• Journal of the Mineralogical Society of Korea
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• v.16 no.1
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• pp.107-123
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• 2003

The objective of this study was to investigate mineral precipitates, which derived from the zero valent iron (ZVI) corrosion during TCE dechlorination and to find the controlling factors in mineral precipitates. A series of column experiemnts were conducted to evaluate the location of ZVI and the effects of electrode arrangements in electro-enhanced permeable reactive barrier (E2PRB) systems. Based on mineralogical study, ZVI samples near the influent port had more lepidocrocite, ferrihydrite or Fe (oxy)hydroxide, and (phospho)siderite while backward samples had more akaganeite, magnetite/maghemite, and intermediate green rust (GR) I and GR II. A suite of mineral distribution was preferabley related to the dissolved oxygen and the increased pH. Controlling factors of mineral precipitates in an E2PRB system were found to be (1) pH, (2) dissolved oxygen, (3) the types of Fe intermediates, and (4) anionic species to form complex strongly.

• Journal of Nutrition and Health
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• v.39 no.6
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• pp.539-548
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• 2006

In recent years a concern of excessive intakes of vitamins and minerals from various sources is increasing, since there has been a marked increase in production and consumption of vitamin and mineral supplements and fortified foods. The purpose of this study was to assess the maximum exposure of vitamins and minerals from various sources including diet, fortified foods, and health functional foods among Koreans. As a result, the highest exposure group of most vitamins and minerals from diet was adults (30 - 49 years of age) according to 2001 Korean National Nutrition and Health Survey Report. Maximum dietary intakes of vitamin A, $B_1,\;B_2$, C, nicotinamide, calcium, phosphorus and iron were 0.5 - 7 times of the RDA for Koreans, 7th ed. Maximum intakes of vitamins and minerals from fortified foods by adults (20 - 59 years of age) were 8 - 760% of the Korean RDA. In addition, maximum exposure of vitamins and minerals from vitamin mineral health functional foods by middle aged people was 35 - 140% of the upper limits (UL: DRI for Koreans). As a consequence, maximum combined intakes of vitamin $B_6$, vitamin C, calcium, iron and zinc from the above sources including diet, fortified foods and vitamin mineral health functional foods were greater than the UL. These results would be applied for determining the safe upper limits of vitamin and mineral of health functional foods.

• Korean Journal of Community Nutrition
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• v.9 no.3
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• pp.303-314
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• 2004

We studied daily micronutrient intake from vitamin-mineral supplements, health-related life style, clinical case of diseases and food frequency of the Korean middle-aged (40-59 yr, n = 404) to compare the characteristics of non-user (n = 270) and user (n = 134) of vitamin-mineral supplements. Rate of supplement use of the middle-aged was 33.2% and there was significant difference in education level (p = 0.0084) and family income (p = 0.0476) of user and nonuser. Smoking habit (p = 0.0844) and drinking frequency (p = 0.0606) tended to be lower in a supplement user than a non-user. The medical history of a case was significantly higher in users (67.9%) than in non-users (44.4%) (p = 0.001), which suggests that medical history is one of the important motivations of supplement use. Supplement users had the medical history of digestive disease (34.1%), anemia (11.0%) and hypertension (9.9%) in order. Vitamin C was the most frequently supplemented nutrient (81.3%) among vitamin-mineral supplement, and the next orders were vitamins E (73.1%), B$_2$(68.7%) and B$_{6}$ (60.4%). Mean intakes of vitamin B$_1$, iron, selenium, vitamin E, and vitamin C from supplement was 4,260%, 4,030%, 1,660% and 1,330% of RDA, respectively. The supplement users tended to consume most food items including milk ＆ milk products (p ＜ 0.01), rice (p ＜ 0.01), grains (p ＜ 0.05) and cookies (p ＜ 0.01) less frequently than non-users. Conclusively, nutrient intake of vitamin B$_1$, iron, selenium, vitamin E, and vitamin C from supplement was excessively high compared to RDA. We suggest that the toxic effect of excessive supplementation should he informed to supplement user and nutritional education should be focused on the optimal supplement dose.e.

