• 제목/요약/키워드: natural medium

검색결과 1,272건 처리시간 0.025초

현행수의의 실태 및 문제점 (The Actual Condition and Problems of Current Shrouds)

  • 조효숙;안지원
    • 복식
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    • 제52권3호
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    • pp.123-137
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    • 2002
  • The purpose of this study is to analyze the actual condition and problems of current ready-made shrouds. Current shrouds were formed after the 20th century and therefore are quite apart from its traditional precedents of Chosun Dynasty. In this respect, several problems can be pointed out. 1. The use of natural colored hemp as a primary textile of current shrouds is far from our tradition. Silk, ramie, and cotton have to be used together with hemp. Also, more variety of colors can be used other than natural white. 2. The size of ready-made shrouds has to be categorized at least into three: large, medium and small 3. The pattern and sowing method of Dopo(도포) and Wonsam(원삼) should be corrected in line with those of the traditional Dopo(도포) and Wonsam(원삼). 4. The design and items of current ready-made shrouds have to break away from the standardized convention and should seek more of a variety that our rich tradition provide. 5. The rational index should be suggested so that consumers can compared the quality and price of ready-made shrouds available at their hands.

Role of Unstable Phenanthrene-Degrading Pseudomonas species in Natural Attenuation of Phenanthrene-Contaminated Site

  • Prakash, Om;Lal, Rup
    • 한국미생물·생명공학회지
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    • 제41권1호
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    • pp.79-87
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    • 2013
  • An unstable yet efficient phenanthrene-degrading bacterium strain Ph-3 was isolated from a petroleum-contaminated site at the Mathura Oil Refinery, India. The strain was identified as Pseudomonas sp. using a polyphasic approach. An analysis of the intermediates and assays of the degradative enzymes from a crude extract of phenanthrene-grown cells showed a novel and previously unreported pattern of 1, 2-dihydroxy naphthalene and salicylic acid production. While strain Ph-3 lost its phenanthrene- degrading potential during successive transfers on a rich medium, it maintained this trait in oligotrophic soil conditions under the stress of the pollutant and degraded phenanthrene efficiently in soil microcosms. Although the maintenance and in vitro study of unstable phenotypes are difficult and such strains are often missed during isolation, purification, and screening, these bacteria constitute a substantial fraction of the microbial community at contaminated sites and play an important role in pollutant degradation during biostimulation or monitored natural attenuation.

Effect of 2-NBDG, a Fluorescent Derivative of Glucose, on Microbial Cell Growth

  • Shin, Dong-Sun;Oh, Ki-Bong
    • Journal of Microbiology and Biotechnology
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    • 제12권5호
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    • pp.834-837
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    • 2002
  • A fluorescent glucose analogue,2-[N-(7-nitrobenz-2-ox a-1,3-diazol-4-yl) amino] -2- deoxy-D-glucose (2-NBDG), which had previously been developed for the analysis of glucose uptake in living cells, was investigated to determine its biological activity on microorganisms.2-NBDG did not show any inhibitory effect on growth of yeast cells and bacteria. In contrast, 2-NBDG exhibited strong inhibitory effects on filamentous fungal growth. The growth of filamentous fungi was completely inhibited, when 2-NBDG was supplemented as sole carbon source. The inhibitory effect was decreased by the addition of glucose in the test medium. Furthermore, 2-NBDC inhibited chitinase activity of Trichoderma sp. These results suggested that the inhibitory effects of 2-NBDG on filamentous fungi might be partially due to the inhibition of chitinase.

대수층 축열시스템의 열거동에 관한 실험적 연구 (An Experimental Study on the Thermal Behavior of Aquifer Thermal Energy Storage System)

  • 이세균;문병수;남승백;김기덕
    • 대한기계학회논문집
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    • 제16권9호
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    • pp.1780-1787
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    • 1992
  • 본 연구에서는 대수층을 시뮬레이션한 실험장치를 통하여 온도분포를 관찰하 고 자연대류에 관한 단순화된 이론적 모델을 개발하여 실험치와 비교 검토하고자 한 다.

음성과 데이터의 통합트래픽에 대한 Expressnet과 FDDI의 성능비교 (Performance Comparison between Expressnet and FDDI for intergrated Voice and Data Traffic)

  • 주기호
    • 자연과학논문집
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    • 제8권2호
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    • pp.93-99
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    • 1996
  • 이 연구에서는 음성과 데이터가 통합된 트래픽에 대하여 Expressnet과 FDDI의 성능을 비교하였다. 모든 시뮬레이션 결과에서 FDDI가 더 많은 음성 스테이션을 지원하는 것으로 나타났다. Expressnet에 비하여, FDDI가 파일전송형 데이타 트래픽에 대하여 높은 throughput을 보였으나 대화형 트래픽에 대해서는 긴 지연 시간을 보였다.

