• Textile Coloration and Finishing
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• v.22 no.3
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• pp.220-228
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• 2010

This study examines the scouring effect of pectinase on ramie fabric and influence of sodium sulfate as an activator for pectinase. The scouring effects were measured by the weight loss and pectin contents. SEM, weight loss, stiffness, moisture regain and dye ability of ramie fabric teated with pectinase/sodium sulfate were also measured. When ramie fabrics were desized with $\alpha$-amylase, the optimum conditions were pH 6.5 at $60^{\circ}C$ for 80 min with 1%(o.w.f) $\alpha$-amylase concentration. When ramie fabrics were scoured with pectinase, the optimum conditions were pH 8.5 at $55^{\circ}C$ for 30 min with 10%(o.w.f) pectinase concentration. Addition of sodium sulfate improved enzyme activity significantly, which increased proportionally with increasing sodium sulfate concentration. When 50 g/l of sodium sulfate was added, the surface became cleaner compared to the enzyme treatment without salt: weight and tensile loss, moisture regain and dyeability of the treated fabrics increased, while pectin contents and stiffness decreased. Therfore, sodium sulfate was effective activator for the pectinase treatment of flax fiber.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.679-684
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• 2017

Hydrated liquid crystalline vesicles incorporating a edge activator, which confers flexibility to the vesicle membranes, were prepared and niacinamide was encapsulated in them. The formation of liquid crystalline phases and their thermal phase transitions were investigated by polarized optical microscopy and differential scanning calorimetry (DSC), respectively. Droplet sizes of the vesicles were reduced to several tens of nanometers by incorporating edge activators, such as sodium deoxycholate, lysolecithin, or polysorbate 80. The amount of niacinamide permeated into a pig skin increased greatly using the hydrated liquid crystalline vesicles compared to the case where niacinamide was applied in an aqueous solution state. The vesicles incorporating 10% sodium deoxycholate increased the amount of niacinamide permeated nearly four times. These results suggest that edge activators are effective in improving the skin permeability of vesicles.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.789-792
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• 2006

The purpose of this study is to investigation the fundamental properties of alkali activated slag of type and concentration of alkali activator. In this paper sodium silicate, sodium carbonate and sodium hydroxide were used as alkaline activator and their concentration were 1, 3, 5 and 7 $Na_2O$ weight percent. The physical properties of alkali activated blast furnace slag cement mortar (AAS) were investigated by flow test and compressive strength. And the hydration properties of AAS characterized by X-ray diffraction and scanning electron microscope. Result show that Alkali activated slag mortar strengths were continuously increased with adding amount and ages. C-S-H were formed to be the main products up to 28days of hydration.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.7
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• pp.1085-1092
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• 2002

Changes in laundering habits and the efficacy claims made for oxygen bleach added to detergents necessitate a deeper investigation into the testing of the washing efficacy of detergents and washing process. The effect of the addition of a sodium percarbonate and bleach activator TAED to an enzyme containing detergent on the soil removal and antimicrobial properties were investigated with the measuring of residual H$_2$O$_2$. The addition of sodium percarbonates to enzyme containing detergent lowered the soil removal of EMPA 116 cloth. But sodium percarbonates had greater effects on that of colored stained cloths such as EMPA 115 and artificially soiled with wine and red pepper while they were presoaked at 20$^{\circ}C$ or higher for So minutes or longer. Most of hydrogen peroxide was remained after washing. Over 99.9% of Staphylococcus aureus on the cotton cloth was removed in every washing solutions, but the cloth washed with enzyme containing detergent or detergent with oxygen bleach didn't show the antimicrobial property.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.9
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• pp.1461-1466
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• 2008

This study provides effects of mixed activators on enzymatic activation and determines optimum mixture ratio for enzymatic treatment. Wool 80% and polyester 20% blend fabric and papain from carica papaya are used in this experiment. L-cysteine and sodium sulfite are used as activators for papain treatment process. The treatment condition is pH 7.5, $70^{\circ}$, papain concentration 10%(o.w.f), 60 minutes. L-cysteine and sodium sulfite are added in enzyme solution with various concentrations($0{\sim}50mM$). The optimum treatment condition is determined by measuring weight loss, tensile strength, whiteness, water contact angle(WCA), dyeability and surface micrographs. The results are as follow; The optimum mixture ratio of activators is L-cysteine 2mM and sodium sulfite 10mM. Mixed activators assists in improving the activation of papain. WCA of papain treated fabrics is decreased since papain treatment with activator mixture makes wool polyester blend fabrics more hydrophilic. Dyeing property of papain-treated fabrics more improves by the treatment with mixed activators than with single activator. It means that this method can save time and lower cost. After papain treatment in the presence of mixed activator, the surface of fabrics is modified. The surface of wool fiber shows to be descaled and hydrolyzed, and that of polyester fiber shows to be cracked.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.503-512
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• 2020

