• Reproductive and Developmental Biology
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• v.30 no.1
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• pp.13-19
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• 2006

To search of new porcine pheromonal odorants for biostimulation control system technologies to improve reproductive efficiency in livestock species, the comparative molecular field analysis (CoMFA) for binding affinity constant $(p(Od)_{50})$ between porcine odorant binding protein (pOBP) and ligands of odorant 2-(cyclohexyloxy) tetrahydrofurane derivatives as substrate molecule was conducted and discussed. In the optimized CoMFA model AIV with chirality $(C_1'(R),\;C_2(S))$ in substrate molecule and atom based fit alignment (A) of odorants, the statistical results showed the best predictability of the binding affinities $(p(Od)_{50})$ based on the LOO cross-validated value $r^2_{cv}.\;(q^2=0.886)$ and non-cross-validated conventional coefficient $(r^2_{ncv}.=0.984)$. the binding affinity constants exhibited a good correlation with steric (40.8%), electrostatic (14.6%) and hydrophobic (44.6%) factors of the substrate molecules. from the analytical results of the contour maps, which may give us some valuable informations to the modification of odorants for effective binding affinity.

• Korean Chemical Engineering Research
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• v.54 no.2
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• pp.239-247
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• 2016

This study aims to examine absorption characteristics of toluene, isopropyl alcohol (IPA), ethyl acetate (EA), and ternary-compounds, all of which are widely used in industrial processes, by means of four types of commercial activated carbon substances. It turned out that among the three types of volatile organic compounds, the breakthrough point of activated carbon and that of IPA, whose affinity was the lowest, were the lowest, and then that of EA and that of toluene in the order. With the breakthrough point of IPA, which was the shortest, as the standard, changes in the breakthrough points of unary-compounds, binary-compounds, and ternary-compounds were examined. As a result, it turned out that the larger the number of elements, the lower the breakthrough point. This resulted from competitive adsorption, that is, substitution of substances with a low level of affinity with those with a high level of affinity. Hence, the adsorption of toluene-IPA-EA and ternary-compounds require a design of the activated carbon bed based on the breakthrough of IPA, and in the design of activated carbon beds in actual industries as well, a substance whose level of affinity is the lowest needs to be the standard.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.532-540
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• 2019

PET microfibers with various diameters (0.5, 0.2, 0.06, and 0.01 dpf) were dyed with a dispersed dye (C.I. Disperse Blue 56) at various temperatures. The dyeing process was conducted under infinite dyebath conditions at constant temperatures. The effects of the dyeing temperature and diameter on the partition coefficient, affinity, and diffusion coefficient of disperse dyes were studied. The curve of isotherms was fitted well to Nernst-type model in a large range of initial dye concentrations. At the same temperature, the partition coefficient and affinity decreased with increasing sample diameter due to the increase in surface area. At all deniers, the partition coefficient and affinity decreased with increasing temperature because the dyeing process is an exothermic reaction. In addition, the decrease in radius of the sample gives rise to a decrease in the heat of dyeing. The fine diameter of the sample resulted in an increased surface area but decreased space between the microfibers. Consequently, decreasing the diameter of the microfibers leads to a decrease in the diffusion coefficient. At the same diameter, the diffusion coefficient increased with increasing temperature because of rapid dye movement and the large free volume of the sample inside. In addition, thermal dependence of the diffusion coefficient increased when the diameter of the sample increased.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2005.05a
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• pp.136-138
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• 2005

• Journal of the Korean Society of Food Science and Nutrition
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• v.10 no.1
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• pp.67-76
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• 1981

By using the paper chromatograph technique affinity of amino acids to the mercury was compared with that of sodium thiosulfate, 2,3-dimercaptopropanol(BAL) and inosinic acid. Among the amino acids of testment three acids (Cysteine, Cystine and Methionine) which posses sulfide or disulfide radical exhibited a spot which combined more apparently with the mercury than other amino acids. However, in the mixed solutions of thiosulfate, BAL or inosinic acid with those amino acid and mercury, the mercury was moved into thiosulfate, BAL or inosinic acid spot. It was clear from the results that affinity of sodiume thiosulfate, BAL and inosinic acid to the mercury is higher than that of amino acids.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.533-538
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• 2008

In order to enhance the adsorption capacity of $CO_2$, a commercial zeolite and coal fly ash were chemically modified with alkali cations (Li, K) and alkaline-earth cations (Ca, Mg). Adsorbents containing Ca and Mg showed slightly lower surface areas. The adsorption capacity at the ambient temperature was highest with Ca, then in order of Mg, Li, and K. On the contrary, regeneration efficiency of the adsorbents with Ca and Mg was relatively low, because Ca and Mg cations had stronger affinity of carbon dioxide. The affinity between cations and $CO_2$ molecule also may improve the selectivity in favor of $CO_2$ adsorption.

