• 제목/요약/키워드: Organic media

검색결과 694건 처리시간 0.03초

다양한 계면활성제를 이용한 고순도 단일벽 탄소나노튜브의 수계 분산 (Dispersion of Highly Pure Single-Walled Carbon Nanotube in Aqueous Solution of Various Surfactants)

  • 곽정춘;김명수;이내성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.153-153
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    • 2008
  • Practical application of single-walled carbon nanotubes (SWCNTs) qualified as a promising material has been limited by either poor dispersion or their insolubility in aqueous or organic media due to formation of bundling by relatively high surface energy. Thus, major attention to overcome this issue has been paid at surface modification of CNTs by functionalization, but this introduces defects to the sidewall of CNTs, consequently perturbing the inherent electronic and optical properties. Therefore, using surfactants is a general approach to disperse SWCNTs with lower damages by which bundled nanotubes could be dispersed up to the level of individuals or small bundles. Here, we have investigated various surfactants for their efficiency in dissolving purified SWCNTs produced by arc discharge in deionized water. To compare the surfactants respectively, we have determined the least amount of each surfactant to suspend the nanotubes under optimized experimental conditions(CNT amount, sonication power, and centrifugation speed, etc.) set on the basis of the most common surfactant (sodium dodecyl sulfate, SDS) and discussed the qualitative and quantitative characterization of SWCNT dispersions by UV-Vis absorption spectroscopy. Quantitative aspect about nanotube dispersion was that in particular N-methyl-2-pyrrolidone (NMP) and sodium dodecylbenzene sulfonate (NaDDBS) were found to be effective in dispersing individual tubes.

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Culture Conditions for the Mycelial Growth of Ganoderma applanatum

  • Jo, Woo-Sik;Cho, Yun-Ju;Cho, Doo-Hyun;Park, So-Deuk;Yoo, Young-Bok;Seok, Soon-Ja
    • Mycobiology
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    • 제37권2호
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    • pp.94-102
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    • 2009
  • Ganoderma applanatum is one of the most popular medicinal mushrooms due to the various biologically active components it produces. This study was conducted to obtain basic information regarding the mycelial culture conditions of Ganoderma applanatum. Based on the colony diameter and mycelial density, PDA, YMA and MCM media were suitable for the mycelial growth of the mushroom. The optimum temperature for mycelial growth was found to be $25{\sim}30^{\circ}C$. The optimum carbon and nitrogen sources were mannose and dextrin, respectively, and the optimum C/N ratio was 2 to 10 when 2% glucose was used. Other minor components required for the optimal growth included thiamine-HCl and biotin as vitamins, succinic acid and lactic acid as organic acids, and $MgSO_4$ $7H_2C$, $KH_2PO_4$ and NaCl as mineral salts.

울릉도 섬시호 자생지의 생태학적 특성 및 식물상 (Ecological Characteristics and Distribution of Bupleurum latissimum in Ulleung Island)

  • 안영희;이성제
    • 한국환경과학회지
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    • 제16권6호
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    • pp.751-761
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    • 2007
  • This study is carried out through ecological situation of native Bupleurum latissimum habitats and the research of environmental conditions for conservation of native sites, restoration of alternative habitats and preliminary data for application of useful medicinal plant. Native Bupleurum latissimum habitats were distributed on lower and middle part of the mountain from Altitude 54m to 185m, and the directions of slope were researched as usually northen and western slope. As a result of phytosociological research in 12 stands of native Bupleurum latissimum habitats, they were seperated to two communities(Bupleurum latissimum typical community and Bupleurum latissimum-Galium spurium community) in accordance with containable rate of the organic matter and soil hardeness. Soil condition is usually constituted as loamy sand and clay loam. Bupleurum latissimum is propagated in valuable soil conditions. Bupleurum latissimum lives with Morus bombycis, Reynoutria sachalinensis in Bupleurum latissimum typical community and Thalictrum aquilegifolium, Stellaria media, Hedera rhombea etc. is appeared with Bupleurum latissimum in Bupleurum latissimum-Galium spurium community. Especially, companion species were researched as Aster glehni, Dystaenia takeshimana and so on. The flora of vascular plants in this study is 44 families, 88genus 82species, 2 subspecies, 14 varietas, 4 forma and total 102 taxa. Plants of compositae occupied 10.78% among whole of them.

