• Title/Summary/Keyword: distilled water

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알루미나 세라믹스의 분위기 변화에 따른 Tribology 특성

  • 진동규;박흥식;전태옥;이광영
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1997.04a
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    • pp.33-40
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    • 1997
  • This study was undertaken to investigate tribology characteristics of the alumina ceramics($Al_2O_3$) for the vauiation of ambient condition such as air and distilled water. The results obtained were as follows. As the sliding speed increases, the friction coefficient in the air decreased due to the reduction of sheafing stress caused by the heat accumulation of contact interface. And the friction coefficient in the distilled water decreased due to an activation of the tribochemical reaction. As the contact load increases, the friction coefficient is small in the air due to temperature rise of the contact interface. However, at the low speed side in the distilled water, the friction coefficient holds a large value due to decrease of the tribochemical reaction. The friction surface of ceramics can be protected in the air by the influence of the oxides tansfered from STB2 and also in the distilled water by the influence of the corrosive productive hydroxides.

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Optimization of Extraction of Fpase from the Fermented Bran of Aspergillus niger in Solid State Fermentation

  • Chandra, M. Subhosh;Reddy, B. Rajasekhar;Choi, Yong-Lark
    • Journal of Applied Biological Chemistry
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    • v.51 no.4
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    • pp.155-159
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    • 2008
  • A local isolate of Aspergillus niger was cultivated under optimal growth conditions on wheat bran in solid state fermentation. Filter paperase from fermented bran was separately extracted with different solvents to test the recovery of the enzyme. Among solvents tested, distilled water served as the best leachate, thus the conditions were further optimized with distilled water. After two washes of fermented bran with distilled water for 1.5 h each under stationary conditions at 1 g wheat bran: 5 mL distilled water, the maximum recovery of 13.5 $Ug^{-1}$ of wheat bran was obtained.

A comparison of destructive behaviors of distilled water, salty water, sulfuric acid and heat on glass/vinyl ester composites

  • Asli, S.A.;Shokrieh, M.M.;Kamangar, M.A.
    • Composite Materials and Engineering
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    • v.3 no.3
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    • pp.167-178
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    • 2021
  • In the present paper, the destructive behavior of distilled water, salty water, sulfuric acid, and heat on glass/vinyl ester composites was investigated by experimental methods. Hetron 922 vinyl ester resin and two types of mat and woven glass fibers as the reinforcements were used to fabricate composite test samples. All samples were immersed in distilled water, salty water, and sulfuric acid with three different concentrations. The tests were performed at 20℃ and 70℃ for the exposure duration of 1, 2, 4, and 8 weeks. Bending tests were performed after aging for all composite samples to check the degradation of the bending modulus and strength. The results show that the effect of distilled water, in comparison with salty water, on the degradation of composite samples was significant. On the other hand, almost non-sensitivity of concentrations of salty water on the weight gain of specimens has been observed. In addition, it was also observed that the degradation of samples at 70℃ temperature is much more than that of at 20℃. Also, it was observed that the flexural modulus of virgin specimens exposed to salty water (2% concentration) has been recovered just after two weeks of immersion. Furthermore, in some cases, composite samples under the sulfuric acid solution have lost almost 80% of their mechanical properties.

Effect of Washing Treatment of Aged Paper Materials for Better Conservation (열화된 종이자료의 보존성 개선을 위한 세척처리 특성)

  • Lee, Kwi-Bok;Seo, Yung-Bum;Park, So-Yeon;Jeon, Yang;Shin, Jong-Soon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.4 s.117
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    • pp.53-60
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    • 2006
  • Paper materials for long term conservation suffer slowly mechanical and chemical deterioration, the extent of which may depend upon their conservation environment. Those deterioration includes discoloring, low moisture content, acidification, and brittleness. To slow deterioration, washing treatment, deacidification, and polymer reinforcement on paper materials are usually used. One easy and simple method of fixing low moisture content and acidification was an washing method, and we used both distilled and alkali water in washing method in this study. Alkali water is electrolyzed cathode water of high pH, and has no alkali metal ions in it. Experiment showed that washing treatment with both distilled and alkali water gave improvement in raising moisture content, pH, and mechanical strength of paper materials even after severe accelerated aging test. Advantageous effect of alkali water over distilled water on preventing deterioation was also shown clearly.