• Resources Recycling
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• v.20 no.3
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• pp.68-76
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• 2011

For the separation of aluminum and iron from platinum mixtures, extraction resins were synthesized and separation efficiencies were compared with those by commercial one, $P_{204}$. During synthesis, the suspension polymerization method was adopted with D2EHPA as an extractant. Also, benzoyl peroxide as a starter was divided into 3parts and injected for the uniform size and dispersion of resin particles. Comparison tests resulted in 100% separation of Fe and Pt for both synthetic and $P_{204}$ resins. In case of Al and Pt, synthetic and $P_{204}$ resin gave extraction efficiencies of 99.9% and 98.9%, respectively. Difference in extractant contents of synthetic resin(61.8%) and $P_{204}$(60%) was considered to give differences in separation efficiencies of aluminum and iron elements. For both resins, separation efficiencies of Al and Fe increased up to $55^{\circ}C$. According to FT-IR analyses of both resins, specific peaks of D2EHPA and crosslinked polystyrene were identified at the wavenumber of $1000cm^{-1}$ and $2900cm^{-1}$ respectively.

• Journal of Nutrition and Health
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• v.38 no.7
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• pp.544-552
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• 2005

This study was conducted to examine the correlation among bone mineral density (BMD), hair and nail calcium and magnesium contents, and nutrient intakes in preschool children in Chungnam district. A total of 111 preschool children (61 boys, 50 girls) measured the anthropometric characteristics, the bone mineral density of carpus using DEXA and hair and nail calcium and magnesium contents were analyzed by ICP spectrometer. The average ages of the study subjects were 55.7 months in boys and 53.0 months in girls (3.8${\~}$7 years). The birth height and weight of subjects were 51.0 cm and 3.3 kg in boys and 50.3cm and 3.2kg in girls, respectively. The average height, weight, $\%$ body fat, and obesity index were 111.6 cm, 19.6 kg, $15.0\%,\;96.1\%$ in boys and 108.6 cm, 18.5 kg, $17.5\%,\;98.1\%$ in girls, respectively. The bone mineral density in carpus was $0.25 g/cm^2$ in boys and $0.24 g/cm^2$ in girls. The hair calcium and magnesium contents were 440.9 ppm, 16.4 ppm in boys and 373.2 ppm, 28.9 ppm in girls. The nail calcium and magnesium contents were 9.4 ppm, 2.1 ppm in boys and 10.4 ppm, 2.4 ppm in girls. The intakes of energy, calcium, iron, zinc, vitamin A. niacin, and vitamin C did not meet the Korean RDAs. The ultradis and average carpus BMD were positively correlated to the plant calcium intake (p < 0.05, p < 0.05). And the ultradis, distal, and average carpus BMD were positively correlated to the plant iron intake (p < 0.05, p < 0.05, p < 0.05). The average bone mineral density in the carpus was positively correlated to the nail magnesium content (p < 0.05). Therefore, more systematic studies to investigate the roles of iron and calcium intakes, nail magnesium content in bone development of preschool children were required.

• Korean Journal of Community Nutrition
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• v.1 no.3
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• pp.395-404
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• 1996

The effect of meal service for home-staying, urban elderly with low income on their mineral status and prevalence of clinical symptoms was evaluated. One hundred. One hundred and eighty three subjects were assigned to meal-served(served) and non-served(non-served)groups. A meal containing approximately one half of the RDA for energy, protein, calcium and iron was served as lunch every day to served group at a welfare center. Dietary, biochemical and clinical data were collected before and after 6 months of meal service and the changes of parameters were analyzed with paired t-test. served female showed significantly increased intake of calcium. The mean hemoglobin, serum iron, TIBC and serum copper of female were significantly increase with meal service. The proportion of anemic female compared to reference data on hemoglobin, hematocrit and serum iron were 45.5$\%$, 29.1$\%$ and 16.4$\%$ respectively, but were lowered to 18.2$\%$, 7.3$\%$, and 5.5$\%$ after 6 months of meal service. served male showed significant increase in MCHC, serum copper, and urinary Na. The urinary Ca/Creatinine, which is often used as an index of bone resorption, was decreased significantly in served group. The decrease in the proportion of served women suffering from edema of ankle and diarrhea was most apparent and less women reported feeling clinical symptoms of dizziness, constipation, difficulty in hearing, and coughing after meal service. The symptoms of benumbness of hands and feet and coughing was lowered most among men after meal service. Clinical symptoms of non-served elderly did not show improvement in feeling clinical symptoms except slightly decreased frequency in coughing of female and buzzing sound in the ears and diarrhea of male.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.2
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• pp.29-41
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• 1986

