• 제목/요약/키워드: solvent effect

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Sorption Characteristics of Butanol/Water and Isopropanol/Water Solutions on the FASs Coated Inorganic Membrane (FASs로 코팅한 무기막에 대한 부탄올/물, 이소프로판올/물 용액의 수착 특성)

  • Lee, Kwang-Rae
    • Membrane Journal
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    • v.28 no.5
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    • pp.320-325
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    • 2018
  • The sorption amounts of butanol/water and isopropanol/water solution on the surface modified with FASs (fluoroalkylsilanes) hydrophobic membrane were measured and analyzed using Hansen's solubility parameters. The difference of the solubility parameter of butanol (${\delta}_t=20.4$) and that of the surface modified with FASs hydrophobic membrane (${\delta}_t=16.9$) was greater than the case of isopropanol (${\delta}_t=24.6$), which might explain the result that the sorption amount of butanol was much higher than that of isopropanol. We might also explain the effect of the polar force (${\delta}_p$) on the sorption amount. The difference (${\Delta}$) between FASs polar force (${\delta}_p=4.6$) and butanol polar force (${\delta}_p=6.3$) was much smaller than that between FASs polar force (${\delta}_p=4.6$) and isopropanol polar force (${\delta}_p=9.0$), which meant that the interaction of butanol-FASs was much greater than that of isopropanol-FASs, and resulted in greater sorption amount of butanol on the FASs. This study showed Hansen's solubility parameters might be used for analysis of sorption characteristics of alcohol on membrane and solubility of solute in solvent.

A Study of Drag Reduction by Polymer-Surfactant Mixture System (고분자-계면활성제 혼합물에 의한 마찰저항 감소연구)

  • Kim, Jeong-Tae;Kim, Cheol-Am;Choe, Hyeong-Jin;Kim, Jong-Bo;Yun, Hyeong-Gi;Park, Seong-Ryong
    • Korean Journal of Materials Research
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    • v.8 no.2
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    • pp.135-140
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    • 1998
  • Drag reduction produced by dilute solution of water soluble ionic polymer-surfactant complex under turbulent flow in a rotating disk apparatus(RDA) was investigated in this study. Three different molecular weights of polyacrylic acid(PAA) were adopted as drag reducing additives, and distilled water was used as a solvent. Experiments were undertaken to observe the dependence of drag reduction on various factors such as polymer molecular weight, molecular expansions and flexibility, rotating speed of the disk and polymer concentration. Specific considerations were put on conformational difference between surfactant and polymer, and effect of pH on ionic polymer possessing various molecular conformation through pH. The complex of ionic polymer and surfactant(Sodium Dodecyl Sulfate) behaves like a large polyelectrolyte. Surfactant changes the polymer conformation and then increases the dimension of the polymer. The radius of gyration, hydrodynamic volume and relative viscosity of the polymer-surfactant system are observed to be greater than those of polymer itself. Such surfactant-polymer complex has enhanced drag reduction properties.

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A study on synthesis of polyurethane dispersion by $H_{12}MDI$ and how effect to mechanical properties by ammonium dihydrogen phosphate ($H_{12}MDI$를 이용한 수분산 폴리우레탄 수지의 합성 및 ammonium dihydrogen phosphate에 의한 물성변화에 관한 연구)

  • Lee, Joo-Youb;Nam, Sang-Sung
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.1
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    • pp.74-82
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    • 2014
  • For this research, prepared ammonium dihydrogen phosphate aqueous solution and polyurethane dispersion. Use these resin, this article has been analyzed about change of mechanical properties by increasing amount of ammonium dihydrogen phosphate aqueous solution in polyurethan resin on coated leather and dried film. According to measure data for solvent resistance, DPU(polyurethane dispersion) resin and DPU-AD1, D2, D3(samples of polyurethaneresin with ammonium dihydrogen phosphate aqueous solution) had good property. As known in the results, increase of ammonium dihydrogen phosphate constant did not influence to big change of polyurethane resin properties. As test of tensile strength, DPU had highest tensile characteristic($3.114kg_f/mm^2$) and DPU-AD3 had lowest tensile characteristic($2.510kg_f/mm^2$). As same as tensile characteristic, abrasion test determined DPU(50.5 mg.loss) had highest properties. In elongation case, DPU had best properties(602 %) in this experiment.

Antioxidant, Antimicrobial and Anti-inflammatory Activities of Essential Oil from Erigeron annuus L. Flower (개망초꽃 에센셜 오일의 항산화, 항균 및 항염 활성)