Using Na₂CO₃ versus NaCl as chemical activator, we compared the quality of activated carbon produced from oil palm fronds as raw material. These activators were selected for comparison because both are readily available and are environmentally friendly. In the manufacturing, we used Indonesian National Standard (SNI 06-3730-1995) parameters. For the quality comparison, we determined activated-carbon yield, moisture, ash, volatiles, and fixed-carbon contents; and adsorption capacity of iodine. The best characteristics, assessed by morphological surface analysis and Fourier transform infrared (FTIR) spectral analysis, were observed in the carbon activated by Na₂CO₃ at an activator concentration of 10% and carbonization temperature of 400 ℃. The results were as follows: activated-carbon yield, 84%; water content, 8.80%; ash content, 2.20%; volatiles content, 14.80%; fixed-carbon content, 68.60%; and adsorption capacity of iodine, 888.51 mg/g. Identification using the FTIR spectrophotometer showed the presence of the functional groups O-H, C=O, C=C, C-C, and C-H in the Na₂CO₃-activated carbon.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.137-145
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• 2012

Strength model for blasted furnace slag mortar blended with sodium was investigated in this study. The main parameters of AAS (alkali activated slag) mortar were dosage of alkali activator, water to binder ratio (W/B), and aggregate to binder ratio (A/B). For evaluating the property related to the dosage of alkali activator, sodium carbonate ($Na_2CO_3$) of 4~8% was added to 4% dosage of sodium hydroxide (NaOH). W/B and A/B was varied 0.45~0.60 and 2.05~2.85, respectively. An alkali quality coefficient combining the amounts of main compositions of source materials and sodium oxide ($Na_2O$) in sodium hydroxide and sodium carbonate is proposed to assess the compressive strength of alkali activated mortars. Test results clearly showed that the compressive strength development of alkali-activated mortars were significantly dependent on the proposed alkali quality coefficient. Compressive strength development of AAS mortars were also estimated using the formula specified in the previous study, which was calibrated using the collected database. Predictions from the simplified equations showed good agreements with the test results.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.26-33
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• 2012

This paper reported on the effect of blended activator on the physical properties of alkali-activated slag mortar. Five different activators(caustic alkalis) were used: sodium hydroxide(NaOH, A Case), calsium hydroxide($Ca(OH)_2$, B Case), magnesium hydroxide($Mg(OH)_2$, C Case), aluminum hydroxide($Al(OH)_3$, D Case), and potassium hydroxide(KOH, E Case). We blended five caustic alkalis with sodium carbonate($Na_2CO_3$). The dosage of five caustic alkalis was 3M and sodium carbonate was 1M, 2M and 3M. The result of flow and setting time was decrease as the dosage of sodium carbonate increase. But the compressive strength was increase as the dosage of sodium carbonate increase. It was shown that there is a good effect of blended caustic alkalis with sodium carbonate in alkali-activated slag mortar.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.6
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• pp.661-666
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• 2006

The compressive strength of a paste composed of a low-calcium Class F fly ash and alkaline activator solutions was investigated. These activator solutions, made with sodium hydroxide, water glass and water, have a very high $OH^-$ concentration. The composition of alkaline activator solution and temperature have been shown to notably influence the development of the compressive strength of the fly ash-cements paste. Compressive strength of 50 MPa could be achieved by curing of the fly ash at $60^{\circ}C$ for 48 hrs or $85^{\circ}C$ for 24 hrs. This study presented the optimum mixing ratio of Class F fly ash/sodium hydroxide/water glass as 25:8:2 in weight basis, and activator/fly ash as 0.6/1.0 for high strength paste.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.532-540
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• 2021

Sodium dodecanoyl-4-oxybenzenesulfonate (DOBS) salt is a substance that exhibits effective bleaching and antimicrobial abilities at low temperatures. A mild and efficient synthesis method of DOBS starting from dodecanoyl chloride and sodium 4-hydroxybenzene sulfonate was investigated under alkaline conditions using a water (W)-polar aprotic solvent system. First, the reaction was carried out using only water as a solvent system with the variables of temperature and time. The yield was found to be as low as about 5% in most cases under the reaction conditions of more than 30 ℃ and 1 h. In order to develop an efficient solvent system, the effect on the yield of DOBS was evaluated in various solvent systems which were prepared by changing the type of polar aprotic solvents while mixing them with the water. A solvent system in which acetone (AC) and water were mixed showed the best yield and about 82 % under mild reaction conditions (30 ℃, 1 h and atmospheric pressure) was obtained. The prepared DOBS showed good bleaching and antimicrobial activities indicating that it could be used an excellent bleach activator.