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Saponins from the Callus Mass of Phytolacca americana

  • Chi, Hyung-Joon;Kim, Hyun-Soo
    • Archives of Pharmacal Research
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    • 제8권1호
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    • pp.15-20
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    • 1985
  • Strong anti-inflammatory saponins Phytolacca americana (Phytolaccaceae) wereobtained from callus mass derived from the stems and also from that derived from the roots of cultivated Phytolacca americana (which were designated as PAS and PAR, respectively). The callus were grown on Linsmair and Skoog's agar medium supplemented with 1ppm OF 2, 4-dichlorophenoxyacetic acid. Phytol accoside B and D were obtained from PAS and phytolaccoside A and B from PAR. The thin layer chromatograms of the crude saponins from PAS and PAR were similar to those of original plants. PAS contained phytolaccoside B as a major component while phytolaccoside E was a major saponin in original plants.

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Vibration analysis of steel frames with semi-rigid connections on an elastic foundation

  • Vu, Anh Q.;Leon, Roberto T.
    • Steel and Composite Structures
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    • 제8권4호
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    • pp.265-280
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    • 2008
  • An investigation on the combined effect of foundation type, foundation flexibility, axial load and PR (semi-rigid) connections on the natural frequencies of steel frames is presented. These effects were investigated using a suitable modified FE program for cases where the foundation flexibility, foundation connectivity, and semi-rigid connections could be treated as equivalent linear springs. The effect of axial load on the natural frequency of a structure was found to be significant for slender structures subjected to high axial loads. In general, if columns of medium slenderness are designed without consideration of axial load effects, the frequency of the structure will be overestimated. Studies on the 3-story Los Angeles PR SAC frame indicate that the assumption of rigid connections at beam-column and column-base interfaces, as well as the assumption of a rigid foundation, can lead to significant errors if simplified design procedures are used. These errors in an equivalent static analysis are expected to lead to even more serious problems when considering the effect of higher modes under a non-linear dynamic analysis.

노화 매질과 충진 시스템이 천연고무 복합체의 회복 거동에 미치는 영향 (Influence of Aging Media and Filler System on Recovery Behaviors of Natural Rubber Composites)

  • 최성신;김옥배
    • Elastomers and Composites
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    • 제47권2호
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    • pp.156-161
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    • 2012
  • 공기와 증류수에서 노화시킨 천연고무 복합체의 원형 변형으로부터의 회복 거동의 차이를 연구하였다. 공기에서 노화시킨 시험편의 회복률이 증류수에서 노화시킨 것보다 더 컸다. 충진제로 보강한 시험편의 회복속도가 비충진 시험편보다 더 빨랐다. 카본블랙으로 보강한 시험편의 회복속도가 실리카로 보강한 시험편보다 더 빨랐다. 노화 매질에 따른 회복 거동의 차이는 가교밀도 변화와 아닐링 효과로 설명하였다.

연안환경 모니터링을 위한 홍합(Mytilus coruscus)의 체내 수은 함량 분석 (Determination of Mercury in Korean Mussels (Mytilus coruscus) for Marine Environmental Monitoring)

  • 이수용;이장호
    • 한국환경과학회지
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    • 제27권12호
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    • pp.1291-1298
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    • 2018
  • Marine ecosystems are frequently exposed to a variety of chronic and acute pollutants derived from anthropogenic production and consumption activities. Mussels are sessile (can provide location-specific information), medium-sized (have enough tissue matrix for chemical analysis) filter-feeders (show accumulation of pollutant chemicals from seawater). These biological and ecological characteristics make mussels virtually ideal for pollution monitoring. In this study, Korean mussels (Mytilus coruscus) were collected from nine different sites situated along the coasts of the western sea to the eastern sea of Korea in 2017. Total mercury concentration was highest (mean ${\pm}$ standard error, $92.7{\pm}3.5ng/g\;dry$) on Baengnyeongdo Island in the western sea, and the sites in the southern sea showed the lowest mean concentrations (42.3 - 44.5 ng/g dry). These results were discussed in terms of possible pollution sources.

Nonlocal thermal vibrations of embedded nanoplates in a viscoelastic medium

  • Zenkour, Ashraf M.
    • Structural Engineering and Mechanics
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    • 제82권6호
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    • pp.701-711
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    • 2022
  • The nonlocal elasticity as well as Mindlin's first-order shear deformation plate theory are proposed to investigate thermal vibrational of a nanoplate placing on a three-factor foundation. The Winkler-Pasternak elastic foundation is connected with the viscous damping to obtain the present three-parameter viscoelastic model. Differential equations of motion are derived and resolved for simply-supported nanoplates to get their natural frequencies. The influences of the nonlocal index, viscous damping index, and temperature changes are investigated. A comparison example is dictated to validate the precision of present results. Effects of other factors such as aspect ratio, mode numbers, and foundation parameters are discussed carefully for the vibration problem. Additional thermal vibration results of nanoplates resting on the viscoelastic foundation are presented for comparisons with future investigations.