• 제목/요약/키워드: Environmentally benign

검색결과 93건 처리시간 0.024초

Radical Polymers and Organic Radical Battery

  • Nishide, Hiroyuki
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.62-62
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    • 2006
  • Based on the redox couples of a nitroxide radical, organic radical polymers were utilized as the electrode-active or charge-storage component for a secondary battery. We call a battery composed of the radical polymer electrode as "organic radical battery". Organic radical battery has several advantages: high capacity, high power-rate performance, long cycle ability, and environmentally-benign features. Synthesis and electrochemical studies of nitroxide polymers are described. Battery fabrication and cell performance are also reported.

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Synthesis of 2-Arylbenzothiazoles Catalyzed by Biomimetic Catalyst, β-Cyclodextrin

  • Londhe, Balaji S.;Pratap, Umesh R.;Mali, Jyotirling R.;Mane, Ramrao A.
    • Bulletin of the Korean Chemical Society
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    • 제31권8호
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    • pp.2329-2332
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    • 2010
  • Cyclocondensation of 2-aminothiophenol and aryl/heteryl aldehydes has been carried using biomimetic catalyst, $\beta$-Cyclodextrin in water and obtained 2-aryl/heteryl benzothiazoles with better to excellent yields. This biomimetic catalyzed route is simple, economic, and environmentally benign.

환경친화적인 유-무기 복합코팅 강판의 개발과 품질특성 (Development and Quality Evaluation of Environmentally-benign Organic-Inorganic Composite Coated Steel Sheet)

  • 조두환;이재륭
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2008년도 추계학술대회 초록집
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    • pp.134-134
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    • 2008
  • 아연도금강판은 유-무기 코팅 처리를 통해 도금층 표면의 방청성 향상과 추가적인 고기능성을 부여한다. 최근 POSCO 에서는 가전, 건재 및 자동차용으로 사용하기 위해 다양한 Cr-free 코팅강판을 개발하였다. 본 발표에서는 기존의 크로메이트 처리 강판을 대체하기 위해 유-무기 복합코팅 강판 개발과 품질특성을 소개하고자 한다.

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폴리머 마이크로렌즈 제작 (Polymer Microlens Fabrication)

  • 류근걸;김영근;전광석
    • 청정기술
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    • 제11권4호
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    • pp.205-211
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    • 2005
  • 마이크로렌즈 어레이의 제작은 매우 다양한 재료와 방법이 제안되어 지고 있으나, 폴리머를 이용한 사출법은 광학적 특성, 내충격성, 가공성, 경량화 및 환경친화성 등의 장점으로 주목 받고 있다. 사출법 템플레이트를 제작하기 위한 PR(Photo-Resist) reflow법은 형상제어가 용이하고 대량생산과 정밀가공의 측면에서 효율적이어서, 집적화가 용이하고 공정을 줄일 수 있는 장점을 갖게 되어 매우 환경친화적이다. 그러나 마이크로렌즈 어레이의 사출성형은 사용되는 폴리머재료의 성질에 따라 성형에 어려움이 있는 것으로 알려져 있다. 본 연구에서는 이와 같은 성형의 어려움을 극복하기 위한 방법으로 급가열/급냉각 사출을 통하여 마이크로렌즈 어레이를 제작하고 특성을 이해하였다. 템플레이트의 급격한 온도상승과 고온에서의 모양이 냉각으로 인한 변형이 없도록 급속히 냉각시켜 줌으로서 마이크로렌즈 어레이의 사출성형을 구현 하였다. PC(Poly-Cabon ate)와 PMMA(Poly-Methyl-Meth-Acrylate)를 비교하여, PMMA가 낮은 용융점에 의해 성형성이 우수함을 확인하였다. 사출시 압력과 속도를 변수로 마이크로렌즈 어레이의 제작을 위한 사출조건을 도출하였다.

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초전도변압기 시장진입가격 예측을 통한 경제성 분석 (Economic Evaluation of HTS Transformer by Predicting Market Penetration Price)

  • 김종율;이승렬;윤재영
    • 대한전기학회논문지:전력기술부문A
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    • 제53권9호
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    • pp.507-512
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    • 2004
  • HTS (High Temperature Superconducting) Transformer has the several useful characteristics in the viewpoints of technical and economical. Especially, an HTS transformer replaces the copper wire coils in a conventional transformer with lower loss HTS wire. In addition, inexpensive, environmentally benign liquid nitrogen replaces the conventional oil as the electrical insulation (dielectric) and provides the necessary cooling for the HTS transformer Therefore, the Life-cycle cost of an HTS transformer is much more attractive than conventional because it is more energy efficient, lighter in weight, smaller in size, and environmentally compliant. HTS transformer can be the best way to replace with conventional transformer in the future. In these days, companies world-wide have conducted researches on HTS transformer. A development project for a 154kV HTS transformer is proceeding at a research center and university in Korea. In this paper, we investigate the expected price of HTS transformer to have a merit in viewpoint of economic aspect. First, life-cycle cost of conventional transformer is calculated and based on this, the expected price of HTS transformer is evaluated. which HTS transformer is competitive against conventional transformer.

