Argon physical constants

Colloidal potassium has recently been proved as a more active reducer than the metal that has been conventionally powdered by shaking it in hot octane (Luche et al. 1984, Chou and You 1987, Wang et al. 1994). To prepare colloidal potassium, a piece of this metal in dry toluene or xylene under an argon atmosphere is submitted to ultrasonic irradiation at ca. 10°C. A silvery blue color rapidly develops, and in a few minutes the metal disappears. A common cleaning bath (e.g., Sono-clean, 35 kHz) filled with water and crushed ice can be used. A very fine suspension of potassium is thus obtained, which settles very slowly on standing. The same method did not work in THF (Luche et al. 1984). Ultrasonic waves interact with the metal by their cavitational effects. These effects are closely related to the physical constants of the medium, such as vapor pressure, viscosity, and surface tension (Sehgal et al. 1982). All of these factors have to be taken into account when one chooses a metal to be ultrasonically dispersed in a given solvent. 

II is a function of hydrodynamic parameters of the model. Unfortunately, these parameters which describe the effect of hydrodynamics do not correspond to any physical quantity nor can they be Independently evaluated. For some models, the value of w is a constant. For example, the penetration and surface renewal models (Danckwerts, 31) predict w 0.5, while for the boundary layer model w 2/3. The film-penetration model, on the other hand, predicts that w varies between 0.5 and 1 (Toor and Marchello, 32). Knowledge of the effect of dlffuslvlty on k Is needed in evaluating the various mass transfer models. Calderbank (13) reported a value of 0.5 Linek et al. (22) used oxygen, Helium and argon. The reported diffusion coefficients for helium and similar gases vary widely. Since in the present work three different temperatures have been used, the value of w can be determined much more accurately. Figure 4... 

Properties. — The constants for the chief physical properties of argon are given in Table VII, page 21. 

In the Huang and Radosz version of SAFT [71, 72] the Chen-Kreglewski dispersion term is used. This term is obtained from a fit to the physical property data of argon and is given by Eq. (89) [76], where t is a constant equal to 0.74048. The constants Dij are given by Chen and Kreglewski [76]. 

The calculations of the temperature profiles within the cavern walls tank into account the physical properties of the rock surrounding the cavern. The CDF simulations require a fixed thickness for the cavern wall layer. In the present simulation, this thickness is taken equal to 6 m. Outside this layer the rock temperature is constant and equal to the bulk temperature of the cavern rock. The bulk rock temperature is equal to the temperature of the air occupying the cavern when the accident occurred and the argon was released (i.e. at t = 0). The initial conditions in the cavern before the release are 295 K and 1250 mbara. 

Hattig, C., Christiansen, O., 8c Jorgensen, P. (1998b). Coupled cluster response calculations of two-photon transition probability rate constants for helium, neon and argon. Journal of Chemical Physics, 108, 8355. 

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