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A study was made of the effect of the frequency and intensity of the gas oscillations on mass transfer between a gas and a solid surface, under conditions of a linear oscillation direction and a precisely defined surface shape, for the purpose of obtaining the transport mechanism. For the reaction model, the hydrogenation of C2H4 on Pd catalyst was selected. The reaction was 1st-order. Based on the exptl. conditions, the hydrogenation rate depends only on the C2H4 transport to the catalytic tube wall. The reaction mixt. had the following compn.: C2H4 1, H2 4, O2 0.4, and N2 94.6%; the reaction temp. was 184 Deg, the catalytic zone length 23 cm, the gas velocity 15-60 cm/sec, the permanence time 0.4-1.5 sec and oscillation frequencies 275, 400, 425, 530, 630, 730, 875, 920 and 1325 Hz, the oscillation intensity was ?175 decibels. The reaction rate const. increases with the oscillation pressure from a detd. frequency-depended value and this effect increases at low frequencies. The mass-transfer coeffs. were obtained from the rate consts. A study was made of the variation of these coeffs. with the gas rate, for different oscillation pressures, Reynolds nos., and variation of oscillations. [on SciFinder (R)]