• 제목/요약/키워드: atmospheres

검색결과 385건 처리시간 0.021초

박막 트랜지스터 채널용 IGZO 박막의 제작

  • 김대현;김상모;최형욱;최영규;김경환
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
    • /
    • pp.137-137
    • /
    • 2009
  • Indium Gallium Zinc Oxide (IGZO) thin films for TFT channel were prepared by using a Facing Target Sputtering (FTS) system. To investigate the effect of oxygen on the optical and the electrical properties of amorphous InGaZnO(a-IGZO), we prepared thin films by FTS system in various oxygen atmospheres at room temperature. As-deposited IZTO thin films were investigated by using a UV/VIS spectrometer, an X-ray diffractometer, a Hall Effect measurement system, and an atomic force microscope. The quantitative analysis of the films was carried out by using the energy dispersive X-ray (EDX) technique for the as-deposited film.

  • PDF

Dehydrogenation of Ethylbenzene with Carbon Dioxide as Soft Oxidant over Supported Vanadium-Antimony Oxide Catalyst

  • Hong, Do-Young;Vislovskiy, Vladislav P.;Park, Sang-Eon;Park, Min-Seok;Yoo, Jin-S.;Chang, Jong-San
    • Bulletin of the Korean Chemical Society
    • /
    • 제26권11호
    • /
    • pp.1743-1748
    • /
    • 2005
  • This work presents that carbon dioxide, which is a main contributor to the global warming effect, could be utilized as a selective oxidant in the oxidative dehydrogenation of ethylbenzene. The dehydrogenation of ethylbenzene over alumina-supported vanadium-antimony oxide catalyst has been studied under different atmospheres such as inert nitrogen, steam, oxygen or carbon dioxide as diluent or oxidant. Among them, the addition of carbon dioxide gave the highest styrene yield (up to 82%) and styrene selectivity (up to 97%) along with stable activity. Carbon dioxide could play a beneficial role of a selective oxidant in the improvement of the catalytic behavior through the oxidative pathway.

Corrosion Behaviour of Some Alloys in Tropical Urban and Marine Atmospheres

  • Dang, Vu Ngoan;Bui, Ba Xuan;Nguyen, Nhi Tru
    • Corrosion Science and Technology
    • /
    • 제7권2호
    • /
    • pp.125-129
    • /
    • 2008
  • Results of corrosion testing for different grades of titanium, copper, zinc, alluminium alloys and steels after two years of outdoor exposure under humid tropical urban and marine conditions have been presented and discussed. Mass loss and corrosion product characteristics for the exposed specimens at Hanoi testing site with high humidity and Nhatrang marine stations (at 100 and 1,000 meters distances from sea) with different airborne salinities (35.9 and $90.0mg/m^2.d$ respectively) have been selected for investigation. From time dependence of the specimen mass loss and corrosion product characteristics, the strong influence of environmental parameters upon durability for the investigated metals and alloys has been demonstrated. Only titanium alloys show high resistance to the marine conditions. All the other specimens (copper, zinc, alluminium alloys and steels) have been underwent strong deterioration under influence of aerosol salinity. Results of corrosion products analysis have been also presented for characterization of environmental impact on the metal degradation processes.

일본 중국 유학생의 한식당의 서비스 품질 요인에 관한 중요도 및 만족도 (Importance and Satisfaction with the Service of Korean Restaurants for Japanese and Chinese Students in Korea)

  • 서경화;신민자
    • 동아시아식생활학회지
    • /
    • 제16권6호
    • /
    • pp.753-762
    • /
    • 2006
  • The purpose of this research is to analyze the importance and satisfaction level with the service of Korean restaurants for Japanese and Chinese students in Korea. Self adminstered guestionnaires were collected from 204 Japanese and Chinese students in Korea. The data was statistically analysed using t-tests, one-way ANOVA, reliability test, factor analysis and regression test. The average values of importance-factor and satisfaction-factor were significantly different. Based on analyses of the 20 service level factors, satisfaction level was significantly lower than importance level. Satisfaction-factors such as quality of food, hygiene of restaurant and employees, service level, and atmospheres, significantly influenced the overall satisfaction level of Korean food and restaurants.

  • PDF

Alpha Track Detector를 이용한 실내외 라돈 농도조사에 관한 연구 (A Survey of Indoor and Outdoor Radon Concentrations by Alpha Track Detector in Korea)

  • 김윤신;이철민;김현탁
    • 한국환경보건학회지
    • /
    • 제28권5호
    • /
    • pp.71-76
    • /
    • 2002
  • A survey of radon concentrations in both indoor and outdoor atmospheres was carried out using EIRM and Cup Monitor for the period of February 1996 to March 1997. EIRM were used to measure the indoor and outdoor radon concentration at five major cities university. Cup Monitor were also used to measure the indoor radon concentrations at shopping store, office building, apartment, hospital and house in Seoul. The mean indoor and outdoor radon concentrations at the five major cities(Seoul, Daegu, Daejon, Cwangiu and Busan) were 24.1 Bq/m$^3$and 8.62 Bq/m$^3$, respectively. The ratio of indoor to outdoor radon concentrations ranged front 1.7 to 3.9. Inspection of its seasonal distribute pattern indicates the enhancement during winter relative to summer, consistently for both indoor and outdoor air. The results of the survey showed that the concentrations in basements were clearly higher than those in usual living/working places.

