• 제목/요약/키워드: distilled water

검색결과 2,421건 처리시간 0.035초

Antimicrobial activity against Propionibacterium acnes bacteria of Smilacis glabrae Rhizoma extracts (토복령 추출물의 여드름 균에 대한 항균활성)

  • Park, Jang-Soon;Kwon, Hye-Jin
    • Journal of the Korea Convergence Society
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    • 제8권12호
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    • pp.425-430
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    • 2017
  • This study was conducted to measure the antimicrobial activity and antiseptic effect of Smilax china root extracts against Propionibacterium acnes and to develop natural antimicrobial extracts as an alternative for synthetic preservatives, which have recently been controversial. Extracts were obtained from dried Korean Smilax china root at room temperature using two solvents, distilled water and 95% EeOH, separately. According to the results of this study, the antimicrobial effect of Propionibacterium acnes 3314 and Propionibacterium acnes 3320 against Propionibacterium acnes was outstanding. In particular, the clear zone of the extract using distilled water showed the highest activity with 16.61 mm. As for the result of the collection of contaminated skin sample, the clear zone was 24.48 mm. This indicates that Smilax china root extracts show a high activity against skin flora as well as a high antimicrobial activity against Propionibacterium acnes. In conclusion, it is confirmed that Smilax china root extracts can be used as raw materials for cosmetics that have antimicrobial activity and antiseptic effect, and it is expected that Smilax china root extracts will be used as basic materials for the development of future natural preservatives.

Effects of the Concentration and the Temperature on the Thermophysical Properties of Purely-Viscous Non-Newtonian Fluid (순수점성 비뉴톤유체의 물성치들에 대한 농도 및 온도의 영향)

  • 조금남
    • Transactions of the Korean Society of Mechanical Engineers
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    • 제18권3호
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    • pp.670-680
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    • 1994
  • The thermophysical properties of Non-Newtonian fluid as the function of the temperature and the concentration are needed in many rheological heat transfer and fluid mechanics problems. The present work investigated the effects of the concentration and the temperature on the thermophysical properties of purely-viscous Non-Newtonian fluids such as the isobaric thermal expansion coefficient, density, zero-shear-rate viscosity, and zero-shear-rate dynamic viscosity within the experimental temperature range from $25^{\circ}C$ to $55^{\circ}C$. The densities of the test fluids were determined as the function of the temperature by utilizing a reference density and the least square equation for the measured isobaric thermal expansion coefficient. As the concentration of purely-viscous Non-Newtonian fluid was increased up to 10,000 wppm, the densities were proportionally increased up to 0.4%. The zero-shear-rate viscosities of test fluids were measured before and after the measurements of the first thermal expansion coefficients and the densities of Non-Newtonian fluid. Even though they were changed up to approximately 22% due to thermal aging and cycling, they had no effects on the thermal expansion coefficients and the densities of Non-Newtonian fluid. The zero-shear-rate dynamic viscosities for purely-viscous Non-Newtonian fluids were compared with the values for distilled water. They showed the similar trend with the zero-shear-rate viscosities due to small differences in the densities for both distilled water and purely-viscous Non-Newtonian fluid.

Development of Seawater Distiller utilizing Waste Heat of Portable Electric Generators (발전기 폐열 이용 소형 해수담수화장치 개발)

  • Park, Chang-Dae;Lim, Byung-Ju;Hiroshi, Tanaka
    • Transactions of the Korean Society of Mechanical Engineers B
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    • 제34권6호
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    • pp.607-613
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    • 2010
  • A seawater distiller, in which the waste heat from a portable electric generator was used, with a multiple-effect diffusion still was designed. The waste gas from small generators commonly used in islands has not yet been used because it has less thermal energy; however, this waste gas can be used as a heat source for small-capacity distillers and as an additional heat source for solar stills. The proposed distiller comprises a series of closely spaced parallel partitions that are placed in contact with saline-soaked wicks. In the distiller, evaporation and condensation processes are repeated to recycle the thermal energy for increasing the distillate productivity. Experimental results show that the proposed distiller with only one-effect still can produce at least 6.7 kg/day of distilled water; the proposed distiller with a ten-effect still is expected to produce 43 kg/day of distilled water. This amount of distillate is approximately four times the maximum daily productivity of the solar stills, as determined in outdoor experiments.

