Bending behavior test and assessment for full-scale PC box girder reinforced by prestressed CFRP plate

This paper focuses on behavior of full scale prestressed concrete (PC) box girder with difference degrees of damage derived from service stage. According to typical structural damage, strengthening measures are proposed, including gluing steel plate, gluing prestressed CFRP plate and so on. In order to testify the effectiveness of reinforced method, bending behavior test are conducted for full scale PC box girder both before and after strengthening. After the test, the bending behaviors of test girder are comparatively analyzed, and the failure mechanism of test girder reinforced by prestressed CFRP plate is studied. What’s more, the strengthening method of gluing prestressed CFRP plate is applied in in-situ prestressed concrete box girder bridge with obvious damage. The static and dynamic testing of this reinforced bridge shows the feasibility and effectiveness of gluing prestressed CFRP plate strengthening method. Studies in this paper provide reliable guidance for engineering application

Self-Dual Vortices in the Fractional Quantum Hall System

Based on the $\phi$-mapping theory, we obtain an exact Bogomol'nyi self-dual equation with a topological term, which is ignored in traditional self-dual equation, in the fractional quantum Hall system. It is revealed that there exist self-dual vortices in the system. We investigate the inner topological structure of the self-dual vortices and show that the topological charges of the vortices are quantized by Hopf indices and Brouwer degrees. Furthermore, we study the branch processes in detail. The vortices are found generating or annihilating at the limit points and encountering, splitting or merging at the bifurcation points of the vector field $\vec\phi$.Comment: 13 pages 10 figures. accepted by IJMP

Fermionic zero modes in self-dual vortex background

We study fermionic zero modes in the background of self-dual vortex on a two-dimensional non-compact extra space in 5+1 dimensions. In the Abelian Higgs model, we present an unified description of the topological and non-topological self-dual vortex on the extra two dimensions. Based on it, we study localization of bulk fermions on a brane with inclusion of Yang-Mills and gravity backgrounds in six dimensions. Through two simple cases, it is shown that the vortex background contributes a phase shift to the fermionic zero mode, this phase is actually origin from the Aharonov-Bohm effect.Comment: 11 pages, no figures, to appear in MPL

Fermionic zero modes in gauge and gravity backgrounds On T2T^2

In this note we study fermionic zero modes in gauge and gravity backgrounds taking a two dimensional compact manifold $T^2$ as extra dimensions. The result is that there exist massless Dirac fermions which have normalizable zero modes under quite general assumptions about these backgrounds on the bulk. Several special cases of gauge background on the torus are discussed and some simple fermionic zero modes are obtained.Comment: 8 pages, no figures, v2: more references, accepted by Mod.Phys.Lett.

Hopf bifurcation analysis in a neutral predator-prey model with age structure in prey

We show a detailed study on the dynamics of a neutral delay differential population model with age structure in the prey species. By selecting the mature delay as a bifurcation parameter, we obtain the stability and Hopf bifurcations of the coexistence equilibrium. Moreover, by computing the normal form on the center manifold, we give the formulas determining the stability of periodic solutions and the direction of Hopf bifurcation. Finally, we give some numerical simulations to support and strengthen the theoretical results

Hopf bifurcation analysis in a neutral predator–prey model with age structure in prey

We show a detailed study on the dynamics of a neutral delay differential population model with age structure in the prey species. By selecting the mature delay as a bifurcation parameter, we obtain the stability and Hopf bifurcations of the coexistence equilibrium. Moreover, by computing the normal form on the center manifold, we give the formulas determining the stability of periodic solutions and the direction of Hopf bifurcation. Finally, we give some numerical simulations to support and strengthen the theoretical results

Knotted Solitons in a Charged Two-Condensate Bose System

By making use of the decomposition of U(1) gauge potential theory and the \phi mapping method, we propose that a charged two-condensate Bose system possesses vortex lines and two classes of knotted solitons. The topological charges of the vortex lines are characterized by the Hopf indices and the Brower degrees of \phi-mapping, and the knotted solitons are described by the nontrivial Hopf invariant and the BF action, respectively.Comment: 12 pages,0 figure

A facile one-pot synthesis of CaO/CuO hollow microspheres featuring highly porous shells for enhanced CO2 capture in combined Ca-Cu looping process via a template-free synthesis approach

The preparation of bifunctional CaO/CuO composites with high performance is essential for the development of the combined Ca–Cu looping process, in which the exothermic reduction of CuO with methane is used in situ to provide the heat required to calcine CaCO3. However, the rapid decline in CO2 uptake of CaO/CuO composites remains an important problem to be solved, despite their excellent redox characteristic. Herein we report a facile one-pot template-free synthesis approach to yield CaO/CuO hollow microspheres, aimed at enhancing the CO2 capture performance of CaO/CuO composites. CaO/CuO hollow microspheres feature highly porous shells and a homogeneous elemental distribution, and demonstrate significantly enhanced CO2 capture performance. After ten repeated cycles in a fixed-bed reactor, the CO2 uptake capacity of the best-performing CaO/CuO hollow microspheres exceeded that of the reference materials, i.e., CaO/CuO composites synthesized via wet mixing or a co-precipitation method, by 222% and 114%, respectively. Moreover, from cycle number eight onwards, the CO2 uptake was very stable over the tested 20 cycles, suggesting good cyclic stability of CaO/CuO hollow microspheres. Oxidation was always fast with O2 uptake capacities greater than 0.13 gO2 gmaterial−1. On the basis of N2 adsorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations, the significantly enhanced CO2 capture performance of the CaO/CuO hollow microspheres resulted from the unique hollow microsphere structure with highly porous shells, which were retained throughout the cyclic operations