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Min Wang Yuwan Cen Xiaofang Hu Xiaoliu Yu Nenggang Xie Yuguo Wu Peimin Xu Deyi Xu 《Optics & Laser Technology》2009,41(2):154-158
In the digital image correlation method, two steps are used to calculate the displacements of tested images. The first step is to locate the integer-pixel displacement, and the next one is to compute the sub-pixel displacement based on the first step. The benefit from the computation method for the integer-pixel displacement is that its results directly affect the displacement accuracy of each point in tested images. In this paper, a new method is developed to calculate the displacement fields between two images taken before and after deformation of an object. A new correlation function with a weighting factor related to the position of each point in the image is taken into account. The analysis and experimental results confirm the validity of the new method. In addition, the calculation results from our method have more accuracy than that of the traditional one. 相似文献
23.
Xiaogang Chen Zonglong Wang Deyi Chen 《International Journal of Infrared and Millimeter Waves》2008,29(4):424-431
The effects of direct current (dc) bias-drifting on radio on fiber (RoF) links are quantitative investigated and simulated.
Single sideband (SSB) modulation and carrier suppressed double sideband (CS-DSB) modulation RoF links are considered, power
variation of targeted signal and harmonic suppression on account for bias-drifting are calculated and evaluated. Our results
suggest that power variation can be maintained within 1.1 dB with dc bias drift ε less than 5% in the SSB modulation RoF link
and the degradation of harmonic suppression is evident with ε exceed 2% in the CS-DSB modulation RoF link. 相似文献
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通过改性由酸蚀二维蛭石制备的二维二氧化硅,得到带正电荷的二维介孔二氧化硅(PSN+)纳米片,并将PSN+用作聚环氧乙烷(PEO)基固体聚合物电解质(SPEs)的填料。由于PSN+具有丰富的正电荷,PSN+与锂盐解离的阴离子能够有效结合,从而促进锂离子的运输,获得较好的锂离子转移数。在50℃时,基于PSN+的SPEs表现出较高的离子电导率(7.5×10-5 S·cm-1),锂离子迁移数为0.30,稳定电压窗为4.41 V。因此,组装后的LiFePO4锂电池在50℃、0.2C下具有优异的初始放电比容量(155.7 mAh·g-1),在循环100次后容量保持率为97.1%。 相似文献
26.
Nanostructured epoxy thermoset templated by an amphiphilic PCL‐b‐PES‐b‐PCL triblock copolymer 下载免费PDF全文
Qilei Xu Quan Zhou Kang Shen Deyi Jiang Lizhong Ni 《Journal of Polymer Science.Polymer Physics》2016,54(3):424-432
The PCL‐b‐PES‐b‐PCL triblock copolymer is used to incorporate into epoxy resin when the blends are cured with 4,4'‐diaminodiphenylsulfone (DDS) to afford the nanostructured epoxy thermosets. The differential scanning calorimetry (DSC) and Fourier transform‐infrared spectroscopy (FT‐IR) show that the nanostructured PCL‐b‐PES‐b‐PCL thermosets are accessed through the formation of the intermolecular hydrogen bonding interactions. The nanostructures are further evidenced by means of small‐angle X‐ray scattering (SAXS) and transmission electron microscopy (TEM). By considering the miscibility of the subchains of block copolymer with epoxy before and after the curing reaction, it is judged that the formation of the nanostructures follows the mechanism of reaction‐induced microphase separation. It is noted that the epoxy resin is significantly toughened in terms of the measurement of critical stress field intensity factor (KIC). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 424–432 相似文献
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Zhang Yuanxun Gu Yingmei Li Deyi Zhu Xinfang Zhu Jieqing 《Journal of Radioanalytical and Nuclear Chemistry》2000,245(3):641-643
In order to develop new reference materials for microanalytical nuclear techniques, the Scanning Proton Microprobe (SPM) technique was used to determine homogeneity levels within 100×200 m2 micro-area on small pieces of IAEA Urban Dust reference materials. The experimental methods are described in detail. The results show that IAEA-396A/M Vienna Urban Dust is homogeneous enough for a SRM (10% for Si, S, K, Ca, Fe, Cu, Zn) for small sample analysis. 相似文献
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不同产地道地中药中元素含量的比较研究 总被引:1,自引:0,他引:1
研究了中药中微量元素Fe、Cu、Zn、Mn、Sr含量与产地的关系,结果表明,产地是影响中药中元素含量差异,也是影响中药质量的重要因素。 相似文献
30.
Seidel J Fu D Yang SY Alarcón-Lladó E Wu J Ramesh R Ager JW 《Physical review letters》2011,107(12):126805
We elucidate the mechanism of a newly observed photovoltaic effect which occurs in ferroelectrics with periodic domain structures. Under sufficiently strong illumination, domain walls function as nanoscale generators of the photovoltaic current. The steps in the electrostatic potential function to accumulate electrons and holes on opposite sides of the walls while locally reducing the concentration of the oppositely charged carriers. As a result, the recombination rate adjacent to the walls is reduced, leading to a net diffusion current. In open circuit, photovoltages for periodically ordered domain walls are additive and voltages much larger than the band gap can be generated. The internal quantum efficiency for individual domain walls can be surprisingly high, approaching 10% for above band-gap photons. Although we have found the effect in BiFeO(3) films, it should occur in any system with a similar periodic potential. 相似文献