The Phase Transition of Nematic Liquid Crystal Cells Bounded by Surfactant-Laden Interfaces

National Science Foundation of China [50873083, 10974162]Taking into account the surface-coupling strength effect, we discuss the phase transitions of a finite thickness cell bounded by surfactant-laden interfaces in a magnetic field perpendicular to the substrate and it is compared with that of a semi-infinite system. It is found that the larger the thickness, the closer the three-dimensional phase transition surface of the finite system to that of the semi-infinite one. The simulation also shows that when a magnetic field is applied to a nematic semi-infinite sample, an orientational phase transition first takes place close to the interface and then extends to the inner space as the temperature increases

基于OCDMA环形全光网络的自干扰抑制研究

文章提出了一种新的基于环形拓扑结构的光码分多址（OCDMA）接入网络,对网络的模型、性能进行了分析。设计了一种基于周期性频域编码技术的环形网络的自干扰抑制方案,并对该方案进行了分析和讨论。试验证明:该网络允许所有用户同时通信,并且能提高网络的灵活性和效率

Effects of Slope Gradient on Runoff and Sediment Process in Stony Soil by Stimulated Rainfall

对含砾石土壤径流和产沙过程的研究不仅有助于深入理解该类型土壤中的水土过程,也可以为基于过程的土壤侵蚀模型模拟提供重要的土壤参数。通过室内模拟降雨试验,分析了3个坡度下含砾石土壤中的径流和产沙过程,研究结果表明,不同砾石含量的土壤在不同坡度下的产流在0~20 min内有明显增加的趋势,之后径流趋于平稳。随着砾石含量的增加,坡度对径流的影响减弱。坡面产沙高峰期出现在0~20 min内,且高峰期产沙量占总产沙量比例相对较大;当坡度为15°时,砾石含量(质量含量百分比)为20%,30%,40%的土壤在30 min后产沙量又增加,与其他坡度相比,土壤总产沙量也明显增加。实验中坡度是决定土壤产沙量的主要因素