“非良导体热导率的测量”的误差分析及改进

“非良导体热导率测量”实验是大学物理实验中很重要的一个实验。实验数据的处理比较繁琐且精确度不高。利用Origin软件处理数据中的非线性拟合和切线功能可以既精确又迅速的得出实验结果,并且结果可视化、数据可及时更新。从而提高了该实验在物理教学中的效果。     

初速度对运动物体在颗粒介质中阻力的影响

采用分子动力学模拟方法研究物体从二维颗粒介质底部上升过程的动力学行为．研究发现，物体在上升过程中所受到的阻力与物体的初速度有关．当物体的初速度较小时，黏性系数随着初速度增加而减小，等效阻力则逐渐增加；而当初速较大时，黏性系数随着初速度增加反而逐渐增加，而等效阻力则逐渐减少，甚至可转变成等效推力．     

Relative energy dissipation-induced effective attraction in granular mixture

This paper presents the investigation of the clustering of the intruders in a vertically vibrated granular bed by means of event-driven simulations.The results indicate that the position of intruders in the vertical direction is not a key factor for their aggregation.Energy dissipation of the intruders and host particles are calculated in the process of intruder-host and host-host collisions.The relative energy dissipation of the intruders to that of the host particles is obtained.We find that clustering of the intruders happens when the relative energy dissipation is negative.The conclusion is verified when the restitution coefficient,density and diameter of the intruders are varied.