• The Journal of the Petrological Society of Korea
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• v.22 no.4
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• pp.299-305
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• 2013

It is well known that the Hongcheon iron-rare earth deposit is composed of carbonatite-phoscorite complex. We conducted zircon U-Pb age determination for the gneissic country rocks of this deposit. As the result we obtained ca. 1830 Ma, which is somewhat younger than igneous and metamorphic ages of ca. 1870 Ma generally reported from the Gyeonggi massif, suggesting further investigations for the timing and evolution of the Paleoproterozoic activities of the Gyeonggi massif.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.4
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• pp.285-290
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• 1990

The mineral contents of Japonica(34 varieties) and J/Indica(25 varieties) brown rices sho-wed that phosphorus an magnesium contents were statistically different. However iron and magnesium contents were significantly different between Japonica and J/Indica milled rices. The coefficients of variance for minerals of brown and milled rices were lowever in J/Indica than Faponica Barieties. The contents of calcium magnesium iron copper manganese and zinc of Japonica brown rices were positively correlated with those of milled rices. on the other hand J/Indica brown rices had a positive correlation with milled rices in calcium copper manganese and zinc and a negative correlation in iron. Milled rices of both Japonica and J/Indica varieties showed similar results in terms of correlation among minerals.

• Journal of Soil and Groundwater Environment
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• v.21 no.1
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• pp.40-48
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• 2016

A siderophore-producing bacterium (i.e., Pseudomonas aeruginosa) capable of chelating Fe³⁺ from its mineral form (i.e., iron oxides) was used to enhance As uptake by plants. Since As in soil is mainly associated with iron oxides, siderophore can play an important role in As mobilization through the dissolution of As-bearing iron oxides. A series of pot experiment using Pteris cretica showed that As removal by P. cretica with siderophore-producing bacteria addition increased more than three times compared to that without bacteria addition. Competition between indigenous bacteria and introduced bacteria (i.e., P. aeruginosa) was also observed, but such competition seemed not to be significant. This study suggests that enhanced-phytoremediation by siderophore-producing bacteria addition could be a visible option for longterm As removal in the forest area at the former Janghang smelter site.

• Korean Journal of Microbiology
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• v.11 no.4
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• pp.189-195
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• 1973

With the gradual expansion of copper demands, the utilization of enormous tonnages of waste copper mineral containig up to 0.5% copper becomes available. In order to investigate the possibilities on the application of bacterial leaching method to waste dumps or abandoned mines, the authors had carried out microbial leaching of copper minerals by F.ferrooxidans isolated from the Dalsung copper mine water. The results obtained were as follows : 1. The copper extraction rate from the Dalsung chalcopyrite has been a little accerelated by using flasks in place of percolators. 2. The percentage of copper extracted from the Dalsung chalcopyrite sample was 100% in 30 days in the presence of iron-oxidizing bacteria F.ferrooxidans while 9.27% in the absence of bacteria. 3. F.ferroxidans was capable of producing sufficient quantities of ferric sulfate and sulfuric acid from ferrous iron to bring about the dissolution of 100% of copper from the Dalsung chalcopyrite.

• Particle and aerosol research
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• v.13 no.1
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• pp.33-40
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• 2017

Cobalt-iron oxides have emerged as alternative electrode materials for supercapacitors because they have advantages of low cost, natural abundance, and environmental friendliness. Graphene loaded with cobalt ferrite ($CoFe_2O_4$) nanoparticles can exhibit enhanced specific capacitance. In this study, we present three-dimensional (3D) crumpled graphene (CGR) decorated with $CoFe_2O_4$ nanoparticles. The $CoFe_2O_4$-graphene composites were synthesized from a colloidal mixture of GO, iron (III) chloride hexahydrate ($FeCl_3{\cdot}6H_2O$) and cobalt chloride hexahydrate ($CoCl_2{\cdot}6H_2O$) respectively, via one step aerosol spray pyrolysis. Size of $CoFe_2O_4$ nanoparticles was ranged from 5 nm to 10 nm when loaded onto 500 nm CGR. The electrochemical performance of the $CoFe_2O_4$-graphene composites was examined. The $CoFe_2O_4$-graphene composite electrode showed the specific capacitance of $253F\;g^{-1}$.

