• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1105-1114
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• 1996

The characteristic and performance of ${\beta}-PbO_2$ layer electrodeposited on ${\alpha}-PbO_2/IrO_2-TiO_2/Ti$ substrate by adding sodium lauryl sulfate and $TiO_2$ powder in lead nitrate solution were investigated by using XRD, SEM, cyclic voltammograms, and macro-elctrolysis. Results of XRD analysis ascertain that ${\beta}-PbO_2$ layers electrodeposited in the presence of sodium lauryl sulfate and $TiO_2$, powder on ${\alpha}-PbO_2/IrO_2-TiO_2/Ti$ substrate have the same tetragonal structure as pure ${\beta}-PbO_2$ layers. The SEM results show that sodium lauryl sulfate tend to diminish crystal size of the deposited layer. The ${\beta}-PbO_2$ electrode electrodeposited in the presence of sodium lauryl sulfate and $TiO_2$ powder gives significantly improved oxygen overvoltage and durability for anodic oxidation in KOH and $HClO_4$ supporting electrolyte. Electrode performance and durability for the evolution of ozone in perchloric acid solution have been investigated by using ${\beta}-PbO_2$ electrodes electrodeposited on Titanium $madras^{(R)}$. It was ascertained that the $PbO_2$ electrode electrodeposited on ${\alpha}-PbO_2/IrO_2-TiO_2/Ti$ $madras^{(R)}$ by adding sodium lauryl sulfate and $TiO_2$ powder in $HClO_4$ supporting electrolyte had the highest current efficiency and durability.

• International Journal of Concrete Structures and Materials
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• v.4 no.1
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• pp.55-62
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• 2010

The performance evaluation of a sodium lauryl sulfate to qualify as a foaming agent is presented in this paper. When new surfactants are used a systematic study of production parameters on the foam characteristics needs to be undertaken unlike proprietary foaming agents and foam generator for which manufacturer has predefined the parameters. The relative influence of the foam parameters and optimization of factors were carried out through a systematic experiment design. The foam production parameters namely foam generation pressure and dilution ratio of foaming agents are observed to have significant effect on all foam characteristics with the exception of foam output rate on which only foam generation pressure has influence. The foam with good initial foam density need not necessarily be stable foam. The optimum levels of foam production parameters are determined for the surfactant Sodium lauryl sulfate which can be used to produce stable foam for foam concrete production.

• Archives of Pharmacal Research
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• v.28 no.1
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• pp.120-126
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• 2005

The objective of this study was to investigate the effects of sodium lauryl sulfate upon the saturation solubility of carbamazepine, its dissolution kinetics, and $T_{50\%}$ defined as the time required for dissolving $50\%$ of carbamazepine. Water, 0.1N-HCI, and phosphate buffers at pH 4.0 and 6.8 containing 0.1, 0.5, 1, and $2\%$ sodium lauryl sulfate were used as dissolution media. The dissolution study was conducted by using the USP dissolution apparatus II with an agitation rate of 75 rpm. Samples of the dissolution media were taken in 7, 15, 30, 45, 60, 75, and 90 min, and the amounts of carbamazepine were determined spectrophotometrically at 285 nm. All dissolution data were fitted well into a four-parameter exponential equation: $Q\;=\;a(1\;-\;e^{-bxt})\;+\;c(1\;-\;e^{-dxt})$. In this equation Q represented $\%$ carbamazepine dissolved at a time t, and a, b, c, and d were constants. This equation led to the calculation of dissolution rates at various time points and $T_{50\%}$. It was found that the dissolution rate of carbamazepine was directly proportional to the aqueous concentration of sodium lauryl sulfate. In addition, under our experimental conditions $T_{50%}$ values ranged from 37.8 to 4.9 min. It was interesting to note that $T_{50\%}$ declined rapidly as the surfactant concentration increased from 0.1 to $0.5\%$, whereas it declined more slowly at concentrations greater than $1\%$. These results clearly demonstrated that the dissolution rate of carbamazepine and duration of its dissolution test could be tailored by optimizing the amount of sodium lauryl sulfate in a dissolution medium.