Characteristics and Dyeability of Juniperus Chinensis Extracts (향나무 추출 색소의 특성 및 염색성)

  • Nam, Ki Yeon;Lee, Jung Soon
    • Korean Journal of Human Ecology
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    • v.21 no.5
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    • pp.989-1004
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    • 2012
  • The purpose of this study was to investigate the characteristics of the pigment and the dyeability of juniperus chinensis needles, berry, bark and heartwood extracts using distilled water, methanol, normal butanol and ethyl acetate as a solvent. Ultraviolet-visible absorption spectrum bands of the extracts were measured at around 280nm to 320nm in all the solvent extracts. The maximum absorption wavelength was able to determine tannin. All the solvent extracts except for distilled water extracts were able to confirm the presence of chlorophyll. Infrared absorption spectra (FT-IR) of all parts of the extracts showed broad absorption bands of OH due to phenolic-OH, benzene CH peak of phenol chemical structure, ether-based stretching vibration peak and the peak of flavonoid compounds that appeared in all the solvent extracts. The yield of juniper needles and heartwood in distilled water and methanol extraction were effective. Extraction of berry yields in distilled water was also effective. The yield of ethanol extraction from the bark showed better efficiency. As a result of using distilled water for the dye solution, the color of the fabrics dyed with all extracts of the needles and Y series berries generally showed light Y progression with a strong red tinge. By using a mixture of 20% ethanol and 80% distilled water for the dye solution, the color of the fabrics dyed with needles and berry extracts showed Y series dominantly. The color of the fabrics dyed with Bark and heartwood extracts were dominantly R series.

Accelerated Laboratory Experiments Investigating Weathering of Volcanic Rocks from Yuchon Group Exposed to Seawater and Acidified Distilled Water (실내인공풍화가속실험을 통한 해수와 산성증류수에 대한 유천층군 화산암의 풍화 특성 연구)

  • Ik Woo
    • The Journal of Engineering Geology
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    • v.34 no.1
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    • pp.25-38
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    • 2024
  • Laboratory tests of accelerated artificial weathering compared the effects of seawater and acidified distilled water on rock weathering. The experiments simulated chemical and physical weathering of five different types of volcanic rock by applying 45 freeze-thaw cycles using seawater and acidified distilled water (pH 3), both at 70℃. The physical properties and uniaxial compressive strength (UCS) of the rocks were measured after 15 and 45 cycles of artificial weathering. Most of degradation of physical properties appeared within the first 15 cycles, and acidified distilled water had a greater effect than seawater. Analysis of variance (ANOVA) statistically evaluated the differences in UCS of the different rock types during the tests. The rate of UCS reduction after 45 cycles was similar across the samples, being independent of the rock type and the trend of changes in physical properties. In contrast to the changes in the physical properties, the UCS was more affected by seawater than by acidified distilled water.

Antioxidant activities of soymilk added with green tea and rosemary extract (녹차와 로즈마리 추출물을 첨가한 두유의 항산화 활성)

  • Ryu, Ji-yeon;Song, YeonWoo;Moon, Jeong Yong;Jun, Neung-Jae;Kim Cho, Somi
    • Food Science and Preservation
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    • v.24 no.6
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    • pp.871-878
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    • 2017
  • The objective of this study was to compare antioxidant activities of green tea, rosemary, lemon and bamboo leaves extracts using three different extraction methods (80% ethanol sonication extraction, distilled water autoclave extraction, distilled water extraction at room temperature). As a result, green tea and rosemary extracts showed relatively high antioxidant activities compared with those of lemon and bamboo leaves. These green tea and rosemary extracts were subsequently added to soymilk and their mixtures were examined for antioxidant activities. Soymilk added with 10% green tea distilled water autoclave extracts and distilled water at room temperature extracts showed relatively high DPPH, $85.09{\pm}2.26%$, $84.38{\pm}1.97%$, and ABTS radical scavenging activities, $73.43{\pm}2.78%$, $81.34{\pm}4.78%$, respectively. On the other hand, soymilk added with 10% rosemary distilled water autoclave extracts showed remarkably higher DPPH radical scavenging activity while their ABTS radical scavenging ability was similar to that of non-added soymilk. In conclusion, our results suggest that the addition of green tea distilled water autoclave extracts, distilled water at room temperature extracts and rosemary distilled water autoclave extracts to soymilk could contribute to the development of added value soymilk products with increased antioxidant activities.

