• Title/Summary/Keyword: equilibrium data

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The prediction of vapor-liquid equilibrium data for 2-methyl-2-propanol-2-butanone system at low pressure (저압하에서 2-methyl-2-propanol-2-butanone계의 기액평형치의 추산)

  • Shim, Hong-Seub;Rhew, Jong-Ha
    • Journal of the Korean Society of Industry Convergence
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    • v.7 no.1
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    • pp.97-105
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    • 2004
  • The Vapor-liquid equilibrium data for the binary system of 2-methyl-2-propanol-2-butanone are measured at subatmospheric pressure of 100, 200, 300, 400, 500, 600, 700 and 760 torr. This study shows that the relations between logarithmic values of relative valatility(log ${\alpha}$)and liquid phase composition(${\chi}$) in the above binary systems are expressed as a linear function. When the linear relationships of between logarithmic values of relative volatilities and liquid phase compositions in the binary systems of various pressure intersect at a point, this empirical equation can be applied to the systems of this kind. From these relations the vapor-liquid equilibrium data are estimated and compared with the measured values to be in a good agreement with in accuracy ${\pm}0.0021$ for the various pressure.

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Correlation of Liquid-Liquid Equilibrium of Four Binary Hydrocarbon-Water Systems, Using an Improved Artificial Neural Network Model

  • Lv, Hui-Chao;Shen, Yan-Hong
    • Journal of the Korean Chemical Society
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    • v.57 no.3
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    • pp.370-376
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    • 2013
  • A back propagation artificial neural network model with one hidden layer is established to correlate the liquid-liquid equilibrium data of hydrocarbon-water systems. The model has four inputs and two outputs. The network is systematically trained with 48 data points in the range of 283.15 to 405.37K. Statistical analyses show that the optimised neural network model can yield excellent agreement with experimental data(the average absolute deviations equal to 0.037% and 0.0012% for the correlated mole fractions of hydrocarbon in two coexisting liquid phases respectively). The comparison in terms of average absolute deviation between the correlated mole fractions for each binary system and literature results indicates that the artificial neural network model gives far better results. This study also shows that artificial neural network model could be developed for the phase equilibria for a family of hydrocarbon-water binaries.

Phase Equilibrium of Binary Mixture for the (propylene oxide + 1-pentanol) System at Several Temperatures

  • Kim, Jeong-lae;Kim, Hakmin;Park, Su In;An, Gyu Min;Kim, Min Gi;Shin, Moon Sam
    • Korean Chemical Engineering Research
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    • v.57 no.1
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    • pp.73-77
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    • 2019
  • Isothermal (vapor + liquid) equilibrium data measurements were undertaken for the binary mixtures of (propylene oxide + 1-pentanol) system at three different temperatures (303.15, 318.15, and 333.15) K. The Peng-Robinson-Stryjek-Vera equation of state (PRSV EOS) was used to correlate the experimental data. The van der Waals one-fluid mixing rule was used for the vapor phase and the Wong-Sandler mixing rule, which incorporates the non-random two liquid (NRTL) model, the universal quasi-chemical (UNIQUAC) model and the Wilson model, was used for the liquid phase. The experimental data were in good agreement with the correlation results.

Pridiction of Adsorption Equilibrium for Binary Gas Mixtures on Cation Exchanged Forms of ZSM-5

  • Going Yim;Chai Suck Yim
    • The Journal of Engineering Research
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    • v.6 no.2
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    • pp.85-98
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    • 2004
  • The adsorption equilibrium data for the binary gas mixture system from the pure gas adsorption data of carbon dioxide and ethylene on ZSM-5 prepared were predicted. The binary gas mixture adsorption data have been examined against predicted values by two models-the vacancy solution model(VSM) and the statistical thermodynamic model(STM), using parameters obtained from the single component isotherm. The binary gas mixture data for the carbon dioxide-ethylene system were obtained for cation exchanged forms of ZSM-5 for the gas phase carbon dioxide mole fraction of 0.752 at $37^{\circ}C$ and 1 atm. The experimental adsorption phase diagrams were obtained for carbon dioxide-ethylene on sodium form ZSM-5 synthesized. The single component adsorption isotherms for carbon dioxide and ethylene were also obtained for this zeolite. The single component data were used to obtain parameters derived in two models. These parameters were, in turn, used to predict the binary mixture isotherms for this zeolite. Both the vacancy solution and the statistical thermodynamic models give satisfactory predictions of adsorption phase diagrams for the binary gas mixtures of carbon dioxide and ethylene on sodium exchanged ZSM-5. Also the correlation between the experimental data and the predicted values is generally in good agreement. The system appears to show ideal behavior with a relatively constant separation factor. The slight increase in adsorption capacity with an increase in ionic radius is due, in part, to the higher polarizability associated with larger cations.

