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热场发射扫描电镜中的复合物镜和镜筒内探测系统
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作者 高尚 马清 +3 位作者 孙千 黄梦诗 陈双文 张青 《测试技术学报》 2023年第5期400-407,共8页
为了解释镜筒内探测器对信号发射角衬度反映的依赖,借助光镜像差类比方法解释物镜和探测系统协调工作以探测信号的原理,最后分析了两种当前使用复合物镜的探测系统。以上研究表明,在当代热场发射扫描电镜中,借助物镜的磁场和电场,物镜... 为了解释镜筒内探测器对信号发射角衬度反映的依赖,借助光镜像差类比方法解释物镜和探测系统协调工作以探测信号的原理,最后分析了两种当前使用复合物镜的探测系统。以上研究表明,在当代热场发射扫描电镜中,借助物镜的磁场和电场,物镜和探测系统协同能够实现筛分和过滤信号的目的,使用光镜类比可以成功地理解各种镜筒内探测器对信号的接收情况。 展开更多
关键词 场发射扫描电镜 低加速电压 复合物镜 镜筒内探测器
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扫描电子束曝光机复合物镜的研究与设计
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作者 夏善红 朱协卿 《电子科学学刊》 CSCD 1991年第2期183-192,共10页
在综合研究已有的各种复合物镜(如移动物镜、变轴物镜和摆动物镜等)的基础上,本文对复合物镜的一般理论进行了探讨,推导了普遍化计算公式,并提出新的复合物镜(弯曲物镜)系统。采用解析函数近似表示系统场分布,对弯曲物镜系统象差进行了... 在综合研究已有的各种复合物镜(如移动物镜、变轴物镜和摆动物镜等)的基础上,本文对复合物镜的一般理论进行了探讨,推导了普遍化计算公式,并提出新的复合物镜(弯曲物镜)系统。采用解析函数近似表示系统场分布,对弯曲物镜系统象差进行了理论分析,并设计出一个实际系统。数值计算结果给出该系统在5×5mm^2扫描场内,束孔径角5mrad和能散2.5eV下,最大彗差0.005μm,横向色差0.001μm。 展开更多
关键词 电子束曝光机 复合物镜 电子光学
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多重复合抛物镜(M—CPC)的概念,意义,优点和设计原则 被引量:1
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作者 剑乔力 《新能源》 1998年第6期1-7,共7页
本文描述了太阳技术面临的深刻技术性矛盾以及复合抛物镜自身固有的限制,在此基础上提出多级复合抛物镜的概念,意义,优点和设计原则。
关键词 多重复合物镜 太阳能 聚光器 供热系统 集热器
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高效率侧面泵浦Nd:YAG激光器 被引量:1
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作者 李含 谷开慧 +1 位作者 齐晓宇 赵帅 《激光与红外》 CAS CSCD 北大核心 2018年第11期1363-1367,共5页
太阳能是地球上资源最为丰富的一种能源,但是其能量密度较低,不足以实现泵浦激光器的需求。为了实现利用太阳能泵浦激光器的目的,需要对太阳光进行高效聚焦,来达到泵浦激光器能量阈值的要求。我们采用三维复合抛物镜(3D-CPC)与菲涅尔透... 太阳能是地球上资源最为丰富的一种能源,但是其能量密度较低,不足以实现泵浦激光器的需求。为了实现利用太阳能泵浦激光器的目的,需要对太阳光进行高效聚焦,来达到泵浦激光器能量阈值的要求。我们采用三维复合抛物镜(3D-CPC)与菲涅尔透镜相结合的聚光系统来实现太阳光的高效聚焦,实验中将3D-CPC聚光系统的出口放置在激光器椭圆柱形泵浦腔的一个焦点处,聚焦后太阳光高效耦合进入激光器谐振腔,实现了聚光比的大幅度提升。利用此聚光系统与椭圆柱形泵浦腔的结合,泵浦Nd:YAG晶体,得到6.2W的激光功率输出,光收集效率达到6. 2 W/m^2。 展开更多
关键词 太阳能 激光器 菲涅尔透镜 ND:YAG 复合物镜聚光器
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Preparation of Novel Composite from Natural Rubber, Bagasse and Plaster 被引量:1
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作者 Sa-Ad Riyajan Isara Intharit +1 位作者 Suthikiat Thaiprasansup Pramuan Tangboriboonrat 《Journal of Chemistry and Chemical Engineering》 2010年第8期56-62,共7页
The sugar cane bagasse was treated with chemical treatment including sodium hydroxide and silane. The characterization of the modified bagasse was achieved with Fourier transform infrared spectroscopy (FTIR), and sc... The sugar cane bagasse was treated with chemical treatment including sodium hydroxide and silane. The characterization of the modified bagasse was achieved with Fourier transform infrared spectroscopy (FTIR), and scaning electron microscopy (SEM). Results showed that the presence Si-CH3 group occurred on bagasse surface after chemical modification. In addition, the roughness of the modified bagasse was higher than that of unmodified bagasse due to chemical modification from sodium hydroxide. Two polymer composite types, namely (1) natural rubber NR/sugar cane bagasse and (2) NR/plaster via two-roll mill method, were prepared. The optimum cure (t90) and torque of the NR/plaster increased with increasing plaster loading in composite. In case of NR/bagasse, the tgo of this sample decreased as a function of sugar cane bagasse while torque of this sample increased with increasing sugar cane bagasse. The modulus of the resulting composite increased with increasing both plaster and sugar cane bagasse, but the tensile strength and elongation at break of the composite decreased as a function of both piaster and sugar cane bagasse in composite. 展开更多
