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981.
A new reconstruction method called sampled pattern matching (SPM) was applied to the image reconstruction of an electrical
capacitance computed tomography in powder flow in a vertical pipe for petroleum refinery process. This new method is able
to achieve stable convergence without the use of an empirical value. Experiments were carried out using fluid catalytic cracking
(FCC) catalysts as powder with two air volume flow rates and four powder volume flow rates to measure the capacitance of a
pipe cross section. The SPM method is compared with conventional methods in terms of volume fraction, residual capacitance,
and correlation capacitance. Overall, the SPM method proved superior to conventional methods without any empirical value because
SPM achieves accurate reconstruction by using an objective function that is calculated as the inner product calculation between
the experimental capacitance and the reconstructed image capacitance. 相似文献
982.
A numerical simulation code for three dimensional problems of near-field optics has been developed using the volume integral equation with the moment method. The object is assumed to be continuous and macroscopic dielectric and can be treated by macroscopic Maxwell#x0027;s equations. The code can treat the large-scale moment method matrix that is obtained by the discretization of the volume integral equation. The resultant matrix equation is solved by an iteration method called the generalized minimum residual method with reasonable computational cost for simple problems of near field optics. Simulation of a simplified model of a scanning near-field optical microscope has been performed and basic polarization characteristics of the system have been investigated in detail. The code is also applied to the collection-mode of a photon scanning tunneling microscope, where the incident wave is the evanescent wave, and basic relation between near-field and far field i.e., output image, is recognized. 相似文献
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Hiromitsu Kozuka Akihiro Yamano Masahiro Fujita Hiroaki Uchiyama 《Journal of Sol-Gel Science and Technology》2012,61(2):381-389
An aqueous dip-coating route without using volatile alcohols for preparing dense and porous silica thin films is presented.
The films were prepared by dip-coating on Si(100) and silica glass substrates using aqueous suspension of 8–11 nm colloidal
silica where no alcohols were added. The addition of polyvinylpyrrolidone (PVP) in the suspension greatly improved the wettability,
allowing homogeneous films to be formed on the substrates while the substrates showed poor wettability without PVP. When the
as-deposited films were fired at 500–1,000 °C, optically transparent porous films with smooth surface were obtained. The porous
films had homogeneous distribution and packing of silica nanoparticles, refractive indices of 1.24–1.33, and pencil hardness
lower than 6B. The porous films underwent significant densification by viscous sintering when fired at temperatures over 1,000 °C.
The viscous sintering was accompanied by the progress of condensation reaction and by the structural relaxation of siloxane
network, which was revealed in the infrared absorption spectra. The resulting dense films had optical transparency, smooth
surface, pencil hardness over 9H and refractive indices close to that of silica glass. 相似文献
986.
Masahiro Sugiura 《Synchrotron Radiation News》2013,26(6):34-36
What is an industrial researcher expecting from the use of synchrotron radiation at SPring-8? It seems that there are two answers. One expectation is that he is able to explain convincingly to his customers a distinctive advantage of the developed product in a visible manner, and the other is that he investigates essential quality of materials by returning to the starting point when he is at a loss what to do in the process of his R&D; thus he can gain the opportunity of making a technical breakthrough in his R&D. This is because SPring-8 provides the most powerful synchrotron radiation currently available. As a result, a researcher can understand the chemical-bonding states of the material structure at the atomic and electronic levels by utilizing new analytical tools such as XAFS (X-ray Absorption Fine Structure) and XRD (X-ray Diffraction), etc. 相似文献
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