• Title/Summary/Keyword: hydrocarbon(s)

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Characterization and Application of DLC Films Produced by New Combined PVD-CVD Technique

  • Chekan, N.M.;Kim, S.W.;Akula, I.P.;Jhee, T.G.
    • Journal of the Korean Society for Heat Treatment
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    • v.23 no.2
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    • pp.75-82
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    • 2010
  • A new advanced combined PVD/CVD technique of DLC film deposition has been developed. Deposition of a DLC film was carried out using a pulsed carbon arc discharge in vapor hydrocarbon atmosphere. The arc plasma enhancing CVD process promotes dramatic increase in the deposition rate and decrease of compressive stress as well as improvement of film thickness uniformity compared to that obtained with a single PVD pulsed arc process. The optical spectroscopy investigation reveals great increase in radiating components of $C_2$ Swan system molecular bands due to acetylene molecules decomposition. AFM, Raman spectroscopy, XPS and nano-indentation were used to characterize DLC films. The method ensures obtaining a new superhard DLC nano-material for deposition of protective coatings onto various industrial products including those used in medicine.

Development of HC Sensor & System for Vehicles Exhaust Gas Check (HC 센서를 이용한 자동차 배기가스 감지 연구)

  • Chon, Young-Kap;Cho, Kook-Hee
    • Proceedings of the KIEE Conference
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    • 1999.11d
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    • pp.1011-1014
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    • 1999
  • An on-board monitoring system for an automobile emission gas has a test chamber remote from the automobile's engine exhaust gas stream: apparatus for supplying the chamber with sampled exhaust gases. A single hydrocarbon sensor exposed to the exhaust gas in the chamber to render a signal responsive to the hydrocarbon. The conductive ions in emission gas was checked by the HC sensor in test chamber. A preferred application includes hydrocarbons in an automotive exhaust gas stream by exposing a transition porous alumina($Al_{2}O_{3}$) ceramic based sensor to the same exhaust gas stream. By combining the electrical signal, a measure of hydrocarbons can be provided.

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The Analytical Bias of Total Hydrocarbon (THC) Measurements in Relation to the Selection of Standard Gas Compound (총탄화수소의 계측에서 표준시료성분의 선택에 따른 오차 발생 연구)

  • Kim, Ki-Hyun
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.4
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    • pp.449-452
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    • 2010
  • In this article, the performance of the THC analyzer was inspected using two different span gases of methane ($CH_4$) and propane ($C_3H_8$). To explore the effect of standard gas selection, MicroFID system was tested by the following procedures. Initially, the system is spanned by propane gas of 60 ppm (or 180 ppmC). The system is then run against methane standards prepared at 5 different concentrations of 200, 250, 300, 400, and 500 ppm. According to the suggestion of the KMOE's test procedure to use multiplying a factor of 3 (for propane), the resulting THC values derived by methane standards were systematically biased with ~500% error relative to true value. This paper discusses the interpretation procedures to obtain the least biased THC values for a given span set-up.

The hydrocarbon concentration distribution in the contaminated site using geospatial analysis

  • Lee, Ju-Young;Yang, Jung-Seok;Choi, Jae-Young;Krishinamurshy, Ganeshi
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.909-910
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    • 2007
  • The volatile organic compounds exposure is governed by the source distance and dispersion of the pollutant into air and groundwater. The purpose of this study was to validate suggested models for the prediction of concentration distributions. The study design was organized into different methods to simulate industry site. The distribution models generally showed a fair agreement with measured data. For graphical representation of concentration of volatile hydrocarbon, it has to obtain a continuous representation of the contamination of the site. Therefore, the used interpolative methods examined for this project are the IDW(inverse Distance Weighting) and kriging method. In the results, in summary, all two different methods can be used to quantify exposures at a particular source area, and thus provide, a solid foundation for making risk-based decisions. All the calculations can be performed using Excel's built-in functions, and the capabilities of geospatial analysis allow the results to be displayed visually. However, anyone who uses these methods should understand all of the assumptions and limitation.

