• Journal of the Korean Society of Clothing and Textiles
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• v.1 no.1
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• pp.31-37
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• 1977

The effects of surfactants and concentration of NaOH in surfactant solution on the removal of free fatty acid soil from cotton fabrics were investigated. Cotton fabrics were soiled with palm itic acid which is the most common fatty acid found in natural oily soil and washed in Lauder-ometer with various types of surfactant with or without NaOH. The rate of soil removal was estimated by analyzing palmitic acid contents in fabric before ar d after washing. Analysis of palmitic contents was made by extracting palmitic acid with azeotropic mixture of alcohol-benzene and the extracts were titrated with standard NaOH solution. It was shown that the types of surfactant are important factor in free fatty acid removal and the efficiency increases in the following order: SLS$90\%$ of initial sorption. In relation to the mechanism of detergency, the suspending and emulsifying power of surfactants were also examined. From the results of this experiments, it could be concluded that the soap formation with alkali and the suspending power of surfactant arc significant factors in free fatty acid soil removal, but the emulsifying power of it is neglizible.

• Food Science and Preservation
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• v.13 no.3
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• pp.389-396
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• 2006

In order to prepare liqueur of citrus fruit, changes of major constituents, flavonoid pH, color changes, and extract, by soaking 3 kg/6 L kumquats for $1{\sim}70$ days and 1 kg/3 L Citrus platymama for $1{\sim}50$ days in $30{\sim}95%$ ethanol solution were investigated 1.5kg of kumquats, and 1kg of citrus platymama were soaked in 3 L of $30{\sim}95%$ ethanol solution for $50{\sim}70$ days. pH and color changed largely by ethanol concentration. Glucose and fructose were more extracted in $60{\sim}95%$ ethanol concentration. Citric acid and malic acid were extracted $10{\sim}15$ times with kumquats than with Citrus platymama in 30% ethanol solution. Ascorbic acid was more extracted in 60% ethanol solution for kumquats, and in 95% ethanol for Citrus platymamma. The content of ascorbic acid was $3.19{\sim}41.91{\mu}g/mL$ in kumquats, and $21.90{\sim}30.12{\mu}g/mL$ in Citrus platymamma. $312.82{\sim}688.12{\mu}g/mL$ of rutin were extracted in 95% ethanol solution, $9.32{\sim}74.49{\mu}g/mL$ of neohesperidin were extracted in 60% ethanol as for kumquats. Rutin and neohesperidin were more extracted in 30% ethanol concentration contrary to hesperidin. Hesperidin was extracted $38.93{\sim}136.86{\mu}g/mL$ in 95% ethanol solution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.587-593
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• 2009

This study was carried out to investigate the quality characteristics of ginseng Jung Kwa and Jung Kwa solution prepared according to boiling frequency on Jung Kwa process. Ginseng Jung Kwa was made as follows: washed ginseng 8 kg was boiled 5 min with water 16 kg and then boiling water 8 kg was removed. Sucrose 10 kg was added to boiled ginseng soaking in hot water. Jung Kwa was boiled down for 60 min in sugar syrup and soaked for 24 hrs. According to the above process, Jung Kwa was boiled down 5 times. Moisture and pH of Jung Kwa and Jung Kwa solution decreased as the number of boiling time increased and $^{\circ}Brix$ of Jung Kwa solution increased. Crude saponin content of last Jung Kwa (GJ 6) increased to 4 times of raw ginseng. Content of Rf and Rd, component of ginsenosides, increased 77 and 16 times on Jung Kwa, respectively and content of crude saponin on last Jung Kwa solution (GJS 5) was 61.88 mg/g. The other ginsenosides on Jung Kwa decreased. As the number of boiling time increased, concentration of total sugar, glucose and fructose of Jung Kwa and Jung Kwa solution increased. Content of total organic acid on Jung Kwa decreased, especially, succinic acid, main organic acid of ginseng, decreased rapidly. L value of Jung Kwa decreased whereas a and b values increased.

• Applied Chemistry for Engineering
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• v.30 no.3
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• pp.358-364
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• 2019

To improve the optical characteristics and antifouling of anti-reflective coating (AR) films, various AR coating films were prepared by varying the mixing ratio of tetraethylorthosilicate (TEOS)/base and methyltrimethoxysilane (MTMS)/acid hybrid solution. Prepared AR coating films were characterized by UV-Vis spectroscopy, contact angle analyzer, atomic force microscope (AFM), FT-IR and pencil scratch hardness test. In an AR coating film that prepared from the hybrid solution with a 10 wt% MTMS/acid solution, the glass substrate showed an excellent optical property (97.2% transmittance), good antifouling ($121^{\circ}$ water contact angle and $90^{\circ}\;CH_2I_2$ contact angle) and moderate mechanical strength (pencil hardness of 4 H). In particular, it is considered that the good antifouling was due to the well dispersion of the methyl group ($-CH_3$), derived from a small amount of MTMS/acid solution in the hybrid solution, on the substrate surface. From results of the pencil hardness test, the mechanical strength of AR coating film was improved as the content of MTMS/acid solution increased.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.2
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• pp.356-365
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• 1995

