“光”的虚化历程

在汉语的历史长河中,“光”最初为名词,自先秦以来出现动词、形容词的词性,后到近代虚化为限定类范围副词;在语言逐渐演化过程中,其语义和句法结构的使用也产生了一系列用法。通过具体的实例从语义、句法功能及语用分析三方面来论述“光”的语法化历程。     

顺控法编程在交通灯控制中的应用研究

根据十字路口交通灯控制系统的要求,选用西门子CPU224可编程控制器作为十字路口交通灯系统的控制器,应用顺控法编程思想设计出控制系统的顺序功能图,利用顺控继电器指令把顺序功能图转换为梯形图程序,设计出系统的硬件.控制系统硬件结构简单,主要控制功能通过顺控编程方法来实现.具有可靠性高、易于维护和扩展的特点.整个系统在试验台上进行了验证和调试.系统运行良好,满足了控制要求.     

关于反射光偏振态的探讨

讨论反射光偏振的理论依据是麦克斯韦电磁场理论,与介质的折射率、入射光的偏振态及入射角有关,注意相位的改变,然后依据菲涅耳公式来判断.     

Spatial decoupling of light absorption and reaction sites in n-Si photocathodes for solar water splitting

Metal-insulator-semiconductor (MIS) photocathodes offer a simple alternative to p-n junction photocathodes in photoelectrochemical water splitting. However, the parasitic light absorption of catalysts and metal layers in the MIS junction, as well as the lack of low work function metals to form a large band offset with p-Si, severely limit their performance. This paper describes an MIS photocathode fabricated from n-Si, rather than the commonly used p-Si, to spatially decouple light absorption from reaction sites, which enables the majority carriers, instead of the commonly used minority carriers, to drive the surface reaction, making it possible to place the reaction sites far away from the light absorption region. Thus, the catalysts could be moved to the backside of the MIS junction to avoid light shielding. Moreover, the adoption of n-Si unlocks a variety of high work function materials for photovoltage generation. The obtained n-Si MIS photocathode exhibits an applied bias photon-to-current efficiency of 10.26% with a stability up to 300 h.