• Journal of the Korean Ceramic Society
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• v.18 no.4
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• pp.247-256
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• 1981

Silica bricks had been in arc-furnace roofs of various sizes and steelmaking practices. The resulting materials were examined with reference to mineral and chemical changes. Silica bricks develope definite zones while in service. These zones represent a concentration gradient through the brick that results from the thermal gradient across the brick and from the furnace atmosphere. There are major brick losses by spalling as well as by melting of the hot-face surface in an iron-oxide rich liquid.

• Journal of the Korean Ceramic Society
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• v.33 no.11
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• pp.1276-1284
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• 1996

Ultrafine calcim carbonate powders with the size of 0.05~0.1 ${\mu}{\textrm}{m}$ and the calcite phase were prepared by the nozzle spouting method which was conducted by spouting calcium hydroxide slurry in reactor filled with CO2 gas. Well dispersed ultra-fine particles were synthesized in condition of high Ca(OH)2 concentration of the slurry ( 0.5wt%) synthesized calcium carbonate powder was shown the large particle size with agglo-meration.

• Korean Journal of Metals and Materials
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• v.46 no.12
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• pp.823-829
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• 2008

The solvent extraction process for the recovery of vanadium from leaching solution of SCR(selective catalytic reduction) spent catalyst was investigated by using Alamine336 as an extractant. The effects of experimental conditions, such as initial pH and concentration of sulfate ion, and ammonia concentration of stripping solution were studied. The extraction percentage of vanadium were increased with the increase of initial pH of leaching solution and decreased with the increase of sulfate ion. More than 99% of vanadium in leaching solution were extracted and stripped at the A/O ratio of 1.0 in 2 stages. On the basis of these results, an optimum solvent extraction process which vanadium was effectively recovered from SCR spent catalyst was proposed.

• Journal of Plant Biology
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• v.34 no.2
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• pp.151-158
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• 1991

A new technique involving gamma-spectrometry was used to determine the effects of pollination on mineral uptake in petals, ovaries and leaves of tulips and daffodils. A gamma-emitting radionu'::lide solution containing selenium-75, cesium-137, manganese-54, and zinc-65 was applied to the roots of tulips and daffodils growing in water. Mineral uptake was monitored in plant parts over a 24 day period. Pollinated tulip flowers showed a rapid withdrawal of minerals from the petals and an increase in ovary mineral content, while such a source-sink relationship was not established in daffodils. In both species, the concentration of most minerals in petals and ovaries declined prior to abortion of the plant part. The roots and bulbs of the plants contained the vast majority of the labeled minerals. This study demonstrated a possibility that certain plant parts could be isolated and monitored for mineral uptake over time without destruction.uction.

• Journal of Nutrition and Health
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• v.36 no.4
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• pp.359-367
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• 2003

The purpose of this study was to examine the impact of soy protein and soy isoflavones on bone and mineral density in young female Sprague-Dawley rats. Fifty eight rats (body Weight 75 $\pm$ 5 g) were randomly assigned to one of four groups, consuming casein, soy protein concentrate, soy protein isolate (57 mg isoflavones/100 g diet) or casein added isoflavones (57 mg isoflavones /100 g diet). All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur on 3, 6, 9 weeks after feeding. The serum and urine concentrations of Ca and P were determined. Diet did not affect weight gain and mean food intake. Food efficiency ratio was lower In soy protein groups. The serum concentration of Ca and P were not changed by soy protein and isoflavones. Urinary Ca and P excretion were not significantly different. Spine BMD was significantly increased by soy protein isolate on 3 and 6 weeks after feeding. Femur BMD was significantly increased in the groups of soy protein isolate and isoflavones adding on after 9 weeks. Therefore, soy protein with rich isoflavones may be beneficial on spine and femur BMD increasement in growing female rats.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.334-337
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• 2004

Groundwater chemistry in Namwon area, Korea, was investigated to understand the contribution of geochemical processes on groundwater chemistry. For this study, a total of 279 groundwater samples were collected from 93 wells distributed over the study area. Higher concentrations of major ions are generally encountered in the shallow alluvial wells, suggesting that these chemicals are originated from the surface contamination sources. Mass balance analysis based on reaction stoichiometry reveals that the water chemistry is regulated by three major chemical processes: weathering of silicate/ carbonate minerals, input of C1/SO$_4$ salts, and nitrate generating processes. The results show that mineral weathering is the most dominating factor regulating the groundwater chemistry. However, the groundwaters with the higher salt concentration indicate the larger mineral weathering effect, suggesting that some part of the mineral weathering effect is also associated with the anthropogenic activities such as limes applied to the cultivated lands, carbonates (CaCO$_3$) in the cement materials.