study was made to investigate the emulsification and rolling-up between liquid oily soils and surfactant and its effect on the detergency. Samples used were triolein as a triglyceride, oleic acid as a free fatty acid and sodium dodecyl sUJfate(SDS) as a surfactant. The results were as follows: 1. The spontaneous emulsification occurred in the system of oleic acid alone and mixture of triolein and oleic acid contacted with 0.5% SDS solution, but it did not occurred in a case of triolein alone. 2. The stability of emulsification increased with the increase of SDS concentration. And the stability of emulsification and (-) t value increased in the order of triolein < mixture of triolein and oleic and< oleic acid. 3. The rolling-up mechanism of model oily soils easily occurred in the order of triolein< mixture of triolein and oleic acid< oleic acid, and facilitated with the increase of SDS concentration. On the other hand, the complex formation was already observed in the system of oleic and 0.5% SDS solution. 4. As compared with the detergency of triolein, the detergency of oleic acid was very high. And the detergency of mixed soil was improved with increasing ratio of oleic acid in the mixture.

• Journal of the Korean Home Economics Association
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• v.32 no.5
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• pp.143-152
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• 1994

To investigate the changes of taste perception by aging, sixty one healthy elderly people and sixty five young adults were participated in the study. Most preferred levels of salt sour and sweet taste were chosen in bean sprout soup radish salad and yaksing respectively. Threshold levels of each taste were also chosen in NaCl solution for salt taste in citric acid solution for sour taste and in sucrose solution for salt taste, in citric acid solution for sour taste and in sucrose solution for sweet taste. The results are as follow: 1.Most preferred salt concentration in bean sprout soup was significantly higher in the elderly than in the young adults(p$\leq$0.001). There was no difference in sour taste preference of radish salad in both age groups. Most preferred sweetness in yacksig was significantly higher in both elderly men and women(p$\leq$0.001) 2. Threshold levels of salt and sweet taste were significantly higher in the elderly (p$\leq$0.001) However there was no difference in threshold level of sour taste in both age groups.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.978-980
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• 2010

This study was conducted to observe the cause of injury of fig plant. Nitrogen dioxide gas can be evolved at low pH or reduced in soil. Fig plant cultivated with nutrient solution was wilted or withered. Injury symptom for nutrient solution containing nitrous acid was worse as pH of soil decreased. However, increase in pH of nutrient solution treated with increasing $Ca(OH)_2$ solution prevented nutrient solution from producing nitrogen dioxide gas. Recovery of the fig plant by pH increase indicated that the cause of injury was nitrogen dioxide gas.

• Journal of the Korean Society of Food Culture
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• v.9 no.4
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• pp.411-417
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• 1994

The extraction condition and quality attributes components in Oolong tea were investigated. Extraction yield was high in $80{\sim}85^{\circ}C$ above 50% ethanol solution. Sucrose content most high among the free sugar ranged $37.2{\sim}55.0\;mg/100\;g$, while arabinose was the least. Organic acids in ethanolic extracts were furmaric, citric and malic acid. Free amino acids were 15 kinds and contents of proline, tyrosine and glutamic acid were comparatively high. Tannin content extracted from water and 25% ethanol solution were 38.6 and $38.5\;{\mu}g/100\;g$, it decreased as ethanol concentration increase. Caffeine content did not changed as extraction conditions. Ascorbic acid content was $6.5\;{\mu}g/g$ when extracted from 25% ethanol solution, it decreased as ethanol concentration increase. Bitter and astringent taste affected to overall preference of Oolong tea. Tea manufactured from 25% ethanol solution extracts recorded most high organoleptic score than any other extraction condition.

• Journal of Environmental Science International
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• v.12 no.4
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• pp.469-476
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• 2003

In order to examine the pre-treatment effect of crab shell en Pb$^{2+}$ removal by crab shell in aqueous solution, acid and alkali pre-treated crab shell were used. Electron microscopy techniques such as TEM (transmission electron microscopy) and SEM (scanning electron microscopy), and EDX (energy dispersive X-ray) and FTIR (Fourier transform infrared) spectrometry techniques were used to investigate the process of Pb$^{2+}$ removal by acid and alkali pre-treated crab shell. The Pb$^{2+}$ removal by acid pre-treated crab shell was much lower than that by untreated crab shell because of the decrease of CaCO$_3$ from the crab shell. However, the Pb$^{2+}$removal by alkali pre-treated crab shell increased compared to that by untreated crab shell. The results were confirmed by TEM, SEM, EDX and FTIR.nd FTIR.

• Journal of the Korean Chemical Society
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• v.12 no.4
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• pp.155-159
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• 1968

On the extraction of humic acid from peat, the optimum conditions were studied and the effects of them on the characteristics of humic acid were also examined by means of infrared spectroscopy. 1. Pretreatment of peat with diluted 6-8% HCl solution for 5 hrs. prior to extraction with alcohol-benzol azeotropic mixture have resulted the better yield of humic acid. The water soluble Na-humates were obtained by the subsequent extraction with one hundred times quantity of caustic soda solutieon for 1hr. at 90 $^{\circ}C$. Thus the pure humic acids have been yielded approximately 40% (by wt.) from the raw peat. 2. In characteristics of humic acid, the chemical structure, mainly the contents of such functional groups as -COOH, -OH (phenol type), $-CH_2CO-$, $-CH_2{\cdot}O{\cdot}CH_2-$ and aromatic rings were varied according to the concentration of alkaline solution, temperature and time when the humic acids were extracted with alkali.