• Advances in materials Research
• /
• 제9권2호
• /
• pp.109-114
• /
• 2020

The purpose of this study was to observe the trend of compounds release from acrylic resin oral prosthesis when used for drug delivery as well as a restoration. In this study, 10 specimens of heat-cured polymethylmethacrylate material were prepared and loaded with methylene blue biological stain. The specimens were then submerged in vials with 5 ml distilled water for 24 hours. The extraction procedure continued for 4 days, each day the specimens were immersed in another 5 ml distilled water vial. All extracted solutions were analyzed by visible light spectroscopy for absorbance comparison. The statistical results showed that the absorbance values were significantly different in the first day of extraction than the following days. However, there was no statistical difference among the 2^nd, 3^rd and 4^th days of extraction. Biological stain loading to acrylic resin at the mixing stage, and then after extraction in distilled water, showed a burst release during the first day followed by a constant release during the following few days.

• 농업과학연구
• /
• 제49권3호
• /
• pp.389-396
• /
• 2022

The purpose of this study was to investigate the safety of Houttuynia cordata Thunb extract (HCE) in Institute of Cancer Research (ICR) mice, to determine the effects of the extract on the growth performance and colony count, and to establish the optimal concentration of HCE. In total, 60 five-week-old male ICR mice with an average initial body weight (BW) of 27.24 ± 0.44 g were used in a four-week experiment. Mice were randomly allotted to four treatment groups (five replications per group, three mice per cage): 1) a control (CON) group fed with normal distilled water; 2) treatment group 1 (T1) fed with normal distilled water containing 0.05% HCE; 3) treatment group 3 (T3) fed with normal distilled water containing 0.1% HCE; and 4) treatment group 3 (T3) fed with normal distilled water containing 0.2% HCE. BW, feed intake (FI), and water intake were measured on the first, fourteenth, and eighteenth days. T2 showed a significant improvement (p < 0.05) in the feed conversion ratio (FCR) over the experimental period. However, water intake levels did not show significant differences among the groups. In the large intestine and feces, E. coli and Lactobacillus levels were significantly improved (p < 0.05) in the HCE treated group compared to the CON group. Supplying HCE via the drinking water improved the growth performance and colony count in ICR mice. Based on results of this study, utilizing HCE in livestock species is expected to be safe and feasible.

• 한국식품영양과학회지
• /
• 제24권6호
• /
• pp.948-955
• /
• 1995

겨자의 항균성을 조사하기 의하여 추출용매에 따른 겨자의 항균성을 비교하고, 항균물질을 동정한 결과물, 메탄올 및 헥산에 대한 겨자 추출물의 항균성은 물 및 메탄올 추출물이 실험균주 모두에서 나타났으나 헥산에 의한 겨자 추출물은 항균활성이 거의 나타나지 않았다. SDE장치를 이용한 겨자 추출물의 항균성은 증류성분에서 항균활성이 아주 크게 나타났고, 메탄올에 의한 잔사 추출물도 항균활성이 조금 나타났으나 물층은 항균활성이 거의 나타나지 않았다. 겨자로 부터 3-iso-thiocynate-1-propene, 4-isothiocyanato-1-butene 및 4-ios-thiocyanatoethyl benzene과 같은 3종류의 isothiocyanate를 포함하여 30여종의 증류성분이 동정되었다.

• 동아시아식생활학회지
• /
• 제17권3호
• /
• pp.384-392
• /
• 2007

The primary objective of this study was to determine the effects of a water-distilled extract with 15 kinds of Korean medicinal herb on antioxidant activity, antimicrobial activity against Helicobacter pylori, and lipid metabolism. The water-distilled extract (WE) and fermenting water-distilled extract (FE) of medicinal herbs were utilized in order to make functional beverages. The EDA (electron donating activity), SOD-like ability, and RAE (relative antioxidant efficacy) of WE averaged 24.47, 50.35, and 1.57%, respectively, but the EDA, SOD-like ability, and RAE of FE was retardeded by 12.01, 35.72, and 1.55%, respectively. The antimicrobial activity against Helicobacter pylori of WE averaged 12.84 mm as a diametric clear zone, and was significantly (p<0.05) higher than those measured in the WE and control. Serum triglyceride contents, total serum cholesterol contents, and serum LDL-cholesterol contents of the WE group were significantly (p<0.05) lower than those of the control group. The liver total-cholesterol contents and liver triglycerides of WE group were significantly (p<0.05) lower than those of the control group. The plasma TBARS value of the WE group was significantly (p<0.05) lower than that of the control group. The sensory evaluation, taste, and smell of FE were more desirable than those of WE, but the color of WE was more desirable. According to the above results, the water distilled extracts (WE) of 15 kinds of medicinal herb are supposed to be effective with regard to antioxidant activity and lipid metabolism, but the antimicrobial activity against Helicobacter pylori was increased as the result of fermentation.

