为了探讨外源亚精胺对低温条件下菜豆种子萌发与种子耐低温性的影响。本研究以菜豆品种‘热那亚’为试验材料,设置常温对照(CK)、4℃低温(LT)以及4℃低温条件下添加1 mmol/L Spd (LT+Spd) 3个处理组,对其发芽率、发芽指数、种子活力及...为了探讨外源亚精胺对低温条件下菜豆种子萌发与种子耐低温性的影响。本研究以菜豆品种‘热那亚’为试验材料,设置常温对照(CK)、4℃低温(LT)以及4℃低温条件下添加1 mmol/L Spd (LT+Spd) 3个处理组,对其发芽率、发芽指数、种子活力及生理指标进行测定。结果显示:4℃低温条件下,添加1 mmol/L的Spd后菜豆种子发芽率、发芽指数和种子活力分别提高了95.69%、136.10%和217.12%;电解质外渗率降低;抗氧化酶SOD、POD、CAT的活性升高;H2O2、O2-、MDA、脯氨酸和可溶性蛋白的含量降低。由此可见,施用外源亚精胺能够缓解低温胁迫对菜豆种子造成的伤害,提高菜豆种子的耐低温性,从而提高菜豆种子的发芽率、发芽指数和种子活力。展开更多
Surface processes of CO_(2)reduction on Pt(210),Pt(310),and Pt(510)electrodes were studied by cyclic voltammetry.Different surface structures of these platinum single crystal electrodes were obtained by various treatm...Surface processes of CO_(2)reduction on Pt(210),Pt(310),and Pt(510)electrodes were studied by cyclic voltammetry.Different surface structures of these platinum single crystal electrodes were obtained by various treatment conditions.The experimental results illustrated that the electrocatalytic activity of Pt single crystal electrodes towards CO_(2)reduction is decreased in an order of Pt(210)>Pt(310)>Pt(510),i.e.,with the decrease of(110)step density on well-defined surfaces.When the surfaces were reconstructed due to oxygen adsorption,the catalytic activity of all the three electrodes has been enhanced to a cer-tain extent.Although the activity order remains unchanged,the electrocatalytic activity has been en-hanced more significantly as the density of(110)step sites is more intensive on the Pt single crystal surface.It has revealed that the more open the surface structure is,the more active the Pt single crystal electrode will be,and the easier for the electrode to be transformed into a surface structure that exhib-its higher activity under external inductions.However,the relatively ordered surfaces of Pt single crystal electrode are comparatively stable under the same external inductions.The present study has gained knowledge on the interaction between CO_(2)and Pt single crystal electrode surfaces at a micro-scopic level,and thrown new insight into understanding the surface processes of electrocatalytic re-duction of CO_(2).展开更多
基金Supported by the National Natural Science Foundation of China(Grant Nos.20673091,20433060 and 20373059)the Special Funds for Major State Basic Research Project of China(Grant No.2002CB211804)
文摘Surface processes of CO_(2)reduction on Pt(210),Pt(310),and Pt(510)electrodes were studied by cyclic voltammetry.Different surface structures of these platinum single crystal electrodes were obtained by various treatment conditions.The experimental results illustrated that the electrocatalytic activity of Pt single crystal electrodes towards CO_(2)reduction is decreased in an order of Pt(210)>Pt(310)>Pt(510),i.e.,with the decrease of(110)step density on well-defined surfaces.When the surfaces were reconstructed due to oxygen adsorption,the catalytic activity of all the three electrodes has been enhanced to a cer-tain extent.Although the activity order remains unchanged,the electrocatalytic activity has been en-hanced more significantly as the density of(110)step sites is more intensive on the Pt single crystal surface.It has revealed that the more open the surface structure is,the more active the Pt single crystal electrode will be,and the easier for the electrode to be transformed into a surface structure that exhib-its higher activity under external inductions.However,the relatively ordered surfaces of Pt single crystal electrode are comparatively stable under the same external inductions.The present study has gained knowledge on the interaction between CO_(2)and Pt single crystal electrode surfaces at a micro-scopic level,and thrown new insight into understanding the surface processes of electrocatalytic re-duction of CO_(2).
