棉花分子育种研究进展

本文主要综述了我国近２０年来棉花分子育种在理论基础、技术方法、育种机理以及新品种培育等方面研究取得的成就及新进展，并讨论了棉花分子育种的发展方向     

Ye Yaxin, Jin Jin, Wang Wenjing, Xu Yu

研究Nacl浓度与小麦幼苗生长分裂的关系及对小麦幼苗的遗传损伤。实验结果表明：小麦幼苗生长在含NaCl的介质中，其幼苗生长被抑制，根尖细胞有丝分裂指数下降,幼苗的分裂指数、遗传损伤与盐浓度间有一定的线性关系。结果显示：有丝分裂指数与处理浓度间呈负相关。这表明：NaCl浓度高或作用时间延长时对小麦细胞具有遗传学毒性，小麦幼根细胞有丝分裂指数可以作为监测环境中NaCl含量的定量指标。     

Biodegradation of Linear Alkyl Benzene Sulphonate

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.     

Biocompatibility of Acellular Porcine Dermis

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.     

Experimental Study on the Deformation Characteristics of Fine-Sandstone Under the Loading and Unloading Conditions

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.     

PROBABILISTIC EVALUATION FOR STEEL FRAME COLUMNS OF TALL BUILDINGS

Based on properties of parameters and test data of dom-estic steel,this paper analyses the reliability and partial coefficient forresistance of steel frame columns of tall builings.The result may serveas a scientific basis.It is not only for domestic steel instead of importedsteel in building tall steel structures,but also for compiling concerendstandards.