• 한국가구학회지
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• 제17권3호
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• pp.87-94
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• 2006

The purpose of this study was to evaluate the relationships between the mixing ratio and water vapor sorption property of charcoal-based loess composites for furniture & building materials with environmental friendly. Charcoal-based loess composite can be easily made by blending method with water. But the composites had much brittle fracture pattern with the increase of charcoal content. That is due to the lack of loess that takes linkage role of composites. In water vapor sorption properties, adsorption ability of charcoal was about six times higher than that of loess. Therefore, vapor sorption ability was maximum at the mixture ratio of charcoal 80% and loess 20%. It is considered that wood charcoal based inorganic composite materials can be used for various purposes as a building interior & exterior and furniture members.

• Journal of the Korean Wood Science and Technology
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• 제10권4호
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• pp.38-52
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• 1982

The effect of propylene oxide, butylene oxide, furan resin, and vinylpyrrolidinone in controlling wood dimensional stability have been examined. Wood in the green or ovendry condition was treated with various chemical treatments using a vacuum-pressure procedure, and treated specimens were tested for tangential sweelling, moisture gain, and changes in sorption hysteresis. Results' indicate that propylene oxide, and butylene oxide enhanced with the crosslin king agent trimethylol propane trimethacrylate and applied to ovendry wood were the most efficient chemical treatments in controlling tangential sweeling caused by liquid water or water vapor, and in reducing water vapor adsorption. The sorption behavior of treated wood as depicted by the ratios of sorption was "very favorable" in most instances. In the particular case of furan resin treatments, ratios of sorption were improved from 25 to 100 percent as compared to those of untreated wood.

• 한국물환경학회지
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• 제32권3호
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• pp.303-309
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• 2016

This study aimed to assay the biological removal of TDS (total dissolved solids) from RO (reverse osmosis) rejected water. Following bio-sorption of TDS with AGS (aerobic granular sludge), the effects of TDS on biological nitrogen removal were examined. The bio-sorption of TDS after AGS treatment was confirmed by checking for TDS removal efficiency and surface analysis of microorganisms with SEM and EDS. Then, the effects of TDS on biological nitrogen removal and the denitrification efficiency were evaluated using the MBR reactor. According to the results, the bio-sorption of TDS with AGS was 0.1 mg TDS/mg AGS, and we confirmed that the microorganism surfaces had adsorbed the TDS. Biological nitrogen removal efficiency was measured at inhibiting denitrification at 4,000 mg/L of TDS-injected material. Based on this study, it is necessary to pretreat TDS-containing RO rejected water and to maintain TDS concentration lower than a specific value (≤4,000 mg/L), when considering biological nitrogen removal.

• Macromolecular Research
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• 제12권1호
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• pp.26-31
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• 2004

Using gravimetry, we have studied the diffusion of water into sulfonated polystyrene ionomers. Diffusion coefficients were calculated from Fick's equation. The water sorption was found to be dependent on the ion content (3.6-11 mol％) and the nature of the cation (H, Na, Li, or Zn). The sorption kinetics indicates a slight deviation from Fickian behavior. We used the analytical solution of Fick's equation to evaluate the concentration profiles, which are in good agreement with the experimental results.

• The Journal of Advanced Prosthodontics
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• 제7권4호
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• pp.278-287
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• 2015

PURPOSE. The aim of this study was to compare the color stability, water sorption and cytotoxicity of thermoplastic acrylic resin for the non-metal clasp dentures to those of thermoplastic polyamide and conventional heat-polymerized denture base resins. MATERIALS AND METHODS. Three types of denture base resin, which are conventional heat-polymerized acrylic resin (Paladent 20), thermoplastic polyamide resin (Bio Tone), thermoplastic acrylic resin (Acrytone) were used as materials for this study. One hundred five specimens were fabricated. For the color stability test, specimens were immersed in the coffee and green tee for 1 and 8 weeks. Color change was measured by spectrometer. Water sorption was tested after 1 and 8 weeks immersion in the water. For the test of cytotoxicity, cell viability assay was measured and cell attachment was analyzed by FE-SEM. RESULTS. All types of denture base resin showed color changes after 1 and 8 weeks immersion. However, there was no significant difference between denture base resins. All specimens showed significant color changes in the coffee than green tee. In water sorption test, thermoplastic acrylic resin showed lower values than conventional heat-polymerized acrylic resin and thermoplastic polyamide resin. Three types of denture base showed low cytotoxicity in cell viability assay. Thermoplastic acrylic resin showed the similar cell attachment but more stable attachment than conventional heat-polymerized acrylic resin. CONCLUSION. Thermoplastic acrylic resin for the non-metal clasp denture showed acceptable color stability, water sorption and cytotoxicity. To verify the long stability in the mouth, additional in vitro studies are needed.

