A blower with the improved P-Q characteristics is provided. The NOx trap composition is produced by heating an iron-containing zeolite in the presence of an inert gas and an organic compound to produce a reductively calcined ironzeolite. When the pressure in the main fluid supply channel rises above the no-load operating start pressure and reaches a no-load operation pressure, the auxiliary fluid supply channel is cut off from the main fluid supply channel. The quantization and coding of the wavelet coefficients are related to the curves. The operational amplifier has its slew rate improved without detracting from stability against oscillation and continuity of the output waveform.