• Journal of Korean Society of Environmental Engineers
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• v.37 no.4
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• pp.210-217
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• 2015

Fluoride removal by acid and heat treated red mud were studied in batch and column system regarding contact time, initial concentration, pH, adsorbent dose, and filter depth. The results showed that acid treated with 0.8 M HCl, had highest adsorption capacity of fluoride and adsorption capacity decreased as heat treatment temperature increased. Sorption equilibrium reached in 30 min at a initial concentration of 50 mg-F/L but 1 h was required to reach the sorption equilibrium at the initial concentration of 500 mg-F/L by 0.8 M acid treated red mud (0.8 M-ATRM). Equilibrium adsorption data were fitted well to Langmuir isotherm model with maximum fluoride adsorption capacity of 23.162 mg/g. The fluoride adsorption decreased as pH increased due to the fluoride competition for favorable adsorption site with $OH^-$ at higher pH. Removal percentage was increased but the amount of adsorption per unit mass decreased by adding the amount of 0.8 M-ATRM. It was concluded that the 0.8 M-ATRM could be used as a potential adsorbent for the fluoride removal from aqueous solutions because of its high fluoride adsorption capacity and low cost.

• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.25-33
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• 1997

To investigate the effects of cow manure compost(CMC) on soil and water environment as non-point source, the elution patterns of anions were determined in muti-layered soil columns which were consisted of one top and one bottom in combination. The top soil columns were uniformly packed with Ap horizon soils amended with air-dried CMC at different ratios(0, 2, 4, 6%, wt/wt), the bottom ones were packed with of B horizon soils of 15, 30, and 45cm in length. After saturating the each soil column, the leachate were collected from the bottom of the column while the double-ionized water was applied from the surface of the column by constant head method. From the hydraulic conductivity and anion eluted were measured in the leachate. Each saturated hydraulic conductivities for top and the bottom soils were 3$\times$$10^{-4}$sec and 1.6$\times$$10^{-3}$cm/sec. Most of water soluble chloride and sulfate, having non-specific adsorption characteristics onto the soil particles, were eluted within 1 PV, showing that there was no apparent retardation of anion movement with increasing CMC contents in the top soils. The effect of soil depths on anion movement were similar to the results of CMC contents. Sulfate of having both of non-specific and specific adsorption characteristics was also recovered in the effluent within 1 PV, while the elution curves were slightly skewed to the right showing that the CMC affected the movement of sulfate. Phosphate of specific adsorption characteristics was hardly eluted within 5 PV.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.5
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• pp.727-736
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• 2006

Granular activated carbon (GAC) has been identified as a best available technology (BAT) by the United States Environmental Protection Agency (USEPA) for removal disinfection by-product (DBP) precursors, such as dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). Rapid small-scale column test (RSSCT) were used to investigate four types of carbon (F400, Norit1240, Norit40S, and Aquasorb1500) for their affinity to absorb natural organic matter (NOM). DOC, $UV_{254}$, and Total dissolved nitrogen (TON) concentrations were measured in the column effluent to track GAC breakthrough. DOC and $UV_{254}$ breakthrough occurred at around 3500 bed volumes (BVs) of operation for all GACs investigated. The $UV_{254}$ breakthrough curves showed 33% to 48% at 8000 BVs, when the DOC was 48% to 65%. All GACs showed greater removal in DOC than $UV_{254}$. The NORIT1240 GAC was determined to have the highest adsorption capacity for DOC and $UV_{254}$. The removal of nitrate (NOTN) had not broken through over BVs. The initial TON breakthrough curves were started around 50%, when the DOC breakthrough was only 10 % at 500 BVs. The curves were gradually increased after 3500 BVs and approximately 69% through 81% of TON breakthrough occurred at 8000 BVs. All of the GACs were able to remove TON, in the case of this investigation the majority of the TON was present as DON. Because nitrate nitrogen was seldom removed and ammonium nitrogen ($NH_3-N$) was not detected in the effluent from RSSCTs even though raw water. The carbon usage rate of DOC was from 2 to 6 times less than that of TON. The NORIT1240 GAC demonstrated the best performance in terms of DOC removal, while the F400 GAC was best in terms of TON removal. Excitation emission matrix(EEM) analysis was used to show that GAC adsorption successfully removed most of Humic-like DOC and Fulvic-like DOCs. However, soluble microbial product(SMP)-like DOC in the absence of raw water were detected in the NORIT40S and Aquasorb1500 GAC. The authors assumed that this results is due probably to the part of GAC in the RSSCT which was converted into biological activated carbon(BAC). To compare with organics removal by GAC according to preloading, the virgin GACs had readily accessible sites that were adsorbed DOC more rapidly than preloaded GACs, but the TDN removal had not showed differences between those GACs.

• Journal of Korean Society of Water and Wastewater
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• v.9 no.3
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• pp.116-126
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• 1995

