• Journal of Korean Society of Water and Wastewater
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• v.24 no.4
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• pp.413-423
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• 2010

Eutrophication caused by the excessive supply of phosphorus to water has been considered as one of the most important environmental problems. In this study, the titanium mesostrcture, which was prepared with the template of different surfactant, was tested to confirm the applicability as an adsorbent for phosphorus removal and evaluate the phosphorus removal efficiency. X-ray diffraction analysis, phosphorus adsorption istotherm and kinetic test were performed for the titanium mesostructure, synthesized at various base material/surfactant molar ratio and with different surfactant templates. From the results, we found that mesostructure was synthesized at the base material/surfactant molar ratio of 1/0.25 was most uniformly and clearly formed and thus the adsorption capacity was also maximized.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.4
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• pp.94-102
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• 1996

This study was accomplished to get the basic data for the optimum chemical feed, evaluating interference between tastes and odors chemicals and coagulants in existing water treatment processes. During the tastes and odors occurs at D intaking tower area in 1995, PAC(Powdered Activated Carbon) feed with coagulants was PAC feed only and with coagulant simultaneously were appeared TON removal efficiency about 84%-87% within 20 min reaction time, but feed with time intervals was about 98% TON removal efficiency. Therefore in the case of PAC feed with coagulant, it is effective to feed coagulant on some time intervals in removing tastes and odors. It is not effective to feed PAC with chlorine dioxide($ClO_2$) or chlorine simultaneously in removing tastes and odors, because these chemicals were reduced the adsorption capacity of PAC.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11b
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• pp.214-221
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• 2005

Spent ion-exchanged resin generated from various purification systems in CANDU reactor is causing concern due to a limited storage capacity and safe disposal. As a suggestion for a proper treatment technology for the spent ion-exchanged resin containing a high activity of C­14 radionuclide which would be classified as Class A and C wastes, a fundamental study for the development of C-14 removal technology from a spent resin was performed. The adsorption characteristics of the inactive $HCO_3^-$ ion and other ions in a stripping solution on IRN-150 mixed resin was evaluated and the removal technology of the $HCO_3^-$ ion adsorbed on IRN-150 by an alkaline stripping method was proposed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.1
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• pp.31-37
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• 2002

This paper was investigated to clarify the possibility of a biodegradation of materials adsorbed on different porous granular-activated carbons (GACs) such as coal-& coconut-based GAC. Total organic carbon, humic substance and ammonia were used to compare their removal efficiencies. The objective of this study is to determine the adsorption capacity of bioregenerated GAC. When raw water reacted with chloride, the yield of THMs increased as a function of the input amount of chloride. The formation of trihalomethanes (THMs) was investigated in water treated with chlorine when humic acid was used as THM precursor. As the input amount of chloride in raw water increased by two or five-fold to remove the $NH_3$, the chloroform of the THMs significantly increased also five or ten-fold. It was found that the chloroform was significantly removed by the treatment of biological activated carbon (BAG) in comparison with the ozone treatment, and the removal efficiency of THMs in coal-typed GAC was $10-30\%$ better than coconut-typed GAC due to the biological degradation on the surface of the activated carbons.

• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1073-1077
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• 2002

Binding of dodecyl trimethylammonium bromide (DTAB) to human and bovine hemoglobin and globin samples has been investigated in 50 mM glycine buffer pH = 10, I = 0.0318 and 300 K by equilibrium dialysis and temperature scanning spectrophotometry techniques and method for calculation of average hydrophobicity. The binding data has been analyzed, in terms of binding capacity concept $({\theta})$, Hill coefficient (nH) and intrinsic Gibbs free energy of binding $({\Delta}Gbv).$ The results of binding data, melting point (Tm) and average hydrophobicity show that human hemoglobin has more structural stability than bovine hemoglobin sample. Moreover the results of binding data analysis represent the systems with two and one sets of binding sites for hemoglobin and globin, respectively. It seems that the destabilization of hemoglobin structure due to removal of heme group, is responsible of such behavior. The results indicating the removal of heme group from hemoglobin caused the depletion of first binding set as an electrostatic site upon interaction with DTAB and exposing the hydrophobic patches for protein.

