• Applied Biological Chemistry
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• v.36 no.2
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• pp.99-104
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• 1993

In order to explore the brassinosteroid-active component in Cassia tora, methanol extract of immature seeds was purified by sequences of solvent fractionation, silica gel adsorption chromatography, Sephadex LH-20 chromatography, charcoal adsorption chromatography and Bondesil chromatography. The activity of brassinosteroid was monitored by the rice inclination test and its presence could be confirmed in each purification step. The purified active components were separated by silica gel adsorption chromatography. Brassinosteroid substances in separated active fractions were identified as teasterone, castasterone, brassinolide by TLC and HPLC. Our work is probably the first report of endogenous brassinosteroid in Cassia tora. The content of brassinosteroid in Cassia tora as converted into brassinolide was $3.5{\sim}5.5\;ng/g$ fresh weight. The order of brassinosteroid contents was toward to be teasterone, castasterone, brassinolide.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.360-365
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• 1996

To investigate the presence of brassinosteroids in rice bran and pㅐlished rice, they were extracted with MeOH. The extracts were purified through sequential procedure of solvent fractionation, silica gel adsorption chromatography, Sephadex LH-20 column chromatography and charcoal adsorption chromatography. The activity of brassinosteroids was monitored by the rice inclination test and its presence was confirmed in each purification step. The purified active components were further separated by TLC and HPLC. Brassinosteroids in active fractions of rice bran were identified as castasterone and teasterone by HPLC. We acknowledge that our work is probably the first report of brassinosteroids in mature seeds of rice The more amount of brassinosteroids was confirmed in rice bran than polished rice. The contents of castasterone and teasterone which were identified in rice bran were 0.15 ng/g and 0.37 ng/g, respectively.

• Journal of environmental and Sanitary engineering
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• v.16 no.2
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• pp.91-99
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• 2001

Cross linked chitosan beads showed high selective adsorption abilities in order of $Au^{3+}$ > $Hg^{2+}$ > $Cu^{2+}$ > $Cd^{2+}$ > $Pt^{4+}$ > ${UO_2}^{2+}$ ions in mixed solution of various metal ions at pH 4.5. N-methyltyiobenzylated chitosan beads(MTB-chitosan beads) were prepared treating with p-(methylthio) benzaldehyde after cross linking of chitosan beads to give them a high selectivity in adsorption of metal ions. The MTB-chitosan beads demonstrated their selectivity on precious metals among various metal ions distinctively. Particularly, the MTB-chitosan had a peculiar selective adsorption on $Pd^{2+}$, $Au^{2+}$, and $Hg^{2+}$ions whilst the cross linked chitosan beads showed its high adsorption on $Pd^{2+}$ at pH 1.1. On the other hand, the cross linked chitosan beads showed its superiority in selective adsorption on $Au^{2+}$, $Cu^{2+}$, and $Hg^{2+}$ions to the MTB-chitosan at pH 4.5 of the test solution. Thus metal selectivities were given to chitosan beads through chemical modifications.

• Journal of Korea Soil Environment Society
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• v.5 no.3
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• pp.17-23
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• 2001

The adsorption and movement characteristics of herbicide pendimethalin was studied in three kinds of soil, sandy loam, silty clay and loam. The results of the batch test and columnexperimentweresummarizedasfollows. The shaking time reached to the adsorption equilibrium of pendimethalin in soils was 6 hours. The adsorption rates of pendimethalin for sandy loam, silty clay and loam were 59.6%, 77.3% and 64.0%, respectively. The adsorption isotherms with the Freundlich equation showed better consistency than that with the Langmuir one. The adsorption coefficients of pendimethalin for soils were 8.0. 16.1 and 9.5. respectively. When breakthrough point was 0.05Co, the breakthrough times reached for soils were 256 minutes, 810 minutes and 420 minutes. respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.1
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• pp.68-76
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• 2014

The present study has evaluated the $CO_2$ adsorption amount of activated carbon pellets (AC). Coconut shell based test AC were modified with surface impregnation of glycine, glycine metal salts and monoethanolamine for low level $CO_2$ (3000 ppm) adsorption. Physical and chemical properties of prepared adsorbents were analyzed and the adsorbed amount of $CO_2$ was investigated by using pure and 3,000 ppm $CO_2$ levels. The impregnation of nitrogen functionalities was verified by XPS analysis. The adsorption capacity for pure $CO_2$ gas was found to reach upto 3.08 mmol/g by AC-LiG (Activated carbon-Lithium glycinate), which has the largest specific surface area ($1026.9m^2/g$). As for low level $CO_2$ flow the primary amine impregnated adsorbent showed 0.26 mmol/g of adsorption amount, indicating the highest selectivity. An adsorbent with potassium-glycine salts (AC-KG, Activated carbon-Potassium glycinate) instead of amine presented with 0.12 mmol/g of adsorption capacity, which was higher than that of raw activated carbon granules (0.016 mmol/g).

