目的研究何首乌Polygonum multiflorum的化学成分。方法采用大孔吸附树脂(DM-8型)、Sephadex LH-20、反相硅胶柱色谱和液相制备等多种色谱技术进行分离纯化,采用核磁共振等波谱技术进行结构鉴定。结果从何首乌提取物55%乙醇洗脱部位中分离得到10个化合物,分别鉴定为thunberginol c 6-O-β-D-glucopyranoside(1)、对羟基苯甲醛(2)、反式-N-咖啡酰酪胺(3)、(Z)-2,3,5,4′-四羟基二苯乙烯-2-O-β-D-葡萄糖苷(4)、(E)-2,3,5,4′-四羟基二苯乙烯-2-O-β-D-葡萄糖苷(5)、白藜芦醇-3-O-β-D-(2″-O-没食子酰)-葡萄糖苷(6)、(E)-2,3,5,4′-四羟基二苯乙烯-2-O-β-D-(3″-没食子酰)-葡萄糖苷(7)、苜蓿素-7-O-β-D-葡萄糖苷(8)、torachrysone-8-O-β-D-glucoside(9)、大黄素-8-O-β-D-葡萄糖苷(10)。结论化合物1为新化合物,命名为何首乌丁素。化合物3和8为首次从何首乌中分离得到。
c 8368是赤峰市农牧科学研究院以自育的胞质雄性不育系052 A为母本,胞质雄性不育恢复系089 R为父本配制的食用向日葵杂交种。通过2009年品比试验,2010年内蒙古自治区预备试验,2011年内蒙古自治区区域试验,2012年内蒙古自治区生产试验,...
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c 8368是赤峰市农牧科学研究院以自育的胞质雄性不育系052 A为母本,胞质雄性不育恢复系089 R为父本配制的食用向日葵杂交种。通过2009年品比试验,2010年内蒙古自治区预备试验,2011年内蒙古自治区区域试验,2012年内蒙古自治区生产试验,该品种表现产量高、抗病性强、商品性好、适应性广等特点。2013年通过内蒙古自治区农作物品种审定。
The ferritic P22 and bainitic-martenstic P91 steel welded joints operating at elevated temperatures are highly vulnerable to premature failure, because microstructure gradients can lead to cracking in the heat-affecte...
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The ferritic P22 and bainitic-martenstic P91 steel welded joints operating at elevated temperatures are highly vulnerable to premature failure, because microstructure gradients can lead to cracking in the heat-affected zone, commonly referred to as type IV cracking. creep crack growth tests have been performed using compact tension specimens made of P91 and P22 weld joints at temperatures of 600 and 550 degrees c, respectively. The creep crack growth characterization through empirical equation of c* was the main fracture parameter for relating behaviour of component's regions. Results have shown that, for a specific value of c* parameter, the weld metal and heat-affected zone had similar crack growth rates, which were about two times faster than base metal rates, because of lower creep strength that leads to a conclusion that the creep cracks will most likely initiate in the heat-affected zone region.
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