Retention Factors and Resolutions of Amino Benzoic Acid Isomers with Some Ionic Liquids

  • Zheng, Jinzhu;Polyakova, Yulia;Row, Kyung-Ho
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제11권6호
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    • pp.477-483
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    • 2006
  • Ionic liquids in the form of organic salts are being widely used as new solvent media. In this paper three positional isomers, o-amino benzoic acid, m-amino benzoic acid, and p-amino benzoic acids were separated with four different ionic liquids as mobile phase additives using high performance liquid chromatography (HPLC). The following ionic liquids were used: 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][$BF_{4}$]), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIm][$BF_{4}$]), 1-ethyl-3-methylimidazolium methylsulfate ([EMIm][MS]), and 1-octyl-3-methylimidazolium methylsulfate ([OMIm][MS]). The effects of the alkyl group length on the imidazolium ring and its counterion, and the concentrations of the ionic liquids on the retention factors and resolutions of amino benzoic acid isomers were tested. The results of the separations with ionic liquids as the eluents were better than those without ionic liquids. Excellent separations of the three isomers were achieved using 2.0-8.0 mM/L [OMIm][MS] and 1.0-8.0 mM/L [EMIm][MS] as the eluent modifiers.

인쇄산업의 변화와 친환경 인쇄 (The Changed of Graphic Arts Industry & Friendly Eco-Printing)

  • 하영백;이의수;오성상;구철회;윤종태
    • 한국인쇄학회지
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    • 제26권2호
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    • pp.79-89
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    • 2008
  • Eco printing offers the perfect balance between getting all our printing jobs done without endangering the environment. It is important to realize that the printing industry is no exception to this rampant destruction of the planet's natural resources. In fact, surprisingly enough, its effect on the environment is an extremely harmful one. Like most other production operations, printing houses also produce harmful waste products that pollute the air we breathe in. They also put a great drain on precious natural resources. Printing houses emit what are known as volatile organic compounds (VOCs), caused by the use of petroleum-based inks, laminates, varnishes and adhesives. Studies show that these compounds, when inhaled, greatly increase the risk of asthma attacks. Eco printing, however, has a larger scope than is apparent. Eco printing has a dual essence. In order to understand what it is really all about, the issue of conservation is no less important than the need to stop polluting the environment.

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디자인 호텔의 인터랙션디자인 속성 비교 연구 (Comparative Study on the Characteristics of Interaction Design in the Design Hotel)

  • 이미경
    • 한국실내디자인학회논문집
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    • 제19권1호
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    • pp.208-216
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    • 2010
  • The design hotel where new life styles of users were created and the exchange of one's identity and the culture was executed was employed the interaction design which considered the attendance and experience of users as the important motives. This study is to discuss on the relationship between the design hotel and interaction design, and to compare and analyze the differences in the expression methods of them. It was concluded that the design hotel had a close relation with the properties of information supply, amusements, narrative, personalization, and social exchange in the interaction design, and it mainly used the digital media of non-material, the juxtaposition of strangeness, the change of structure, substitution of values, appropriation of hybrid as a means of its expression. In addition, it was revealed that the properties above did not simply apply to an open space but were connected as a dominant-subordinate relationship into one subject. It is expected that the field of interaction design in the design hotel will be expanded due to the spread of digital technology and its role and importance will be increased. Therefore, it is thought that the study to provide the development of a variety of contents of design hotel should be kept through the study of organic relation between different subjects, avoiding the indiscriminate use of the contents.

2014 베니스 비엔날레 건축전 한국관의 전시이미지 표현특성 - 충돌 몽타주와 간격을 중심으로 - (Expressive Characteristics of Exhibition Image in 'The Korean peninsula' at the Venice Biennale Architecture 2014 - Focused on the Montage of Collision and Interval -)

  • 박영태
    • 한국실내디자인학회논문집
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    • 제26권1호
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    • pp.63-74
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    • 2017
  • This study is for the characteristic of expression of exhibition presentation in 'The Korean peninsula' which is the Golden Lion Winner at the Venice Biennale in 2014. The Korean peninsula provides two opposite political and economic systems and adaptations of modernism through various multi media images. The curator, Minsuk Cho, presented cinema montage image of Collision for analyzing dynamic exhibition organization and provides the foundation of his theory from Bergson's image and duration to Deleuze's movement-image and time-image which is mentioned from Deleuze's book "cinema 1" and "cinema 2". Furthermore, the Korean peninsula has showed perception-image and affection-image from Eisenstein & Vertov's cinemathology and systemized exhibition presentation. The montage of Collision has maximized the movement from the variety and complexity in a collision and it made difference between information images which are space, time, emotion, intelligence, the tumult between subjectivity and objectivity, fragments from reorganizing itself, and distribution and art images. The limit of montage of Collision's dialectic is not only visual but also space from organic organization but the Korean peninsula overcomes its limit and shows leap of tactile perception and time-reflection from the montage of Collision's dialectic. Therefore, the exhibition of the Korean peninsula presents the conviction of adaptations of modernism.