• Journal of Environmental Science International
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• v.8 no.1
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• pp.69-74
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• 1999

Soil properties which affect the retention of Pb(I) were investigated in the laboratory. It was determined, through selective removal, that organic matter and Fe-oxides are of lesser importance in influencing Pb retention than are soil clay minerals. The following trend : clays ＞ organic matter ＞ Fe-oxides represents the relative importance of each constituent in the adsorption of Pb by soils. The consistently greater Pb uptake by surface over subsurface samples was apparently due to differences in organic matter content, inasmuch as organic matter removal from both resulted in similar adsorption characteristics. All five soils stooled exhibited a pH-dependent trend of adsorption. The extent of Pb adsorption was least at low pH values(4~5), was maximum in the neutral pH range, and leveled off or diminished under more alkaline conditions. There was no strong correlation between Pb uptake and soil cation exchange capacity as routinely measured by the NH$_4$OAc method. A knowledge of clay mineralogy in conjunction with soil pH is suggested as being the most reliable guide to predicting Pb retention by soils.

• Journal of Environmental Science International
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• v.12 no.10
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• pp.1061-1069
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• 2003

The adsorption behaviors of strontium and cesium ions on fly ash, natural zeolites, and zeolites synthesized from fly ash were investigated. The zeolites synthesized from fly ash had greater adsorption capabilities for strontium and cesium ions than the original fly ash and natural zeolites. The maximum adsorption capacity of synthetic zeolite for strontium and cesium ions was 100 and 154 mg/g, respectively, It was found that the Freundlich isotherm model could fit the adsorption isotherm. The distribution coefficients (K$\_$d/) for strontium and cesium ions were also calculated from the adsorption isotherm data, The distribution coefficients decreased with increasing equilibrium concentration of strontium and cesium ions in solution. By studying the removal of cesium and strontium ions in the presence of calcium, magnesium, sodium, potassium, sulfate, nitrate, nitrite, and EDTA (in the range of 0.01 - 5 mM) it was found that these coexistence ions competed for the same adsorption sites with strontium and cesium ions.

• Journal of information and communication convergence engineering
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• v.5 no.3
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• pp.259-264
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• 2007

According to the development and wide use of broad band internet etc., diverse application technologies using large capacity data such as images have been progressed and in these systems, for accurate acquisition and precise applications of an original signal, the degradation phenomenon generated in the transmission process etc. should be removed. Noises have become known as the main cause of the degradation phenomenon and especially Gaussian noise represents characteristics occurring dependently in image signals and degrades detail information such as edge. In this paper, we removed Gaussian noise using a subdivided nonlinear function according to a threshold value and analyzed the histogram acquired from an edge image to establish a threshold value adaptively, and strengthened detail information of image by using the postprocessing. In simulation results, the proposed method represented excellent performance from comparison of MSE with existing methods.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.1-4
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• 2006

Because do placing joint after smallest $1{\sim}3$ day about concrete that is placed beforehand in field, it is difficult that remove laitance happening harden concrete. This laitance happens a problem of bond properties, deterioration in strength. In this research got following conclusion as result that do research about bond properties the way of disposal placing joint. Air Jet is loft interior and exterior. Water Jet appeared that laitance Removal Capacity is superior to dimension within 5%. Deterioration in strength is measured 37% by splitting tensile strength test result by laitance. Deterioration in strength by laitance do more than 30% that removal of laitance is predicted must consist necessarily at concrete horizontality placing joint stroke.

• Advances in environmental research
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• v.5 no.4
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• pp.225-235
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• 2016

Synthesized hydroxyapatite (Hyd) and Fe-hydroxyapatite (Fe-Hyd) composite were used for the removal of Methylene Blue (MB) from aqueous solutions in this study. The effect of adsorbent amount, pH and initial MB concentration were carried out to investigate in the aqueous solution. The kinetic study shows that the MB adsorption process with Hyd or Fe-Hyd follow pseudo-second order kinetic model. Experimental results are well fitted to the Langmuir isotherm model. The maximum adsorption capacities of Hyd and Fe-Hyd were obtained as 2.90 mg/g and 5.64 mg/g for MB according to Langmuir Isotherm models, respectively. Fe-Hyd composite increased the adsorption capacity of Hyd by 1.95 times that Hyd. It is concluded that Fe-Hyd composite is promising and economical adsorbent for MB removal in the aqueous solution.