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71.
We propose an asymmetric integral imaging method to adjust the resolution and depth of a three‐dimensional image. Our method is obtained by use of two lenticular sheets with different pitches fabricated under the same F/#. The asymmetric integral imaging is the generalized version of integral imaging, including both conventional integral imaging and one‐dimensional integral imaging. We present experimental results to test and verify the performance of our method computationally.  相似文献   
72.
In this paper, the microstructure of a 1 wt.% Cu/γ-Al2O3 catalyst that was reduced in a 4% hydrogen/argon atmosphere at temperatures of 523, 773 and 1073 K, is studied by Z-contrast imaging and electron energy-loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM). Results show that the copper species are well dispersed when the catalyst is reduced below 523 K. At 773 K, separated Cu(I) and Cu(0) species are found existing as ring-like and bulk-like particles. This appears to indicate that the copper has not been reduced to its metallic form due to the interaction between the copper oxide and the support. Large spherical particles having core-shell structures with Cu(I) in the shells and Cu(0) in the cores are generated when the catalyst is reduced at 1073 K. The formation of partially oxidized copper species upon reduction at 1073 K is attributed to the metallic copper interaction with the alumina support. This study also demonstrates that high-spatial resolution Z-contrast imaging and EELS performed simultaneously can provide unique information on the morphology and chemistry of metal species in supported metal catalysts.  相似文献   
73.
机载扫描成象系统的技术发展   总被引:4,自引:1,他引:3  
叙述了机载扫描成象系统的发展,基本结构,特点及其应用.  相似文献   
74.
张强  梁甸农  董臻 《无线电工程》2006,36(5):39-41,49
弹载条带式SAR信号特点表现为小的距离弯曲量,当分辨率要求不是特别高时,若最大距离弯曲量小于一个距离分辨单元时可忽略不计,而只考虑距离走动量的校正。针对这一特点提出了一种在频域对距离迁移的线性项即距离走动校正的成像方法,并提出了距离误差校正和图像几何校正相结合的方法,使得成像效率更高。仿真成像结果验证了该方法的可行性。  相似文献   
75.
Representative and quantitative microstructural information of cement-based materials can be obtained in the backscattered electron and X-ray modes of the scanning electron microscope (SEM). One prerequisite, of several, is to use flat specimens. Microstructures that are minimally affected by the grinding and polishing necessary to produce the flat surface can be obtained. It is essential to fill the pores of the specimen with epoxy resin prior to grinding and polishing. After hardening, the epoxy stabilizes the microstructure and enables it to withstand the stresses of grinding and polishing without alteration. In the present paper, we describe a preparation technique that we consider to have produced excellent polished specimens. The importance of epoxy impregnation is demonstrated.  相似文献   
76.
Dipti Biswal 《Polymer》2006,47(21):7355-7360
A novel application of FTIR imaging for real-time characterization of patterning polymerization processes with microscale spatial resolution is presented. These methods will enable the microscale analysis of the reactions of polymeric systems with various substrates and devices. Specifically, intelligent hydrogels containing ionic groups (pH responsive) and poly(ethylene glycol) have been micropatterned onto gold surfaces, and the free-radical polymerization reaction has been characterized. It was demonstrated that differences in the reaction rates across a patterned region could be successfully resolved and characterized. This novel characterization method based on FTIR imaging will facilitate the optimization of integration processes of patterned polymeric films leading to enhanced (and reproducible) application of these materials as functional components in a variety of microdevices.  相似文献   
77.
The objective of this research is to develop a non-destructive method for predicting cooked beef tenderness using optical scattering of light on fresh beef muscle tissue. A hyperspectral imaging system (λ = 496–1,036 nm) that consists of a CCD camera and an imaging spectrograph, was used to acquire beef steak images. The hyperspectral image consisted of 120 bands with spectral intervals of 4.54 nm. Sixty-one fresh beef steaks, including 44 strip loin and 17 tenderloin cuts, were collected. After imaging, the steaks were cooked and Warner-Bratzler shear (WBS) force values were collected as tenderness references. The optical scattering profiles were derived from the hyperspectral images and fitted to the modified Lorentzian function. Parameters, such as the peak height, full scattering width at half maximum (FWHM), and the slope around the FWHM were determined at each wavelength. Stepwise regression was used to identify 7 key wavelengths and parameters. The parameters were then used to predict the WBS scores. The model was able to predict WBS scores with an = 0.67. Optical scattering implemented with hyperspectral imaging shows limited success for predicting current status of tenderness in beef steak.  相似文献   
78.
79.
张斧 《激光与红外》1994,24(1):23-26
本文分析与阐述了成像光谱技术发展的科学背景与现状。  相似文献   
80.
本文简述了红外热成像技术用于厚膜混合集成电路热设计中的理论与实验方法,并讨论了结果。  相似文献   
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