• Title/Summary/Keyword: toxic gas

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Detection of H2S Gas with CuO Nanowire Sensor (산화구리 나노선 센서의 황화수소 감지특성)

  • Lee, Dongsuk;Kim, Dojin;Kim, Hyojin
    • Korean Journal of Materials Research
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    • v.25 no.5
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    • pp.238-246
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    • 2015
  • $H_2S$ is a flammable toxic gas that can be produced in plants, mines, and industries and is especially fatal to human body. In this study, CuO nanowire structure with high porosity was fabricated by deposition of copper on highly porous singlewall carbon nanotube (SWCNT) template followed by oxidation. The SWCNT template was formed on alumina substrates by the arc-discharge method. The oxidation temperatures for Cu nanowires were varied from 400 to $800^{\circ}C$. The morphology and sensing properties of the CuO nanowire sensor were characterized by FESEM, Raman spectroscopy, XPS, XRD, and currentvoltage examination. The $H_2S$ gas sensing properties were carried out at different operating temperatures using dry air as the carrier gas. The CuO nanowire structure oxidized at $800^{\circ}C$ showed the highest response at the lowest operating temperature of $150^{\circ}C$. The optimum operating temperature was shifted to higher temperature to $300^{\circ}C$ as the oxidation temperature was lowered. The results were discussed based on the mechanisms of the reaction with ionosorbed oxygen and the CuS formation reaction on the surface.

Reactivity Considerations with Miscibility of Process Gases in Semiconductor industry (반도체 산업 공정가스의 혼화성에 따른 반응성 고찰)

  • Lee, Keun Won
    • Journal of the Korean Institute of Gas
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    • v.20 no.4
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    • pp.15-24
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    • 2016
  • In the semiconductor industry, the risk of chemical accidents due to miscibility between the many types of chemicals and leakage of toxic chemicals has increased. In order to evaluate the reactivity with miscibility of chemicals, experimental method is the most reliable, but there is a time and cost limitations to be evaluated through experiment all the chemicals. In the study, the reactivity of process gases in the semiconductor industry was considered by the CRW (Chemical Reactivity Worksheets) 3.0 program developed by US NOAA (National Oceanic and Atmospheric Administration) and EPA. The reactivity informations with the miscibility of process gases for semiconductor industry provided, and also a KOSHA guide for the storage/separation of gas cylinders in dispensing cabinets in the semiconductor industry was proposed.

Development and Selection of Accident Scenarios for Risk Assessment in HF Charging Process (HF 충진 공정의 위험성 평가를 위한 가상사고 시나리오 발굴 및 선정)

  • Jang, Chang-Bong
    • Journal of the Korean Institute of Gas
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    • v.17 no.4
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    • pp.26-32
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    • 2013
  • The best way to prevent major occupational accidents is prohibiting use of hazardous substances such as flammable gas, toxic gas whereas using alternative substances that ensured safety. but if there are no economic efficiency and substituting technologies of alternative substances, the best way is preparing to prevent accidents thoroughly. Therefore, this study has developed and selected release scenarios to use and apply for consequence analysis and emergency action plan for HF charging process of chemical plants that have HF release accidents and high probability of release accidents.

The Electron temperature and Density properties of Mixing gas in ICP Lighting system(Ne:Xe, Ne:Ar) (ICP 광원 시스템의 Ne:Xe Ne:Ar 혼합가스의 전자온도 및 전자밀도의 특성 연구)

  • Choi, Gi-Seung;Lee, Jonh-Chan;Choi, Yong-Sung;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2424-2426
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    • 2005
  • In whole world consciousness of environment maintenance have increased very quickly for he end of the 20th century. To use and disuse toxic substances have been controled at the field of industry. Also the field of lighting source belong to environmental control. And in the future the control will be strong. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem root. In the mercury free lighting source system the Xe gas lamp is one type. And the Ne:Xe and Ne:Ar mixing gas lamp improvements firing voltage of Xe gas lamp. Purpose and subject of this study are understand, efficiency, ideal of Ne:Xe and Ne:Ar plasma which mercury free lamp. Before ICP was designed, basic parameters of plasma, which are electron temperature and electron density, were measured and calculated by langmuir probe data. Property of electron temperature and electron density were confirmed by changing ratio of Ne:Xe and Ne:Ar.

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Conceptual Design and Operation Results for SF6 Decomposition and Pollution Control System (SF6 분해 및 무해화 시스템의 개념 설계 및 운영 결과)

  • Joongwon, Lee;Miyeong, Kim;Jiho, Ahn;Younghwan, Byun
    • KEPCO Journal on Electric Power and Energy
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    • v.8 no.2
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    • pp.111-118
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    • 2022
  • SF6 is used as an insulating gas because of its excellent electrical insulation properties, non-toxicity, and non-inflammability. On the other hand, the global warming potential of SF6 is 23,900 times higher than that of CO2. The Korea electric power cooperation (KEPCO) is responsible for 80% of the domestic SF6 usage, and approximately 6,000 tons are currently charged in electrical and power facilities. KEPCO will gradually replace the insulating gas with SF6-free gas from 2023. SF6 decomposition facilities are required because more than 60 tons of SF6 will need to be disposed of annually from existing equipment. This study developed a novel decomposition and pollution control system that can process 60 tons of SF6 per year. This facility can decompose more than 97.7% of SF6, with the emissions of hazardous and toxic materials below the legal limit.

