• 제목/요약/키워드: molecular gas

검색결과 868건 처리시간 0.022초

$SF_{6}$-Ar혼합가스에서의 압력 의존도 해석 (The analysis of dependence on the gas number density in $SF_{6}$-Ar mixtures)

  • 전병훈;하성철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집
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    • pp.248-251
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    • 2002
  • We measured the electron drift velocity, W, in 0.5% $SF_{6}$-Ar mixture over the E/N range from 30 Td to 300 Td and gas pressure range from 0.1 to 8 Torr by the double shutter drift tube with a variable drift distance. This coefficient in the mixture was calculated over the same E/N and gas pressure range by using the two-term approximation of the Boltzmann equation. And the measured and calculated values at different gas number density at each E/N was appreciable dependence in the results on the gas number density,

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Langmuir-Blodgett 초박막의 gas 센서 특성 (Characteristics of Gas Sensor in Langmuir-Blodgett Ultrathin Films)

  • 최용성;김철홍;장상목;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1992년도 추계학술대회 논문집
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    • pp.55-58
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    • 1992
  • It was attempted to investigate the reaction of LB biological membrane in the gas surrounding by the use of LB method. The performance of the experiment was based on the idea that the adhesion of gas molecular on the surface of LB membrane, which induces the change of electrical properties, may make it possible to develop various sensor system modified from the sensor organs. The experimental results showed that for the acetone gas, the frequency changes in the proportional to the concentration of the gas. The reappearance of the gas reaction vs. frequency change was also able to be obtained properly.

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OBSERVATIONS OF STAR FORMATION INDUCED BY GALAXY-GALAXY AND GALAXY-INTERGALACTIC MEDIUM INTERACTIONS WITH AKARI

  • Suzuki, T.;Kaneda, H.;Onaka, T.
    • 천문학논총
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    • 제27권4호
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    • pp.243-248
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    • 2012
  • Nearby spiral galaxies M101 and M81 are considered to have undergone a galaxy-galaxy interaction. M101 has experienced HI gas infall due to the interaction. With AKARI far-infrared (IR) photometric observations, we found regions with enhanced star forming activity, which are spatially close to regions affected by the interaction. In addition, the relation between the star formation rate (SFR) and the gas content for such regions shows a significant difference from typical spiral arm regions. We discuss possible explanations for star formation processes on a kiloparsec scale and the association with interaction-triggered star formation. We also observed the compact group of galaxies Stephan's Quintet (SQ) with the AKARI Far-infrared Surveyor (FIS). The SQ shows diffuse intergalactic medium (IGM) due to multiple collisions between the member galaxies and the IGM. The intruder galaxy NGC 7318b is currently colliding with the IGM and causes a large-scale shock. The 160 micron image clearly shows the structure along the shock ridge as seen in warm molecular hydrogen line emission and X-ray emission. The far-IR emission from the shocked region comes from the luminous [CII]$158{\mu}m$ line and cold dust (~ 20 K) that coexist with molecular hydrogen gas. Survival of dust grains is indispensable to form molecular hydrogen gas within the collision age (~ 5 Myr). At the stage of the dusty IGM environment, [CII] and $H_2$ lines rather than X-ray emission are powerful cooling channels to release the collision energy.

초고분자량 폴리에틸렌 나노복합체 필름 : 열적-기계적 성질, 모폴로지 및 기체 투과도 (Ultra High Molecular Weight Polyethylene Nanocomposite Films : Thermomechanical Property, Morphology, and Gas Permeability)

