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被子植物的胚珠微小,手工分离胚珠内的珠心比较困难(胡适宜,1994).目前,人们多是借助于纤维素酶和果胶酶等的酶解技术,完成珠心、胚囊、卵细胞和合子等微小结构的人工分离(周嫦等,1982;Huang et al,1990;Kovács et al,1994;Tian et al.,1997;杨弘远等,1998;2001;Uchiumi et al.,2006). 相似文献
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[Objective] The aim of this study was to manually isolate the microstructures such as ovule and embryo of Capsella bursa-pastoris (L.) Medic. by the non-enzymatic method. [Method] With the gum block and dissecting microscope, its floral characteristics, ovule and embryo were manually isolated and observed by the non-enzymatic method. [Result] C. bursa-pastoris had four calyces, four petals, tetradynamous stamen and silicle, while its embryogenesis contained globular embryo, heart-shaped embryo and torpedo-shaped embryo. [Conclusion] The microstructures such as ovule and embryo of plants become easier to be isolated manually with the viscosity of gum block, which has small damage on embryo or disadvantages of keeping original shapes, and also can used in multi fields studies. This test can also be accomplished in labs with poor experiment facilities. 相似文献
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桥梁橡胶支撑是公路桥梁建设中不可缺少的重要部件之一,它在桥梁建设使用中起着极其重要的作用,橡胶支座要承受桥梁自身重量及桥面的车辆负载的正向载荷,同时在冬夏季温度的变化中,温度引起的横向侧面载荷。因而,桥梁支座橡胶块应能具有的应力—应变参数对支座的安全可靠使用起到极其重要的作用。这样势必在桥梁支座的生产制造过程中,对橡胶块按照有关标准进行应力—应变参数及横向剪应力—应变参数的测定。已是控制支座生产质量不可缺少的重要检测手段。 相似文献
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充气轮胎的应用橡胶在拖拉机车轮轮缘上的应用,是从橡胶块轮缘、整条硬橡胶轮缘、零压力橡胶轮胎,逐步发展到充气橡胶轮胎阶段。橡胶块轮缘1870年,欧洲苏格兰发明家罗伯特·汤姆森在蒸汽拖拉机上采用了带橡胶轮缘的车轮。 相似文献
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