vanadium by reduction pre-treatment.

• Progress in Superconductivity and Cryogenics
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• v.18 no.1
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• pp.28-32
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• 2016

There are a few thousand abandoned metal mines in South Korea. The abandoned mines cause several environmental problems including releasing acid mine drainage (AMD), which contain a very high acidity and heavy metal ions such as Fe, Cu, Cd, Pb, and As. Iron oxides can be formed from the AMD by increasing the solution pH and inducing precipitation. Current study focused on the formation of iron oxide in an AMD and used the oxide for adsorption of heavy metals. The heavy metal adsorbed iron oxide was separated with a superconducting magnet. The duration of iron oxide formation affected on the type of mineral and the degree of magnetization. The removal rate of heavy metal by the adsorption process with the formed iron oxide was highly dependent on the type of iron oxide and the solution pH. A high gradient magnetic separation (HGMS) system successfully separated the iron oxide and harmful heavy metals.

• Journal of Community Nutrition
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• v.4 no.3
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• pp.159-163
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• 2002

A survey was performed to 238 male young men who were living alone (104 persons) or living with roommates (134 persons). Their average age was 22.6 years old, height 171.8cm, and weight 65.6kg. Their daily calcium intake level was averaged 271.9 $\pm$ 169.1mg, which was 38.8% of Korean Recommended Dietary Allowances(RDA). Comparing calcium intake of each mealtime, breakfast, lunch, dinner, and snacks were composed of 18.6%, 30.0%, 34.0% and 17.4%, respectively. Their daily iron intake level was averaged 8.9 $\pm$ 10.8mg, which was 74.3% of Korean RDA. Comparing iron intake of each mealtime, breakfast, lunch, dinner, and snacks were composed of 15.4%, 33.6%, 36.3% and 14.7%, respectively. Deficiency of these minerals in young male adults were severe and the nutrient qualities were also poor and the deficiency was more profound in calcium than in iron. And we observed iron nutrition differed significantly according to their living status, such as iron intake and its %RDA were significantly worse in single living subjects than the other. However calcium did not show significant difference. It was found mineral intake, especially iron, could be improved in young men living with roommates than living alone and regular breakfast could improve calcium and iron intakes. (J Community Nutrition 4(3) : 159~5163, 2002)

• The Korean Journal of Quaternary Research
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• v.13 no.1
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• pp.99-106
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• 1999

The surfacial bottom sediments on the nearshore to infer continental shelf off the Taean Peninsular, west coast of Korea are dominantly medium-grained clastic sands. About 60% and 20% of these clastic sands are partly iron-stained quartz and completely iron-stained quartz, respectively. Characteristically glauconite grains are abundantly found in these clastic sands. The mineral compositions of clastic sandy sediments in the study area are very similar to those of East China continental shelf sediments. Accordingly, such iron-stained quartz grains, glauconite grains and associated textural characteristics seem to indicate that those sandy sediments are relict sediments related to past condition, i.e. Quaternary low stands of sea level.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.432-436
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• 2001

In this study, calcium sulfate(gypsum) powder was obtained using waste sulfuric acid and stainless refinery sludge by- produced from chemical reagent and the iron industry, by the neutralization of waste sulfuric acid. As variables for the experiment the mole ratio of the H$_2$SO$_4$ : Ca(OH)$_2$, the pH, the reaction temperature and time, the amount of catalyst were used. The crystal shape and microstructure of obtained powder were observed by XRD and SEM, and the thermal property was investigated by DTA. As the NaCl is added 0~20wt% as a catalyst to the H$_2$SO$_4$ : Ca(OH)$_2$, system it can be found that the crystal shape goes through the processes as follows : gypsum dihydratlongrightarrowgypsum hemihydrate＋gypsum dihydratelongrightarrowgypsum hemihydrate. And gypsum hemihydrate is $\beta$-type as the result of DTA. As waste sulfuric acid and stainless refinery sludge were used, the pH of reacted solution (which was 0.8) was rapidly raised up to 8~9 by the addition of stainless sludge and gypsum dihydrate was produced as a by-product. Therefore, it was found that stainless refinery sludge is sufficiently applicable for the neutralization of waste sulfuric acid.