考虑激光下能级弛豫过程的调QNd：YAG速率方程理论分析

本文比较了考虑与不考虑激光下能级弛豫过程的两种形式的调Q速率方程，并以二极管激光侧面泵浦电光调QNd：YAG为例，分别采用两种形式的调Q速率方程，分析了调Q过程中上、下能级粒子数变化过程，计算了输出调Q激光脉冲波形、峰值功率以及能量，进行了比较分析，并解释了调Q“子脉冲”与拖尾现象。

Precise determination of anomalous scattering factors of Ge by using X-ray resonant scattering

Variations of peak position of the rocking curve in the Bragg case are measured from a Ge thin crystal near the K-absorption edge. The variations are caused by a phase change of the real part of the atomic scattering factor. Based on the measurement, the values of the real part are determined with an accuracy of better than 1%. The values are the most reliable ones among those reported values so far as they are directly determined from the normal atomic scattering factors.

Design and properties analysis of multi-layer dielectric used in pulse compressor gratings

Used in chirped-pulse amplification system and based on multi-layer thin film stack, pulse compressor gratings (PCG) are etched by ion-beam and holographic techniques. Diffraction efficiency and laser-induced damage threshold rely on the structural parameters of gratings. On the other hand, they depend greatly on the design of multi-layer. A theoretic design is given for dielectric multi-layer, which is exposed at 413.1 nm and used at 1053 nm. The influences of coating design on optical characters are described in detail. The analysis shows that a coating stack of H3L (H2L) (boolean AND) 9H0.5L2.01H meets the specifications of PCG well. And there is good agreement of transmission between experimental and the theoretic design. (c) 2005 Elsevier GmbH. All rights reserved.

激光预处理对增透膜阈值的影响

激光预处理是提高光学薄膜激光损伤阈值的有效方法之一。本文就激光预处理前后增透膜损伤阈值的变化、破斑深度的变化、膜层中电场分布情况，分析了激光预处理对阈值的影响及原因。

太行花某些生殖生物学特性的研究

本文通过原产地生境分析、有性生殖和无性生殖调查以及胚胎学研究等，研究了太行花的生殖生物学特性。 太行花分布在太行山东缘，其分布特点为：1、在海拔600-1500米之间，呈间断、零星、条带状分布。 2、主要生长在阴坡裸露崖壁的缝穴中。它的生境条件十分恶劣，气候季节性变化明显，夏季炎热多雨，冬季干燥寒冷;着生太行花的崖缝中只含极少土壤，保水性极差，有机质贫乏，含钙极高。太行花群落植物种类稀少，在调查的三个样地中仅有15个种，分属于9个科、11个属。 生殖途径调查表明：太行花具完整的两性花和单性雄花，两性花能发育成熟最终形成种子，萌发产生新植株，进行有性生殖;由于原产地恶劣的生境条件，有性生殖能力很弱。太行花还通过分蘖茎来进行无性生殖。分蘖茎产生于茎基部，当它出叶成苗并在顶芽基部上产生根后，与母株断开形成新植株。在原产地太行花种群的扩大和繁衍主要依靠无性生殖途径。 通过细胞学的研究，太行花具如下胚胎学特性：花药具有四个小孢子囊;孢原为单列细胞;花药壁由表皮、药室内壁、中层和绒毡层组成，药壁发育为基本型;减数分裂中胞质分裂为同时型;小孢子四分体是四面体;两细胞成熟花粉。胚珠倒生，单珠被，厚珠心;大孢子四分体线状排列;合点端单孢子发育形成8核蓼型胚囊;珠孔端受精;初生胚乳核先于合子分裂，核型胚乳，紫菀型胚;聚合瘦果，成熟时腹缝半裂。在这些特性中瘦果腹缝半裂是蓇葖果演变为瘦果的过渡类型特征。 太行花生殖生物学特性研究证明，虽然太行花正处于濒危状态中，但有性生殖和无性生殖的功能并未丧失，特别是大小孢子的发生和发育、受精和胚胎发生都具有正常的细胞学过程。因此，原产地太行花濒危的原因被认为是由于生殖过程所必需的条件不能满足的结果，也就是说特殊的生境阻碍了有性生殖和无性生殖的过程，从而导致个体数量减少和群体停止扩展。为了防止太行花灭绝，将它迁移到另一个适合于它繁殖的地方去，可能是合理的。