近日,中国农业科学院北京畜牧兽医研究所鸡遗传育种科技创新团队研究发现新的促进禽流感病毒复制的宿主基因,揭示了禽流感病毒—鸡全基因组范围内蛋白功能性结合规律,为进一步解析鸡感染禽流感机制拓宽了思路。相关研究成果发表在《免...近日,中国农业科学院北京畜牧兽医研究所鸡遗传育种科技创新团队研究发现新的促进禽流感病毒复制的宿主基因,揭示了禽流感病毒—鸡全基因组范围内蛋白功能性结合规律,为进一步解析鸡感染禽流感机制拓宽了思路。相关研究成果发表在《免疫学前沿(Frontiers in Immunology)》上。展开更多
To figure out the distribution of temperature gradient along the girder height of steel-concrete composite box girder, combined with the mechanical characteristics of prestressed concrete composed box girder with corr...To figure out the distribution of temperature gradient along the girder height of steel-concrete composite box girder, combined with the mechanical characteristics of prestressed concrete composed box girder with corrugated steel webs, the calculation formulas of cross-sectional temperature stress along the span in a simply-supported beam bridge with composite section were derived under the conditions of static equilibrium and deformation compatibility of the beam element. The methods of calculating the maximum temperature stress value were discussed when the connectors are assumed rigid or flexible. Theoretical and numerical results indicate that the method proposed shows better precision for the calculation of temperature self-stress in both the top and the bottom surfaces of the box girder. Moreover, the regularity of temperature stress distribution at different locations along the girder span is that the largest axial force of the top or the bottom plate of the box girder is located in the midspan and spreads decreasingly until zero at both supported ends, and that the greatest longitudinal shear density in steel-concrete interface appears at both supported ends and then reduces gradually to zero in the midspan.展开更多
基金Supported by National Natural Science Foundation of China (No. 50978105)
文摘To figure out the distribution of temperature gradient along the girder height of steel-concrete composite box girder, combined with the mechanical characteristics of prestressed concrete composed box girder with corrugated steel webs, the calculation formulas of cross-sectional temperature stress along the span in a simply-supported beam bridge with composite section were derived under the conditions of static equilibrium and deformation compatibility of the beam element. The methods of calculating the maximum temperature stress value were discussed when the connectors are assumed rigid or flexible. Theoretical and numerical results indicate that the method proposed shows better precision for the calculation of temperature self-stress in both the top and the bottom surfaces of the box girder. Moreover, the regularity of temperature stress distribution at different locations along the girder span is that the largest axial force of the top or the bottom plate of the box girder is located in the midspan and spreads decreasingly until zero at both supported ends, and that the greatest longitudinal shear density in steel-concrete interface appears at both supported ends and then reduces gradually to zero in the midspan.