수중에서 금속 촉매의 니트릴 수화 반응에 의한 환경친화적 아미드 합성 (Environmentally Friendly Synthesis of Amide by Metal-catalyzed Nitrile Hydration in Aqueous Medium)

  • 무하마드 아십 후세인;김정원
    • 공업화학
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    • 제26권2호
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    • pp.128-131
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    • 2015
  • 친환경적 조건에서의 니트릴의 수화 반응은 아미드를 생산하기 위한 가장 경제적이고 매력적인 방법이다. 고체 금속 산화물과 지지체를 이용한 전이 금속 촉매 시스템은 이러한 니트릴 수화 반응을 보다 향상시키기 위한 의미 있는 연구로써 수행되어져 왔다. 이들 촉매들의 중요한 특징은 방향족, 지방족, 이종 원자형, 지방족 고리형 등의 니트릴들을 포함하는 넓은 범위의 다양한 기질들에 적용된다는 것이다. 또한 이들은 높은 촉매적 활성을 유지하면서 여러 번의 재사용성이 가능하고 반응 후 그 혼합물로부터 분리가 용이하다는 장점들을 갖는다. 이 리뷰를 통하여 니트릴 수화반응을 통한 아미드 합성에 적용되는 금속 산화물과 지지체를 가진 금속 촉매들에 대해 알아본다.

산화티타늄을 이용한 VOCs의 광촉매 반응 (Photocatalytic Reaction of VOCs Using Titanium Oxide)

  • 정수경
    • 한국환경과학회지
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    • 제17권2호
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    • pp.171-176
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    • 2008
  • The VOCs have a direct influence on indoor air pollution, and stimulate respiratory organs and eyes in human body. Also, most of VOCs are a carcinogenic substances and causes to SBS (sickness building syndrome). Therefore, this study was progressed in photocatalysis of VOCs using UV/$TiO_2$ which was a benign process environmentally. The experiments were performed to know photodegradation characteristics as crystalline structure of $TiO_2$ which had anatase, rutile and P-25 (anatase : rutile = 70 : 30). The main purpose of this study was to identify photocatalytic characteristics as inlet concentration of reactants, $H_2O$, and residence time.

SF6계 혼합가스의 뇌임펄스 절연파괴특성 (Lightning Impulse Breakdown Characteristics of SF6-based Mixture Gases)

  • 서호준;이동희
    • 한국전기전자재료학회논문지
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    • 제18권7호
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    • pp.675-681
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    • 2005
  • $SF_6$ is widely used as gas insulation medium because of having excellent dielectric and arc-quenching properties. However the use of it is getting to be suppressed from the viewpoint of mitigating global warming. For the development of environmentally-benign electric power equipment and system, novel gases or mixture gases are strongly required as the substitute of $SF_6$ gas. In this study the authors constructed an experimental system to investigate insulation properties of the mixed gases composed of negative $gas(SF_6)$ and electron deceleration gases$(N_2\;and\;CO_2)$. Breakdown and prebreakdown characteristics of $SF_6/N_2/CO_2$ mixture gases were investigated using the above mentioned system for different rates and gas pressures.

ZrOCl2.8H2O as an Efficient Catalyst for the Three-Component Synthesis of Triazoloindazoles and Indazolophthalazines

  • Tavakoli, Hamid Reza;Moosavi, Sayed Mojtaba;Bazgir, Ayoob
    • 대한화학회지
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    • 제57권4호
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    • pp.472-475
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    • 2013
  • An efficient and environmentally benign protocol for the three-component synthesis of triazoloindazoles and indazolophthalazines via condensation of dimedone, aldehydes and urazole or phthalhydrazide catalyzed by $ZrOCl_2.8H_2O$ as an inexpensive and eco-friendly catalyst with high catalytic activity under solvent-free conditions is reported. This protocol provides a new and improved method for obtaining triazoloindazoles and indazolophthalazines in terms of good yields, simple experimental procedure and short reaction time.

초음파에너지가 도입된 유화중합공정에서 Polystyrene Latex의 분산도 및 입자분포 특성 (Polydispersity and Particle Size Distribution of Polystyrene Latex Prepared by Ultrasound Induced Emulsion Polymerization)

  • 김원일;홍인권
    • Elastomers and Composites
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    • 제33권2호
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    • pp.110-116
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    • 1998
  • A new technology was introduced to the emulsion polymerization. It is the ultrasonic activation method which replaced a chemical initiator and the environmentally benign process. In this study, free radicals were produced by a pulse type ultrasound energy irradiation, then polystyrene latex was polymerized without chemical initiator. With ultrasonic energy density, the degree of polymerization, average molecular weight, and particle size were increased, but the polydispersity index for the molecular weight and the particle size were decreased. The optimum condition of emulsifier concentration and temperature was found to be 1.0 wt.% SDS and $40^{\circ}C$, respectively. As a result, the emulsion polymerization process without chemical initiator was proved to be comparable to common latex properties such as average molecular weight, molecular weight distribution, particle size, etc.

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