• Title/Summary/Keyword: 유기용매

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Relations between heat shock and oxidative stress to Ps. putida BCNU 171 and Micrococcus BCNU 121 by protein expression survey (유기용매 내성균주 Ps. putida BCNU 171과 Micrococcus sp. BCNU 121에서의 단백질 발현조사를 통한 heat shock 반응과 oxidative stress 반응의 유기용매내성과의 연관성)

  • Choe, Seung-Tae;Kim, Sun-Jeong;Lee, Ji-A;Bae, Gi-Jeong;Mun, Ja-Yeong;Lee, Ho-Won;Ju, U-Hong
    • Proceedings of the Korean Society of Life Science Conference
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    • 2001.09a
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    • pp.79-80
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    • 2001
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Effect of Organic Solvent-Modification on the Electrical Characteristics of the PCBM Thin-Film Transistors on Plastic substrate (플라스틱 기판상에 제작된 PCBM 박막 트랜지스터의 전기적 특성에 대한 유기 용매 최적화의 효과에 대한 연구)

  • Hyung, Gun-Woo;Lee, Ho-Won;Koo, Ja-Ryong;Lee, Seok-Jae;Kim, Young-Kwan
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.2
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    • pp.199-204
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    • 2012
  • Organic thin-film transistors (OTFTs) have received considerable attention because their potential applications for nano-scale thin-film structures have been widely researched for large-scale integration industries, such as semiconductors and displays. However, research in developing n-type materials and devices has been relatively shortage than developing p-type materials. Therefore, we report on the fabrication of top-contact [6,6]-phenyl-C61-butyricacidmethylester (PCBM) TFTs by using three different solvent, o-dichlorobenzene, toluene and chloroform. An appropriate choice of solvent shows that the electrical characteristics of PCBM TFTs can be improved. Moreover, our PCBM TFTs with the cross-linked Poly(4-vinylphenol) dielectric layer exhibits the most pronounced improvements in terms of the field-effect mobility (${\sim}0.034cm^2/Vs$) and the on/off current ratio (${\sim}1.3{\times}10^5$) for our results. From these results, it can be concluded that solvent-modification of an organic semiconductor in PCBM TFTs is useful and can be extended to further investigations on the PCBM TFTs having polymeric gate dielectrics. It is expected that process optimizations using solution-processing of organic semiconductor materials will allow the development of the n-type organic TFTs for low-cost electronics and various electronic applications.

Antioxidant Activities of Citrus unshiu Extracts obtained from Different Solvents (추출용매에 따른 진피 추출물의 항산화 활성)

