三种连接方式结构保温板(SIPs)传热性能研究

SIPs (Structural Insulated Panels)在实际工程中常用的连接方式有三种,连接部位是墙体的热桥部位,影响墙体的整体传热性能。笔者采用一维稳态热箱法对三种连接方式进行测试,分别对比覆面板为杉木指接材SIP墙体三种不同连接方式的热流密度、传热均匀性、温差分布等热工性能,结果显示使用小尺寸SIP作为墙体间连接具有较低的传热系数和较稳定的传热性能,综合传热性能较好。     

GFRP筋增强胶合木梁抗弯性能研究北大核心

为研究内嵌GFRP筋增强胶合木梁的抗弯性能,制作了11根铁杉胶合木梁,依据欧洲BS EN 408标准,对其进行四点弯曲加载试验。试验参数包括:开槽位置、槽口数量及槽口形状。试验结果表明:对胶合木梁开槽会使胶合木梁的抗弯性能显著下降,而圆形槽口对于木材的破坏程度小于方槽;同时在受拉区和受压区对胶合木梁增强,其效果比单独在受拉区增强的效果更好,极限荷载和延性系数分别提高了5.88%、16.85%;仅在木梁受拉区增强时,增加GFRP筋的数量,除了延性得到改善外,刚度和极限承载能力均降低;采用圆形槽口增强时,其增强效果优于用方槽对胶合木梁的增强。     

Effect of Phytohormones on Adventitious Bud Differentiation from Bulb Scales of Oriental Lily Test-tube Plantlets

[Objective] The purpose of this study is to investigate the effects of differ- ent phytohormones on the adventitious bud differentiation of oriental lily. [Method] The bulb scales of the test-tube plantlets of Tiber, Rodina and Constanta were cul- tured in media supplemented with different cytokinin and auxin at different concen- tration, and then the adventitious buds in each treatment were calculated. [Result] Cytokinins had different influence on the adventitious bud differentiation of the three oriental lily cultivars. Among them, 6-BA had the best effect to induce the adventi- tious bud differentiation from bulb scales of Tiber and Rodina, but there was some difference in the optimal concentration. KT had the best effect to induce the adven- titious bud differentiation of Constanta. The auxins had little influence on the quality of the adventitious bud of the three oriental lily cultivars, but caused some difference in differentiation coefficients. [Conclusion] The most suitable media for the adventi- tious bud differentiation from bulb scales in vitro of Tiber, Rodina and Constanta were MS＋0.2 mg/L 6-BA＋0.2 mg/L 2,4-D, MS＋I.0 mg/L 6-BA＋0.2 mg/L IAA, MS＋ 1.0 mg/L KT＋0.5 mg/L 2,4-D, respectively.     

植物激素对东方百合试管苗鳞片分化不定芽的影响

以Tiber、Rodina、Constanta试管苗鳞片为材料,研究不同激素种类及浓度对试管苗鳞片分化不定芽的影响.结果表明,细胞分裂素对东方百合鳞片分化能力的影响在品种间存在差异,其中6-BA对Tiber和Rodina鳞片分化不定芽的作用效果最好,只是在适宜的浓度水平上因品种不同有所差异.KT对Constanta鳞片分化不定芽的作用效果最好.生长素对3种东方百合试管苗鳞片分化不定芽质量影响差异不明显,只是在分化系数上有所差异.适合3种东方百合试管苗鳞片分化不定芽的培养基分别为MS+0.2 mg/L 6-BA +0.2 mg/L2,4-D (Tiber)、MS+ 1.0 mg/L6-BA+ 0.2 mg/L IAA(Rodina)、MS+ 1.0 mg/L KT+ 0.5 mg/L2,4-D(Constanta).     

蜡梅切花观赏特性的综合评价

依据实地调查记录与蜡梅品种分类相关资料，采用层次分析法，对30个观赏性状较好的蜡梅品种进行综合评价，选择出十多种适合切花应用的品种。