• Economic and Environmental Geology
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• v.48 no.2
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• pp.131-145
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• 2015

Thermodynamic prediction of weathering products from primary aquifer minerals around underground disposal sites was investigated. The distribution of solubility quotients for kaolinite-smectite reactions showed the trend of reaching at equilibrium with Ca-, Mg-, and Na-smectite for deep groundwaters in granitic aquifers. The values of $10^{-14.56}$, $10^{-15.73}$, and $10^{-7.76}$ were proposed as equilibrium constants between kaolinite and Ca-, Mg-, and Na-smectite end members, respectively. On stability diagrams, most of deep groundwaters were located at equilibrium boundaries between stability fields of kaolinite and smectites or on stability fields of smectites and illite. Shallow groundwaters in basic rock aquifer were plotted at the same stability areas of deep granitic groundwaters on stability diagrams. The results indicated that the primiary mineralogical composition may be important to predict weathering products in deep aquifers.

• Applied Chemistry for Engineering
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• v.4 no.4
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• pp.672-682
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• 1993

2, 4-Heptadione(abbreviated to 24HTD) was synthesized from methylpropyl ketone and ethyl acetate with sodium amide, and the equilibrium and the kinetic characteristics of copper extraction by 24HTD-chloroform were investigated. Equilibrium constants such as the dissociation constant and the distribution coefficient of 24HTD and the stability constant of the 24HTD-Cu chelate were evaluated from the spectrophotometry, and the overall equilibrium constant of the extraction was also determined. The extracted species of the 24HTD-Cu chelate was found to be $CuR_2$ and the initial rate of the extraction of coupper by 24HTD in chloroform was expressed by $R_0=k[\bar{HR}]([Cu^{2+}]/[H^+])^{0.5}$.

• Resources Recycling
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• v.17 no.2
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• pp.63-69
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• 2008

The adsorption features of $Ni^{2+}$ onto spent alkaline manganese batteries powder have been investigated with the adsorbent dose, initial concentration of adsorbate and temperature as the experimental variables. The adsorption reaction of $Ni^{2+}$ ion followed the pseudo-second order rate model, and the adsorption rate constants($k_2$) decreased with increasing initial concentration of nickel ion. The equilibrium adsorption data were fitted to the Langmuir and Freundlich models. The Freundlich model represents the equilibrium data better than the Langmuir model in this initial adsorbate concentration range. As the temperature increased, the adsorbed amount of nickel ion at equilibrium was also increased, which indicated that the adsorption reaction was endothermic. Based on the experimental results obtained along with temperatures, thermodynamic parameters such as ${\Delta}H^{\circ},\;{\Delta}G^{\circ},\;and\;{\Delta}S^{\circ}$ were calculated.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1873-1878
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• 1991

An high-speed isothermal calorimeter which can trace the progress of a liquid phase reversible reaction was constructed using analog and digital computer. By means of a set point change of the calorimeter, the thermal energy capacity and the heat of reaction in reversible reaction mixture can be measured. The heat of reaction between 2-methyl furan and maleic anhydride and the heat capacities of the adduct were 61,200 J/mol and 2.38 J/ g K, respectively. Also reaction equilibrium constant and reaction rate constants can be estimated from the response curves of the calorimeter.

• Transactions of the Korean Society of Mechanical Engineers
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• v.5 no.2
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• pp.122-130
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• 1981

Equation of equilibrium is derived and solved for an infinite isotropic solid under applied hydrostatic stress which is uniform at large distance, and disturbed by a spherical precipitate which has isotropoc elastic constants dirrerent form those of the matrix. A linear strain hardening behavior of the matrix is assumed, and an elasto-plastic sloution is obtained. The difference of the total strain energy stored inthe infinite solid with and without a precipitate is computed, and compared with that for purely elastic case. Finally the effect of the ratio of the bulk modulus of the precipitate to that of the matrix and the effct of linear strain hardening rate on the plastic zone size and the energy difference are discussed.

