• Textile Coloration and Finishing
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• v.6 no.2
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• pp.10-16
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• 1994

Neutral salts have negative or positive effects on the rates of many chemical reactions and also on the rates of acidic and alkaline hydrolysis of carboxylic esters. The direction of neutral salt effects on the hydrolysis of ester depends on the charge of esters. Neutral salts accelerate alkaline hydrolysis of esters with negative charge, but decelerate alkaline hydrolysis of esters with positive charge, and have little effect on the alkaline hydrolysis of neutral esters. It is expected that the rate of the alkaline hydrolysis of Poly(ethylene terephthalte) (PET), polymeric solid carboxylic polyester with carboxyl end group at the polymer end, is also influenced positively by neutral salts. In the present work, to clarify the mechanism of the neutral salt effect on the alkaline hydrolysis of PET, many salts with different anions like NaF, NACl, NaBr, NaI were added to the aqueous alkaline solutions. Then PET was hydrolyzed with aqueous solutions of many salts in alkali metal hydroxides under various conditions. Some conclusions obtained from the experimental results were summarized as follows. The reaction rate of the alkaline hydrolysis of PET was increased by the addition of neutral salts and In k was increased nearly linearly with the square root of ionic strength of reaction medium. This fact suggested that the ionic strength effect by Debye-Huckel and Bronsted theory was exerted on the reaction. The specific salt effect was also observed. The reaction rate was increased with the decrease in the nucleophilicity of anions of neutral salts, i.e., in the order of $F^-$ <$Cl^-$<$Br^-$<$I^-$. It was thought that the reaction rate was increased in the order of $F^-$ <$Cl^-$<$Br^-$<$I^-$. because the completion of anions with $OH^-$ for carbonyl carbon became weaker with the decrease in the nucleophilicity and with the increase in the size of anions.

• Journal of Korean society of Dental Hygiene
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• v.1 no.1
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• pp.77-87
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• 2001

The authors have studied the 8 weeks clinical experiment on 34 dental patients of age 20s for control group and 32 for experimental 1 group(Paste Type Dentifrice with Bamboo Salt, Chitosan and Powder of Pine Needles and Leaves of Bamboo.) and 32 for experimental 2 group(Powder Type Dentifrice with Bamboo Salt, Chitosan and Powder of Pine Needles and Leaves of Bamboo), in order to find out the effect of plaque removal, prevention of calculus and stain formation. and Gingival effect. The obtained results are as following. 1. Plaque removal effect was the similar level on group 1 and on group 2 as control group. 2. For prevention of calculus formation, there was a little bit better on group 1 at 8 weeks, and for prevention of stain formation, it revealed more or less difference between on group 1, group 2 and control group at 8 weeks. 3. on PMA index, it revealed the significantly differences between group 1, group 2 and the control group at 8 weeks(p<0.05), so it is estimated that there might be signified for gingival subside effect by use of dentifrice with Bamboo Salt, Chitosan and Powder of Pine Needles and Leaves Bamboo.

• Proceedings of the Korean Society of Crop Science Conference
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• 1994.06a
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• pp.78-79
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• 1994

• Journal of the Korean Chemical Society
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• v.40 no.2
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• pp.148-151
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• 1996

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2329-2330
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• 2008

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.479-485
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• 2009

In this study, basic physical properties were measured for ASCO EQ85 cationic surfactant of triethanolamine-ester quaternary ammonium salt and effect of pH on softening performance on fabrics was investigated using zeta potential measurement and adsorption experiment by quartz crystal microbalance. The CMC of the surfactant was near $3{\times}10^{-3}mol/L$ and the surface tension at CMC was about 40 mN/m. The interfacial tension measurement between 1 wt% aqueous solution and n-dodecane measured by spinning drop tensiometer showed that interfacial tension slightly increased with an increase in pH but the equilibration time was not affected by pH. The surfactant adsorption was found to increase with an increase in surfactant concentration and was also affected by pH of surfactant solution. The friction factor for fabrics treated with ASCO EQ85 surfactant was shown to increase with pH and better softening effect was found under acidic conditions. Half-life for foams generated with ASCO EQ85 surfactant solution increased with pH, which indicated an increase in foam stability with pH.

• Food Science and Preservation
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• v.18 no.2
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• pp.256-265
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• 2011

To investigate the effect of a solar salt on Kimchi fermentation, Chinese cabbages were brined with four-years aged solar salt (FS), one-year aged solar salt (OS), and purified salt (PS). The Kimchi was fermented at $7^{\circ}C$ for 33 days. The changes in pH and acidity of the Kimch brined with PS was slower than those of Kimchis brined with FS and OS. In the Kimchis with FS and OS, lactic acid bacteria (LAB) counts increased from 7.10~7.22 log CFU/mL at 0 day to 9.26~9.42 log CFU/mL at 12 days, after which counts slightly decreased to 8.04~8.75 log CFU/mL by 33 days of fermentation. The LAB counts of the kimchi with PS slowly increased from 7.24 log CFU/mL at 0 day to 8.99 log CFU/mL at 27 days, after then which counts sharply decreased to 7.92 log CFU/mL by 33 days of fermentation. Yellowness (b) color values of the kimchi with PS (59.10) was higher than the Kimchi with FS (53.68) and the Kimchi with OS (53.77). Hardness of the Kimchi with FS was more firm than the other Kimchis after 33 days storage. Sensory evaluation of the Kimchi with FS showed higher score than that of the other Kimchis.

• Journal of the Korean Ceramic Society
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• v.27 no.1
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• pp.62-66
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• 1990

La-modified PbTiO3 Powders and ceramics were prepared by coprecipitation and salt decomposition method. In this process, fine and homogeneous single phase of La-modified PbTiO3 was synthesized at lower temperature than oxide mixing method. And these powders contributed to lowering calcination temperature and rising sintering properties. The properties of these powders and the change of properties with themperature and the effect of powder properties on sintering were investigated.

• Journal of Korean Port Research
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• v.15 no.1
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• pp.99-105
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• 2001

An on-line refractrometer made of easily obtainable materials is built to determine the salinity and temperature of sea water, and its performance is examined by applying the refractometer to known salt solution. Since refractive index and temperature are measured simultaneously, it is possible to compensate the effect of temperature for accurate measurement. The outcome of salinity measurement for the different concentrations of salt solution indicates that the device is suitable for the salinity measurement by yielding stable and reproducible reading.

• Bulletin of the Korean Chemical Society
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• v.8 no.2
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• pp.118-122
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• 1987

The micelle formation of NaDC was studied by fluorometric and viscometric measurements. The thermodynamic parameters of the primary and secondary micellization of the bile salt were evaluated. The primary micelle formation was appeared to be an entropy driven process due to hydrophobic effect, while the major driving force for secondary micelle formation of the bile salt is the large negative enthalpy. The secondary micelle provides less hydrophobic environment to pyrene than the primary micelle does. The cooperative aggregation of primary micelles via hvdrogen bond formation was proposed for the secondary micelle formation.