The article investigated the changes of nutrients(total sugar,total nitrogen,total sugar/total N)and oxidases(IAAO,POD,PPO)of Catalpa bungei cl.’Yu-1’ in the cutting rooting process.The results showed that:C.bungei ...The article investigated the changes of nutrients(total sugar,total nitrogen,total sugar/total N)and oxidases(IAAO,POD,PPO)of Catalpa bungei cl.’Yu-1’ in the cutting rooting process.The results showed that:C.bungei cl.’Yu-1’ cutting rooting initiated from the lenticel.The soluble protein in the forced-sprouting cuttings decreased dramatically in the early stage,and then the decrease tended to slow.The total sugar content slowly increased throughout.The total nitrogen had a little change.The total sugar/total nitrogen ratio had same trend with total sugar.The IAAO,PPO activity of the forced-sprouting cuttings showed up-down-up-down pattern in the rooting process,The POD activity rose in undulation pattern.The role of three oxidases was both independent with each other,and related to one another in the process of rooting by which affected rooting in integration.展开更多
文摘The article investigated the changes of nutrients(total sugar,total nitrogen,total sugar/total N)and oxidases(IAAO,POD,PPO)of Catalpa bungei cl.’Yu-1’ in the cutting rooting process.The results showed that:C.bungei cl.’Yu-1’ cutting rooting initiated from the lenticel.The soluble protein in the forced-sprouting cuttings decreased dramatically in the early stage,and then the decrease tended to slow.The total sugar content slowly increased throughout.The total nitrogen had a little change.The total sugar/total nitrogen ratio had same trend with total sugar.The IAAO,PPO activity of the forced-sprouting cuttings showed up-down-up-down pattern in the rooting process,The POD activity rose in undulation pattern.The role of three oxidases was both independent with each other,and related to one another in the process of rooting by which affected rooting in integration.
文摘为深入揭示碳纤维增强树脂基复合材料(Carbon fiber reinforced plastic/polymer,CFRP)切削机理,针对目前宏观单相有限元方法无法直观体现纤维和基体的失效形式、切屑类型等问题,借助数值仿真方法建立了CFRP直角切削的三维多相有限元模型。测量刀具刀尖形貌,根据刀具和CFRP设计数据提取CFRP纤维、基体细观几何信息,建立直角切削细观几何模型;基于定义材料本构用户子程序(User subroutine to define material behavior,VUMAT)分别定义纤维和基体的材料本构(弹塑性、失效准则、损伤演化方式),对不同纤维方向角的三维多相CFRP直角切削模型进行仿真分析;设计直角切削试验对仿真结果进行对比验证。仿真结果直观地展示了基体和纤维的失效形式、切屑形成过程、不同情况下切削亚表面损伤深度,通过各种情况下切削力数据的分析,揭示了切削力随纤维方向角的变化规律,并通过试验验证了该有限元建模仿真方法的有效性。
