Thermal vaporization sources conductive

Room-temperature ionic liquids are attractive due to their chemical and thermal stability, negligible vapor pressure, high ionic conductivity, and ample electrochemical window. Their properties can be varied by a rational choice of the cations and of the anions and can represent an important iodide source for an I /I3 -based electrolyte (Fig. 17.12). 

Instantaneous vaporization requires that the latent heat be very rapidly supplied to the sample after injection (e.g., water requires 0.5 cal/mg). This heat must be supplied by the carrier gas or the material of the injector. The carrier gas is a very poor source. The heat must, therefore, come from the material of the injector usually having a poor thermal conductivity. Thus, the temperature of the injector must be very high or a large hot surface area must be available. Unfortunately, the consequences of high temperatures to heat-labile compounds are disastrous. 

For a discussion of the uncertainties associated with the equation of state and thermal conductivity entries of this table, please see the source references given above. The uncertainty in viscosity is 1% in the liquid below 474 K, 2% in the liquid at higher temperatures and in the vapor, and 5% between 623 and 723 K at pressures between 16 and 50 MPa. The uncertainty in viscosity is 2% in the liquid below 623 K and in the vapor below 573 K, 5% elsewhere in the liquid and vapor, and 10% in the critical region (623 to 723 K and 21.66 to 50 MPa). 

The values in these tables were generated from the NIST REFPROP software (Lemmon, E. W., McLinden, M. O., and Huber, M. L., NIST Standard Reference Database 23 Reference Fluid Thermodynamic and Transport Properties—REFPROP, National Institute of Standards and Technolo, Standard Reference Data Program, Gaithersburg, Md., 2002, Version 7.1). The primary source for the thermodynamic properties is Magee, J. W., Outcalt, S. L., and Ely, J. F., Molar Heat Capacity C(u), Vapor Pressure, and (p, Rho, T) Measurements from 92 to 350 K at Pressures to 35 MPa and a New Equation of State for ChlorotrifluorometEiane (R13), Int. J. Thermophys. 21(5) 1097-1121, 2000. Validated equations for the viscosity and thermal conductivity are not currently available for this fluid. 

Ionization detectors measure variations in saturation current of a gas passing between two electrodes across which a constant voltage is applied. The variation in current is caused by ionized, organic vapors as they emerge from the column, and is amplified and recorded as with the thermal-conductivity detector. The organic vapors are ionized either by a source of... 

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