Dyeability and Antibacterial Activity of the Fabrics with Elm-Bark Extracts (느릅나무 껍질 추출액에 의한 섬유의 염색성 및 항균성)

  • 최영희;권오경;문제기
    • Textile Coloration and Finishing
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    • v.15 no.3
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    • pp.140-145
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    • 2003
  • The purpose of this study is searching the Elm-Bark dyes' dyeability and antibacterial activities according to the dyeing time, pH, a mordant and the method of mordancy. We used two kinds of Elm-Bark dyes which's extracted by the Electrolytic reduction water and Distilled water. Silk fabric and Cotton/nylon union fabric was used for this study. The results are as follow. K/S value is increased according to the dyeing time and the suitable pH level is pH 3. Dyeability is good with Iron(II) sulfate$(FeSO_4\cdot{7H}_2O)$ on the pre-mordancy and Potassium dichromate$(K_2Cr_2O_7)$ on the post-mordancy. The Elm-Bark dyes by the Electrolytic reduction water has good colorfastness more than by the Distilled water. Antibacterial activities is excellent and the ratio is over than 99.5%.

Extraction Characteristics of Soluble Solid from Rumex crispus(Curled Dock) Roots (소리쟁이(Rumex crispus) 뿌리로부터 가용성 고형분의 추출특성)

  • Jeong, Kap-Seop
    • Journal of Environmental Science International
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    • v.20 no.10
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    • pp.1265-1272
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    • 2011
  • In this study, the extraction characteristics of soluble solid from Rumex crispus(Curled dock) was studied from the investigation of the effects of experimental conditions on extraction rate; extraction ratio, composition of extractants, extraction time and pH of extractant, etc. The proximate composition of Rumex crispus was 2.58% crude lipid, 5.59% crude protein, 7.39% crude ash, 6.13% moisture and 78.31% carbohydrate, respectively. Turbidity of extract by distilled water was higher and increased with extraction time and extraction temperature, where as the turbidity didn't increase by ethanol and methanol in 20 folds of extraction ratio. Turbidity was inversely proportional to the extraction ratio for the three extractants at 25$^{\circ}C$ and 1 hour extraction. But turbidity of extract was highest by composition of 50% methanol-water extractant than any other compositions of extractants. Eighteen and fifteen free aminoacids were detected in extracts with distilled water, methanol and ethanol extractant, respectively, and it's contents were order of glutamic acid>proline>aminobutyric acid>alanine. The extraction rate of soluble solid from Rumex crispus was order of distilled water>methanol>ethanol within experimental extraction ratio. In extraction with distilled water, the contents of soluble solid was inversely proportional to the pH of extractant.

Change of Interfacial properties by the Fiber Degradation in the Fiber Reinforced Composites (섬유강화 복합재료에서 섬유열화에 따른 계면특성의 변화)

  • Moon, Chang-Kwon;Kim, Young-Dae;Roh, Tae-Young
    • Journal of Ocean Engineering and Technology
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    • v.12 no.3 s.29
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    • pp.31-41
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    • 1998
  • Single fiber fragmentation technique was used to evaluate the change of interfacial properties by degradation of fiber tensile strength in the fiber reinforced composites. The influences of fiber tensile strength on the interfacial properties have been evaluated by the fragmentation specimens(weak fiber samples) of glass fiber/epoxy resin that was made using the pre-degraded glass fiber in distilled water at $80^{circ}C$ for specified periods. The effects of the immersion time on the interfacial properties in the distilled water at $80^{circ}C$ also have been evaluated by the fragmentation specimens(original fiber samples) of glass fiber/epoxy resin that was made using the received glass fiber. As the result, the tensile strength of glass fiber was decreased with the increasing of the treatment time in the distilled water at $80^{circ}C$ and the interfacial shear strength was independent of the change of the glass fiber strength in the single fiber fragmentation test. But in the durability test using the single fiber fragmentation specimen, interfacial shear strength decreased with the increasing of the immersion time in distilled water ar $80^{circ}C$. And it turned out that the evaluating of interfacial shear strength using original fiber tensile strength was valuable in the durability test for the water environment by the single fiber fragmentation technique.

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