• 대한화학회지
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• 제35권4호
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• pp.308-315
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• 1991

단순한 쿨롱액체들의 채심입방정계의 구조와 열역학적 성질들은 일성분 플라즈마에 대한 섭동론으로부터 계산된다. 섭동론(PT)과 Monte Cario(MC) 데이타의 비교는 좋은 일치를 보인다. 강체구 섭동론은 일성분 플라즈마 같은 먼 거리의 인력계에 적절하다. PT와 MC 데이타에 대한 동경 분포함수(g(r))와 구조인자(S(q))의 비교에서 일치를 보인다. 따라서 섭동론은 쿨롱액체의 성질 및 구조를 설명하는데 유용한 방법이다.

• 설비공학논문집
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• 제23권10호
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• pp.662-669
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• 2011

A numerical study was performed for thermodynamic efficiencies of a basic ORC (Organic Rankine Cycle), ORC with a FLH (Feed Liquid Heater), and ORC with a regenerator. The efficiencies of the basic ORC were higher in the order of R113, R123, R245ca, and R245fa for its working fluids. It was confirmed that an optimal FLH pressure existed to maximize efficiency of the ORC with a FLH. A correlation was developed to predict the optimal FLH pressure as a function of evaporation and condensation pressure and its average absolute deviation was 0.505%. The efficiency enhancement of the basic ORC with a FLH was higher than that with a regenerator. It was presented that the basic ORC efficiency could be improved more than 10% by a FLH with $30^{\circ}C$ condensation and over $110^{\circ}C$ evaporation temperatures.

• 대한금속재료학회지
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• 제50권1호
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• pp.45-51
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• 2012

Thermodynamics of carbon in manganese alloy melts is important in manufacturing low carbon ferromanganese and silico-manganese alloys. In order to predict the carbon solubility in liquid $Mn-Si-Fe-C_{sat}$ alloys as a function of melt composition and temperature, thermodynamic interactions among carbon, silicon and iron in carbon saturated liquid manganese should be known. In the present study, the effects of silicon and iron on the carbon solubility in Mn-Si, Mn-Fe and Mn-Si-Fe melts were measured in the temperature range from 1673 to 1773 K. The carbon solubility decreases significantly as silicon and iron contents increase in liquid manganese alloy. The interaction parameters among carbon, silicon and iron in carbon saturated liquid manganese were determined from the carbon solubility data and the Lupis' relation for the interaction coefficient at constant activity.

• The Korean Journal of Ceramics
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• 제4권2호
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• pp.61-67
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• 1998

The significance of point defects as relevant centers concerning electrochemical function is highlighted. Starting from the most simple case of dilute equilibrium bulk defect chemistry, influence of defect interaction and in particular the impact of interfaces on point defect redistribution are considered. Then recent progress in the field of kinetics in bulk and at boundaries is discussed. Finally, selected applications with emphasis on battery and sensor technology are presented.

• 오토저널
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• 제6권1호
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• pp.46-54
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• 1984

We applies Molecular Dynamics simulation technics to a system of Lennard-Jones potential interacting Argon liquid to study shear flow behavior. The thermodynamic state of the system is .rho.=35.54 Kg, mole/m$^{3}$, T=86.5.deg. K which is the triple point of Argon liquid. We applies shear rate : .epsilon.=9.26*10$^{9}$ 1/sec in the system. We find the response function, shear viscosity changes, and shear rate build-up as a function of time. We also find the thermal conductivity in a soft-sphere system.

• 대한화학회지
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• 제7권2호
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• pp.179-181
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• 1963

The partition function of liquid halogens is developed applying the significant liquid structure theory proposed by H. Eyring and co-workers. The parameters in the partition function are determined by triple point technique which was proposed by the authors in the previous paper, and also the thermodynamic properties and the surface tension are calculated by the method therein.

• 대한화학회지
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• 제7권2호
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• pp.174-178
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• 1963

The new method to determine the parameters in the liquid partition function of H. Eyring and co-workers is proposed, in which method the equilibrium condition of the three phases and the boundary condition of the liquid partition function at the triple point are used. The calculated thermodynamic properties using the new determined parameters are agreed well with the observed values.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1667-1670
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• 2009

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.652-657
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• 2007

This paper is an interim report on the investigation of thermodynamic properties of $CO_2$/oil mixture refrigerant. First, liquid density of POE (poly-ol ester) and PAG (poly alkylene glycol) were measured and expressed as a function of temperature. Then, a solubility equation was developed which enables us to calculate the weight fraction of $CO_2$ for the mixture in a liquid state. An experimental apparatus with a cell was constructed to measure P-$\upsilon$-T-$\chi$ data for $CO_2$/oil mixture. The volume of the cell was determined using a certain formula considering change in volume as a function of temperature and pressure. Then, experimental data were obtained over the temperatures $40^{\circ}C$, $50^{\circ}C$, $60^{\circ}C$, $70^{\circ}C$ and $80^{\circ}C$ with various mole fractions. Finally, assuming a primitive model of ideal gas, the volume of $CO_2$/oil mixture was predicted with a relatively larger error of 5.05% for $CO_2$/PAG and 8.81% for $CO_2$/POE. The volume of $CO_2$/oil mixtures would be better predicted using an appropriate equation of state, of which results will be reported soon.

• Korean Chemical Engineering Research
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• 제61권1호
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• pp.116-122
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• 2023

열역학 계를 구성하는 분자들의 특성, 거시적 규정의 성분, 상의 종류가 엔트로피에 미치는 관련성을 고찰하였다. 같은 성분에 속하는 분자들의 불구별성에 대하여 고전역학과 양자역학의 관점의 차이를 이해하고, 분자의 특성이 거시적 분류의 기준인 '성분'과 부합하는가를 검토하였다. 계의 열역학적 미시 상태에 관한 정의를 명확히 함으로써 분자의 구별성에 기인하는 볼츠만 통계학의 결함을 제거하고, 그 결과로 엔트로피에 대한 깁스 역설이 해소된다. 유체 및 고체의 상 변화에서 분자의 불구별성, 대칭수, 그리고 실현되는 미시 상태들의 수의 변화가 분배 함수와 엔트로피에 미치는 영향을 고찰하였다. 특히, 결정성 고체는 에르고딕 가설을 따르지 않는 열역학 계로 다룰 수 있음을 보인다.