• Journal of the Korean Geosynthetics Society
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• v.1 no.1
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• pp.43-51
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• 2002

In this study, free swell index of betonite was examined in several regeants; distilled water, leachate, seawater and 3% NaCl solution. Free swell index values of bontonite to be added Poly(acrlylic acid), PYA(Polyvinyl Alcohol) or SCMC (Sodium Carboxymethyl Cellulose) were evaluated and compared. From this, it was confirmed that hydraulic conductivities of GCL in seawater were examined and the hydraulic conductivities of GCL in seawater were compared to those in distilled water. The average values of free swell indices of bentonite were decreased in order of distilled water>leachate>seawater. It was shown that no significant differences were occurred for free swell index between seawater and 3% NaCl solution. For bentonite to be added PVA, the other reagents except distilled water didn't affect increase of swelling. Swelling properties of bentonite to be added SCMC were improved except 3% NaCl solution.

• Restorative Dentistry and Endodontics
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• v.17 no.1
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• pp.95-103
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• 1992

The purpose of this study was to evaluate the effect of the dentin pretreatment on the marginal leakage of a glassionomer cement. 1n this study, 60 molars with sound and healthy crown portion were used. The dentin surface of these teeth were exposed and polished with 600 grit silicon carbide paper. Square - shaped cavities were prepared on the flattened dentin surfaces and these were divided into 4 groups according to the dentin pretreatment procedures. Group I : Dentin pretreatment with distilled water as a control group. Group II : Dentin pretreatment with 5% sodium hypochlorite solution. Group III : Dentin pretreatment with Ketac conditioner. Group IV : Dentin pretreatment with 40% polyacrylic acid. The degrees of dye penetration in the cavity walls were assessed using a stereoscope at ${\times}40$ magnification according to the maximum dye penetration. The results were analyzed by using Mann - Whitney U test. The results were as follows : 1. All groups showed varying depth of dye penetration. 2. Distilled water group showed the most severe marginal leakage when compared with the other groups(P<0.05). 3. 40% polyacrylic acid group showed the least amount of marginal leakage compared with the other groups (P<0.05). 4. There were significant differences between Goup I(distilled water) and Group IV (40% polyacrylic acid)(P<0.05), but there were no significant differences among Group I(distilled water), Group II(sodium hypochlorite), Group III(Ketac conditioner) (P>0.05).

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.2
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• pp.44-48
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• 2004

A silent type ozone generator using water surface electrode was proposed. And it was investigated experimentally that a variation of water conductivity affected to water surface discharge. Important factors affecting to water surface discharge are ions in discharge space and ions and polarized molecules in water and so on. In this study, It was intended to change the characteristics of discharge by controlling the number of ions in water. The number of ions in water could be controlled by changing the water conductivity. Water conductivity was controlled by quantity of inserted NaCl to distilled water. At this time, current-voltage characteristics and characteristics of ozone generation quantity were investigated in each case. As a result, when NaCl was inserted in distilled water, more stable discharge was generated. As the quantity of NaCl was increased, discharge starting voltage could be lowered.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.2
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• pp.269-277
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• 2018

This study extracted Artemisia capillaris Thunberg with distilled water and ethanol to investigate its antioxidant effect. We then investigated the possibility of producing nanofibers by an electrospinning process by adding the extracts to polyvinyl alcohol (PVA). The electrospinning method used a PVA concentration of 12wt.%, an applied voltage of 10kV, and a tip-to-collector distance of 15cm. Total polyphenol and total flavonoid contents were measured to verify the antioxidant activity of Artemisia capillaris Thunberg extracts (ACEs). The total polyphenol content of the distilled water extract and the ethanol extract were measured as 218.47 and 271.26mg/g, respectively, and the total flavonoid content of the distilled water extract and the ethanol extract were measured as 141.68 and 34.98mg/g, respectively. As the content of the ACEs in the PVA nanofibers increased, the Diameters of the nanofibers and the uniformity of the diameters decreased. The electrospinning process was fabricated in a relatively uniform form without beads, and the diameters of the nanofibers that were produced ranged from 340 to 390nm. The results of FT-IR, XRD and DSC analyses confirmed that the ACEs were well mixed with the PVA molecules and were electrospun.

• Biomedical Science Letters
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• v.23 no.4
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• pp.388-394
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• 2017

Recently, coffee is the most popular beverage for modern people. A great number of substances are found in coffee beans and have been studied for many years such as aliphatic and aromatic compounds. However, studies on the physiological activity of coffee extracts are insufficient. This study was performed to determine the contents of caffeine and chlorogenic acid in coffee extracts according to the solvent and to investigate the physiological activity of coffee extracts. Coffee extracts were extracted by ultrasonication method with various types of solvents including distilled water, ethanol, and other organic solvents under $50^{\circ}C$ and $80^{\circ}C$. The contents of caffeine and chlorogenic acid in coffee extracts were determined by Liquid Chromatography-Mass Spectrometry (LC-MS). Also, cytotoxic and antioxidative effects of coffee extracts were evaluated with MTT and DPPH assays to analyze the physiological activity. As a result, it was confirmed that caffeine and chlorogenic acid contents were extracted in distilled water with the highest rate. Antioxidative activity was observed below 10-fold dilute of coffee extracts, however cytotoxicity was not observed. In conclusion, distilled water was the best solvent for extracting caffeine and chlorogenic acids from coffee bean with ultrasonication and these coffee extracts are less cytotoxic in human skin cell lines and have antioxidant effect.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.171-176
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• 2004