• Journal of Korean society of Dental Hygiene
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• v.15 no.4
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• pp.719-725
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• 2015

Objectives: The purpose of this study was to determine the toxic effects of sodium lauryl sulfate(SLS) in human keratinocyte HaCaT cells and mouse fibroblast NIH-3T3 cells. Methods: The effect of sodium lauryl sulfate(SLS) cell viability and proliferation were determined by WST-1 assay and changes shape of nucleus were evaluated by Hoechst staining under fluorescence microscopy. Additionally, observation of cell morphological changes under light microscopy. Results: SLS induced cytotoxicity and a marked apoptosis in both HaCaT and NIH-3T3 cell lines. With the result of the WST-1 assay, SLS induced the cytotoxicity of 0.005% and 0.0075%, 0.01% SLS for 24 h after HaCaT and NIH-3T3 cells in time and dose-dependent manner(p<0.005). SLS inhibited cell growth and caused apoptosis as evidenced by nuclear fragmentation and condensation. Thus, determination of the morphological changes to define apoptosis was visualized using inverted phase contrast microscopy. Conclusions: SLS had toxicity of the human keratinocyte cells and mouse fibroblast cells and this study will provide the basic data for the development of proper SLS concentration in dentifrice.

• Journal of Pharmaceutical Investigation
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• v.22 no.4
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• pp.307-315
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• 1992

Dissolution rate of practically insoluble mefenamic acid was improved by roll mixing with sodium lauryl sulfate (SLS) or polyvinylpyrrolidone (PVP). The dissolution rate of the drug roll mixtures with SLS was superior to that of roll mixtures with PVP. The maximal dissolution rate was found in the roll mixtures system with SLS content of 60%. The dissolution rate of mefenamic acid roll mixtures with SLS content of 60% reached to the maximum value after 10 min of roll mixing. The transport of roll mixtures with SLS across rat jejunum was studied by the perfusion method using everted rat jejunum in vitro. The absorption rate of roll mixtures was superior to that of mefanamic acid.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.10 no.1
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• pp.24-41
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• 1984

Tallow fatty acid consists of mixtures of fatty acids differing in chain length and saturation. In separation of tallow fatty acid, the effects of the type and concentration of detergents and electrolytes were studied. And the changes of acid composition of particular fractions were determined by gas-chromatography. Sodium lauryl sulfate (SLS), sodium lauryl ether sulfate (SLES) and sodium lauryl benzene sulfonate (SLBS) were used as detergents and NaCl, Na2SO4 and MgSO4 were used as electrolytes. At low concentration of detergent, the tallow fatty acid was not fully wetted, and at high concentration, the emulsion was so stable that the tallow fatty acid was not well separated. The addition of proper amount of electrolyte increased the separation efficiency by the decrease of interfacial tension and by the increase of the amount of adsorbed detergent on the surface of solid fatty acid crystals. The optimum range of detergent was 0.4-0.6% (wt.) in SLS, 0.2-0.4% in SLES and 2.0-) .0% in SLBS. And the optimum range of electrolyte was 2.0-2.5% in NaCl, 3.0-4.0% In Na2SO4 and 0.5-1.0% in MgSO4 respectively.

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.405-411
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• 2015

Objectives: The purpose of this study is to evaluate the optimum conditions for oral mucosal irritation testing using the buccal pouch of hamsters. Methods: Test materials were applied to the buccal pouch of seven-week old male Syrian hamsters (SLC, Japan) four times at one-hour intervals and macroscopic changes were examined at 24 hours after final treatment. After sacrifice, the buccal pouches were removed and prepared for histopathological evaluation. In order to set the exposure time, we performed exposure tests of 5, 12, 18 and 23 minutes using sodium lauryl sulfate (SLS) 1% and set the treatment volume from the test results at 2, 3, or 4 ml treatment using SLS 1%, Triton X-100 1% and ethanol. After setting the experimental conditions, seven groups of materials [sodium lauryl sulfate (SLS) (1%), Triton X-100 (1%), hydrogen peroxide (3%), ethanol (100%), chlorhexidine (0.2%, 2%), phosphate buffer saline (PBS)] were assessed. Results: Experimental conditions of material exposure time were fixed as 18 minutes from the exposure tests of 5, 12, 18 or 23 min using sodium lauryl sulfate (SLS) 1%. Treated volume was set as 4 ml per each pouch from the test results of 2, 3, or 4 ml treatments using SLS 1%, Triton X-100 1% and ethanol. The results in terms of irritation degree were in the order of sodium lauryl sulfate (SLS) (1%) > Triton X-100 (1%) ${\fallingdotseq}$ hydrogen peroxide (3%) > ethanol (100%) ${\fallingdotseq}$ chlorhexidine (0.2%, 2%) > phosphate buffer saline (PBS). Conclusion: From this study, suitable conditions for hamster mucosal irritation testing were suggested and this method was verified through materials commonly used on oral mucosal membranes.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.404-409
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• 2008

