Discriminating optical parameters in double-layer turbid media by backscattered polarization patterns

In this letter a Monte Carlo(MC) algorithm is used to simulate the propagation of polarized light in double-layer turbid media and the 2-dimentional backscattered Stokes vectors and Mueller matrices are obtained.Relationships between backscattered Mueller matrix and optical properties,such as scattering,absorption and layered structure,are discussed in detail.Integrating the 2-dimentional Mueller matrix elements along radial and azimuthal directions,we obtain a reverse trend with respect to the optical parameters for upper and lower layers,which suggests possibilities for discriminating subtle optical properties in a double-layer structure using backscattered polarization patterns such as Mueller matrix.     

磁布雷顿制冷循环性能的优化分析

基于统计力学的性质推导出了顺磁系统的热力学关系,并构建了以满足居里定律的顺磁材料为工作物质的一般磁布雷顿制冷循环模型。研究了内不可逆性和传热不可逆性对循环优化性能的影响。根据该循环模型,推导出了循环的各种优化关系并深刻讨论了循环的性能特性,所得结果将有助于实际的磁制冷机的优化设计和应用。     

回热式布雷顿制冷循环的性能优化

基于回热式不可逆布雷顿制冷循环模型，导出循环的制冷率、性能系数和输入功率等一些重要性能参数的一般表达式及制冷率和性能系数之间优化关系所满足的方程，研究回热和各种不可逆性对其优化性能的影响，讨论了循环的优化运行区间及其性能界限，确定了最佳传热面积。通过数值计算分析了设计参数对循环的制冷率、性能系数和输入功率的影响。