吡喃鎓盐新激光染料的研究

合成了一系列吡喃鎓盐激光染料(P_1～P_8)。对它们的激光性能研究表明:新激光染料调谐范围为66～76nm,显著大于荧光素钠的文献值(29nm),与常用的优良激光染料罗丹明6G相比,激光能量转化率较接近,但调谐范围略宽,且光化学稳定性也很好。新激光染料(P_6)和香豆素4相混合后的混合染料,能够产生能量传递激光,且输出能量转化率(16.3%)高于单一染料(香豆素为12%,P_6为6.9%)。染料的Stokes位移与溶剂的参数之间满足Lippert方程,染料基态时的偶极矩小于激发态的偶极矩。所以新激光染料可用作绿光区激光染料。     

单模连续1.32μmNd~(3+):YAG激光器

本文给出了1.32μm单模连续Nd~(3+):YAG激光器的研制和实验结果。激光器采用修改工作物质端面以补偿热效应,选取不对称腔长来增加基模体积,设计了高选择性的腔镜膜层,抑制1.06μm振荡,获得了单模连续输出。     

Nd~(3+):YAG激光器提高输出和谱线调谐运转的实验研究

激光棒的热效应是影响固体激光器提高输出的重要因素。本文采取热补偿方式,首先测定其热焦距,确定补偿曲率,给出工艺方法,最后得到显著提高的输出,并选用实心F-P标准具和它们的组合调谐出荧光带中弱线的连续运转。     

关于填补构造——以马角坝地区多级序不协调叠瓦式构造为例

本文根据四川江油马角坝地区大量实例提出的填补构造,是指充填岩层虚脱空间补偿那里压应力不足的层间构造。填补有多种形式。其中,填补褶皱是区别于寄生褶皱的另一类从属褶皱,填补角砾岩是构造角砾岩之一。马角坝地区三个级序的不协调构造中,Ⅱ,Ⅲ级分别是高一级序构造的填补构造,Ⅰ,Ⅱ级为叠瓦式构造,Ⅰ级构造组成的叠瓦式构造是一个大型推覆体上盘系统中的无根薄皮构造。     

气刀操作条件对密相栓流气力输送的影响

以高密度聚乙烯为对象,进行了密相栓流气力输送的中试研究,结果表明:输送压力、气刀的操作周期、充气时间与断气时间的比值对输送气速、输送能力、固气比等均有较大的影响.     

^4He^＋离子在C和Cu上能量沉积系数的理论计算

利用部分地考虑能量损失的角关联的改进离子输运双群模型，计算了＾４Ｈｅ＾＋离子垂直入射到Ｃ和Ｃｕ上的能量沉积参数，改进了早期的离子输运双群模型。     

徐州红色鲢鱼的初步研究

对红色鲢鱼和白色鲢鱼进行比较研究,结果表明,除体色差别外,两者在体形、咽骨咽齿、消化管相对长度、鳍式和鳞式等方面均无显著差异。可以认为红鲢是白鲢的红色变异体,并对色变的原因做了些推测。     

高阶非线性非完整系统的相对论性广义Boltzmann—Hamel方程

本文由万有D'Alembert原理推导出高阶非线性非完整系统的相对论性广义Boltzmann-Hamcl方程。     

铁路沿线山岬对电波传播特性影响分析

利用波导分析理论及介质表面阻抗的概念,分析了电波在非理想表面的山岬中的传播特性．同时,对频率为９００ ＭＨｚ 的电波在非理想表面的矩形山岬内的传播特性进行了理论计算与分析．计算分析结果表明,环境媒质的相对介电常数对电波传播特性的影响较其它环境参数对电波传播特性的影响要明显得多．非理想表面介质增加了电波传播能量的损耗,缩短了纵向传播距离．在传播的横截面上,水平方向的电场衰减呈现波动分布．     

Perceiving distance accurately by a directional process of integrating ground information

By itself, the absolute distance of an object cannot be accurately judged beyond 2-3 m (refs 1-3). Yet, when it is viewed with reference to a flat terrain, humans accurately judge the absolute distance of the object up to 20 m, an ability that is important for various actions. Here we provide evidence that this is accomplished by integrating local patches of ground information into a global surface reference frame. We first show that restricting an observer's visual field of view to the local ground area around the target leads to distance underestimation, indicating that a relatively wide expanse of the ground surface is required for accurate distance judgement. Second, as proof of surface integration, we show that even with the restricted view, the observer can accurately judge absolute distance by scanning local patches of the ground surface, bit by bit, from near to far, but not in the reverse direction. This finding also reveals that the surface integration process uses the near-ground-surface information as a foundation for surface representation, and extrapolation to the far ground surface around the target for accurate absolute distance computation.