• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.219-225
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• 2007

The equilibrium solubilization capacity of pure hydrocarbon oils by 2.5 wt% $C_{12}E_8$ nonionic surfactant solution was measured at $30^{\circ}C$ by gas chromatography (GC) analysis. Experimental results indicated that the molar solubilization ratio (MSR) for pure alkanes was found to decrease almost linearly with the alkane carbon number (ACN) of the hydrocarbon oil. For the binary mixture systems of the hydrocarbon oils both selective and nonselective solubilization behaviors were observed depending on the difference in carbon number of the two hydrocarbon oils. Equilibrium solubilization tests for the two n-octane/n-nonane and n-nonane/n-decane mixture systems in $C_{12}E_8$ surfactant solutions suggest slightly selective solubilization in favor of n-octane, but the small difference in solubilization rates between two hydrocarbon oils does not allow ruling out non-selective solubilization for these particular systems. This is certainly not the case for the n-octane/n-decane mixture, for which selective solubilization was conclusively demonstrated by GC analysis data.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.2
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• pp.356-365
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• 1995

study was made to investigate the emulsification and rolling-up between liquid oily soils and surfactant and its effect on the detergency. Samples used were triolein as a triglyceride, oleic acid as a free fatty acid and sodium dodecyl sUJfate(SDS) as a surfactant. The results were as follows: 1. The spontaneous emulsification occurred in the system of oleic acid alone and mixture of triolein and oleic acid contacted with 0.5% SDS solution, but it did not occurred in a case of triolein alone. 2. The stability of emulsification increased with the increase of SDS concentration. And the stability of emulsification and (-) t value increased in the order of triolein < mixture of triolein and oleic and< oleic acid. 3. The rolling-up mechanism of model oily soils easily occurred in the order of triolein< mixture of triolein and oleic acid< oleic acid, and facilitated with the increase of SDS concentration. On the other hand, the complex formation was already observed in the system of oleic and 0.5% SDS solution. 4. As compared with the detergency of triolein, the detergency of oleic acid was very high. And the detergency of mixed soil was improved with increasing ratio of oleic acid in the mixture.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.75-76
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• 2024

The ovicidal effect of plant extract mixture (5%cinnamon extract + 10% citronella oil + 30% citrus oil + 10% derris extract + 20% neem extract + 25% penetrating surfactant) against several major insect pests was tested using the spraying method. In the case of stink bugs, eggs tended to die during hatching. When treated with a plant extract mixture (500-times solution), mortality for Halyomorpha halys, Riptortus clavatus, Eurydema dominulus, Trialeurodes vaprarorium, Bemisia tabaci, Spodoptera exigua, and Agrotis ipsilon reached as high as 100%. Therefore, it is believed that industrialization will be feasible in the future.

• Journal of the Korean Applied Science and Technology
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• v.28 no.1
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• pp.95-101
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• 2011

We estimated on the stability of W/O type emulsified fuel using by capacitance sensor, so it concluded the following conclusions. For the first 24 hours, prepared emulsified fuel reveals phase separation ratio of 5%, maintains stable status which verifies the stability of emulsified fuel. Adding more water increases the phase separation ratio rapidly, and adding more surfactant displays stable emulsification. Adding water causes larger size of water droplet diameter, and adding surfactant mixture causes smaller size of water droplet diameter. In conclusion, the size of W/O type emulsified fuel water droplet diameter is directly related to the volume of surfactant, and density of water droplet diameter changes thedistribution according to water contents.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.2 s.245
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• pp.179-186
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• 2006

Dielectrophoresis has received considerable attention for separating nanotubes according to electronic types. Here we examine the effects of surface conductivity of semiconducting single-walled carbon nanotubes (SWNT), induced by ionic surfactants, on the sign of dielectrophoretic force. The crossover frequency of semiconducting SWNT increases rapidly as the conductivity ratio between the particle and medium increases, leading to an incomplete separation of ionic surfactant suspended SWNT at an electric field frequency of 10 MHz. The surface charge of SWNT is neutralized by an equimolar mixture of anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant cetyltrimenthylammonium bromide (CTAB), resulting in negative dielectrophoresis of semiconducting species at 10 MHz. A comparative Raman spectroscopy study shows a nearly complete separation of metallic SWNT.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.979-984
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• 2008

