• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.65-66
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• 2006

Solubility of single wall carbon nanotubes (SWNTs) has been determined in various dispersing media by using the solvent parameters such as Kamlet-Taft parameter and 3-dimensional parameters. Nitric acid-treated SWNTs exhibit significantly improved solubility in hydrogen bondable solvents as well as in solvent mixtures. The forming bucky gel with ionic liquid allows for the new group of dissolving solvent. The dissolution behavior of SWNTs provides a route for SWNT dispersion/exfoliation in preparing electrically conductive films such as transparent electrode.

• Nuclear Engineering and Technology
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• v.29 no.2
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• pp.127-137
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• 1997

Equilibrium concentrations of major elements in an underground repository with a capacity of 100,000 drums have been simulated using the geochemical computer code (EQMOD). The simulation has been carried out at the conditions of pH 12 to 13.5, and Eh 520 and -520 mV. Solubilities of magnesium and calcium decrease with the increase of pH. The solubility of iron increases with pH at Eh -520 mV of reducing environment while it almost entirely exists as the precipitate of Fe(OH)$_3$(s) at Eh 520 mV of oxidizing environment. All of cobalt and nickel are predicted to be dissolved in the liquid phase regardless of pH since the solubility limit is greater than the total concentration. In the case of cesium and strontium, all forms of both ions are present in the liquid phase because they have negligible sorption capacity on cement and large solubility under disposal atmosphere. And thus the total concentration determines the equilibrium concentration. Adsorbed amount of iodide and carbonate are dependent on adsorption capacity and adsorption equilibrium constant. Especially, the calcite turns out to be a solubility-limiting phase on the carbonate system. In order to validate the model, the equilibrium concentrations measured for a number of systems which consist of iron, cement, synthetic groundwater and radionuclides are compared with those predicted by the model. The concentrations between the model and the experiment of nonadsorptive elements cesium, strontium, cobalt nickel and iron, are well agreed. It indicates that the assumptions and the thermodynamic data in this work are valid. Using the adsorption equilibrium constant as a free parameter, the experimental data of iodide and carbonate have been fitted to the model. The model is in a good agreement with the experimental data of the iodide system.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.1
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• pp.9-13
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• 2016

Micelles, which are called solubilization formulation, have been widely used in skin lotion, mist or various formulations for the purpose of solubilizing the fragrance rather than the role of the active ingredient carrier because the particles are very small. In this study, we developed the swollen micelle having a transparent appearance to deliver ${\beta}$-sitosterol. When preparing the swollen micelle, solubility parameter was considered with active ingredient. This method allowed insoluble active ingredient to be safely entrapped inside the micelles. Stability of micelle was evaluated by dynamic light scattering (DLS). The transparency and shape of the micelles were confirmed by cryo-TEM. In addition, through the thermal analysis using DSC, ${\beta}$-sitosterol was found to be stably present in the swollen micelles. These results indicate that swollen micelles considered solubility parameter could be used as a new carrier for the insoluble active ingredients.

• Journal of Adhesion and Interface
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• v.2 no.3
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• pp.9-15
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• 2001

To estimate the effect of the surface state of the EVA foam on an adhesion, the surface was treated with solvents having different values of a solubility parameter and a surface tension. The morphology and the contact angle were measured by SEM and contact angle tester, respectively. The value of the critical surface tension(${\gamma}_{c,0}$) of the EVA foam calculated by Zismann plot was 27.08 dyne/cm. The surface state and the ${\gamma}_c$ of the EVA foam were changed by solvent treatment. The swelling ratio of EVA foam was influenced by solubility parameter of a solvent, on the other hand the degree of change in the surface state was dependent on a surface tension of a solvent. When a surface tension of solvent. When a surface tension of solvent is lower than ${\gamma}_{c,0}$ of the EVA foam, the wettability of a solvent was good and the surface state was greatly changed. The adhesion strength of EVA foam was greatly improved to above 600% as compared to that of the untreated one. As the ${\gamma}_c$ of EVA was closed to the surface tension of the primer, the good adhesion strength was obtained.

