• Title/Summary/Keyword: distilled water

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THE INFLUENCE OF SURFACE TREATMENTS ON THE SHEAR BOND STRENGTH OF RESIN CEMENTS TO IN-CERAM CORE (In-Ceram 코아의 표면처리 방법에 따른 레진시멘트와의 전단결합강도에 관한 연구)

  • Yoon, Jeong-Tae;Lee, Sun-Hyung;Yang, Jae-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.38 no.2
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    • pp.129-146
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    • 2000
  • An increasing demand for esthetic restorations has led to the development of new ceramic systems. In-Ceram, a glass-infiltrated alumina ceramic has three to few times greater flexural strength than other ceramic glass material. Because of its high strength, In-Ceram has been suggested as inlay, crown, laminate veneer and core material for resin bonded fixed partial dentures. This clinical application requires a stable resin bond to In-Ceram core. The purpose of this study was to evaluate the shear bond strength between In-Ceram core and resin cements according to various surface treatments and storage conditions. The surface of each In-Ceram core sample was subjected to one of the following treatments and then bonded to Panavia 21 or Variolink II resin cement. ; (1) sandblasting with $110{\mu}m$ aluminum oxide powder, (2) sandblasting and silanization, (3) sandblasting and Siloc treatment, (4) sandblasting and Targis link application. Each of eight bonding groups was tested in shear bond strengths after the following storage times and thermocycling. ; A) 24 hours storage in distilled water at $37^{\circ}C$, B) 5 weeks storage in distilled water at $37^{\circ}C$ C) 5 weeks storage in distilled water at $37^{\circ}C$ and thermocycled 2,000 thormocycling for every 10 days(totally 10,000 thermocycting) in $5^{\circ}C-55^{\circ}C$ bath. The bond failure modes were observed with scanning electron microscope(SEM). The results were as fellows : 1 The shear bond strengths of sandblasting group were significantly lesser than the other groups after 24 hours water storage. No significant difference of bonding strengths was found between storage time conditions(24 hours and 5 weeks). The shear bond strengths showed a tendency to decrease in Variolink II bonding groups and to increase in Panavia 21 bonding groups. 3. After thermocycling, the shear bond strengths of all groups were significantly decreased(p<0.01) and Targis link group exhibited significantly greater strengths than the other groups(p<0.05). 4. Panavia 21 bonding groups exhibited significantly greater bonding strengths in sandblasting group(p<0.01) and silane group(p<0.05) than Variolink II bonding groups. 5. In observation of bond failure modes, Targis link group showed cohesive failure in resin part and silane group and Siloc group showed complex failure and sandblasting group showed adhesive failure between In-Ceram and resin.

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Lateral Penetration of Water in Ray Parenchyma Cells of Castanea crenata

  • Ahmed, Sheikh Ali;Chong, Song-Ho;Chun, Su-Kyoung
    • Journal of the Korea Furniture Society
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    • v.19 no.2
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    • pp.137-140
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    • 2008
  • This experiment states the ultra pure distilled water penetration depth through ray parenchyma cell in radial direction of Castanea crenata. Heartwood penetration depth was 1.16 times lower than the depth in softwood and that difference was found statistically significant at 75.2 second of penetration. Following go-stop-go cycle, water penetrated in the ray parenchyma cell. At the beginning this speed was high and then it was decreased slowly. Water penetration depth result was compared with alcohol penetration depth. It was found that water penetration in ray parenchyma was found lower than alcohol due to the low surface tension of water.

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Changes of Physiological Activity of Mustard Leaf during Its Fermentation Period

  • Lim, Hyun-Soo;Yoo, Eun-Jeong;Choi, Myeong-Rak
    • Journal of Microbiology and Biotechnology
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    • v.10 no.1
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    • pp.43-47
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    • 2000
  • In vitro cytotoxicity and antioxidative effects of water extracts prepared from Mustard Leaf Kimchi (MLK) during its fermentation period were investigated. The cytotoxicity against HepG2 (human hepatic cancer) by water extracts from the well fermented Mustard Leaf Kimchi was higher than others (fermented for 0 to 6 days at 18$^{\circ}C$), and IC50 of water extracts at the points of 6, 8, 10, and 14days during fermentation were 213.4, 99.2, 99.9, and 109.8${\mu}{\textrm}{m}$/ml, respectively. Antioxidative activity of water extracts from MLK during various fermentation periods was higher than that of blank distilled water. However, the antioxidative activity of well-fermented water extracts of MLK (fermented for 8-14 days) did not show any difference from that of others (fermented for 2-6 days). Thus, water extracts of well-fermented MLK (fermented during 8-14 days) significantly inhibited the growth of cancer cells in vitro, but little antioxidative activity was influenced by the various fermentation periods.