• KSBB Journal
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• v.13 no.6
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• pp.644-648
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• 1998

In the production of a low cost bacterial insecticide, it is important to produce a high spore concentration using low price substrates. Experiments were carried out to investigate the effects of the addition of mineral salts and glucose, and of dissolved oxygen concentration on the cell growth and spore formation of Bacillus thuringiensis var aizawai using a cheap wheat and soybean meal in the batch culture. The maximum viable cell number was 1.2${\times}$109 CFU/mL at 12 hr culture and spore yield was 54.2% at 74 hr culture using an industrial medium containing 20 g/L wheat meal and 30 g/L soybean meal under 1.0 vvm aeration and 200 rpm agitation. The cell growth and the spore formation were not enhanced by the addition of mineral salts in industrial medium, whereas th addition of 10g/L glucose decreased the cell growth and spore formation. We could obtain a maximum viable cell number of 2.2${\times}$109 CFU/mL and spore number of 1.9${\times}$109 CFU/mL at the dissolved oxygen concentration of 60% of saturation. The spore concentration was enhanced approximately by 2 times as compared to the dissolved oxygen concentration of 50%. In the bench-scale culture, the maximum viable cell and spore number were 2.5${\times}$109 CFU/mL, and 2.2${\times}$109 CFU/mL, respectively under 1.0 vvm aeration and 400 rpm agitation. The spore yield was 88% based on the maximum viable cell number. As a result, it was confirmed that the production of high spore concentration could be obtained by a bench-scale culture using an industrial medium.

• Resources Recycling
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• v.22 no.6
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• pp.48-54
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• 2013

The methods to separate and remove copper in the mixed solution ((399 ppm Cu, 208 ppm Fe, 15.3 g/L Ni, 2.1 g/L Co) with nickel, cobalt and iron were investigated. With hydroxide precipitation method, copper and iron ions were completely precipitated and removed from the solution at pH 7 while some nickel and cobalt also were precipitated. 99.75% copper could be precipitated and removed as copper sulfide from the solution with adding $Na_2S$ (1.25 w/v concentration) of 2 times equivalent of Cu at pH 1. Copper was selectively absorbed on TP 207 ion exchange resin at equilibrium pH 2.0 and could be eluted from copper-loaded resin using 5% $H_2SO_4$.

• Geosciences Journal
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• v.22 no.6
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• pp.921-938
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• 2018

The Motzfeldt intrusions in the Gardar Province, southern Greenland, split into syenitic plutonic and hypabyssal rocks, in which the latter include ring dykes and sheet intrusions. Sheet intrusions, considered as the source for rare earth elements (REE) and high field strength elements (HFSE), comprise sheets of peralkaline microsyenite (SPM), syenitic pegmatite (SP), and peralkaline microsyenite (PM). SP exhibits extremely high concentrations of REE and HFSE, which are positively correlated with increasing alkalinity from early towards late intrusion, caused by magmatic processes. In contrast, some of the SPM and PM are also significantly enriched in REE and HFSE, caused by post-magmatic fluids. The REE- and HFSE-rich phases in SP consist mainly of zircon and allanite with smaller amounts of pyrochlore in pseudomorph from the inferred eudialyte, whereas some of the PM and SPM consist of pyrochlore, REE-carbonate, and zircon in the matrix. The zircon grains in the Motzfeldt Sø Formation (MSF) syenite occur in interstitial spaces, exhibiting an association with magnetite and a bipyramidal form in texture. They are characterized by a highly fractured and embayed rim. Zircons from PM and SP are clearly enriched in Fe, Al, Ca, Na, Y, P, Hf, Y, P, Nb, Ta, and REE, and are depleted in Zr and Si in comparison with magmatic zircon. They also show a clear trend of higher LREE/HREE and $Eu/Eu^{\star}$ ratios, and lower $Ce/Ce^{\star}$ ratios, which define them as typical hydrothermal zircons. In contrast, zircons from the MSF syenite show a relatively lower LREE/HREE ratio and Eu and Ce anomalies of a similar magnitude compared with those from SP and PM. The occurrence and mineral composition of the zircon suggest that post-magmatic fluids have played an important role in the remobilization of REE and HFSE as well as the primary concentration of REE and HFSE, caused by magmatic processes.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.133-138
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• 2002

This study was conducted to investigate the effece of NaCl concentrations on the growth, photosynthetic rate and mineral uptake of tomato, red pepper, and egg Plant in Pot culture. The growth such as plant height, plant fresh and dry weight, root fresh and dry weight and dried matter rate was decreased as NaCl concentrations were increased. Specially, the growth inhibition of tomato and egg plant was shown at over 40 mM NaCl, and that of red pepper at 20 mM NaCl. Yield of tomato and egg Plant was reduced at over 20 U NaCl, that of red pepper at over 10 mM NaCl. Yield reduction was affected by the number of fruit at low concentration and by mean weight and number of fruit at high concentration. Photosynthetic rate, water potential and stomatal conductance were decreased as NaCl concentrations were increased. The higher the concentration of NaCl, the lower the mineral uptake such as T-N, P, K, Ca and Mg, however, the higher the content of Na and Cl.