关键词 Natural rubber COMPOSITE BAGASSE PLASTER chemical modification.
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Preparation of nanosized composite photocatalyst ZnO-SnO2 by fractional homogeneous precipitation
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作者 ZHANG Mao-lin LI Long-feng +3 位作者 AN Tai-cheng WANG Xin-ming SHENG Guo-ying FU Jia-mo 《Journal of Chemistry and Chemical Engineering》 2008年第6期14-17,共4页
The nanosized binary mixed oxides of Zn/Sn had been prepared by the fractional homogeneous precipitation route using urea as the latent precipitant under boiling reflux condition The samples prepared with the differen... The nanosized binary mixed oxides of Zn/Sn had been prepared by the fractional homogeneous precipitation route using urea as the latent precipitant under boiling reflux condition The samples prepared with the different initial concentrations of urea or calcined at different temperatures had been investigated by X-ray diffration (XRD) or transmission electron microscopy (TEM). The calcination temperature had obvious effect on the phase composition and the crystal size of the samples attained, and the precipitant concentration also had obvious effect on the oxide particles size and the production rate of ZnO. 展开更多
关键词 PHOTOCATALYST ZnO/SnO2 PREPARATION electron microscopy X-ray diffraction
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Analysis of the Mechanical Properties of the Sintered Composite FeCuC in Two Different Atmospheres
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作者 Clayton Andre de Oliveira Motta Jose de Souza +5 位作者 Marcelo Salvador Coser Alex Fabiano Bueno Lirio Schaeffer Bernardo Poras Reis Hamudy Munir Abou Arabi Lucas Soares de Almeida 《Journal of Mechanics Engineering and Automation》 2015年第1期33-38,共6页
This study aimed to analyze the mechanical properties of the compound FeCuC when compacted at varying pressures and sintered in two different types of furnaces. Besides the different models of furnace, the working atm... This study aimed to analyze the mechanical properties of the compound FeCuC when compacted at varying pressures and sintered in two different types of furnaces. Besides the different models of furnace, the working atmospheres were varied: one is being composed with argon gas and another constituted with a balancing nitrogen and hydrogen. Atmospheres vary with the amount of production and the type of equipment used. The compound generated is used in the manufacture of rings for mechanical seals and is currently manufactured by the sintering process in passing furnace. The sintering was performed in a static furnace with argon atmosphere and compared with the same compound sintered in passage furnace with hydrogen and nitrogen atmosphere. The analysis of the properties of the tested material was performed with the aid of metallography using a scanning electron microscope, which verified the particle size distribution, chemical elements and pores present. Brinell hardness and Vickers micro hardness tests were also used to analyze the properties of this material after completion of the two processes. Thus, the research carried out has shown that variations may occur in the mechanical properties when processed in different furnace types and different sintering atmospheres. 展开更多
关键词 Sintering furnaces FeCuC work atmosphere
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