• Biomedical Science Letters
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• v.16 no.4
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• pp.293-298
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• 2010

Several risk factors for osteoporosis are known relatively well. Some nutrients are directly or indirectly needed for metabolic processes related to bone. Recently, an increased prevalence of osteoporosis has been reported in patients with hemochromatosis, an iron overload disease. Thus, the aim of this study was to find out if there was any relationship between serum ferritin and T-score of bone mineral density in healthy women. We recruited 1,101 subjects females aged between 39 and 85 years. We measured serum ferritin, glucose tolerance indices, lipid profiles, inflammatory indices, hormones, calcium, alkaline phosphatase. Also, anthropometric, blood pressure, and bone mineral density measurements were performed. T-score was negatively correlated with age (r=-0.425; P<0.01), systolic (r=-0.109; P<0.01) and diastolic (r=-0.093; P<0.01) pressure, follicular stimulation hormone (r=-0.190; P<0.01), alkaline phosphatase (r=-0.235; P<0.01), and serum ferritin (r=-0.090; P<0.05) and positively with body mass index (r=0.050; P=0.01), HDL-cholesterol (r=0.314; P<0.01), and estradiol (r=0.200; P<0.01). After adjustment for age, alkaline phosphatase, body mass index, HDL-cholesterol, estradiol, and follicular stimulation hormone, serum ferritin was independently inversely correlated with T-score (${\beta}$=-0.001; P<0.05). It is possible that an increase of serum ferritin in females be risk to osteoporosis.

• Economic and Environmental Geology
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• v.27 no.2
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• pp.117-130
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• 1994

Titanomagnetite ore bodies in the Yonchon iron mine are closely associated with alkali gabbroic rocks of middle Proterozoic age which intruded Precambrian metasedimentary rocks. The orebodies can be divided into massive ores in gabbroic rock, skarn ores in calcareous xenoliths and banded ores in gneissic gabbro. Gabbroic rocks from the Yonchon iron mine have unusually high content of $TiO_2$ with an average values of 3.46 wt%. Iron ores are ilmenite (42.25~51.56 wt% in $TiO_2$) and titanomagnetite (1.29~6.57 wt% in $TiO_2$) and the former is dominant Small amount of magnetite, hematite, sphene and sulfide minerals are included in the ores. Grandite garnet, titanoaugite and tschermakite are in iron skarn ores. Hornblendes from ores and gabbroic rocks have a relatively homogeneous isotopic composition with ${\delta}D$ between -110.0 and -133.9‰, and ${\delta}^{18}O$ of +4.5 to +6.5‰, and calculated to have formed in fluids with ${\delta}O_{H_2O}$ of + 6.7 to +8.7‰. and ${\delta}_{H_2O}$ of -87.9 to -111.8‰, which has a similar isotopic value of primary magmatic water. Based on intrusive age, occurrence, mineral chemistry and isotopic compositions of magnetite ores and gabroic rocks, it will be concluded that the gabbroic rocks are responsible for the titanomagnetite mineralization. The titaniferous magnetite melt was immiscibly separated from the high titaniferous gabbroic melts of Proterozoic age.

• Journal of Nutrition and Health
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• v.26 no.6
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• pp.772-782
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• 1993

This study was conducted to assess the relationships between maternal dietary intakes and milk contents of minerals and trace elements, and the correlation among levels of these milk constituents. Maternal dietary intakes were measured and milk samples were collected at 2∼5 days, 2, 4, 6 and 12 weeks postpartum from 29 lactating women. The results obtained are sumarized as follows: 1) The overall mean nutrient intakes of lactating women in this study were below the recommended allowances and there were extensive individual variations between subjects. 2) Concentrations of minerals and trace elements in matured human milk showed the same range reported from different countries with the exception of calcium, magnesium, manganese and molybdenum which were relatively high. 3) There were no significant relationships between maternal dietary intakes of minerals and the corresponding mineral levels of human milk. In addition, no significant correlations were found between maternal vitamin C intake and the iron contents of milk. These were significant positive correlations between maternal calcium intake and the magnesium level of milk ; between maternal protein intake and the contents of zinc and copper in human milk. Maternal energy intake was negatively correlated with milk sodium level. 4) Pearson correlation coefficient showed positive significant relationships between levels of 17 pairs of various mineral and trace elements : sodium and potassium, iron ; potassium and calcium, phosphors, magnesium, iron, copper, manganese ; calcium and magnesium, iron manganese, molybdenm, nickel ; magnesium and iron, molybdenum ; iron and copper ; nickel and manganese.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.231-231
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• 2003

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.441-442
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• 2005