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111.
L.A. Bakaleynikov E.Yu. Flegontova E. Zolotoyabko 《Journal of Electron Spectroscopy and Related Phenomena》2006
Capabilities of the imaging techniques, in which X-rays are converted to electrons and then the emitted electrons are registered by means of an electron microscope, are analyzed, the focus being on the factors limiting lateral resolution at the stage of electron emission. Bearing in mind the tendency to use harder synchrotron X-rays for some combined X-ray-electron microscopy methods, calculations were made for two significantly different X-ray energies: E = 1.828 keV (K-edge of Si) and E = 11.923 keV (L3-edge of Au). By using Monte Carlo simulations of the electron trajectories beneath the surface of the sample we show that the radius of the spot from which photoelectrons are emitted could be as small as 1 nm. However, when proper account is taken of an entire electron cascade associated with the re-building of electron shells after photoelectron emission, spots more than one order of magnitude larger result, limiting the best lateral resolution to 20–30 nm. 相似文献
112.
The ability to quantitatively map the distribution of elements on the micrometer scale and smaller with high sensitivity and isotopic discrimination is unique to ion microscopy. The information contained in ion images can be crucial to the study of the solid state, where chemical heterogeneity is often directly related to observed behavior. The tools of digital image processing allow the extraction of quantitative information from the image data. These techniques coupled with improved instrumentation for the detection of ion images drastically increase the problem solving capabilities of the ion microscope. The use of such methods and instrumentation in the ion microscopic analyses of cell cultures and tissues of biological and biomedical relevance will be discussed. 相似文献
113.
本文主要阐述使用红外热象仪检测运行中的电力设备所发现的问题。文中通过若干实例介绍了用红外热象仪检测带电运行的发电机、电容器及连接头,并查出带有严重缺陷的部位,从而避免事故发生。 相似文献
114.
R. Rehm M. Walther J. Schmitz J. Fleißner F. Fuchs J. Ziegler W. Cabanski 《Opto-Electronics Review》2006,14(1):19-24
The first fully operational mid-IR (3–5 μm) 256×256 IR-FPA camera system based on a type-II InAs/GaSb short-period superlattice
showing an excellent noise equivalent temperature difference below 10 mK and a very uniform performance has been realized.
We report on the development and fabrication of the detecor chip, i.e., epitaxy, processing technology and electro-optical
characterization of fully integrated InAs/GaSb superlattice focal plane arrays. While the superlattice design employed for
the first demonstrator camera yielded a quantum efficiency around 30%, a superlattice structure grown with a thicker active
layer and an optimized V/III BEP ratio during growth of the InAs layers exhibits a significant increase in quantum efficiency.
Quantitative responsivity measurements reveal a quantum efficiency of about 60% for InAs/GaSb superlattice focal plane arrays
after implementing this design improvement.
The paper presented there appears in Infrared Photoelectronics, edited by Antoni Rogalski, Eustace L. Dereniak, Fiodor F. Sizov, Proc. SPIE Vol. 5957, 595707 (2005). 相似文献
115.
116.
Ken‐ichi Shinohara Tasuku Suzuki Takeshi Kitami Shingo Yamaguchi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(2):801-809
We fabricated a micrometer‐long supramolecular chain in which π‐conjugated polyrotaxane was coupled. A new experimental setup was designed and constructed, and the simultaneous direct imaging of the structure and fluorescent function was achieved. Furthermore, we identified the formation of a polymer intertwined network and observed novel fluorescence due to a long‐range interaction via this intertwined network over a distance of 5 μm or more without quenching over 15 min in the near field. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 801–809, 2006 相似文献
117.
Nianchen Zhou Wenjian Xu Yu Zhang Jian Zhu Xiulin Zhu 《Journal of polymer science. Part A, Polymer chemistry》2006,44(4):1522-1528
2,2,6,6‐Tetramethyl‐4‐[d‐(+)‐10‐camphorsulfonyl]‐1‐piperidinyloxy was synthesized and used as a chiral nitroxide for the bulk polymerizations of styrene initiated with benzoyl peroxide (BPO), tetraethylthiuram disulfide (TETD), and thermal initiation. The results showed that the polymerizations proceeded in a controlled/living way; that is, the kinetics presented approximately first‐order plots, and the number‐average molecular weights of the polymers with narrow molecular weight distributions (weight‐average molecular weight/number‐average molecular weight) increased with the monomer conversion linearly. The molecular weight distributions in the case of thermal initiation were narrower than those in the case of BPO and TETD, whereas the polymerization rate with BPO or TETD as an initiator was obviously faster than that with thermal initiation. In addition, successful chain‐extension reactions were carried out, and the structures of the obtained polymers were characterized by gel permeation chromatography and 1H NMR. The specific rotations of the polymers were also measured by polarimetric analysis. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1522–1528, 2006 相似文献
118.
高分子阳离子絮凝剂用于炼油废水处理研究 总被引:15,自引:0,他引:15
用聚二甲基二烯丙基氯化铵型高分子阳离子絮凝剂处理炼油废水考察了险油和化学耗氧量的动态变化规律。对产生的浮渣性质及滤饼的成份进行了研究。并且与聚合铝的处理效果进行对照。研究结果表明,HCA除油和化学耗管氧量的性能优于PAC,HCA产生的浮渣是PAC的三分之一,而浮渣中的含油量则是PAC的三倍。 相似文献
119.
三维立体成像及其应用 总被引:3,自引:0,他引:3
本文首先介绍了三种传统的主要三维立体成像方法,即透镜板三维成像方法,投影式三维显示和全息照相术,其次,重点对于采用计算机产生的三维立体景象的方法进行了综述,其中包括人们近年来研究较多的自动立体成像技术等,最后给出了三维立体成像技术在航空航天,工业,教育,医学,军事等领域的应用实例,并预测了三维立体成像技术今后的主要发展方向。 相似文献
120.
水下成像的现状和发展动向 总被引:5,自引:0,他引:5
本文以下水成像在军事,海洋开发工程应用为基础,论述了水下观测和成像中采用微光电视摄像机和激光器件及其系统的技术现状和发展动向。 相似文献