• 제목/요약/키워드: new chemicals

검색결과 453건 처리시간 0.028초

Environmental Biosensors for Organochlorines, Cyanobacterial Toxins and Endocrine Disrupting Chemicals

  • Sadik, Omowunmi A.;Ngundi, Miriam M.;Yan, Fei
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제5권6호
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    • pp.407-412
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    • 2000
  • Environmental biosensors and related techniques for monitoring organochlorines, endocrine disrupting chemicals and cyanobacterial toxins are described. The practical requirements for an ideal environmental biosensor are analyzed. Specific case studies for environmental applications are reported for triazines, chlorinated phenols, PCBs, microcystins, and endocrine disrupting chemicals. A new promising approach is reported for microcystins and alkylphenols that utilize electrooptical detection.

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Reactive Mesogen Mixtures for Integrated Optical Films

  • Lee, Hee-Kyu;Lee, Seung-Eun;Cumming, S.A.;Verrall, M.;Parri, O.;Harding, R.;Marden, S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.266-269
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    • 2003
  • TFT LCD mode has some well-documented performance limitations, namely limited viewing angle, inversion of the gray scale levels and poor luminance efficiency because of the necessity of using crossed polarisers attached to the display cell. During the last few years many initiatives have been undertaken to solve these problems by incorporation birefringent films of various designs into the LCD module. Controlling the optical performance of LCDs often requires combination of liquid crystal material properties, cell parameters and optical films. Such optical films have traditionally been made with stretched polymer materials such as polycarbonate, but recently coated liquid crystalline materials have been used to give improved optical films which can greatly enhance the performance of LCDs. We have now developed reactive mesogen materials to add ultra-thin optical layers into the display structure, and these allow the potential for many new applications.

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Biaxial integrated optical film for VA mode LCD's made from in-situ photopolymerised reactive mesogens.

  • Kim, Kyeong-Hyeon;Lyu, Jae-Jin;Chung, Dong-Hoon;Verrall, M.;Slaney, K.;Perrett, T.;Parri, O.;Lee, Seung-Eun;Lee, Hee-Kyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.773-775
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    • 2004
  • For high end, large area displays, all current LC modes require some degree of optical compensation to improve the front of screen viewing experience. Currently most optical films are laminated to the outside of the LCD cell, between the glass and polariser. In this paper we wish to show how it is possible to integrate the compensating optical film within a VA mode LCD cell. The paper will describe the process of making the biaxial film through the process of in-situ photopolymerisation of an aligned film of reactive mesogens in the cholesteric phase using polarised UV light. The film can be made on the colour filter array side of the LCD panel. In addition the process of fabricating a VA mode LCD containing this film will be described and the performance of this module will be presented

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Biaxial Integrated Optical Film for VA Mode LCD's Made from In-situ Photopolymerised Reactive Mesogens

  • Kim, Kyeong-Hyeon;Lyu, Jae-Jin;Chung, Dong-Hoon;Verrall, M;Slaney, K;Perrett, T;Parri, O;Lee, Seung-Eun;Lee, Hee-Kyu
    • Journal of Information Display
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    • 제5권2호
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    • pp.23-26
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    • 2004
  • For high end, large area displays, all current LC modes require some degree of optical compensation to improve the front of screen viewing experience. Currently most optical films are laminated to the outside of the LCD cell, between the glass and polariser. In this paper we wish to show how it is possible to integrate the compensating optical film within a VA mode LCD cell. The paper will describe the process of making the biaxial film through the process of in-situ photopolymerisation of an aligned film of reactive mesogens in the cholesteric phase using polarised UV light. The film can be made on the colour filter array side of the LCD panel. In addition the process of fabricating a VA mode LCD containing this film will be described and the performance of this module will be presented.

