背景:作为骨科内植物的主要材料,钛及其合金在包括骨科在内的多个医学领域得到广泛的应用,内植物相关性感染也随之增多,采取不同的制备方法将优异且机制清楚的抗菌金属铜加入其中,在不影响生物力学性能的同时可使其具备一定的抗菌能力...背景:作为骨科内植物的主要材料,钛及其合金在包括骨科在内的多个医学领域得到广泛的应用,内植物相关性感染也随之增多,采取不同的制备方法将优异且机制清楚的抗菌金属铜加入其中,在不影响生物力学性能的同时可使其具备一定的抗菌能力。目的:综述医用含铜钛合金的抗菌性能研究进展及发展趋势。方法:应用计算机检索PubMed、Web of Science数据库中2003年1月至2022年3月的相关文献,检索词为“Titanium alloy,Copper,Antibacterial,Surface modification,Coating”,根据纳入排除标准对选定的76篇文献进行分析讨论。结果与结论:①加入铜的钛合金在体内外抗菌实验中均显示出良好的抗菌性能,并随着铜含量的提升其抗菌性能更加明显。②但目前仍存在较多问题有待解决:探索、优化加入铜的含量、方式及采取合适的制备工艺使合金的抗菌性能、生物相容性、机械性能达到平衡需要进一步的实验;表面改性对合金表面的微损伤是否会对合金造成不利影响;铜离子释放速率的控制以及如何避免早期突然大量释放铜离子的“突释现象”。展开更多
The thermal elasto-hydrodynamic lubrication characteristics of the internal meshing gears in a planetary gear train under vibrations were examined considering the influence of the modification coefficient and time-var...The thermal elasto-hydrodynamic lubrication characteristics of the internal meshing gears in a planetary gear train under vibrations were examined considering the influence of the modification coefficient and time-varying meshing stiffness.Based on dynamic theory of the gear system,a dynamic model of the planetary gear train was established.The lubrication performances of modified gear systems under vibrations and static loads were analyzed.Compared with other transmission types,the best lubrication effect could be produced by the positive transmission.A thicker lubricating oil film could be formed,and the friction coefficient and oil film flash temperature are the smallest.Increasing modification coefficient improves the lubrication performance continuously but intensifies the engage-in and tooth-change impact.For the planetary and inner gears,the increase in the modification coefficient also leads a decrease in the oil film stiffness.展开更多
文摘背景:作为骨科内植物的主要材料,钛及其合金在包括骨科在内的多个医学领域得到广泛的应用,内植物相关性感染也随之增多,采取不同的制备方法将优异且机制清楚的抗菌金属铜加入其中,在不影响生物力学性能的同时可使其具备一定的抗菌能力。目的:综述医用含铜钛合金的抗菌性能研究进展及发展趋势。方法:应用计算机检索PubMed、Web of Science数据库中2003年1月至2022年3月的相关文献,检索词为“Titanium alloy,Copper,Antibacterial,Surface modification,Coating”,根据纳入排除标准对选定的76篇文献进行分析讨论。结果与结论:①加入铜的钛合金在体内外抗菌实验中均显示出良好的抗菌性能,并随着铜含量的提升其抗菌性能更加明显。②但目前仍存在较多问题有待解决:探索、优化加入铜的含量、方式及采取合适的制备工艺使合金的抗菌性能、生物相容性、机械性能达到平衡需要进一步的实验;表面改性对合金表面的微损伤是否会对合金造成不利影响;铜离子释放速率的控制以及如何避免早期突然大量释放铜离子的“突释现象”。
基金Projects(51575289,51705270)supported by the National Natural Science Foundation of China。
文摘The thermal elasto-hydrodynamic lubrication characteristics of the internal meshing gears in a planetary gear train under vibrations were examined considering the influence of the modification coefficient and time-varying meshing stiffness.Based on dynamic theory of the gear system,a dynamic model of the planetary gear train was established.The lubrication performances of modified gear systems under vibrations and static loads were analyzed.Compared with other transmission types,the best lubrication effect could be produced by the positive transmission.A thicker lubricating oil film could be formed,and the friction coefficient and oil film flash temperature are the smallest.Increasing modification coefficient improves the lubrication performance continuously but intensifies the engage-in and tooth-change impact.For the planetary and inner gears,the increase in the modification coefficient also leads a decrease in the oil film stiffness.