• Journal of Korean Society of Water and Wastewater
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• v.29 no.6
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• pp.609-615
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• 2015

This study was carried out for characterization of MIO synthesized in our laboratory by co-precipitation method and applied isotherm and kinetic models for adsorption properties. XRD analysis were conducted to find crystal structure of synthesized MIO. Further SEM and XPS analysis was performed before and after phosphate adsorption, and BET analysis for surface characterization. Phosphate stock solution was prepared by KH2PO4 for characterization of phosphate adsorption, and batch experiment was conducted using 50 ml conical tube. Langmuir and Freundlich models were applied based on adsorption equilibrium test of MIO by initial phosphate solution. Pseudo first order and pseudo second order models were applied for interpretation of kinetic model by temperature. Surface area and pore size of MIO were found $89.6m^2/g$ and 16 nm respectively. And, the determination coefficient ($R^2$) value of Langmuir model was 0.9779, which was comparatively higher than that of Freundlich isotherm model 0.9340.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.316-324
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• 2009

Carbon based sorbents for $CO_2$ adsorption were prepared by impregnation with alkali metals ($Li^+$, $K^+$) and alkaline earth metals ($Ca^{2+}$, $Mg^{2+}$). BET surface area of test sorbents was lower than the intrinsic activated carbon. In particular, impregnation of $Ca^{2+}$ or $Mg^{2+}$ resulted in lower surface area of specific adsorption sites than that of $Li^+$ or $K^+$. While the adsorption capacity for $CO_2$ was high in the sorbents containing $Ca^{2+}$ and $Mg^{2+}$, strong interaction with $CO_2$ would cause to drop the capacity after regeneration. The adsorption was found high relatively in the flow with a high concentration of $CO_2$ and in a low flow rate. The adsorption isotherm for the present modified AC sorbents fits well with the Freundlich model.

• Journal of the Korean Applied Science and Technology
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• v.16 no.1
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• pp.59-65
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• 1999

For a cosmetic plant wastewater containing surfactants of high concentration, adsorption treatment by granular activated carbon(GAC) having different pore size distribution was studied. Three sorts GACs were used and regenerated afterwards with methanol. Experiments were composed of batch process and column test for both virgin and regenerated GACs. Following conclusions were drawn from the study: Methylene blue activating substance(MBAS) adsorption data from the batch tests for three GACs are described well by BET isotherm and Freundich isotherm. Simulation with the BET isotherm shows that maximum adsorption appears to be affected not only by specific surface area but also by pore size distribution. Maximum adsorption from the BET isotherm for MBAS appears to diminish as the number of reactivation increases. The diminishing ratio of maximum adsorption appears to decrease as the pore size decreases. Recovery ratio of the methanol by vacuum evaporation from the spent methanol ranges from 95% to 97%.

• Bulletin of the Korean Chemical Society
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• v.22 no.7
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• pp.716-720
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• 2001

To test the metal ion effect, hydrolysis experiments for two cellobiohydrolases (CBHⅠ and CBH Ⅱ) from Trichoderma reesei have been carried out in the presence of 10 mM metal ions, such as Cu++, Mn++, Ca++, Hg++, Ba++, Pb++, and Cd++. The addition of Mn++, Ba++, and Ca++(10 mM) during the hydrolysis of Avicel PH 101 caused an increase in the total reducing sugar (TRS) for CBH Ⅰ by 142, 135, and 114 percent, respectively. Those for CBH Ⅱ increased by 177, 175, and 115 percent, respectively. The Mn++ was the most stimulatory metal ion, whereas Hg++ was the most inhibitory metal ion. The adsorption experiments were performed to investigate how the influence of Mn++ and Hg++ on the hydrolysis is related to the adsorption of cellobiohydrolases on cellulose. The increase in TRS during hydrolysis by adding Mn++ caused an increase in adsorption affinity (Kad) and tightness (ΔHa). While, the decrease of TRS during hydrolysis by adding Hg++ caused a decrease in the adsorption affinity (Kad) and tightness (ΔHa). These results indicate the changes in the tightness and affinity of adsorption by adding metal ions play a crucial role in the degradation of the microcrystalline cellulose.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.03a
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• pp.179-186
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• 1997