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91.
基于可靠性的相位去包裹算法   总被引:1,自引:0,他引:1  
郑刚  王文格  罗春红 《光学技术》2004,30(4):510-512
提出了一种新的基于可靠性的相位去包裹算法。采用了队列算法及去包裹可靠性的判别标准。与传统方法相比,能够自动避开噪声区域,解决了相位去包裹中的阴影遮挡以及空洞等问题,克服了传统去包裹方法中的误差传播效应,能准确快速地对全场进行相位去包裹。设计了一套基于此算法的三维形面测量系统。  相似文献   
92.
In this article a new technique was developed to fabricate scaffolds with a unique microstructure by solid–liquid separation in combination with particulate-leaching. Firstly, the effects of polymer concentration, quenching temperature on the porous morphology and the mechanical property of obtained scaffolds during solid–liquid separation have been investigated. Then, salt granules as porogen were introduced into the solid–liquid phase separation to produce the unique pore structure of the scaffold. The pore diameter of the scaffold could be controlled with the particulate size and the wall of pores possessed special microstructure, which enhanced the pore interconnectivity. The cell culture results confirmed that a good interconnectivity of the scaffold prepared by the improved solid–liquid separation was useful for nutrition transportation and cell proliferation. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
93.
A mapping from a subset of the real axis to a metric space with finite generalized variation is shown to admit extension to a mapping of the whole real axis with the same variation. This result leads to characterization of the generalized essential variation of a mapping.  相似文献   
94.
A cubic structure of polymer colloid complexes is studied. The technique of the research includes i) an analysis of well-known literature SAXS data; on this basis, ii) constructing a simple model to estimate geometric structure parameters and to obtain a simulated scattering curve; and iii) comparing the model with the real structure obtained from the SAXS data, using the reconstruction of electron density distribution. A bicontinuous structure in cubic mesophases is formed. Dedicated to the memory of Alexander T. Dembo  相似文献   
95.
The sterically stabilized emulsion polymerization of styrene initiated by a water‐soluble initiator at different temperatures has been investigated. The rate of polymerization (Rp) versus conversion curve shows the two non‐stationary‐rate intervals typical for the polymerization proceeding under non‐stationary‐state conditions. The shape of the Rp versus conversion curve results from two opposite effects—the increased number of particles and the decreased monomer concentration at reaction loci as the polymerization advances. At elevated temperatures the monomer emulsion equilibrates to a two‐phase or three‐phase system. The upper phase is transparent (monomer), and the lower one is blue colored, typical for microemulsion. After stirring such a multiphase system and initiation of polymerization, the initial coarse polymer emulsion was formed. The average size of monomer/polymer particles strongly decreased up to about 40% conversion and then leveled off. The initial large particles are assumed to be highly monomer‐swollen particles formed by the heteroagglomeration of unstable polymer particles and monomer droplets. The size of the “highly monomer” swollen particles continuously decreases with conversion, and they merge with the growing particles at about 40–50% conversion. The monomer droplets and/or large highly monomer‐swollen polymer particles also serve as a reservoir of monomer and emulsifier. The continuous release of nonionic (hydrophobic) emulsifier from the monomer phase increases the colloidal stability of primary particles and the number of polymer particles, that is, the particle nucleation is shifted to the higher conversion region. Variations of the square and cube of the mean droplet radius with aging time indicate that neither the coalescence nor the Ostwald ripening is the main driving force for the droplet instability. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 804–820, 2003  相似文献   
96.
纵波模拟演示装置   总被引:1,自引:1,他引:0  
路峻岭  汪荣宝 《物理实验》2003,23(11):31-32
介绍了一种纵波模拟演示装置,并给出了其结构要点及演示效果,实现了对纵波行波的演示。  相似文献   
97.
Shiyue Fang 《Tetrahedron letters》2004,45(43):7987-7990
A reversible biotinylation phosphoramidite was synthesized and incorporated onto the 5′-end of an oligoribonucleotide on a solid phase synthesizer. After cleavage and deprotection, the crude synthetic oligomer mixture was incubated with NeutrAvidin® coated microspheres, and the failure sequences removed by washing with a buffer followed by treating the microspheres with tetrabutylammonium fluoride to give a high quality unmodified full-length oligoribonucleotide.  相似文献   
98.
转动系统的相对论性分析力学理论   总被引:20,自引:3,他引:17  
本文讨论了转动相对论力学理论,主要是建立转动系统的相对论性分析力学理论·构造转动系统的相对论性广义动能函数Tr=∑ni=1I0iΓi2(1-1-θ·2i/Γi2)和广义加速度能量函数Sr=12∑ni=1Ii(θ·i·θ¨i)2Γi2-θ·2i+θ¨2i,给出其Hamilton原理和三种不同形式的D′Alembert原理;对于完整约束系统,建立了转动系统的相对论性Lagrange方程、Nielsen方程、Appel方程和Hamilton正则方程;对于非完整约束系统,建立了转动系统的相对论性Routh方程、Чаплыгин方程、Nielsen方程和Appel方程;并给出转动系统的相对论性Noether守恒律  相似文献   
99.
A method of simulated annealing in optimization of a computer generated holo-gram(CGH)is presented.The characteristics of energy in annealing curve are analyzed.Thecooling schedule such as giving an initial temperature,the temperature function,the numberof interactions and stopping criterion are discussed.As an example,an optimization of phaserelief kinoform,a CGH with multiple phase levels,is implemented.  相似文献   
100.
利用相位共轭技术补偿光纤中色散效应的条件   总被引:1,自引:0,他引:1  
利用相位共轭器的频率反转特性的,补偿光纤中的色散效应,在理论上和实验上得到了证明.由色散脉冲的傅里叶交换确定了光纤中二次色散效应可以被忽略的条件,得到了共轭器的反射率和带宽与非线性介质的长度L,参数|K|L之间的关系曲线,找到了影响补偿效果的主要因素.  相似文献   
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