Electro chemical corrosion tests were conducted on two structural steels, SS400 and SM490A, in various solutions with different pH values, All materials showed typical active corrosion behaviors in the solutions, and corrosion potential and current density were measured from the slopes obtained from the Tafel curves using linear polarization method. Corrosion potential increased in the acidic region and then decreased depending on the pH values of the solutions. All materials showed the fast corrosion rate in artificial acid rain(pH=4.7), but the slower corrosion rate was observed in NaOH solution(pH=12.0) for SS400 and in distilled water(pH=7.0) for SM490A, respectively, which is thought to come from the difference in chemical composition of two alloys. Generally homogeneous corrosion occurred in acid rain condition, and almost no corrosion was observed in distilled water in both alloys. NaOH solution produced more corrosion than distilled water, and more corrosion had progressed in SS400 than in SM490A in $3.5\%$ NaCl solution.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.732-737
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• 2000

The purpose of this study is to compare the SMD(Sauter mean diameter) with different vibrant plates. Each vibrant plates have different surface roughness. Also liquid film thickness are measured for explanation how to concern atomization. Ultrasonic waves is used for vibration. Immersion liquid method is used for the measure of SMD and also liquid film thickness is measured using of point needle method. Distilled water and gasoline fuel are used to liquids. Supplied liquid flow rates are $18{\sim}296cc/min$. Centerline average roughness of vibrant plates are 0.5, 2.0, 4.7, $9.5\;{\mu}m$ and diameter of vibrant plate is 60mm. In result, good atomization of liquid is obtained in widen flow rates. The mean droplet size is increased in orders of 4.7, 2.0. 9.5, $0.5\;{\mu}m$ surface roughness. Distilled water has a big mean droplet size than gasoline fuel in low flow rate. Above the 78cc/min flow rates, distilled water has a small mean droplet size than gasoline fuel. Liquid films changes are measured with ultrasonic power. Also, cavitation effect on sprays is observed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.7 s.178
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• pp.1841-1846
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• 2000

To examine the effect of acid fog on the corrosion fatigue behavior in structural steel, fatigue tests under acid fog atmosphere were carried out in comparison with distilled water. The corrosive c omponents contained in acid fog pile up the corrosion products on crack face and show a crack branching and crack tip blunting. Therefore, due to these workings crack growth rate was reduced by decreasing the effective stress range in crack tip rather than under distilled water. Also the effect of sulfuric acid, which is the main component of acid fog, and testing speed on fatigue crack growth were examined. It was found that corrosion behavior was remarkably dependent upon pH and Hz rather than components of acid fog. According as pH and testing speed decrease below a specific value, crack growth was accelerated in comparison with distilled water. This reveals that due to liquid having strong acidity and slow speed of test the crack face dissolution was promoted, so crack closure was disturbed in the process of stress descent.

• Korean Journal of Pharmacognosy
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• v.47 no.1
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• pp.18-23
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• 2016

This study was conducted to investigate the tyrosinase inhibitory and melanin production inhibitory activity of the distilled water extract of Dendropanax morbifera leaf (DMW) and the fermented extract by Lactobacillus plantarum (DMF). DMF was prepared by inoculation of L. plantarum after the extraction procedure with distilled water. Fermentation for 48 hours at $37^{\circ}C$ is the most effective condition in this study. In DPPH radical scavenging ability, $SC_{50}$ values of the fermented DMF was $37.9{\mu}g/ml$ as a result of more effective than DMW extract ($52.6{\mu}g/ml$). Moreover, tyrosinase inhibitory activity of DMF showed higher activity than DMW. In nontoxic concentration range, DMF showed strong melanin production inhibitory effect in ${\alpha}$-melanocyte stimulating hormone-stimulated B16F10 cell. As a result, the fermentation of the distilled water extract of D. morbifera leaf by L. plantarum could be applicable to functional materials production for skin-whitening agents.

• Textile Coloration and Finishing
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• v.25 no.4
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• pp.327-336
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• 2013

The purpose of this study was to evaluate the color image of the natural-dyed silk fabrics. The dye was extracted from pine needle by boiling pine needle with ethanol at $78^{\circ}C$ for 3hours and distilled water at $100^{\circ}C$ for 2hours. The 100% silk fabric was dyed of extract in pH 5 at $90-100^{\circ}C$ for 1 hr. As mordants used were compounds of Al, Sn, Fe, and Cr, color image of pine-needle dyed silk fabrics was classified into 5 factors (pure, gentle, sophisticate, comfortable, pastorale) and the factor pure is most important one of those. Most cheerful image in pure factor was from the fabrics dyed with ethanol extract and then, none and Cr mordanting. Dignified image was from the fabrics dyed with ethanol extract and then, Cu or Fe mordanting. In production, products dyed with ethanol extracts was preferred to those dyed with distilled water extracts. Color image and preference of the silk fabrics dyed with pine needles extracted was affected by extraction solvents and mordants.