• Title/Summary/Keyword: Equilibria

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Environment Policy and Regional Economic Growth: Conflicting vs. Complementing (환경정책과 지역경제 : 상반관계 vs. 보완관계)

  • 김홍배;윤갑식
    • Journal of the Korean Regional Science Association
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    • v.15 no.1
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    • pp.63-73
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    • 1999
  • It is generally believed that there is a trade-off between economic growth and environmental quality since pollutants are generated in the process of production and consumption of commodities. Several researchers have shown this prevailing belief using the short-term input-output models. The literature, however, shows that there have been few attempts to investigate the relationship using long-term forecasting models. This motivates the current paper. This paper attempts to build a reginal growth model in a partial equilibrium framework taking into consideration the requirements of capital invested for pollutant abatement. Model is largely neoclassical. Labor is assumed to move a region with high utility specified in regional per capita average was income and pollution level while capital is partially mobile to a region with high returns. The regional growth is explored in a phase diagram. The paper shows that there are two stable growth equilibria which a region can converge over time and that the equilibria are distinguished by the initial threshold capital stock that a region holds. If the initial capital stock of a region is over(under) than the threshold size, the region converges to the higher (lower) growth equilibrium over time. Moreover, based on this result an environmental quality enhancing policy is analyzed in the phase diagram. It has revealed that the policy calls for the relocation of growth equilibrium points, specifically speaking, it stimulates an increase in labor stock and a decrease in capital stock. Hence the paper has suggested that the prevailing belief which the environmental policy negatively impacts on a regional economic growth is not always true.

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An Experimental Study on Vapor-Liquid Equilibria of $CO_2$/Oil Mixtures in the Range of Evaporator Working Pressure (증발기 작동 압력 범위에서 $CO_2$/오일 혼합물의 기상-액상 평형 실험)

  • Lee, Chi-Seok;Lee, Kyoung-Youl;Kang, Byung-Ha;Park, Kyoung-Kuhn
    • Proceedings of the SAREK Conference
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    • 2005.11a
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    • pp.380-385
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    • 2005
  • An experimental apparatus was constructed to obtain vapor-liquid equilibrium data for $CO_2$/oil mixtures using mass analysis method with sample cylinder. Lubricants employed were POE(Polyol Ester) oil and PAG(Poly Alkylene Glycol) oil. The phase equilibria of $CO_2$/oil mixtures formed in high pressure equilibrium cell are observed through sight glasses at the opposite ends. Data were measured over the temperature range from -10 to $10^{\circ}C$ with $5^{\circ}C$ intervals under pressures up to 14 MPa. Mole fractions were calculated for $CO_2$/oil and $CO_2$/PAAG, respectively and were compared with each other.

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Investigation of Demixing Phenomena of a Polymer Solution During the Phase Inversion Process

  • Han, Myeong-Jin;D. Bhattacharyya
    • Proceedings of the Membrane Society of Korea Conference
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    • 1995.04a
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    • pp.11-15
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    • 1995
  • Polysulfone (PS) membranes were prepared by the phase inversion process using water or isopropanol as nonsolvent. The Flory-Huggins theory for a ternary system nonsolvent/solvent/polymer is applied to describe the thermodynamic equilibria of the components. The calculated ternary phase equilibria show that demixing of a PS binary solution with n-methylpyrrolidone (NMP) will be fast in a water coagulation bath and will be delayed in an isopropanol bath. The prepared membranes were characterized by SEM, gas adsorption-desorption measurement, and permeability test. The membrane, which is precipitated by fast demixing in a water bath, has nodular structures in the skin region and includes finger-like cavities in the sublayer. The membrane coagulated by isopropanol has a very dense and thick skin structure, which is formed by delayed demixing. The membrane coagulated by isopropanol showed considerably lower pore volume and surface area compared to that observed with water coagulation method. With dimethylformamide (DMF) as solvent and 2-3 wt% of water, the solution can show the liquid-liquid phase separation due to agglomation of the polymer-lean phase from the homogeneous solution. The membranes, which were coagulated near an equilibrium state, show the large (micron size) round pores in the whole membranes. The pores do not contribute the permeation characteristics.