  • Lee, Sung-Gu;Oh, Sung-Cheon;Jang, Jae-Seon
    • The Korean Journal of Food And Nutrition
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    • v.28 no.3
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    • pp.458-464
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    • 2015
  • In this study, the total polyphenol content, electron donating ability (EDA) and inhibitory activity of glutathione S-transferase (GST) of freeze-dried Citrus unshiu extracts were examined. The Citrus unshiu extracts was obtained from four solvents such as ethyl acetate, acetone, methyl chloride and methanol, to evaluate its functional properties. Total polyphenol contents were measured in the two different extracts, and the extracts were screened for their potential antioxidant activities using tests such as electron donating ability (EDA), glutathione S-transferase (GST). The total polyphenol contents of Citrus unshiu extracts were $928.48{\pm}1.19{\mu}g\;GAE/mL$ in ethyl acetate (EA), $886.03{\pm}0.44{\mu}g\;RE/mL$ in acetone (AC), $413.08{\pm}1.39{\mu}g\;GAE/mL$ in methylene chloride (MC), $12,648.60{\pm}0.56{\mu}g\;GAE/mL$ in methanol (MeOH), respectively. Also, the total polyphenol contents of EtOH Citrus unshiu extracts were $664.64{\pm}0.74{\mu}g\;GAE/mL$ in EA, $702.67{\pm}0.85{\mu}g\;RE/mL$ in AC, $429.64{\pm}0.61{\mu}g\;GAE/mL$ in MC, $16,108{\pm}0.73{\mu}g\;GAE/mL$ in MeOH, respectively. The total polyphenol contents were significantly difference (p<0.05) between the solvents. The electron donating ability of Citrus unshiu extracts were $62.80{\pm}0.36%$ in EA, $97.43{\pm}0.51%$ in AC, $52.20{\pm}0.30%$ in MC, $97.63{\pm}0.46%$ in MeOH, respectively. Also, the electron donating ability of EtOH Citrus unshiu extracts were $51.49{\pm}0.26%$ in EA, $63.17{\pm}0.31%$ in AC, $67.68{\pm}0.55%$ in MC, $96.18{\pm}0.41%$ in MA, respectively. The electron donating ability were significantly difference (p<0.05) between the solvents. The inhibitory activity of glutathione S-transferase in Citrus unshiu extracts were $76.22{\pm}0.65%$ in EA, $31.73{\pm}0.48%$ in MC, $97.48{\pm}0.56%$ in MeOH, respectively. Also, inhibitory activity of glutathione S-transferase in EtOH Citrus unshiu extracts were $75.54{\pm}0.55%$ in EA, $73.53{\pm}0.38%$ in MC, $48.70{\pm}0.46%$ in MeOH, respectively. The inhibitory activity of glutathione S-transferase were significantly difference (p<0.05) between the solvents. These results indicated that the Citrus unshiu extracts is a high-valued food ingredient and the extraction with methanol will be useful as a nutritional source with natural antioxidant activities. Considering high consumer demand beneficial health effects, Citrus unshiu extracts can be utilized to develop functional food health- promoting and natural antioxidant agents.

Changes of Sound Absorption Capability of Wood by Organosolv Pretreatment (유기용매 전처리에 의한 목재의 흡음성능 변화)

  • Kang, Chun-Won;Choi, In-Gyu;Gwak, Ki-Seob;Yeo, Hwan-Myeong;Lee, Nam-Ho;Kang, Ho-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.40 no.4
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    • pp.237-243
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    • 2012
  • Sound absorption capability and anatomical features of the organosolv pretreated Japanese larch and yellow poplar wood were estimated by stereoscopic observation and two microphone transfer function method. Sound absorption capabilities of organosolv treated wood, in the entire estimated frequency range (50~6,400 Hz), were higher than those of control specimen. Especially, the treated wood's absorption capabilities measured in the frequency range of 2~4 kHz were about two times higher than those of control specimen. By the organosolv pretreatment (at $70{\sim}120^{\circ}C$), the weight loss of wood occurred in less than 1% of total weight of wood and the porosity of wood increased slightly. In addition, it was presupposed that microstructural changes of wood occurred during organosolv pretreatment and this structural changes cause the increasing of the sound absorption capability of wood.

Antioxidant and Anti-Inflammatory Activities of Crude Extract and Solvent Fractions of Allium hookeri (삼채의 조추출물과 유기용매 분획물에 대한 항산화 및 항염증 효과)

  • Lee, Yong-Bum;Ham, Young-Min;Yoon, Seon-A;Oh, Dae-Ju;Song, Sang-Mok;Hong, In-Choel;Lee, Si Taek;Hyun, Ho Bong;Kim, Chang-Suk;Yoon, Weon-Jong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.1
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    • pp.18-25
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    • 2017
  • This study describes the preliminary evaluation of antioxidant and anti-inflammatory activities of Allium hookeri. A. hookeri was extracted using crude extract and then fractionated sequentially with n-hexane, $CH_2Cl_2$, EtOAc, and n-BuOH. To screen for antioxidant and anti-inflammatory agents effectively, we first examined the inhibitory effect of A. hookeri extracts on production of oxidant stresses (2,2-diphenyl-1-picrylhydrazyl, xanthine oxidase, and superoxide). In addition, we examined the inhibitory effects of A. hookeri on production of pro-inflammatory factors (nitric oxide, prostaglandin $E_2$, inducible nitric oxide synthase, and cyclooxygenase-2) in murine macrophage RAW 264.7 cells stimulated with lipopolysaccharide. Of the sequential solvent fractions of A. hookeri, EtOAc fractions showed decreased production of oxidant stresses, and $CH_2Cl_2$ and EtOAc fractions of A. hookeri inhibited production of pro-inflammatory factors. EtOAc fraction inhibited production of pro-inflammatory cytokines (interleukin-6 and -$1{\beta}$). These results suggest that A. hookeri has significant effects on oxidant stresses and pro-inflammatory factors and is a possible antioxidant and anti-inflammatory therapeutic and preventive material.