• Membrane Journal
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• v.9 no.2
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• pp.107-113
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• 1999

Alcohol concentration via pervaporation process was performed by using commercial PDMS(polydimethylsiloxane) composite membrane and plasma treated PP(polypropylene) membranes. Effects of operating parameters of pcrvaporation process were examined. With the increase of butanol concentration in the feed, flux and selectivity increased due to the greater affinity of butanol with PDMS than that of water. As the operating temperature increased, free volume as well as the solubilities and diffusivities of alcohol and water increased to result in the greater flux and less selectivity of the membrane. As solubility parameter difference between alcohol and PDMS membrane decreased, high flux and good selectivity were obtained. When PP membrane was plasma treated with methanol, it has 6 times greater flux than PDMS membrane with equivalent separation factor. With the increase of plasma treatment time, flux and selectivity were enhanced. However, excess treatment time caused pore blocking to result in the flux decrease.

• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.28-36
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• 2018

Adsorption experiments of three target gases such as acetone, benzene, and methyl mercaptan (MM) were carried in a continuous reactor using the activated carbon prepared from waste citrus peel. In a single gas system, the breakthrough time obtained from using the activated carbon (WCAC) prepared from waste citrus peel. In a single gas system, the breakthrough time obtained from the breakthrough curve decreased with increasing the inlet concentration and flow rate, but increased with respect to the aspect ratio (L/D). Adsorbed amounts of the target gases by WCAC increased as a function of the inlet concentration and aspect ratio. However, adsorbed amounts with the increase of the flow rate were different depending upon target gases. Results from the breakthrough time and adsorbed amount showed that the affinity for WCAC was the highest in benzene, followed by acetone and then MM. On the other hand, in the binary and ternary systems, the breakthrough curve showed a roll-up phenomenon where the adsorbate having a small affinity for WCAC was replaced with the adsorbate with a high affinity. The adsorption of acetone on WCAC was more strongly affected when mixing with the nonpolar benzene than that of using sulfur compound MM.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.274-280
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• 2009

In order to elucidate the adsorption mechanism of the herbicide, bentazon and its metabolites on soil, their adsorption patterns on soil and six adsorbents were investigated with Freundlich, Langmuir and linear isotherm. Freundlich constants ($K_f$) and maximum adsorption amount($Q^0$) of bentazon on soil was 0.55 and 3.97. Kd and Koc values of it were 0.18 and 18. The all of metabolites used except deisopropylbentazon amounts sorbed on the soil were much higher than bentazon. The most of 8-hydroxybentazon was adsorbed on soil showing $K_f$ = 316.6, $Q^0$ = 3,488, Kd = 29.7 and Koc = 2,970. Bentazon, deisopropylbentazon and 8-hydroxybentazon were shown high affinity to anion exchange regardless of pH and $NH_2$ in low pH range. Reversed phase $C_{18}$ resulted in 100% retention of N-methylbentazon regardless of pH and other metabolites were retained below 40%. The AIBA was strongly adsorbed in silica gel, COOH and cation exchange phase but poor retention was on anion exchange sorbent. 2-Aminobenzoic acid showed an amphipathic nature which had high affinity for COOH and cation exchange phase at pH 7.0 as well as $NH_2$ and anion exchange sorbent at pH 3.0.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.4
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• pp.106-127
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• 2010

Although multi-layer planting methods are more widely used as a method for clustered planting and environmental programs such as plant remediation, difficulties have been faced in applying those to planting design. This study develops a basic planting model that can be applied to multi-layer planting in basis on an analysis of forest structures in the Seoul area. An optimal number of clusters was determined through the ISA (Indicator Species Analysis), and 7 basic clusters were found through a cluster analysis by using PC ORD 4.0 software specifically developed for ecological analysis. The 7 basic clusters include the following communities: the Quercus acutissima Community, Sorbus alnifolia-Quercus mongolica Community, Pinus rigida-Pinus densifiora Community, Rododendron mucronulatum var. mucronulatum-Quercus mongolica Community, Juniperus rigida-Quercus mongolica Community, Rododendron mucronulatum var. mucronulatum-Pinus densiflora Community, and Rododendron sclippenbachii-Quercus mongolica Community. The study also selected 57 species with at least a 10% frequency among the plant species existing in the Seoul area and suggested both a companion species and available similar alternative species by conducting an additional interspecific association analysis. This study may help to enhance usefulness of the model in architectural planting design. In addition, the two results named above were synthesized to develop a multi-layer planting model that can be utilized in landscape planting design by selecting similar alternative species through the interspecific association analysis, which includes 7 clusters of natural plants. The multi-layer planting model can be widely applied to design planting because the model has an average target cover range based on the average value of a transformed likelihood.