• Title/Summary/Keyword: gases

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Adhesion of Cu on Polycarbonate Modified by O2/ Ar Plasma Treatment (O2/ Ar 플라즈마 처리에 의해 개질된 폴리카보네이트 기판에서 Cu의 밀착성)

  • Park, Jun-Kyu;Kim, Dong-Won;Kim, Sang-Ho;Lee, Youn-Seoung
    • Korean Journal of Materials Research
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    • v.12 no.9
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    • pp.740-746
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    • 2002
  • In this study, the polycarbonate surface was treated by $O_2$/ Ar gases plasma for the enhancement of adhesion with Cu electrode. From the point of view of hydrophilicity and the functionality, the micro-roughness, new functional groups and oxygen content of the polycarbonate surface were increased by the $O_2$/ Ar gases plasma treatment. The Cu films deposited on the as-received polycarbonate were easily detached while, after the$ O_2$/ Ar gases plasma treatment the adhesive Cu films on polycarbonate could be obtained. These results can be explained that the polycarbonate had a hydrophilic surface with uniform micro-roughness and new functional groups by $O_2$/ Ar gases plasma treatment. Therefore,$O_2$/ Ar gases plasma treatment is a promising method for improvement of adhesion between polycarbonate and Cu electrode.

Application Methodology of Greenhouse Gases Emission Table for Various Types of Roads and Vehicles (도로기하구조 조건에 따른 차량별 온실가스 배출량 산정사례 적용연구 - 맑은 날씨를 기준으로 -)

  • Lee, Jonghak;Choi, Jaisung;Noh, Kwansub;Hu, Hyejung
    • International Journal of Highway Engineering
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    • v.18 no.1
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    • pp.23-31
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    • 2016
  • PURPOSES : This study aimed to offer a greenhouse gases table to assist a road designer in calculating the greenhouse gases for a road environment when making a decision about an alternative road. METHODS : This study developed an operation mode table of greenhouse gases using the MOVES program. Similar factors for Korean vehicles and fuels are reflected in the MOVES program, which was made in the USA. Finally, a paired t-test was conducted to calculate the site data and MOVES data. Through these studies, a methodology was suggested for calculating carbon emissions based on various types of roads alignments. RESULTS : The site results for a passenger truck on the road were statistically significant when the vehicle speed was above 65 km/h. However, a future study will consider factors for various road alignments and vehicles. CONCLUSIONS : This study will contribute to the theoretical basis for reducing carbon emissions from roads by helping road designers make decisions about road alternatives in terms of the road environment.

Identification of Gas Mixture with the MEMS Sensor Arrays by a Pattern Recognition

  • Bum-Joon Kim;Jung-Sik Kim
    • Korean Journal of Materials Research
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    • v.34 no.5
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    • pp.235-241
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    • 2024
  • Gas identification techniques using pattern recognition methods were developed from four micro-electronic gas sensors for noxious gas mixture analysis. The target gases for the air quality monitoring inside vehicles were two exhaust gases, carbon monoxide (CO) and nitrogen oxides (NOx), and two odor gases, ammonia (NH3) and formaldehyde (HCHO). Four MEMS gas sensors with sensing materials of Pd-SnO2 for CO, In2O3 for NOX, Ru-WO3 for NH3, and hybridized SnO2-ZnO material for HCHO were fabricated. In six binary mixed gas systems with oxidizing and reducing gases, the gas sensing behaviors and the sensor responses of these methods were examined for the discrimination of gas species. The gas sensitivity data was extracted and their patterns were determined using principal component analysis (PCA) techniques. The PCA plot results showed good separation among the mixed gas systems, suggesting that the gas mixture tests for noxious gases and their mixtures could be well classified and discriminated changes.

Numerical Studies of Cloud Acidification Processes Using a One Dimensional Cumulus Cloud Model (일차원 적운모델을 이용한 산성강우 형성에 관한 수치적 연구)

  • 곽노혁;안상욱;홍민선
    • Journal of Korean Society for Atmospheric Environment
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    • v.7 no.3
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    • pp.145-149
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    • 1991
  • A one dimensiional cumulus cloud model has been developed for the investigation of temporal and altitudinal variation of trace gases and the wet deposition rates of sulfate for different simulation conditions. The results show that the dynamic field, liquid mixing ratios and the solubility of trace gases affect the distribution of trace gases and the droplet pH. Temporal variation of the predicted surface precipitation and sulfate deposition rates agree well with the field data.