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The Variation of Offset Ink Properties According to the Vegetable Fatty Acid Esters (Vegetable Fatty Acid Esters에 따른 평판 잉크의 물성 변화에 관한 연구)

  • Park, Jung-Min;Kim, Sung-Bin
    • Journal of the Korean Graphic Arts Communication Society
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    • v.29 no.3
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    • pp.1-16
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    • 2011
  • In these days, according to increased environmental regulations, to reduce the VOC content in paints and inks efforts are now in progress. A lot of research have progressed hydrocarbon solvents substitute with vegetable oil or ester in the printing ink but it is restricted to use vegetable oil in the inks because of high molecular weight and viscosity. Oil ester currently developed for printing inks still have some drawbacks, but overall the printability and print quality when using ester than hydrocarbon solvents are showing good results. Thus, in this paper, I studied about the properties variation of the varnish and inks according to vegetable ester, after I reacted vegetable ester using the vegetable fatty acid and ethyl alcohol, butyl alcohol. The compared in order of average molecular weight by the GPC method, rheological properties were found by rotational rheometer, and emulsion behavior were compared by high speed emulsification tester.

Application of Hydrocarbons as Markers for Detecting Post-irradiation of Imported Meats and Fish (수입육류 및 어류의 방사선조사 여부 판별을 위한 Marker로 검출되는 Hydrocarbons의 활용)

  • 황금택;박준영;김충기
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.6
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    • pp.1109-1115
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    • 1997
  • Hydrocarbons were analyzed in irradiated beef, pork, dried and seasoned beef, dried anchovy, dried squid, dried shrimp, and fish paste to determine whether the hydrocarbons can be used as markers for detecting post-irradiation of the imported meat and fish products. The samples were irradiated at 0.5, 1, 3, and 6 kGy. Fat was extracted with hexane, and hydrocarbons were separated from the fat through Florisil column. The hydrocarbons were analyzed with GC. Hydrocarbons 15:0, 16:1, 17:1, 16:2, 17:2, and 16:3 in beef and pork, 17:1, 16:2, and 17:2 in dried and seasoned beef, 16:2 in dried anchovy, 16:1 and 17:1 in dried squid, 16:1, 17:1, and 16:2 in dried shrimp, and 16:1, 16:2, and 16:3 in fish paste were detected in the irradiated samples, but not in the unirradiated, so that the hydrocarbons may be used as makers for detecting post-irradiation of each item.

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Transient Absorption Spectra of Phenothiazine Derivative in the Vesicle System Containing Ru$^{2+}$ Complex as a Sensitizer

  • Park, Yong-Tae;Kim, Young-Doo;Burkhart, Richard D.;Caldwell, Norris J.
    • Bulletin of the Korean Chemical Society
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    • v.9 no.2
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    • pp.84-87
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    • 1988
  • The Photophysical and photochemical properties of Ruthenium bipyridine with two long hydrocarbon chains, $[Ru(bipy)_2(dhbipy)]^{2+}$ and transient phenothiazine derivative cation radical $(PTD^+)$ in the cationic vesicle were studied. Transient absorption spectra of cation radical of phenothiazine derivative in the vesicle system containing the $Ru^{2+}$ complex, $[Ru(bipy)_2(dhbipy)]^{2+}$, (1) as sensitizer and phenothiazine derivative as electron donor was observed by XeCl excimer laser photolysis system. Thus the excited ruthenium complex would be quenched by phenothiazine derivative(PTD) reductively in the vesicle system. The quenching rate constant($K_Q$) of $Ru^{2+}$ with two long hydrocarbon chains in the vesicle by PTD was $9.6{\times}10^8M^{-1}S^{-1}$. The absorption decay kinetics showed that lifetime of phenothiazine derivative cation radical is a value in the 4-8m sec range.