• Proceedings of the KSME Conference
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• 2000.04b
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• pp.328-334
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• 2000

This research was concerned with the enhancement of heat transfer by surfactant added to the aqueous solution of LiBr. Different horizontal tubes were tested with and without an additive of normal octyl alcohol. The test tubes were a bare tube, floral tube, hydrophilic tube. The additive concentration was about $0.05{\sim}5.5mass%$. The heat transfer coefficient was measured as a function of solution flow rate in the range of $0.01{\sim}0.034 kg/ms$. The experimental result were compared with cases without surfactant. The enhancement of heat transfer by Marangoni convection effect which was generated by addition of the surfactant is observed in each test tube.

• YAKHAK HOEJI
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• v.11 no.3_4
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• pp.17-21
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• 1967

At present, quarternary ammonium salts(cationic surfactant) and Tego compounds (amphoteric surfactant) are used as germicidal agent. In this paper, it was investigated whether their germicidal activities are influenced or not by some suspending agents which are added to them 0.005% benzalkonium chloride aq. solution and 0.05% dodecyl diaminoethyl glycine aq. solution sterilized respectively against Staphylococcus aureus and Escherichia coli within a minute. The solutions aded acacia, carboxymethyl cellulose, sodium alginate solutions to make to 0.005% to above surfactants solution decreased the germicidal activity, not being sterilized bacteria for more than 2 hours however, the solutions decreased the germicidal activity by addition of suspending agents such as acacia, carboxymethyl cellose, sodium alginate and bacteria were survival for more than 2 hrs, 0.05% of benzalkonium chloride and 0.1% dodecyl diaminoethyl glycine respectively would be sterilized within 10 minutes, when added to 5% suspending agents. This result show that bactericidal action of dodecyl diaminoethyl glycine is affected by suspending agents less than that of benzalkonium chloride.

• Korean Journal of Materials Research
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• v.16 no.2
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• pp.75-79
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• 2006

The effect of ozone and/or ultrasound treatments on the efficiency of slurry removal in post sliced cleaning (PSC) of silicon ingot was studied. Efficiency of slurry removal was evaluated as functions of time, temperature and surfactant with DOE (Design of Experiment) method. Residual slurries were observed on the wafer surface in case of cleaning by ozone or ultrasound separately. However, a clean wafer surface was appeared when cleaned with ozone and ultrasound simultaneously. It has found that cleaning time was the main effect among temperature, time and surfactant. Elevated temperature, addition of surfactant and high ozone concentration helped to accelerate efficient removal of slurry. The improvement of removal efficiency seems to be related to the formation of more active OH radicals. The highly cleaned surface was achieved at 10 wt% ozone, 1 min and 10 vol% surfactant with ultrasound. Application of ozone and ultrasound might be a useful method for PSC process in wafer cleaning.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.463-471
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• 1994

Physicochemical properties, gelatinization and retrogradation characteristics of surfactant added sweet potato starches were investigated. Three different surfactants, SSL (sodium stearoyl-2-lactylate), Dimodan (mono/diglyceride) and SE1670 (sucrose fatty acid ester 1670) were used. Shapes and crystallinities of starch granules were not changed by the addition of surfactants. Total lipid contents increased and the amylose content decreased by the addition of surfactants and the order was as follows: SE1670>SSL>Dimodan. The swelling power and solubility at $80^{\circ}C$ decreased in the surfactant added starches. By amylograph, initial gelatinization temperature of untreated sweet potato starch was $72.5^{\circ}C$, and did not change by the addition of surfactants, but SE1670 or Dimodan added starch showed the peak viscosity. The peak temperature of gelatinization and enthalpy of untreated starch by DSC were $53.9^{\circ}C$ and 1.3cal/g, respectively. The peak temperature increased by the addition of surfactants, while the enthalpy decreased. In gelatinization by alkali, the viscosity was lower in surfactant added starches than in untreated starch at concentration. The degree of retrogradation by ${\alpha}-amylase-iodine$ method was a lower in SSL and SE1670 added starches than untreated starch and the enthalpy by DSC also decreased in surfactant added and retrograded starches.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1151-1157
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• 2003

The surfactant Tween 80 was evaluated for its ability to influence cumulative gas production, cellulose digestion, and enzyme activities by mixed ruminal microorganisms grown on barley grain or Orchardgrass hay. The addition of Tween 80 at a level of 0.10% significantly (p<0.05) decreased the cumulative gas production rate from both barley grain or Orchardgrass hay substrates. However, 0.05% Tween 80 did not affect gas production rates compared to the control treatment. The addition of 0.05% Tween 80 to cultures growing on barley grain resulted in a significant increase in cellulase (90.01%), xylanase (90.73%) and amylase (487.25%) activities after 30 h incubation. Cultures utilizing Orchardgrass hay had a significant increase in cellulase (124.43%), xylanase (108.86%) and amylase (271.22%) activities after 72 h incubation. These increases in activities were also observed with cultures supplemented with 0.10% Tween 80 throughout all the incubation times tested. These results indicated that the addition of 0.05% Tween 80 could greatly stimulate the release of some of key enzymes without decreasing cell growth rate in contrast to trends reported with aerobic microorganism. Our data indicates potential uses of the surfactant Tween 80 as a feed additive for ruminant animals.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.308-311
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• 2003

