Gas solubility coefficients

Potency is described by the minimum alveolar concentration (MAC) of an agent and lipid solubility by the oil gas solubility coefficient. 

Xenon 131 kDa boiling point —108 °C blood gas solubility coefficient 14 oibgas solubility coefficient 1.9 MAC 71 odourless. 

It is a isomer of enflurane and its chemical and physical properties are similar to enflurane, but it is approximately Vi times more potent, more volatile. It has a lower blood gas solubility coefficient than enflurane. It produces rapid induction and recovery. 

Sevoflurane is a fluorinated methyl isopropyl ether (Figure 3.2). It was first released for clinical use in Japan in 1990 and it is now available in many other countries worldwide. Being relatively insoluble (blood/gas solubility coefficient, 0.68) it has the potential to provide rapid anaesthetic induction and recovery. Unlike isoflurane it is non-irritant to the airway and can be given in high concentrations for anaesthetic induction. Its MAC ranges from 3.3 in infants to 2.5 in older children and 1.8 in adults. 

Practically, more commonly used are other convenient parameters of balanced distribution for nonpolar components in interacting media. These are solubility coefficients. Solubility coefficients (gas-solubility coefficients) describe the bond between partial pressure of component i and its concentration in aqueous solvent, i.e., in systems CH -H O, C Hg-H O, CgHjgO-H O, etc. Appearance of these coefficients is associated with a law discovered by British chemist William Henry (1775-1836) in 1803. He... 

Much more rarely is used Kuenen gas-solubility coefficient, which describes volume of component i solved in unit weight of water at partial pressiue 1 bar. Even rarer is encoimtered Ostvald solubility coefficient, which describes the ratio of component i concentrations in water and gas phase in conditions of equilibriimi at low pressure. This nondimensional coefficient in its content is similar to the partition coefficient expressed not in molar fractions and this is why it is not equal to it. 

Compounds f E S 1 Q Free enthalpy, AZJj, Saturation vapor pressure Solubility Henry gas-solubility coefficient ... 

Using the solution-diffusion model, the gas permeability coefficient can also be written as the product of a gas solubility coefficient, Sa, and a concentration-averaged, effective diffusion coefficient. Da [167] ... 

Similar relationships apply for the description of the permeation of gases through geomembranes. However, some differences in quantities and imits used must be pointed out. A detailed analysis is presented in (Piringer 1993). The gas is not characterised by a concentration, but by its partial pressure p. Eq. 7.7 then is replaced by Henry s law, according to which concentration Ci of gas molecules dissolved in the geomembrane is proportional to the partial pressure of the gas outside the geomembrane. The proportionality factor is mainly called Henry s constant or gas solubility coefficient S ... 

A similar order was observed in the storage modulus and CED. Gas solubility coefficients of the five polyimide films were essentially independent of polymer structure and similar to those of the polyimide films in our previous study(8). 

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