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991.
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We define the “localized index” of longitudinal elliptic operators on Lie groupoids associated with Lie algebroid cohomology classes. We derive a topological expression for these numbers using the algebraic index theorem for Poisson manifolds on the dual of the Lie algebroid. Underlying the definition and computation of the localized index, is an action of the Hopf algebroid of jets around the unit space, and the characteristic map it induces on Lie algebroid cohomology. This map can be globalized to differentiable groupoid cohomology, giving a definition of the “global index”, that can be computed by localization. This correspondence between the “global” and “localized” index is given by the van Est map for Lie groupoids. 相似文献
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Minghua Min Yuyuan Shi Haiyou Ma Hongliang Huang Jiangao Shi Xiaoxue Chen 《Journal of Macromolecular Science: Physics》2015,54(4):411-423
The effects of addition of synthesized organic-suspension silver nanoparticles on the crystallization and thermal stability of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were studied by transmission electron microscopy (TEM), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (XRD), UV-Vis absorption spectroscopy, polarized optical microscopy (POM), and thermal gravimetric analysis (TGA). The TEM images showed the average primary size of the as-synthesized silver nanoparticles, coated with a monolayer of the surfactants consisting of oleic acid and an alkylamine, was about 5 nm with narrow distribution, and that they were uniformly dispersed in n-heptane. PHBV/silver nanocomposites were prepared by melt mixing in an internal mixer and then injection molded into rectangle-shaped specimens by a labscale injection molding device. The coated silver nanoparticles showed a homogenuous dispersion in the PHBV matrix when the content of coated silver nanoparticles was about 1%. Both the DSC and POM data showed the efficient heterogeneous nucleation by the coated silver nanoparticles for facilitating PHBV crystallization. The thermal stability of the PHBV/silver nanocomposites improved with the increase in the content of the coated silver nanoparticles. 相似文献
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The effect of Fe on the phase and magnetocaloric property of LaFe11.6*xSi1.4B0.1 alloys with x = 1.0–1.4 have been studied. The results show that the excess of Fe will make the α-Fe phases increase, but the easy corrosion LaFeSi phase reduces in LaFe11.6*xSi1.4B0.1 alloys. All LaFe11.6*xSi1.4B0.1 alloys keep the first-order magnetic phase transition. The saturation magnetizations of LaFe11.6*xSi1.4B0.1 alloys with x > 1 are much higher than LaFe11.6Si1.4B0.1 alloy under 2T magnetic field. This results in the maximum isothermal magnetic entropy changes, and the relative cooling power of LaFe11.6*xSi1.4B0.1 alloys is bigger than for LaFe11.6Si1.4B0.1 alloys. 相似文献
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A novel imaging tool for hepatic portal system using phase contrast technique with hydrogen peroxide‐generated O2 gas 下载免费PDF全文
Rongbiao Tang Fuhua Yan Wei‐Min Chai Wei Huang Yanan Fu Guo‐Yuan Yang Ke‐Min Chen 《Journal of synchrotron radiation》2015,22(5):1263-1267
The objective of this study was to investigate the potential of hydrogen peroxide‐generated oxygen gas‐based phase contrast imaging (PCI) for visualizing mouse hepatic portal veins. The O2 gas was made from the reaction between H2O2 and catalase. The gas production was imaged by PCI in real time. The H2O2 was injected into the enteric cavity of the lower sigmoid colon to produce O2 in the submucosal venous plexus. The generated O2 gas could be finally drained into hepatic portal veins. Absorption contrast imaging (ACI) and PCI of O2‐filled portal veins were performed and compared. PCI offers high resolution and real‐time visualization of the O2 gas production. Compared with O2‐based ACI, O2‐based PCI significantly enhanced the revealing of the portal vein in vivo. It is concluded that O2‐based PCI is a novel and promising imaging modality for future studies of portal venous disorders in mice models. 相似文献
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