• 제목/요약/키워드: Phenolic

검색결과 3,511건 처리시간 0.037초

항공우주용 리오셀계 탄소/페놀릭 복합재료의 내열 성능 평가 (Evaluation of Heat Resistance of Lyocell-based Carbon/Phenolic for Aerospace)

  • 서상규;김연철;배지열;함희철;황태경
    • 한국항공우주학회지
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    • 제49권5호
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    • pp.355-363
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    • 2021
  • 리오셀계 탄소/페놀릭 복합재료의 항공우주용 내열 부품 적용 가능성을 확인하기 위하여 내열성능 평가 및 열 해석을 수행하였다. 탄소/페놀릭의 열반응 평가는 내열성능평가모터(Thermal Protection Evaluation Motor, TPEM)로 수행되었다. 본 논문에서는 열 해석을 위해 유체의 경계층 해석을 고려한 경계층 적분 코드와 삭마 및 열분해를 고려한 MSC-Marc 2018 코드를 사용하였다. 추진기관의 압력 곡선, 연소 시험 후 절개된 목삽입재 시편을 통하여 삭마 및 단열성능을 분석하였고, 리오셀계 탄소/페놀릭 복합재료의 열반응은 레이온계 탄소/페놀릭 재료와 유사하였다. 연소시험을 통한 결과를 바탕으로 국산 리오셀계 탄소/페놀릭의 항공우주용 내열 부품으로의 적용 가능성을 확인하였다.

계절 변화에 따른 한국산 가시오가피 줄기의 페놀성 성분 함량 분석 (Seasonal Variation of Phenolic Component Contents in the Stems of Korean Acanthopanax senticosus)

  • 김도형;고성권;양병욱
    • 한방비만학회지
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    • 제23권1호
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    • pp.10-17
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    • 2023
  • Objectives: The aim of this study was to compare the total phenolic content of Korean Acanthopanax senticosus stems harvested in different seasons and provide basic data for developing functional reinforcement products based on the optimal harvesting time. Methods: Each sample harvested in different seasons was extracted and concentrated twice for 2 hours using 70% ethyl alcohol. Phenolic compounds were analyzed using high-performance liquid chromatography for simultaneous multi-component analysis of 14 compounds, including syringaresinol and so on. Results: The results showed that the stem of Korean Acanthopanax senticosus harvested in winter (November 29th) (EAS-5) had the highest phenolic content of 1.038%. The stem of Korean Acanthopanax senticosus harvested in autumn (October 1st) (EAS-4) showed the second-highest phenolic content of 0.764%, followed by the stem of Korean Acanthopanax senticosus harvested in spring (February 2nd) (EAS-1) with a content of 0.390%. On the other hand, the stem of Korean Acanthopanax senticosus harvested in the summer (June 2nd) (EAS-3) showed the lowest content at 0.342%. In conclusion, the stem of Korean Acanthopanax senticosus harvested in winter (EAS-5) showed the highest phenolic compound content. Conclusions: Considering the extraction yield and the total phenolic content, as well as the concentrations of key functional components such as eleutheroside B, chlorogenic acid, and syringaresinol in the 70% ethyl alcohol extract of Korean Acanthopanax senticosus, it is suggested that the stems of Korean Acanthopanax senticosus harvested during the winter season are suitable for the development of novel materials with enhanced anti-obesity functionality.

Two Phenolic Amides from Cocculus diversifolius

  • Kim, Youn-Chul;Kingston, David G.I
    • 생약학회지
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    • 제26권3호
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    • pp.273-275
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    • 1995
  • Two phenolic amides were isolated from the stem of Cocculus diversifolius (Menispermaceae) and identified as N-trans-feruloyl tyramine and N-trans-feruloyl 3-methyldopamine by spectroscopic methods.

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담배연기 응축물중 phenolic fraction의 분리와 확인 (The Identification & Separation of Phenolic fraction in Cigarette Smoke Condensate)

  • 이문수;임흥빈;장기철
    • 한국연초학회지
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    • 제10권1호
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    • pp.49-57
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    • 1988
  • The phenolic compounds were isolated from the cigarette smoke condensate using two immiscible organic solvents by a partition coefficient. Of them, 20 phenolic compounds were identified by GC and GC/MS. The amount of the phenolic compounds was phenol, p-crestol, hydroxybensoic acid in order. And there was no difference in composition of these compound dependent on leaf tobacco . About 70% amount of these compounds were absorbed to cellulose acetate filter used. The contents and composition of these compounds were various in the commercial cigarette.