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A Non-cooperative Game Theoretic Approach to Dust and Sand Storm in North East Asia

  • Song, Yang-Hoon
    • Journal of Environmental Policy
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    • v.6 no.3
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    • pp.91-114
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    • 2007
  • The cooperative cost sharing scheme for Dust and Sand Storm(DSS) in North East Asia, as suggested in Song and Nagaki(2007), may not be feasible due to possible defection(s) of participating countries. If non-cooperative strategies are more plausible, Nash equilibrium can suggest possible outcomes of the cost sharing game. The result from the continuous strategy model shows that there exists an infinite number of Nash equilibrium such that the summation of investment from each country is always equal to the required budget of the ADS pilot project. It is also discussed that the discrete strategy model points to only 3 Nash equilibria in continuous strategy game outcome and the cooperative game solution may be just one of the infinite equilibria.

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Correlation between Determining Values of Sectional Equilibrium Moisture Contents of Larix leptolepis and Populus euramericana I - 476 grown in Mt. Jiri (지리산산(智異山産) 일본 잎갈나무재(材)와 포플러재(材)의 단면별(斷面別) 평형함수율(平衡含水率)(EMC) 측정치(測定値)와 그 상관성(相關性))

  • Hwang, Jeung;Moon, Chang Kuck
    • Journal of Korean Society of Forest Science
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    • v.59 no.1
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    • pp.63-66
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    • 1983
  • Sectional equilibrium moisture contents of Larix leptolepis and Populus euramericana I-476 were determined, their correlations and significances were investigated. Among the ovendry moisture contents. electric moisture meter determining values and the estimative values through chemical equilibria formula, there were significant correlations, 1-5% level, at whole sections in Larix leptolepis. However, in Populus euramericana there was only significant correlation between ovendry moisture content values and electric moisture meter determining values.

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Vapor-Liquid Equilibria of Carbon Dioxide and Propane Mixtures (이산화탄소와 프로판 혼합냉매의 기상-액상 평형)

  • Kim, Ju-Hyok;Kim, Min-Soo;Kim, Man-Hoe
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.11
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    • pp.859-866
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    • 2006
  • This paper presents the vapor-liquid equilibrium (VLE) data measured for carbon dioxide and propane mixtures. Their mixtures were considered as promising alternative refrigerants due to good thermophysical properties and negligible environmental impact. The isothermal VLE data were measured at eight temperatures ranging from 253.15 to 323.15 K in the circulation type equipment with a view cell. The binary system was found to be a zeotropic mixture in the tested temperature range and could be correlated with sufficient accuracy by using the Peng-Robinson equation of state (PR EoS) with the van der Waals one fluid mixing rule. A comparison with published experimental VLE data has been carried out by means of the PR equation of state. In addition, the phase behaviors of carbon dioxide and propane mixtures were analyzed based on the measured VLE data.

Integrated Thermochemical Approach to Collision-Induced Dissociation Process of Peptides

  • Shin, Seung Koo;Yoon, Hye-Joo
    • Mass Spectrometry Letters
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    • v.12 no.4
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    • pp.131-136
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    • 2021
  • Collision-induced dissociation of peptides involves a series of proton-transfer reactions in the activated peptide. To describe the kinetics of energy-variable dissociation, we considered the heat capacity of the peptide and the Marcus-theory-type proton-transfer rate. The peptide ion was activated to the high internal energy states by collision with a target gas in the collision cell. The mobile proton in the activated peptide then migrated from the most stable site to the amide oxygen and subsequently to the amide nitrogen (N-protonated) of the peptide bond to be broken. The N-protonated intermediate proceeded to the product-like complex that dissociated to products. Previous studies have suggested that the proton-transfer equilibria in the activated peptide affect the dissociation kinetics. To take the extent of collisional activation into account, we assumed a soft-sphere collision model, where the relative collision energy was fully available to the internal excitation of a collision complex. In addition, we employed a Marcus-theory-type rate equation to account for the proton-transfer equilibria. Herein, we present results from the integrated thermochemical approach using a tryptic peptide of ubiquitin.