THE EFFECT OF TEMPORARY CEMENT AND DESENSITIZER ON THE BOND STRENGTH OF LUTING CEMENTS (접착용 시멘트의 결합강도에 임시 접착제와 탈감작제가 미치는 영향)

  • Sun Se-Na;Yang Hong-So;Park Sang-Won
    • The Journal of Korean Academy of Prosthodontics
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    • 제40권4호
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    • pp.335-343
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    • 2002
  • This study investigated the effect of temporary cement and desensitizer on the bond strength of luting cements. Total 96 dentin specimens were divided into two groups with and without temporary cementation. For temporary cement-tread group, specimens were cemented with $Temp-bond^{(R)}$ and all specimens were stored in distilled water at $37^{\circ}C$ for 7 days. Each cup was further divided into 3 subgroups with $Gluma^{(R)},\;One-step^{(R)}$ application and without desensitizer After desensitizer application, Ni-Cr specimens were luted to dentin surface with $Panavia-F^{(R)}$ and $Vitremer^{(R)}$ Specimens were placed in distilled water at $37^{\circ}C$ for 24 hours and shear bond strength between metal and dentin was measured by a universal testing machine. The results were as follows : 1. In $Panavia-F^{(R)}$ cemented groups, the combination of $One-step^{(R)}$ without temporary cement showed the greatest strength. Among the desensitizer types, $One-step^{(R)}$ showed the highest bond strength, followed by No-desensitizer, $Gluma^{(R)}$. 2. In $Vitremer^{(R)}$ cemented groups, the combination of no temporary cement and without desensitizer showed the greatest bond strength. Among the desensitizer types, No-desensitizer group showed the highest bond strength. 3. The use of $Gluma^{(R)}$ significantly reduced the shear bond strength in $Panavia-F^{(R)}$ and $Vitremer^{(R)}$ groups. 4. All temporary cement-treated groups showed a significant lower shear bond strength than without temporary cement groups. 5. Desensitizer application significantly influenced the bond strength of the resin cement and resin modified glass ionomer cement.

Functional Ingredients of Perilla Frutescens L. Britt Extracts and Preparation of PVA Nanoweb Containing Extracts (자소 추출물의 기능성 성분과 자소 추출물을 함유하는 PVA 나노 섬유의 제조)

  • Wang, Qian Wen;Lee, Jung-Soon
    • Textile Coloration and Finishing
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    • 제29권4호
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    • pp.256-267
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    • 2017
  • The purpose of this study was to analyze the functional ingredients of Perilla Frutescens L. Britt extracts and to confirm the possibility of producing PVA nanofibers using extracts. Distilled water, 3% aqueous sodium hydroxide solution and ethanol were used as extraction solvents. The electrospinning was carried out at a PVA concentration of 12%, an applied voltage of 10 kV and a tip to collector distance of 15cm. The contents of volatile substances, essential oils, total polyphenols and flavonoids of the extracts were measured to examine the constituents of functional materials. Flavor components and esters were identified in 3% sodium hydroxide and ethanol extracts. The content of polyphenols and flavonoids in ethanol extracts was higher than that of medicinal plants. 1wt.% of Tween 20 was added to disperse the essential oil components of the ethanol extract. Addition of a dispersant made it possible to produce a homogeneous mixture by having some compatibility with the ethanol extracts and the PVA molecule. When the concentration of the ethanol extract was 0.25 and 0.5wt%, relatively uniform PVA nanofiber having an average diameter of 350 to 365nm could be produced. The results of FT-IR, XRD and DSC analysis confirmed that Perilla Frutescens L. Britt ethanol extract was well mixed with PVA molecules and was electrospun.