• Restorative Dentistry and Endodontics
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• v.36 no.2
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• pp.139-148
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• 2011

Objectives: This study investigated the effect of the strength and wetting characteristics of adhesives on the bond strength to dentin. The experimental adhesives containing various ratios of hydrophobic, low-viscosity Bis-M-GMA, with Bis-GMA and TEGDMA, were made and evaluated on the mechanical properties and bond strength to dentin. Materials and Methods: Five experimental adhesives formulated with various Bis-GMA/Bis-MGMA/TEGDMA ratios were evaluated on their viscosity, degree of conversion (DC), flexural strength (FS), and microtensile bond strength (MTBS). The bonded interfaces were evaluated with SEM and the solubility parameter was calculated to understand the wetting characteristics of the adhesives. Results: Although there were no significant differences in the DC between the experimental adhesives at 48 hr after curing (p > 0.05), the experimental adhesives that did not contain Bis-GMA exhibited a lower FS than did those containing Bis-GMA (p < 0.05). The experimental adhesives that had very little to no TEGDMA showed significantly lower MTBS than did those containing a higher content of TEGDMA (p < 0.05). The formers exhibited gaps at the interface between the adhesive layer and the hybrid layer. The solubility parameter of TEGDMA approximated those of the components of the primed dentin, rather than Bis-GMA and Bis-M-GMA. Conclusions: To achieve a good dentin bond, a strong base monomer, such as Bis-GMA, cannot be completely replaced by Bis-M-GMA for maintaining mechanical strength. For compatible copolymerization between the adhesive and the primed dentin as well as dense cross-linking of the adhesive layer, at least 30% fraction of TEGDMA is also needed.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3485-3488
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• 2012

• Textile Coloration and Finishing
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• v.2 no.1
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• pp.21-30
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• 1990

In order to obtain high dye uptake initially, polyethylene terephthalate (PET) filaments were dyed with C.I.Disperse Orange 3 and Red 1 in mixed solvents of tetrachloroethylene acidic solvent, ethyl alcohol and tetrachloroethylene basic solvent, DMF. The dyeing behavior in the mixed solvent of tetrachloroethylene and basic solvent, DMF, the initial uptake of disperse dyes increased rapidly. The shrinkage of PET increased when the solubility parameter values of PET fiber and mixed solvent approached graduately.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.581-587
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• 2005

In order to obtain a highly purified p-dioxanone (PDX) as monomer of biodegradable polymer, suitable solvent must be selected. The selection was based on the solubility of impurities, and partial layer melt crystallization were carried out under the presence of solvent. The solubility of PDX in various solvents such as ethyl acetate, tetrahydrofuran, acetone, alcohols (methanol, ethanol, 1-propanol, 1-butanol and 1-pentanol) were measured over the temperature range of $-10{\sim}15^{\circ}C$. As solubility parameters, the mixing and dissolution enthalpy between the PDX and the solvents was studied based on empirical equations and the regular solution theory. The solubility and the temperature dependency of the solubility with the solvents of acetone, ethylacetate, and tetrahydrofuran of PDX were shown to have relatively high values compared to the alcohol type solvents. Also, in same alcohols, the smaller molecules and higher polarity gave higher solvency. In partial layer melt crystallization, small amount of ethylacetate selectively dissolved impurities and gave highly purified p-dioxanone, over 99.9% purity.

• Journal of radiological science and technology
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• v.24 no.1
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• pp.43-48
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• 2001

This study deals with the relationship between the magnitude of ultrasonic nonlinear parameter B/A, and sound speed of amount of fat present in biological media to measure B/A system using a wide band ultrasonic transducer. To represent this case, mixtures of egg whites and egg yolk were studied. Even though the differences in density and sound speed of the two egg components were in the range of 1%, B/A increase parabolically as a function of the fat density, which is not in agreement with the Yoshizumi et al's suggestion. In skim milk that does not contain fat, both the B/A and the sound speed increase with the solubility. It is considered that protein could affect these values.

• Elastomers and Composites
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• v.43 no.4
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• pp.230-240
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• 2008

In order to synthesize polymer particle containing inorganic material, styrene and nbutylmetacrylate were copolymerized with alumina by dispersion polymerization. The ratio in weight of styrene to n-butyl methacrylate was 3:1. Poly(N-vinyl pyrrolidon) and 2,2'-azobis(isobutyronitrile) were added as stabilizer and as initiator, respectively. The change of particle size was investigated with concentration of initiator, the type of medium, the mixed solubility parameter (${\delta}_{mix}$) of medium, and coupling agent. The enhancement in concentration of initiator resulted in slight increase of particle size. The increase of polarizability in medium also yielded the increase of particle size. In case of changing the ratio of isopropanol to distilled water, we could find relationship of $[{\delta}_{mix}]^{-4.01}\;{\propto}$ particle size and $[{\delta}_{mix}]^{-0.83}\;{\propto}$ particle size distribution(PSD). The type and the concentration of coupling agent showed no effect on the particle size and PSD.