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In this article, new Gibbs free energy of mixing is derived when there are specific interactions between sol- vent-solute molecules and between solute-solute molecules in binary solutions. It is asssumed that a probability of specific interactions satisfies a binomial distribution. Using this Gibbs free energy of mixing, we investigate possible types of partial miscibilities and show that Ω-shaped temperature-composition phase diagrams can exist. We calculate Ω-shaped temperature- composition phase diagram of water-2-butanol system and compare that with result calculated by the method of Hino 5 et al.

In some binary solution, closed miscibility loop of temperature-composition phase diagram occurs where both an upper critical solution temperature and a lower critical solution temperature exist. It is known that this phenomena occurs if specific interaction between molecules exists. There are several ways describing the specific interaction. In this work it is assumed that the total number of specific interactions is distributed according to binomial distribution. In this case, exact mathematical conditions for closed miscibility loop phase behavior are derived when the specific interaction is applied to reg- ular solution theory, quasichemical theory and Flory-Huggins lattice theory. And we investigated the effect of parameters on the phase diagram. The phase diagram of water-nicotine is calculated and compared with experimental data.

Using the free volume of van der Waals equation, Carnahan-Starling equation for hard spheres, Wilson equa- tion for nonrandom mixing of solution, NRTL equation and our equation, several new equations of states for pure gases are derived. Using these equations, compressibility factors for pure gases are calculated and compared with Nelson-Obert gen- eralized compressibility factor charts. The equation of states using the concept of molecular nonrandom distribution gave better results than those of molecular random distribution. This shows that the molecular nonrandom distribution makes considerable effect on the equation of states.

의 일차결합에 대한 정규분포로 가정하였다. 난수모의실험을 수행하여 이 가정이 타당하다는 것을 입증하였고, 이 분포로부터 3 성분 논랜덤 혼합 격자용액의 과잉깁스에너지 에 대한 근사식을 유도하였다. 이를 이용하여 여러 3성분용액의 액체-증기 상평형 계산을 하였고 다른 식들의 계산 결과와비교하여 보았다.주제어: 논랜덤 혼합, 삼성분계, 과잉깁스에너지, 격자ABSRTACT. It is assumed for three components lattice solution that the number of ways of arranging particles ran-domly on the lattice follows a normal distribution of a linear combination of N

A new method that optimizes a control of hydrocarbon (HC) addition to diesel exhaust gas for HC type DeNOx catalyst system has been developed. These catalysts are called the HC-DeHOx catalyst in this paper. The system using HC-DeNOx catalyst requires a resonable quantity of hydrocarbons addition in the inlet gas of the catalyst, because the HC concentration in a diesel engine is so low that the HC is not sufficient for NOx conversion. It is expected that this study offers a robust data developing HC injection system.

20 vol.% aluminum borate whisker (Al18B4O33w) reinforced AC4CH alloy composite was fabricated by squeeze casting method. The matrix is controlled its impurities, which make metal alloys, especially AC4CH alloy that is made by restraining 0.2% Iron and aluminum to make a matrix material. The perform of composite materials was made from Al18B4O33w with 5% regulated three kinds of inorganic binders, SiO2, Al2O3 and TiO2 sol, respectively and then sintered at 1373K. The composites were obtained by squeeze cast infiltration of the molten alloy to the perform. Then it was squeeze casting into the matrix. The status of adhesions of whisker perform was Observed by SEM. Micro-Vickers hardness and tensile properties at the room temperature were estimated. Al18B4O33w/ AC4CH composites containing TiO2 sol has excellent properties on tensile properties and microvickers hardness compared with the other composites without inorganic binder, containing SiO2 and Al2O3 sol inorganic binder.

Background/Aims : Continuous renal replacement therapy (CRRT) has been widely used for treating critically ill patients with acute kidney injury (AKI). Whether CRRT is better than intermittent hemodialysis for the treatment of AKI remains controversial. We sought to identify the clinical features that can predict survival for the patients who are treated with CRRT. Methods : We analyzed the data of 125 patients who received CRRT between 2005 and 2007. We identified the demographic variables, the underlying diagnoses, the duration of CRRT, the mean arterial blood pressure (ABP) and the Simplified Acute Physiology Score (SAPS) II. The classification/staging system for acute kidney injury (AKI) was applied to all the patients, who were then divided into stage 1-3 subgroups. Results : The average age of the patients was 61.414.3 years and the mortality rate was 60% (75 of 125 patients). The survivors had a significantly higher mean ABP and a higher mean serum bicarbonate level, which were measured the day after CRRT, than the nonsurvivors (86.723.7 vs. 69.224.6 mm Hg, respectively, 21.43.5 vs. 16.45.4 mmol/L, respectively,; p

It has been shown, using the significant structure theory of liquids, that a lower critical solution temperature behavior as well as a upper critical solution temperature behavior can be expected for polymer–polymer systems and that a phase diagram of closed-loop-type in a polymer–polymer–solvent system can be possible. In this article the sublimation energy of a mixture was expressed as a quadratic form of segment surface fractions on pure components rather than that of mole fractions, and the effect of the segment surface fractions on critical compositions was explained. The calculated partial miscibilities were in good agreement with the experiment.

The significant structure theory of liquids has been applied to the partially miscible systems, of which the temperature-composition phase diagrams are of closed loop type. In this paper, the sublimation energy of a mixture is expressed as a quadratic form of surface area fractions of components, and the energy correction parameter between one component and the other is assumed to be a second order function of temperature for simplicity, although it is a higher order function of temperatures and compositions. The calculated partial miscibilities are in good agreement with the experiment. Considered mixture systems are water-nicotine and waterβ picoline systems.