• Transactions of the Korean hydrogen and new energy society
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• v.26 no.1
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• pp.8-14
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• 2015

In this study, the model biomass was used for hydrogen production by supercritical water gasification (SCWG). Model biomasses were glycerol, glycine, lignin and cellulose. The feed concentration was set to 1 wt%. Experiments were conducted in a reactor at $440^{\circ}C$ and above 26.3 MPa for 30 min. The effects of catalysts such as alkali metal salt ($K_2CO_3$ and $Na_2CO_3$) and transition metal salts ($Ni(NO_3)_2$, $Fe(NO_3)_3$ and $Mn(NO_3)_2$) on the gasification were systematically investigated. No tar or coke was observed in all experiments. The results showed that the gasification efficiency increased with various catalysts. For the cellulose and glycerol, all catalysts were effective for the promoted $H_2$ production compared with no catalyst. The significant decrease of $H_2$ production compared with no catalyst was observed with $Na_2CO_3$ and $Fe(NO_3)_3$ for glycine and lignin. respectively. The highest H2 production, 1.24 mmol was obtained for glycerol-SCWG with $Mn(NO_3)_2$. Conclusively, the addition of $Mn(NO_3)_2$ enhanced all model biomass gasification efficiency and increased the hydrogen production promoting the supercritical water reaction.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.10
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• pp.1469-1474
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• 2002

This study was designed to evaluate the influence of a single or double dose of Fe dextran with organic trace mineral supplementation on the performance of piglets from dams fed diets with either inorganic (ITM) or organic trace minerals (OTM). It also determined the effect of the source of the trace minerals on the reproductive performance of sows. The trace mineral premixes were prepared using metal proteinates and the corresponding inorganic salts for the OTM and the ITM, respectively. Each mineral premix provided 100 ppm Fe/175 ppm Fe, 35 ppm Cu/170 ppm Cu, 90 ppm Zn/120 ppm Zn, and 40 ppm Mn/35 ppm Mn when added at 0.20% in sows /weaned pigs' diets, respectively. The first dose of Fe dextran was administered to piglets at 3 d and the second dose at 10 d after birth. One dose of Fe dextran supplied 100 mg of Fe. A total of 16 gestating sows (Landrace${\times}$Yorkshire) in parities 2 to 4 were randomly allocated to four treatments: 1) diet with ITM/one dose of Fe dextran to piglets, 2) diet with ITM/two doses of Fe dextran to piglets, 3) diet with OTM/one dose of Fe dextran to piglets, and 4) diet with OTM/two doses of Fe dextran to piglets. The total born alive, weaned, body weight at birth and at weaning were not affected by the sow's dietary treatment. Although organic trace mineral supplementation tended to increase the milk Fe content (p<0.10) at 7 d postpartum, piglets in all treatments performed equally from birth to weaning. The double doses of Fe dextran neither improved the average daily gain (ADG) nor influenced the survival of piglets from birth to weaning (21 d). Results suggest that a single dose of Fe dextran given to suckling pigs is adequate to sustain their needs for growth throughout the lactation period (21 d). Furthermore, there was a 21% improvement in both the ADG and the average daily feed intake (ADFI) (p<0.05) in weaned pigs fed diets with OTM. Cu and Fe in the liver (p<0.01), and Zn in both the bone (p<0.01) and the serum (p<0.01) were higher in piglets fed OTM than in those fed ITM. It would be concluded that single dose of Fe dextran administration with organic trace mineral supplementation show similar growth performance compared to 2 dose Fe dextran administration with inorganic mineral supplementation in young pigs.

• Economic and Environmental Geology
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• v.42 no.3
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• pp.207-216
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• 2009

In this study, water quality variation in borehole groundwaters and surface leachate waters were investigated on a seasonal sampling and remote monitoring basis within the waste impoundments at the Geopung mine site where previous rehabilitation measures were unsuccessful to prevent acidic drainage. All groundwaters were typical acidic drainage with acidic pH (3.3${\sim}$4.6) and high TDS (338${\sim}$3330 mg/L) values during the dry season, but increases in metal contents (TDS 414${\sim}$4890 mg/L) and decrease of pH (2.7${\sim}$3.6) were observed during the rainy season. Surface leachate waters showed a similar pattern in water quality variation. Surface runoff waters during rain events had acidic pH (3.0${\sim}$3.4) through direct reactions with waste rocks. Good correlations were found between major and trace elements measured in water samples, but no significant seasonal variation in chemical compositions was shown except relative changes in contents. It can be suggested that dissolution of soluble secondary salts caused by flushing of weathered waste rocks and tailings directly influenced the water quality within the waste impoundments. Increases in acid and metal concentrations and their loadings from mine wastes are anticipated in the rainy season. More appropriate cover systems on waste rocks and tailings necessitate consideration of more extreme conditions in the study mine.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1442-1445
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• 2000

This study was carried out to investigate the contents of minerals and heavy metals in the sea salts of Korean products and imported products. NaCl was major component, which ranged from $80.31{\sim}89.84%$ for Korean products and from $91.59{\sim}97.66%$ for imported products. Minerals and heavy metals of Korean products and imported products were analyzed with ICP-AES and AAS, respectively. Mineral contents of K and Mg in Korean products were relatively higher than those in imported ones, but no significant differences were found for heavy metals between them.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.328-332
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• 2007