• Environmental Engineering Research
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• v.10 no.4
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• pp.199-204
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• 2005

Experiments were performed to estimate the organic release from the aquifer soil in riverbank and/or riverbed filtration via a kinetic approach. Organic release was assumed as a reaction of first order regarding concentrations in both soil and water phases. The reaction rate constants were obtained by comparing the model predictions with the experimental data of organic release reaction and the equilibrium distribution of organic matter between water and soil phases. Results show that the organic release from the aquifer soil was not negligible under normal conditions in Korea reaching 4.7mg-COD/L-day. This indicates that manganese and iron start to be released from aquifer soil in the riverbank filtration in the middle reach of the Nakdong river if the travel time of the filtrate exceeds about 5 days. It was also seen that the COD of the soil organic matter was 0.89mg-COD/mg-OM and that 65% of the COD was BOD5.

• Archives of Pharmacal Research
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• v.27 no.9
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• pp.978-983
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• 2004

The effects of glycyrrhizic acid (GLZ) on protein binding of diltiazem, verapamil, and nifedipine were investigated. Protein binding studies (human serum, human serum albumin (HSA) and (X1-acid glycoprotein (AAG)) were conducted using the equilibrium dialysis method with and without addition of GLZ. The binding parameters, such as the number of moles of bound drug per mole of protein, the number of binding sites per protein molecule, and the association con-stant, were estimated using the Scatchard plot. The serum binding of nifedipine, verapamil, and diltiazem was displaced with addition of GLZ, and the decreases of Ks for serum were observed. GLZ decreased the association constants of three drugs for HSA and AAG, while the binding capacity remained similar with addition of GLZ. Although the characteristics of interaction were not clear, GLZ seemed to mainly affect HSA binding of nifedipine rather than AAG binding, while GLZ seemed to affect both AAG- and HSA-bindings of verapamil and dilt-iazem resulting in a serum binding displacement.

• The Korean Journal of Ecology
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• v.10 no.3
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• pp.139-149
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• 1987

Mathematical models of the litter accumulation, decay and turnover in the grassland and forest ecosystems of equilibrium state of the annual litter production were established to analyse the decay rates of organic and inorganic constituents of the litter. Those models were validated by an application to a Phragmites longivalvis grassland in a delta of the River Nakdong. The decay constants of cold-water-soluble fractions, other carbohydrates, hot-water-soluble fractions, cellulose, crude fat, lignin and crude protein in the litter were 0.730, 0.583, 0.555, 0.505, 0.479, 0.331 and 0.310 respectively. The amount of mineral nutrients such as N. P. K. Ca and Mg returned annually to the soil were estimated to 7.09, 1.34, 2.36, 4.37 and 0.79g/m2 respectively.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.114-122
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• 2000

Several new ion exchange resins have been synthesized from chloromethyl styrene-1,4-divinylbenzine with 1%, 2%, 5% and 105-crosslink and macrocyclic ligands of cryptand type by interpolymerization method. The adsorption characteristics and the pH, time, solvents and concentration dependence of the adsorption of uranium ion by this resins were studied. The resins were very stable in both acidic and basic media and have good resistance to heat at $300^{\circ}C$. The uranium ion are not adsorbed on the resins below pH 3.0, but the power of adsorption of it increased rapidly above pH 4.0. The optimum equilibrium time for adsorption of uranium ion was two hours and adsorptive power decreased in proportion to crosslink size of the resins and order of dielectric constants of solvents used and the adsorption for uranium ion was bin the order of $OdienNtn-H_4$ > $OtnNen-H_4$ > $OtnNen-H_4$ > $OenNen-H_4$.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1996.11a
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• pp.50-53
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• 1996

This paper reports the experimental results for the determination of the overall partition coefficient of VOCs in unsaturated soil, A chromatographic method was used for the determination of gaseous partition coefficients to natural soil under various water content conditions. The equilibrium vapor pressure of water over saturated salt solution was used to fix the relative humidity of the air and control the water content of the soil systems. The transport behavior was studied for dichloromethane, trichloroethane and dichlorobenzene pollutants, with log octanol-water partition coefficients(log $K_{ow}$ ) which range from 1.25 to 3.39, or water to soil partitioning which varies by 135 times; water solubility constants which vary by 3 times; and vapor pressures which range from 1 to 362 torr. Water content of the soil had a pronounced effect on the effective partition coefficient(between gas and soil + water stationary phase) as well as on the effective dispersion coefficient.