• Journal of the Korean Ceramic Society
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• v.36 no.10
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• pp.1080-1086
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• 1999

Mullite/zirconia composite was synthesized by adding zirconia and Zircon to mixture of Hapcheon kaolin(grade pink A) and aluminium nitrate salt in order to enhance strength of the mullite specimens. Kaolin and aluminium nitrate salt was mixed milled and calcined at 100$0^{\circ}C$ and then 5wt% mullite seed was added to increase mullite content. The influence of the additives(ZrO2 and ZrSiO4) and sintering temperature on the strength of the sintered specimens was investigated. The flexural strength of the specimens containing 10wt% zirconia was enhanced from 150MPa without the additive up to 300MPa after heat treatment at 156$0^{\circ}C$ In the case of addition of 15wt% zircon the strength of the specimens systhesized at 1$600^{\circ}C$ was 225 MPa.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.131-134
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• 2004

Several physical and chemical methods have been used for remediation contaminated by oils. However the cost was very high and secondary pollution rose during treating. The purpose of this study was to comprision TPH (total petroleum hydrocarbon) removal from artificially contaminated soil by diesel with and without seeding anaerobic digested sludge. After 120 days of overall at 35$^{\circ}C$, removal efficiency of TPH with seeding sludge was 2-3 times higher than blank. Also, the more amount seeding sludge, TPH removal efficiency and CH$_4$ content more obtained. It was sad that seeding of anaerobic digested sludge was a good method for enhancing TPH removal efficiency without increasing operating cost. Sulfate, nitrate-reducing, methanogenic condition were evaluated for alkane, isoprenoid as target contaminated soil.

• The Korean Journal of Mycology
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• v.44 no.2
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• pp.100-102
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• 2016

Ergothioneine is a natural compound with strong antioxidant properties. In this study, the effects of different nitrogen sources including ammonium nitrate, ammonium sulfate, sodium nitrate, and histidine in sawdust media were investigated to enhance ergothioneine contents in Shiitake (Lentinula edodes) fruit bodies. The addition of 0.2% ammonium sulfate in the growth media showed the highest enhancement of ergothioneine content in shiitake fruit bodies which was 1.7-fold higher than the control. On the other hand, histidine, a building block of ergothioneine decreased the concentration of ergothioneine significantly. Our results demonstrate that the cultivation of shiitake in sawdust media with suitable nutrients was effective to enhance its ergothioneine contents.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.355-358
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• 2005

Nitrate-selective ion exchange resins involving bulky trialkyl amino as functional group were synthesized by the reaction of chloromethylated polystyrene-divinylbenzene copolymer and the corresponding tripropylamine in ethanol. Fundmental properties such as bulk density, water content, effeative diameter, uniformity coefficient, appearance index, exchange capacity and particle size distribution were fully measured. The synthesized resins appeared to be good for nitrate selection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.446-451
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• 2008

The growth of Porphyridium cruentum and its porphyran polysaccharide production were measured as functions of light intensity, temperature, light quality (fluorescent, blue, red, and green) and nitrate concentration. The optimum light intensity, temperature, and nitrate concentration for the growth of Porphyridium cruentum and for its polysaccharide production were 1,400 lx, $25^{\circ}C$, and 0.03%, respectively. The maximum cell concentration and polysaccharide content under the optimum conditions were 1.95 and 0.23 mg/mL, respectively. Light quality did not influence growth or polysaccharide production. The best results for growth and polysaccharide production were obtained using fluorescent light.

• Journal of the Korean Ceramic Society
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• v.34 no.11
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• pp.1113-1120
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• 1997

The 2, 4, 6 and 8mol% Y2O3 doped-ZrO2 powders (20 kinds) with the addedtion of Al2O3 upto 8wt% were prepared by coprecipitation method using the zirconium oxyacetate, yttrium chloride and aluminum nitrate as starting materials. The coprecipitated powders were characterized by XRD, TG-DTA, FT-IR and SEM. The sintering properties of zirconia-alumina composites prepared by 2YSZ and 8YSZ powders containing various Al2O3 contents were also investigated. With increasing the yttria stabilizer contents, the amount of exothermic heat for zirconia crystallization decreased. And it was confirmed that the crystallizing temperature of coprecipitated zirconia powders increased and the crystallization process occurred in a wide temperature range, as Al2O3 content increased in 8YSZ.