Analysis of Carbon Dioxide Exchange and Toxic Gas Behavior in the Urban-Type Plant Factory System (도시형 식물공장 시스템의 탄산가스 변화 및 유해가스 거동분석)

  • 박종석;손정익;박한영
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1998.10a
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    • pp.69-72
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    • 1998
  • 도시환경은 다양한 형태로 발생되는 공해로 인해 악화되고 있으며 이러한 환경은 인간의 건강을 위협하며, 도시뿐 아니라 주변지역으로의 환경파괴를 가속시키고 있다. 도시 내에서 발생하는 탄산가스, 폐열 등의 인간에게 유해한 물질을 농업으로 전환시켜 농업생산에 이용하는 것은 필요하다고 할 수 있다. 도시내의 잉여 이산화탄소를 이용하여 식물을 생산하고 식물재배공간으로부터 나오는 신선한 공기를 인간이 이용하는 도시형 식물공장의 개념은 환경과 생산의 두 가지 측면을 가지고 있다. (중략)

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Study on the preparation Of Octa(2-ethyhexyloxy) copper-phthalocyanine LB film (Octa(2-ethyhexyloxy) copper-phthalocyanine의 LB막 제작에 관한 연구)

  • 임준석;김영관;김정수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.228-231
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    • 1995
  • Phthalocyanine have a good sensitivity to the toxic gases like NO$_2$. Also its properties of good chemical and thermal suability give a potential to superiors gas sensing system. Depositioni of Octa(2-ethyhexyloxy) Copper Phthalocyanine is confirmed by transfers ratio, UB/visible spectra and current-voltage (I-V) characteristics.

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A Study on Light-weight Inorganic Insulation (경량 무기 단열재에 관한 연구)

  • Shin, Hyeon-Uk;Song, Hun;Chu, Yong-Sik;Lee, Jong-Kyu
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.05a
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    • pp.217-218
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    • 2012
  • To prevent energy waste in buildings used heat insulator. Heat insulator materials can be classified inorganic and organic. The organic material is be toxic gas emission, when a fire occurs. And it has lower water resistance. The inorganic material is heavy and worse thermal performance than organic materials. This study focused on thermal conductivity and density of inorganic foam material for using industrial by-products materials.

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Development of a Lagrangian Stochastic Dispersion Model for Toxic Gas Release (독성 기체상 물질의 확산 및 대응 분석을 위한 라그랑지안 입자모델의 개발)

  • 이강웅;장유운;이미혜;조성억;조승현
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.149-151
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    • 1999
  • 우리 나라의 경우에 산업화가 가속화되면서 유해 독성 기체상 물질의 누출사고 위험성이 점점 높아져 가고 있는 실정이다. 우리 나라는 특히 산업인력의 조달과 지방경제 발달을 목적으로 중소도시 근방에 대규모 공단이 건설되어 있는 경우가 많다. 이러한 공단에는 위험물을 취급하는 공장과 위험물이 수송 및 이동되는 사례가 매우 많을 것으로 추정되며 이러한 경로를 통하여 유독가스 누출사고가 발생 할 경우 바로 인근 주민 및 작업 인원들의 생명을 위협할 수 있다.(중략)

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A Study on the Characteristics of Electro Polishing and Utility Materials for Transit High Purity Gas (청정도 가스 이송용 재료의 특성과 전해연마에 관한 연구)

  • Lee, Jong-Hyung;Park, Shin-Kyu;Yang, Seong-Hyeon
    • Journal of the Korean Society of Industry Convergence
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    • v.7 no.3
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    • pp.259-263
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    • 2004
  • In the manufacture progress of LCD or semiconductor, there are used many kinds of gas like erosion gas, dilution gas, toxic gas as a progress which used these gas there are required high puritize to increase accumulation rate of semiconductor or LCD materials work progress of semiconductor or LCD it demand many things like the material which could minimize metallic dust that could be occured by reaction between gas and transfer pipe laying material, illumination of the surface, emition of the gas, metal liquation, welding etc also demand quality geting stricted. Material-Low-sulfur-contend (0.007-0010), vacuum-arc-remelt(VAR), seamless, high-purity tubing material is recommend for enhance welding lower surface defect density All wetted stainless steel surface must be 316LSS elecrto polishinged with ${\leq}0.254{\mu}m$($10.0{\mu}in$) Ra average surface finish, $Cr/Fe{\geq}1.1$ and $Cr_2O_3$ thickness ${\geq}25{\AA}$ From the AES analytical the oxide layer thickness (23.5~36 angstroms silicon dioxide equivalent) and chromum to iron ratios is similar to those generally found on electropolished stainless steel., molybdenum and silicon contaminants ; elements characteristic of stainless steel (iron, nickel and chromium); and oxygen were found on the surface Phosphorus and nitrogen are common contaminants from the electropolish and passivation steps.

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