Effects of some mineral nutrients on the chlorine absorption by the plants, on the chemical constituents and physical properties of leaves were investigated tinder the paddy field and pot conditions. The chlorine content of cured leaf grown in paddy field was high in iron and manganese application groups and highest in combined application of iron and manganese. Lime application inhibited the absorption of chlorine and increased the yield and quality of cured leaf, and inhibited the absorption of iron and manganese those causing the grey leaf. Lime application reduced the leaf chlorine content and rate of muddy grey leaf by increasing the soil pH in acid soil.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.6
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• pp.495-506
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• 2000

The purpose of this study was to assess the nutritional status of iron and magnesium and the effect of von supplementation during 8 weeks(from 20 to 28 weeks of gestation) on serum iron and magnesium status of 31 pregnant women in Kyunsin area. The age, weight, and height of the subjects before pregnancy were investigated by questionnaires. At 20 and 28 weeks of gestation, data for food and nutrient intake were obtained by questionnaires and serum sample was obtained. According to the frequency of iron supplementation, subjects were divided into two groups(4$\geq$/wk) The mean iron supplementation of 5 $\geq$/wk group(63.mg/day) was significantly higher than 4$_2$ intakes were much less than the Korean RDA. Especially, calcium, iron and magnesium intakes showed half the levels compared with Korean RDA. At 28 weeks of gestation the serum total protein(p<0.001), albumin(p<0.01) and globulin(p<0.001) were significantly decreased. Total iron binding capacity(TIBC) was significantly increased(P<0.001), but serum ferritin(p<0.01) and magnesium(p<0.01) concentrations were significantly decreased. However, even 28 weeks of gestation 5$\geq$/wk group showed higher serum iron and ferritin concentration and lower TIBC than 4$\geq$/wk group. Therefore, iron supplementation should be conducted with concerning the mineral balance like magnesium.

• Resources Recycling
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• v.32 no.6
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• pp.54-66
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• 2023

Titanium's importance as a mineral resource is increasing, but the Korean industry depends on imports. Ilmenite is the principal titanium ore. However, research and development from raw materials have not been investigated yet in detail. Hence, measures to secure a stable titanium supply chain are urgently needed. Accordingly, through beneficiation technology, we evaluated the possibility of technological application for the efficient recovery of valuable minerals. As a result of the experiments, we confirmed that mineral particles existed as fine particles due to weathering, making recovery through classification difficult. Consequently, applying beneficiation technologies, i.e., specific gravity separation, magnetic separation, and flotation, makes it possible to recover valuable minerals such as hematite and rutile. However, there are limitations in increasing the quality and yield of TiO₂ due to the mineralogical characteristic of the hematite and rutile contained in titanium ore. Hametite is combined with rutile even at fine particles. Therefore, it is essential to develop mineral processing routes, to recover iron, vanadium, and rare earth elements as resources. On that account, we used grinding technology that improves group separation between constituent minerals and magnetic separation technology that utilizes the difference in magnetic sensitivity between fine mineral particles. The development of beneficiation technology that can secure the economic feasibility of valuable materials after reforming iron oxide and titanium oxide components is necessary.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.76-82
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• 2006

Fenton's reaction are difficult to apply in the field due to the low pH requirements for the reaction and the loss of reactivity caused by the precipitation of iron (II) at neutral pH. Moreover, Fenton-like reactions using iron mineral instead of injection of iron ion as a catalyst are operated to get high removal result at low pH. Because hydroxyl radical can generate at the surface of iron mineral, there are competition with a lot of hydroxide at around neutral pH. On the other side, to operate Fenton's reaction series at neutral pH, modified Fenton reaction is suggested. The complexes, composed by iron ions (ferrous ion or ferric ion)-chelating agent, could be acted as a catalyst and presented in the solution at neutral pH. However, modified Fenton reaction requires a lot of hydrogen peroxide. Accordingly, the purpose of this experiment was to effectively combine Fenton-like reaction and modified Fenton reaction for extending application of Fenton's reaction. i.e., injecting chelating agents in Fenton-like reaction at around neutral pH is increasing the concentration of dissolved iron ion and highly promoting the oxidation effect. 2,4,6-trinitrotoluene (TNT) was used as a probe compound for comparing reaction efficiencies in this study. If the concentration of dissolved iron ion in combined Fenton process were existed more than 0.1 mM, the total TNT removal were increased. Magnetite-NTA system showed the best TNT removal (76%) and Magnetite-EDTA system indicated about 56% of TNT removal. The results of these experiments proved more promoted 40-60% of TNT removal than Fenton-like reaction's.