• Journal of the Korean Wood Science and Technology
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• v.38 no.5
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• pp.385-390
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• 2010

This study was carried out to manufacture very thin natural elm veneer overlaid charcoal board for enhancing aesthetic value of charcoal board for the indoor application, and to use the advantageous properties of the charcoal as a building material for solving the sick house problem. The thin elm veneer had 26.9% opening ratio. The experiment results showed that the spreading area and the nonvolatile content of adhesive did not affect the gas adsoprtion of fancy veneer overlaid charcoal board. The natural thin elm veneer overlaid charcoal board enhanced not only the aesthetic beauty but also showed the same gas adsorption by the charcoal board.

• Particle and aerosol research
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• v.18 no.3
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• pp.79-86
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• 2022

Many commercial air purifiers currently have deployed granular activated carbon (GAC) filters for removing volatile organic compounds in the indoor air. GACs are generally used to remove gaseous contaminants in the air through adsorption by the inner surfaces of pores. In addition, airborne particles can be also filtered by the surface adsorption of the GACs, which can improve the life-time of the particulate filters. In this study, the filtration efficiency of GACs to ultrafine particles through surface adsorption was investigated at different volume flow rates by deploying a continuous particle filtration system. The polydisperse sodium chloride (NaCl) particles were generated by a set of an atomizer and a diffusion dryer, and then mixed with particle-free air at different volume flow rates. The penetration of ultrafine particles and pressure drop for each experimental condition were measured to figure out the effect of the volume flow rate on the surface adsoprtion of the GACs to particles, ~ 2 mm. The particle filtration efficiency of the GACs decreased as the volume flow rate increased from 4 to 14 lpm. However, the 5 times thicker GAC filter layer decreased the penetration of ultraparticles than a preious study. The filtration efficiency of the single granule was also higher than the previous result in the literature with smaller granule filter materials.

• Journal of the Korean Ceramic Society
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• v.37 no.6
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• pp.517-523
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• 2000

Effect of catalysts, which was catalyzed by acid(HCl and HNO3) and base(NH4OH), on characteristics of the mullite powders prepared by sol-gel methdo wa sinvestigated by XRD, TGA, SEm AND BET. As a result, weight loss as a function of catalysts was in order of HCl=32.6%>HNO3=25.44%>Non=24.0%>NH4OH=22.5%. The mullite powder dried at 100$^{\circ}C$ appeared spherical shape in acid catalyst and different shape in base catalyst, but sintering powder at 1400$^{\circ}C$ appeared very fine particle of 0.05∼0.1$\mu\textrm{m}$ regardless of catalysts. In all cae, the pore quantity, which was capable to adsoprtion, was decreased with increasing temperature. In base catalyst, no change of special surface area in mullite appeared.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.6
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• pp.917-922
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• 2011

Adsorption characteristics of boron on activated carbon was investigated in order to evaluate the use of activated carbon for the removal of boron in desalination processes using SWRO. Boron was removed ranging from 54~60% when the concentration of activated carbon was 1,000 mg/L in 6 hours under the initial boron concentration of 5 mg/L. The removal of boron increased by 20~22% with the increase of pH from 5 to 9. Organic matter had adverse effect on the adsorption of boron on activated carbon. Boron removal decreased by 10-12% when EDTA was added at 1 mg/L under 5 mg/L of boron and 200mg/L of activated carbon. In this results, activated carbon would be a good candidate for a pretreatment of desalination processes by SWRO from the view of mitigating the feed boron concentration to RO and meeting the effluent boron concentration without post-treatment after RO.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.407-416
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• 2009

The objective of this study was to evaluate the variation of physical properties and adsorption capacity after regeneration of Granular Activated Carbon (GAC). It was found that the loss rate of regenerated carbon was related to the usage time of GAC. The correlations between iodide number and loss rate also determined. Effective size and uniformity coefficient for regenerated GAC were within a similar range compared to virgin GAC. This result indicated that the function as media is recovered. Although iodide number and specific surface area for regenerated GAC were not completely recovered compared to that of virgin GAC, cumulative pore volumes of regenerated GAC were increased. Removal efficiency of organic matter in regenerated GAC was resulted the same or slightly higher than that of virgin GAC. This result indicates that the number of mesopore responsible for removal of organic matter was increased after regeneration.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3797-3803
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• 2016

Cervical cancer is the second most common malignancy in women worldwide and thus one of the leading causes of mortality in women. Lovastatin, a non polar, anticholesterol drug has previously been reported to exert antitumour activity in vitro. In the present study, lovastatin from Aspergillus terreus (KM017963) was purified by adsoprtion chromatography and evaluated for its anticancer and anti-oxidant properties with a human cervical cancer cell line (HeLa). Growth inhibitory and proapoptotic effects of purified lovastatin on HeLa cells were investigated by determining its influence on cell numbers, mitochondrial membrane potential (MMP), DNA fragmentation and antioxidant properties in terms of hydroxy radical scavenging effects as well as levels of total reduced glutathione. Cell cycle analysis by flow cytometry (propidium iodide staining) confirmed induction of apoptotic cell death and revealed cell cycle arrest in the G0/G1 phase. Results of the study give leads for the anticancer effects of lovastatin and its potential usefulness in the chemotherapy of cervical cancer.

