Preparation and photochromic properties of NiAl-NO3- LDHs/LDPE composite

Nanoscale NiAl-NO3-LDHs with good crystallinity have been synthesized by a method, Separate Nucleation and Aging Steps (SNAS). An NiAl-NO3-LDHs/LDPE composite was prepared by blending NiAl-NO3-LDHs and LDPE in a heated double-roller mixer. The color of this composite changed from olive green to steel gray under UV irradiation. After heating at 80oC for 2 h, the color returned to olive green. The effect of varying the amount of added NiAl-NO3-LDHs and UV exposure time on the photochromic properties of the composite has been investigated. The results showed that the photochromic phenomenon becomes more apparent with increasing amount of NiAl-NO3-LDHs. When the amount reaches 5%, the composite exhibits good photochromic properties and reproducibility. The color change rate of the composite reaches a maximum when the irradiation time exceeds 20 min. The addition of LDPE improves the photochromic cyclability of NiAl-NO3-LDHs significantly. The addition of nanoscale NiAl-NO3-LDHs also improves the mechanical properties of LDPE to some extent.     

粒子对光的多级散射——辐射传播和相干背散射

此书对在少数随意粒子构成的介质中光和其它电磁辐射的多级散射进行了新的严谨的处理。书中将辐射传播理论（RTT）作为经典宏观电磁学的一个分支进行了全面介绍；用RTT系统分层次地讨论了不同粒子群介质中的电磁散射和相干背散射（CB）效应；用专门的章节严谨地讨论了辐射传播方程（RTE）的物理内涵和应用范围；比较了辐射传播的自洽微观物理和传统的唯象近似；讨论了解辐射传播方程的先进方法；并给出了在没有入侵粒子情况下，RTT和CB的应用实例及其物理基础、特征和遥感。     

高产水稻剑叶的叶绿素含量、捕光色素分子的内禀特性与饱和光强关系的研究

叶绿素是水稻叶片进行光合作用的重要物质之一。为了研究叶片叶绿素的含量、捕光色素分子的内禀特性与饱和光强的关系,利用LI-6400XT便携式光合测定系统测量了6个水稻品种的光响应曲线,并利用光合作用对光响应的机理模型进行了拟合。结果表明:供试的6种水稻品种的饱和光强只与植物捕光色素分子的物理参数如本征光能吸收截面、激子传递到光反应中心的速率(kp)、热耗散速率(kD)和激发态的平均寿命(?)等有关,与叶片的叶绿素含量无关。