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Yanying Li Qiwen Zhang Xiaoran Zhao Haofei Wu Xinyao Wang Yuqiao Zeng Qing Chen Mingwei Chen Pan Liu 《Advanced functional materials》2023,33(17):2370105
The development of low-cost and effective oxygen evolution reaction (OER) electrocatalysts to expedite the slow kinetics of water splitting is crucial for increasing the efficiency of energy conversion from electricity to hydrogen fuel. Herein, 3D bicontinuous nanoporous Co@CoO/RuO2 composites with tunable sizes and chemical compositions are fabricated by introducing vapor phase dealloying of cobalt-based alloys. The influence of physical parameters on the formation of nanoporous Co substrates with various feature ligament sizes is systematically investigated. The CoO/RuO2 shell is constructed by integrating a thin layer of RuO2 on the inner surface of nanoporous Co, where the CoO interlayer is formed by annealing oxidization. The composite catalyst delivers an ultralow overpotential of 198 mV at 10 mA cm−2, Tafel slope of 57.1 mV dec−1, and long-term stability of 50 h. The superior OER activity and fast reaction kinetics are attributed to charge transfer through the coupling of Co O Ru bonds at the interface and the excellent nanopore connectivity, while the durability originates from the highly stable CoO/RuO2 interface. 相似文献
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Sarv Ahrabi Sima Piazzo Lorenzo Momenzadeh Alireza Scarpiniti Michele Baccarelli Enzo 《The Journal of supercomputing》2022,78(9):12024-12045
The Journal of Supercomputing - We present a probabilistic method for classifying chest computed tomography (CT) scans into COVID-19 and non-COVID-19. To this end, we design and train, in an... 相似文献
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H Ristic S Srinivasan KE Hall AA Sima JW Wiley 《Canadian Metallurgical Quarterly》1998,80(3):1236-1244
We examined the hypothesis that exposure of nondiabetic rat dorsal root ganglion (DRG) neurons to sera from diabetic BB/W rats would produce an increase in calcium currents associated with impaired regulation of the inhibitory G protein-calcium channel complex. Acutely dissociated rat DRGs were incubated for 18-24 h in medium supplemented with sera (10% vol/vol) from either diabetic rats with neuropathy or age-matched, nondiabetic controls. Exposure of DRG neurons to sera from diabetic BB/W rats resulted in a surface membrane immunofluorescence pattern when treated with an anti-rat light-chain antibody that was not observed in neurons exposed to control sera. Calcium current density (IDCa) was assessed with the use of the whole cell variation of the patch-clamp technique. IDCa in neurons exposed to diabetic sera was significantly increased compared with neurons exposed to control sera. Guanine nucleotide-binding (G) protein regulation of calcium channel function was examined with the use of a two-pulse "facilitation" or IDCa enhancement protocol in the presence of activators [guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S)] or antagonists [guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) and pertussis toxin (PTX)] of G protein function. Facilitation was significantly decreased in neurons exposed to diabetic sera. Intracellular diffusion of neurons with GDP beta s blocked facilitation, whereas dialysis with GTP gamma s increased facilitation to a similar magnitude in neurons exposed to either diabetic or control sera. Treatment with PTX resulted in a significant increase in IDCa and approximately 50% decrease in facilitation in neurons treated with control sera but no significant changes in neurons exposed to diabetic sera. We conclude that serum from diabetic BB/W rats with neuropathy contains an autoimmune immunoglobulin that impairs regulation of the inhibitory G protein-calcium channel complex, resulting in enhanced calcium influx. Regulation of the inhibitory G protein-calcium channel complex involves PTX-sensitive and -insensitive G proteins. 相似文献
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Image variability that is impossible or difficult to restore by intra-image processing, such as the variability caused by occlusions, significantly reduces the performance of image-recognition methods. To address this issue, we propose that the pixels associated with large distances obtained by inter-image pixel-by-pixels comparisons should be considered as inter-image outliers and should be removed from the similarity calculation used for the image classification. When this method is combined with the template-matching method for image recognition, it leads to state-of-the-art recognition performance: 91% with AR database that includes occluded face images, 90% with PUT database that includes pose variations of face images and 100% with EYale B database that includes images with large illumination variation. 相似文献
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The cost of servicing a warranty depends, amongst other factors, on the type of repair performed under warranty. Although “all minimal repair” and “all replacement” policies are easy to implement and analyze, they are not always feasible and/or practical. Having a combination of different types of repair often leads to lower warranty servicing costs. In this article, to reduce the warranty servicing cost, we study a servicing strategy that involves performing imperfect repairs in place of some of the minimal repairs of an “all minimal repair” strategy; the effect of an imperfect repair is characterized by a drop in the conditional intensity function of the failure process. We consider both fixed and random degrees of repair. For a given type of product, we partition the warranty region so that the expected total warranty servicing cost is minimized. We provide a numerical illustration and a comparison with previously-studied repair-replacement strategies. 相似文献
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Gopalan R Taheri S Turaga P Chellappa R 《IEEE transactions on pattern analysis and machine intelligence》2012,34(6):1220-1226
Understanding the effect of blur is an important problem in unconstrained visual analysis. We address this problem in the context of image-based recognition by a fusion of image-formation models and differential geometric tools. First, we discuss the space spanned by blurred versions of an image and then, under certain assumptions, provide a differential geometric analysis of that space. More specifically, we create a subspace resulting from convolution of an image with a complete set of orthonormal basis functions of a prespecified maximum size (that can represent an arbitrary blur kernel within that size), and show that the corresponding subspaces created from a clean image and its blurred versions are equal under the ideal case of zero noise and some assumptions on the properties of blur kernels. We then study the practical utility of this subspace representation for the problem of direct recognition of blurred faces by viewing the subspaces as points on the Grassmann manifold and present methods to perform recognition for cases where the blur is both homogenous and spatially varying. We empirically analyze the effect of noise, as well as the presence of other facial variations between the gallery and probe images, and provide comparisons with existing approaches on standard data sets. 相似文献
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本文针对刚性防水屋面渗漏的原因进行了分析,并提出了处理措施,旨在控制刚性防水屋面渗漏的产 生,保证屋面质量,满足使用要求。 相似文献