• 대한기계학회논문집A
• /
• 제27권3호
• /
• pp.363-371
• /
• 2003

This study is mainly concerned with phenomenon of cavitation-erosion on the several materials and corrosive liquids which were applied with vibrator(suggested by ASTM G 32, 20KHz, 50$mu extrm{m}$). The maximum erosion rate by cavitation erosion in both of distilled water and sea water appeared to be proportioned to their hardness and tensile strength. Cavitation weight loss and rate of cast iron in sea water condition were greater(approximately 3 times) than that in distilled water condition, however in case of stainless steel and brass the cavitation weight loss of composite materials were not so different in both of their conditions. Cavitation weight loss of composite materials were shown as below on this test, Duratough DL : Weight loss in sea-water condition were greater (approximately 2.3 times) than it's distilled water condition. The main tendency of cavitation erosion for metals appeared that small damaged holes causing by cavitation erosion was observed with radial pattern. On the other hand, the tendency for composites appeared that small damaged holes were observed randomly.

• 한국작물학회지
• /
• 제39권5호
• /
• pp.465-472
• /
• 1994

저온에서 볍씨종자의 발아증진을 도모하기 위하여 파종 전 종자를 PEG용액에 삼투처리 하였다. 발아율을 높이기 위한 가장 적절한 PEG-6000의 농도는 20%였으며, 침지하는 동안 온도는 20${\pm}1^{\circ}C$ 를 유지하였다. 본 실험에서 사용된 종자는 신운봉벼(조생종), 간척벼(중생종), 동진벼(중만생종)종자였는데 얻어진 결과를 요약하면 다음과 같다. 1. PEG 용액에 60시간 침지한 후 종자의 수분함량은 증류수에 24시간 침지한 후의 수분함량과 거의 같았다. 2. PEG용액에 침지한 종자의 발아능은 증류수에 침지한 종자의 발아능에 비해 특히 저온에서 현저히 높았다. 3. PEG 용액에 침지했던 종자 침출물의 전기전도도는 증류수에 침지했던 종자나 대조구보다 그 값이 낮았고, 총 탈수소효소 활성은 증류수에 침지했던 종자나 대조구보다 그 값이 높았다. 4. 배의 단백질 함량을 보기 위해 전기영동한 결과, PEG 용액에 침지한 종자는 68KD부근 band에서 증류수에 침지한 종자나 대조구보다 약간 진한색을 보였다. 5. 전기영동에 의한 배의 동위효소 조성을 본 결과 peroxidase는 신운봉벼와 간척벼에서 공통적으로 Rf 0.94에서 PEG용액에 침지한 종자가 증류수에 침지한 종자나 대조구보다 진한색을 보였고, esterase는 세 품종 공통적으로 Rf 0.87에서 peroxidase와 비슷한 양상을 보였다.

• Restorative Dentistry and Endodontics
• /
• 제23권1호
• /
• pp.379-390
• /
• 1998

In endodontic treatment, calcium hydroxide has been used as intracanal medicament. Although calcium hydroxide should be removed thoroughly before permanent root canal filling, no effective method for its removal has been reported. Because of irregularity of root canal walls, root curvatures and anatomic variations, it is insufficient to remove calcium hydroxide from the canal wall only by mechanical instrumentation Considering the chemical effects of irrigants on calcium hydroxide, $Ca^{++}$ dissolving effect from two calcium hydroxide products is investigated, using dis- tilled water, NaOCl, citric acid and EDTA. Vitapex$^{(R)}$ 0.1g and calcium hydroxide 0.03g were dissolved in distilled water, 5% NaOCl, 50% citric acid and 17% EDTA respectively, at 1, 3, 5, 10min. time interval. The solution was filtered using filter paper(pore size $5{\mu}m$) and $Ca^{++}$ concentration was determined by ion chromatography. The result were as follows : 1. Distilled water, NaOCl, citric acid and EDTA abstracted more $Ca^{++}$ from calcium hydroxide than Vitapex$^{(R)}$ except NaOCl 1, 5, 10 time interval. 2. EDTA and citric acid abstracted more $Ca^{++}$ from Vitapex$^{(R)}$ and calcium hydroxide than distilled water or NaOCl. The overall result support the view that water-based calcium hydroxide product is easily removed than oil-based calcium hydroxide product and EDTA, citric acid are more effective in $Ca^{++}$ elution than NaOCl or distilled water.