Anti-Oxidant and Hepatoprotective Activities of Ziziphus mucronata Fruit Extract Against Dimethoate-Induced Toxicity

  • Kwape, Tebogo Elvis;Chaturvedi, Padmaja;Kamau, Macharia;Majinda, Runner
    • Journal of Pharmacopuncture
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    • 제16권1호
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    • pp.21-29
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    • 2013
  • Objective: The study was carried out to evaluate the hepatoprotective and antioxidant potential of Ziziphus mucronata (ZM) fruit extract. Methods: The different types of fruit extract were prepared by soaking the dry powdered fruit in different solvents followed by rotary evaporation. Each extract was tested for its phenol content and antioxidant activities. An in vivo study was performed in Sprague-Dawley (SD) rats. Thirty adult male SD rats (aged 21 weeks) were divided into six groups of five rats each and treated as follows: The normal control (NC) received distilled water while the dimethoate control (DC) received 6 mg/kg.bw.day-1 dimethoate dissolved in distilled water. The experimental groups E1, E2, E3, and E0 received dimethoate (6 mg/kg.bw) + ZMFM (100 mg/kg.bw-1), dimethoate (6 mg/kg.bw) + ZMFM (200 mg/kg.bw-1), dimethoate (6 mg/kg.bw) + ZMFM (300 mg/kg.bw-1), and ZMFM (300 mg/kg.bw-1) only. Both the normal control and the dimethoate control groups were used to compare the results. After 90 days, rats were sacrificed, blood was collected for biochemical assays, and livers were harvested for histological study. Results: High phenol content was estimated, and 2, 2-diphenyl-1-picryl hydrazyl radical (DPPH) spectrophotometric, thin layer chromatography (TLC) and 2, 2-Azobis-3-ethyl benzothiazoline-6-sulphonic acid (ABTS) assays showed a high antioxidant activity among the extracts. The preventive effects observed in the E1, E2 and E3 groups proved that the extract could prevent dimethoate toxicity by maintaining normal reduced glutathione (GSH), vitamin C and E, superoxide dismutase, catalase, cholineasterase and lipid profiles. The preventive effect was observed to be dose dependent. The EO group showed no extract-induced toxicity. Histological observations agreed with the results obtained in the biochemical studies. Conclusion: The study demonstrated that ZM methanol fruit extract is capable of attenuating dimethoate-induced toxicity because of its high antioxidant activity.

Effects of Cyperi Rhizoma(CR) on the Polycystic Ovaries Induced by Estradiol Valerate in Rats (향부자가 estradiol valerate로 유발된 백서의 다낭성 난소에 미치는 영향)

  • Yang, Dong-Seon;Yang, Dong-Seon;Cho, Seong-Hee;Park, Kyung-Mi;Kim, Hyung-Woo;Cho, Su-In
    • The Journal of Korean Obstetrics and Gynecology
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    • 제23권4호
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    • pp.35-46
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    • 2010
  • Purpose: This study was designed to investigate the effects of Cyperi Rhizoma (CR) on changes in weights morphological and histopathological observations in Polycystic Ovary(PCO) rats. Methods: PCO was induced by single intramuscular injection with EV(2mg) in female rats. Normal group(n=8) were injected with sesame oil and orally administrated distilled water for five weeks. PCO control group(n=8) were injected with EV and orally administrated distilled water for five weeks. CR treated group(n=8) were injected with EV and orally administrated CR for five weeks. Then we measured weight of body, ovaries. The histopathology changes of ovaries, and the expression of nerve growth factor(NGF) were also evaluated. Results: Single injection of EV induced suppression of weight gain, formation of cysts, increase of NGF expression. Oral administration of CR prevent suppression of weight gain shown in control group. In addition CR group showed upward tendency of ovarian size. Formation of cystic follicles induced by EV injection is suppressed by CR treatment. In additon, CR treatment lowered expression levels of nerve growth factor(NGF), which were elevated by induction of PCOS. Conclusion: These results suggest that CR can be used for patients with PCOS to prevent formation of cystic follicles and malfunction of ovary. And also suggest that the related mechanisms are involved in suppression of NGF expression.