Antioxidant and Antimutagenic Activity of Solvent-Fractionated Layers of Colored Rice Bran (유색미 품종별 유기용매 추출물의 항산화성 및 항변이원성 검정)

  • Kang, Mi-Young;Shin, Soo-Young;Nam, Seok-Hyun
    • Korean Journal of Food Science and Technology
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    • v.35 no.5
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    • pp.951-958
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    • 2003
  • Twenty-four cultivars of colored rice seeds were collected inside and outside Korea, and the antioxidant and antimutagenic activity was determined for the solvent-fractionated layers of their bran parts lipid soluble fraction, pigment containing fraction, and pigment component per se. As the serial organic solvent extraction proceeded, the overall tendency of antioxidant activities declined with increased chemical homogeneity of each fraction. This markedly showed the low antioxidativities of the pigment components from LK 1-3-6-12-1-1 and Gillimhukmi. Even all the colored rice cultivars, with considerable antimutagenic activity in 70% ethanolic extract, exhibited mutagenicity when measured with its pigment containing fraction (wx 124-163-45-7-1-1-1 and LKlB-2-1-1 being the strongest). The pigment content in each colored rice seeds decreased in the order of IR 17491-5-4-3-3>LK 1-3-6-12-1-1>LK 1D-2-12-1>RGS No.336, Elwee. In addition, a substantial difference in both chemical composition of the constituents and its amount could be found between the colored rice and cooking rice cultivars. This revealed that, compared to cooking rice, major components of organic solvent fractions from colored rice probably have long hydrocarbon chain moieties.

Synthesis and Characterization of Sulfonated Polyetherimide

  • 김완주;전종영;탁태문
    • Proceedings of the Membrane Society of Korea Conference
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    • 1996.04a
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    • pp.42-43
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    • 1996
  • 고분자 분미막을 이용한 분리기술은 기존의 분리기술에 비하여 에너지의 절약과 높은 분리효율 등의 장점이 있어 거의 모든 산업에 이용되고 있다. 분리막의 용도가 다양화됨에 따라서 내열성, 내약품성, 내유기용매성을 갖는 막소재의 개발이 필요하게 되었다. polyimide(PI)게의 고분자는 물리, 화학적 성능이 우수하고 내열성과 내유기용매성 등이 우수한 열가소성수지로서 film, sheet, tubular형으로 만들 수 있어 한외여과막이나 역삼투막, 기체분리막 등에 이용되고 있다. 그러나 투과속도를 높디고, fouling을 줄이기 위해서는 화학적 개질을 통해 친수성을 높이는 방법이 필요하다. 본 실험에서는 내열성과 내유기용매성이 우수한 polyetherimide계 고분자를 chlorosulfonic acid(CSA)를 이용하여 술폰화시킴으로써, 극성기의 도입에 의해 친수성이 향상된 sulfonated polyetherimide(SPEI)를 합성하였다.

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The Structure of Ligand, N-benzylisonitrosoacetylacetone Imine (리간드 N-Benzylisonitrosoacetylacetone Imine의 구조)

  • Byung Kyo Lee;Dae Sub O;Heung Lark Lee
    • Journal of the Korean Chemical Society
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    • v.32 no.6
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    • pp.549-556
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    • 1988
  • In order to study the changes for the structure of N-benzylisonitrosoacetylacetone imine synthesized already in organic solution, nmr and carbon-13nmr DEPT spectra of the this reagent have been studied. Based on the present studies, it is suggested that this reagent is monoxime having syn- and anti-form isomers and has tautomers in solution respectively.

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