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An Electron Microscopic Structure of Rotavirus by Negative Stain (Negative stain을 이용한 Rotavirus의 투과전자현미경적 구조)

  • Kwon, Jung-Kyun
    • Applied Microscopy
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    • v.24 no.4
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    • pp.107-114
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    • 1994
  • The Rotaviruses are members of the family Reoviridae and are the major cause of severe childhood gastroenteritis worldwide. Recently, electron microscopy has been used to detect non-group A rotaviruses to determine a relatively high resolution structure of the rotavirion. Mature, infectious virions(double-shelled particles) have a diameter of approximately 70nm, and have a capsid structure composed of two concentric protein layers. We have studied patient's stool specimen by negative staining technique complete removal of sucrose suspension. This negative staining technique that could be carried out in about 30 minutes and that could be used with crude stool specimen was an advantage of major significance. Removal of sucrose in the sample by has been completed washing with distilled of sucrose and by washing with distilled water. Ultrastructurally, typical feature of rotavirus has a double capsid construction with an inner capsid of 55nm and on outer 65-70nm diameter can be clearly demonstrated.

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The Effect of Various Coffees on the Color Stability of Self-cured Temporary Crown Resin (커피종류에 따른 자가중합형 임시치관용 레진의 색 안정성에 관한 연구)

  • Hwang, Su-Hyun;Yu, Ji-Su;Han, Yang-Keum
    • Journal of dental hygiene science
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    • v.12 no.4
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    • pp.342-347
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    • 2012
  • This study is a temporary crowns and the period you want to avoid the exposure of the coffee girl polymerization types is difficult given the temporary tolerance by producing resin. 1. Change of brightness ($L^*$) edge in time increases, distilled water, Americano, Cafelatte, Vanillalatte was reduced to a significant level of brightness (p<.001). The most significant decrease in brightness of the Americano, which tend to grow out of a Cafelatte, Vanillalatte, which was followed by distilled water. 2. Change of redness ($a^*$) edge in time tend to increase saturation increases, the redness value of Americano, Cafelatte, redness value was a statistically significant difference in distilled water and Vanillalatte (p<.05) was not significant. 3. Change of yellowness ($b^*$) edge in time tend to increase saturation increases, the yellowness value of Cafelatte, Vanillalatte, Americano, except for distilled water at the saturation of yellowness value were no statistically significant (p<.05). 4. Change of color difference (${\Delta}E^*$) in order of (Americano>Cafelatte>Vanillalatte) as time of immersion increases change of color difference appear and no statistically significant (p<.05). Americano, the edge, since there can be more than chrominance is 3.3 uses station than a Vanillalatte, Cafelatte and discoloration when edge in 28, since even in the one to two difficult to distinguish with the naked eye as a discoloration. It was no difference statistically in color difference (${\Delta}E^*$) value in distilled water (p>.05).

Longitudinal Penetration of Water through the Vessel and Wood Fiber in Castanea crenata

  • Ahmed, Sheikh Ali;Chun, Su-Kyoung
    • Journal of the Korea Furniture Society
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    • v.19 no.2
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    • pp.111-115
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    • 2008
  • An experiment was conducted to know ultra-pure distilled water penetration depth through large vessel, small vessel, latewood fiber and earlywood fiber in longitudinal direction of Castanea crenata. In heartwood, latewood fiber transported water more than large and small vessel. While in sapwood, small vessel conduction depth was found the highest. Penetration depth of water after 15.0 seconds, no significant difference was observed among earlywood fiber, latewood fiber and earlywood vessel. Whilst in heartwood, no statistical difference was observed among earlywood fiber, latewood fiber and earlywood vessel. At the beginning, the speed of water penetration was high and then gradually decreased.

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Acceleration Test of Ion Migration for PCB Electronic Reliability Evaluation (PCB 전기적 신뢰성평가를 위한 이온 마이그레이션 가속시험)

  • Lee, D.B.;Kim, J.H.;Kang, S.K.;Chang, S.W.;Lim, J.H.;Ryu, D.S.
    • Journal of Power System Engineering
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    • v.9 no.1
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    • pp.64-69
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    • 2005
  • In evaluation of electronic reliability on the PCB(Print Circuit Borad),electrochemical migration is one of main test objects. The phenomenon of electrochemical migration occurs in the environment of the hight humidity and the hight temperature under bias through a continuous aqueous electrolyte. In this paper, the generating mechanism of electrochemical migration is investigated by using water drop acceleration test under various waters. The waters used in the water drop test are city water, distilled water and ionic water. It found that the generated velocity of electrochemical migration depended on electrolyte quantity which included in the various waters.