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The Study on the Marine Deaerator (선박용 탈기기에 관한 연구)

  • 홍성희;김창수;김두현
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2002.05a
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    • pp.29-34
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    • 2002
  • As the makeup water entering the boiler feed water cycle usually contains corrosive gases, particularly oxygen and carbon dioxide, so the corrosive gases should be eliminated by a deaerator. While the other domestic companies have made a deaerator for land industrial field, our company has developed and is able to produce a spray & scrubber type deaerator for marine to maintain below the level of 7ppb of dissolved oxygen in the condensate. In this paper, we describe the principle, design technique and experimntal results of the spray & scrubber type deaerator.

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A study on the reaction mechanism on the harmful gases related to the human physiology caused by fire and panic phenomenon. (화재발생시의 유해가스의 반응 메카니즘과 패닉현상)

  • Yoon, Moung-Hoon;Kwon, Young-Jin
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.04a
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    • pp.337-340
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    • 2008
  • Smoke composed of harmful gases such as carbon monocide and carbon dioxide is reconized as the major killer in fire situation. Especailly it is said that smoke movement is related to the panic phenomenon which threatens the life seriously. The purpose of this study is to investgate and analyse the reaction mechanism of harmful gas caused by fire effects on the human psychology and panic phenomenon.

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Effect of Adding Hydrocarbon Gases for Reduction of NOx and SOx Using PPCP (탄화수소 가스 첨가가 PPCP 장치에 의한 NOx 및 SOx 저감에 미치는 영향)

  • 김홍석;강형수;정태용
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.5
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    • pp.73-80
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    • 1999
  • To decrease NOx and SOx using PPCP(Pulse-induced Plasma Chemical Process). This study is tried to obtain the relation and the basic data under the various conditions such the initial concentrations of NOx and SOx. The additional amount of hydrocarbon gases. The concentration of oxygen and input power etc. Especially, this study is focused on the effects of the additional hydrocarbon gases on the decrease of NOx and SOx.

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COMBUSTION CHARACTERISTICS OF WASTE-PYROLYSIS GASES IN AN INTERNAL COMBUSTION ENGINE

  • Shudo, T.;Nagano, T.;Kobayashi, M.
    • International Journal of Automotive Technology
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    • v.4 no.1
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    • pp.1-8
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    • 2003
  • Wastes such as shredder dust of disposed vehicles can be decomposed into low calorific flammable gases by Pyrolysis gasification. A stationary electric Power generation using an internal combustion engine fuelled with the waste-pyrolysis gas is an effective way to ease both waste management and energy saving issues. The waste-pyrolysis gas mainly consists of H$_2$, CO, $CO_2$ and $N_2$. The composition and heating value of the gas generated depend on the conversion process and the property of the initial waste. This research analyzed the characteristics of the combustion and the exhaust emissions in a premixed charge spark ignition engine fuelled with several kinds of model gases, which were selected to simulate the pyrolysis-gases of automobile shredder dusts. The influences of the heating value and composition of the fuel were analyzed parametrically. Furthermore, optical analyses of the combustion flame were made to study the influence of the fuel's inert gas on the flame propagation.

Microalgal Removal of $CO_2$from Flue Gases: Changes in Medium pH and Flue Gas Composition Do Not Appear to Affect the Photochemical Yield of Microalgal Cultures

  • Olaizola, Miguel
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.6
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    • pp.360-367
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    • 2003
  • Our research objectives are to determine under what conditions microalgal-based $CO_2$capture from flue gases is economically attractive. Specifically, our objective here was to select microalgae that are temperature, pH and flue gas tolerant. Microalgae were grown under five different temperatures, three different pH and five different flue gas mixtures besides 100% $CO_2$(gas concentrations that the cells were exposed to ranged 5.7-100% $CO_2$, 0-3504ppm SO$_2$, 0-328ppm NO, and 0-126ppm NO$_2$). Our results indicate that the microalgal strains tested exhibit a substantial ability to withstand a wide range of temperature (54 strains tested), pH (20 strains tested) and flue gas composition (24 strains tested) likely to be encountered in cultures used for carbon sequestration from smoke stack gases. Our results indicate that microalgal photosynthesis is a limited but viable strategy for $CO_2$capture from flue gases produced by stationary combustion sources.

Permeability Study of Membranes for Separation $H_2$ in Oil (가스센서를 이용한 변압기 절연유중 가스 검출장치의 수소 가스 감지 특성에 관한 연구)

  • Whang, Kyu-Hyun;Seo, Ho-Joon;Rhie, Dong-Hee
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.1845-1847
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    • 2004
  • In oil-filled equipment such as transformers, partial discharge or local overheating will precede a final shutdown. Accompanied with such problems is a decomposition of insulating material into gases, which are dissolved into the transformer oil. The gases dissolved in oil can be separated with some membranes based on the differences in permeability of membranes to different gases. This paper discuss the permeability characteristics of several membranes for separation hydrogen gas in oil. With result of this paper, it may become possible to detect fault-related gases from transformer oil and predict incipient failures in the future.

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