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61.
彩色数字全息研究中,用球面波为重建波及角谱衍射公式进行波前重建是一种有效的方法.然而,重建图像上通常伴有强烈的零级衍射干扰.本文通过理论分析,对波前重建过程作了重要改进.用改进后的方法进行彩色数字全息的实验研究表明,重建彩色图像的质量获得显著改善.
关键词:
彩色数字全息
波前重建
零级衍射干扰 相似文献
62.
The preparation and NMR analysis of 2,3-di-O-benzyl arabinofuranosides have been described. In DMSO-d6, the sugar adopts a conformation in which the hydroxyl groups are in an equatorial position; the equilibrium composition is determined by steric factors. In CDCl3, the sugar adopts a conformation in which the intramolecular hydrogen bonding plays an important role in determining the equilibrium composition. The use of 2,3-di-O-benzyl arabinose in the synthesis of oligoarabinofuranosides enabled the synthesis of α- or β-linked furanosides. 相似文献
63.
64.
Leyla Pehlivan Stéphane Laval Patrice Demonchaux Marc Lemaire 《Tetrahedron letters》2010,51(15):1939-10974
An efficient reduction of the nitro group with a catalytic amount of Fe(acac)3 and TMDS in THF at 60 °C affording the corresponding amine is described. 相似文献
65.
Hussein El-Kashef Pascal Rathelot Patrice Vanelle Sylvain Rault 《Monatshefte für Chemie / Chemical Monthly》2007,138(5):469-476
Summary. 2-Amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile was converted into the corresponding 2-(pyrrol-1-yl) derivative, followed by reduction of the latter
compound into the corresponding amine. This amine and its acyl, aroyl, and arylidene derivatives were used as synthons in
the synthesis of several title compounds. 相似文献
66.
67.
Multinuclear NMR spectroscopy, relaxation and diffusion measurements were used recently to extract dynamical information on the long-time mobility of the water molecules and the neutralizing counterions condensed within the electrostatic well in the vicinity of the basal surface of clay particles. Multi-scale numerical modeling was used to interpret the NMR relaxation measurements and illustrate the interdependency between the solvent and ionic mobility and the organization of the anisotropic clay particles within the colloidal dispersions. 相似文献
68.
Based on the studies of influence of YAG laser heating conditions for Al alloy melt and steel on wettability,the mechanics of the laser overlap braze welding of 6056 Al and XC18 steel sheet has been investigated.Under the temperature range which is above the melting point of the Al alloy and below the melting point of the steel, two dissimilar metals can be joined by means of laser braze welding. There is no crack observed in the joining area, i.e. Al-Fe intermetallic phase (Fe3Al/FeAl/FeAl3/Fe2Al5) layer formed by solution and diffusion between liquid-solid interface. The temperature range can be defined as the process temperatures of laser braze welding of Al-Fe materials. Selecting a higher laser heating temperature can improve the wettability of Al melt to steel surface, but the intermetallic phase layer is also thicker. When the laser heating temperature is so high that the joining surface of steel is melted, there is a crack trend in the joining area. 相似文献
69.
70.
This paper develops a theoretical analysis of a Bingham fluid in slipping squeeze flow. The flow field decomposition consists
in combining a central extensional flow zone in the plane of symmetry and shear flow zones near the plates. It is also considered
that the slipping zone is located around a central sticking zone as previously shown from experiments. It is assumed that
the shear stress at the plates is constant in the slipping zone and equals a fixed friction yield value. The squeeze force
required to compress a Bingham fluid under the slipping behaviour as well as the radial evolution of the transition point
between both sticking and slipping zones are finally determined. 相似文献