为获得铰接中心支撑框架结构体系的抗震性能,以位于抗震设防烈度8度区的某大型火电厂钢结构主厂房横向最不利一榀的煤仓间部分为原型,按1∶12缩尺比例设计制作了试验模型,并对其进行了14种地震工况下的模拟地震作用振动台试验。得到了...为获得铰接中心支撑框架结构体系的抗震性能,以位于抗震设防烈度8度区的某大型火电厂钢结构主厂房横向最不利一榀的煤仓间部分为原型,按1∶12缩尺比例设计制作了试验模型,并对其进行了14种地震工况下的模拟地震作用振动台试验。得到了模型结构的动力特性、阻尼比及其在8度多遇、基本和罕遇烈度下的加速度和位移响应等。结果表明:8度多遇地震作用前后结构第1阶频率为4.59Hz,8度罕遇地震作用后,第1阶频率减小为4.40Hz,但梁柱仍然完好,仅有个别支撑和节点板出现了微小的平面外变形。依据试验与有限元分析结果,推算出试验原型结构在三种地震(E l Centro、CholamShandon、人工地震)的多遇烈度以及人工地震的罕遇烈度下,层间位移角均满足我国现行抗震规范要求。该体系在高烈度区也可具有良好的抗震性能。展开更多
Auxin is a key hormonal regulator,that governs plant growth and development in concert with other hormonal pathways.The unique feature of auxin is its polar,cell-to-cell transport that leads to the formation of local ...Auxin is a key hormonal regulator,that governs plant growth and development in concert with other hormonal pathways.The unique feature of auxin is its polar,cell-to-cell transport that leads to the formation of local auxin maxima and gradients,which coordinate initiation and patterning of plant organs.The molecular machinery mediating polar auxin transport is one of the important points of interaction with other hormones.Multiple hormonal pathways converge at the regulation of auxin transport and form a regulatory network that integrates various developmental and environmental inputs to steer plant development.In this review,we discuss recent advances in understanding the mechanisms that underlie regulation of polar auxin transport by multiple hormonal pathways.Specifically,we focus on the post-translational mechanisms that contribute to fine-tuning of the abundance and polarity of auxin transporters at the plasma membrane and thereby enable rapid modification of the auxin flow to coordinate plant growth and development.展开更多
文摘为获得铰接中心支撑框架结构体系的抗震性能,以位于抗震设防烈度8度区的某大型火电厂钢结构主厂房横向最不利一榀的煤仓间部分为原型,按1∶12缩尺比例设计制作了试验模型,并对其进行了14种地震工况下的模拟地震作用振动台试验。得到了模型结构的动力特性、阻尼比及其在8度多遇、基本和罕遇烈度下的加速度和位移响应等。结果表明:8度多遇地震作用前后结构第1阶频率为4.59Hz,8度罕遇地震作用后,第1阶频率减小为4.40Hz,但梁柱仍然完好,仅有个别支撑和节点板出现了微小的平面外变形。依据试验与有限元分析结果,推算出试验原型结构在三种地震(E l Centro、CholamShandon、人工地震)的多遇烈度以及人工地震的罕遇烈度下,层间位移角均满足我国现行抗震规范要求。该体系在高烈度区也可具有良好的抗震性能。
文摘Auxin is a key hormonal regulator,that governs plant growth and development in concert with other hormonal pathways.The unique feature of auxin is its polar,cell-to-cell transport that leads to the formation of local auxin maxima and gradients,which coordinate initiation and patterning of plant organs.The molecular machinery mediating polar auxin transport is one of the important points of interaction with other hormones.Multiple hormonal pathways converge at the regulation of auxin transport and form a regulatory network that integrates various developmental and environmental inputs to steer plant development.In this review,we discuss recent advances in understanding the mechanisms that underlie regulation of polar auxin transport by multiple hormonal pathways.Specifically,we focus on the post-translational mechanisms that contribute to fine-tuning of the abundance and polarity of auxin transporters at the plasma membrane and thereby enable rapid modification of the auxin flow to coordinate plant growth and development.