Spectroscopic Identifications and Phase Equilibria of THF + 3-OH THF + CH4 Clathrate Hydrates (삼성분계 THF + 3-OH THF + CH4 크러스레이트 하이드레이트의 상평형 거동 해석 및 분광학적 분석)

  • Kim, Heejoong;Ahn, Yun-Ho;Moon, Seokyoon;Hong, Sujin;Park, Youngjune
    • Korean Chemical Engineering Research
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    • v.55 no.3
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    • pp.353-357
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    • 2017
  • In this study, the inclusion phenomena of tetrahydrofuran + 3-hydroxytetrahydrofuran + $CH_4$ clathrate hydrates were explored via thermodynamic and spectroscopic approaches. The phase equilibria of the double hydrates - THF + $CH_4$ and 3-OH THF + $CH_4$ clathrate hydrates - were determined by pressure-temperature trace during hydrate formation and dissociation, and the result revealed that the equilibrium pressures were shifted to lower pressure region compared to pure $CH_4$ hydrate. The powder X-ray diffraction patterns revealed that the double hydrates of THF + 3-OH THF formed structure II type clathrate hydrates with $CH_4$. The dispersive Raman spectra of the double clathrate hydrates also exhibited that $CH_4$ can be trapped in both $5^{12}6^4$ and $5^{12}$ cages whereas THF and 3-OH THF were encaged in $5^{12}6^4$ cage.

Effect of Redox Processes and Solubility Equilibria on the Behavior of Dissolved Iron and Manganese in Groundwater from a Riverine Alluvial Aquifer (만경강 하천변 충적 지하수의 용존 Fe와 Mn 거동에 대한 산화-환원 과정과 용해 평형의 효과)

  • Choi, Beom-Kyu;Koh, Dong-Chan;Ha, Kyoo-Chul;Cheon, Su-Hyun
    • Economic and Environmental Geology
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    • v.40 no.1 s.182
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    • pp.29-45
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    • 2007
  • Biogeochemical characteristics involving redox processes in groundwater from a riverine alluvial aquifer was investigated using multi-level monitoring wells (up to 30m in depth). Anaerobic conditions were predominant and high Fe ($14{\sim}37mg/L$) and Mn ($1{\sim}4mg/L$) concentrations were observed at 10 to 20 m in depth. Below 20 m depth, dissolved sulfide was detected. Presumably, these high Fe and Mn concentrations were derived from the reduction of Fe- and Mn-oxides because dissolved oxygen and nitrate were nearly absent and Fe and Mn contents were considerable in the sediments. The depth range of high Mn concentration is wider than that of high Fe concentration. Dissolved organics may be derived from the upper layers. Sulfate reduction is more active than Fe and Mn reduction below 20 m in depth. Disparity of calculated redox potential from the various redox couples indicates that redox states are in disequilibrium condition in groundwater. Carbonate minerals such as siderite and rhodochrosite may control the dissolved concentrations of Fe(II) and Mn(II), and iron sulfide minerals control for Fe(II) where sulfide is detected because these minerals are near saturation from the calculation of solubility equilibria.

Liquid-Liquid Equilibria of Poly(4-vinylphenol)(PVPh)/Ethyl Acetate and PVPh/Butyl Acetate Solutions (Poly(4-vinylphenol)(PVPh)/Ethyl Acetate 및 PVPh/Butyl Acetate 용액계의 액-액 상평형)

  • Kim, Mi Kyung;Kim, Ki-Chang
    • Korean Chemical Engineering Research
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    • v.43 no.6
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    • pp.704-714
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    • 2005
  • Phase separations of Poly(4-vinylphenol)(PVPh)/Ethyl Acetate and PVPh/Butyl Acetate solutions were measured using the thermal optical analysis (TOA) method. The experimental phase separation data were correlated with liquid-liquid equilibria relations based on PC-SAFT equation of state. The phase separations of these system showed the behaviors of LCST (lower critical solution temperature)-type. The measured cloud temperatures were lowered with increasing in molecular weights of polymer(PVPh), and cloud temperatures of PVPh/Ethyl Acetate solutions shifted to lower temperature regions, compared to the PVPh/Butyl Acetate solutions. Extents of cross-association between solvent molecule and polymer in the PVPh/Ethyl Acetate solutions were measured using the FT-IR spectrum analysis method, and cross-association parameters of PC-SAFT model were estimated from experimental extents of cross-association. By using the estimated cross-association parameters between PVPh and solvent molecule, binodal and spinodal curves of liquid-liquid equilibria in PVPh/Ethyl Acetate and PVPh/Butyl Acetate solutions were calculated from PC-SAFT equation of state. The calculated binodal curves of these system were shown to be well agreeable with the experimental cloud temperature curves.