고분자 내부에 용해된 기체가 수 트리 성장에 미치는 영향 (The Influence of Gases in Solution in the Polymer on the Growth of Water Trees)

  • 김진기;김정태;구자윤
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1990년도 추계학술대회 논문집 학회본부
    • /
    • pp.125-128
    • /
    • 1990
  • The growth of water trees was measured using CNRS Laboratory Models in laboratory polyethylene specimens. The effect of deaerating the specimens, and annealing them under different gaseous atmospheres was investigated. These factors were found to be secondary in the growth of water trees. The gas in contact with the material during the growth of water trees is considered not to influence the intiation stage but the propagation stage.

  • PDF

A TWO CAVITY MODEL FOR UMBRAL OSCILLATIONS

  • Lee, Jeong-Woo;Yun, Hong-Sik
    • 천문학회지
    • /
    • 제20권1호
    • /
    • pp.27-47
    • /
    • 1987
  • In the present study a two-mode, separately concurring resonant cavity model is proposed for theoretical interpretation of the 3 minute umbral oscillation. The proposed model has been investigated by calculating the transmission coefficients of the waves propagating through the umbral photosphere (photospheric weak-field cavity) and chromosphere (chromospheric strong-field cavity) into the corona, for 3 different umbral model atmospheres by Staude (1982), Beebe et al. (1982) and Avrett (1981). In computing the transmission coefficients we made use of multi-layer approximation by representing the umbra] atmosphere by a number of separate layers with (1) temperature varying linearly with depth and (2) temperature constant within each layer. The medium is assumed to be compressible, non-viscous, perfectly conducting under gravity. The computed resonant periods, transmission spectra, phase spectra, and kinetic energy density of the waves associated with the oscillations are presented in comparison with the observations and their model dependent characteristics are discussed.

  • PDF

건조 대추의 변형기체포장 (Modified Atmosphere Packaging of Dry Jujube)

  • 하정욱;이동선
    • 한국식품저장유통학회지
    • /
    • 제4권3호
    • /
    • pp.265-270
    • /
    • 1997
  • Effect of modified atmosphere packaging conditions on quality changes of dry jujube was investigated. Dry jujubes with moisture content of 26.7% were packaged in PET/Al/PE film pouches with modified atmospheres. The tested packages include those with normal air, vacuum, CO2 flushing, N2 flushing and O2 scavenger. Packages were stored at 25$^{\circ}C$ for 6 months, during which ascorbic acid concentration, browning level, titratable acidity and surface color were measured. Generally modified atmosphere packages could improve quality retention of dry jujubes except that vacuum package resulted in large surface color change. CO2-flushed package showed the best quality retention of high ascorbic acid content and low browning during 112 days, but caused high amounts of ascorbic acid destruction and browning in longer storage. In all the modified atmosphere packages titratable acidity reached a maximum followed by decline and subsequent rise, while it increased linearly with time in normal air package. Considering ascorbic acid retention browning level and surface color changes during 112 days, the packages of CO2 flushing and N2 flushing were better than others.

  • PDF

표고버섯의 평형함수율에 관한 연구 (Equilibrium Moisture Content of Shiitake Mushroom(Lentinus edodes))

  • 최병민;한은정;최주호;홍지형;서재신
    • 한국식품저장유통학회지
    • /
    • 제6권1호
    • /
    • pp.37-42
    • /
    • 1999
  • The equilibrium moisture content(EMC) of Shiitake mushroom is and important factor because it has a close relationship to storage and drying problems. The determination of the EMC for Shiitake mushroom was made in atmospheres of various constant humidities at four different constant temperatures and the fitting of the five selected EMC models were performed with the experimental EMC data. The desorption equilibrium moisture contents for Shiitake mushroom were increased as the temperature was decreased and the relative humidity was increased. The significant difference of the equilibrium moisture content was appeared between the cap and the stipe of Shiitake mushroom. The Henderson-Thompson model was fitter than the others with the experimental data.

  • PDF

한국·미국·대만의 유아대상 TV광고 비교 (A Comparison of Korean, American, Taiwanese Television Commercials for Young Children)

  • 이미혜;홍혜경
    • 아동학회지
    • /
    • 제22권3호
    • /
    • pp.137-150
    • /
    • 2001
  • In this cross-national analysis of commercials for young children, 58 commercials were from KBS 2 in S. Korea, 51 from Nickelodeon, USA, and 69 from CTV, Taiwan, totaling 178 commercials. Differences between countries were that foods and beverages were mainly advertised in S. Korean and Taiwanese while a full range of items were evenly displayed in American commercials, and American commercials used more ordinary people in casting. Fantastic and realistic atmospheres were typical of S. Korean, realistic and explanatory of American, and explanatory of Taiwanese commercials. The commercials rarely showed an aesthetic sense or creative thinking, and the use of abusive language and aggression was ubiquitous, while some deviant behavior was also portrayed. The commercials often failed to provide useful information, and they stimulated customers to have unrealistic expectations.

  • PDF