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Physiological Functionality of Various Extracts from Danmemil and Legumes (단메밀과 콩 추출물들의 생리 기능성)

  • 김동희;이국영;김나미;이종수
    • The Korean Journal of Food And Nutrition
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    • v.16 no.4
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    • pp.347-352
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    • 2003
  • Physiological functionalities of various extracts from Danmemil and legumes were determined and its optimal extraction conditions were also investigated. Angiotensin I-converting enzyme (ACE) inhibitory activity and tyrosinase inhibitory activity of Danmemil were higher in water extracts (53%, 58%) than those of ethanol extracts. However, its electron-donating ability was the highest in ethanol extracts (72%). ACE inhibitory activity and electron-donating ability of Black bean No. 1 and Taekwangkong(one of bean) were higher in water extracts than those of ethanol extracts, whereas SOD-like activity was the highest in ethanol extracts. ACE inhibitor and tyrosinase inhibitor of Danmemil were maximally extracted when it were treated with 20 times of distilled water at 35$^{\circ}C$ for 24 h and 36 h, respectively. Its electron donating compound was maximally extracted by treatment of 50$^{\circ}C$ for 18 h. ACE inhibitor of Black bean No. 1 was extracted maximally when it was treated with distilled water (1 :20) at 20$^{\circ}C$ for 24 h, whereas the other functional compounds were maximally extracted at 20$^{\circ}C$ for 18 h.

Oligotrophic Media Compared with a Tryptic Soy Agar or Broth for the Recovery of Burkholderia cepacia Complex from Different Storage Temperatures and Culture Conditions

  • Ahn, Youngbeom;Lee, Un Jung;Lee, Yong-Jin;LiPuma, John J.;Hussong, David;Marasa, Bernard;Cerniglia, Carl E.
    • Journal of Microbiology and Biotechnology
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    • v.29 no.10
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    • pp.1495-1505
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    • 2019
  • The Burkholderia cepacia complex (BCC) is capable of remaining viable in low-nutrient environments and harsh conditions, posing a contamination risk in non-sterile pharmaceutical products as well as a challenge for detection. To develop optimal recovery methods to detect BCC, three oligotrophic media were evaluated and compared with nutrient media for the recovery of BCC from autoclaved distilled water or antiseptic solutions. Serial dilutions ($10^{-1}$ to $10^{-12}CFU/ml$) of 20 BCC strains were inoculated into autoclaved distilled water and stored at $6^{\circ}C$, $23^{\circ}C$ and $42^{\circ}C$ for 42 days. Six suspensions of Burkholderia cenocepacia were used to inoculate aqueous solutions containing $5{\mu}g/ml$ and $50{\mu}g/ml$ chlorhexidine gluconate (CHX) and $10{\mu}g/ml$ benzalkonium chloride (BZK), and stored at $23^{\circ}C$ for a further 199 days. Nutrient media such as Tryptic Soy Agar (TSA) or Tryptic Soy Broth (TSB), oligotrophic media (1/10 strength TSA or TSB, Reasoner's $2^{nd}$ Agar [R2A] or Reasoner's $2^{nd}$ Broth [R2AB], and 1/3 strength R2A or R2AB) were compared by inoculating these media with BCC from autoclaved distilled water and from antiseptic samples. The recovery of BCC in water or antiseptics was higher in culture broth than on solid media. Oligotrophic medium showed a higher recovery efficiency than TSA or TSB for the detection of 20 BCC samples. Results from multiple comparisons allowed us to directly identify significant differences between TSA or TSB and oligotrophic media. An oligotrophic medium pre-enrichment resuscitation step is offered for the United States Pharmacopeia (USP) proposed compendial test method for BCC detection.

Antioxidative Activity of Various Solvent Extracts of Quercisemen to Linoleic Acid (상수리(상실(橡實))의 각종 용매 추출물이 linoleic acid의 항산화력에 미치는 영향)

  • Sin, Du-Ho;Jo, Jeong-Sun
    • Journal of the Korean Applied Science and Technology
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    • v.8 no.1
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    • pp.79-83
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    • 1991
  • The extracts of Quercisemen(Quereus acutissima Carruthers seed) powder was obtained by the extraction with distilled water, water : acetonet(1:1, v/v), ethanol and ethyl ether, respectively. As a result this experiment, the antioxidative activity of each solvent extracts on linoleic acid were examined as follows: 1. Each fraction extracted by the acetone : water(1:1, v/v), water and ethanol respectively showed high antioxidative activity. 2. A fraction of the tannin extracted from the solvent, acetone, water(1:1, v/v) showed even more antioxidative activity than that of the ${\alpha}$-tocopherol or BHT. 3. Acceleration of peroxide reaction by $Fe^{++}$ and $Cu^{++}$ on the linoleic acid was strongly inhibited by adding the tannin, 4. Organic acid, such as malic acid, citiric acid and tartaric acid with the tannin were showed the synergistic effect fo the antioxidation reaction.