Thermo-electrically regulated adsorptive sensing method and apparatus

摘要

A thermo-electrically regulated adsorptive sensing device comprising a gas adsorptive sensing element having a stratum of adsorbently sensitive particles, a thermistor for sensing the temperature of the sensing element, a thermo-electric module for controlled cooling and heating of the sensing element, a heat sink, and a controller unit for applying variable amounts of electrical current through the thermo-electric module to appropriately heat or cool the sensing element in a rapid, controlled and accurate fashion. The thermo-electric module may be operated either to maintain the stratum of particles of the sensing element within about 1 DEG (0.6 DEG C.) of the optimal sensing temperature or operated to heat the particles in a controlled fashion to a relatively high purging temperature at which the gas is relatively rapidly desorbed, and then cool the particles in a controlled fashion to a relatively lower sensing temperature at which the gas is relatively rapidly adsorbed by the particles.