This study was conducted to investigate the effects of high concentrations of salts in soil on the growth, yield, quality, photosynthetic rate, and mineral uptake of tomato ('House Momotaro') in pot cultivation. The growth of tomato such as plant height, top plant weight and root weight decreased as the concentrations of salts in soils increased. Yield decreased by 31% and 41% in EC 5.0 and $7.5dS{\cdot}m^{-1}$, respectively compared with the salt concentration of EC $1.5dS{\cdot}m^{-1}$. Yield reduction was caused by low mean weight and number of fruit if at high salt concentration in soil, and affected by low photosynthetic rate and water potential in leaf, The rate of blossom-end rot was highest (16.7%) in EC $7.5dS{\cdot}m^{-1}$ and increased as the concentrations of salts in soils increased. The contents of soluble solids and titratable acids showed a tendency to increase with increasing the concentrations of salts in soils. Photosynthetic rate, water potential and stomatal conductance in leaf decreased as the salt concentration in soil increased. The higher the salt concentration in soil, the lower the mineral uptake such as T-N, P, K, Ca and Mg but, the higher the content of Na.

• KSBB Journal
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• v.22 no.5
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• pp.322-327
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• 2007

Mineral salts in medium usually profoundly influence microorganism growth and protein synthesis. In order to produce microbial transglutaminase (MTG) with a high yield from Streptoverticillium mobaraense, we screened the minerals $CaCl_2,\;CoCl_2,\;FeSO_4,\;ZnSO_4,\;MnSO_4\;and\;CuSO_4$ for MTG fermentation. The results indicated that appropriate $FeSO_4$ concentrations could significantly promote cell growth and stimulate the production of MTG. With 15 mg/L of $FeSO_4$ added to medium, 58% improvements were noted in MTG productivity (2.24 U/mL). NaCl, $CaCl_2,\;and\;CoCl_2$ enhanced MTG productivity by less than 15%, and the optimal concentrations were determined as 1 g/L, 2 g/L, and 30 mg/L respectively. Furthermore, it was determined that 7.5 mg/L of $ZnSO_4$ in medium could augment MTG productivity by 20% and induce the stationary phase for MTG production to a period 24 hr earlier. This basic and novel discovery should result in the development of a good complement to the previously defined culture media for MTG fermentation.

• Resources Recycling
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• v.15 no.2 s.70
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• pp.32-36
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• 2006

Magnesium has been used as light and functional material, and its demand is increasing as a material for automobile engine and for mobile phone or notebook PC case. Fused salt electrolysis and thermal reduction are regarded as main methods for the extraction of magnesium, and choice for the method is firstly according to raw material. In this study, magnesium metal is obtained by an electrolysis of magnesium chloride. Two types of fused salt mixtures were used as electrolyte and electrolyzed at 7V with a graphite anode having the same depth, and their results were compared with each other. A mixed salt of $KCl/NaCl/MgCl_2$ was the more effective than $KCl/NaCl/CaCl_2/CaF_2/MgCl_2$ in current efficiency through the experiments at $760^{\circ}C$. Purity of the prepared magnesium metal was above 98%. Some basic data for scale-up of the magnesium electrolysis equipment, which would be necessary for a commercialization, could be obtained.

• Journal of the Mineralogical Society of Korea
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• v.20 no.2 s.52
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• pp.125-134
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• 2007

This study has been carried out in order to examine the precipitation characteristics of Fe, Mn and Al ions in coal mine drainage before removing heavy metals by using the froth flotation method. The removal rate of Fe(III), Mn(II) and Al(III) within 1 h accounted for over 99% in pH 5.0, 10.0, and $6.0{\sim}9.0$ respectively, and residual concentrations of which were under $1mgL^{-1}$. When sodium oleate as a collector was added to the solution of Fe, Mn, and Al ions, insoluble salts was not formed by the reaction of heavy metal and sodium oleate. So, we must remove the metals from coal mine drainage by using not the ion flotation method, but the precipitation flotation method

• Journal of Life Science
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• v.8 no.3
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• pp.333-338
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• 1998

Productivity of alkaline proteinase from Yarrowia lipolytica 504D was investigated. For the production fo the enzyme, hemoglobin was the best nitogen source, however, casein and skim milk were also good. All carbon sources inhibited strongly the producitivity of the enzyme. Yeast extract increased the productivity of the enzyme to 220%, but almost mineral salts except monovalant ions decreased it. Based on these results, optimal medium was composed of 1.2% casein, 0.2% glucose, 0.16% yeast extract, and 0.1% ammonium sulfate. the best condition for the production of the enzyme was observed at pH 9 and $20^{\circ}C$ for 42 hours.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.253-256
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• 2003

In batch culture of A. pullulans HP-2001, maximal production of pullulan was 57.90 g/l at 96 hr. The maximal production of pullulan with 76.55 g/l occurred when substituted solution was 10% (w/v) sucrose, 0.25% (w/v) yeast extract and mineral salts. The maximal production of pullulan was 75.00 g/l with a dilution rate of $0.015\;h^{-1}$. Productivity of pullulan in the continuous culture fed with the fresh medium was higher than that fed with the fresh medium without nitrogen source.