용액코팅된 탄소나노튜브 전극의 광전기적 성질 (Opto-electrical properties of solution based carbon nanotube electrode)

  • 우종석;김선영;한중탁;이건웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.394-394
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    • 2007
  • Transparent conductive films can serve as a critical component in displays, solar cells, lasers, optical communication devices, and solid state lighting. Carbon nanotube (CNT) based transparent conductive films are fabricated on glass and polymer substrates. CNTs typically exist in form of quasi-crystalline bundles or highly entangled bundles containing tens of individual nanotubes. To achieve full potential, CNTs must be dispersed in a solvent or other organic media. CNTs are acid treated with nitric acid then the stable dispersion of CNTs in polar solvent such as alcohols, DMF, etc. is achieved by sonication. The solubility of CNTs correlates well with the area ratio of the D and G bands from Raman spectrum. Thin films are formed from well dispersed CNT solutions using spray coating method. CNT thin films exhibit a sheet resistance ($R_s$) of nearby $10^3\;{\Omega}/sq$ with a transmittance of around 80% on the visible light range, which is attributed by excellent dispersion and interaction among CNTs, solvents and polymeric binders.

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Development of diverse fluorides source for applicable F-18 radiofluorination method

  • Park, Su Hong;Kim, Dong Wook
    • 대한방사성의약품학회지
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    • 제2권1호
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    • pp.17-21
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    • 2016
  • Alkali metal fluoride sources (MFs) such as potassium fluoride (KF) have been widely used as a fluoride source in the nucleophilic displacement reaction. However, they have low solubility and nucleophilicity in most of the organic solvents. Bulky fluoride sources such as tetrabutylammonium fluoride (TBAF) were substituted for MFs to improve these properties. However, hygroscopic property of TBAF makes it less convenient for handling as well as its strong basic property can make the side-reaction occur. Recently, novel fluoride sources have been developed to solve these problems. In this paper, we would like to introduce coordinated fluoride sources as a new fluoride sources such as tetrabutylammonium tetra(t-butyl alcohol)-coordinated fluoride, crown ether metal complex fluoride, and various bulky alcohols coordinated fluoride complexes. In particular, bulky alcohol coordinated fluoride source could generated by the controlled hydrogen-bonded of fluoride with alcohols and these fluoride sources have better stability and reactivity with showing low hygroscopic property. The study of these fluoride sources will help to understand the characteristic of [$^{18}F$]fluoride for increasing the radiochemical yield in the [$^{18}F$]radiofluorination.

지하수 흐름의 해석해를 이용한 토양진공추출 해석 (Analysis of Soil Vacuum Extraction using Analytical Solution of Groundwater Flow)

  • 김민환;이학;한동진
    • 한국방재학회 논문집
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    • 제9권5호
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    • pp.139-145
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    • 2009
  • 불포화지역의 유기화합물을 제거하기위해 지하수 흐름 해석해를 토양 진공추출 설계에 적용시켰다. 토양 공극 속의 가스 밀도가 압력에 따라 달라지므로 가스나 증기의 흐름을 지배하는 방정식은 비선형이다. 선행 연구자 의해 선형화된 방정식은 지하수 흐름의 지배방정식과 유사하다. 압력대수층과 누수대수층의 압력강하량에 대해서 Massmann의 자료를 이용하여 비교하였다. 압력대수층에 대해서는 Massmann에 의해 제시된 Theis의 해를 수정하였으며 Theis의 해를 검증하기 위해 GASSOLVE9의 프로그램을 이용하였다. Hantush의 해석해를 이용하여 누수대수층 구조에 대해서 압력 강하량을 계산하여 Massmann의 해와 비교하였다. 그 결과 압력강하량에 대해 근사적인 결과를 얻었다.