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排序方式: 共有247条查询结果,搜索用时 343 毫秒
21.
Victor B. Tinti Debora Marani Andre S. Ferlauto Fabio C. Fonseca Vincenzo Esposito Daniel Z. de Florio 《Particle & Particle Systems Characterization》2020,37(2):1900472
A fast and accurate experimental method is demonstrated to assess the fraction of exsolved metallic nanoparticles using magnetic measurements. As a benchmark, nanometric metallic nickel exsolved from (La1−xSrx)(Cr1−yNiy)O3−δ is used for its high relevance as a solid oxide fuel cell component. The method is based on the difference in the magnetic response of the exsolved metallic nickel (ferromagnetic) and Sr-doped lanthanum chromite ceramic matrix (paramagnetic). The exsolved nickel results in coherent nanoparticles pinned on the surface of the Sr-doped lanthanum chromite ceramic matrix, as evidenced by electron microscopy analyses. The results obtained indicate the procedure as a fast and sensitive method to study the exsolution of ferromagnetic nanoparticles. 相似文献
22.
Structural properties of small aggregates containing up to 100 particles have been studied through detailed Monte Carlo cluster-cluster aggregation simulations in both diffusion-limited and reaction-limited conditions. First, the radius of gyration, the radius of the smallest sphere encompassing the cluster, and the particle-particle correlation function, g(r), have been computed based on the positions of all the particles in the cluster, and their fractal scaling has been analyzed. Then, an empirical model has been developed to simulate the g(r) function for aggregates of any size and used to determine the corresponding structural properties and scattering structure factors. Finally, in order to illustrate the application of the structural properties thus computed, two experiments on diffusion-limited aggregation have been performed, and the average scattering structure factors have been measured as a function of time using a small-angle light-scattering device. The obtained average scattering structure factors have been simulated using the Smoluchowski population balance equations, using the single aggregate structural properties and scattering structure factor predicted by the developed empirical g(r) model. 相似文献
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Corrigendum: Effect of hexyl substituent groups on photophysical and electrochemical properties of the poly[(9,9‐dioctyfluorene)‐2,7‐Diyl‐alt‐(4,7‐bis (3‐hexylthien‐5‐Yl)‐2,1,3‐benzothiadiazole)‐2′,2″‐diyl]
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25.
We consider the Cauchy problem for the 2×2 nonstrictly hyperbolic system
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V. Scuderi M. Zadro A. Di Pietro P. Figuera M. Lattuada F. Pansini M. Papa D. Vinciguerra O. Yu. Goryunov A. Khouaja V. Lyapin C. Nociforo V. V. Ostashko 《The European physical journal. Special topics》2007,150(1):53-54
The resonance scattering method in inverse kinematics on infinite target has been applied to two systems, 18O + α and 9Be + α, in order to test and to optimize an experimental apparatus in view of a set of resonance scattering experiments to
be performed with 8Li and 9Li radioactive ion beams delivered by the facility EXCYT. The scattering excitation functions, deduced for the two systems,
were compared with previous results reported in literature. Results show that reliable stopping power data are essential for
the application of this technique. 相似文献
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Juliana S Luz Celso RR Ramos Márcia CT Santos Patricia P Coltri Fernando L Palhano Debora Foguel Nilson IT Zanchin Carla C Oliveira 《BMC biochemistry》2010,11(1):22
Background
The archaeal exosome is formed by a hexameric RNase PH ring and three RNA binding subunits and has been shown to bind and degrade RNA in vitro. Despite extensive studies on the eukaryotic exosome and on the proteins interacting with this complex, little information is yet available on the identification and function of archaeal exosome regulatory factors. 相似文献29.
Human movement, as for example human gait, can be considered as an optimal realization of some given task. However, the criterion for which the naturally performed human motion is optimal, is generally not known. In this article we formulate an inverse optimal control problem to study the relevance of four different optimization criteria in human locomotion. As a walking model we use an actuated three dimensional spring loaded inverted pendulum (3D-SLIP), which is able to mirror the typical shape of the center of mass trajectory in human gait. Using a direct all-at-once approach, the weighting of the optimization criteria and the position of the footsteps are optimized in such a way, that the center of mass trajectory of the resulting optimal state fits real motion capture data as good as possible. Numerical experiments show, that whereas the so called capture point seems to have a great impact on human walking, minimization of the vertical center of mass movement does not show any relevance at all. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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