  • 정민혜;김정철;장진해
    • 폴리머
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    • 제31권5호
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    • pp.428-435
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    • 2007
  • 종류가 다른 두 가지 유기화 점토를 사용하여 얻은 초고분자량 폴리에틸렌(UHMWPE) 나노복합재료의 열적, 기계적 성질 및 기체 투과도를 서로 비교하였다. UHMWPE 복합체 필름을 얻기 위해 유기화 점토로는 헥사메틸렌 벤즈이미다졸-마이카($C_{16}BIMD-Mica$)와 Cloisite 25A가 사용되었다. 용액 삽입법을 이용하여 UHMWPE에 여러 다른 농도의 유기화 점토를 분산시켜 나노 크기의 복합재료를 합성하였다. 투과 전자 현미경(TEM)을 이용하여 비록 일부는 뭉쳐진 점토의 형태를 나타내었지만 한편으로는 점토가 나노 크기로 고루 분산되었음을 확인하였다. 약간의 유기화 점토 첨가(1-3 wt%) 만으로도 순수한 UHMWPE에 비해서 나노복합재료의 열적, 기계적 성질 및 기체투과도 성질이 높아짐을 알았다. 또한 전체적으로는 첨가된 두가지 유기화 점토 모두 적당한 농도에서 UHMWPE의 물성 증가에 큰 효과가 있었으며, 매트릭스 고분자에 사용된 두 가지 충전제중 Cloisite 25A가 $C_{16}BIMD-Mica$ 보다더 우수한 물성을 보였다.

기능화된 탄소나노튜브를 이용한 초고분자량 폴리에틸렌 복합체 필름: 열적 기계적 성질, 모폴로지, 전기적 성질 및 기체 투과도 (Ultrahigh Molecular Weight Polyethylene Hybrid Films with Functionalized-MWNT: Thermomechanical Properties, Morphology, Gas Permeability, and Optical Transparency)

  • 고정호;김정철;장진해
    • 폴리머
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    • 제33권2호
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    • pp.97-103
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    • 2009
  • 기능화 탄소나노튜브인 4-cumylphenol-MWNT(CP-MWNT)를 이용하여 초고분자량 폴리에틸렌(ultra high molecular weight polyethylene (UHMWPE))/CP-MWNT 복합체 필름을 용액 삽입법을 이용하여 제조하였다. 0에서 2.00 wt%까지의 서로 다른 CP-MWNT의 농도에 따라 만들어진 복합체 필름의 열적, 기계적, 기체 투과도 및 광학 투명성 등의 변화를 시차주사열량계, 열중량분석기, 전계 방사형 주사전자현미경과 인장시험기를 사용하여 측정하였다 복합체 필름은 기능화된 탄소나노튜브를 소량 첨가하여도 열역학적 특성이 향상되는 것을 확인할 수 있으며 0.50에서 1.00 wt%의 농도에서 최대값을 가진다. CP-MWNT의 농도가 1.00 wt%일 때 필름의 산소 기체 차단성은 최대 향상을 나타내었다. 전체적으로는 CP-MWNT가 첨가된 복합체 필름의 열적-기계적 성질 및 기체 투과도 등은 순수한 UHMWPE보다 더 향상되었다.

Effect of Stewing Time on the Small Molecular Metabolites, Free Fatty Acids, and Volatile Flavor Compounds in Chicken Broth

  • Rong Jia;Yucai Yang;Guozhou Liao;Yuan Yang;Dahai Gu;Guiying Wang
    • 한국축산식품학회지
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    • 제44권3호
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    • pp.651-661
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    • 2024
  • Chicken broth has a taste of umami, and the stewing time has an important effect on the quality of chicken broth, but there are fewer studies on the control of the stewing time. Based on this, the study was conducted to analyze the effects of different stewing times on the sensory, small molecular metabolites, free fatty acids, and volatile flavor compounds contents in chicken broths by liquid chromatography-quadrupole/time-of-flight mass spectrometry, gas chromatography-mass spectrometry, headspace solid-phase microextraction, and gas chromatography-mass spectrometry. Eighty-nine small molecular metabolites, 15 free fatty acids, and 86 volatile flavor compounds were detected. Palmitic and stearic acids were the more abundant fatty acids, and aldehydes were the main volatile flavor compounds. The study found that chicken broth had the best sensory evaluation, the highest content of taste components, and the richest content of volatile flavor components when the stewing time was 2.5 h. This study investigated the effect of stewing time on the quality of chicken broth to provide scientific and theoretical guidance for developing and utilizing local chicken.