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The triple point temperature of refrigerants is crucial because it serves as a reference for the lower limit of their use temperature in a refrigeration system. In this study, the triple point temperatures for recently proposed refrigerants with low global warming potential were experimentally determined. Ten hydro-fluoro-olefins, two hydro-chloro-fluoro-olefins, and trifluoroiodomethane were investigated. The triple point temperatures of the refrigerants were determined from the obtained cooling and heating curves. To improve measurement accuracy, measurements were conducted on samples obtained from different companies using two different measurement devices. The measured data were found to be in good agreement within the estimated measurement uncertainty., International Journal of Refrigeration, 133, pp.172-180; 2022

The triple point temperature of refrigerants is crucial because it serves as a reference for the lower limit of their use temperature in a refrigeration system. In this study, the triple point temperatures for recently proposed refrigerants with low global warming potential were experimentally determined. Ten hydro-fluoro-olefins, two hydro-chloro-fluoro-olefins, and trifluoroiodomethane were investigated. The triple point temperatures of the refrigerants were determined from the obtained cooling and heating curves. To improve measurement accuracy, measurements were conducted on samples obtained from different companies using two different measurement devices. The measured data were found to be in good agreement within the estimated measurement uncertainty., International Journal of Refrigeration, 133, pp.172-180; 2022

In the work of Den Ouden the level-set method has been used to model the growth and dissolution in a steel alloy of the precipitate cementite and the diffusive phase austenite. The movement of the interface between the two phases is controlled by the diffusion of carbon and a reaction on the interface between the two phases. In this thesis research a similar model and method is given for a three-phased model with an extra diffusive phase. This third phase is ferrite, which nucleates on the interface of austenite and cementite when the temperature is dropped below the eutectoid temperature for a high carbon steel alloy. The difference between austenite and ferrite is the matrix structure of the iron atoms. This influences how much carbon the phase can contain. The difference in structure also results in different properties of the steel with respect to strength, hardness, etc. Modeling the growth of this three-phased steel alloy could eventually lead to useful insights for high-carbon steel production.\\ Extra difficulties arise by the introduction of a second diffusive phase. These difficulties concern defining sufficient interface boundary conditions between the different phases, capturing the different phases with the level-set method, creating a qualitative good mesh capturing these phases, recovering gradients on an interface and getting correct carbon concentration value in the triple points because of the interface boundary conditions. Except for the latter problem, the results of this research show decent results. The effect of cooling on the growth of ferrite is also shown and explained.

In the work of Den Ouden the level-set method has been used to model the growth and dissolution in a steel alloy of the precipitate cementite and the diffusive phase austenite. The movement of the interface between the two phases is controlled by the diffusion of carbon and a reaction on the interface between the two phases. In this thesis research a similar model and method is given for a three-phased model with an extra diffusive phase. This third phase is ferrite, which nucleates on the interface of austenite and cementite when the temperature is dropped below the eutectoid temperature for a high carbon steel alloy. The difference between austenite and ferrite is the matrix structure of the iron atoms. This influences how much carbon the phase can contain. The difference in structure also results in different properties of the steel with respect to strength, hardness, etc. Modeling the growth of this three-phased steel alloy could eventually lead to useful insights for high-carbon steel production.\\ Extra difficulties arise by the introduction of a second diffusive phase. These difficulties concern defining sufficient interface boundary conditions between the different phases, capturing the different phases with the level-set method, creating a qualitative good mesh capturing these phases, recovering gradients on an interface and getting correct carbon concentration value in the triple points because of the interface boundary conditions. Except for the latter problem, the results of this research show decent results. The effect of cooling on the growth of ferrite is also shown and explained.

In the present work, we have examined the influence of surface shell exchange coupling on the magnetic properties of a diluted ferromagnetic spin- 1 Ising nanocubic particle, by employing the effective-field theory with correlations based on the probability distribution technique. Some interesting results have been found such as, a tricritical point, a triple point, an isolated critical point, reentrant and even double reentrant phenomena, S-, R- and Q-type behaviors, as well as, both first-and second-order phase transitions as it is confirmed by the free energy. In addition, when the interactions are low between the surface shell sites, quadruple hysteresis loops can be seen in the system.

When the pressure of a liquid drops below its triple point, a phase transformation occurs forming both solid and gas phases with no remaining liquid. Liquid cryogens vented from launch vehicles, such as the Centaur Upper Stage, will undergo such a transformation when exposed to pressures below their triple points. Solids thus formed may accumulate in the overboard vent, restricting flow and possibly blocking the vent. An investigation of vent blockage was performed using saturated liquid argon. Observations of solid adherence and accumulation were recorded for various argon delivery pressures. Wall adherence and vent blockage was strongly dependent on delivery pressure, with accumulation increasing for decreasing pressure. For low delivery pressures, relative to the triple point, vent blockage was immediate and complete. In addition, solid formation was observed to propagate into the liquid, against the direction of flow, revealing the porous nature of the solid as well as the impact on the flow.

We evaluate the Bell-lattice-model for water by exploring the parameter space by means of the Cluster Variation method of Kihuchi. We use ten order parameters to describe the different occupation of tetrahedrons in the lattice, with and without hydrogen bonds. The phase diagrams are represented in the density-temperature plane and in the pressure temperature plane. An explanation is given as to why there are first order terminal points in the metastable region. We discuss the 180 degree rule and display the ratios of hydrogen bonded pairs versus non-hydrogen bonded pairs. (Author)

A technique was developed for measuring the melting temperatures of graphite, and the graphite-liquid-vapor triple point by means of continuous HF laser in the pressure range 120 to 215 atm. The triple point was found to be 120 + or - 10 atm and 4130 + or - 30 K for pyrolytic graphite. The results with neon, argon, and krypton as pressurization gases were concordant. A vapor-solid- liquid phase diagram was obtained in the vicinity of triple point. Photomicrography, electron micrography, x-ray diffraction, and ion microprobe mass analysis were used to characterize the structure of frozen liquid droplets, the pyrolytic graphite matrix, and condensed vapor.

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