• Restorative Dentistry and Endodontics
• /
• 제17권1호
• /
• pp.104-114
• /
• 1992

The purpose of this study was to evaluate the shear bond strength of glass ionomer cement(Ketacfil, ESPE, Co.) against dentin surface which had been treated with surface conditioning agents(distilled water, 5% sodium hypochlorite solution, Ketac - conditioner, 40% polyacrylic acid). In this study, 60 human molars with sound and healthy crown portion which were previously extracted for orthodontic or periodontal problem. The dentin surfaces of these teeth were exposed with wet trimmer and polished with 150 - grit and 600 - grit silicon carbide paper and the teeth were divided into four groups(15 teeth per group) according to the following surface conditioning methods. Group I : Surface treatment with distilled water as control group. Group II : Surface conditioning with 5% sodium hypochlorite solution. Group III : Surface conditioning with Ketac conditioner. Group IV : Surface conditioning with 40% polyacrylic acid. The shear bond strengths were measured by Autograph(Shimatzu Co. Japan). The result of the evaluations were then subjected to statistical analysis using one - way analysis of variance and Duncan test and the results were as follows : 1. The shear bond strength accrding to the dentin surface conditioning conditions was highest in Ketac conditioner group, with measurements of $44.44{\pm}0.74(kg/cm^2)$ and lowest in the distilled water group, with measurements of $28.84{\pm}0.88(kg/cm^2)$. 2. Statistically significant differences were found between surface conditioning with 5% sodium hypochlorite solution group or Ketac conditioner group and distilled water group(P<0.01). 3. Also, statistically significant difference was found between surface conditioning with distilled water group and 40% polyacrylic acid group(P<0.05). 4. Overall difference in statistical significance between the groups was not found (P<0.05). 5. Fractured dentin surface treated with conditioning solutions showed cohesive fracture. 6. Distilled water group and 5% sodium hypochlorite solution group removed the smear layer less effectively. 7. Conditioning dentin with Ketac conditioner and 40% polyacrylic acid resulted in the removal of a significant amount of the smear layer without removing the tubular plugs and dissolving the peritubular dentin.

• Composites Research
• /
• 제26권3호
• /
• pp.165-169
• /
• 2013

This work presents the tensile properties and water uptake behavior of plasma treated abaca fibers reinforced epoxy composites. The composites were prepared by vacuum assisted resin transfer molding. The effects of treatment on tensile properties and sorption characteristics of abaca fiber composites in distilled water and salt solution at room temperature were investigated. The tensile strength of the composites increased with plasma treatment. With plasma treatment, an improvement of 92.9% was obtained in 2.5 min exposure time in plasma. This is attributed to high fiber-matrix compatibility. Less improvement on tensile properties of hybrid treatment of sodium hydroxide and plasma was obtained. However, both treatments reduced overall water uptake in distilled water and salt solution. Hydrophilicity of the fibers decreased upon plasma and sodium hydroxide treatment, which decreases water uptake.

• 한국식품저장유통학회지
• /
• 제10권3호
• /
• pp.326-332
• /
• 2003

해양 심층수는 일본, 미국 등에서 200 m 이하의 심해에서 취수되고 있으며, 물의 특성으로 부영양성, 저온안정성 및 청정성을 들 수 있다. 본 연구에서는 발효빵의 효모증식에 대한 해양 심층수와 그 염의 효과에 대해 조사하였다. 해양 심층수와 심층수염을 첨가하여 발효한 빵의 부피증가율은 증류수만을 사용한 빵보다 높게 나타났다. 또한 해양 심층수를 이용한 식빵의 기공 형태는 증류수로 제조된 식빵의 기공보다 둥글고 일정하였다. 한편, 식빵의 전반적인 기호도에서 증류수와 심층수염을 혼합하여 첨가한 식빵이 6.56으로 가장 높은 관능평점을 나타내었다.