复合胺砜溶液吸收CO_2传质动力学研究

利用湿壁塔法测量复合胺砜溶液吸收CO_2的动力学特性,实验工况包括不同的反应温度(293.15～323.15 K)和不同的溶液浓度(0.5～6.6 mol/L)。本文简化了气液传质模拟,计算了不同工况下的吸收速率常数、总反应速率常数、二级反应速率常数及增强因子等动力学参数,同时根据实验结果拟合得到了二级反应速率常数和增强因子的经验公式,并得到了复合胺砜溶液与CO_2反应的表观反应活化能为为20.38 kJ/mol。     

Power flow analysis in a hybrid phononic crystal structure

To reveal the energy transmission through a hybrid phononic crystal structure, power flow analysis is carried out in this paper. Hysteretic damping having significant relationship with power flow is added and corresponding theoretical formulas of the dispersion relation are derived. Besides, the power flow in the hybrid structure is calculated by using the finite element method. The results show that as the damping increases, the boundaries of the band gaps become smoother and dimmer, i.e., broader width. With the increase of damping, the power flow is lowered at the resonance frequencies,while slightly increases near the resonance frequencies. The power flow maps manifest energy distribution in the hybrid structure within and out of the band gaps, which can be exploited in the optimization of the structure design.     

金属间化学反应在镀锡层中导致的应力场

镀锡层中锡铜金属间化合物颗粒的生成可以导致内应力的产生,将这种现象视为夹杂的膨胀,采用镜像法求得在有限厚度弹性板内的伽辽金矢量,进而得到弹性板内因夹杂膨胀所产生的应力场,并与有限元软件Abaqus的计算结果进行对比,符合的极好.根据弹性板内应力场的分布,对锡晶须的生成条件及其影响因素进行了预测与分析.结果表明锡晶须生成于自由表面上距离夹杂最近的几何位置.