접촉분해경유로부터 산화황화합물의 분리에 관한 추출용매의 영향 (Effect of Extraction Solvent on the Separation of Sulfur Components in Light Cycle Oil)

  • 박수진;정광은;채호정;김철웅;정순용;구기갑
    • Korean Chemical Engineering Research
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    • 제46권5호
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    • pp.965-970
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    • 2008
  • 접촉분해경유의 산화반응후 포함된 산화황화합물을 분리하기위해 다양한 용매를 사용하여 용매추출에 관한 연구를 수행하였다. 용매로는 극성을 가진 물, N-메틸피놀리논, 에틸아세테이트, 디메틸포름아마이드, 이소프로필알코올, 아세토니트릴, 메탄올등을 사용하였다. 실험결과, 접촉분해경유와 용매와의 층분리는 적절한 양의 물을 첨가한 경우에 이루어졌으며, 물과 N-메틸피놀리논을 혼합한 혼합용매가 접촉분해경유로부터 산화황화합물의 선택적인 분리에 가장 적절하였다. 또한 접촉분해경유로부터 황화합물을 99.5% 이상으로 제거하기 위해선, 4단 정도의 평형추출이 필요하였다.

OECD 대량생산화학물질 위해성평가 및 대책 (Risk Assessment in OECD High Production Volume Chemicals Program and its Countermeasure)

  • 김명진;배희경;최연기;김미경;구현주;송상환;최광수
    • 환경영향평가
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    • 제14권5호
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    • pp.347-353
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    • 2005
  • The risk assessment is the qualitative or quantitative evaluation of the risk posed to human health and the environment by the actual or potential presence or release of hazardous substances, pollutants or contaminants. The environmental impact assessment (EIA) is assessed by the environmental criteria, and risk assessment is assessed by the risk rate. Risk rate based on dose-response values may not be easy to apply on regulatory basis like EIA for uncertainty. Internationally there is an example of OECD program. Risk assessment of High Production Volume (HPV) Chemicals has started since the OECD Program with the 1990 Council Act on the Co-operative Investigation and Risk Reduction of Existing Chemicals. These HPV chemicals include all chemicals produced or imported at levels greater than 1,000 tonnes per year in at least one Member country or in the European Union region. The SIDS called the Screening Information Data Set is regarded as the minimum information needed to assess an HPV chemical to determine whether any further work should be carried out or not. All the data elements of SIDS including assessment for environment and health are prepared as three formats of the full SIDS Dossier, the SIDS Initial Assessment Report (SIAR), and the SIDS Initial Assessment Profile (SIAP) of an HPV chemical. In 1998 the global chemical industry through the International Council of Chemical Associations (ICCA) has joined to work with OECD. The OECD has assessed approximately 1,000 chemicals from 1991 through 2004 with ICCA. Till the February of 2005, 592 chemicals of those chemicals completed SIDS reports. Member countries have been targeted the goal of 1,000 new chemicals from 2005 to 2010 and Korea shared 36 chemicals from the 1,000 new chemicals. Currently Korea has completed SIDS reports of 7 chemicals among sponsored 24 chemicals. In conclusion SIDS project will be linked to national program for outputs application with more reliable production. Both the OECD and industry will carry out their commitment to complete assessments for more and the remaining chemicals assessment. The major outputs will contribute to cope with international chemical management.

식품 중 신종유해물질의 관리 및 분석 (Analysis and management of new hazard chemicals in foods)

  • 최동미;허수정;서정혁;윤태형;김은주;최장덕;박성국;이광호
    • 분석과학
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    • 제22권2호
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    • pp.172-185
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    • 2009
  • 식품 중에서 새롭게 생성되는 유해물질에 대한 정확한 이해를 돕기 위하여 식품의 제조가공과정 중에 불가피하게 생성되는 유해물질의 특성, 생성 메카니즘, 규제 및 분석현황을 정리하였다. 식품 중 신종유해물질은 생성원인인 열처리, 발효, 첨가물질, 미지물질에 따라 크게 4부류로 분류되어 진다. 열처리에 의해 생성되는 식품 중 신종유해물질에는 아크릴아마이드, 퓨란, HCAs, PAHs가 포함된다. 발효공정에 따라서는 에틸카바메이트, 바이오제닉 아민류가 생성된다. 식품첨가물에 의해서는 3-MCPD, 벤젠, 니트로사민류가 생성되며, 미지물질에는 발기부전치료제나 비만치료제 성분을 변형시킨 부정유해물질이 포함된다. 식품 중 신종유해물질을 분석하기 위해서는 액액추출 또는 SPE로 정제하거나 휘발성 성분을 headspace로 포집하여 액체크로마토그래피나 가스크로마토그래피로 분리한 후 자외부흡광기, 형광검출기나 질량분석기로 검출하는 방법이 주로 이용되고 있다.