The catalytic pyrolyses of rayon have been studied respectively by thermo-gravimetric analysis (TGA) when rayon was treated with phosphoric acid (PA), three ammonium phosphate salts and ammonium sulfate (AS). The air ...The catalytic pyrolyses of rayon have been studied respectively by thermo-gravimetric analysis (TGA) when rayon was treated with phosphoric acid (PA), three ammonium phosphate salts and ammonium sulfate (AS). The air is favorable to the catalysis of dibasic ammonium phosphate (DAP), but not to those of ADP, PA, AP, and AS obviously. It is put forward that a peak’s shape character can be described with the ratio of height to half-height-width (H/W /2) of the peak on a differential thermo-gravimetric (DTG) curve. A flat cracking peak, presenting a more moderate dehydration reaction, has a smaller ratio and could lead to higher carbonization and activation yields. The experimental results prove this view. According to expectation, the order of catalysis is: DAP≥ADP>PA> APAS no catalyst.展开更多
An experimental study is presented for the mixing of one-and dual-line heated jets injected at 60° angle with x-axis into a cold crossflow in a rectangular channel.Measurements of the mean temperature,velocity,an...An experimental study is presented for the mixing of one-and dual-line heated jets injected at 60° angle with x-axis into a cold crossflow in a rectangular channel.Measurements of the mean temperature,velocity,and turbulence intensity together with the flow visualization were performed.Self-similar forms for the dimensionless vertical temperature profiles were found.Parametric variations characterizing the mixing processes of the temperature and velocity fields were examined and correlated in terms of the momentum flux ratio and downstream distance.Results show that both the thermal and velocity penetration depths increase with increasing momentum flux ratio and downstream distance.The turbulence intensity is strong within the region of jet half-width,and the maximum value occurs at a point close to the jet velocity trajectory.展开更多
文摘The catalytic pyrolyses of rayon have been studied respectively by thermo-gravimetric analysis (TGA) when rayon was treated with phosphoric acid (PA), three ammonium phosphate salts and ammonium sulfate (AS). The air is favorable to the catalysis of dibasic ammonium phosphate (DAP), but not to those of ADP, PA, AP, and AS obviously. It is put forward that a peak’s shape character can be described with the ratio of height to half-height-width (H/W /2) of the peak on a differential thermo-gravimetric (DTG) curve. A flat cracking peak, presenting a more moderate dehydration reaction, has a smaller ratio and could lead to higher carbonization and activation yields. The experimental results prove this view. According to expectation, the order of catalysis is: DAP≥ADP>PA> APAS no catalyst.
基金Partial support of this work by the Science and Technology Coordination Council in Defence in Taiwan under Grants CS 79-0210-D110-03
文摘An experimental study is presented for the mixing of one-and dual-line heated jets injected at 60° angle with x-axis into a cold crossflow in a rectangular channel.Measurements of the mean temperature,velocity,and turbulence intensity together with the flow visualization were performed.Self-similar forms for the dimensionless vertical temperature profiles were found.Parametric variations characterizing the mixing processes of the temperature and velocity fields were examined and correlated in terms of the momentum flux ratio and downstream distance.Results show that both the thermal and velocity penetration depths increase with increasing momentum flux ratio and downstream distance.The turbulence intensity is strong within the region of jet half-width,and the maximum value occurs at a point close to the jet velocity trajectory.
