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991.
Shirazi Muhammad Faizan Wijesinghe Ruchire Eranga Ravichandran Naresh Kumar Kim Pilun Jeon Mansik Kim Jeehyun 《Optical Review》2017,24(2):219-225
Optical Review - A dual-path handheld system is proposed for cornea and retina imaging using spectral domain optical coherence tomography. The handheld sample arm is designed to acquire two images... 相似文献
992.
Nonlinear Dynamics - This paper investigates the problem of stabilization for sampled-data neural-network-based systems under variable sampling. A novel Lyapunov–Krasovskii functional (LKF)... 相似文献
993.
Solution properties,unperturbed dimensions,and chain flexibility of poly(1‐adamantyl acrylate)
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Wei Lu Panchao Yin Masashi Osa Weiyu Wang Nam‐Goo Kang Kunlun Hong Jimmy W. Mays 《Journal of Polymer Science.Polymer Physics》2017,55(20):1526-1531
Poly(1‐adamantyl acrylate) (PAdA) exhibits much higher glass transition and degradation temperatures than other polyacrylates. However, the quantitative evaluation of the stiffness of this polymer chain has not been reported previously. In this study, the dilute solution properties and conformational characteristics of PAdA were evaluated using viscometry and scattering techniques. The unperturbed dimensions of this polymer were evaluated using the Burchard–Stockmayer–Fixman extrapolation and the touched‐bead wormlike chain model. The PAdA chain has a comparable persistence length, diameter per bead and characteristic ratio to poly(methyl methacrylate) and polystyrene. All these results indicate that PAdA is less flexible than common polyacrylates. In addition, the second virial coefficients (A2) of PAdA in different solvents obtained by static light scattering were compared. Among the solvents investigated, tetrahydrofuran is a moderate solvent. Radius of gyration of a polymer sample in the various solvents ranged from 16.8 to 30.3 nm. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1526–1531 相似文献
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995.
The design variable tolerance effects on the natural frequency variance of constrained multi-body systems in dynamic equilibrium are investigated in this study. Monte-Carlo simulation is often employed for such investigations, but it is known to have serious drawbacks. Excessive amount of computation time needs to be consumed since a large number of evaluations are usually required for the method. Furthermore, the solution accuracy cannot be always guaranteed in spite of the excessive amount of computation time. In order to overcome such drawbacks, a method employing eigenvalue sensitivity information is proposed to obtain the variance of natural frequency in this study. In order to verify the accuracy and the efficiency of the method, some numerical examples of multi-body systems in dynamic equilibrium are solved and the results are compared to those obtained by an analytical method and Monte-Carlo simulation. 相似文献
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997.
Yang?LiuEmail author Yanwei?Du Hong?Li Jinfeng?Wang 《Journal of Applied Mathematics and Computing》2015,47(1-2):103-117
In this article, an \(H^1\)-Galerkin mixed finite element (MFE) method for solving time fractional reaction–diffusion equation is presented. The optimal time convergence order \(O(\varDelta t^{2-\alpha })\) and the optimal spatial rate of convergence in \(H^1\) and \(L^2\)-norms for variable \(u\) and its gradient \(\sigma \) are derived. Moreover, some numerical results are shown to support our theoretical analysis. 相似文献
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Hua Fang Weizhu Chen Bihong Hong Yufen Zhao Meijuan Fang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2182-2193
This article describes the synthesis of α-hydroxyphosphonic acid esters using the Pudovik reaction. IR, 1H NMR, 13C NMR, 31P NMR, MS, and elemental analysis were employed to confirm their structures. X-ray structure analysis is reported for six compounds. The antibacterial activities of these compounds are also reported. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献