  • Yi, Mi-Ran;Jeon, Ah-Lim;Kang, Chang-Hee;Bu, Hee-Jung
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.4
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    • pp.717-725
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    • 2016
  • This study was designed to examine the in vitro antioxidant, antimicrobial and anti-inflammation effects of essential oils of Erigeron annuus L. Flower. Erigeron annuus L. essential oils were obtained by solvent extraction. Antioxidative ability was evaluated by bioassays using ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) radical scavenging effect and 2, 2-diphenyl-1-1-picrydrazyl (DPPH) free radical scavenging activity. Erigeron annuus L. essential oil exhibited free radical scavenging activity on ABTS and DPPH 98.6%, 48.3% respectively, at a concentration of $500{\mu}g/ml$. Antimicrobial activity of essential oils of Erigeron annuus L. were tested against Staphylococcus aureus (S. aureus), Propionibacterium acnes (P. acne) and Escherichia coli (E. coli) by paper disc method, MIC and MBC. Erigeron annuus L. essential oil showed excellent antibacterial activities against S. aureus with MIC and MBC values of 0.31 mg/mL. The clear zone, indicating antimicrobial activity against P. acnes, was 14 mm, MIC and MBC values 0.31 mg/mL, 0.63 mg/mL, respectively. For the anti-inflammatory activity in RAW 264.7 cell, the Erigeron annuus L. essential oils inhibited not only NO production but also the expression of pro-inflammatory cytokines such as, TNF-${\alpha}$, IL-6 in a dose-dependent manner. These results suggested that Erigeron annuus L. essential oils has considerable potential as a cosmetic ingredient with antioxidative, antimicrobial and anti-inflammation effects.

Antimicrobial Activity of Rhus javanica Extracts Against Animal Husbandry Disease-Related Bacteria (가축질병 균주에 대한 오배자 추출물의 항균활성)

  • Choi, Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.8
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    • pp.1214-1220
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    • 2003
  • Antimicrobial activity of Rhus javanica (RJ) extract against animal husbandry disease-related bacteria was determined by a paper disc method. The RJ extracts showed a significant antimicrobial activity against Gram positive (+) bacteria and especially the activity was most potent against L. monocytogenes and S. epidermidis. Minimum inhibitory concentrations (MIC) of the MeOH and EtOH extracts of RJ were in the range of 0.8 ∼ 16 mg/mL and 0.8 ∼ 10 mg/mL, respectively. Furthermore, among five solvent fractions (n-hexane, CHC1$_3$, EtOAc, n-BuOH and $H_2O$ frs.) from MeOH extract of RJ, the EtOAc fr. exhibited the most significant antimicrobial activity The antimicrobial activities of RJ extracts against most microbial strains were unstable by either heat treatment or acid treatment. The inhibitory effect of RJ extracts on microbial cell growth was further examined by the addition of 0, 100, 300, and 500 ppm of RJ extracts into growth medium. The growth of gram positive (+) bacteria, S. aureus, S. epidermidis and L. monocytogenes was inhibited for 72 hours when at least 300 ppm of RJ extracts added, but the growth of gram negative (-) bacteria was only inhibited when at least 500 ppm of RJ extracts were added. Taken together, tile antimicrobial activities of RJ extracts were more effective against gram positive (+) bacteria compared to those against gram negative (-) bacteria.

Antioxidant and Antigenotoxic Activities of Extracts from Anglerfish (아귀 추출물의 항산화 및 항유전독성 활성)

  • Lee, Suck-Hee;Shin, Jin-Hwa;Koo, Myoung-O;Jung, Eun-Sil;Jeon, Geong-Im;Park, Eun-Ju;Park, Hae-Ryong;Lee, Seung-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.10
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    • pp.1229-1234
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    • 2007
  • Antioxidant activities of extracts from anglerfish (Lophiiu Zitulon) were evaluated. Each part of fresh (skin, flesh, stomach, and liver) or dried (skin and flesh) anglerfish was extracted by four different solvents (methanol, ethanol, acetone, and distilled water). Antioxidant activities of the extracts were determined by radical scavenging activity (RSA) and reducing power (RP). Relatively higher RSA and RP were found in methanol and water extract of fresh anglerfish liver. Antigenotoxic effect of the extracts, which was measured by Comet assay, was shown in most of the extracts except methanol, acetone and distilled water extracts of fresh stomach sample. These results indicated that antioxidant and antigenotoxic properties of extracts from angler fish were variable depending on parts, solvent, and/or physicochemical state. The appropriate extraction process could provide some valuable bioactive materials from anglerfish.

Antioxidant and Antihypertensive Activities of Styela plicata according to Harvesting Time and Size (채취시기와 크기에 따른 주름 미더덕의 항산화 및 항고혈압 활성)

  • Park, Ji-Won;You, Dong-Hyun;Bae, Myung-Suk;Kim, Jung-Mi;Lee, Jong-Hwa;Kim, Suk-Ju;Jeon, Yuo-Jin;Park, Eun-Ju;Lee, Seung-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.3
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    • pp.350-356
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    • 2011
  • Styela plicata of large (9.82~11.66 g) and small (0.93~2.21 g) sizes harvested at different times was extracted with 4 different solvents (methanol, ethanol, acetone, and water). DPPH radical scavenging and reducing power was the highest in acetone extracts of small ones (38.98% and 1.724, respectively) harvested in November. The lowest radical scavenging activity was found in water extracts of large ones (12.03% and 0.114) in December. On the other hand, large ones harvested in September showed significantly higher inhibition rate of DNA damage (water, 56.54%; methanol, 55.83%; ethanol, 48.63%) than others. Overall, the water extraction of S. plicata tended to show a higher antigenotoxic effect. In addition, water extracts of large S. plicata from November showed the highest angiotensin converting enzyme (ACE) inhibitory activity (64.38%), while that of small ones from December exhibited the lowest (51.33%). Overall the results indicate that antioxidant and antihypertensive activities S. plicata are variable depending on harvesting time, size, and extraction solvent.

