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排序方式: 共有7490条查询结果,搜索用时 15 毫秒
81.
水稻闭颖授粉特性的遗传及其生物学意义 总被引:5,自引:0,他引:5
在正常条件下,水稻闭颖授粉特性是一种罕见的性状。已知具有这种特性的水稻品种有兴除1号和小麦稻。遗传分析表明,闭颖授粉受一对隐性核基因控制。试验结果表明,开花期遇到低温或连续降雨时,这种特性有利于水稻受精结实。此外还可看到,闭颖授粉特性能防止异花授粉,对保持种性有重要的生物学意义。 相似文献
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XIANG Li-jun WANG Bo-chu DUAN Chuan-ren LIU Liu WANG Qing-hongnistry of Education College of Bioengineering Chongqing University Chongqing Chin 《保鲜与加工》2004,(10):71-74
The paper researches on the degradation of LAS (Linear Alkyl benzene Sulphonate) by combining AS1.860 immobilized with low intensity ultrasonic irradiation. The paper also discusses the influence of pH, rotary velocity, LAS concentration and the condition of low intensity ultrasonic irradiation on the degradation of LAS, the degradation rate of LAS is the main index of our experiment, the results of orthogonal test shows that low ultrasonic irradiation can increase the metabolizing of microorganism cells and facilitate the biodegradation of immobilized cells to LAS, here we research the degradation condition of 50mg/L LAS simulation wastewater with low ultrasonic irradiation, and the results show that the influence is obvious, the optimization degradation rate is about 83%, nine point five percent higher than that of the immobilized cells without ultrasonic irradiation. 相似文献
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SU Ai-hu WANG Yuan-liang TANG Li-ling PAN Jun LUO Yan-fengstry of Education College of Bioengineering Chongqing University Chongqing Chin 《保鲜与加工》2004,(2):99-101
In vitro cultured vascular endothelial cells (VEC) and mouse 3T3 fibroblasts (3T3) on the acellular dermal matrix , which were made of porcine skins. We made the cell proliferation test with MTT assay and the histological observation after cells were seeded on the acelluar dermis for 1 week with histological section. The cell growth curves showed VEC and 3T3 grew much rapidly on the acelluar dermis.The histological observation revealed VEC had formed a monolayer, some places even had formed 2 to 3 layer. The results suggest that the acelluar porcine dermal matrix have good biocompatibility , it will be widely applied. 相似文献
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XU Jiang WANG Wei-zhong YANG Xiu-gui WANG Hongl Disaster Control Engineering Under the State Ministry of Education Chongqing University Chongqing Chin 《保鲜与加工》2004,(12):60-62
The deformation characteristics of the fine-sandstone is studied under the loading and unloading conditions at the three different deformation-rates and the two different stress-levels. The experimental results show that there is really the plastic-loop in the deformation curve for the loading deformation curve is different from the unloading deformation curve. But the plastic-loop is nearly unchangeable since the second circulate loading. The residual-deformation is be almost zero since the second circulate loading, and that the slope of the deformation curve increases as the deformation-rate increases, and that the residual-deformation increases as the stress-levels increases. 相似文献
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