• Journal of the Korean Ceramic Society
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• v.35 no.6
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• pp.594-602
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• 1998

Titanium hydroxide (TiO({{{{ {OH }_{2 } }})) fine particles were produced by the reverse micelle technique. For the formation of titanium hydroxide (TiO({{{{ {OH }_{2 } }})) particles with the technique reversed micellar solution was prepared by solubilizing water into organic solvent (isooctane) with a surfactant and titanium alkoxide (tetraisopropyl orthotitanate) diluted with isopropyl alcohol was added to the reversed micellar solution. The hdrolyzed species (TiO({{{{ {OH }_{2 } }})) was formed by the hydrolysis of titanium alkoxide and titanium dioxide is then formed by the condensation of the hydrolyzed species. There are several process variables such as surfactants concentration of surface cosurfactant hydrolysis temperature and pH. In this work the ef-fects of process variables on paticle shapes particle size distribution and paticle agglomeration were bi-nodal for an anionic surfactant(AOT) in the whole range of temperature pH and surfactant concentration of this experiment. The addition of ethanol as a cosurfactant resulted in narrow particle size distribution of the experiment. The additiono of ethanol as a cosurfactant resulted in narrow particle size distribution and 0.12${\mu}{\textrm}{m}$ of smaller average particle diameter. FT-IR spectrum of particles shows the absorption peak of Ti-OH bonding and Ti-O bonding. An exothermic peak around 41$0^{\circ}C$ in TGA-DTA curve shows that crys- tallized anatase phase appears and completely transits to anatase around 45$0^{\circ}C$.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.423-431
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• 1993

Long chain alcohols, the mixtures of 1-hexadecanol/1-octadecanol, were used as cosurfactants for O/W emulsion prepared with glycerol monostearate/POE(100) monostearate mixed nonionic surfactants, and the phase behavior and flow properties of O/W emulsions were observed. The transition temperature of long chain alcohol was varied with the composition of 1-hexadecanol/1-octadecanol and had the lowest value when the mixed ratio of 1-hexadecanol/1-octadecanol was 2/1. The liquid crystalline phase was formed as the addition of long chain alcohol and the secondry droplet, the flocculate of the emulsion particles, was made, and thus the viscosity of the emulsion was increased. When the temperature of emulsion system was under the transition temperature of long chain alcohol, the mobility of hydrocarbon group of long chain alcohol was restricted, and thus gel structure was formed and the viscosity of the the O/W emulsion was increased, but along with the time, the liquid crystalline phase was disappeared and the viscosity of emulsion was decreased. Long chain alcohol/nonionic surfactants/water formed the liquid crystalline phase when the long chain alcohol was added above the saturation point of solution(2 wt% in this experoment), and the secondry droplet didn't formed when the long chain alcohol was added more than a certain amount (10 wt% in this experiment).

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.533-541
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• 2005

Non-aqueous cleaning agents were formulated with 2,2,2-trifluoroethanol (TFEA) and hydrofluoroether (HFE), and their physical properties and cleaning abilities were examined. TFEA-based aqueous cleaning agents were also formulated with nonionic surfactants, hydrotropes and builders, and their cleaning abilities were compared. Possibilities of these cleaning agents as substitutes for CFC-113 and 1,1,1-TCE were finally evaluated. In this work, fluxes, cutting oils, greases, and fluoric oils were selected as model contaminants for cleaning experiments. These contaminants have different properties of water-solubility or hydrophilicity, and fat-solubility or lypophilicity. Cleaning abilities of TFEA-based cleaning agents were analyzed and compared through the measurement of contaminant weight changes as a function of cleaning time, and their possibilities as alternative cleaning agents were evaluated. As a result, it was shown that TFEA and HFE-based non-aqueous cleaning agents have quite a good cleaning power for fluxes and fluorine soils but low one for greases. And TFEA-based agueous cleaning agents which consisted of nonionic surfactants, hydrotrope, and builders were very effective for cleaning fluxes and greases under certain formulation conditions. Thus, it was revealed that the TFEA-based cleaning agents were very effective for cleaning specific contaminants and can be used as substitutes for CFC-113 and 1,1,1-TCE in some industrial applications.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.9_10
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• pp.1153-1159
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• 2003

The effects of changing aqueous solution properties by nonionic surfactants on wetting behavior and water retention properies of hydrophobic PET (polyethylene terephthalate) fabric were reported. The aqueous solution properties were diversified by mixing and diluting two nonionic surfactants, i.e., sorbitan monolaurate (Span 20) and polyoxyethylene(20) sorbitan monolaurate (Tween 20). The surface wetting properties ($cos{\theta}$) of PET fabric were greatly improved by adding $10^{-1}g/dl$ Tween 20 and further improved by mixing Span 20 to the system. The water retention properties (W) of PET fabric were also greatly increased by addition of $10^{-1}g/dl$ Tween 20. In diluted surfactant systems, the $cos{\theta}'s$ were increased with decreasing surface tension of aqueous liquids. The ratios of aqueous liquid retained in the pore structure to liquid retention capacity (W/H) were also increased with decreasing surface tension, however, W/H values were dramatically increased right after critical micelle concentration (cmc). The existence of micelles was important for the retention of aqueous liquids in the fabric. The critical surface tension of PET fabric used was found to be 28.7dyne/cm.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.617-623
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• 1997

In this study, the mechanism on the phase behavior of polysorbate nonionic surfactants was investigated. In the ternary system containing water, hexanol as a polar oil and surfactant, the phase behaviors ranging from micellar region to occurrence of liquid crystal phase were observed by crossed microscope. As results, fine mosaic texture of liquid crystal phase and other phases were examined in the range of 20~70 wt%. This range if thought to give information about the basic data for the formulation of more stable emulsifying systems or dispersed systems. According to the alkyl chain length, three phase region diminished, whereas two phase range increased without an observation of the anisotropic liquid crystalline phase.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.246-251
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• 1997

