• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1093-1102
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• 2009

This study was focused on analyse Nonpoint source characteristics from Flat slope field and Steep slope field. We performed Storm-water monitering for obtain flow data and concentration data. Totally, eleven times Event was occurred. We calculated EMC(Event Mean Concentration) and Pollutants Loads using data we obtained. As a result, steep slope field has more discharge than flat field. SS value, one of the water quality contents, has largest variation and T-N has least variation. There is runoff differences even though events has same rainfall. We assume that not only amount of Rainfall, but also Rainfall Duration Times, Intensity, Number of Previous Non-precipitation days can affect to Run-off.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.1
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• pp.1-8
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• 1998

Biomass of non-living brown seaweed Sargassum fluitans pretreated by different methods is capable of taking up more than $10\%$ (11 meq/g) of its dry weight in aluminum at a pH of 4.5. It is indicated that the biomass sequestered the aluminum in the form of polynuclear aluminum species. The fraction of $Al(OH)_3$ Precipitated in the aluminum nitrate solution without biomass at pH 4.5 increased as the Al concentration increased. Aluminum-alginate complex precipitated in the solution as alginate was partially released from the biomass. External colloidal precipitate occurring in native and protonated S. fluitans biomass sorption systems caused a significant difference in Al sorption isotherms determined by standard and desorption methods, respectively, Sodium ions added for pH adjustment were not sorbed at all in the presence of aluminum ions.

• Journal of Powder Materials
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• v.10 no.5
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• pp.310-317
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• 2003

Two-component ceramic (alumina-zirconia) composites were fabricated by a soft-solution process in which polyethylene glycol (PEG) was used as a polymeric carrier. Metal salts and PEG were dissolved in ethyl alcohol without any precipitation in 1:1 volume ratio of alumina and zirconia. In the non-aqueous system, the flammable solvent made explosive, exothermic reaction during drying process. The reaction resulted in formation of volume expanded, porous precursor powders by a vigorous decomposition of organic components in the precursor sol. The PEG content affected the grain size of sintered composites as well as the morphology of precursor powders. The difference of microstructure in sintered composite was attribute to the solubility and homogeneity of metal cations in precursor sol. At the optimum amount of the PEG polymer, the metal ions were dispersed effectively in solution and a homogeneous polymeric network was formed. It made less agglomerated particles in the precursor sol and affected on uniform grain size in sintered composite.

• Journal of Powder Materials
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• v.9 no.5
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• pp.346-351
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• 2002

Pure and fine, two-component titanate powders (barium titanate, calcium titanate etc.) were synthesized by an ethylene glycol method. Titanium isopropoxide and other metal ionic salts were dissolved in liquid-type ethylene glycol without any precipitation. In non-aqueous system, the amount of ethylene glycol affected the solubility and homogeneity of metal cation sources in the solution. At the optimum amount of the polymer, the metal ions were dispersed effectively in solution and a homogeneous polymeric network was formed. Most of the synthesized powders had sub-micron or nano-size primary particles after calcination and the agglomerated calcined powders were easily ground by ball milling process. All synthesized titanate powders had stable crystallization behavior at low temperature and high specific surface area after ball milling. The crystallization behavior and the microstructures of the calcined powders were affected on the ethylene glycol content.

• Journal of Applied Biological Chemistry
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• v.54 no.2
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• pp.84-88
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• 2011

Edestin, a major hempseed storage protein from Cheungsam, was isolated to apparent homogeneity by acid precipitation and gel filtration chromatography. The native molecular weight of purified edestin was approximately 300 kDa by Sephacryl S-300 gel filtration. Upon adding 2-mercaptoethanol, the isolated edestin of 56.7 kDa on the non-reduced sodium dodecyl sulfate polyacrylamide gel was converted into subunits, suggesting that the protein might be composed of subunits linked by disulfide bond. Cheungsam edestin was rich in essential amino acids and it has 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity. The results suggest that Cheungsam edestin might be utilized as a superior antioxidative nutrient.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.437-440
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• 2008