• 한국환경과학회지
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• 제15권11호
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• pp.1053-1059
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• 2006

This study was performed to investigate the possible uses of waste sludge for the removal of heavy metal ions. The adsorption experiments were conducted with wastes such as sewage treatment sludge, water treatment sludge and oyster shell to evaluate their sorption characteristics. Heavy metals selected were cadmium, copper and lead. in the sorption experiments on the sewage treatment sludge, water treatment sludge, oyster shell and soil, sorption occurred in the beginning and it reached equilibrium after 40 minutes on the oyster shell and 4 hour on the sewage treatment sludge and water treatment sludge. Results of Freundlich isotherms indicated that sewage treatment sludge could be properly used as an adsorbent for heavy metals and sorption strength of heavy metals was in the order of Pb > Cu > Cd. In the influence of pH on the adsorbents, sorption rate was more than 80% in pH 4 and most of heavy metals were adsorbed in pH 9. Adsorption rate of Cd decreased with decreasing pH and then adsorption rate of Cu was lower in soil.

• 멤브레인
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• 제6권4호
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• pp.227-235
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• 1996

PVA의 수산화기와 PAA의 카르복실산기 사이의 반응에 의해 가교구조를 갖는 PAA-PVA 막을 제조하였으며 팽윤실험을 통해 순수물, 순수초산 그리고 이들의 혼합물하에서의 가교막들의 팽윤거동을 각각 살펴보았다. 90wt% 초산 수용액하에서의 팽윤실험에서 막에 PAA함량이 높을때 물의 팽윤거동이 초산보다 더 촉진됨이 관찰되었는데 이는 팽윤과정에서의 각 구성 성분간의 짝짓기(coupling) 결과로 사료되며 또한 막의 팽윤비와 가교밀도는 경쟁적으로 투과물의 투과거동에 서로 상반되게 영향을 끼침이 관찰이 되었다. 온도에 따른 투과속도의 Arrhenius 관계에서 구한 투과활성화에너지를 통해 투과성분의 투과거동을 분석하였다.

• Membrane and Water Treatment
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• 제14권1호
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• pp.19-25
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• 2023

The studies on the effect of different plastic properties (e.g., types, shapes, presence of additivies) on the sorption of contaminants in the agricultural environment are limited. In this study, Cu and Pb, the commonly found heavy metals in the environment, were used to investigate the sorption capacities of microplastics (MPs). The Pb sorption capacity increased in the order of polystyrene (PS)<polyethylene (PE)<polyvinyl chloride (PVC). The estimated Cu sorption capacity was greater for the PE films than the PE fragments, while the sorption strength was greater for the PE fragments. This suggests that the shapes of MPs can affect the contaminant sorption capacities. With the PE fragments, the Pb sorption capacity was greater than the Cu sorption capacity by 10-12 times. Also, the Pb and Cu sorption capacities were greater for the PE fragments with additives than the PE fragment without additives. After the sorption of Pb or Cu on MPs, the toxic effects of the Pb or Cu solutions were decreased, suggesting that the toxic effects of contaminants can be affected by the co-presence of MPs in the environment. Overall, the results show that different types and shapes of MPs and the presence of additives can affect the heavy metal sorption capacities of MPs.

• 한국지하수토양환경학회지:지하수토양환경
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• 제27권6호
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• pp.11-21
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• 2022

Sorption of phenanthrene (PHE) and pyrene (PYR) in several sorbents, i.e., natural soil, BionSoil^®, Pahokee peat, vermicompost and Devonian Ohio Shale and a surfactant (hexadecyltrimethyl ammonium chloride)-modified montmorillonite (HDTMA-M) were investigated. Pyrene exhibited higher sorption tendency than phenanthrene, as predicted by its higher octanol to water partition coefficient (K_ow). Several sorption models: linear, Freundlich, solubility-normalized Freundlich model, and Polanyi-Manes model (PMM) were used to analyze sorption isotherms. Linear isotherms were observed for natural soil, BionSoil^®, Pahokee peat, vermicompost, while nonlinear Freundlich isotherms fitted for Ohio shale and HDTMA-M. The relationship between sorption model parameters, organic carbon content (f_oc), and elemental C/N ratio was studied. In the binary competitive sorption of phenanthrene and pyrene in natural soil, competition between the solutes caused reduction in the sorption of each solute compared with that in the single-solute system. The ideal adsorbed solution theory (IAST) coupled with the single-solute Freundlich model was not successful in describing the binary competitive sorption equilibria. This was due to the inherent nature of linear sorption of phenanthrene and pyrene in natural soil. The result indicates that the applicability of IAST for the prediction of binary competitive sorption is limited when the sorption isotherms are inherently linear.

• Nuclear Engineering and Technology
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• 제32권4호
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• pp.342-349
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• 2000

A soil whose texture is silt loam was collected for the study from an area around a nuclear facility in Korea. The equilibrium sorption coefficient between Co$^{2+}$in water and the soil was 1.51/kg, on the other hand, that between Co$^{2+}$ in EDTA and the soil was 0.21/kg. The values calculated by the developed nonequilibrium sorption code corresponded to the experimental values better than those calculated by the existing equilibrium sorption code. When an EDTA solution was used as a solvent to decontaminate Co$^{2+}$ in the soil column, the relative Co$^{2+}$ concentrations of the effluent were higher at 2~10 pore volumes than those of the case using water. The soil in the column was decontaminated by 95.5% of the total amount of Co$^{2+}$ after being flushed with EDTA solution of 20 pore volumes.e volumes.