• Journal of Nutrition and Health
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• v.7 no.1
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• pp.25-29
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• 1974

In order to help food habits of Korean, major foods of side dishes in Korean foods were analyzed by Mohr's Silver Nitrate Method. The kinds of foods were Kanchang (Sa)Sauce) Kochuchaag(Redpepperbean paste), Doeuchang(Soy bean Paste) and Kimchies, and selected into 3 areas in Korea; Seoul (city area), Kyung Puk Province (Fishery area) and Chun-Puk Province (Farming area). The results are as follows; Average NaCl content of Kan-chang is 26.04g/dl ranged from 24.27 to 28.22g/dl and among them Farming area is the highest content. In Ko-chu-chang, average content is 11.36g% ranged from 10.77 to 11.60g%. Doen-chang has an average 15.89% ranged from 13.28 to 18.54g% and in Kimckies they were resulted 3.36g%.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.3
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• pp.3-8
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• 2006

The fractions of nitrogen were investigated in the soils of reclaimed and natural tidelands of southwest coastal area of Korea. The content of total-N varied to ranged form 619 to 5,534 mg/kg dry weight with a mean value of 1,857 mg/kg. The order of different fractions of nitrogen was as follows: Acid non-extractable-N > uncounted-N > acid extractable-N > ammonia-N > nitrate-N. The content of ammonia-N, acid extractable-N, and acid non-extractable-N showed highly negative correlations with pH. The content of acid extractable-N and ammonia-N showed highly positive correlation with clay content.

• KSBB Journal
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• v.5 no.4
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• pp.347-353
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• 1990

The effects of nutrients and cell aggregate size on the cell growth of D. carota and the biosynthesi of carotenoid were investigated. Highest carotenoid content was obtained with sucrose as a carbon source and the equal ratio of ammonium to nitrate. High phosphate concentration stimulated the carotenoid biosynthesis in D. corota. 2,4-D inhibited the cell growth but stimulated the specific carotenoid content at high concentration. By modifying the medium composition based on these findings, three times higher specific carotenoid content and 2.5 times higher total carotenoid content were obtained as compared with the results obtained with basic MS media. Biosynthesis of carotenoid was found to be affected by cell aggregate size; high carotenoid production was obtained from the large aggregated cells resulted from high sucrose concentration.

• Membrane and Water Treatment
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• v.2 no.1
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• pp.25-37
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• 2011

PES UF membranes containing silver were prepared to impart antibacterial properties for waste water treatment. Asymmetric membranes for antibacterial application were prepared from polyethersulfone (PES) and silver nitrate ($AgNO_3$) (PES/$AgNO_3$=15/2 by weight) solution in N-Methyl-2-pyrrolidone (NMP) via simple wet phase inversion technique. These membranes were characterized by polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) of different molecular weights (1000 ppm in water) at room temperature and on operating pressure of 5 bars. It was observed that the water flux of PES-$AgNO_3$ membrane is slightly lower than virgin PES but still increased linearly with the increment of pressure applied. The morphology of the resulting membranes was examined using Field-Emission Scanning Electron Microscope (FESEM) coupled with Energy Dispersive Spectroscopy (EDS). Elemental analysis using EDS proved that silver is successfully loaded on the membrane surfaces. Due to the success of loading silver on membrane surfaces, antibacterial activities were evaluated via agar diffusion method against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) culture. By incorporating 2 wt% of silver nitrate, PES-$AgNO_3$ showed significant inhibition ring on both E.coli and S.aureus. Filtration of E.coli solution (OD 0.31) showed satisfactory rejection data with ~100% inhibition growth after 24 hours incubation at $37^{\circ}C$. Resultant membranes also exhibit better tensile strength (compared to virgin PES) up to 71% may be due to the suggested interactions. The residual silver during fabrication was measured using ICP-MS and result showed that the residual silver content of PES-$AgNO_3$ membrane was only ~1% of the original silver added in the polymer solution. These studies have shown that PES-$AgNO_3$ UF membranes are potential in improving the filtration in water treatment.