In recent years, pollution load calculation has become a topic for research that resulted in the development of numerous GIS modeling methods. The existing pollution method for nonpoint source (NPS) can not be indentified and calculated the amount of the pollution precisely. This research shows that the association of typical pollutant concentrations with land uses in a watershed can provide a reasonably accurate characterization of nonpoint source pollution in the watershed using Expected Mean Concentrations (EMC). The GIS based pollution assessment method is performed for three pollutant constituents: BOD, TN, and TP. First, the runoff grid by means of the precipitation grid and runoff coefficient is estimated. Then, the NPS pollution loads are calculated by grid based method. Finally, the final outputs are evaluated by statistical technique. The results illustrate the merits of the approach. This model verified that GIS based method of estimating spatially distributed NPS pollution loads can lead to more accurate representation of the real world.

• Journal of the Korean Society for Heat Treatment
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• v.2 no.4
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• pp.19-26
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• 1989

Fundmental fatigue crack propagation tests with C-T type specimens were conducted at various load ratios (R) such as 0.1, 0.3 and 0.5 in T6 and Thermomechanically treated (TMT) conditions of 7039 Al alloy. Better mechanical properties from monotonic test as well as fatigue crack propagation were obtained by TMT process owing to uniform distribution of fine microstructures and non-existence of precipitation free zone (PFZ). Through the measurement of Kop and ${\Delta}K$ at various R the concept of effective stress intensity factor range ratio, U was reviewed to asses the load ratio effect on fatigue crack propagation. A relationship between U and variables such as ${\Delta}K$ and R was obtained empirically. This may enable us to predict ${\Delta}K_{eff}$ that is of critical importance for prediction of fatigue crack propagation rate.

• Economic and Environmental Geology
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• v.29 no.4
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• pp.471-481
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• 1996

Clay mineral geothermometry using sericites and chlorites in Bobae sericite mine reveals that these clay minerals formed at relatively high temperature. It appears that sericites formed at around $200{\sim}350^{\circ}C$ and chlorites formed at around $250^{\circ}C$. X-ray diffraction study of these minerals reveals that sericite $2M_1$ type and chlorite IIb type are dominant phases. Both polytypes indicate that the precipitation temperatures of these minerals shows fairly good agreement with the estimated temperature by clay mineral geothermometry. The Bobae sericite mine was formed at relatively higher temperature than several non-metal ore deposits occurred in the southern part of Korea.

• Economic and Environmental Geology
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• v.29 no.4
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• pp.447-454
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• 1996

Clay mineral geothermometry using sericites and chlorites in Bobae sericite mine reveals that these clay minerals formed at relatively high temperature. It appears that sericites formed at around $200{\sim}350^{\circ}C$ and chlorites formed at around $250^{\circ}C$. X-ray diffraction study of these minerals reveals that sericite 2M, type and chlorite lib type are dominant phases. Both polytypes indicate that the precipitation temperatures of these minerals shows fairly good agreement with the estimated temperature by clay mineral geothermometry. The Bobae sericite mine was formed at relatively higher temperature than several non-metal ore deposits occurred in the southern part of Korea.

• Journal of Environmental Science International
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• v.8 no.6
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• pp.645-652
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• 1999

In order to simulate and investigate the major characteristics of El Nino/Southern Oscillation(ENSO) and Madden Jullian Oscillation(MJO), an intermediate type atmosphere-ocean coupled model is developed and their results are examined. The atmosphere model is a time-dependent non-linear perturbation moist model which can determine the internal heating for itself. The counterpart of the atmosphere model is GCM-type tropical ocean model which has fine horizontal and vertical grid resolutions. In the coupled experiment, warm SST anomaly and increased precipitation and eastward wind and current anomalies associated with ENSO and MJO are properly simulated in Pacific and Indian Oceans. In spite of some discrepancies in simulation MJO, the observed atmospheric and oceanic low-frequency characteristics in the tropics are successfully identified. Among them, positive SST anomalies centered at the 100m-depth of tropical eastern-central Pacific due to the eastward advection of warm water and reduced equatorial upwelling, and negative anomalies in the Indian and western Pacific seem to be the fundamental features of tropical low-frequency oscillations.