The core-shell composite particles of inorganic/organic were polymerized by using styrene(St) as a shell monomer and potassium persulfate (KPS) as an initiator. We studied the effect of core-shell structure of silicone dioxide/styrene in the presence of an anionic surfactant sodium lauryl sulfate (SLS) and polyoxyethylene alky lether sulfate (EU-S133D). We found that when $SiO_2$ core/PSt shell polymerization was prepared on the surface $SiO_2$ particle, to minimize the coagulation during the shell polymerization, the optimum conditions were at concentration of $2.56{\times}10^{-2}mole/L$ SLS. The structure of core-shell polymer was confirmed by measuring the thermal decomposition of polymer composite using thermogravimetric analyzer and morphology of core-shell polymer particles by transmission electron microscope (TEM).

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.83-90
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• 2008

The core-shell latex particles were prepared by sequential emulsion polymerization using alkyl methacrylate as a shell monomer and potassium persulfate (KPS) as an initiator. We study the effects of core-shell structure of calcium carbonate/alkyl methacrlyate in the presence of an anionic surfactant sodium lauryl sulfate (SLS) and polyoxyethylene alkyl ether sulfate (EU-S133D)). The structure of core-shell polymer were investigated by measuring to the thermal decomposition of polymer composite using thermogravimetric analyzer and morphology of latex by transmission electron microscope (TEM).

• Journal of Pharmaceutical Investigation
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• v.31 no.2
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• pp.81-87
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• 2001

The purpose of this study was to investigate the effect of additives on the powder characteristics of peonja dry elixir. Peonja dry elixirs were prepared with various amounts of dextrin using a spray-dryer, and their powder characteristics such as flow, cohesion and compressibility were evaluated as an angle of repose, cohesion index and compressibility index, respectively. Their powder characteristics were not significantly different from one another, indicating that the hydrophilic dextrin, a base of dry elixir hardly affected their powder characteristics. Peonja dry elixirs were prepared with 10% dextrin and various amounts of additives such as mannitol (hydrophilic excipient), sodium lauryl sulfate (surfactant), colloidal silica (hydrophobic excipient) and HPMC (polymer), respectively, and their angle of repose, cohesion index and compressibility index were measured. The powder characteristics of peonja dry elixirs prepared with mannitol were not significantly different from one another, indicating that the mannitol scarcely improved the powder characteristics of peonja dry elixirs. The angle of repose and cohesion index of peonja dry elixirs significantly decreased with increasing amount of sodium lauryl sulfate to 0.3% followed by no significant changes in them. The cohesion index of peonja dry elixir significantly decreased with increasing amount of colloidal silica. The angle of repose and cohesion index of peonja dry elixir significantly decreased with increasing amount of HPMC to 0.3% followed by an abrupt increase in them. However, the compressibility index of peonja dry elixir significantly increased with increasing amount of HPMC to 0.3% followed by an abrupt decrease in them. Our results suggested that a small amount of sodium lauryl sulfate, colloidal silica and HPMC improved markedly the powder characteristics of peonja dry elixirs due to forming stronger and less hygroscopic shell of peonja dry elixirs. Among the peonja dry elixirs studied, the peonja dry elixir prepared with 0.3% sodium lauryl sulfate and 0.3% HPMC had the lowest angle of repose of $27^{\circ}$ and cohesion index of 37.8%, and the highest compressibility index of 38.7%, respectively. Thus, sodium lauryl sulfate and HPMC appear to be promising additives for peonja dry elixir, if used in adequate amounts.