The phase behavior of sucrose monopalmitate/alkanol/water ternary system was investigated. According to compositions of three components ranging from micellar(or inverse micellar) solution up to various lyotropic liquid crystalline(LC) phase, each texture of the separated phases was identified by crossed polarizers equipped with a camera whose stage was connected to a thermostatic circulator. As the carbon atom number in alkanol of the polar oily substance increases, patterns of the various LC phases were also observed hexanol

• Horticultural Science & Technology
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• v.18 no.5
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• pp.612-620
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• 2000

In developing soil wetting agent using polyoxyethylene octylphenyl ether [$C_8H_{17}O(C_2H_4O)_{10}H$, POE], the effect of mixtures of POE and polyoxyethylene+polypropyleneoxide tridecylether (1:1, w/w, CM-1), polyoxyethylene+polypropyleneoxide tridecylether+propyleneglycol monomethylether (1:1:2, w/w/w, CM-2) or glycerin+ditridecyl phthalate (1:1, w/w, CM-3) on changes of concentration of POE, initial wetting, evaporative water loss, water infiltration, and changes of physical properties in root media were determined. The mixtures of POE and CM-1, 2, or 3 with zeolite or vermiculite as carrier had high concentrations of POE in root media during 6 elution times, but those after 6 times decreased rapidly indicating unstable elution of POE. The commercial AquaGro was more effective than the mixtures of POE+CM-1, 2, or 3 in water retention during 18 hours. Root media incorporated with POE+CM-2 held more water than any other treatments at 84 hours after watering, but the differences among treatments except control were not significant. In the treatments with zeolite as a carrier, POE+CM-3 had the greatest evaporative water loss followed by POE+CM-2, AquaGro, control, and POE+CM-2. In the treatments with vermiculite as a carrier, POE+CM-1 had the highest evaporative water loss followed by POE+CM-3, AquaGro, control, and POE+CM-2. In the effect of mixtures with zeolite as a carrier on infiltration of water into root media, the treatment of POE+CM-1 had the highest amount of water infiltrated followed by POE+CM-3, AquaGro, POE+CM-2, and control. In the effect of mixtures with vermiculite as a carrier on infiltration of water into root media, the treatment of POE+CM-3 had the highest amount of water infiltrated followed by AquaGro, POE+CM-1, POE+CM-2, and control.

• Textile Coloration and Finishing
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• v.21 no.2
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• pp.7-13
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• 2009

The effects of 0.1g/dl nonionic surfactant solutions on liquid wetting and retention properties of wool fabric are reported. The 10 different nonionic surfactants (Span 20, Tween 20, 40, 60, 80, 21, 61, 81, 65, 85), wool cloth (EMPA 217), and wool soiled cloth (EMPA 107) are used in the study. Both EMPA 217 and 107 have water contact angle($\Theta$)>$90^{\circ}$, which indicates that water spreading over a fabric surface and penetration into the fabric rarely occur. However, EMPA 217 and 107 are easily wetted with perchloroethylene(PCE) having very low values of $\Theta$'s and high values of liquid retention. Water wetting properties are greatly improved by adding nonionic surfactants into the system. Generally, hydrophilic surfactants which have low number of carbon atoms or unsaturated hydrophobic structures are effective in improving water wetting of wool fabrics. The water retention of EMPA 217 and 107 in surfactant solutions have positive relations with $cos{\Theta}$, adhesion tension, and work of adhesion. 40.3% pore volume of EMPA 217 and 26.1% pore volume of EMPA 217 can be filled with water even when we assume $cos{\Theta}=1$ (${\Theta}=0^{\circ}$).

• Textile Coloration and Finishing
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• v.23 no.2
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• pp.140-145
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• 2011

The effects of nonionic surfactant solutions of 0.1g/dL on detergency and liquid wetting/retention properties of soiled polyester/cotton(65/35) cloth were studied. Soiled polyester/cotton(65/35) cloth (EMPA 104) and 10 different nonionic surfactants (Span 20, Tween 20, 40, 60, 80, 21, 61, 81, 65, 85) were used in the study. The water retention and liquid retention capacity values of soiled cloth were decreased compared with those of unsoiled cloth. The wetting and water retention of soiled cloth improved with addition of surfactants, whereas water retention ratio(W/H) values didnot change markedly. Generally surfactants with low surface tension and high HLB (Hydrophile-lipophile balance) were more effective in improving the wetting/retention properties of soiled cloth. Nonionic surfactants having high ethylene oxide contents of 20 moles; i.e., Tween 20, 40, 60 & 80, showed better detergency than low ethylene oxide contents of 4 moles; i.e., Tween 21, 61 & 81. As HLB values of surfactants and $cos{\theta}$ of the soiled cloth increase, the detergency values of soiled cloth increased.

• Journal of Energy Engineering
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• v.24 no.3
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• pp.1-5
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• 2015

This study is to investigate the effect of torrefaction on enzymatic hydrolysis of lignocellulosic biomass for bio-ethanol production. As a pretreatment, the torrefaction of lignocellulosic biomass was conducted in temperature of $250{\sim}350^{\circ}C$ in the absence of oxygen. Tween-80, nonionic surfactant, was tested to enhance saccharification efficiency by coping with hydrophobicity resulted from torrefaction. As a result, the glucose production from enzymatic hydrolysis of biomass pretreated by torrefaction was greater than that obtained from the non-pretreated biomass. Sugar conversion was higher when the biomass was saccharified with addition of tween-80. It was found that torrefaction can be applied as a preptreatment for lignocellulosic biomass and tween-80 is needed to enhance its enzyme saccharification.