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Hypersonic Viscous Interaction of Wedge Flows (극초음속 쐐기 유동의 Viscous Interaction)

  • Kim K. H.;Rho O. H.
    • 한국전산유체공학회:학술대회논문집
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    • 1996.05a
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    • pp.40-45
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    • 1996
  • This paper discribes the viscous interaction of Hypersonic Wedge Flows using Roe FDS and AUSM+. For this purpose we developed the frozen and the equilibrium code and numerically simulated the viscous interaction by changing the surface temperature and the mach number. We used curve fitting data in NASA Reference Publication 1181, 1260 to calculate equilibrium properties. We compare the equilibrium flow with the frozen flow. We conclude that the mach number and the surface temperature are significant parameters, as the surface temperature and the mach number increase the viscous interaction becomes stronger, and we must consider high-temperature effects in hypersonic flow

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Application of Multigrid Method for Computing Hypersonic, Equilibrium Flows (다중격자 기법을 적용한 극초음속 평형 유동장 계산)

  • Kim Sung soo;Kim Chongam;Rho Oh-Hyun
    • 한국전산유체공학회:학술대회논문집
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    • 1999.05a
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    • pp.23-28
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    • 1999
  • A mutigrid convergence acceleration technique is presented for computing hypersonic inviscid and viscous flows in equilibrium state. The governing equations are solved using an explicit Runge-Kutta method. Curve fitting data in NASA Reference Publication 1181, 1260 are used to calculate equilibrium properties. In order to ensure stability, damped prolongation and modified implicit residual smoothing are proposed. Blunt body test cases are presented to demonstrate the robustness and the efficiency in performance of the proposed methods

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The Prediction of Vapor-Liquid Equilibrium Data for Cyclohexanol-Cyclohexanone System at Subatmospheric Pressure (감압하에서 2성분 Cyclohexanol-Cyclohexanone계에 대한 기-액평형치의 추산)

  • Shim, Hong-Seub;Kim, Jong-Shik
    • Applied Chemistry for Engineering
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    • v.10 no.5
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    • pp.677-681
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    • 1999
  • For the binary cyclohexanol-cyclohexanone system the vapor-liquid equilibrium data, which are the necessary ones for the design of the distillation columns in separation process of volatile liquid-mixtures, are measured at subatmospheric pressure of 150, 300 and 500 mmHg. An empirical relation between logarithmic values of relative volatility(log $\alpha$) and liquid phase composition(x), which predicts the vapor-liquid equilibrium data, is obtained from above measured data of 150, 300 and 500 mmHg and the published ones of 30, 100, 200, 395 and 750 mmHg. The predicted data are compared with the measured and published ones to be in good agreement.

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Multi-Attribute Data Fusion for Energy Equilibrium Routing in Wireless Sensor Networks

  • Lin, Kai;Wang, Lei;Li, Keqiu;Shu, Lei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.1
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    • pp.5-24
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    • 2010
  • Data fusion is an attractive technology because it allows various trade-offs related to performance metrics, e.g., energy, latency, accuracy, fault-tolerance and security in wireless sensor networks (WSNs). Under a complicated environment, each sensor node must be equipped with more than one type of sensor module to monitor multi-targets, so that the complexity for the fusion process is increased due to the existence of various physical attributes. In this paper, we first investigate the process and performance of multi-attribute fusion in data gathering of WSNs, and then propose a self-adaptive threshold method to balance the different change rates of each attributive data. Furthermore, we present a method to measure the energy-conservation efficiency of multi-attribute fusion. Based on our proposed methods, we design a novel energy equilibrium routing method for WSNs, viz., multi-attribute fusion tree (MAFT). Simulation results demonstrate that MAFT achieves very good performance in terms of the network lifetime.

Isobaric vapor-liquid equilibria for ternary and each corresponding binaries of the system n.Dodecane-1.Decanol-1.Dodecanol at 15 mbar (n.Dodecane-1.Decanol-1.Dodecanol 삼성분계 및 각 이성분계의 15 mbar 정합 기액평형)

  • 박소진;이태종
    • Journal of Energy Engineering
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    • v.2 no.3
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    • pp.308-314
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    • 1993
  • Both Vapor-liquid equilibrium data and boiling temperature have been measured for ternary and each corresponding binaries of n.dodecane-1.decanol-1.dodecanol mixture under constant pressure of 15 mbar. Measured vapor-liquid equilibrium data were correlated with the conventional g$\^$E/ model ; Margules, van Laar, Wilson, NRTL and UNIQUAC equations. Binary equilibrium data were thermodynamically tested by Redlich-Kister integral method and ternary data were also qualitatively checked by two point consistency test, suggested by McDermott-Ellis. Among the binary VLE data, only the system n.dodecane-1.decanol has minimum boiling azeotrope.

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Local Thermal Equilibrium 모델에 의한 이차이온 질량분석의 정량화 방법

  • Gwak, Byeong-Hwa;Gwon, O-Jun
    • ETRI Journal
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    • v.10 no.2
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    • pp.63-69
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    • 1988
  • SIMS(Secondary Ion Mass Spectrometry) 분석 데이터의 정량화 방법으로 이온주입에 의한 실험적 접근법과 LTE(Local Thermal Equilibrium) 모델을 사용한 준이론적 접근법 2가지가 주로 논의되고 있다. 본 고에서는 LTE 모델을 사용, SIMS data를 정량화하는 방법에 대하여 기술하였으며 아울러 BASIC language로 된 간단한 LTE 프로그램을 제시하였다.

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