In this study, 8 solutes (aniline, caffeine, p-cresol, ethyl benzene, methylparaben, phenol, pyridine, and toluene) have been tested in terms of linear solvation energy relationships (LSER). Several micellar liquid chromatography (MLC) systems using cationic surfactant cetyltrimethylammonium bromide (CTAB) and a mixture of water with (methanol, n-propanol, and n-butanol) modifiers were characterized using the LSER solvation parameter model. The effects of the surfactant and modifier concentration on the retention in MLC were discussed. LSER model had demonstrated high potential to predict retention factors with high squared correlation coefficients ($r^2$ > 0.99). A comparison of predicted and experimental retention factors suggests that LSER formalism is able to reproduce adequately the experimental retention factors of the solutes studied in the different experimental conditions investigated. This model is a helpful tool to understand the solute-surfactant interactions and evaluate the retention characteristic of micellar liquid chromatography.

• Journal of Surface Science and Engineering
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• v.40 no.1
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• pp.16-22
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• 2007

Recently, mesoporous metallic materials are becoming more and more important in various applications like catalysts, electrochemical detectors, batteries, and fuel cells because of their high surface area. Among the various methods for manufacturing mesoporous structure, surfactant templating method followed by electroplating has been tried in this study. A mesoporous metallic film was prepared by electrodeposition from electroplating solution mixed with surfactant template. Nonionic type lyotropic liquid crystalline surfactant, Brij56, and nickel acetate based solution were selected as a template material and electroplating solution, respectively. To determine the content of surfactant forming a hexagonal column structure, the phase diagram of electroplating solution and surfactant mixture has been exploited by polarized optical microscopy equipped with heating and cooling stage. Nickel films were electroplated on Cu foil by stepwise potential input method to alleviate the concentration polarization occurred during the electroplating process. TEM and XRD analyses were performed to characterize the size and shape of mesostructures in manufactured nickel films, and electrochemical characterization was also carried out using cyclic voltammetry.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.349-356
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• 2002

In this research, phenol was selected as a representative hydrophilic organic compound and phenanthrene as a representative hydrophobic organic contaminant in petroleum. Fine-grained soil which was manufactured artificially in laboratory was contaminated and EK remediation tests were executed. Also, in order to increase removal efficiency, the surfactant that had been used with improvement technique at the pump-and-treat was used by enhanced method. In the test, the phenol which has high solubility is easily removed, but phenanthrene which has low solubility is almost not. Also, it seems to be the delay phenomenon that the phenanthrene is accumulated near the cathode department vicinity at the enhanced technique which applied the surfactant, but the removal efficiency increases as the surfactant concentration increases. By the test which increases with time, the enhanced method with increasing time is more efficient than the method with increasing surfactant.

• Korean Journal of Materials Research
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• v.29 no.10
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• pp.639-646
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• 2019

Ink-jet printing is a manufacturing process technology that directly prints a digitalized design pattern onto a substrate using a fine ink jetting system. In this study, environmentally friendly yellow aqueous ceramic ink is synthesized by mixture of distilled water, yellow ceramic pigment and additives for ink-jet printing. The graft polymer, which combines electrostatic repulsion and steric hindrance mechanism, is used as a surfactant for dispersion stability of aqueous ceramic ink. Synthesized ceramic ink with graft polymer surfactant shows better dispersion stability than did ceramic ink with PAA surfactant; synthesized ink also shows desirable ink-jet printability with the formation of a single ink droplet during printability test. Finally, ceramic ink printed on glass substrate and ceramic ink with graft polymer surfactant shows a high contact angle without surface treatment on glass substrate. Consequently, it is confirmed that the ceramic ink with graft polymer surfactant can achieve high printing resolution without additional surface treatment process.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.3
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• pp.425-425
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• 1995

The interaction and detergency between liquid oily soil and surfactant solution were studied by the mechanism of formation of liquid crestal(LC). Samples used were triolein as a triglyceride, oleic acid as a free fatty acid and sodium dodgily sulfate (SDS) as a surfactant. The results were as follows: In the phase diagram of SDS/oil/Water system, the area of liquid crystalline phase region were in the order of SDS/trillion/water< SDS/oleic acid/water< SDS/mixture of trillion and oleic acid/water. In the system of oleic acid alone or mixture of trillion and oleic acid contacted with SDS solution, the LC phase was formed right after or after some time with SDS concentration. But in a case of trillion alone, the LC phase was not formed although the concentration of the SDS solution was relatively high. The detergency of model oily soils were seldom changed with temperature, and the detergency of oleic acid was very high compared to that of the trillion. The detergency of mixed soil was improved with the increase of the ratio of oleic acid in the mixture.