• Proceedings of the Materials Research Society of Korea Conference
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• 1994.11a
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• pp.2-2
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• 1994

• Journal of Environmental Science International
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• v.5 no.3
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• pp.369-376
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• 1996

The adsorption of the anionic surfactants, sodium lauryl sulfate (SLS) and sodium dodecylbenzene sulfonate (SDBS) anion surfactants form aqueous solutions with nonionic resins, Amberlite XAD-2, XAD-4 and XAD-7 at temperatures in 15~45$^{\circ}C$ range was studied. Several adsorption isotherm models were used to fit the experimental data, The best results were obtained with the Redlich-Peterson equation and the Freundlich model provided remarkably good fits. For a particular resin at a particular temperature, SDBS was more extensively adsorbed than SLS. The highest adsorption were obtained with XAD-4 resin and the specific surface area of the resins plays a major role in adsorption of the surfactants. Estimations of the isosteric heat of adsorption were indicative of an exothermic process, and their magnitudes manifested a physisorption process.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.26-33
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• 1994

Adsorption isotherms of nitrogen and argon on various adsorbents measured up to present by authors are used to make the V-t plots using various numerical and the analytical standard adsorption isotherms to estimate the appropriateness of these standard isotherms. It is confirmed that the analytical FHH equation is appropriate for wide range of adsorbents as a standard isotherm.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.934-938
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• 2011

The curvature dependence of the physisorptions of $H_2$ on graphene surface and their barrier to the chemisorptions has been studied. The graphene with steeper curvature can adsorb $H_2$ stronger due to the more $sp^3$ character of the carbon. However, for the negative curvature, the binding strength of the physisorption and the barrier to the chemisorptions are determined by steric repulsion as well as the $sp^3$ character.

• Bulletin of the Korean Chemical Society
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• v.10 no.3
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• pp.292-297
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• 1989

In this work we have experimentally observed the physisorption isotherms for nitrogen, TMS, cyclohexane, benzene, and n-hexane adsorbed on flat aluminum foil surface and have analyzed them theoretically on the basis of the theory proposed by Chang et al. The results show that the theory by Chang et al. can provide a useful means to describe the physisorption of gases on uniform flat solid surface which is essentially important for analysis of the pore volume distribution in porous solid surface. We have also discussed the application of the results obtained in this work to the analysis of pore volume distribution in porous alumina we reported previously.

• Carbon letters
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• v.25
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• pp.33-42
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• 2018

Activated carbon (AC) was modified by ammonium persulphate or nitric acid, respectively. AC and the modified materials were used as catalyst supports. The oxygen groups were introduced in the supports during the modifications. All the supports were characterized by $N_2$-physisorption, Raman, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and thermogravimetric analysis. Methanol synthesis catalysts were prepared through wet impregnation of copper nitrate and zinc nitrate on the supports followed by thermal decomposition. These catalysts were measured by the means of $N_2$-physisorption, X-ray diffraction, XPS, temperature programmed reduction and TEM tests. The catalytic performances of the prepared catalysts were compared with a commercial catalyst (CZA) in this work. The results showed that the methanol production rate of AC-CZ ($23mmol-CH_3OH/(g-Cu{\cdot}h)$) was higher, on Cu loading basis, than that of CZA ($9mmol-CH_3OH/(g-Cu{\cdot}h)$). We also found that the modification methods produced strong metal-support interactions leading to poor catalytic performance. AC without any modification can prompt the catalytic performance of the resulted catalyst.

• Journal of the Korean Society of Safety
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• v.8 no.1
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• pp.29-34
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• 1993

Two major hazardous gases. SOx and NOx. are emissioned from fossile fuels. SOx has been removed when oil is refined but NOx hasn't. So NOx is very serious problem in air pollution now There are several technologies to remove NOx. e.g. cooling method. scrubbers method. combustion method, polymer membrane method and adsorbent methods. Polymer membrane and adsorbent methods have good economic merit in removal systems of low content hazard gases. Traditional absorbents are porous silicas, aluminas. active carbon and zeolites. But these absorbents act only physisorption which has less removal performance than chemisorption. In this study. polymeric absorbent which has chemisorption as well as physisorption was analyzed about chemical structure and experimented about optimum operation conditions. The results showed that the chemical structure of the polymeric absorbent was expected as polystyrene having -N-CH$_2$COOH absorbent was revealed about 310$m^2$/g. The molar ratio of absored NO to charged NO in absorption experiments was shown 60% of the polymeric absorbent and 45% of zeolite absorbent at 3$0^{\circ}C$.

• Korean Journal of Crystallography
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• v.16 no.2
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• pp.61-65
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• 2005

Despite a short history, the research on porous coordination polymers is gaining importance in inorganic chemistry thanks to facile synthesis, unambiguous characterization by X-ray diffraction and potentials as high-surface-area materials. Recently, gas sorption properties of various porous materials are under active investigations in order to know whether it is possible to store industrially important gases through physisorption, and porous coordination polymers are one of the most promising candidates for such a purpose. This article reviews two recent papers reporting a series of isomorphous frameworks based on Zn(II), dicarboxylate and diamine ligands and their gas sorption properties.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.6
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• pp.493-499
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• 2010

Steam reforming (SR) of glycerol, a main by-product of manufacturing process of bio-diesel, for the production of hydrogen was investigated over the Ni-based catalysts. The Ni-based catalysts were prepared by an impregnation method, and characterized by $N_2$ physisorption, CO chemisorption, XRD and TEM techniques. It was found that the Ni/${\gamma}-Al_2O_3$ catalyst showed higher conversion and catalytic stability for the carbon formation than the other catalysts in the steam reforming of glycerol under the tested conditions. The results suggest that the steam reforming of glycerol over modified Ni/${\gamma}-Al_2O_3$ catalyst minimized carbon formation can be applied in hydrogen station for fuel-cell powered vehicles and fuel processor for stationary and portable fuel cells.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.1031-1035
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• 2007

Prostate specific $antigen-{\alpha}_1-antichymotrypsin$ was detected by a double-enhancement strategy involving the exploitation of both colloidal gold nanoparticles (AuNPs) and precipitation of an insoluble product formed by HRP-biocatalyzed oxidation. The AuNPs were synthesized and conjugated with horse-radish peroxidase-PSA polyclonal antibody by physisorption. Using the protein-colloid for SPR-based detection of the PSPJACT complex showed their enhancement as being consistent with other previous studies with regard to AuNPs enhancement, while the enzyme precipitation using DAB substrate was applied for the first time and greatly amplified the signal. The limit of detection was found at as low as 0.027 ng/ml of the PSA/ACT complex (or 300 fM), which is much higher than that of previous reports. This study indicates another way to enhance SPR measurement, and it is generally applicable to other SPR-based immunoassays.