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21.
The security of the quantum secret key plays a critical role in quantum communications.Thus far,one problem that still exists in existing protocols is the leakage of the length of the secret key.In this letter,based on variable quantum encoding algorithms,we propose a secure quantum key distribution scheme,which can overcome the security problem involving the leakage of the secret key.Security analysis shows that the proposed scheme is both secure and effective. 相似文献
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The encapsulation of C60 into single-wall carbon nanotubes is systematically studied by tight-binding molecular dynamics method with an appropriate long-range Lennard-Jones potentials. For a (16,0) nanotube, it is impossible to encapsulate C60 into the tube because of a much larger energy barrier with the relaxation of the open end. 相似文献
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Least‐squares mixed finite element schemes are formulated to solve the evolutionary Navier‐Stokes equations and the convergence is analyzed. We recast the Navier‐Stokes equations as a first‐order system by introducing a vorticity flux variable, and show that a least‐squares principle based on L2 norms applied to this system yields optimal discretization error estimates. © 2002 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 18: 441–453, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/num.10015 相似文献
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Haiming Wang 《Optics and Lasers in Engineering》1997,27(3):285-296
In scattering measurement it is important and also difficult to separate instrument scattering from the scattering of a sample. Particularly at angles near the specular reflection, it is believed that the small angle limit for scattering measurement is determined not only by detector proximity to the specular beam, but also by the sample scattering. When the scattering angles are smaller than a certain limit, the total scattering combining the instrument scattering and the sample scattering is lower than the instrument scattering. This prevents us from discriminating the instrument scattering and the sample scattering at angles smaller than this limit. In this paper a data processing method is reported that enables us to distinguish the instrument scattering at angles smaller than this limit. Based on this method, we can measure the scattering at angles restricted only by the performance of the instrument. 相似文献
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Haiming Chen Yuning Ma Ting Huang Chao Su Pei Liu Tongsheng Li 《Journal of Macromolecular Science: Physics》2013,52(11):1613-1625
Poly (amide-amidic acid) (PAA) was selected to modify diglycidyl ether of bisphenol-A (DGEBA)/4,4′-diaminodiphenylsulfone (DDS). The cure behavior was studied by means of nonisothermal differential scanning calorimeter (DSC) analysis, indicating that PAA played a role of catalyst during the process of the curing reaction. Results of Fourier transform infrared spectroscopy (FT-IR) analysis showed that the PAA acted as a co-curing agent when the PAA content was 3.2–38.4 phr and also as a modifier when the PAA content was 12.8–38.4 phr. The glass transition temperature (Tg ) decreased with the increase of PAA content. The thermal stability improved when the PAA content was 3.2–6.4 phr because of the catalytic effect of PAA. The flexural strength improved for the varying PAA content studied in this work, with the highest flexural strength being obtained when the PAA content was 6.4 phr. The fracture surface morphology was observed using scanning electron microscopy (SEM); the morphologies varied with changing content of PAA. 相似文献
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Qian Yi Qiao Peng Li Long Han Haoyue Zhao Rongmin Zhang Haiming 《Journal of Thermal Analysis and Calorimetry》2020,142(1):425-435
Journal of Thermal Analysis and Calorimetry - In this article, a pillared layered antimony hydroxide (Sb-LH) material has been prepared by the hydrothermal method. X-ray diffraction,... 相似文献