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흡착관/열탈착 GC/MS 방법에 의한 모사시료 중의 미량 페놀 분석에 관한 평가 (Evaluation of the Measurement of Trace Phenols by Adsorption/Thermal Desorption/Gas Chromatography/Mass Spectrometry (ATD/GC/MS) in Artificial Air)

  • 허귀석;이재환;황승만;정필갑;유연미;김정우;이대우
    • 한국대기환경학회지
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    • 제18권2호
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    • pp.127-137
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    • 2002
  • Phenolic compounds in air are toxic even at their low concentrations. We had evaluated a total of five phenolic compounds (Phenol, o-Cresol, m-Cresol, 2-Nitrophenol and 4-Chloro-3-methylphenol) in artificial air using a combination of ATD/GC/MS. To compare the adsorption efficiency of these phenolic compounds, three adsorbents (Tenax TA, Carbotrap and Carbopack B) were tested. Tenax TA adsorbent was most effective of all the adsorbents used for the efficiency test. Five phenolic compounds were found to be very stable on adsorbent tubes for 4 days at room temperature. Detection limit of five phenolic compounds ranged from 0.05 to 0.08 ppb (when assumed to collect 10 L air). The calibration curve was linear over the range of 22∼ 164 ng. The reproducibility was less than 4%. Sampling of duplicate pairs (DPs) was made to demonstrate duplicate precision and sampling efficiency.

Phenolic Acid Changes in Mycelia of Sclerotium rolfsii After Garlic and Onion Supplementation in a Broth Medium

  • Pandey, M.K.;Singh, D.P.;Singh, U.P.
    • Mycobiology
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    • 제33권3호
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    • pp.137-141
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    • 2005
  • High performance liquid chromatographic (HPLC) analysis of mycelia of Sclerotium rolfsii grown in broth medium supplemented with garlic (Allium sativum) and onion (Allium cepa) was carried out to estimate qualitative and quantitative changes in phenolic acids. Several phenolic acids, such as gallic, chlorogenic; ferulic, o-coumaric and cinnamic acids were detected in varied amounts in mycelia grown on such media as compared to control. Phenolic acids represents a wide range of secondary metabolite found in the cells of plants and microbes including fungi. The growth characters of S. rolfsii in various supplements also varied from thin and transparent to thick and opaque.

한국산 Agrobacterium tumefaciens KU12so Ti-plasmid의 vir 유전자 발현 유도 물질 (Inducers for the vir Gene Expression of Ti-Plasmid in Korean Agrobacterium tumefaciens KU12)

  • 김준영
    • Journal of Plant Biology
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    • 제34권3호
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    • pp.245-251
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    • 1991
  • In order to investigate the phenolic compounds inducing the expression of Ti-plasmid vir genes of Agrobacterium tumefaciens KU12, we tested whether the eighteen phenolic compounds known as vir gene inducer have the activity to induce vir operon of the Ti-plasmid in A. tumefaciens KU12 transformed with pSM358cd. Also, the phenolic compounds in some tumor-uninduced dicotyledons and the attachment ability of a. tumefaciens KU12 on such dicotyledonous plants were investigated in an effort to analyze the reason why no tumor is formed on the plants. As results, fifteen among eighteen phenolic compounds known as vir gene inducer induced the expression of the Ti-plasmid vir genes. Some dicotyledonous plants which do not form the tumor have the phenolic compounds inducing the vir genes, but have less ability of the attachment than the dicotyledonous plants forming tumor.

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탄소/페놀 하이브리드 복합재료의 역학적 특성 및 열적 특성에 관한 연구 (On the Mechanical and Thermal Properties of Carbon/Phenolic Interply Hybrid Composite)

  • 신승준;박종규;강태진;정관수
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
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    • pp.29-32
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    • 2002
  • The mechanical and thermal properties of spun carbon fabric/continuous carbon fabric interplay hybrid composite materials have been studied. The properties of the hybrid composites are compared with those of the continuous carbon fabric/phenolic composites and spun carbon fabric /phenolic composites. Through hybridization, tensile strength and flexural strength of hybrid composites were increased by about 17%, and 10%, respectively compared with spun carbon composites. The thermal conductivity of the hybrid composite is lower approximately 4~6% along the direction parallel to the laminar plane than that of the continuous carbon/phenolic composite.

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Regulation of Phycocyanin Development by Phenolic Compounds in the Cyanobacterium Anabaena sp. PCC 7120

  • Kim, Jin-Yong;Jo, Yeara;Kim, Young-Saeng;Lee, Eun-Jin;Yoon, Ho-Sung
    • 생태와환경
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    • 제39권4호통권118호
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    • pp.445-449
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    • 2006
  • Phenolic compounds are manufacturing by-products commonly found in industrial wastewater. The toxicity of high level phenolic compounds in wastewater threatens not only the aquatic organisms, but also many components of the adjacent ecosystem. One of the major light harvesting pigments in cyanobacteria is phycocyanin which can be rapidly and specifically degraded by external stimuli such as nutritional depletion or environmental stress. We employed the cyanobacterium Anabaena sp. PCC 7120 as an indicator organism in estimating the pollution level by phenolic compounds. The phycocyanin content of the cyanobacterium decreased without significantly altering the total chlorophyll as the phenol concentration in a medium increased. We examined the phenol contamination level using the correlation of the phycocyanin content and the phenol concentration. Our results indicated that no significant pollution by phenolic compounds was found in several waterbodies in the vicinity of Daegu, South Korea.