• Journal of Environmental Science International
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• v.21 no.6
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• pp.705-711
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• 2012

Adsorption experiment of carbon dioxide was performed on MCM41 silica with a 30 wt.% EDA(ethylenediamine) loading at different $CO_2$ inlet concentration and various adsorption temperature. The surface characteristics of $CO_2$ capturing agent were carried out using BET analysis, X-ray diffraction and FT-IR. The results of BET showed 781 $m^2/g$ for MCM41 and 464 $m^2/g$ for EDA/MCM41. X-ray diffraction results reveled typical hexagonal pore system. The higher sorption capacity of EDA/MCM41 was about 80 $mg_{CO2}/g_{sorbent}$ with 50% $CO_2$ inlet concentration and 303 K adsorption temperature. The isosteric heat of adsorption in 303-353 K ranged from -25.47 to -28.24 KJ/mole for EDA/MCM41, which indicates $CO_2$-EDA/MCM41 interaction with exothermic adsorption process. Finally, the performance of EDA/MCM41 in 10 consecutive sorption-desorption runs was a stable with only a minor drop in its sorption capacity.

• Journal of the Korean Ceramic Society
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• v.32 no.8
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• pp.901-908
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• 1995

In aqueous slurry processing of silicon nitride, the interaction of dispersant and binder used as polymeric processing additives on the silicon nitride particle surface was studied to identify the effect of these processing polymeric additives on the ceramic powder processing. The adsoprtion isotherm study of anionic organic molecule as dispersant and nonionic organic molecules as binder of silicon nitricde was studied to investigate the effect of these processing organic additives on the physicochemical properties of silicon nitride particles. As anionic molecule adsorbed onto silicon nitrice surface, the IEP of silicon nitride shifted toward acidic pH and changed the stability of silicon nitride particle. However, the adsorption of binder as nonionic organic molecule onto silicon nitride surface did not changed the IEP but caused the decrease of electrostatic potentials of silicon nitride. These distinctive adsorption behaviors of organic additives on silicon nitride particles can be closely correlated to the stability of silicon nitride particles suspended in aqueous media.

• Clean Technology
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• v.19 no.1
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• pp.65-72
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• 2013

In this study, we investigated the activity of Pd and Cu co-incorporated on mesoporous silica support such as MCM-41 and SBA-15 for catalytic nitrate reduction in water. In pure hydrogen flow, nitrate concentration was gradually decreased with the reaction time, but nitrogen selectivity was too low due to very high pH of reaction medium after the reaction. In order to acquire high nitrogen selectivity, we utilized carbon dioxide as a pH buffer, which resulted in higher nitrogen selectivity (about 40%). For the above reaction conditions, Pd-Cu/MCM-41 showed better performance than Pd-Cu/SBA-15. The physicochemical properties of both catalysts were investigated to figure out the relationship between the characteristics of the catalysts and the catalytic activity on the catalytic nitrate reduction by $N_2$ adsoprtion-desorption, X-ray diffraction (XRD), $H_2$-temperature programmed reduction, X-ray photoelectron spectroscopy (XPS) techniques.

• Clean Technology
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• v.20 no.1
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• pp.28-34
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• 2014

In this study, we synthesized $TiO_2$ supports with nanosized crystalline structure by solvothermal method and prepared $TiO_2$ supported Pd-Cu catalysts. It was shown that the crystalline size of $TiO_2$ support in the catalyst influenced on the catalytic activity of nitrate reduction in water. The catalyst with the smaller crystalline size of $TiO_2$ support presented faster nitrate reduction rate, but had low nitrogen selectivity due to high pH environment of reaction medium during the reaction. Through injection of carbon dioxide as a pH buffer, the nitrogen selectivity increased by about 60%. Furthermore, we investigated that the relationships between the catalytic performance and the physicochemical properties of the prepared catalysts characterized by $N_2$ adsoprtion-desorption, X-ray diffraction (XRD), $H_2$-temperature programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS).