• Journal of the Mineralogical Society of Korea
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• v.23 no.3
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• pp.191-197
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• 2010

Fine nickel metal powder of uniform morphology, narrow size distribution, and high purity was prepared from high purity metal solution. Slurry reduction method for the synthesis of metal powder was applied with a special interest in their fine and spherical shape. The products were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Well dispersed ultrafine nickel powder with the particle size range of 100~200 nm was produced from Ni-hydrazine precursor using hydrazine as a reductant for 90 min reaction in 4.5 M NaOH solution.

• Particle and aerosol research
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• v.9 no.2
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• pp.51-57
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• 2013

A graphene(GR)-$TiO_2$ composite was synthesized from colloidal mixture of graphene oxide(GO) nanosheets and $TiO_2$ nanoparticles by an aerosol assisted self-assembly. The morphology, specific surface area and pore size of asprepared GR-$TiO_2$ composite were characterized by FE-SEM, BET, and BJH respectively. The shape of GR-$TiO_2$ composite was spherical. The average particle size was 0.5-1 ${\mu}m$ in diameter and the pore diameter ranged 20-50 nm. Photovoltaic characteristics of a mixture of the GR-$TiO_2$ and $TiO_2$ nanoparticles were measured by a solar simulator under simulated solar light. The highest photoelectric conversion efficiency of the mixture photoanode was 5.1%, which was higher than that of $TiO_2$ photoanode.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.2
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• pp.103-111
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• 2011

This study examined rheological properties of blast furnace slag and ash paste that are widely used as cement concrete for mineral admixture in current. In that way rheological properties of the paste of mineral admixture only was examined. The result of this study were as follow: In order to analyze that the rheological properties of the mineral admixture only, fine particles were produced with grinding machine to 3 particle sizes. These powders in general from the result of comparison with and analysis of rheological properties and the coefficient n and De values. The result that ash powder was higher in plastic viscosity and yield stress than Slag powder, and with the same n value, ash powder showed higher plastic viscosity and yield stress than Slag powder. But Slag powder in particle size distribution showed a sensitive tendency on changing in rheological properties.

• Korean Journal of Human Ecology
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• v.8 no.1
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• pp.25-31
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• 2005

Chemical components of the physiological activity substance in Zizyphus jujuba seed were analyzed for the use as an functional processed products. The proximate compositions of Zizyphus jujuba seed were carbohydrate 89.40%, moisture 8.23%, crude protein 1.22%, crude fat 0.65% and crude ash 0.50%, respectively. the richest mineral contained in Zizyphus jujuba seed was Mg(198.3mg/100g), followed by Mn(113.0mg/100g), K(100.2mg/100g), Ca(25.3mg/100g), P(25.6mg/100g_, Fe(23.5mg/100g), Zn(18.7mg/100g), Cu(7.4mg/100g) and Na(5.3mg/100g). Total amino acid contents of Zizyphys jujuba seed were 1103.12mg/100g, and the major amino acids were proline(235.17mg%), aspartic acid(175.941mg%), gltamic acid(101.46mg%), leucine(50.27mg%), serine(47.71mg%), aspartic acid(47.27mg%), glycine(41.60mg%) and lysine (33.78mg%), respectively. The amount of free amino acids in the protein of Zizyphus jujuba seed were 178.62 mg/100g, and the major free amino acids were proline(121.30mg%), alanine(6.01mg%), valine(2.63mg%) and arginine(2.04mg%), respectively. The compositions of major total fatty acid in the lipid Zizyphus jujuba seed were C18:2(n5c) 28.72%, C18:1(n9t) 23.76%, C18:1(n9c) 13.45%, C16:0 13.45% and C20:5(n3) 1.77% in order, respectively.

• Korean Journal of Community Nutrition
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• v.18 no.3
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• pp.269-282
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• 2013

This study was carried out to investigate bone mineral density (BMD), blood pressure, calcium, sodium intake and related biochemical variables, and to analyze the relationship between BMD, and blood pressure, physical characteristics, nutrient intakes of Korean adult women. The study subjects were 30~80years old, 513 women living in Seoul and Kyunggi area who participated in 2011 KNHANES. The study subjects were divided into three BMD groups; normal, n = 259 (50.4%), osteopenia, n = 169 (32.9%), and osteoporosis, n = 85 (16.7%). Average height and weight and fat free mass decreased with a decrease in BMD. Average BMD of normal, osteopenia, osteoporosis were 0.87, 0.79, $0.70g/cm^2$, and T-score were 0.42, -0.66, -1.62, respectively. Higher systolic blood pressure, alkaline phosphatase, and triglyceride were significantly associated with a decrease in the BMD. The rates of hypertension were significantly increased from normal to osteoporosis. i.e. 18.5% in normal, 34.3% in osteopenia and 63.5% in osteoporosis. Average nutrientintakes such as protein, fat, calcium, phosphorus, iron, sodium, potassium, vitamin A, vitamin B, vitamin B2, and vitamin C were significantly lower in subjects with lower BMD.n. Average calcium intake of normal, osteopernia and osteoporosis were 528.50, 416.96, 389.56 mg, respectively. There were significant negative correlations between calcium, phosphorus and age, systolic blood pressure, triglyceride. Also, there were negative correlation systolic blood pressure (incomplete sentence). In this study, we found low BMD according to low calcium intake increase the risk of osteoporosis and hypertension rather than sodium intake, also calcium intake decreased with increase age. Therefore, in order to prevent osteoporosis and hypertension, subjects need to be educated regarding the importance of calcium nutrients in diet.

• Economic and Environmental Geology
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• v.32 no.5
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• pp.537-544
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• 1999

In mineral exploration, there are many data sets which need to be created, processed and analyzed in order to discover a favorable mineralized zone. Recently, with Geographic Information System (GIS), such exploration data sets have been able to be systematically stored and effectively processed using computer technologies. In this study, most exploration data sets were first digitized and then rasterized. Furthermore, they were integrated together by using fuzzy set theory to provide a possibility map toward a target hypothesis. Our target hypothesis is "there is a skarn magnetite deposit in this study" and all fuzzy membership functions were made with respect to the target hypothesis. Test area is extended from 37:00N/l28:30E to 37:20N/I28:45E, approximately 20 km by 40 km. This area is a part of Taebaeksan mineralized areas, where the Sinyemi mine, a skarn magnetite deposit, is located. In final resultant map, high potential or possibility area coincides with the location of the Shinyemi mine. In this regard, we conclude the fuzzy set theory can be effectively applied to this study and provides an excellent example to define potential area for further mineral exploration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.257-264
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• 2013

The purpose of this study was to examine the weight bearing exercise effect on bone mineral density(BMD) and upper extremity function in the female stroke patients. The subject were 24 female stroke patients, randomly assigned to a weight-bearing group(n=12, WBG) and a control group(n=12, CG). The experiments were conducted for three times per week for eight weeks, radial BMD and MFT(Manual Function Test) of both groups were measured before the experiments and eight weeks after the beginning of the experiments. In conclusion, it was found that there was a significant increase of the weight-bearing group radial BMD and MFT score, The results suggest that weight bearing exercise is effective in improving BMD and upper extremity function, thus, can be utilized in stroke rehabilitation.

• Applied Microscopy
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• v.51
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• pp.17.1-17.10
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• 2021

Our previous study on the binding activity between Cel5H and clay minerals showed highest binding efficiency among other cellulase enzymes cloned. Here, based on previous studies, we hypothesized that the positive amino acids on the surface of Cel5H protein may play an important role in binding to clay surfaces. To examine this, protein sequences of Bacillus licheniformis Cel5H (BlCel5H) and Paenibacillus polymyxa Cel5A (PpCel5A) were analyzed and then selected amino acids were mutated. These mutated proteins were investigated for binding activity and force measurement via atomic force microscopy (AFM). A total of seven amino acids which are only present in BlCel5H but not in PpCel5A were selected for mutational studies and the positive residues which are present in both were omitted. Of the seven selected surface lysine residues, only three mutants K196A(M2), K54A(M3) and K157T(M4) showed 12%, 7% and 8% less clay mineral binding ability, respectively compared with wild-type. The probable reason why other mutants did not show altered binding efficiency might be due to relative location of amino acids on the protein surface. Meanwhile, measurement of adhesion forces on mica sheets showed a well-defined maximum at 69±19 pN for wild-type, 58±19 pN for M2, 53±19 pN for M3, and 49±19 pN for M4 proteins. Hence, our results demonstrated that relative location of surface amino acids of Cel5H protein especially positive charged amino acids are important in the process of clay mineral-protein binding interaction through electrostatic exchange of charges.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.5
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• pp.592-595
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• 1993

Mineral compositions in various ginseng, which was grown in different region, different age, were analyzed by atomic absorption spectrophotometer. $Mn^{++}$ content in ginseng of five years old was four times higher than that of two years old, suggesting that the amount of $Mn^{++}$ would be increased as they are cultivated. The content of phosphate in the various ginseng did not show much difference, whereas that of $Ca^{++},\;Mn^{++}$ did. Korean red ginseng revealed much higher in $Mn^{++}$ content than that of others investigated. When the amount N was compared, San Chi, Chinese ginseng was significantly lowered. Korean red ginseng of 100g contains highest phosphate ion of 328.3mg.