The purpose of this study was to investigate the removal of ammonium nitrogen by biological nitrification in raw water containing LAS using BAC. At batch teats, LAS removal by ozone followed the first order reaction, and the rate constants(k) by ozone dose 1, 3mg/min.L were $0.040min^{-1}$, $0.062min^{-1}$ respectively. Therefore, the more ozone was dosed, the higher LAS was removed The reaction between ozone and ammonium nitrogen also followed the first order, and rate constants(k) at pH7,8 and 9 were $8.9{\times}10^{-4}min-1$, $3.8{\times}10^{-3}min^{-1}$, and $2.9{\times}10^{-2}min^{-1}$ respectively at ozone dose of 3mg/min.L . Therefore, ammonium nitrogen was little removed by ozone under neutral pH of 7. The continuous flow apparatus had four sets composed of a ozone contacter and a GAC column. Through continuous filtration test for 50days, the following conclusions were derived; (1) LAS was removed 23%, 30% respectively by ozone dose 1, 3mg/L, and was not detected in all column effluents during the period of experiment. Therefore, it appeared that adsorption capacities of each column still remained. (2) Ammonium nitrogen concentration after ozone contact varied little in raw Water because pH of raw water was from 6 to 7, and was transfered to nitrite and nitrate within GAC columns as the result of staged nitrification. After 30days, nitrite was not detected in all column effluents due to biological equilbrium between nitro semonas and nitrobacter Average removals of ammonium nitrogen in each column after the lapse of 30days were the following; ${\cdot}$ column A (ozone dose 3mg/L, EBCT 9.5min): about 100% ${\cdot}$ column B (ozone dose 1mg/L, EBCT 9.5min): 91% ${\cdot}$ column C (ozone dose 3mg/L, EBCT 14.2min): about 100% ${\cdot}$ column D (ozone dose 0mg/L, EBCT 9.5min): 53% Though column A and C reached nitrification of about 100%, column C (longer EBCT than column A) was more stable than column A. (3) After backwash, nitrification reached steady state within 5 to 8 hours. Therefore, nitrification was not greatly affected by backwash. (4) According to the nitrification capacity in depth of column A, C, where 100% nitrification occured. LAS was removed within 20cm, while ammonium nitrogen required more depth to be removed by nitrification.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.284-288
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• 1998

This study was carried out to establish a new efficient method for isolation and purification of ginsenosides. Silica gel column chromatography, having been used for the isolation of ginsenosides, is advantageous to obtain a large amount of ginsenosides. However, it has a disadvantage to isolate ginsenosides to their highest purity. In addition, normal-or reverse-phase HPLC method thus far reported is confined to quantitative analysis. Especially, it has not been possible to isolate racemic 20(S)- and 20(R)-ginsenoside Rg2. In this experiment, isolation and purification of ginsenosides were accomplished by Diaion HP-20 adsorption chromatography, silica gel column chromatography, recrystalization and Prep. HPLC with or without Prep. TLC. From this study, we could establish a new efficient method for isolation and purification of 9 major and/or minor ginsenosides.

• Fibers and Polymers
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• v.2 no.1
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• pp.135-139
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• 2001

Poly(hydroxamic acid) resin beads were prepared and complexed with various metal ions. We used IR spectroscopy to investigate the structure of metal complex. It proved that the products formed by introduction of metal ions gave stable and colored complex. It was found that the resin bead as synthesized would be a good column packing material for continuous extraction. Energy dispersive spectroscopy was use to study the distribution of metal ions in the resin matrix. It could be tentatively concluded that adsorption and diffusion of metal ions in the chelating resins mainly depended on the loading of the resin matrix which indicated interacting sites with metal ions.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.7
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• pp.1081-1087
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• 2000

Gromwell colorants were extracted with methanol and dried. Four fractions were obtained by silica gel adsorption column chromatography using step-wise elution method. Relative ratio of four fraction is 1.00:0.07:0.22:0.30(Fl:F2:F3:F4) and gromwell colorants mainly consist of Fl, F3 and F4. IR analysis shows that each fraction has similar structure. Main component of gromwell extracts is acetyl derivative of naphthoquinone, and the rest are isobutyl derivative and isovaleryl derivative etc., in order. Gromwell colorants exhibit relatively good affinity to protein and polyamide fibers, but low affinity to cellulose and regenerated cellulose fibers.

• The Korean Journal of Nuclear Medicine
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• v.7 no.1
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• pp.51-54
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• 1973

The use of ion-exchange resins for the treatment of radioactive wastes has many advantages, but thes eare rather expensive as compared with the Korean vermiculite. The Korean vermiculite has slightly different chemical constituents from the ones produced in other countries, and its physical properties might be applicable to the management of radioactive waste, in a small nuclear installation. The decontaminating effect of Korean vermiculite for the low-level radioactive liquid was investigated. $^{106}Ru,\;^{90}Sr,\;and\;^{137}Cs$ were utilized for the experiments. The removal rates by Korean vermiculite were calculated for $^{106}Ru,\;^{90}Sr\;and\;^{137}Cs$ and the removal rates increased as the weight of vermiculite in the exchange column increased. The decontaminating constants, $K_d$ of the Korean vermiculite for $^{106}Ru,\;^{90}Sr\;and\;^{137}Cs$ were 2.7, 69.3 and 263ml/g respectively. Through the results of experiments, the application of Korean vermiculite column to the treatment of low-level radioactive waste is quite feasible.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.485-491
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• 1995

Protein ion exchange chromatography was studied experimentally in order to prove the theoretical prediction from the linear model of Yamamoto, S. et al (1). Adsorption isotherms were measured as a function of ionic strength in a batch experiment. The relationship between the characteristics of chromatogram and the operating conditions of ionic strength, flow rate, length of column, concentration and amount of protein sample were studied. At the higher ionic strength, the lower flow rate and the longer column conditions, the higher number of plate was obtained. Satisfactory agreement was observed between the experimental and the calculated chromatograms except for the case of high protein concentration.

• KSBB Journal
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• v.8 no.3
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• pp.287-294
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• 1993

For the purpose of combining the purification processes for several biologically active proteins form human urine, an efficient integrated fractionation procedure has been investigated. The procedure was started by concentration with ultrafiltration and pH precipitation followed by a selectable combination of chromatography on gel filtration, adsorption, ion exchanger, affinity, and reverse phase column. By this process, the purified urokinase, epidermal growth factor and albumin migrated as a single band on SDS-polyacrylamide gel electrophoresis and were fully active. The recoveries of these purified proteins were 48%, 17%, and 46%, respectively.