Synthesis and Magnetic Properties of Nanosized Ce-substituted Yttrium Iron Garnet Powder Prepared by Sol-gel Method (졸-겔법에 의한 Cerium 치환 Nanosize YIG 분말의 합성 및 자기적 특성)

  • 장학진;김광석;윤석영;김태옥
    • Journal of the Korean Ceramic Society
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    • v.38 no.11
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    • pp.1008-1014
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    • 2001
  • Nanosize YIG powders added by Cerium which is exellent element in magneto-optical effect were synthesized by Sol-Gel method using Ethylene Glycol solvent. In 120 to 150 minute reaction time, stable sol solution which showed no change in viscosity, pH, and aging time was obtained. Monolithic YIG was synthesized at 80$0^{\circ}C$ with DTA and XRD measurement and its lattice parameter had a tendency to increase from 12.3921 $\AA$. Increasing annealing temperature from 80$0^{\circ}C$ to 105$0^{\circ}C$, average particle size was in the range of 40 nm to 330 nm. Saturation magnetization (M$_{s}$) value was increased from 18.37 to 21.25 emu/g due to enhancement of YIG crystallity and decreasing of orthoferrite phase. On the other hand, coercivity (H$_{c}$) value increased up to 90$0^{\circ}C$ and then decreased above 90$0^{\circ}C$. With increasing Ce addition, coercivity was almost not changed but saturation magnetization value was maximum at Ce 0.1 mol% and then decreased because of increasing a orthoferrite amount. Also, curie temperature (T$_{c}$) of YIG were not changed with Ce addition.ion.

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Screening of Antimicrobial Activity for Medicinal Herb Extracts (한약재 추출물의 항균효과 검색)

  • Park, Uk-Yeon;Chang, Dong-Suck;Cho, Hak-Rae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.21 no.1
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    • pp.91-96
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    • 1992
  • Twenty kinds of medicinal herbs were extracted by water and 95% ethanol and then antimicrobial activity of the extracts was investigated against various kinds of microorganisms. Water extracts of Gardeniae fructus (Gardenia jasminoides), Lycii fructus (Lycium chinense) and Schizandrae fructus (Schizandra chinensis) showed inhibitory effects on the growth of most of the bacteria. In the case of ethanol extracts, the 3 kinds of the samples such as Gardeniae fructus, Schizandrae fructus and Lithospermi radix (Lithospermum erythrorhizon) showed inhibitory effects on the growth of almost all bacteria. In particular, ethanol extract from Phellodendri cortex (Phellodendron amurense) showed the best inhibitory effect on the growth of S. aureus in the concentration of 0.01%. By the way, inhibitory effects of water extracts from these medicinal herbs were not so good on the growth of fungi but those of ethanol extracts were better and ethanol extracts of Phellodendri cortex showed best. Antimicrobial activity was variable according to the used extracting solvent. For example, inhibitory effets of ethanol ext-racts were $2{\sim}100$ times better than those of water extracts. Ethanol extract of Lithospermi radix was the most effective not only bactericidal effects but also sensory evaluation tests for tastes.

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Physiological Activities of Gardeniae Fructus Extracts by Microwave-Assisted Extraction as Affected by Solvents (마이크로웨이브로 추출한 용매별 치자(Gardeniae Fructus) 추출물의 생리활성)

  • Jeong, Hyun-Jin;Kim, Sun-A;Kwon, Joong-Ho;Kim, Hyun-Ku
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.3
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    • pp.282-287
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    • 2008
  • Gardeniae Fructus (GF) is a fruit of Gardenia jasminoides Ellis (Rubiaceae) which has been used in traditional medicine. It contains not only geniposide but also resveratrol, a kind of stilbene as a natural antioxidant. In this study, we investigated physiological activities of GF extracts by measuring electron donating ability (EDA), nitrite scavenging ability (NSA), super oxide dismutase (SOD)-like activity and inhibitory effect of tyrosinase activity (ITA). As a solvent, it was extracted with water, 50 and 100% ethanol using microwave. At the concentration of 6 mg/mL, EDA was the highest at 50% ethanol extract but the lowest at 100% ethanol extract, $96.43{\pm}0.25%\;and\;77.06{\pm}0.22%$ respectively. NSA showed the strongest activity at 50% ethanol extract like EDA (6 mg/mL: $75.26{\pm}0.28%$). ITAs were below 20% in all samples and their activities reduced according to increasing concentration. Likewise, SOD-like activities decreased with increasing concentration of extracts in all samples. In conclusion, GF extracts showed low SOD-like activities and ITAs but EDAs and NSAs were fairly high; especially EDA of 50% ethanol extract (6 mg/mL) was high as those of 0.1 and 1% L-ascorbic acid. Therefore the results suggest that GF extracts may be useful as potential sources of natural antioxidants.