• 제목/요약/키워드: deposition parameter

검색결과 214건 처리시간 0.025초

Fluidized Bed에서 화학증착법에 의해 증착된 열분해 탄소의 특성 (The Characteristics of Pyrolytic Carbon Deposited in a Fluidized Bed by CVD)

  • 승성표;이재영;진억용
    • 한국세라믹학회지
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    • 제21권2호
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    • pp.156-164
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    • 1984
  • The characteristic of pyrolytic carbon deposited in a fluidized bed as measured by density apparent crystallite size and viewed metallographically under polarized light can be easily controlled by adjusting the deposition parameters such as deposition temperature and propane flow rate or silicon content. The density of isotopic pyrolytic carbons deposited from propane between 120$0^{\circ}C$ and 140$0^{\circ}C$ increases with increasing propane flow rate and decreasing deposition temperature from 1, 73g/cc to 2.08g/cc. The apparent crystallite size Lc parameter appears to depend only on deposition temperature being entirely independent of the propane flow rate. The carbon matrix density of the silicon-alloyed carbonds deposited from propane and methyltrichlorosil-ane from 2.05g/cc for a silicon content around 9wt% to 2.67g/cc for a silicon content of 36.7wt% The Lc parameter of the deposition temperature being entirely independent of the silicon content.

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총괄 변수 모델을 이용한 DPF 재생 성능에 관한 연구 (A Study on the Regeneration Performance of DPF using Lumped Parameter Model)

  • 전문수
    • 융복합기술연구소 논문집
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    • 제1권1호
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    • pp.41-47
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    • 2011
  • With the world-wide demand on the emission minimization, the needs on the diesel aftertreatment devices with high efficiency are also increasing. In order to effectively develop or design a high-performance diesel particulate filter, a clear understanding on the deposition and regeneration mechanism is required. In the present study, a theory on the lumped parameter model for wall-flow type diesel particulate filters is described focusing on the deposition efficiency, pressure drop inside the filter. The fourth order explicit Runge-Kutta method is utilized for the mass flow rate computation. Engine operation modes with controlled and uncontrolled regeneration options are selected. The computational lumped parameter model is validated by comparing the computed results with the measured data.

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각기 다른 단백질섭취 수준에서 본 식이단백질의 질이 단백질대사에 미치는 영향 -Simulation Model을 이용하여- (Simulation of the Effect of Protein Quality at the Different Protein Intake Level on Protein Metabolism)

  • 이옥희
    • Journal of Nutrition and Health
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    • 제26권9호
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    • pp.1033-1048
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    • 1993
  • This study was designed to describe the effect of the protein quality at different intake level of protein on the protein metabolism in the whole body of growing pigs with a simulation model. Varying to the protein level in feeds, four simulations were conducted. The feed protein level, represented as proportions of digestible protein to the metabolic energy (DP/ME, g/MJ), were 6-8, 11-13, 17-19, and 23-25 DP/ME, respectively. Two protein quality and six weeks of growth time were used at each simulation. The objective function for the simulations was protein deposition in the whole body, which was calculated from the experimental results. The parameters in the simulation were determined by the parameter estimation technique. The results obtained from the simulation were as follows: The protein synthesis and breakdown rates(g/day) in the whole body was increased with the increase of protein quality only at lower or required level of protein intake. They showed a parallel behavior in the course of growth, irrespective of quality and level of feed protein intake. The simulated protein deposition and protein synthesis showed a linear relationship between them at different protein quality and level. The affinity parameter showed a linear relationship between them at different protein quality and level. The affinity parameter showed that arginine, tryptophan and isoleucine were more efficient in the stimulation ofbody protein synthesis. Lysine and phenylalanine+tyrosine were less efficient. The oxidation parameter showed that histidine, pheyalanine+tyrosine were less efficient. The oxidation parameter showed that histidine, phenyalanine+tyrosine, and methionine+cystine were oxidized in larger magnitude than lysine and threonine. The oxidation parameter of most amino acids increased with the increase of protein intake beyond the requirement level, but not any more at highest protein intake level. Finally it was found that the improvement of feed protein quality at the lower or required level of protein intake increase protein deposition through a parallel increase of protein synthesis and breakdown.

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TiO2 박막의 증착거동에 미치는 스퍼터링 공정변수의 영향 (Effect of Sputtering Parameter on the Deposition Behavior of TiO2 Thin Film)

  • 김을수;이건환;권식철;안효준
    • 한국수소및신에너지학회논문집
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    • 제14권1호
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    • pp.8-16
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    • 2003
  • $TiO_2$ thin films were deposited by DC reactive magnetron sputtering with variations in sputtering parameter such as Ar and $O_2$ flow rate, DC power, substrate temperature and magnetic field. Deposition rate, crystal structure, chemical bond of $TiO_2$ films on the deposition conditions were investigated by Alpha-step, X-ray Diffractometer(XRD), X-ray Photoelectron Spectroscopy(XPS). When the DC power was applied at 500watt, deposition rate of $TiO_2$ film was about 480A/min. $TiO_2$ films coated under the deposition condition of 15sccm Ar and 7~10sccm $O_2$ flow rate was only observed anatase phase. With increasing substrate temperature from RT to $300^{\circ}C$, crystal orientation of $TiO_2$ films variously became.