The mesoporous TiO2 film for the dye-sensitized solar cell was prepared by the spin coating using nano particle $TiO_2$ slurry. In order to obtain the good dispersion of nano size $TiO_2$ particles in slurry, the pH of solvent, the sort and quantity of solvent additive and the quantity of surfactant were adjusted. The experimental range of pH was $2\;{\sim}\;4$. The basic solvent for slurry was dilute $HNO_3$ and the solvent additives were ethylene glycol, propylene glycol and butylene glycol. The degree of particle dispersion was indirectly estimated by the viscosity of slurry and the microstructure after sintering. As results, the lower the pH of solvent was the lower the viscosity of the slurry became. The addition of ethylene glycol and propylene glycol to dilute $HNO_3$ brought about the lowering of viscosity and the enhancement of stability in slurry. The addition of surfactant lowered the viscosity of slurry. It was possible to obtain the homogeneous and uniformly dispersed mesoporous TiO2 film using the dilute HNO3 solvent of pH 2 with the addition of ethylene glycol, propylene glycol and neutral surfactant.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.1001-1005
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• 2004

Rye-sensitized solar cell (DSSC) is a new class of solar cell, which consists of nanoporous TiO$_2$ electrode, dye-sensitizer, electrolyte, and counter electrode. Such cell is operated in sunlight via the principle of photosynthetic electrochemistry. In order to obtain the good dispersion of nano size TiO$_2$ particles In slurry, the pH of solvent, the sort and quantify of solvent additive and the quantity of surfactant were adjusted. As results, the lower the pH of solvent was the lower the viscosity of the slurry became. The addition of ethylene glycol and propylene glycol to dilute HNO$_3$ brought about the lowering of viscosity and the enhancement of stability in slurry. The addition of surfactant lowered the viscosity of slurry. It was possible to obtain the homogeneous and uniformly dispersed mesoporous TiO$_2$ film using the dilute HNO$_3$ solvent of pH 2 with the addition of ethylene glycol and neutral surfactant. DSSC was assembled with TiO$_2$ electrode and Pt electrode, and its photoelectric property was measured using the monochromatic wavelength in the rangee of 350∼700 nm.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.11
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• pp.867-873
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• 2006

Vertical falling liquid film is extensively used in heat and mass transfer processes of many applications, such as evaporative coolers, cooling towers, and absorption chillers. In such cases, it is required that the falling film spreads widely in the surface forming thin liquid film to enlarge contact surface. An addition of surface active agent to a falling liquid film or hydrophilic surface treatment affects the fluid physical properties of the film. Surfactant addition not only decreases contact angle between the liquid and solid surface but also changes the surface from hydrophobicity to hydrophilicity. In this study, the effects of contact angle on falling film characteristics over a vertical surface have been investigated experimentally. The contact angle is varied either by an addition of surfactant to the liquid or by hydrophilic surface treatment. It is found that the wetted area is increased and film thickness is decreased by the hydrophilic treatment as compared with those of other surfaces. With this hydrophilic treatment, the falling liquid film spreads out widely in the surface. As surfactant concentration is increased, wetted area is also increased and the film thickness is substantially decreased.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.3 s.31
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• pp.286-294
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• 1989

This Study has treated the effects of fiber, surfactants, temperature, surfactant concentration, pH, electrolyte, fatty acid contents and mechanical force on the removal of particulate soil from fabric, vacuum cleaner dirt was used as model particulate soil. The fabrics were soiled with mixture of vacuum cleaner dirt and fatty soil, and washed in Terg-O-tometer. The detergency was evaluated by measuring reflectance of a fabric before and after washing. The results were as follows. 1. The fiber type showed a different pattern of soil removal with surfactants. In general, particulate soil removal increased in the following order Acetate>PET. Nylon>Cotton. Particulate soil removal, which is affected by the surfactant type, increased in the following order NPE $(EO)_{10}\leqq$Soap>SLS>DBS>Tween 80. 2. The influence of temperature on the particulate soil removal was very complex because efficiency of removal was varied with surfactant and fiber types. The washing efficiency of NPE $(EO)_{10}$ was highest at around $40^{\circ}C\;and\;60^{\circ}C$ with cotton and PET but the washing efficiency of DBS was the highest at $60^{\circ}C$ with cotton, decreased monotonously with increasing temperature with PET 3. The detergency of particulate soil increased with increasing surfactant concentration at relatively low concentration and then levelled off above some optimum concentration. 4. The removal of particulate soil increased with increasing pH and mechanical force. 5. Effect of electrolyte on the particulate soil removal was depended on the concentration of the surfactant. At low concentration of surfactant, addition of electrolytes improved soil removal but above the some concentration no effect was observed. At high concentration of surfactant, Vie., $0.6\%$ , the maximum washing effect is reached without added electrolyte. These result indicate that added electrolyte only influence the adsorption of surfactant on the soil and fiber 6. Fatty acid content in the soil did not influence on particulate soil removal without regard to surfactants.

• Elastomers and Composites
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• v.53 no.2
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• pp.39-47
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• 2018

Styrene-butadiene rubber (SBR) is widely used in tire treads due to its excellent abrasion resistance, braking performance, and reasonable cost. Depending on the polymerization method, SBR is classified into solution-polymerized SBR (SSBR) and emulsion-polymerized SBR (ESBR). ESBR is less expensive and environmentally friendlier than SSBR because it uses water as a solvent. A higher molecular weight is also easier to obtain in ESBR, which has advantages in mechanical properties and tire performance. In ESBR polymerization, a surfactant is added to create an emulsion system with a hydrophobic monomer in the water phase. However, some amount of surfactant remains in the ESBR during coagulation, making the polymer chains in micelles clump together. As a result, it is well-known that residual surfactant adversely affects the physical properties of silica-filled ESBR compounds. However, researches about the effect of residual surfactant on the physical properties of ESBR are lacking. Therefore, in this study we compared the effects of remaining surfactant in ESBR on the mechanical properties of silica-filled and carbon black-filled compounds. The crosslinking density and filler-rubber interaction are also analyzed by using the Flory-Rehner theory and Kraus equation. In addition, the effects of surfactant on the mechanical properties and crosslinking density are compared with the effects of TDAE oil (a conventional processing aid).