三倍折反式电视跟踪变焦距物镜的设计

<正> 一、引言根据高斯光学,物象垂轴放大率为:β=(y′/y)=-(f/x)=-(x′/f′)此式表明,某一确定距离上的固定大小目标,通过定焦系统所成象的大小是一定的。随着距离的改变,象的大小也相应地改变。如果要求象的大小不随距离x的变化而变化,则必须使焦距f作相应的变化,即应用变焦距系统。     

Low Resistivity C54 Phase TiSi2 Films Synthesized by a Novel Two—Step Method

Synthesis and growth properties of the TiSi2 film on a Si (001) substrate are investigated. A novel two-step method is used for deposition of the C54 phase TiSi2 film with low resistivity. The first step is the formation ofthe C49 phase TiSi2 at a relative low substrate temperature of 400℃, followed by rapid thermal annealing processat 850℃ in N2 for the formation of the C54 phase TiSi2 as the second step. Finally, selective wet, etching isemployed to remove the un-reaction Ti on the surface and the low resistivity C54 TiSi2 film can be obtained. Thefilms deposited under various parameters are evaluated by scanning electron microscopy, x-ray diffraction and the resistivity measurement. Compared with other sputtering technologies used commonly for TiSi2 synthesis,this two-step method has apparent advantages such as the mild synthesis temperature and the high purity of the final product with low resistivity, uniform large area and improving surface roughness. In addition, the film also shows that the low coefficient of resistivity-temperature appears in the temperature range from 20℃to 800℃.     

Symmetries and Strong Symmetries of the （3＋1）-Dimensional Burgers Equatio

The strong symmetries (recursion operators) and the inverse strong symmetries of a (3 1)-dimensional Burgers equation are given explicitly.Infinitely many symmetries of the considered model are obtained by acting the strong symmetries and the inverse strong symmetries on some seeds.An infinite-dimensional full Lie point symmetry algebra is also given.     

自润滑轴承失效原因的XPS分析

用Ｘ射线光电子能谱仪（ＸＰＳ）对失效前后的自润滑轴承各部件表面的化学组成及其状态进行了分析，结果表明失效前后表面性质差异较大，失效是由于自润滑膜破损耗尽所致。     

粪箕笃中两个新颖的含硝基莲花氏烷型生物碱

Two unusual nitro-substituted hasubanan-type alkaloids, stephalonines J （1） and K （2）, together with ten known alkaloids, protostephanine, dehydrostephanine, （-）-stephanine, （-）-isolaureline, R-roemeroline, （＋）-pronuciferine, （ ＋）-stephafine, （ ＋ ）-N-acetylstephafine, （ ＋ ）-lirioferine, and （ ＋ ）-norlirioferine, were isolated from the whole plant of Stephania longa. Their structures were characterized mainly by spectroscopic methods including IR, MS, and NMR experiments, and the structures of 1 and 2 were further confirmed through chemical correlations with the known alkaloids stephalonines A （1a） and B （2a）, respectively.     

三氯异氰尿酸作为氯源实现α-氰基酮和1,3-二羰基类化合物的氯化

报道了以三氯异氰尿酸作为氯源,在室温条件下高效实现了α-氰基酮类化合物和1,3-二羰基类化合物氯化反应的研究.该反应过程条件温和,无需额外添加氧化剂或碱.     

葡萄糖、肌醇与抗坏血酸的相互作用研究

利用电化学、密度泛函理论和分子中的原子理论,从微观角度研究了葡萄糖、肌醇与抗坏血酸的相互作用。两种混合体系在水溶液及磷酸盐缓冲溶液中的电化学结果表明,抗坏血酸中烯二醇羟基上的氢原子可与葡萄糖/肌醇羟基上的氧原子形成氢键,使得抗坏血酸的电氧化反应难以发生。量子化学计算进一步证明了上述两种混合体系中氢键的存在。     

由4',4''-二羟基-2-甲酸－三苯基甲烷及其衍生物制备高碳超支化芳香聚酯

合成了一系列含羟基和乙酰氧基的超支化聚酯,将4',4'二羟基-2-甲酸－三 苯基甲烷（酚酞啉）直接缩聚和将4~＇,4~＂-二羟基-2-甲酸－三苯基甲烷进行酯 交换反应都成功得到了超支化聚酯,以PS作标准物,由GPC测得的重均分子量为 2000到8000,~13C NMR测试表明聚合物支化度略高于50%,聚酯的玻璃化转变温度 依赖于末端和侧基官能团类型,该超支化聚酯末端含有反应性官能团,具有类似线 性高分子的高的热稳定性,相比之下,由于其大分子的形状和官能团的影响,末端 为乙酰氧基的超支化聚枉费显示了优良的溶解性能,这与一般线性高分子大不相同 ,由于氢键的存在,末端为羟基的超支化聚酯的溶解性能不佳,但是酸酯显示了 优良的溶解性能,这与一般线性高分子大不相同,由于氢键的存在,末端为羟基的 超支化聚枉费的溶解性能不佳,但是酸化可破坏氢键网络,得到的超支化聚酯可深 于一般有机溶剂。     

AMT在铜表面形成保护膜的STM研究

5一氨基七一流基一1、3、各喀二隆（AMT不仅是一种有效的感光材料和分析试剂，同时作为重要的中间体被广泛应用于农药、医药生产中间，但作为铜腐蚀抑制剂的应用还远不如苯并三氯哩．实验表明［'－'l，AMT在酸性、中性及碱性介质中对铜及其合金均具有较好的缓蚀作用，经AMT处理     

高血压患者血清中铁锌铜锰硒铬含量的研究

１６５例高血压患者血清中铁，锌，铜，锰，硒，铬的含量与对照组比较，结果显示：１．微量元素铁，锌含量明显升高，而血清铜，铬含量明显降低，其差异均有高度显著性，Ｐ〈０．０１；血清锰和硒的含量，两者差异无显著性，Ｐ〉０．０１．２．上述元素含量的特点可用高血压病的早期预报和治疗。