An Experimental Study on Pressure Drop and Heat Transfer Coefficient of Laminar Ag Nanofluid Flow in Mini-Tubes (은 나노유체의 미세관내 층류 유동의 압력강하 및 열전달계수에 관한 실험적 연구)

  • Kwon, Jeong-Tae;Nahm, Taek-Hun;Kim, Tae-Wan;Kwon, Young-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제10권12호
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    • pp.3525-3532
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    • 2009
  • This study presents the heat transfer and pressure drop characteristics of Ag nanofluid in mini-tubes(outer diameters of 1/8inch, 3/16inch). Experiments were performed for Reynolds numbers ranged from 500 to 2,500 and nanofluid concentrations of 0.1 and 0.3vol.%. The pressure drop of nanofluid flow increased by max. 21% compared with that of distilled water. The heat transfer coefficients of the nanofluid of 0.1 vol.% enhanced 3~42% for 1/8inch tube, and 3~69% for 3/16inch tube. Also, the heat transfer coefficients of the nanofluid of 0.3 vol.% enhanced 35~65% for 1/8inch tube, and 62~125% for 3/16inch tube. From the results Ag nanofluid can be a better candidate as a coolant than distilled water when using in mechanical and/or electronic systems.

The Involvement of AMPA Receptor in the Antidepressant-like Effects of the Portulaca Oleracea L. Extract in Mice

  • Park, Soo-Jin;Choi, Min-Ji;Chung, Sun-Yong;Kim, Jong-Woo;Cho, Seung-Hun
    • Journal of Oriental Neuropsychiatry
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    • 제24권3호
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    • pp.271-280
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    • 2013
  • Objectives : The development of natural drugs with antidepressant effects is important and needed. This study was performed to investigate the antidepressant-like effects of the distilled water extract of Portulaca oleracea L. (POL) in a mouse model and to investigate the role of ${\alpha}$-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptors in producing these antidepressant-like effects. Methods : The forced swim test (FST) and tail suspension test (TST) were used to investigate the behavioral anti-depressive-like effects of POL in mice. Additional behavioral experiments with 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo[f]quinoxaline-2,3-dione, an AMPA receptor antagonist, were undertaken to determine the involvement of the antidepressant-like properties of POL in AMPA receptor throughput. Results : Oral administration of the POL extract (100 mg/kg) 1 h prior to testing significantly reduced the immobility times in the FST and TST. The antidepressant-like effects of the POL extract were not increased in a dose-dependent manner. Pre-treatment with NBQX significantly attenuated the reduction in immobility time induced by the POL extract in the FST. Conclusions : The distilled water extract of POL has antidepressant-like effects, which may be related to AMPA receptor. Pre-treatment with NBQX significantly attenuates the reduction in immobility time induced by the POL extract in the FST.

Bioavailability of Tripotassium Dicitrato Bismuthate by ICP-MS in Human Volunteers (ICP-MS를 사용한 구연산비스마스칼륨 (Tripotassium dicitrato bismuthate)의 생체이용률 측정)

  • Kwon, Oh-Seung;Kwon, Jee-Young;Yoon, Ae-Rin;Park, Kyung-Soo
    • Journal of Pharmaceutical Investigation
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    • 제37권2호
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    • pp.79-84
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    • 2007
  • This study was aimed to establish analytical method of Bi to develop a guideline of the bioequivalence test of tripotassium dicitrato bismuthate (TDB). For this purpose, a simple, specific and sensitive inductively coupled plasma-mass spectrometry (ICP/MS) method were developed and validated in human plasma. Various concentrations of bismuth standard solution (0-25ng/mL) were prepared with distilled water and human blank plasma. To 10mL of the volumetric flasks, 2mL of blank plasma was added with 8ml of distilled water. Bi standard solution was added to prepare the calibration samples and injected into ICP-MS. The plasma samples obtained from volunteers given 3 tablets of bismuth (total 900mg as TDB) were analyzed as described above. As a result, the coefficients of variation were <20% in quantitation limit (0.2 ng/mL) and <15% at the rest of concentrations. The stability test by repeated freezing-thawing cycles showed that the samples were stable only for 24hr. The stability tested for samples with a short-term period of storage at room temperature and pre-treatment prior to the analysis showed very stable over 24hr. In 8 healthy Korean subjects received Denol tablets at the dose of 900mg bismuth, AUC, $C_{max},\;T_{max}$ and half-life $(t_{1/2})$ were determined to be $198.33{\pm}173.78 ng{\cdot}hr/mL,\;64.48{\pm}27.06 ng/mL,\;0.52{\pm}0.21 hr,\;and\;5.15{\pm}2.67 hr$, respectively, from the plasma bismuth concentration-time curves. In conclusion, the method was suitable for the determination of bismuth in human plasma samples and could be applied to bioequivalence test of bismuth tablet.