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钢管桩作为钢栈桥的重要组成构件，在海洋环境下会受到严重的腐蚀威胁。研究了东海某钢栈桥经历5年海洋自然腐蚀后钢管桩的材料性能。从钢管桩的浪溅区、潮差区和全浸区共加工16个拉伸试件，分析各区域的退化力学性能，根据试验数据建立弹性模量、屈服强度、应变硬化指数和强度系数等参数与平均厚度剩余率相关的回归方程，依据三线型本构模型建立3个区域真实应力-应变曲线的拟合公式。结果表明：浪溅区受腐蚀影响最严重，各区域钢材力学性能均存在一定损失；回归方程可以较好地预测3个区域的屈服强度；通过比较各区域的平均厚度剩余率适用范围，可知三线型本构拟合公式适用于腐蚀较为严重的钢管桩。

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the transfection effect of gene vector based on low molecular weight polyethylenimine ( PEI), Michael addition reaction was used to graft PEI 600 Da onto biodegradable polyesters containing hydrophobic chains to form a series of comblike polymers, and then they were applied to the gene vector. The chemical structure and molecular weight of the polymers were determined by utilizing 1 HNMR and gel permeation chromatography respectively. Additionally, the binding ability of the polymers and DNA, the transfection performance of their complexes were also studied by use of gel electrophoresis and green fluorescent protein assay. The results show that a series of oligomers are successfully synthesized, by which DNA can be packaged well. The transfection effect of oleic acid-modified oligomer / DNA complex is similar to that of PEI 25 kDa at mass ratio 6. 4. It is concluded that oleic acid-modified liposome oligomer has the potential to be used as non-viral gene vector. [ABSTRACT FROM AUTHOR]

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)