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We describe the construction of a high performance parallel computer composed of PC components, presentsome physical results for light hadron and hybrid meson masses from lattice QCD. We also show that the smearingtechnique is very useful for improving the spectrum calculations. 相似文献
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We investigate the relationship between the structure and the synchronizability of scale-free networks in geographical space. With an optimization approach, the numerical results indicate that when the network synchronizability is improved, the geographical distance becomes larger while the maximal load decreases. Thus the maximal betweenness can be a candidate factor that affects the network synchronizability both in topological space and in geographical space. 相似文献
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Chun-Ye Zhang Xiang-Qian Shen Jian-Xin Zhou Mao-Xiang Jing Kai Cao 《Journal of Sol-Gel Science and Technology》2007,42(1):95-100
Functional spinel ferrite fibers are attractive for high-tech applications. The spinel NiFe2O4 fibres have been successfully prepared by the organic gel-thermal decomposition process from raw materials of Ni, Fe nitrate
salts and citric acid. The gel spinning performance was a major factor for preparation of uniform gel fibrous precursors.
The gel spinnability was related to the citrate-metal complex structure and linear-type structural molecules [(C6H6O7)4NiFe2]n for the gel precursor was possibly formed during the complexation reaction between the citric acid and metal ions at pH 5.
The composition, structure of the gel precursors and products derived from thermal decomposition of these precursors were
characterized by FTIR, XRD, and SEM. The thermal decomposition process of the gel precursors was investigated by TG-DSC. The
prepared spinel NiFe2O4 fibres having grain sizes of 60–70 nm were featured with diameters of about 1 μm, and aspect ratios up to 106 (length/diameter). 相似文献
57.
在单目标、单约束条件下,建立了三状态并-串联系统的优化模型,采用选取重要部件的方法优化系统可靠度,并相应地给出优化算法,最后通过例子,验证了该算法的有效性. 相似文献
58.
钛硅分子筛TS-1的快速合 总被引:4,自引:0,他引:4
quick synthesis, titanium silicalite-1, anatase titania, propylene, epoxidation, hydrogen peroxide 相似文献
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Mn0.5Zn0.5Fe2O4 Magnetic nanofibers were fabricated by calcining electrospun polymer/inorganic composite nanofibers and characterized by thermogravimetric and differential thermal analysis, x-ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy and a vibrating sample magnetometer. The experimental results show that the pure spinel structure is basically formed when the composite nanofibers are calcined at 450°C for 2h. With the increasing calcination temperature, both the saturation magnetization and coercivity of nanofiber samples increase initially along with the growth of Mn0.5Zn0.5Fe2O4 nanocrystals contained in the nanofibers. However, when the calcination temperature reaches 550°C, the saturation magnetization of nanofibers starts to dramatically decrease owing to the formation of the α-Fe2O3 phase at this temperature. The prepared Mn0.5Zn0.5Fe2O4 nanofibers calcined at 500°C for 2h have diameters ranging from 100 to 200nm. Their saturation magnetization and coercivity are 12.37emu/g and 4.81kA/m at room temperature, respectively. 相似文献