정전기 분무 증착법에 대한 최근 연구 동향 고찰 (Research Issues of Electrostatic Spray Deposition (ESD) Technique)

  • 류성욱;이상용
    • 한국분무공학회지
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    • 제11권1호
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    • pp.7-16
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    • 2006
  • Performance of thin films fabricated with the electrostatic spray deposition (ESD) technique is strongly governed by surface morphology, which depends on deposition parameters such as deposition time and temperature, solution properties, and surface characteristics of substrates. In this article, the state of the art on the relationships between the surface morphology and the deposition parameters is presented. Also studies on the electro-hydrodynamic atomization process and the motion of drops relevant to the ESD technique are briefly reviewed, and the future research works are suggested.

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초음파 풍속온도계를 이용한 $SO_2$건성침착속도의 계절변화 특징 (Seasonal Variations of $SO_2$Dry Deposition Velocity Obtained by Sonic Anemometer-Thermometer)

  • 이종범;박세영
    • 한국대기환경학회지
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    • 제14권5호
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    • pp.465-478
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    • 1998
  • In this study, seasonal variations of the dry deposition velocity and deposition flux for the sulfur dioxide were analysed. The field observation was performed during one year (from November 1, 1995 to October 31, 1996) in Chunchon basin. The turbulence data were measured by 3-dimensional sonic anemometer/thermometer, and were estimated by mean meteorological data obtained at two heights (2.5 m and 10 m) of meteorological tower. Also, the estimation methods were evaluated by comparing the turbulence data. The results showed that the estimated dry deposition velocity and turbulence parameter such as uc and sensible heat flux using mean meteorological data were relatively similar to the sonic measurements, but all showed somewhat large differences. The dry deposition velocity was large in summer and small in winter mainly due to canopy resistance (rc). The major factor which affects diurnal variation of the velocity was aerodynamic resistance (rw). The SO2 dry deposition flux was large in winter and small in summer in Chunchon.

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분말송급 및 와이어송급을 이용한 레이저 클래딩 특성 (Comparison of Powder Feeding and Wire Feeding in Laser Cladding)

  • 안영남;김철희
    • Journal of Welding and Joining
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    • 제31권4호
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    • pp.13-16
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    • 2013
  • In this research, laser cladding characteristics were investigated for various filler metal feeding methods such as powder, cold wire, and hot wire feeding. Appropriate parameter window, deposition rate, material efficiency and dilution for each filler feeding method were evaluated with same laser power and cladding speed range. Laser powder cladding has wider process parameter window but higher material efficiency and lower dilution were achieved by laser wire cladding. Among these feeding methods, laser hot-wire cladding showed best efficiency in material usage and deposition rate.

수치모델을 이용한 ICP-CVD 장치의 증착 균일도 해석 (Numerical Modeling of Deposition Uniformity in ICP-CVD System)

  • 주정훈
    • 한국표면공학회지
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    • 제41권6호
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    • pp.279-286
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    • 2008
  • Numerical analysis is done to investigate which would be the most influencing process parameter in determining the uniformity of deposition thickness in TiN ICP-CVD(inductively coupled plasma chemical vapor deposition). Two configurations of ICP antenna are modeled; side and top planar. Side and top gas inlets are considered with each ICP antenna geometries. Precursor for TiN deposition was TDMAT(Tetrakis Diethyl Methyl Amido Titanium). Two step volume dissociation of TDMAT is used and absorption, desorption and deposition surface reactions are included. Most influencing factors are H and N concentration dissociated by electron impact collisions in plasma volume which depends on the relative positions of gas inlet and ICP antenna generated hot plasma region. Low surface recombination of N shows hollow type concentration, but H gives a bell type distribution. Film thickness at substrate edges is sensitive to gas flow rate and at high pressures getting more dependent on flow characteristics.

구형파 펄스를 인가한 정전분무 장치의 대전량 특성 (Charging Characteristics of Electrostatic Sprayer Applied Square Pulse)

  • 박승록;문재덕
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제52권12호
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    • pp.573-578
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    • 2003
  • In this study, new type of induction charging system for electrostatic spraying was manufactured and proposed to improve the electrical safety and charging efficiency. And parameters of proposed system to generate the maximum deposition current with electrical safety were selected and investigated. The selected parameters were frequency of square pulse and thickness of insulation material, outer diameter of device and thickness and positions of electrode. Charging quantity of water drop was measured by deposition current detected from sensing plate indirectly. The maximum deposition current for each parameter were 3.5[uA] at the frequency of 15[kHz] and thickness of 0.25[mm] insulating layer. And maximum deposition currents were 2.8[uA] and 3.0[uA] at 25[mm] outer diameter of charging device and 0.25[mm] thickness of electrode each. Effects of electrode position from spraying nozzle on deposition current was a little.